A smaller, kinder, gentler regexp implementation.

3 files changed, 5726 insertions, 7274 deletions

diff --git a/libc/misc/regex/Makefile b/libc/misc/regex/Makefile
index c4c13f6cf..38b7e98bf 100644
--- a/libc/misc/regex/Makefile
+++ b/libc/misc/regex/Makefile
@@ -24,7 +24,7 @@ TOPDIR=../../
 include $(TOPDIR)Rules.mak
 LIBC=$(TOPDIR)libc.a
 
-CSRC=rx.c
+CSRC=regex.c
 COBJS=$(patsubst %.c,%.o, $(CSRC))
 OBJS=$(COBJS)
 
diff --git a/libc/misc/regex/regex.c b/libc/misc/regex/regex.c
new file mode 100644
index 000000000..64e754ee0
--- /dev/null
+++ b/libc/misc/regex/regex.c
@@ -0,0 +1,5725 @@
+/* Extended regular expression matching and search library,
+   version 0.12.
+   (Implements POSIX draft P1003.2/D11.2, except for some of the
+   internationalization features.)
+   Copyright (C) 1993-1999, 2000 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* AIX requires this to be the first thing in the file. */
+#if defined _AIX && !defined REGEX_MALLOC
+#pragma alloca
+#endif
+
+#undef	_GNU_SOURCE
+#define _GNU_SOURCE
+#define STDC_HEADERS
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#ifndef PARAMS
+# if defined __GNUC__ || (defined __STDC__ && __STDC__)
+#  define PARAMS(args) args
+# else
+#  define PARAMS(args) ()
+# endif							/* GCC.  */
+#endif							/* Not PARAMS.  */
+
+#if defined STDC_HEADERS && !defined emacs
+# include <stddef.h>
+#else
+/* We need this for `regex.h', and perhaps for the Emacs include files.  */
+# include <sys/types.h>
+#endif
+
+#define WIDE_CHAR_SUPPORT (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC)
+
+/* For platform which support the ISO C amendement 1 functionality we
+   support user defined character classes.  */
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+/* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>.  */
+# include <wchar.h>
+# include <wctype.h>
+#endif
+
+#ifdef _LIBC
+/* We have to keep the namespace clean.  */
+# define regfree(preg) __regfree (preg)
+# define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
+# define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
+# define regerror(errcode, preg, errbuf, errbuf_size) \
+	__regerror(errcode, preg, errbuf, errbuf_size)
+# define re_set_registers(bu, re, nu, st, en) \
+	__re_set_registers (bu, re, nu, st, en)
+# define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
+	__re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
+# define re_match(bufp, string, size, pos, regs) \
+	__re_match (bufp, string, size, pos, regs)
+# define re_search(bufp, string, size, startpos, range, regs) \
+	__re_search (bufp, string, size, startpos, range, regs)
+# define re_compile_pattern(pattern, length, bufp) \
+	__re_compile_pattern (pattern, length, bufp)
+# define re_set_syntax(syntax) __re_set_syntax (syntax)
+# define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
+	__re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
+# define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
+
+#define btowc __btowc
+#endif
+
+/* This is for other GNU distributions with internationalized messages.  */
+#if HAVE_LIBINTL_H || defined _LIBC
+# include <libintl.h>
+#else
+# define gettext(msgid) (msgid)
+#endif
+
+#ifndef gettext_noop
+/* This define is so xgettext can find the internationalizable
+   strings.  */
+# define gettext_noop(String) String
+#endif
+
+/* The `emacs' switch turns on certain matching commands
+   that make sense only in Emacs. */
+#ifdef emacs
+
+# include "lisp.h"
+# include "buffer.h"
+# include "syntax.h"
+
+#else							/* not emacs */
+
+/* If we are not linking with Emacs proper,
+   we can't use the relocating allocator
+   even if config.h says that we can.  */
+# undef REL_ALLOC
+
+# if defined STDC_HEADERS || defined _LIBC
+#  include <stdlib.h>
+# else
+char *malloc();
+char *realloc();
+# endif
+
+/* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
+   If nothing else has been done, use the method below.  */
+# ifdef INHIBIT_STRING_HEADER
+#  if !(defined HAVE_BZERO && defined HAVE_BCOPY)
+#   if !defined bzero && !defined bcopy
+#    undef INHIBIT_STRING_HEADER
+#   endif
+#  endif
+# endif
+
+/* This is the normal way of making sure we have a bcopy and a bzero.
+   This is used in most programs--a few other programs avoid this
+   by defining INHIBIT_STRING_HEADER.  */
+# ifndef INHIBIT_STRING_HEADER
+#  if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
+#   include <string.h>
+#   ifndef bzero
+#    ifndef _LIBC
+#     define bzero(s, n)	(memset (s, '\0', n), (s))
+#    else
+#     define bzero(s, n)	__bzero (s, n)
+#    endif
+#   endif
+#  else
+#   include <strings.h>
+#   ifndef memcmp
+#    define memcmp(s1, s2, n)	bcmp (s1, s2, n)
+#   endif
+#   ifndef memcpy
+#    define memcpy(d, s, n)	(bcopy (s, d, n), (d))
+#   endif
+#  endif
+# endif
+
+/* Define the syntax stuff for \<, \>, etc.  */
+
+/* This must be nonzero for the wordchar and notwordchar pattern
+   commands in re_match_2.  */
+# ifndef Sword
+#  define Sword 1
+# endif
+
+# ifdef SWITCH_ENUM_BUG
+#  define SWITCH_ENUM_CAST(x) ((int)(x))
+# else
+#  define SWITCH_ENUM_CAST(x) (x)
+# endif
+
+#endif							/* not emacs */
+
+/* Get the interface, including the syntax bits.  */
+#include <regex.h>
+
+/* isalpha etc. are used for the character classes.  */
+#include <ctype.h>
+
+/* Jim Meyering writes:
+
+   "... Some ctype macros are valid only for character codes that
+   isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
+   using /bin/cc or gcc but without giving an ansi option).  So, all
+   ctype uses should be through macros like ISPRINT...  If
+   STDC_HEADERS is defined, then autoconf has verified that the ctype
+   macros don't need to be guarded with references to isascii. ...
+   Defining isascii to 1 should let any compiler worth its salt
+   eliminate the && through constant folding."
+   Solaris defines some of these symbols so we must undefine them first.  */
+
+#undef ISASCII
+#if defined STDC_HEADERS || (!defined isascii && !defined HAVE_ISASCII)
+# define ISASCII(c) 1
+#else
+# define ISASCII(c) isascii(c)
+#endif
+
+#ifdef isblank
+# define ISBLANK(c) (ISASCII (c) && isblank (c))
+#else
+# define ISBLANK(c) ((c) == ' ' || (c) == '\t')
+#endif
+#ifdef isgraph
+# define ISGRAPH(c) (ISASCII (c) && isgraph (c))
+#else
+# define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
+#endif
+
+#undef ISPRINT
+#define ISPRINT(c) (ISASCII (c) && isprint (c))
+#define ISDIGIT(c) (ISASCII (c) && isdigit (c))
+#define ISALNUM(c) (ISASCII (c) && isalnum (c))
+#define ISALPHA(c) (ISASCII (c) && isalpha (c))
+#define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
+#define ISLOWER(c) (ISASCII (c) && islower (c))
+#define ISPUNCT(c) (ISASCII (c) && ispunct (c))
+#define ISSPACE(c) (ISASCII (c) && isspace (c))
+#define ISUPPER(c) (ISASCII (c) && isupper (c))
+#define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
+
+#ifdef _tolower
+# define TOLOWER(c) _tolower(c)
+#else
+# define TOLOWER(c) tolower(c)
+#endif
+
+#ifndef NULL
+# define NULL (void *)0
+#endif
+
+/* We remove any previous definition of `SIGN_EXTEND_CHAR',
+   since ours (we hope) works properly with all combinations of
+   machines, compilers, `char' and `unsigned char' argument types.
+   (Per Bothner suggested the basic approach.)  */
+#undef SIGN_EXTEND_CHAR
+#if __STDC__
+# define SIGN_EXTEND_CHAR(c) ((signed char) (c))
+#else							/* not __STDC__ */
+/* As in Harbison and Steele.  */
+# define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
+#endif
+
+#ifndef emacs
+/* How many characters in the character set.  */
+# define CHAR_SET_SIZE 256
+
+# ifdef SYNTAX_TABLE
+
+extern char *re_syntax_table;
+
+# else							/* not SYNTAX_TABLE */
+
+static char re_syntax_table[CHAR_SET_SIZE];
+
+static void init_syntax_once()
+{
+	register int c;
+	static int done = 0;
+
+	if (done)
+		return;
+	bzero(re_syntax_table, sizeof re_syntax_table);
+
+	for (c = 0; c < CHAR_SET_SIZE; ++c)
+		if (ISALNUM(c))
+			re_syntax_table[c] = Sword;
+
+	re_syntax_table['_'] = Sword;
+
+	done = 1;
+}
+
+# endif							/* not SYNTAX_TABLE */
+
+# define SYNTAX(c) re_syntax_table[((c) & 0xFF)]
+
+#endif							/* emacs */
+
+/* Should we use malloc or alloca?  If REGEX_MALLOC is not defined, we
+   use `alloca' instead of `malloc'.  This is because using malloc in
+   re_search* or re_match* could cause memory leaks when C-g is used in
+   Emacs; also, malloc is slower and causes storage fragmentation.  On
+   the other hand, malloc is more portable, and easier to debug.
+
+   Because we sometimes use alloca, some routines have to be macros,
+   not functions -- `alloca'-allocated space disappears at the end of the
+   function it is called in.  */
+
+#ifdef REGEX_MALLOC
+
+# define REGEX_ALLOCATE malloc
+# define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
+# define REGEX_FREE free
+
+#else							/* not REGEX_MALLOC  */
+
+/* Emacs already defines alloca, sometimes.  */
+# ifndef alloca
+
+/* Make alloca work the best possible way.  */
+#  ifdef __GNUC__
+#   define alloca __builtin_alloca
+#  else							/* not __GNUC__ */
+#   if HAVE_ALLOCA_H
+#    include <alloca.h>
+#   endif						/* HAVE_ALLOCA_H */
+#  endif						/* not __GNUC__ */
+
+# endif							/* not alloca */
+
+# define REGEX_ALLOCATE alloca
+
+/* Assumes a `char *destination' variable.  */
+# define REGEX_REALLOCATE(source, osize, nsize)				\
+  (destination = (char *) alloca (nsize),				\
+   memcpy (destination, source, osize))
+
+/* No need to do anything to free, after alloca.  */
+# define REGEX_FREE(arg) ((void)0)	/* Do nothing!  But inhibit gcc warning.  */
+
+#endif							/* not REGEX_MALLOC */
+
+/* Define how to allocate the failure stack.  */
+
+#if defined REL_ALLOC && defined REGEX_MALLOC
+
+# define REGEX_ALLOCATE_STACK(size)				\
+  r_alloc (&failure_stack_ptr, (size))
+# define REGEX_REALLOCATE_STACK(source, osize, nsize)		\
+  r_re_alloc (&failure_stack_ptr, (nsize))
+# define REGEX_FREE_STACK(ptr)					\
+  r_alloc_free (&failure_stack_ptr)
+
+#else							/* not using relocating allocator */
+
+# ifdef REGEX_MALLOC
+
+#  define REGEX_ALLOCATE_STACK malloc
+#  define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
+#  define REGEX_FREE_STACK free
+
+# else							/* not REGEX_MALLOC */
+
+#  define REGEX_ALLOCATE_STACK alloca
+
+#  define REGEX_REALLOCATE_STACK(source, osize, nsize)			\
+   REGEX_REALLOCATE (source, osize, nsize)
+/* No need to explicitly free anything.  */
+#  define REGEX_FREE_STACK(arg)
+
+# endif							/* not REGEX_MALLOC */
+#endif							/* not using relocating allocator */
+
+
+/* True if `size1' is non-NULL and PTR is pointing anywhere inside
+   `string1' or just past its end.  This works if PTR is NULL, which is
+   a good thing.  */
+#define FIRST_STRING_P(ptr) 					\
+  (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
+
+/* (Re)Allocate N items of type T using malloc, or fail.  */
+#define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
+#define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
+#define RETALLOC_IF(addr, n, t) \
+  if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
+#define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
+
+#define BYTEWIDTH 8				/* In bits.  */
+
+#define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
+
+#undef MAX
+#undef MIN
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+
+typedef char boolean;
+
+#define false 0
+#define true 1
+
+static int re_match_2_internal PARAMS((struct re_pattern_buffer * bufp,
+									   const char *string1, int size1,
+									   const char *string2, int size2,
+									   int pos,
+									   struct re_registers * regs,
+
+									   int stop));
+
+/* These are the command codes that appear in compiled regular
+   expressions.  Some opcodes are followed by argument bytes.  A
+   command code can specify any interpretation whatsoever for its
+   arguments.  Zero bytes may appear in the compiled regular expression.  */
+
+typedef enum {
+	no_op = 0,
+
+	/* Succeed right away--no more backtracking.  */
+	succeed,
+
+	/* Followed by one byte giving n, then by n literal bytes.  */
+	exactn,
+
+	/* Matches any (more or less) character.  */
+	anychar,
+
+	/* Matches any one char belonging to specified set.  First
+	   following byte is number of bitmap bytes.  Then come bytes
+	   for a bitmap saying which chars are in.  Bits in each byte
+	   are ordered low-bit-first.  A character is in the set if its
+	   bit is 1.  A character too large to have a bit in the map is
+	   automatically not in the set.  */
+	charset,
+
+	/* Same parameters as charset, but match any character that is
+	   not one of those specified.  */
+	charset_not,
+
+	/* Start remembering the text that is matched, for storing in a
+	   register.  Followed by one byte with the register number, in
+	   the range 0 to one less than the pattern buffer's re_nsub
+	   field.  Then followed by one byte with the number of groups
+	   inner to this one.  (This last has to be part of the
+	   start_memory only because we need it in the on_failure_jump
+	   of re_match_2.)  */
+	start_memory,
+
+	/* Stop remembering the text that is matched and store it in a
+	   memory register.  Followed by one byte with the register
+	   number, in the range 0 to one less than `re_nsub' in the
+	   pattern buffer, and one byte with the number of inner groups,
+	   just like `start_memory'.  (We need the number of inner
+	   groups here because we don't have any easy way of finding the
+	   corresponding start_memory when we're at a stop_memory.)  */
+	stop_memory,
+
+	/* Match a duplicate of something remembered. Followed by one
+	   byte containing the register number.  */
+	duplicate,
+
+	/* Fail unless at beginning of line.  */
+	begline,
+
+	/* Fail unless at end of line.  */
+	endline,
+
+	/* Succeeds if at beginning of buffer (if emacs) or at beginning
+	   of string to be matched (if not).  */
+	begbuf,
+
+	/* Analogously, for end of buffer/string.  */
+	endbuf,
+
+	/* Followed by two byte relative address to which to jump.  */
+	jump,
+
+	/* Same as jump, but marks the end of an alternative.  */
+	jump_past_alt,
+
+	/* Followed by two-byte relative address of place to resume at
+	   in case of failure.  */
+	on_failure_jump,
+
+	/* Like on_failure_jump, but pushes a placeholder instead of the
+	   current string position when executed.  */
+	on_failure_keep_string_jump,
+
+	/* Throw away latest failure point and then jump to following
+	   two-byte relative address.  */
+	pop_failure_jump,
+
+	/* Change to pop_failure_jump if know won't have to backtrack to
+	   match; otherwise change to jump.  This is used to jump
+	   back to the beginning of a repeat.  If what follows this jump
+	   clearly won't match what the repeat does, such that we can be
+	   sure that there is no use backtracking out of repetitions
+	   already matched, then we change it to a pop_failure_jump.
+	   Followed by two-byte address.  */
+	maybe_pop_jump,
+
+	/* Jump to following two-byte address, and push a dummy failure
+	   point. This failure point will be thrown away if an attempt
+	   is made to use it for a failure.  A `+' construct makes this
+	   before the first repeat.  Also used as an intermediary kind
+	   of jump when compiling an alternative.  */
+	dummy_failure_jump,
+
+	/* Push a dummy failure point and continue.  Used at the end of
+	   alternatives.  */
+	push_dummy_failure,
+
+	/* Followed by two-byte relative address and two-byte number n.
+	   After matching N times, jump to the address upon failure.  */
+	succeed_n,
+
+	/* Followed by two-byte relative address, and two-byte number n.
+	   Jump to the address N times, then fail.  */
+	jump_n,
+
+	/* Set the following two-byte relative address to the
+	   subsequent two-byte number.  The address *includes* the two
+	   bytes of number.  */
+	set_number_at,
+
+	wordchar,					/* Matches any word-constituent character.  */
+	notwordchar,				/* Matches any char that is not a word-constituent.  */
+
+	wordbeg,					/* Succeeds if at word beginning.  */
+	wordend,					/* Succeeds if at word end.  */
+
+	wordbound,					/* Succeeds if at a word boundary.  */
+	notwordbound				/* Succeeds if not at a word boundary.  */
+#ifdef emacs
+		, before_dot,			/* Succeeds if before point.  */
+	at_dot,						/* Succeeds if at point.  */
+	after_dot,					/* Succeeds if after point.  */
+
+	/* Matches any character whose syntax is specified.  Followed by
+	   a byte which contains a syntax code, e.g., Sword.  */
+	syntaxspec,
+
+	/* Matches any character whose syntax is not that specified.  */
+	notsyntaxspec
+#endif							/* emacs */
+} re_opcode_t;
+
+/* Common operations on the compiled pattern.  */
+
+/* Store NUMBER in two contiguous bytes starting at DESTINATION.  */
+
+#define STORE_NUMBER(destination, number)				\
+  do {									\
+    (destination)[0] = (number) & 0377;					\
+    (destination)[1] = (number) >> 8;					\
+  } while (0)
+
+/* Same as STORE_NUMBER, except increment DESTINATION to
+   the byte after where the number is stored.  Therefore, DESTINATION
+   must be an lvalue.  */
+
+#define STORE_NUMBER_AND_INCR(destination, number)			\
+  do {									\
+    STORE_NUMBER (destination, number);					\
+    (destination) += 2;							\
+  } while (0)
+
+/* Put into DESTINATION a number stored in two contiguous bytes starting
+   at SOURCE.  */
+
+#define EXTRACT_NUMBER(destination, source)				\
+  do {									\
+    (destination) = *(source) & 0377;					\
+    (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8;		\
+  } while (0)
+
+#ifdef DEBUG
+static void extract_number _RE_ARGS((int *dest, unsigned char *source));
+static void extract_number(dest, source)
+int *dest;
+unsigned char *source;
+{
+	int temp = SIGN_EXTEND_CHAR(*(source + 1));
+
+	*dest = *source & 0377;
+	*dest += temp << 8;
+}
+
+# ifndef EXTRACT_MACROS			/* To debug the macros.  */
+#  undef EXTRACT_NUMBER
+#  define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
+# endif							/* not EXTRACT_MACROS */
+
+#endif							/* DEBUG */
+
+/* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
+   SOURCE must be an lvalue.  */
+
+#define EXTRACT_NUMBER_AND_INCR(destination, source)			\
+  do {									\
+    EXTRACT_NUMBER (destination, source);				\
+    (source) += 2; 							\
+  } while (0)
+
+#ifdef DEBUG
+static void extract_number_and_incr _RE_ARGS((int *destination,
+											  unsigned char **source));
+static void extract_number_and_incr(destination, source)
+int *destination;
+unsigned char **source;
+{
+	extract_number(destination, *source);
+	*source += 2;
+}
+
+# ifndef EXTRACT_MACROS
+#  undef EXTRACT_NUMBER_AND_INCR
+#  define EXTRACT_NUMBER_AND_INCR(dest, src) \
+  extract_number_and_incr (&dest, &src)
+# endif							/* not EXTRACT_MACROS */
+
+#endif							/* DEBUG */
+
+/* If DEBUG is defined, Regex prints many voluminous messages about what
+   it is doing (if the variable `debug' is nonzero).  If linked with the
+   main program in `iregex.c', you can enter patterns and strings
+   interactively.  And if linked with the main program in `main.c' and
+   the other test files, you can run the already-written tests.  */
+
+#ifdef DEBUG
+
+/* We use standard I/O for debugging.  */
+# include <stdio.h>
+
+/* It is useful to test things that ``must'' be true when debugging.  */
+# include <assert.h>
+
+static int debug;
+
+# define DEBUG_STATEMENT(e) e
+# define DEBUG_PRINT1(x) if (debug) printf (x)
+# define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
+# define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
+# define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
+# define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) 				\
+  if (debug) print_partial_compiled_pattern (s, e)
+# define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)			\
+  if (debug) print_double_string (w, s1, sz1, s2, sz2)
+
+
+/* Print the fastmap in human-readable form.  */
+
+void print_fastmap(fastmap)
+char *fastmap;
+{
+	unsigned was_a_range = 0;
+	unsigned i = 0;
+
+	while (i < (1 << BYTEWIDTH)) {
+		if (fastmap[i++]) {
+			was_a_range = 0;
+			putchar(i - 1);
+			while (i < (1 << BYTEWIDTH) && fastmap[i]) {
+				was_a_range = 1;
+				i++;
+			}
+			if (was_a_range) {
+				printf("-");
+				putchar(i - 1);
+			}
+		}
+	}
+	putchar('\n');
+}
+
+
+/* Print a compiled pattern string in human-readable form, starting at
+   the START pointer into it and ending just before the pointer END.  */
+
+void print_partial_compiled_pattern(start, end)
+unsigned char *start;
+unsigned char *end;
+{
+	int mcnt, mcnt2;
+	unsigned char *p1;
+	unsigned char *p = start;
+	unsigned char *pend = end;
+
+	if (start == NULL) {
+		printf("(null)\n");
+		return;
+	}
+
+	/* Loop over pattern commands.  */
+	while (p < pend) {
+		printf("%d:\t", p - start);
+
+		switch ((re_opcode_t) * p++) {
+		case no_op:
+			printf("/no_op");
+			break;
+
+		case exactn:
+			mcnt = *p++;
+			printf("/exactn/%d", mcnt);
+			do {
+				putchar('/');
+				putchar(*p++);
+			}
+			while (--mcnt);
+			break;
+
+		case start_memory:
+			mcnt = *p++;
+			printf("/start_memory/%d/%d", mcnt, *p++);
+			break;
+
+		case stop_memory:
+			mcnt = *p++;
+			printf("/stop_memory/%d/%d", mcnt, *p++);
+			break;
+
+		case duplicate:
+			printf("/duplicate/%d", *p++);
+			break;
+
+		case anychar:
+			printf("/anychar");
+			break;
+
+		case charset:
+		case charset_not:
+		{
+			register int c, last = -100;
+			register int in_range = 0;
+
+			printf("/charset [%s",
+				   (re_opcode_t) * (p - 1) == charset_not ? "^" : "");
+
+			assert(p + *p < pend);
+
+			for (c = 0; c < 256; c++)
+				if (c / 8 < *p && (p[1 + (c / 8)] & (1 << (c % 8)))) {
+					/* Are we starting a range?  */
+					if (last + 1 == c && !in_range) {
+						putchar('-');
+						in_range = 1;
+					}
+					/* Have we broken a range?  */
+					else if (last + 1 != c && in_range) {
+						putchar(last);
+						in_range = 0;
+					}
+
+					if (!in_range)
+						putchar(c);
+
+					last = c;
+				}
+
+			if (in_range)
+				putchar(last);
+
+			putchar(']');
+
+			p += 1 + *p;
+		}
+			break;
+
+		case begline:
+			printf("/begline");
+			break;
+
+		case endline:
+			printf("/endline");
+			break;
+
+		case on_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/on_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case on_failure_keep_string_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/on_failure_keep_string_jump to %d", p + mcnt - start);
+			break;
+
+		case dummy_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/dummy_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case push_dummy_failure:
+			printf("/push_dummy_failure");
+			break;
+
+		case maybe_pop_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/maybe_pop_jump to %d", p + mcnt - start);
+			break;
+
+		case pop_failure_jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/pop_failure_jump to %d", p + mcnt - start);
+			break;
+
+		case jump_past_alt:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/jump_past_alt to %d", p + mcnt - start);
+			break;
+
+		case jump:
+			extract_number_and_incr(&mcnt, &p);
+			printf("/jump to %d", p + mcnt - start);
+			break;
+
+		case succeed_n:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/succeed_n to %d, %d times", p1 - start, mcnt2);
+			break;
+
+		case jump_n:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/jump_n to %d, %d times", p1 - start, mcnt2);
+			break;
+
+		case set_number_at:
+			extract_number_and_incr(&mcnt, &p);
+			p1 = p + mcnt;
+			extract_number_and_incr(&mcnt2, &p);
+			printf("/set_number_at location %d to %d", p1 - start, mcnt2);
+			break;
+
+		case wordbound:
+			printf("/wordbound");
+			break;
+
+		case notwordbound:
+			printf("/notwordbound");
+			break;
+
+		case wordbeg:
+			printf("/wordbeg");
+			break;
+
+		case wordend:
+			printf("/wordend");
+
+# ifdef emacs
+		case before_dot:
+			printf("/before_dot");
+			break;
+
+		case at_dot:
+			printf("/at_dot");
+			break;
+
+		case after_dot:
+			printf("/after_dot");
+			break;
+
+		case syntaxspec:
+			printf("/syntaxspec");
+			mcnt = *p++;
+			printf("/%d", mcnt);
+			break;
+
+		case notsyntaxspec:
+			printf("/notsyntaxspec");
+			mcnt = *p++;
+			printf("/%d", mcnt);
+			break;
+# endif							/* emacs */
+
+		case wordchar:
+			printf("/wordchar");
+			break;
+
+		case notwordchar:
+			printf("/notwordchar");
+			break;
+
+		case begbuf:
+			printf("/begbuf");
+			break;
+
+		case endbuf:
+			printf("/endbuf");
+			break;
+
+		default:
+			printf("?%d", *(p - 1));
+		}
+
+		putchar('\n');
+	}
+
+	printf("%d:\tend of pattern.\n", p - start);
+}
+
+
+void print_compiled_pattern(bufp)
+struct re_pattern_buffer *bufp;
+{
+	unsigned char *buffer = bufp->buffer;
+
+	print_partial_compiled_pattern(buffer, buffer + bufp->used);
+	printf("%ld bytes used/%ld bytes allocated.\n",
+		   bufp->used, bufp->allocated);
+
+	if (bufp->fastmap_accurate && bufp->fastmap) {
+		printf("fastmap: ");
+		print_fastmap(bufp->fastmap);
+	}
+
+	printf("re_nsub: %d\t", bufp->re_nsub);
+	printf("regs_alloc: %d\t", bufp->regs_allocated);
+	printf("can_be_null: %d\t", bufp->can_be_null);
+	printf("newline_anchor: %d\n", bufp->newline_anchor);
+	printf("no_sub: %d\t", bufp->no_sub);
+	printf("not_bol: %d\t", bufp->not_bol);
+	printf("not_eol: %d\t", bufp->not_eol);
+	printf("syntax: %lx\n", bufp->syntax);
+	/* Perhaps we should print the translate table?  */
+}
+
+
+void print_double_string(where, string1, size1, string2, size2)
+const char *where;
+const char *string1;
+const char *string2;
+int size1;
+int size2;
+{
+	int this_char;
+
+	if (where == NULL)
+		printf("(null)");
+	else {
+		if (FIRST_STRING_P(where)) {
+			for (this_char = where - string1; this_char < size1;
+				 this_char++)
+				putchar(string1[this_char]);
+
+			where = string2;
+		}
+
+		for (this_char = where - string2; this_char < size2; this_char++)
+			putchar(string2[this_char]);
+	}
+}
+
+void printchar(c)
+int c;
+{
+	putc(c, stderr);
+}
+
+#else							/* not DEBUG */
+
+# undef assert
+# define assert(e)
+
+# define DEBUG_STATEMENT(e)
+# define DEBUG_PRINT1(x)
+# define DEBUG_PRINT2(x1, x2)
+# define DEBUG_PRINT3(x1, x2, x3)
+# define DEBUG_PRINT4(x1, x2, x3, x4)
+# define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
+# define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
+
+#endif							/* not DEBUG */
+
+/* Set by `re_set_syntax' to the current regexp syntax to recognize.  Can
+   also be assigned to arbitrarily: each pattern buffer stores its own
+   syntax, so it can be changed between regex compilations.  */
+/* This has no initializer because initialized variables in Emacs
+   become read-only after dumping.  */
+reg_syntax_t re_syntax_options;
+
+
+/* Specify the precise syntax of regexps for compilation.  This provides
+   for compatibility for various utilities which historically have
+   different, incompatible syntaxes.
+
+   The argument SYNTAX is a bit mask comprised of the various bits
+   defined in regex.h.  We return the old syntax.  */
+
+reg_syntax_t re_set_syntax(syntax)
+reg_syntax_t syntax;
+{
+	reg_syntax_t ret = re_syntax_options;
+
+	re_syntax_options = syntax;
+#ifdef DEBUG
+	if (syntax & RE_DEBUG)
+		debug = 1;
+	else if (debug)				/* was on but now is not */
+		debug = 0;
+#endif							/* DEBUG */
+	return ret;
+}
+
+#ifdef _LIBC
+weak_alias(__re_set_syntax, re_set_syntax)
+#endif
+/* This table gives an error message for each of the error codes listed
+   in regex.h.  Obviously the order here has to be same as there.
+   POSIX doesn't require that we do anything for REG_NOERROR,
+   but why not be nice?  */
+static const char re_error_msgid[] = {
+#define REG_NOERROR_IDX	0
+	gettext_noop("Success")		/* REG_NOERROR */
+		"\0"
+#define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
+		gettext_noop("No match")	/* REG_NOMATCH */
+		"\0"
+#define REG_BADPAT_IDX	(REG_NOMATCH_IDX + sizeof "No match")
+		gettext_noop("Invalid regular expression")	/* REG_BADPAT */
+		"\0"
+#define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
+		gettext_noop("Invalid collation character")	/* REG_ECOLLATE */
+		"\0"
+#define REG_ECTYPE_IDX	(REG_ECOLLATE_IDX + sizeof "Invalid collation character")
+		gettext_noop("Invalid character class name")	/* REG_ECTYPE */
+		"\0"
+#define REG_EESCAPE_IDX	(REG_ECTYPE_IDX + sizeof "Invalid character class name")
+		gettext_noop("Trailing backslash")	/* REG_EESCAPE */
+		"\0"
+#define REG_ESUBREG_IDX	(REG_EESCAPE_IDX + sizeof "Trailing backslash")
+		gettext_noop("Invalid back reference")	/* REG_ESUBREG */
+		"\0"
+#define REG_EBRACK_IDX	(REG_ESUBREG_IDX + sizeof "Invalid back reference")
+		gettext_noop("Unmatched [ or [^")	/* REG_EBRACK */
+		"\0"
+#define REG_EPAREN_IDX	(REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
+		gettext_noop("Unmatched ( or \\(")	/* REG_EPAREN */
+		"\0"
+#define REG_EBRACE_IDX	(REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
+		gettext_noop("Unmatched \\{")	/* REG_EBRACE */
+		"\0"
+#define REG_BADBR_IDX	(REG_EBRACE_IDX + sizeof "Unmatched \\{")
+		gettext_noop("Invalid content of \\{\\}")	/* REG_BADBR */
+		"\0"
+#define REG_ERANGE_IDX	(REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
+		gettext_noop("Invalid range end")	/* REG_ERANGE */
+		"\0"
+#define REG_ESPACE_IDX	(REG_ERANGE_IDX + sizeof "Invalid range end")
+		gettext_noop("Memory exhausted")	/* REG_ESPACE */
+		"\0"
+#define REG_BADRPT_IDX	(REG_ESPACE_IDX + sizeof "Memory exhausted")
+		gettext_noop("Invalid preceding regular expression")	/* REG_BADRPT */
+		"\0"
+#define REG_EEND_IDX	(REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
+		gettext_noop("Premature end of regular expression")	/* REG_EEND */
+		"\0"
+#define REG_ESIZE_IDX	(REG_EEND_IDX + sizeof "Premature end of regular expression")
+		gettext_noop("Regular expression too big")	/* REG_ESIZE */
+		"\0"
+#define REG_ERPAREN_IDX	(REG_ESIZE_IDX + sizeof "Regular expression too big")
+		gettext_noop("Unmatched ) or \\)")	/* REG_ERPAREN */
+};
+
+static const size_t re_error_msgid_idx[] = {
+	REG_NOERROR_IDX,
+	REG_NOMATCH_IDX,
+	REG_BADPAT_IDX,
+	REG_ECOLLATE_IDX,
+	REG_ECTYPE_IDX,
+	REG_EESCAPE_IDX,
+	REG_ESUBREG_IDX,
+	REG_EBRACK_IDX,
+	REG_EPAREN_IDX,
+	REG_EBRACE_IDX,
+	REG_BADBR_IDX,
+	REG_ERANGE_IDX,
+	REG_ESPACE_IDX,
+	REG_BADRPT_IDX,
+	REG_EEND_IDX,
+	REG_ESIZE_IDX,
+	REG_ERPAREN_IDX
+};
+
+/* Avoiding alloca during matching, to placate r_alloc.  */
+
+/* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
+   searching and matching functions should not call alloca.  On some
+   systems, alloca is implemented in terms of malloc, and if we're
+   using the relocating allocator routines, then malloc could cause a
+   relocation, which might (if the strings being searched are in the
+   ralloc heap) shift the data out from underneath the regexp
+   routines.
+
+   Here's another reason to avoid allocation: Emacs
+   processes input from X in a signal handler; processing X input may
+   call malloc; if input arrives while a matching routine is calling
+   malloc, then we're scrod.  But Emacs can't just block input while
+   calling matching routines; then we don't notice interrupts when
+   they come in.  So, Emacs blocks input around all regexp calls
+   except the matching calls, which it leaves unprotected, in the
+   faith that they will not malloc.  */
+
+/* Normally, this is fine.  */
+#define MATCH_MAY_ALLOCATE
+
+/* When using GNU C, we are not REALLY using the C alloca, no matter
+   what config.h may say.  So don't take precautions for it.  */
+#ifdef __GNUC__
+# undef C_ALLOCA
+#endif
+
+/* The match routines may not allocate if (1) they would do it with malloc
+   and (2) it's not safe for them to use malloc.
+   Note that if REL_ALLOC is defined, matching would not use malloc for the
+   failure stack, but we would still use it for the register vectors;
+   so REL_ALLOC should not affect this.  */
+#if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
+# undef MATCH_MAY_ALLOCATE
+#endif
+
+
+/* Failure stack declarations and macros; both re_compile_fastmap and
+   re_match_2 use a failure stack.  These have to be macros because of
+   REGEX_ALLOCATE_STACK.  */
+
+
+/* Number of failure points for which to initially allocate space
+   when matching.  If this number is exceeded, we allocate more
+   space, so it is not a hard limit.  */
+#ifndef INIT_FAILURE_ALLOC
+# define INIT_FAILURE_ALLOC 5
+#endif
+
+/* Roughly the maximum number of failure points on the stack.  Would be
+   exactly that if always used MAX_FAILURE_ITEMS items each time we failed.
+   This is a variable only so users of regex can assign to it; we never
+   change it ourselves.  */
+
+#ifdef INT_IS_16BIT
+
+# if defined MATCH_MAY_ALLOCATE
+/* 4400 was enough to cause a crash on Alpha OSF/1,
+   whose default stack limit is 2mb.  */
+long int re_max_failures = 4000;
+# else
+long int re_max_failures = 2000;
+# endif
+
+union fail_stack_elt {
+	unsigned char *pointer;
+	long int integer;
+};
+
+typedef union fail_stack_elt fail_stack_elt_t;
+
+typedef struct {
+	fail_stack_elt_t *stack;
+	unsigned long int size;
+	unsigned long int avail;	/* Offset of next open position.  */
+} fail_stack_type;
+
+#else							/* not INT_IS_16BIT */
+
+# if defined MATCH_MAY_ALLOCATE
+/* 4400 was enough to cause a crash on Alpha OSF/1,
+   whose default stack limit is 2mb.  */
+int re_max_failures = 20000;
+# else
+int re_max_failures = 2000;
+# endif
+
+union fail_stack_elt {
+	unsigned char *pointer;
+	int integer;
+};
+
+typedef union fail_stack_elt fail_stack_elt_t;
+
+typedef struct {
+	fail_stack_elt_t *stack;
+	unsigned size;
+	unsigned avail;				/* Offset of next open position.  */
+} fail_stack_type;
+
+#endif							/* INT_IS_16BIT */
+
+#define FAIL_STACK_EMPTY()     (fail_stack.avail == 0)
+#define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
+#define FAIL_STACK_FULL()      (fail_stack.avail == fail_stack.size)
+
+
+/* Define macros to initialize and free the failure stack.
+   Do `return -2' if the alloc fails.  */
+
+#ifdef MATCH_MAY_ALLOCATE
+# define INIT_FAIL_STACK()						\
+  do {									\
+    fail_stack.stack = (fail_stack_elt_t *)				\
+      REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
+									\
+    if (fail_stack.stack == NULL)					\
+      return -2;							\
+									\
+    fail_stack.size = INIT_FAILURE_ALLOC;				\
+    fail_stack.avail = 0;						\
+  } while (0)
+
+# define RESET_FAIL_STACK()  REGEX_FREE_STACK (fail_stack.stack)
+#else
+# define INIT_FAIL_STACK()						\
+  do {									\
+    fail_stack.avail = 0;						\
+  } while (0)
+
+# define RESET_FAIL_STACK()
+#endif
+
+
+/* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
+
+   Return 1 if succeeds, and 0 if either ran out of memory
+   allocating space for it or it was already too large.
+
+   REGEX_REALLOCATE_STACK requires `destination' be declared.   */
+
+#define DOUBLE_FAIL_STACK(fail_stack)					\
+  ((fail_stack).size > (unsigned) (re_max_failures * MAX_FAILURE_ITEMS)	\
+   ? 0									\
+   : ((fail_stack).stack = (fail_stack_elt_t *)				\
+        REGEX_REALLOCATE_STACK ((fail_stack).stack, 			\
+          (fail_stack).size * sizeof (fail_stack_elt_t),		\
+          ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)),	\
+									\
+      (fail_stack).stack == NULL					\
+      ? 0								\
+      : ((fail_stack).size <<= 1, 					\
+         1)))
+
+
+/* Push pointer POINTER on FAIL_STACK.
+   Return 1 if was able to do so and 0 if ran out of memory allocating
+   space to do so.  */
+#define PUSH_PATTERN_OP(POINTER, FAIL_STACK)				\
+  ((FAIL_STACK_FULL ()							\
+    && !DOUBLE_FAIL_STACK (FAIL_STACK))					\
+   ? 0									\
+   : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER,	\
+      1))
+
+/* Push a pointer value onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_POINTER(item)					\
+  fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
+
+/* This pushes an integer-valued item onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_INT(item)					\
+  fail_stack.stack[fail_stack.avail++].integer = (item)
+
+/* Push a fail_stack_elt_t value onto the failure stack.
+   Assumes the variable `fail_stack'.  Probably should only
+   be called from within `PUSH_FAILURE_POINT'.  */
+#define PUSH_FAILURE_ELT(item)					\
+  fail_stack.stack[fail_stack.avail++] =  (item)
+
+/* These three POP... operations complement the three PUSH... operations.
+   All assume that `fail_stack' is nonempty.  */
+#define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
+#define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
+#define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
+
+/* Used to omit pushing failure point id's when we're not debugging.  */
+#ifdef DEBUG
+# define DEBUG_PUSH PUSH_FAILURE_INT
+# define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
+#else
+# define DEBUG_PUSH(item)
+# define DEBUG_POP(item_addr)
+#endif
+
+
+/* Push the information about the state we will need
+   if we ever fail back to it.
+
+   Requires variables fail_stack, regstart, regend, reg_info, and
+   num_regs_pushed be declared.  DOUBLE_FAIL_STACK requires `destination'
+   be declared.
+
+   Does `return FAILURE_CODE' if runs out of memory.  */
+
+#define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code)	\
+  do {									\
+    char *destination;							\
+    /* Must be int, so when we don't save any registers, the arithmetic	\
+       of 0 + -1 isn't done as unsigned.  */				\
+    /* Can't be int, since there is not a shred of a guarantee that int	\
+       is wide enough to hold a value of something to which pointer can	\
+       be assigned */							\
+    active_reg_t this_reg;						\
+    									\
+    DEBUG_STATEMENT (failure_id++);					\
+    DEBUG_STATEMENT (nfailure_points_pushed++);				\
+    DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id);		\
+    DEBUG_PRINT2 ("  Before push, next avail: %d\n", (fail_stack).avail);\
+    DEBUG_PRINT2 ("                     size: %d\n", (fail_stack).size);\
+									\
+    DEBUG_PRINT2 ("  slots needed: %ld\n", NUM_FAILURE_ITEMS);		\
+    DEBUG_PRINT2 ("     available: %d\n", REMAINING_AVAIL_SLOTS);	\
+									\
+    /* Ensure we have enough space allocated for what we will push.  */	\
+    while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS)			\
+      {									\
+        if (!DOUBLE_FAIL_STACK (fail_stack))				\
+          return failure_code;						\
+									\
+        DEBUG_PRINT2 ("\n  Doubled stack; size now: %d\n",		\
+		       (fail_stack).size);				\
+        DEBUG_PRINT2 ("  slots available: %d\n", REMAINING_AVAIL_SLOTS);\
+      }									\
+									\
+    /* Push the info, starting with the registers.  */			\
+    DEBUG_PRINT1 ("\n");						\
+									\
+    if (1)								\
+      for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
+	   this_reg++)							\
+	{								\
+	  DEBUG_PRINT2 ("  Pushing reg: %lu\n", this_reg);		\
+	  DEBUG_STATEMENT (num_regs_pushed++);				\
+									\
+	  DEBUG_PRINT2 ("    start: %p\n", regstart[this_reg]);		\
+	  PUSH_FAILURE_POINTER (regstart[this_reg]);			\
+									\
+	  DEBUG_PRINT2 ("    end: %p\n", regend[this_reg]);		\
+	  PUSH_FAILURE_POINTER (regend[this_reg]);			\
+									\
+	  DEBUG_PRINT2 ("    info: %p\n      ",				\
+			reg_info[this_reg].word.pointer);		\
+	  DEBUG_PRINT2 (" match_null=%d",				\
+			REG_MATCH_NULL_STRING_P (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" matched_something=%d",			\
+			MATCHED_SOMETHING (reg_info[this_reg]));	\
+	  DEBUG_PRINT2 (" ever_matched=%d",				\
+			EVER_MATCHED_SOMETHING (reg_info[this_reg]));	\
+	  DEBUG_PRINT1 ("\n");						\
+	  PUSH_FAILURE_ELT (reg_info[this_reg].word);			\
+	}								\
+									\
+    DEBUG_PRINT2 ("  Pushing  low active reg: %ld\n", lowest_active_reg);\
+    PUSH_FAILURE_INT (lowest_active_reg);				\
+									\
+    DEBUG_PRINT2 ("  Pushing high active reg: %ld\n", highest_active_reg);\
+    PUSH_FAILURE_INT (highest_active_reg);				\
+									\
+    DEBUG_PRINT2 ("  Pushing pattern %p:\n", pattern_place);		\
+    DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend);		\
+    PUSH_FAILURE_POINTER (pattern_place);				\
+									\
+    DEBUG_PRINT2 ("  Pushing string %p: `", string_place);		\
+    DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2,   \
+				 size2);				\
+    DEBUG_PRINT1 ("'\n");						\
+    PUSH_FAILURE_POINTER (string_place);				\
+									\
+    DEBUG_PRINT2 ("  Pushing failure id: %u\n", failure_id);		\
+    DEBUG_PUSH (failure_id);						\
+  } while (0)
+
+/* This is the number of items that are pushed and popped on the stack
+   for each register.  */
+#define NUM_REG_ITEMS  3
+
+/* Individual items aside from the registers.  */
+#ifdef DEBUG
+# define NUM_NONREG_ITEMS 5		/* Includes failure point id.  */
+#else
+# define NUM_NONREG_ITEMS 4
+#endif
+
+/* We push at most this many items on the stack.  */
+/* We used to use (num_regs - 1), which is the number of registers
+   this regexp will save; but that was changed to 5
+   to avoid stack overflow for a regexp with lots of parens.  */
+#define MAX_FAILURE_ITEMS (5 * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
+
+/* We actually push this many items.  */
+#define NUM_FAILURE_ITEMS				\
+  (((0							\
+     ? 0 : highest_active_reg - lowest_active_reg + 1)	\
+    * NUM_REG_ITEMS)					\
+   + NUM_NONREG_ITEMS)
+
+/* How many items can still be added to the stack without overflowing it.  */
+#define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
+
+
+/* Pops what PUSH_FAIL_STACK pushes.
+
+   We restore into the parameters, all of which should be lvalues:
+     STR -- the saved data position.
+     PAT -- the saved pattern position.
+     LOW_REG, HIGH_REG -- the highest and lowest active registers.
+     REGSTART, REGEND -- arrays of string positions.
+     REG_INFO -- array of information about each subexpression.
+
+   Also assumes the variables `fail_stack' and (if debugging), `bufp',
+   `pend', `string1', `size1', `string2', and `size2'.  */
+
+#define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
+{									\
+  DEBUG_STATEMENT (unsigned failure_id;)				\
+  active_reg_t this_reg;						\
+  const unsigned char *string_temp;					\
+									\
+  assert (!FAIL_STACK_EMPTY ());					\
+									\
+  /* Remove failure points and point to how many regs pushed.  */	\
+  DEBUG_PRINT1 ("POP_FAILURE_POINT:\n");				\
+  DEBUG_PRINT2 ("  Before pop, next avail: %d\n", fail_stack.avail);	\
+  DEBUG_PRINT2 ("                    size: %d\n", fail_stack.size);	\
+									\
+  assert (fail_stack.avail >= NUM_NONREG_ITEMS);			\
+									\
+  DEBUG_POP (&failure_id);						\
+  DEBUG_PRINT2 ("  Popping failure id: %u\n", failure_id);		\
+									\
+  /* If the saved string location is NULL, it came from an		\
+     on_failure_keep_string_jump opcode, and we want to throw away the	\
+     saved NULL, thus retaining our current position in the string.  */	\
+  string_temp = POP_FAILURE_POINTER ();					\
+  if (string_temp != NULL)						\
+    str = (const char *) string_temp;					\
+									\
+  DEBUG_PRINT2 ("  Popping string %p: `", str);				\
+  DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2);	\
+  DEBUG_PRINT1 ("'\n");							\
+									\
+  pat = (unsigned char *) POP_FAILURE_POINTER ();			\
+  DEBUG_PRINT2 ("  Popping pattern %p:\n", pat);			\
+  DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend);			\
+									\
+  /* Restore register info.  */						\
+  high_reg = (active_reg_t) POP_FAILURE_INT ();				\
+  DEBUG_PRINT2 ("  Popping high active reg: %ld\n", high_reg);		\
+									\
+  low_reg = (active_reg_t) POP_FAILURE_INT ();				\
+  DEBUG_PRINT2 ("  Popping  low active reg: %ld\n", low_reg);		\
+									\
+  if (1)								\
+    for (this_reg = high_reg; this_reg >= low_reg; this_reg--)		\
+      {									\
+	DEBUG_PRINT2 ("    Popping reg: %ld\n", this_reg);		\
+									\
+	reg_info[this_reg].word = POP_FAILURE_ELT ();			\
+	DEBUG_PRINT2 ("      info: %p\n",				\
+		      reg_info[this_reg].word.pointer);			\
+									\
+	regend[this_reg] = (const char *) POP_FAILURE_POINTER ();	\
+	DEBUG_PRINT2 ("      end: %p\n", regend[this_reg]);		\
+									\
+	regstart[this_reg] = (const char *) POP_FAILURE_POINTER ();	\
+	DEBUG_PRINT2 ("      start: %p\n", regstart[this_reg]);		\
+      }									\
+  else									\
+    {									\
+      for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
+	{								\
+	  reg_info[this_reg].word.integer = 0;				\
+	  regend[this_reg] = 0;						\
+	  regstart[this_reg] = 0;					\
+	}								\
+      highest_active_reg = high_reg;					\
+    }									\
+									\
+  set_regs_matched_done = 0;						\
+  DEBUG_STATEMENT (nfailure_points_popped++);				\
+}								/* POP_FAILURE_POINT */
+
+
+
+/* Structure for per-register (a.k.a. per-group) information.
+   Other register information, such as the
+   starting and ending positions (which are addresses), and the list of
+   inner groups (which is a bits list) are maintained in separate
+   variables.
+
+   We are making a (strictly speaking) nonportable assumption here: that
+   the compiler will pack our bit fields into something that fits into
+   the type of `word', i.e., is something that fits into one item on the
+   failure stack.  */
+
+
+/* Declarations and macros for re_match_2.  */
+
+typedef union {
+	fail_stack_elt_t word;
+	struct {
+		/* This field is one if this group can match the empty string,
+		   zero if not.  If not yet determined,  `MATCH_NULL_UNSET_VALUE'.  */
+#define MATCH_NULL_UNSET_VALUE 3
+		unsigned match_null_string_p:2;
+		unsigned is_active:1;
+		unsigned matched_something:1;
+		unsigned ever_matched_something:1;
+	} bits;
+} register_info_type;
+
+#define REG_MATCH_NULL_STRING_P(R)  ((R).bits.match_null_string_p)
+#define IS_ACTIVE(R)  ((R).bits.is_active)
+#define MATCHED_SOMETHING(R)  ((R).bits.matched_something)
+#define EVER_MATCHED_SOMETHING(R)  ((R).bits.ever_matched_something)
+
+
+/* Call this when have matched a real character; it sets `matched' flags
+   for the subexpressions which we are currently inside.  Also records
+   that those subexprs have matched.  */
+#define SET_REGS_MATCHED()						\
+  do									\
+    {									\
+      if (!set_regs_matched_done)					\
+	{								\
+	  active_reg_t r;						\
+	  set_regs_matched_done = 1;					\
+	  for (r = lowest_active_reg; r <= highest_active_reg; r++)	\
+	    {								\
+	      MATCHED_SOMETHING (reg_info[r])				\
+		= EVER_MATCHED_SOMETHING (reg_info[r])			\
+		= 1;							\
+	    }								\
+	}								\
+    }									\
+  while (0)
+
+/* Registers are set to a sentinel when they haven't yet matched.  */
+static char reg_unset_dummy;
+
+#define REG_UNSET_VALUE (&reg_unset_dummy)
+#define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
+
+/* Subroutine declarations and macros for regex_compile.  */
+
+static reg_errcode_t regex_compile
+_RE_ARGS(
+		 (const char *pattern, size_t size, reg_syntax_t syntax,
+		  struct re_pattern_buffer * bufp));
+static void store_op1
+
+_RE_ARGS((re_opcode_t op, unsigned char *loc, int arg));
+static void store_op2
+_RE_ARGS((re_opcode_t op, unsigned char *loc, int arg1, int arg2));
+static void insert_op1
+_RE_ARGS(
+
+		 (re_opcode_t op, unsigned char *loc, int arg,
+		  unsigned char *end));
+static void insert_op2
+_RE_ARGS(
+		 (re_opcode_t op, unsigned char *loc, int arg1, int arg2,
+
+		  unsigned char *end));
+static boolean at_begline_loc_p
+_RE_ARGS((const char *pattern, const char *p, reg_syntax_t syntax));
+static boolean at_endline_loc_p
+_RE_ARGS((const char *p, const char *pend, reg_syntax_t syntax));
+static reg_errcode_t compile_range
+_RE_ARGS(
+		 (const char **p_ptr, const char *pend, char *translate,
+		  reg_syntax_t syntax, unsigned char *b));
+
+/* Fetch the next character in the uncompiled pattern---translating it
+   if necessary.  Also cast from a signed character in the constant
+   string passed to us by the user to an unsigned char that we can use
+   as an array index (in, e.g., `translate').  */
+#ifndef PATFETCH
+# define PATFETCH(c)							\
+  do {if (p == pend) return REG_EEND;					\
+    c = (unsigned char) *p++;						\
+    if (translate) c = (unsigned char) translate[c];			\
+  } while (0)
+#endif
+
+/* Fetch the next character in the uncompiled pattern, with no
+   translation.  */
+#define PATFETCH_RAW(c)							\
+  do {if (p == pend) return REG_EEND;					\
+    c = (unsigned char) *p++; 						\
+  } while (0)
+
+/* Go backwards one character in the pattern.  */
+#define PATUNFETCH p--
+
+
+/* If `translate' is non-null, return translate[D], else just D.  We
+   cast the subscript to translate because some data is declared as
+   `char *', to avoid warnings when a string constant is passed.  But
+   when we use a character as a subscript we must make it unsigned.  */
+#ifndef TRANSLATE
+# define TRANSLATE(d) \
+  (translate ? (char) translate[(unsigned char) (d)] : (d))
+#endif
+
+
+/* Macros for outputting the compiled pattern into `buffer'.  */
+
+/* If the buffer isn't allocated when it comes in, use this.  */
+#define INIT_BUF_SIZE  32
+
+/* Make sure we have at least N more bytes of space in buffer.  */
+#define GET_BUFFER_SPACE(n)						\
+    while ((unsigned long) (b - bufp->buffer + (n)) > bufp->allocated)	\
+      EXTEND_BUFFER ()
+
+/* Make sure we have one more byte of buffer space and then add C to it.  */
+#define BUF_PUSH(c)							\
+  do {									\
+    GET_BUFFER_SPACE (1);						\
+    *b++ = (unsigned char) (c);						\
+  } while (0)
+
+
+/* Ensure we have two more bytes of buffer space and then append C1 and C2.  */
+#define BUF_PUSH_2(c1, c2)						\
+  do {									\
+    GET_BUFFER_SPACE (2);						\
+    *b++ = (unsigned char) (c1);					\
+    *b++ = (unsigned char) (c2);					\
+  } while (0)
+
+
+/* As with BUF_PUSH_2, except for three bytes.  */
+#define BUF_PUSH_3(c1, c2, c3)						\
+  do {									\
+    GET_BUFFER_SPACE (3);						\
+    *b++ = (unsigned char) (c1);					\
+    *b++ = (unsigned char) (c2);					\
+    *b++ = (unsigned char) (c3);					\
+  } while (0)
+
+
+/* Store a jump with opcode OP at LOC to location TO.  We store a
+   relative address offset by the three bytes the jump itself occupies.  */
+#define STORE_JUMP(op, loc, to) \
+  store_op1 (op, loc, (int) ((to) - (loc) - 3))
+
+/* Likewise, for a two-argument jump.  */
+#define STORE_JUMP2(op, loc, to, arg) \
+  store_op2 (op, loc, (int) ((to) - (loc) - 3), arg)
+
+/* Like `STORE_JUMP', but for inserting.  Assume `b' is the buffer end.  */
+#define INSERT_JUMP(op, loc, to) \
+  insert_op1 (op, loc, (int) ((to) - (loc) - 3), b)
+
+/* Like `STORE_JUMP2', but for inserting.  Assume `b' is the buffer end.  */
+#define INSERT_JUMP2(op, loc, to, arg) \
+  insert_op2 (op, loc, (int) ((to) - (loc) - 3), arg, b)
+
+
+/* This is not an arbitrary limit: the arguments which represent offsets
+   into the pattern are two bytes long.  So if 2^16 bytes turns out to
+   be too small, many things would have to change.  */
+/* Any other compiler which, like MSC, has allocation limit below 2^16
+   bytes will have to use approach similar to what was done below for
+   MSC and drop MAX_BUF_SIZE a bit.  Otherwise you may end up
+   reallocating to 0 bytes.  Such thing is not going to work too well.
+   You have been warned!!  */
+#if defined _MSC_VER  && !defined WIN32
+/* Microsoft C 16-bit versions limit malloc to approx 65512 bytes.
+   The REALLOC define eliminates a flurry of conversion warnings,
+   but is not required. */
+# define MAX_BUF_SIZE  65500L
+# define REALLOC(p,s) realloc ((p), (size_t) (s))
+#else
+# define MAX_BUF_SIZE (1L << 16)
+# define REALLOC(p,s) realloc ((p), (s))
+#endif
+
+/* Extend the buffer by twice its current size via realloc and
+   reset the pointers that pointed into the old block to point to the
+   correct places in the new one.  If extending the buffer results in it
+   being larger than MAX_BUF_SIZE, then flag memory exhausted.  */
+#define EXTEND_BUFFER()							\
+  do { 									\
+    unsigned char *old_buffer = bufp->buffer;				\
+    if (bufp->allocated == MAX_BUF_SIZE) 				\
+      return REG_ESIZE;							\
+    bufp->allocated <<= 1;						\
+    if (bufp->allocated > MAX_BUF_SIZE)					\
+      bufp->allocated = MAX_BUF_SIZE; 					\
+    bufp->buffer = (unsigned char *) REALLOC (bufp->buffer, bufp->allocated);\
+    if (bufp->buffer == NULL)						\
+      return REG_ESPACE;						\
+    /* If the buffer moved, move all the pointers into it.  */		\
+    if (old_buffer != bufp->buffer)					\
+      {									\
+        b = (b - old_buffer) + bufp->buffer;				\
+        begalt = (begalt - old_buffer) + bufp->buffer;			\
+        if (fixup_alt_jump)						\
+          fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
+        if (laststart)							\
+          laststart = (laststart - old_buffer) + bufp->buffer;		\
+        if (pending_exact)						\
+          pending_exact = (pending_exact - old_buffer) + bufp->buffer;	\
+      }									\
+  } while (0)
+
+
+/* Since we have one byte reserved for the register number argument to
+   {start,stop}_memory, the maximum number of groups we can report
+   things about is what fits in that byte.  */
+#define MAX_REGNUM 255
+
+/* But patterns can have more than `MAX_REGNUM' registers.  We just
+   ignore the excess.  */
+typedef unsigned regnum_t;
+
+
+/* Macros for the compile stack.  */
+
+/* Since offsets can go either forwards or backwards, this type needs to
+   be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1.  */
+/* int may be not enough when sizeof(int) == 2.  */
+typedef long pattern_offset_t;
+
+typedef struct {
+	pattern_offset_t begalt_offset;
+	pattern_offset_t fixup_alt_jump;
+	pattern_offset_t inner_group_offset;
+	pattern_offset_t laststart_offset;
+	regnum_t regnum;
+} compile_stack_elt_t;
+
+
+typedef struct {
+	compile_stack_elt_t *stack;
+	unsigned size;
+	unsigned avail;				/* Offset of next open position.  */
+} compile_stack_type;
+
+
+#define INIT_COMPILE_STACK_SIZE 32
+
+#define COMPILE_STACK_EMPTY  (compile_stack.avail == 0)
+#define COMPILE_STACK_FULL  (compile_stack.avail == compile_stack.size)
+
+/* The next available element.  */
+#define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
+
+
+/* Set the bit for character C in a list.  */
+#define SET_LIST_BIT(c)                               \
+  (b[((unsigned char) (c)) / BYTEWIDTH]               \
+   |= 1 << (((unsigned char) c) % BYTEWIDTH))
+
+
+/* Get the next unsigned number in the uncompiled pattern.  */
+#define GET_UNSIGNED_NUMBER(num) 					\
+  { if (p != pend)							\
+     {									\
+       PATFETCH (c); 							\
+       while ('0' <= c && c <= '9')					\
+         { 								\
+           if (num < 0)							\
+              num = 0;							\
+           num = num * 10 + c - '0'; 					\
+           if (p == pend) 						\
+              break; 							\
+           PATFETCH (c);						\
+         } 								\
+       } 								\
+    }
+
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+/* The GNU C library provides support for user-defined character classes
+   and the functions from ISO C amendement 1.  */
+# ifdef CHARCLASS_NAME_MAX
+#  define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
+# else
+/* This shouldn't happen but some implementation might still have this
+   problem.  Use a reasonable default value.  */
+#  define CHAR_CLASS_MAX_LENGTH 256
+# endif
+
+# ifdef _LIBC
+#  define IS_CHAR_CLASS(string) __wctype (string)
+# else
+#  define IS_CHAR_CLASS(string) wctype (string)
+# endif
+#else
+# define CHAR_CLASS_MAX_LENGTH  6	/* Namely, `xdigit'.  */
+
+# define IS_CHAR_CLASS(string)						\
+   (STREQ (string, "alpha") || STREQ (string, "upper")			\
+    || STREQ (string, "lower") || STREQ (string, "digit")		\
+    || STREQ (string, "alnum") || STREQ (string, "xdigit")		\
+    || STREQ (string, "space") || STREQ (string, "print")		\
+    || STREQ (string, "punct") || STREQ (string, "graph")		\
+    || STREQ (string, "cntrl") || STREQ (string, "blank"))
+#endif
+
+#ifndef MATCH_MAY_ALLOCATE
+
+/* If we cannot allocate large objects within re_match_2_internal,
+   we make the fail stack and register vectors global.
+   The fail stack, we grow to the maximum size when a regexp
+   is compiled.
+   The register vectors, we adjust in size each time we
+   compile a regexp, according to the number of registers it needs.  */
+
+static fail_stack_type fail_stack;
+
+/* Size with which the following vectors are currently allocated.
+   That is so we can make them bigger as needed,
+   but never make them smaller.  */
+static int regs_allocated_size;
+
+static const char **regstart, **regend;
+static const char **old_regstart, **old_regend;
+static const char **best_regstart, **best_regend;
+static register_info_type *reg_info;
+static const char **reg_dummy;
+static register_info_type *reg_info_dummy;
+
+/* Make the register vectors big enough for NUM_REGS registers,
+   but don't make them smaller.  */
+
+static regex_grow_registers(num_regs)
+int num_regs;
+{
+	if (num_regs > regs_allocated_size) {
+		RETALLOC_IF(regstart, num_regs, const char *);
+		RETALLOC_IF(regend, num_regs, const char *);
+		RETALLOC_IF(old_regstart, num_regs, const char *);
+		RETALLOC_IF(old_regend, num_regs, const char *);
+		RETALLOC_IF(best_regstart, num_regs, const char *);
+		RETALLOC_IF(best_regend, num_regs, const char *);
+
+		RETALLOC_IF(reg_info, num_regs, register_info_type);
+		RETALLOC_IF(reg_dummy, num_regs, const char *);
+
+		RETALLOC_IF(reg_info_dummy, num_regs, register_info_type);
+
+		regs_allocated_size = num_regs;
+	}
+}
+
+#endif							/* not MATCH_MAY_ALLOCATE */
+
+static boolean group_in_compile_stack _RE_ARGS((compile_stack_type
+												compile_stack,
+
+												regnum_t regnum));
+
+/* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
+   Returns one of error codes defined in `regex.h', or zero for success.
+
+   Assumes the `allocated' (and perhaps `buffer') and `translate'
+   fields are set in BUFP on entry.
+
+   If it succeeds, results are put in BUFP (if it returns an error, the
+   contents of BUFP are undefined):
+     `buffer' is the compiled pattern;
+     `syntax' is set to SYNTAX;
+     `used' is set to the length of the compiled pattern;
+     `fastmap_accurate' is zero;
+     `re_nsub' is the number of subexpressions in PATTERN;
+     `not_bol' and `not_eol' are zero;
+
+   The `fastmap' and `newline_anchor' fields are neither
+   examined nor set.  */
+
+/* Return, freeing storage we allocated.  */
+#define FREE_STACK_RETURN(value)		\
+  return (free (compile_stack.stack), value)
+
+static reg_errcode_t regex_compile(pattern, size, syntax, bufp)
+const char *pattern;
+size_t size;
+reg_syntax_t syntax;
+struct re_pattern_buffer *bufp;
+{
+	/* We fetch characters from PATTERN here.  Even though PATTERN is
+	   `char *' (i.e., signed), we declare these variables as unsigned, so
+	   they can be reliably used as array indices.  */
+	register unsigned char c, c1;
+
+	/* A random temporary spot in PATTERN.  */
+	const char *p1;
+
+	/* Points to the end of the buffer, where we should append.  */
+	register unsigned char *b;
+
+	/* Keeps track of unclosed groups.  */
+	compile_stack_type compile_stack;
+
+	/* Points to the current (ending) position in the pattern.  */
+	const char *p = pattern;
+	const char *pend = pattern + size;
+
+	/* How to translate the characters in the pattern.  */
+	RE_TRANSLATE_TYPE translate = bufp->translate;
+
+	/* Address of the count-byte of the most recently inserted `exactn'
+	   command.  This makes it possible to tell if a new exact-match
+	   character can be added to that command or if the character requires
+	   a new `exactn' command.  */
+	unsigned char *pending_exact = 0;
+
+	/* Address of start of the most recently finished expression.
+	   This tells, e.g., postfix * where to find the start of its
+	   operand.  Reset at the beginning of groups and alternatives.  */
+	unsigned char *laststart = 0;
+
+	/* Address of beginning of regexp, or inside of last group.  */
+	unsigned char *begalt;
+
+	/* Place in the uncompiled pattern (i.e., the {) to
+	   which to go back if the interval is invalid.  */
+	const char *beg_interval;
+
+	/* Address of the place where a forward jump should go to the end of
+	   the containing expression.  Each alternative of an `or' -- except the
+	   last -- ends with a forward jump of this sort.  */
+	unsigned char *fixup_alt_jump = 0;
+
+	/* Counts open-groups as they are encountered.  Remembered for the
+	   matching close-group on the compile stack, so the same register
+	   number is put in the stop_memory as the start_memory.  */
+	regnum_t regnum = 0;
+
+#ifdef DEBUG
+	DEBUG_PRINT1("\nCompiling pattern: ");
+	if (debug) {
+		unsigned debug_count;
+
+		for (debug_count = 0; debug_count < size; debug_count++)
+			putchar(pattern[debug_count]);
+		putchar('\n');
+	}
+#endif							/* DEBUG */
+
+	/* Initialize the compile stack.  */
+	compile_stack.stack =
+		TALLOC(INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
+	if (compile_stack.stack == NULL)
+		return REG_ESPACE;
+
+	compile_stack.size = INIT_COMPILE_STACK_SIZE;
+	compile_stack.avail = 0;
+
+	/* Initialize the pattern buffer.  */
+	bufp->syntax = syntax;
+	bufp->fastmap_accurate = 0;
+	bufp->not_bol = bufp->not_eol = 0;
+
+	/* Set `used' to zero, so that if we return an error, the pattern
+	   printer (for debugging) will think there's no pattern.  We reset it
+	   at the end.  */
+	bufp->used = 0;
+
+	/* Always count groups, whether or not bufp->no_sub is set.  */
+	bufp->re_nsub = 0;
+
+#if !defined emacs && !defined SYNTAX_TABLE
+	/* Initialize the syntax table.  */
+	init_syntax_once();
+#endif
+
+	if (bufp->allocated == 0) {
+		if (bufp->buffer) {		/* If zero allocated, but buffer is non-null, try to realloc
+								   enough space.  This loses if buffer's address is bogus, but
+								   that is the user's responsibility.  */
+			RETALLOC(bufp->buffer, INIT_BUF_SIZE, unsigned char);
+		} else {				/* Caller did not allocate a buffer.  Do it for them.  */
+			bufp->buffer = TALLOC(INIT_BUF_SIZE, unsigned char);
+		}
+		if (!bufp->buffer)
+			FREE_STACK_RETURN(REG_ESPACE);
+
+		bufp->allocated = INIT_BUF_SIZE;
+	}
+
+	begalt = b = bufp->buffer;
+
+	/* Loop through the uncompiled pattern until we're at the end.  */
+	while (p != pend) {
+		PATFETCH(c);
+
+		switch (c) {
+		case '^':
+		{
+			if (				/* If at start of pattern, it's an operator.  */
+				   p == pattern + 1
+				   /* If context independent, it's an operator.  */
+				   || syntax & RE_CONTEXT_INDEP_ANCHORS
+				   /* Otherwise, depends on what's come before.  */
+				   || at_begline_loc_p(pattern, p, syntax))
+				BUF_PUSH(begline);
+			else
+				goto normal_char;
+		}
+			break;
+
+
+		case '$':
+		{
+			if (				/* If at end of pattern, it's an operator.  */
+				   p == pend
+				   /* If context independent, it's an operator.  */
+				   || syntax & RE_CONTEXT_INDEP_ANCHORS
+				   /* Otherwise, depends on what's next.  */
+				   || at_endline_loc_p(p, pend, syntax))
+				BUF_PUSH(endline);
+			else
+				goto normal_char;
+		}
+			break;
+
+
+		case '+':
+		case '?':
+			if ((syntax & RE_BK_PLUS_QM)
+				|| (syntax & RE_LIMITED_OPS))
+				goto normal_char;
+		  handle_plus:
+		case '*':
+			/* If there is no previous pattern... */
+			if (!laststart) {
+				if (syntax & RE_CONTEXT_INVALID_OPS)
+					FREE_STACK_RETURN(REG_BADRPT);
+				else if (!(syntax & RE_CONTEXT_INDEP_OPS))
+					goto normal_char;
+			}
+
+			{
+				/* Are we optimizing this jump?  */
+				boolean keep_string_p = false;
+
+				/* 1 means zero (many) matches is allowed.  */
+				char zero_times_ok = 0, many_times_ok = 0;
+
+				/* If there is a sequence of repetition chars, collapse it
+				   down to just one (the right one).  We can't combine
+				   interval operators with these because of, e.g., `a{2}*',
+				   which should only match an even number of `a's.  */
+
+				for (;;) {
+					zero_times_ok |= c != '+';
+					many_times_ok |= c != '?';
+
+					if (p == pend)
+						break;
+
+					PATFETCH(c);
+
+					if (c == '*'
+						|| (!(syntax & RE_BK_PLUS_QM)
+							&& (c == '+' || c == '?')));
+
+					else if (syntax & RE_BK_PLUS_QM && c == '\\') {
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EESCAPE);
+
+						PATFETCH(c1);
+						if (!(c1 == '+' || c1 == '?')) {
+							PATUNFETCH;
+							PATUNFETCH;
+							break;
+						}
+
+						c = c1;
+					} else {
+						PATUNFETCH;
+						break;
+					}
+
+					/* If we get here, we found another repeat character.  */
+				}
+
+				/* Star, etc. applied to an empty pattern is equivalent
+				   to an empty pattern.  */
+				if (!laststart)
+					break;
+
+				/* Now we know whether or not zero matches is allowed
+				   and also whether or not two or more matches is allowed.  */
+				if (many_times_ok) {	/* More than one repetition is allowed, so put in at the
+										   end a backward relative jump from `b' to before the next
+										   jump we're going to put in below (which jumps from
+										   laststart to after this jump).
+
+										   But if we are at the `*' in the exact sequence `.*\n',
+										   insert an unconditional jump backwards to the .,
+										   instead of the beginning of the loop.  This way we only
+										   push a failure point once, instead of every time
+										   through the loop.  */
+					assert(p - 1 > pattern);
+
+					/* Allocate the space for the jump.  */
+					GET_BUFFER_SPACE(3);
+
+					/* We know we are not at the first character of the pattern,
+					   because laststart was nonzero.  And we've already
+					   incremented `p', by the way, to be the character after
+					   the `*'.  Do we have to do something analogous here
+					   for null bytes, because of RE_DOT_NOT_NULL?  */
+					if (TRANSLATE(*(p - 2)) == TRANSLATE('.')
+						&& zero_times_ok
+						&& p < pend && TRANSLATE(*p) == TRANSLATE('\n')
+						&& !(syntax & RE_DOT_NEWLINE)) {	/* We have .*\n.  */
+						STORE_JUMP(jump, b, laststart);
+						keep_string_p = true;
+					} else
+						/* Anything else.  */
+						STORE_JUMP(maybe_pop_jump, b, laststart - 3);
+
+					/* We've added more stuff to the buffer.  */
+					b += 3;
+				}
+
+				/* On failure, jump from laststart to b + 3, which will be the
+				   end of the buffer after this jump is inserted.  */
+				GET_BUFFER_SPACE(3);
+				INSERT_JUMP(keep_string_p ? on_failure_keep_string_jump
+							: on_failure_jump, laststart, b + 3);
+				pending_exact = 0;
+				b += 3;
+
+				if (!zero_times_ok) {
+					/* At least one repetition is required, so insert a
+					   `dummy_failure_jump' before the initial
+					   `on_failure_jump' instruction of the loop. This
+					   effects a skip over that instruction the first time
+					   we hit that loop.  */
+					GET_BUFFER_SPACE(3);
+					INSERT_JUMP(dummy_failure_jump, laststart,
+								laststart + 6);
+					b += 3;
+				}
+			}
+			break;
+
+
+		case '.':
+			laststart = b;
+			BUF_PUSH(anychar);
+			break;
+
+
+		case '[':
+		{
+			boolean had_char_class = false;
+
+			if (p == pend)
+				FREE_STACK_RETURN(REG_EBRACK);
+
+			/* Ensure that we have enough space to push a charset: the
+			   opcode, the length count, and the bitset; 34 bytes in all.  */
+			GET_BUFFER_SPACE(34);
+
+			laststart = b;
+
+			/* We test `*p == '^' twice, instead of using an if
+			   statement, so we only need one BUF_PUSH.  */
+			BUF_PUSH(*p == '^' ? charset_not : charset);
+			if (*p == '^')
+				p++;
+
+			/* Remember the first position in the bracket expression.  */
+			p1 = p;
+
+			/* Push the number of bytes in the bitmap.  */
+			BUF_PUSH((1 << BYTEWIDTH) / BYTEWIDTH);
+
+			/* Clear the whole map.  */
+			bzero(b, (1 << BYTEWIDTH) / BYTEWIDTH);
+
+			/* charset_not matches newline according to a syntax bit.  */
+			if ((re_opcode_t) b[-2] == charset_not
+				&& (syntax & RE_HAT_LISTS_NOT_NEWLINE)) SET_LIST_BIT('\n');
+
+			/* Read in characters and ranges, setting map bits.  */
+			for (;;) {
+				if (p == pend)
+					FREE_STACK_RETURN(REG_EBRACK);
+
+				PATFETCH(c);
+
+				/* \ might escape characters inside [...] and [^...].  */
+				if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\') {
+					if (p == pend)
+						FREE_STACK_RETURN(REG_EESCAPE);
+
+					PATFETCH(c1);
+					SET_LIST_BIT(c1);
+					continue;
+				}
+
+				/* Could be the end of the bracket expression.  If it's
+				   not (i.e., when the bracket expression is `[]' so
+				   far), the ']' character bit gets set way below.  */
+				if (c == ']' && p != p1 + 1)
+					break;
+
+				/* Look ahead to see if it's a range when the last thing
+				   was a character class.  */
+				if (had_char_class && c == '-' && *p != ']')
+					FREE_STACK_RETURN(REG_ERANGE);
+
+				/* Look ahead to see if it's a range when the last thing
+				   was a character: if this is a hyphen not at the
+				   beginning or the end of a list, then it's the range
+				   operator.  */
+				if (c == '-' && !(p - 2 >= pattern && p[-2] == '[')
+					&& !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
+					&& *p != ']') {
+					reg_errcode_t ret
+						= compile_range(&p, pend, translate, syntax, b);
+
+					if (ret != REG_NOERROR)
+						FREE_STACK_RETURN(ret);
+				}
+
+				else if (p[0] == '-' && p[1] != ']') {	/* This handles ranges made up of characters only.  */
+					reg_errcode_t ret;
+
+					/* Move past the `-'.  */
+					PATFETCH(c1);
+
+					ret = compile_range(&p, pend, translate, syntax, b);
+					if (ret != REG_NOERROR)
+						FREE_STACK_RETURN(ret);
+				}
+
+				/* See if we're at the beginning of a possible character
+				   class.  */
+
+				else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':') {	/* Leave room for the null.  */
+					char str[CHAR_CLASS_MAX_LENGTH + 1];
+
+					PATFETCH(c);
+					c1 = 0;
+
+					/* If pattern is `[[:'.  */
+					if (p == pend)
+						FREE_STACK_RETURN(REG_EBRACK);
+
+					for (;;) {
+						PATFETCH(c);
+						if ((c == ':' && *p == ']') || p == pend)
+							break;
+						if (c1 < CHAR_CLASS_MAX_LENGTH)
+							str[c1++] = c;
+						else
+							/* This is in any case an invalid class name.  */
+							str[0] = '\0';
+					}
+					str[c1] = '\0';
+
+					/* If isn't a word bracketed by `[:' and `:]':
+					   undo the ending character, the letters, and leave
+					   the leading `:' and `[' (but set bits for them).  */
+					if (c == ':' && *p == ']') {
+#if defined _LIBC || WIDE_CHAR_SUPPORT
+						boolean is_lower = STREQ(str, "lower");
+						boolean is_upper = STREQ(str, "upper");
+						wctype_t wt;
+						int ch;
+
+						wt = IS_CHAR_CLASS(str);
+						if (wt == 0)
+							FREE_STACK_RETURN(REG_ECTYPE);
+
+						/* Throw away the ] at the end of the character
+						   class.  */
+						PATFETCH(c);
+
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EBRACK);
+
+						for (ch = 0; ch < 1 << BYTEWIDTH; ++ch) {
+# ifdef _LIBC
+							if (__iswctype(__btowc(ch), wt))
+								SET_LIST_BIT(ch);
+# else
+							if (iswctype(btowc(ch), wt))
+								SET_LIST_BIT(ch);
+# endif
+
+							if (translate && (is_upper || is_lower)
+								&& (ISUPPER(ch) || ISLOWER(ch)))
+								SET_LIST_BIT(ch);
+						}
+
+						had_char_class = true;
+#else
+						int ch;
+						boolean is_alnum = STREQ(str, "alnum");
+						boolean is_alpha = STREQ(str, "alpha");
+						boolean is_blank = STREQ(str, "blank");
+						boolean is_cntrl = STREQ(str, "cntrl");
+						boolean is_digit = STREQ(str, "digit");
+						boolean is_graph = STREQ(str, "graph");
+						boolean is_lower = STREQ(str, "lower");
+						boolean is_print = STREQ(str, "print");
+						boolean is_punct = STREQ(str, "punct");
+						boolean is_space = STREQ(str, "space");
+						boolean is_upper = STREQ(str, "upper");
+						boolean is_xdigit = STREQ(str, "xdigit");
+
+						if (!IS_CHAR_CLASS(str))
+							FREE_STACK_RETURN(REG_ECTYPE);
+
+						/* Throw away the ] at the end of the character
+						   class.  */
+						PATFETCH(c);
+
+						if (p == pend)
+							FREE_STACK_RETURN(REG_EBRACK);
+
+						for (ch = 0; ch < 1 << BYTEWIDTH; ch++) {
+							/* This was split into 3 if's to
+							   avoid an arbitrary limit in some compiler.  */
+							if ((is_alnum && ISALNUM(ch))
+								|| (is_alpha && ISALPHA(ch))
+								|| (is_blank && ISBLANK(ch))
+								|| (is_cntrl && ISCNTRL(ch)))
+								SET_LIST_BIT(ch);
+							if ((is_digit && ISDIGIT(ch))
+								|| (is_graph && ISGRAPH(ch))
+								|| (is_lower && ISLOWER(ch))
+								|| (is_print && ISPRINT(ch)))
+								SET_LIST_BIT(ch);
+							if ((is_punct && ISPUNCT(ch))
+								|| (is_space && ISSPACE(ch))
+								|| (is_upper && ISUPPER(ch))
+								|| (is_xdigit && ISXDIGIT(ch)))
+								SET_LIST_BIT(ch);
+							if (translate && (is_upper || is_lower)
+								&& (ISUPPER(ch) || ISLOWER(ch)))
+								SET_LIST_BIT(ch);
+						}
+						had_char_class = true;
+#endif							/* libc || wctype.h */
+					} else {
+						c1++;
+						while (c1--)
+							PATUNFETCH;
+						SET_LIST_BIT('[');
+						SET_LIST_BIT(':');
+						had_char_class = false;
+					}
+				} else {
+					had_char_class = false;
+					SET_LIST_BIT(c);
+				}
+			}
+
+			/* Discard any (non)matching list bytes that are all 0 at the
+			   end of the map.  Decrease the map-length byte too.  */
+			while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
+				b[-1]--;
+			b += b[-1];
+		}
+			break;
+
+
+		case '(':
+			if (syntax & RE_NO_BK_PARENS)
+				goto handle_open;
+			else
+				goto normal_char;
+
+
+		case ')':
+			if (syntax & RE_NO_BK_PARENS)
+				goto handle_close;
+			else
+				goto normal_char;
+
+
+		case '\n':
+			if (syntax & RE_NEWLINE_ALT)
+				goto handle_alt;
+			else
+				goto normal_char;
+
+
+		case '|':
+			if (syntax & RE_NO_BK_VBAR)
+				goto handle_alt;
+			else
+				goto normal_char;
+
+
+		case '{':
+			if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
+				goto handle_interval;
+			else
+				goto normal_char;
+
+
+		case '\\':
+			if (p == pend)
+				FREE_STACK_RETURN(REG_EESCAPE);
+
+			/* Do not translate the character after the \, so that we can
+			   distinguish, e.g., \B from \b, even if we normally would
+			   translate, e.g., B to b.  */
+			PATFETCH_RAW(c);
+
+			switch (c) {
+			case '(':
+				if (syntax & RE_NO_BK_PARENS)
+					goto normal_backslash;
+
+			  handle_open:
+				bufp->re_nsub++;
+				regnum++;
+
+				if (COMPILE_STACK_FULL) {
+					RETALLOC(compile_stack.stack, compile_stack.size << 1,
+							 compile_stack_elt_t);
+					if (compile_stack.stack == NULL)
+						return REG_ESPACE;
+
+					compile_stack.size <<= 1;
+				}
+
+				/* These are the values to restore when we hit end of this
+				   group.  They are all relative offsets, so that if the
+				   whole pattern moves because of realloc, they will still
+				   be valid.  */
+				COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
+				COMPILE_STACK_TOP.fixup_alt_jump
+					=
+					fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
+				COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
+				COMPILE_STACK_TOP.regnum = regnum;
+
+				/* We will eventually replace the 0 with the number of
+				   groups inner to this one.  But do not push a
+				   start_memory for groups beyond the last one we can
+				   represent in the compiled pattern.  */
+				if (regnum <= MAX_REGNUM) {
+					COMPILE_STACK_TOP.inner_group_offset =
+						b - bufp->buffer + 2;
+					BUF_PUSH_3(start_memory, regnum, 0);
+				}
+
+				compile_stack.avail++;
+
+				fixup_alt_jump = 0;
+				laststart = 0;
+				begalt = b;
+				/* If we've reached MAX_REGNUM groups, then this open
+				   won't actually generate any code, so we'll have to
+				   clear pending_exact explicitly.  */
+				pending_exact = 0;
+				break;
+
+
+			case ')':
+				if (syntax & RE_NO_BK_PARENS)
+					goto normal_backslash;
+
+				if (COMPILE_STACK_EMPTY) {
+					if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
+						goto normal_backslash;
+					else
+						FREE_STACK_RETURN(REG_ERPAREN);
+				}
+
+			  handle_close:
+				if (fixup_alt_jump) {	/* Push a dummy failure point at the end of the
+										   alternative for a possible future
+										   `pop_failure_jump' to pop.  See comments at
+										   `push_dummy_failure' in `re_match_2'.  */
+					BUF_PUSH(push_dummy_failure);
+
+					/* We allocated space for this jump when we assigned
+					   to `fixup_alt_jump', in the `handle_alt' case below.  */
+					STORE_JUMP(jump_past_alt, fixup_alt_jump, b - 1);
+				}
+
+				/* See similar code for backslashed left paren above.  */
+				if (COMPILE_STACK_EMPTY) {
+					if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
+						goto normal_char;
+					else
+						FREE_STACK_RETURN(REG_ERPAREN);
+				}
+
+				/* Since we just checked for an empty stack above, this
+				   ``can't happen''.  */
+				assert(compile_stack.avail != 0);
+				{
+					/* We don't just want to restore into `regnum', because
+					   later groups should continue to be numbered higher,
+					   as in `(ab)c(de)' -- the second group is #2.  */
+					regnum_t this_group_regnum;
+
+					compile_stack.avail--;
+					begalt =
+						bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
+					fixup_alt_jump =
+						COMPILE_STACK_TOP.fixup_alt_jump ? bufp->buffer +
+						COMPILE_STACK_TOP.fixup_alt_jump - 1 : 0;
+					laststart =
+						bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
+					this_group_regnum = COMPILE_STACK_TOP.regnum;
+					/* If we've reached MAX_REGNUM groups, then this open
+					   won't actually generate any code, so we'll have to
+					   clear pending_exact explicitly.  */
+					pending_exact = 0;
+
+					/* We're at the end of the group, so now we know how many
+					   groups were inside this one.  */
+					if (this_group_regnum <= MAX_REGNUM) {
+						unsigned char *inner_group_loc
+
+							=
+							bufp->buffer +
+							COMPILE_STACK_TOP.inner_group_offset;
+
+						*inner_group_loc = regnum - this_group_regnum;
+						BUF_PUSH_3(stop_memory, this_group_regnum,
+								   regnum - this_group_regnum);
+					}
+				}
+				break;
+
+
+			case '|':			/* `\|'.  */
+				if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
+					goto normal_backslash;
+			  handle_alt:
+				if (syntax & RE_LIMITED_OPS)
+					goto normal_char;
+
+				/* Insert before the previous alternative a jump which
+				   jumps to this alternative if the former fails.  */
+				GET_BUFFER_SPACE(3);
+				INSERT_JUMP(on_failure_jump, begalt, b + 6);
+				pending_exact = 0;
+				b += 3;
+
+				/* The alternative before this one has a jump after it
+				   which gets executed if it gets matched.  Adjust that
+				   jump so it will jump to this alternative's analogous
+				   jump (put in below, which in turn will jump to the next
+				   (if any) alternative's such jump, etc.).  The last such
+				   jump jumps to the correct final destination.  A picture:
+				   _____ _____
+				   |   | |   |
+				   |   v |   v
+				   a | b   | c
+
+				   If we are at `b', then fixup_alt_jump right now points to a
+				   three-byte space after `a'.  We'll put in the jump, set
+				   fixup_alt_jump to right after `b', and leave behind three
+				   bytes which we'll fill in when we get to after `c'.  */
+
+				if (fixup_alt_jump)
+					STORE_JUMP(jump_past_alt, fixup_alt_jump, b);
+
+				/* Mark and leave space for a jump after this alternative,
+				   to be filled in later either by next alternative or
+				   when know we're at the end of a series of alternatives.  */
+				fixup_alt_jump = b;
+				GET_BUFFER_SPACE(3);
+				b += 3;
+
+				laststart = 0;
+				begalt = b;
+				break;
+
+
+			case '{':
+				/* If \{ is a literal.  */
+				if (!(syntax & RE_INTERVALS)
+					/* If we're at `\{' and it's not the open-interval
+					   operator.  */
+					|| ((syntax & RE_INTERVALS)
+						&& (syntax & RE_NO_BK_BRACES)) || (p - 2 == pattern
+														   && p == pend))
+					goto normal_backslash;
+
+			  handle_interval:
+				{
+					/* If got here, then the syntax allows intervals.  */
+
+					/* At least (most) this many matches must be made.  */
+					int lower_bound = -1, upper_bound = -1;
+
+					beg_interval = p - 1;
+
+					if (p == pend) {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_EBRACE);
+					}
+
+					GET_UNSIGNED_NUMBER(lower_bound);
+
+					if (c == ',') {
+						GET_UNSIGNED_NUMBER(upper_bound);
+						if ((!(syntax & RE_NO_BK_BRACES) && c != '\\')
+							|| ((syntax & RE_NO_BK_BRACES) && c != '}'))
+							FREE_STACK_RETURN(REG_BADBR);
+
+						if (upper_bound < 0)
+							upper_bound = RE_DUP_MAX;
+					} else
+						/* Interval such as `{1}' => match exactly once. */
+						upper_bound = lower_bound;
+
+					if (lower_bound < 0 || upper_bound > RE_DUP_MAX
+						|| lower_bound > upper_bound) {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_BADBR);
+					}
+
+					if (!(syntax & RE_NO_BK_BRACES)) {
+						if (c != '\\')
+							FREE_STACK_RETURN(REG_EBRACE);
+
+						PATFETCH(c);
+					}
+
+					if (c != '}') {
+						if (!(syntax & RE_INTERVALS)
+							&& (syntax & RE_NO_BK_BRACES)) goto
+								unfetch_interval;
+						else
+							FREE_STACK_RETURN(REG_BADBR);
+					}
+
+					/* We just parsed a valid interval.  */
+
+					/* If it's invalid to have no preceding re.  */
+					if (!laststart) {
+						if (syntax & RE_CONTEXT_INVALID_OPS)
+							FREE_STACK_RETURN(REG_BADRPT);
+						else if (syntax & RE_CONTEXT_INDEP_OPS)
+							laststart = b;
+						else
+							goto unfetch_interval;
+					}
+
+					/* If the upper bound is zero, don't want to succeed at
+					   all; jump from `laststart' to `b + 3', which will be
+					   the end of the buffer after we insert the jump.  */
+					if (upper_bound == 0) {
+						GET_BUFFER_SPACE(3);
+						INSERT_JUMP(jump, laststart, b + 3);
+						b += 3;
+					}
+
+					/* Otherwise, we have a nontrivial interval.  When
+					   we're all done, the pattern will look like:
+					   set_number_at <jump count> <upper bound>
+					   set_number_at <succeed_n count> <lower bound>
+					   succeed_n <after jump addr> <succeed_n count>
+					   <body of loop>
+					   jump_n <succeed_n addr> <jump count>
+					   (The upper bound and `jump_n' are omitted if
+					   `upper_bound' is 1, though.)  */
+					else {		/* If the upper bound is > 1, we need to insert
+								   more at the end of the loop.  */
+						unsigned nbytes = 10 + (upper_bound > 1) * 10;
+
+						GET_BUFFER_SPACE(nbytes);
+
+						/* Initialize lower bound of the `succeed_n', even
+						   though it will be set during matching by its
+						   attendant `set_number_at' (inserted next),
+						   because `re_compile_fastmap' needs to know.
+						   Jump to the `jump_n' we might insert below.  */
+						INSERT_JUMP2(succeed_n, laststart,
+									 b + 5 + (upper_bound > 1) * 5,
+									 lower_bound);
+						b += 5;
+
+						/* Code to initialize the lower bound.  Insert
+						   before the `succeed_n'.  The `5' is the last two
+						   bytes of this `set_number_at', plus 3 bytes of
+						   the following `succeed_n'.  */
+						insert_op2(set_number_at, laststart, 5,
+								   lower_bound, b);
+						b += 5;
+
+						if (upper_bound > 1) {	/* More than one repetition is allowed, so
+												   append a backward jump to the `succeed_n'
+												   that starts this interval.
+
+												   When we've reached this during matching,
+												   we'll have matched the interval once, so
+												   jump back only `upper_bound - 1' times.  */
+							STORE_JUMP2(jump_n, b, laststart + 5,
+										upper_bound - 1);
+							b += 5;
+
+							/* The location we want to set is the second
+							   parameter of the `jump_n'; that is `b-2' as
+							   an absolute address.  `laststart' will be
+							   the `set_number_at' we're about to insert;
+							   `laststart+3' the number to set, the source
+							   for the relative address.  But we are
+							   inserting into the middle of the pattern --
+							   so everything is getting moved up by 5.
+							   Conclusion: (b - 2) - (laststart + 3) + 5,
+							   i.e., b - laststart.
+
+							   We insert this at the beginning of the loop
+							   so that if we fail during matching, we'll
+							   reinitialize the bounds.  */
+							insert_op2(set_number_at, laststart,
+									   b - laststart, upper_bound - 1, b);
+							b += 5;
+						}
+					}
+					pending_exact = 0;
+					beg_interval = NULL;
+				}
+				break;
+
+			  unfetch_interval:
+				/* If an invalid interval, match the characters as literals.  */
+				assert(beg_interval);
+				p = beg_interval;
+				beg_interval = NULL;
+
+				/* normal_char and normal_backslash need `c'.  */
+				PATFETCH(c);
+
+				if (!(syntax & RE_NO_BK_BRACES)) {
+					if (p > pattern && p[-1] == '\\')
+						goto normal_backslash;
+				}
+				goto normal_char;
+
+#ifdef emacs
+				/* There is no way to specify the before_dot and after_dot
+				   operators.  rms says this is ok.  --karl  */
+			case '=':
+				BUF_PUSH(at_dot);
+				break;
+
+			case 's':
+				laststart = b;
+				PATFETCH(c);
+				BUF_PUSH_2(syntaxspec, syntax_spec_code[c]);
+				break;
+
+			case 'S':
+				laststart = b;
+				PATFETCH(c);
+				BUF_PUSH_2(notsyntaxspec, syntax_spec_code[c]);
+				break;
+#endif							/* emacs */
+
+
+			case 'w':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				laststart = b;
+				BUF_PUSH(wordchar);
+				break;
+
+
+			case 'W':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				laststart = b;
+				BUF_PUSH(notwordchar);
+				break;
+
+
+			case '<':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordbeg);
+				break;
+
+			case '>':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordend);
+				break;
+
+			case 'b':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(wordbound);
+				break;
+
+			case 'B':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(notwordbound);
+				break;
+
+			case '`':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(begbuf);
+				break;
+
+			case '\'':
+				if (syntax & RE_NO_GNU_OPS)
+					goto normal_char;
+				BUF_PUSH(endbuf);
+				break;
+
+			case '1':
+			case '2':
+			case '3':
+			case '4':
+			case '5':
+			case '6':
+			case '7':
+			case '8':
+			case '9':
+				if (syntax & RE_NO_BK_REFS)
+					goto normal_char;
+
+				c1 = c - '0';
+
+				if (c1 > regnum)
+					FREE_STACK_RETURN(REG_ESUBREG);
+
+				/* Can't back reference to a subexpression if inside of it.  */
+				if (group_in_compile_stack(compile_stack, (regnum_t) c1))
+					goto normal_char;
+
+				laststart = b;
+				BUF_PUSH_2(duplicate, c1);
+				break;
+
+
+			case '+':
+			case '?':
+				if (syntax & RE_BK_PLUS_QM)
+					goto handle_plus;
+				else
+					goto normal_backslash;
+
+			default:
+			  normal_backslash:
+				/* You might think it would be useful for \ to mean
+				   not to translate; but if we don't translate it
+				   it will never match anything.  */
+				c = TRANSLATE(c);
+				goto normal_char;
+			}
+			break;
+
+
+		default:
+			/* Expects the character in `c'.  */
+		  normal_char:
+			/* If no exactn currently being built.  */
+			if (!pending_exact
+				/* If last exactn not at current position.  */
+				|| pending_exact + *pending_exact + 1 != b
+				/* We have only one byte following the exactn for the count.  */
+				|| *pending_exact == (1 << BYTEWIDTH) - 1
+				/* If followed by a repetition operator.  */
+				|| *p == '*' || *p == '^' || ((syntax & RE_BK_PLUS_QM)
+											  ? *p == '\\' && (p[1] == '+'
+															   || p[1] ==
+															   '?') : (*p
+																	   ==
+																	   '+'
+																	   ||
+																	   *p
+																	   ==
+																	   '?'))
+				|| ((syntax & RE_INTERVALS)
+					&& ((syntax & RE_NO_BK_BRACES)
+						? *p == '{' : (p[0] == '\\' && p[1] == '{')))) {
+				/* Start building a new exactn.  */
+
+				laststart = b;
+
+				BUF_PUSH_2(exactn, 0);
+				pending_exact = b - 1;
+			}
+
+			BUF_PUSH(c);
+			(*pending_exact)++;
+			break;
+		}						/* switch (c) */
+	}							/* while p != pend */
+
+
+	/* Through the pattern now.  */
+
+	if (fixup_alt_jump)
+		STORE_JUMP(jump_past_alt, fixup_alt_jump, b);
+
+	if (!COMPILE_STACK_EMPTY)
+		FREE_STACK_RETURN(REG_EPAREN);
+
+	/* If we don't want backtracking, force success
+	   the first time we reach the end of the compiled pattern.  */
+	if (syntax & RE_NO_POSIX_BACKTRACKING)
+		BUF_PUSH(succeed);
+
+	free(compile_stack.stack);
+
+	/* We have succeeded; set the length of the buffer.  */
+	bufp->used = b - bufp->buffer;
+
+#ifdef DEBUG
+	if (debug) {
+		DEBUG_PRINT1("\nCompiled pattern: \n");
+		print_compiled_pattern(bufp);
+	}
+#endif							/* DEBUG */
+
+#ifndef MATCH_MAY_ALLOCATE
+	/* Initialize the failure stack to the largest possible stack.  This
+	   isn't necessary unless we're trying to avoid calling alloca in
+	   the search and match routines.  */
+	{
+		int num_regs = bufp->re_nsub + 1;
+
+		/* Since DOUBLE_FAIL_STACK refuses to double only if the current size
+		   is strictly greater than re_max_failures, the largest possible stack
+		   is 2 * re_max_failures failure points.  */
+		if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS)) {
+			fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
+
+# ifdef emacs
+			if (!fail_stack.stack)
+				fail_stack.stack
+					= (fail_stack_elt_t *) xmalloc(fail_stack.size
+												   *
+												   sizeof
+												   (fail_stack_elt_t));
+			else
+				fail_stack.stack =
+					(fail_stack_elt_t *) xrealloc(fail_stack.stack,
+												  (fail_stack.size *
+												   sizeof
+												   (fail_stack_elt_t)));
+# else							/* not emacs */
+			if (!fail_stack.stack)
+				fail_stack.stack
+					= (fail_stack_elt_t *) malloc(fail_stack.size
+												  *
+												  sizeof
+												  (fail_stack_elt_t));
+			else
+				fail_stack.stack =
+					(fail_stack_elt_t *) realloc(fail_stack.stack,
+												 (fail_stack.size *
+												  sizeof
+												  (fail_stack_elt_t)));
+# endif							/* not emacs */
+		}
+
+		regex_grow_registers(num_regs);
+	}
+#endif							/* not MATCH_MAY_ALLOCATE */
+
+	return REG_NOERROR;
+}								/* regex_compile */
+
+/* Subroutines for `regex_compile'.  */
+
+/* Store OP at LOC followed by two-byte integer parameter ARG.  */
+
+static void store_op1(op, loc, arg)
+re_opcode_t op;
+unsigned char *loc;
+int arg;
+{
+	*loc = (unsigned char) op;
+	STORE_NUMBER(loc + 1, arg);
+}
+
+
+/* Like `store_op1', but for two two-byte parameters ARG1 and ARG2.  */
+
+static void store_op2(op, loc, arg1, arg2)
+re_opcode_t op;
+unsigned char *loc;
+int arg1, arg2;
+{
+	*loc = (unsigned char) op;
+	STORE_NUMBER(loc + 1, arg1);
+	STORE_NUMBER(loc + 3, arg2);
+}
+
+
+/* Copy the bytes from LOC to END to open up three bytes of space at LOC
+   for OP followed by two-byte integer parameter ARG.  */
+
+static void insert_op1(op, loc, arg, end)
+re_opcode_t op;
+unsigned char *loc;
+int arg;
+unsigned char *end;
+{
+	register unsigned char *pfrom = end;
+	register unsigned char *pto = end + 3;
+
+	while (pfrom != loc)
+		*--pto = *--pfrom;
+
+	store_op1(op, loc, arg);
+}
+
+
+/* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2.  */
+
+static void insert_op2(op, loc, arg1, arg2, end)
+re_opcode_t op;
+unsigned char *loc;
+int arg1, arg2;
+unsigned char *end;
+{
+	register unsigned char *pfrom = end;
+	register unsigned char *pto = end + 5;
+
+	while (pfrom != loc)
+		*--pto = *--pfrom;
+
+	store_op2(op, loc, arg1, arg2);
+}
+
+
+/* P points to just after a ^ in PATTERN.  Return true if that ^ comes
+   after an alternative or a begin-subexpression.  We assume there is at
+   least one character before the ^.  */
+
+static boolean at_begline_loc_p(pattern, p, syntax)
+const char *pattern, *p;
+reg_syntax_t syntax;
+{
+	const char *prev = p - 2;
+	boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
+
+	return
+		/* After a subexpression?  */
+		(*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
+		/* After an alternative?  */
+		|| (*prev == '|'
+			&& (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
+}
+
+
+/* The dual of at_begline_loc_p.  This one is for $.  We assume there is
+   at least one character after the $, i.e., `P < PEND'.  */
+
+static boolean at_endline_loc_p(p, pend, syntax)
+const char *p, *pend;
+reg_syntax_t syntax;
+{
+	const char *next = p;
+	boolean next_backslash = *next == '\\';
+	const char *next_next = p + 1 < pend ? p + 1 : 0;
+
+	return
+		/* Before a subexpression?  */
+		(syntax & RE_NO_BK_PARENS ? *next == ')'
+		 : next_backslash && next_next && *next_next == ')')
+		/* Before an alternative?  */
+		|| (syntax & RE_NO_BK_VBAR ? *next == '|'
+			: next_backslash && next_next && *next_next == '|');
+}
+
+
+/* Returns true if REGNUM is in one of COMPILE_STACK's elements and
+   false if it's not.  */
+
+static boolean group_in_compile_stack(compile_stack, regnum)
+compile_stack_type compile_stack;
+regnum_t regnum;
+{
+	int this_element;
+
+	for (this_element = compile_stack.avail - 1;
+		 this_element >= 0; this_element--)
+		if (compile_stack.stack[this_element].regnum == regnum)
+			return true;
+
+	return false;
+}
+
+
+/* Read the ending character of a range (in a bracket expression) from the
+   uncompiled pattern *P_PTR (which ends at PEND).  We assume the
+   starting character is in `P[-2]'.  (`P[-1]' is the character `-'.)
+   Then we set the translation of all bits between the starting and
+   ending characters (inclusive) in the compiled pattern B.
+
+   Return an error code.
+
+   We use these short variable names so we can use the same macros as
+   `regex_compile' itself.  */
+
+static reg_errcode_t compile_range(p_ptr, pend, translate, syntax, b)
+const char **p_ptr, *pend;
+RE_TRANSLATE_TYPE translate;
+reg_syntax_t syntax;
+unsigned char *b;
+{
+	unsigned this_char;
+
+	const char *p = *p_ptr;
+	reg_errcode_t ret;
+	char range_start[2];
+	char range_end[2];
+	char ch[2];
+
+	if (p == pend)
+		return REG_ERANGE;
+
+	/* Fetch the endpoints without translating them; the
+	   appropriate translation is done in the bit-setting loop below.  */
+	range_start[0] = p[-2];
+	range_start[1] = '\0';
+	range_end[0] = p[0];
+	range_end[1] = '\0';
+
+	/* Have to increment the pointer into the pattern string, so the
+	   caller isn't still at the ending character.  */
+	(*p_ptr)++;
+
+	/* Report an error if the range is empty and the syntax prohibits this.  */
+	ret = syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
+
+	/* Here we see why `this_char' has to be larger than an `unsigned
+	   char' -- we would otherwise go into an infinite loop, since all
+	   characters <= 0xff.  */
+	ch[1] = '\0';
+	for (this_char = 0; this_char <= (unsigned char) -1; ++this_char) {
+		ch[0] = this_char;
+		if (strcoll(range_start, ch) <= 0 && strcoll(ch, range_end) <= 0) {
+			SET_LIST_BIT(TRANSLATE(this_char));
+			ret = REG_NOERROR;
+		}
+	}
+
+	return ret;
+}
+
+/* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
+   BUFP.  A fastmap records which of the (1 << BYTEWIDTH) possible
+   characters can start a string that matches the pattern.  This fastmap
+   is used by re_search to skip quickly over impossible starting points.
+
+   The caller must supply the address of a (1 << BYTEWIDTH)-byte data
+   area as BUFP->fastmap.
+
+   We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
+   the pattern buffer.
+
+   Returns 0 if we succeed, -2 if an internal error.   */
+
+int re_compile_fastmap(bufp)
+struct re_pattern_buffer *bufp;
+{
+	int j, k;
+
+#ifdef MATCH_MAY_ALLOCATE
+	fail_stack_type fail_stack;
+#endif
+#ifndef REGEX_MALLOC
+	char *destination;
+#endif
+
+	register char *fastmap = bufp->fastmap;
+	unsigned char *pattern = bufp->buffer;
+	unsigned char *p = pattern;
+	register unsigned char *pend = pattern + bufp->used;
+
+#ifdef REL_ALLOC
+	/* This holds the pointer to the failure stack, when
+	   it is allocated relocatably.  */
+	fail_stack_elt_t *failure_stack_ptr;
+#endif
+
+	/* Assume that each path through the pattern can be null until
+	   proven otherwise.  We set this false at the bottom of switch
+	   statement, to which we get only if a particular path doesn't
+	   match the empty string.  */
+	boolean path_can_be_null = true;
+
+	/* We aren't doing a `succeed_n' to begin with.  */
+	boolean succeed_n_p = false;
+
+	assert(fastmap != NULL && p != NULL);
+
+	INIT_FAIL_STACK();
+	bzero(fastmap, 1 << BYTEWIDTH);	/* Assume nothing's valid.  */
+	bufp->fastmap_accurate = 1;	/* It will be when we're done.  */
+	bufp->can_be_null = 0;
+
+	while (1) {
+		if (p == pend || *p == succeed) {
+			/* We have reached the (effective) end of pattern.  */
+			if (!FAIL_STACK_EMPTY()) {
+				bufp->can_be_null |= path_can_be_null;
+
+				/* Reset for next path.  */
+				path_can_be_null = true;
+
+				p = fail_stack.stack[--fail_stack.avail].pointer;
+
+				continue;
+			} else
+				break;
+		}
+
+		/* We should never be about to go beyond the end of the pattern.  */
+		assert(p < pend);
+
+		switch (SWITCH_ENUM_CAST((re_opcode_t) * p++)) {
+
+			/* I guess the idea here is to simply not bother with a fastmap
+			   if a backreference is used, since it's too hard to figure out
+			   the fastmap for the corresponding group.  Setting
+			   `can_be_null' stops `re_search_2' from using the fastmap, so
+			   that is all we do.  */
+		case duplicate:
+			bufp->can_be_null = 1;
+			goto done;
+
+
+			/* Following are the cases which match a character.  These end
+			   with `break'.  */
+
+		case exactn:
+			fastmap[p[1]] = 1;
+			break;
+
+
+		case charset:
+			for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
+				if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
+					fastmap[j] = 1;
+			break;
+
+
+		case charset_not:
+			/* Chars beyond end of map must be allowed.  */
+			for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
+				fastmap[j] = 1;
+
+			for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
+				if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
+					fastmap[j] = 1;
+			break;
+
+
+		case wordchar:
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) == Sword)
+					fastmap[j] = 1;
+			break;
+
+
+		case notwordchar:
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) != Sword)
+					fastmap[j] = 1;
+			break;
+
+
+		case anychar:
+		{
+			int fastmap_newline = fastmap['\n'];
+
+			/* `.' matches anything ...  */
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				fastmap[j] = 1;
+
+			/* ... except perhaps newline.  */
+			if (!(bufp->syntax & RE_DOT_NEWLINE))
+				fastmap['\n'] = fastmap_newline;
+
+			/* Return if we have already set `can_be_null'; if we have,
+			   then the fastmap is irrelevant.  Something's wrong here.  */
+			else if (bufp->can_be_null)
+				goto done;
+
+			/* Otherwise, have to check alternative paths.  */
+			break;
+		}
+
+#ifdef emacs
+		case syntaxspec:
+			k = *p++;
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) == (enum syntaxcode) k)
+					fastmap[j] = 1;
+			break;
+
+
+		case notsyntaxspec:
+			k = *p++;
+			for (j = 0; j < (1 << BYTEWIDTH); j++)
+				if (SYNTAX(j) != (enum syntaxcode) k)
+					fastmap[j] = 1;
+			break;
+
+
+			/* All cases after this match the empty string.  These end with
+			   `continue'.  */
+
+
+		case before_dot:
+		case at_dot:
+		case after_dot:
+			continue;
+#endif							/* emacs */
+
+
+		case no_op:
+		case begline:
+		case endline:
+		case begbuf:
+		case endbuf:
+		case wordbound:
+		case notwordbound:
+		case wordbeg:
+		case wordend:
+		case push_dummy_failure:
+			continue;
+
+
+		case jump_n:
+		case pop_failure_jump:
+		case maybe_pop_jump:
+		case jump:
+		case jump_past_alt:
+		case dummy_failure_jump:
+			EXTRACT_NUMBER_AND_INCR(j, p);
+			p += j;
+			if (j > 0)
+				continue;
+
+			/* Jump backward implies we just went through the body of a
+			   loop and matched nothing.  Opcode jumped to should be
+			   `on_failure_jump' or `succeed_n'.  Just treat it like an
+			   ordinary jump.  For a * loop, it has pushed its failure
+			   point already; if so, discard that as redundant.  */
+			if ((re_opcode_t) * p != on_failure_jump
+				&& (re_opcode_t) * p != succeed_n)
+				continue;
+
+			p++;
+			EXTRACT_NUMBER_AND_INCR(j, p);
+			p += j;
+
+			/* If what's on the stack is where we are now, pop it.  */
+			if (!FAIL_STACK_EMPTY()
+				&& fail_stack.stack[fail_stack.avail - 1].pointer == p)
+				fail_stack.avail--;
+
+			continue;
+
+
+		case on_failure_jump:
+		case on_failure_keep_string_jump:
+		  handle_on_failure_jump:
+			EXTRACT_NUMBER_AND_INCR(j, p);
+
+			/* For some patterns, e.g., `(a?)?', `p+j' here points to the
+			   end of the pattern.  We don't want to push such a point,
+			   since when we restore it above, entering the switch will
+			   increment `p' past the end of the pattern.  We don't need
+			   to push such a point since we obviously won't find any more
+			   fastmap entries beyond `pend'.  Such a pattern can match
+			   the null string, though.  */
+			if (p + j < pend) {
+				if (!PUSH_PATTERN_OP(p + j, fail_stack)) {
+					RESET_FAIL_STACK();
+					return -2;
+				}
+			} else
+				bufp->can_be_null = 1;
+
+			if (succeed_n_p) {
+				EXTRACT_NUMBER_AND_INCR(k, p);	/* Skip the n.  */
+				succeed_n_p = false;
+			}
+
+			continue;
+
+
+		case succeed_n:
+			/* Get to the number of times to succeed.  */
+			p += 2;
+
+			/* Increment p past the n for when k != 0.  */
+			EXTRACT_NUMBER_AND_INCR(k, p);
+			if (k == 0) {
+				p -= 4;
+				succeed_n_p = true;	/* Spaghetti code alert.  */
+				goto handle_on_failure_jump;
+			}
+			continue;
+
+
+		case set_number_at:
+			p += 4;
+			continue;
+
+
+		case start_memory:
+		case stop_memory:
+			p += 2;
+			continue;
+
+
+		default:
+			abort();			/* We have listed all the cases.  */
+		}						/* switch *p++ */
+
+		/* Getting here means we have found the possible starting
+		   characters for one path of the pattern -- and that the empty
+		   string does not match.  We need not follow this path further.
+		   Instead, look at the next alternative (remembered on the
+		   stack), or quit if no more.  The test at the top of the loop
+		   does these things.  */
+		path_can_be_null = false;
+		p = pend;
+	}							/* while p */
+
+	/* Set `can_be_null' for the last path (also the first path, if the
+	   pattern is empty).  */
+	bufp->can_be_null |= path_can_be_null;
+
+  done:
+	RESET_FAIL_STACK();
+	return 0;
+}								/* re_compile_fastmap */
+
+#ifdef _LIBC
+weak_alias(__re_compile_fastmap, re_compile_fastmap)
+#endif
+/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
+   ENDS.  Subsequent matches using PATTERN_BUFFER and REGS will use
+   this memory for recording register information.  STARTS and ENDS
+   must be allocated using the malloc library routine, and must each
+   be at least NUM_REGS * sizeof (regoff_t) bytes long.
+
+   If NUM_REGS == 0, then subsequent matches should allocate their own
+   register data.
+
+   Unless this function is called, the first search or match using
+   PATTERN_BUFFER will allocate its own register data, without
+   freeing the old data.  */
+void re_set_registers(bufp, regs, num_regs, starts, ends)
+struct re_pattern_buffer *bufp;
+struct re_registers *regs;
+unsigned num_regs;
+regoff_t *starts, *ends;
+{
+	if (num_regs) {
+		bufp->regs_allocated = REGS_REALLOCATE;
+		regs->num_regs = num_regs;
+		regs->start = starts;
+		regs->end = ends;
+	} else {
+		bufp->regs_allocated = REGS_UNALLOCATED;
+		regs->num_regs = 0;
+		regs->start = regs->end = (regoff_t *) 0;
+	}
+}
+
+#ifdef _LIBC
+weak_alias(__re_set_registers, re_set_registers)
+#endif
+/* Searching routines.  */
+/* Like re_search_2, below, but only one string is specified, and
+   doesn't let you say where to stop matching. */
+int re_search(bufp, string, size, startpos, range, regs)
+struct re_pattern_buffer *bufp;
+const char *string;
+int size, startpos, range;
+struct re_registers *regs;
+{
+	return re_search_2(bufp, NULL, 0, string, size, startpos, range,
+					   regs, size);
+}
+
+#ifdef _LIBC
+weak_alias(__re_search, re_search)
+#endif
+/* Using the compiled pattern in BUFP->buffer, first tries to match the
+   virtual concatenation of STRING1 and STRING2, starting first at index
+   STARTPOS, then at STARTPOS + 1, and so on.
+
+   STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
+
+   RANGE is how far to scan while trying to match.  RANGE = 0 means try
+   only at STARTPOS; in general, the last start tried is STARTPOS +
+   RANGE.
+
+   In REGS, return the indices of the virtual concatenation of STRING1
+   and STRING2 that matched the entire BUFP->buffer and its contained
+   subexpressions.
+
+   Do not consider matching one past the index STOP in the virtual
+   concatenation of STRING1 and STRING2.
+
+   We return either the position in the strings at which the match was
+   found, -1 if no match, or -2 if error (such as failure
+   stack overflow).  */
+int
+re_search_2(bufp, string1, size1, string2, size2, startpos, range, regs,
+			stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int startpos;
+int range;
+struct re_registers *regs;
+int stop;
+{
+	int val;
+	register char *fastmap = bufp->fastmap;
+	register RE_TRANSLATE_TYPE translate = bufp->translate;
+	int total_size = size1 + size2;
+	int endpos = startpos + range;
+
+	/* Check for out-of-range STARTPOS.  */
+	if (startpos < 0 || startpos > total_size)
+		return -1;
+
+	/* Fix up RANGE if it might eventually take us outside
+	   the virtual concatenation of STRING1 and STRING2.
+	   Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE.  */
+	if (endpos < 0)
+		range = 0 - startpos;
+	else if (endpos > total_size)
+		range = total_size - startpos;
+
+	/* If the search isn't to be a backwards one, don't waste time in a
+	   search for a pattern that must be anchored.  */
+	if (bufp->used > 0 && range > 0
+		&& ((re_opcode_t) bufp->buffer[0] == begbuf
+			/* `begline' is like `begbuf' if it cannot match at newlines.  */
+			|| ((re_opcode_t) bufp->buffer[0] == begline
+				&& !bufp->newline_anchor))) {
+		if (startpos > 0)
+			return -1;
+		else
+			range = 1;
+	}
+#ifdef emacs
+	/* In a forward search for something that starts with \=.
+	   don't keep searching past point.  */
+	if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot
+		&& range > 0) {
+		range = PT - startpos;
+		if (range <= 0)
+			return -1;
+	}
+#endif							/* emacs */
+
+	/* Update the fastmap now if not correct already.  */
+	if (fastmap && !bufp->fastmap_accurate)
+		if (re_compile_fastmap(bufp) == -2)
+			return -2;
+
+	/* Loop through the string, looking for a place to start matching.  */
+	for (;;) {
+		/* If a fastmap is supplied, skip quickly over characters that
+		   cannot be the start of a match.  If the pattern can match the
+		   null string, however, we don't need to skip characters; we want
+		   the first null string.  */
+		if (fastmap && startpos < total_size && !bufp->can_be_null) {
+			if (range > 0) {	/* Searching forwards.  */
+				register const char *d;
+				register int lim = 0;
+				int irange = range;
+
+				if (startpos < size1 && startpos + range >= size1)
+					lim = range - (size1 - startpos);
+
+				d =
+					(startpos >=
+					 size1 ? string2 - size1 : string1) + startpos;
+
+				/* Written out as an if-else to avoid testing `translate'
+				   inside the loop.  */
+				if (translate)
+					while (range > lim && !fastmap[(unsigned char)
+												   translate[
+															 (unsigned
+															  char) *d++]])
+						range--;
+				else
+					while (range > lim && !fastmap[(unsigned char) *d++])
+						range--;
+
+				startpos += irange - range;
+			} else {			/* Searching backwards.  */
+
+				register char c = (size1 == 0 || startpos >= size1
+								   ? string2[startpos - size1]
+								   : string1[startpos]);
+
+				if (!fastmap[(unsigned char) TRANSLATE(c)])
+					goto advance;
+			}
+		}
+
+		/* If can't match the null string, and that's all we have left, fail.  */
+		if (range >= 0 && startpos == total_size && fastmap
+			&& !bufp->can_be_null) return -1;
+
+		val = re_match_2_internal(bufp, string1, size1, string2, size2,
+								  startpos, regs, stop);
+#ifndef REGEX_MALLOC
+# ifdef C_ALLOCA
+		alloca(0);
+# endif
+#endif
+
+		if (val >= 0)
+			return startpos;
+
+		if (val == -2)
+			return -2;
+
+	  advance:
+		if (!range)
+			break;
+		else if (range > 0) {
+			range--;
+			startpos++;
+		} else {
+			range++;
+			startpos--;
+		}
+	}
+	return -1;
+}								/* re_search_2 */
+
+#ifdef _LIBC
+weak_alias(__re_search_2, re_search_2)
+#endif
+/* This converts PTR, a pointer into one of the search strings `string1'
+   and `string2' into an offset from the beginning of that string.  */
+#define POINTER_TO_OFFSET(ptr)			\
+  (FIRST_STRING_P (ptr)				\
+   ? ((regoff_t) ((ptr) - string1))		\
+   : ((regoff_t) ((ptr) - string2 + size1)))
+/* Macros for dealing with the split strings in re_match_2.  */
+#define MATCHING_IN_FIRST_STRING  (dend == end_match_1)
+/* Call before fetching a character with *d.  This switches over to
+   string2 if necessary.  */
+#define PREFETCH()							\
+  while (d == dend)						    	\
+    {									\
+      /* End of string2 => fail.  */					\
+      if (dend == end_match_2) 						\
+        goto fail;							\
+      /* End of string1 => advance to string2.  */ 			\
+      d = string2;						        \
+      dend = end_match_2;						\
+    }
+/* Test if at very beginning or at very end of the virtual concatenation
+   of `string1' and `string2'.  If only one string, it's `string2'.  */
+#define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
+#define AT_STRINGS_END(d) ((d) == end2)
+/* Test if D points to a character which is word-constituent.  We have
+   two special cases to check for: if past the end of string1, look at
+   the first character in string2; and if before the beginning of
+   string2, look at the last character in string1.  */
+#define WORDCHAR_P(d)							\
+  (SYNTAX ((d) == end1 ? *string2					\
+           : (d) == string2 - 1 ? *(end1 - 1) : *(d))			\
+   == Sword)
+/* Disabled due to a compiler bug -- see comment at case wordbound */
+#if 0
+/* Test if the character before D and the one at D differ with respect
+   to being word-constituent.  */
+#define AT_WORD_BOUNDARY(d)						\
+  (AT_STRINGS_BEG (d) || AT_STRINGS_END (d)				\
+   || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
+#endif
+/* Free everything we malloc.  */
+#ifdef MATCH_MAY_ALLOCATE
+# define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
+# define FREE_VARIABLES()						\
+  do {									\
+    REGEX_FREE_STACK (fail_stack.stack);				\
+    FREE_VAR (regstart);						\
+    FREE_VAR (regend);							\
+    FREE_VAR (old_regstart);						\
+    FREE_VAR (old_regend);						\
+    FREE_VAR (best_regstart);						\
+    FREE_VAR (best_regend);						\
+    FREE_VAR (reg_info);						\
+    FREE_VAR (reg_dummy);						\
+    FREE_VAR (reg_info_dummy);						\
+  } while (0)
+#else
+# define FREE_VARIABLES() ((void)0)	/* Do nothing!  But inhibit gcc warning. */
+#endif							/* not MATCH_MAY_ALLOCATE */
+/* These values must meet several constraints.  They must not be valid
+   register values; since we have a limit of 255 registers (because
+   we use only one byte in the pattern for the register number), we can
+   use numbers larger than 255.  They must differ by 1, because of
+   NUM_FAILURE_ITEMS above.  And the value for the lowest register must
+   be larger than the value for the highest register, so we do not try
+   to actually save any registers when none are active.  */
+#define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
+#define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
+/* Matching routines.  */
+#ifndef emacs					/* Emacs never uses this.  */
+/* re_match is like re_match_2 except it takes only a single string.  */
+int re_match(bufp, string, size, pos, regs)
+struct re_pattern_buffer *bufp;
+const char *string;
+int size, pos;
+struct re_registers *regs;
+{
+	int result = re_match_2_internal(bufp, NULL, 0, string, size,
+									 pos, regs, size);
+
+# ifndef REGEX_MALLOC
+#  ifdef C_ALLOCA
+	alloca(0);
+#  endif
+# endif
+	return result;
+}
+
+# ifdef _LIBC
+weak_alias(__re_match, re_match)
+# endif
+#endif							/* not emacs */
+static boolean group_match_null_string_p _RE_ARGS((unsigned char **p,
+												   unsigned char *end,
+												   register_info_type *
+
+												   reg_info));
+static boolean alt_match_null_string_p
+_RE_ARGS(
+
+		 (unsigned char *p, unsigned char *end,
+		  register_info_type * reg_info));
+static boolean common_op_match_null_string_p
+_RE_ARGS(
+
+		 (unsigned char **p, unsigned char *end,
+		  register_info_type * reg_info));
+static int bcmp_translate
+_RE_ARGS((const char *s1, const char *s2, int len, char *translate));
+
+/* re_match_2 matches the compiled pattern in BUFP against the
+   the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
+   and SIZE2, respectively).  We start matching at POS, and stop
+   matching at STOP.
+
+   If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
+   store offsets for the substring each group matched in REGS.  See the
+   documentation for exactly how many groups we fill.
+
+   We return -1 if no match, -2 if an internal error (such as the
+   failure stack overflowing).  Otherwise, we return the length of the
+   matched substring.  */
+
+int re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int pos;
+struct re_registers *regs;
+int stop;
+{
+	int result = re_match_2_internal(bufp, string1, size1, string2, size2,
+									 pos, regs, stop);
+
+#ifndef REGEX_MALLOC
+# ifdef C_ALLOCA
+	alloca(0);
+# endif
+#endif
+	return result;
+}
+
+#ifdef _LIBC
+weak_alias(__re_match_2, re_match_2)
+#endif
+/* This is a separate function so that we can force an alloca cleanup
+   afterwards.  */
+static int
+re_match_2_internal(bufp, string1, size1, string2, size2, pos, regs, stop)
+struct re_pattern_buffer *bufp;
+const char *string1, *string2;
+int size1, size2;
+int pos;
+struct re_registers *regs;
+int stop;
+{
+	/* General temporaries.  */
+	int mcnt;
+	unsigned char *p1;
+
+	/* Just past the end of the corresponding string.  */
+	const char *end1, *end2;
+
+	/* Pointers into string1 and string2, just past the last characters in
+	   each to consider matching.  */
+	const char *end_match_1, *end_match_2;
+
+	/* Where we are in the data, and the end of the current string.  */
+	const char *d, *dend;
+
+	/* Where we are in the pattern, and the end of the pattern.  */
+	unsigned char *p = bufp->buffer;
+	register unsigned char *pend = p + bufp->used;
+
+	/* Mark the opcode just after a start_memory, so we can test for an
+	   empty subpattern when we get to the stop_memory.  */
+	unsigned char *just_past_start_mem = 0;
+
+	/* We use this to map every character in the string.  */
+	RE_TRANSLATE_TYPE translate = bufp->translate;
+
+	/* Failure point stack.  Each place that can handle a failure further
+	   down the line pushes a failure point on this stack.  It consists of
+	   restart, regend, and reg_info for all registers corresponding to
+	   the subexpressions we're currently inside, plus the number of such
+	   registers, and, finally, two char *'s.  The first char * is where
+	   to resume scanning the pattern; the second one is where to resume
+	   scanning the strings.  If the latter is zero, the failure point is
+	   a ``dummy''; if a failure happens and the failure point is a dummy,
+	   it gets discarded and the next next one is tried.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, this is global.  */
+	fail_stack_type fail_stack;
+#endif
+#ifdef DEBUG
+	static unsigned failure_id;
+	unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
+#endif
+
+#ifdef REL_ALLOC
+	/* This holds the pointer to the failure stack, when
+	   it is allocated relocatably.  */
+	fail_stack_elt_t *failure_stack_ptr;
+#endif
+
+	/* We fill all the registers internally, independent of what we
+	   return, for use in backreferences.  The number here includes
+	   an element for register zero.  */
+	size_t num_regs = bufp->re_nsub + 1;
+
+	/* The currently active registers.  */
+	active_reg_t lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+	active_reg_t highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+
+	/* Information on the contents of registers. These are pointers into
+	   the input strings; they record just what was matched (on this
+	   attempt) by a subexpression part of the pattern, that is, the
+	   regnum-th regstart pointer points to where in the pattern we began
+	   matching and the regnum-th regend points to right after where we
+	   stopped matching the regnum-th subexpression.  (The zeroth register
+	   keeps track of what the whole pattern matches.)  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **regstart, **regend;
+#endif
+
+	/* If a group that's operated upon by a repetition operator fails to
+	   match anything, then the register for its start will need to be
+	   restored because it will have been set to wherever in the string we
+	   are when we last see its open-group operator.  Similarly for a
+	   register's end.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **old_regstart, **old_regend;
+#endif
+
+	/* The is_active field of reg_info helps us keep track of which (possibly
+	   nested) subexpressions we are currently in. The matched_something
+	   field of reg_info[reg_num] helps us tell whether or not we have
+	   matched any of the pattern so far this time through the reg_num-th
+	   subexpression.  These two fields get reset each time through any
+	   loop their register is in.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, this is global.  */
+	register_info_type *reg_info;
+#endif
+
+	/* The following record the register info as found in the above
+	   variables when we find a match better than any we've seen before.
+	   This happens as we backtrack through the failure points, which in
+	   turn happens only if we have not yet matched the entire string. */
+	unsigned best_regs_set = false;
+
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **best_regstart, **best_regend;
+#endif
+
+	/* Logically, this is `best_regend[0]'.  But we don't want to have to
+	   allocate space for that if we're not allocating space for anything
+	   else (see below).  Also, we never need info about register 0 for
+	   any of the other register vectors, and it seems rather a kludge to
+	   treat `best_regend' differently than the rest.  So we keep track of
+	   the end of the best match so far in a separate variable.  We
+	   initialize this to NULL so that when we backtrack the first time
+	   and need to test it, it's not garbage.  */
+	const char *match_end = NULL;
+
+	/* This helps SET_REGS_MATCHED avoid doing redundant work.  */
+	int set_regs_matched_done = 0;
+
+	/* Used when we pop values we don't care about.  */
+#ifdef MATCH_MAY_ALLOCATE		/* otherwise, these are global.  */
+	const char **reg_dummy;
+	register_info_type *reg_info_dummy;
+#endif
+
+#ifdef DEBUG
+	/* Counts the total number of registers pushed.  */
+	unsigned num_regs_pushed = 0;
+#endif
+
+	DEBUG_PRINT1("\n\nEntering re_match_2.\n");
+
+	INIT_FAIL_STACK();
+
+#ifdef MATCH_MAY_ALLOCATE
+	/* Do not bother to initialize all the register variables if there are
+	   no groups in the pattern, as it takes a fair amount of time.  If
+	   there are groups, we include space for register 0 (the whole
+	   pattern), even though we never use it, since it simplifies the
+	   array indexing.  We should fix this.  */
+	if (bufp->re_nsub) {
+		regstart = REGEX_TALLOC(num_regs, const char *);
+		regend = REGEX_TALLOC(num_regs, const char *);
+		old_regstart = REGEX_TALLOC(num_regs, const char *);
+		old_regend = REGEX_TALLOC(num_regs, const char *);
+		best_regstart = REGEX_TALLOC(num_regs, const char *);
+		best_regend = REGEX_TALLOC(num_regs, const char *);
+
+		reg_info = REGEX_TALLOC(num_regs, register_info_type);
+		reg_dummy = REGEX_TALLOC(num_regs, const char *);
+
+		reg_info_dummy = REGEX_TALLOC(num_regs, register_info_type);
+
+		if (!(regstart && regend && old_regstart && old_regend && reg_info
+			  && best_regstart && best_regend && reg_dummy
+			  && reg_info_dummy)) {
+			FREE_VARIABLES();
+			return -2;
+		}
+	} else {
+		/* We must initialize all our variables to NULL, so that
+		   `FREE_VARIABLES' doesn't try to free them.  */
+		regstart = regend = old_regstart = old_regend = best_regstart
+			= best_regend = reg_dummy = NULL;
+		reg_info = reg_info_dummy = (register_info_type *) NULL;
+	}
+#endif							/* MATCH_MAY_ALLOCATE */
+
+	/* The starting position is bogus.  */
+	if (pos < 0 || pos > size1 + size2) {
+		FREE_VARIABLES();
+		return -1;
+	}
+
+	/* Initialize subexpression text positions to -1 to mark ones that no
+	   start_memory/stop_memory has been seen for. Also initialize the
+	   register information struct.  */
+	for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+		regstart[mcnt] = regend[mcnt]
+			= old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
+
+		REG_MATCH_NULL_STRING_P(reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
+		IS_ACTIVE(reg_info[mcnt]) = 0;
+		MATCHED_SOMETHING(reg_info[mcnt]) = 0;
+		EVER_MATCHED_SOMETHING(reg_info[mcnt]) = 0;
+	}
+
+	/* We move `string1' into `string2' if the latter's empty -- but not if
+	   `string1' is null.  */
+	if (size2 == 0 && string1 != NULL) {
+		string2 = string1;
+		size2 = size1;
+		string1 = 0;
+		size1 = 0;
+	}
+	end1 = string1 + size1;
+	end2 = string2 + size2;
+
+	/* Compute where to stop matching, within the two strings.  */
+	if (stop <= size1) {
+		end_match_1 = string1 + stop;
+		end_match_2 = string2;
+	} else {
+		end_match_1 = end1;
+		end_match_2 = string2 + stop - size1;
+	}
+
+	/* `p' scans through the pattern as `d' scans through the data.
+	   `dend' is the end of the input string that `d' points within.  `d'
+	   is advanced into the following input string whenever necessary, but
+	   this happens before fetching; therefore, at the beginning of the
+	   loop, `d' can be pointing at the end of a string, but it cannot
+	   equal `string2'.  */
+	if (size1 > 0 && pos <= size1) {
+		d = string1 + pos;
+		dend = end_match_1;
+	} else {
+		d = string2 + pos - size1;
+		dend = end_match_2;
+	}
+
+	DEBUG_PRINT1("The compiled pattern is:\n");
+	DEBUG_PRINT_COMPILED_PATTERN(bufp, p, pend);
+	DEBUG_PRINT1("The string to match is: `");
+	DEBUG_PRINT_DOUBLE_STRING(d, string1, size1, string2, size2);
+	DEBUG_PRINT1("'\n");
+
+	/* This loops over pattern commands.  It exits by returning from the
+	   function if the match is complete, or it drops through if the match
+	   fails at this starting point in the input data.  */
+	for (;;) {
+#ifdef _LIBC
+		DEBUG_PRINT2("\n%p: ", p);
+#else
+		DEBUG_PRINT2("\n0x%x: ", p);
+#endif
+
+		if (p == pend) {		/* End of pattern means we might have succeeded.  */
+			DEBUG_PRINT1("end of pattern ... ");
+
+			/* If we haven't matched the entire string, and we want the
+			   longest match, try backtracking.  */
+			if (d != end_match_2) {
+				/* 1 if this match ends in the same string (string1 or string2)
+				   as the best previous match.  */
+				boolean same_str_p = (FIRST_STRING_P(match_end)
+									  == MATCHING_IN_FIRST_STRING);
+
+				/* 1 if this match is the best seen so far.  */
+				boolean best_match_p;
+
+				/* AIX compiler got confused when this was combined
+				   with the previous declaration.  */
+				if (same_str_p)
+					best_match_p = d > match_end;
+				else
+					best_match_p = !MATCHING_IN_FIRST_STRING;
+
+				DEBUG_PRINT1("backtracking.\n");
+
+				if (!FAIL_STACK_EMPTY()) {	/* More failure points to try.  */
+
+					/* If exceeds best match so far, save it.  */
+					if (!best_regs_set || best_match_p) {
+						best_regs_set = true;
+						match_end = d;
+
+						DEBUG_PRINT1("\nSAVING match as best so far.\n");
+
+						for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+							best_regstart[mcnt] = regstart[mcnt];
+							best_regend[mcnt] = regend[mcnt];
+						}
+					}
+					goto fail;
+				}
+
+				/* If no failure points, don't restore garbage.  And if
+				   last match is real best match, don't restore second
+				   best one. */
+				else if (best_regs_set && !best_match_p) {
+				  restore_best_regs:
+					/* Restore best match.  It may happen that `dend ==
+					   end_match_1' while the restored d is in string2.
+					   For example, the pattern `x.*y.*z' against the
+					   strings `x-' and `y-z-', if the two strings are
+					   not consecutive in memory.  */
+					DEBUG_PRINT1("Restoring best registers.\n");
+
+					d = match_end;
+					dend = ((d >= string1 && d <= end1)
+							? end_match_1 : end_match_2);
+
+					for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
+						regstart[mcnt] = best_regstart[mcnt];
+						regend[mcnt] = best_regend[mcnt];
+					}
+				}
+			}
+			/* d != end_match_2 */
+		  succeed_label:
+			DEBUG_PRINT1("Accepting match.\n");
+
+			/* If caller wants register contents data back, do it.  */
+			if (regs && !bufp->no_sub) {
+				/* Have the register data arrays been allocated?  */
+				if (bufp->regs_allocated == REGS_UNALLOCATED) {	/* No.  So allocate them with malloc.  We need one
+																   extra element beyond `num_regs' for the `-1' marker
+																   GNU code uses.  */
+					regs->num_regs = MAX(RE_NREGS, num_regs + 1);
+					regs->start = TALLOC(regs->num_regs, regoff_t);
+					regs->end = TALLOC(regs->num_regs, regoff_t);
+					if (regs->start == NULL || regs->end == NULL) {
+						FREE_VARIABLES();
+						return -2;
+					}
+					bufp->regs_allocated = REGS_REALLOCATE;
+				} else if (bufp->regs_allocated == REGS_REALLOCATE) {	/* Yes.  If we need more elements than were already
+																		   allocated, reallocate them.  If we need fewer, just
+																		   leave it alone.  */
+					if (regs->num_regs < num_regs + 1) {
+						regs->num_regs = num_regs + 1;
+						RETALLOC(regs->start, regs->num_regs, regoff_t);
+						RETALLOC(regs->end, regs->num_regs, regoff_t);
+						if (regs->start == NULL || regs->end == NULL) {
+							FREE_VARIABLES();
+							return -2;
+						}
+					}
+				} else {
+					/* These braces fend off a "empty body in an else-statement"
+					   warning under GCC when assert expands to nothing.  */
+					assert(bufp->regs_allocated == REGS_FIXED);
+				}
+
+				/* Convert the pointer data in `regstart' and `regend' to
+				   indices.  Register zero has to be set differently,
+				   since we haven't kept track of any info for it.  */
+				if (regs->num_regs > 0) {
+					regs->start[0] = pos;
+					regs->end[0] = (MATCHING_IN_FIRST_STRING
+									? ((regoff_t) (d - string1))
+									: ((regoff_t) (d - string2 + size1)));
+				}
+
+				/* Go through the first `min (num_regs, regs->num_regs)'
+				   registers, since that is all we initialized.  */
+				for (mcnt = 1;
+					 (unsigned) mcnt < MIN(num_regs, regs->num_regs);
+					 mcnt++) {
+					if (REG_UNSET(regstart[mcnt])
+						|| REG_UNSET(regend[mcnt])) regs->start[mcnt] =
+							regs->end[mcnt] = -1;
+					else {
+						regs->start[mcnt]
+							= (regoff_t) POINTER_TO_OFFSET(regstart[mcnt]);
+						regs->end[mcnt]
+							= (regoff_t) POINTER_TO_OFFSET(regend[mcnt]);
+					}
+				}
+
+				/* If the regs structure we return has more elements than
+				   were in the pattern, set the extra elements to -1.  If
+				   we (re)allocated the registers, this is the case,
+				   because we always allocate enough to have at least one
+				   -1 at the end.  */
+				for (mcnt = num_regs; (unsigned) mcnt < regs->num_regs;
+					 mcnt++)
+					regs->start[mcnt] = regs->end[mcnt] = -1;
+			}
+			/* regs && !bufp->no_sub */
+			DEBUG_PRINT4
+				("%u failure points pushed, %u popped (%u remain).\n",
+				 nfailure_points_pushed, nfailure_points_popped,
+				 nfailure_points_pushed - nfailure_points_popped);
+			DEBUG_PRINT2("%u registers pushed.\n", num_regs_pushed);
+
+			mcnt = d - pos - (MATCHING_IN_FIRST_STRING
+							  ? string1 : string2 - size1);
+
+			DEBUG_PRINT2("Returning %d from re_match_2.\n", mcnt);
+
+			FREE_VARIABLES();
+			return mcnt;
+		}
+
+		/* Otherwise match next pattern command.  */
+		switch (SWITCH_ENUM_CAST((re_opcode_t) * p++)) {
+			/* Ignore these.  Used to ignore the n of succeed_n's which
+			   currently have n == 0.  */
+		case no_op:
+			DEBUG_PRINT1("EXECUTING no_op.\n");
+			break;
+
+		case succeed:
+			DEBUG_PRINT1("EXECUTING succeed.\n");
+			goto succeed_label;
+
+			/* Match the next n pattern characters exactly.  The following
+			   byte in the pattern defines n, and the n bytes after that
+			   are the characters to match.  */
+		case exactn:
+			mcnt = *p++;
+			DEBUG_PRINT2("EXECUTING exactn %d.\n", mcnt);
+
+			/* This is written out as an if-else so we don't waste time
+			   testing `translate' inside the loop.  */
+			if (translate) {
+				do {
+					PREFETCH();
+					if ((unsigned char) translate[(unsigned char) *d++]
+						!= (unsigned char) *p++)
+						goto fail;
+				}
+				while (--mcnt);
+			} else {
+				do {
+					PREFETCH();
+					if (*d++ != (char) *p++)
+						goto fail;
+				}
+				while (--mcnt);
+			}
+			SET_REGS_MATCHED();
+			break;
+
+
+			/* Match any character except possibly a newline or a null.  */
+		case anychar:
+			DEBUG_PRINT1("EXECUTING anychar.\n");
+
+			PREFETCH();
+
+			if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE(*d) == '\n')
+				|| (bufp->syntax & RE_DOT_NOT_NULL
+					&& TRANSLATE(*d) == '\000')) goto fail;
+
+			SET_REGS_MATCHED();
+			DEBUG_PRINT2("  Matched `%d'.\n", *d);
+			d++;
+			break;
+
+
+		case charset:
+		case charset_not:
+		{
+			register unsigned char c;
+			boolean not = (re_opcode_t) * (p - 1) == charset_not;
+
+			DEBUG_PRINT2("EXECUTING charset%s.\n", not ? "_not" : "");
+
+			PREFETCH();
+			c = TRANSLATE(*d);	/* The character to match.  */
+
+			/* Cast to `unsigned' instead of `unsigned char' in case the
+			   bit list is a full 32 bytes long.  */
+			if (c < (unsigned) (*p * BYTEWIDTH)
+				&& p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
+				not = !not;
+
+			p += 1 + *p;
+
+			if (!not)
+				goto fail;
+
+			SET_REGS_MATCHED();
+			d++;
+			break;
+		}
+
+
+			/* The beginning of a group is represented by start_memory.
+			   The arguments are the register number in the next byte, and the
+			   number of groups inner to this one in the next.  The text
+			   matched within the group is recorded (in the internal
+			   registers data structure) under the register number.  */
+		case start_memory:
+			DEBUG_PRINT3("EXECUTING start_memory %d (%d):\n", *p, p[1]);
+
+			/* Find out if this group can match the empty string.  */
+			p1 = p;				/* To send to group_match_null_string_p.  */
+
+			if (REG_MATCH_NULL_STRING_P(reg_info[*p]) ==
+				MATCH_NULL_UNSET_VALUE)
+					REG_MATCH_NULL_STRING_P(reg_info[*p]) =
+					group_match_null_string_p(&p1, pend, reg_info);
+
+			/* Save the position in the string where we were the last time
+			   we were at this open-group operator in case the group is
+			   operated upon by a repetition operator, e.g., with `(a*)*b'
+			   against `ab'; then we want to ignore where we are now in
+			   the string in case this attempt to match fails.  */
+			old_regstart[*p] = REG_MATCH_NULL_STRING_P(reg_info[*p])
+				? REG_UNSET(regstart[*p]) ? d : regstart[*p]
+				: regstart[*p];
+			DEBUG_PRINT2("  old_regstart: %d\n",
+						 POINTER_TO_OFFSET(old_regstart[*p]));
+
+			regstart[*p] = d;
+			DEBUG_PRINT2("  regstart: %d\n",
+						 POINTER_TO_OFFSET(regstart[*p]));
+
+			IS_ACTIVE(reg_info[*p]) = 1;
+			MATCHED_SOMETHING(reg_info[*p]) = 0;
+
+			/* Clear this whenever we change the register activity status.  */
+			set_regs_matched_done = 0;
+
+			/* This is the new highest active register.  */
+			highest_active_reg = *p;
+
+			/* If nothing was active before, this is the new lowest active
+			   register.  */
+			if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
+				lowest_active_reg = *p;
+
+			/* Move past the register number and inner group count.  */
+			p += 2;
+			just_past_start_mem = p;
+
+			break;
+
+
+			/* The stop_memory opcode represents the end of a group.  Its
+			   arguments are the same as start_memory's: the register
+			   number, and the number of inner groups.  */
+		case stop_memory:
+			DEBUG_PRINT3("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
+
+			/* We need to save the string position the last time we were at
+			   this close-group operator in case the group is operated
+			   upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
+			   against `aba'; then we want to ignore where we are now in
+			   the string in case this attempt to match fails.  */
+			old_regend[*p] = REG_MATCH_NULL_STRING_P(reg_info[*p])
+				? REG_UNSET(regend[*p]) ? d : regend[*p]
+				: regend[*p];
+			DEBUG_PRINT2("      old_regend: %d\n",
+						 POINTER_TO_OFFSET(old_regend[*p]));
+
+			regend[*p] = d;
+			DEBUG_PRINT2("      regend: %d\n",
+						 POINTER_TO_OFFSET(regend[*p]));
+
+			/* This register isn't active anymore.  */
+			IS_ACTIVE(reg_info[*p]) = 0;
+
+			/* Clear this whenever we change the register activity status.  */
+			set_regs_matched_done = 0;
+
+			/* If this was the only register active, nothing is active
+			   anymore.  */
+			if (lowest_active_reg == highest_active_reg) {
+				lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+				highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+			} else {			/* We must scan for the new highest active register, since
+								   it isn't necessarily one less than now: consider
+								   (a(b)c(d(e)f)g).  When group 3 ends, after the f), the
+								   new highest active register is 1.  */
+				unsigned char r = *p - 1;
+
+				while (r > 0 && !IS_ACTIVE(reg_info[r]))
+					r--;
+
+				/* If we end up at register zero, that means that we saved
+				   the registers as the result of an `on_failure_jump', not
+				   a `start_memory', and we jumped to past the innermost
+				   `stop_memory'.  For example, in ((.)*) we save
+				   registers 1 and 2 as a result of the *, but when we pop
+				   back to the second ), we are at the stop_memory 1.
+				   Thus, nothing is active.  */
+				if (r == 0) {
+					lowest_active_reg = NO_LOWEST_ACTIVE_REG;
+					highest_active_reg = NO_HIGHEST_ACTIVE_REG;
+				} else
+					highest_active_reg = r;
+			}
+
+			/* If just failed to match something this time around with a
+			   group that's operated on by a repetition operator, try to
+			   force exit from the ``loop'', and restore the register
+			   information for this group that we had before trying this
+			   last match.  */
+			if ((!MATCHED_SOMETHING(reg_info[*p])
+				 || just_past_start_mem == p - 1)
+				&& (p + 2) < pend) {
+				boolean is_a_jump_n = false;
+
+				p1 = p + 2;
+				mcnt = 0;
+				switch ((re_opcode_t) * p1++) {
+				case jump_n:
+					is_a_jump_n = true;
+				case pop_failure_jump:
+				case maybe_pop_jump:
+				case jump:
+				case dummy_failure_jump:
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					if (is_a_jump_n)
+						p1 += 2;
+					break;
+
+				default:
+					/* do nothing */ ;
+				}
+				p1 += mcnt;
+
+				/* If the next operation is a jump backwards in the pattern
+				   to an on_failure_jump right before the start_memory
+				   corresponding to this stop_memory, exit from the loop
+				   by forcing a failure after pushing on the stack the
+				   on_failure_jump's jump in the pattern, and d.  */
+				if (mcnt < 0 && (re_opcode_t) * p1 == on_failure_jump
+					&& (re_opcode_t) p1[3] == start_memory && p1[4] == *p) {
+					/* If this group ever matched anything, then restore
+					   what its registers were before trying this last
+					   failed match, e.g., with `(a*)*b' against `ab' for
+					   regstart[1], and, e.g., with `((a*)*(b*)*)*'
+					   against `aba' for regend[3].
+
+					   Also restore the registers for inner groups for,
+					   e.g., `((a*)(b*))*' against `aba' (register 3 would
+					   otherwise get trashed).  */
+
+					if (EVER_MATCHED_SOMETHING(reg_info[*p])) {
+						unsigned r;
+
+						EVER_MATCHED_SOMETHING(reg_info[*p]) = 0;
+
+						/* Restore this and inner groups' (if any) registers.  */
+						for (r = *p;
+							 r < (unsigned) *p + (unsigned) *(p + 1); r++) {
+							regstart[r] = old_regstart[r];
+
+							/* xx why this test?  */
+							if (old_regend[r] >= regstart[r])
+								regend[r] = old_regend[r];
+						}
+					}
+					p1++;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					PUSH_FAILURE_POINT(p1 + mcnt, d, -2);
+
+					goto fail;
+				}
+			}
+
+			/* Move past the register number and the inner group count.  */
+			p += 2;
+			break;
+
+
+			/* \<digit> has been turned into a `duplicate' command which is
+			   followed by the numeric value of <digit> as the register number.  */
+		case duplicate:
+		{
+			register const char *d2, *dend2;
+			int regno = *p++;	/* Get which register to match against.  */
+
+			DEBUG_PRINT2("EXECUTING duplicate %d.\n", regno);
+
+			/* Can't back reference a group which we've never matched.  */
+			if (REG_UNSET(regstart[regno]) || REG_UNSET(regend[regno]))
+				goto fail;
+
+			/* Where in input to try to start matching.  */
+			d2 = regstart[regno];
+
+			/* Where to stop matching; if both the place to start and
+			   the place to stop matching are in the same string, then
+			   set to the place to stop, otherwise, for now have to use
+			   the end of the first string.  */
+
+			dend2 = ((FIRST_STRING_P(regstart[regno])
+					  == FIRST_STRING_P(regend[regno]))
+					 ? regend[regno] : end_match_1);
+			for (;;) {
+				/* If necessary, advance to next segment in register
+				   contents.  */
+				while (d2 == dend2) {
+					if (dend2 == end_match_2)
+						break;
+					if (dend2 == regend[regno])
+						break;
+
+					/* End of string1 => advance to string2. */
+					d2 = string2;
+					dend2 = regend[regno];
+				}
+				/* At end of register contents => success */
+				if (d2 == dend2)
+					break;
+
+				/* If necessary, advance to next segment in data.  */
+				PREFETCH();
+
+				/* How many characters left in this segment to match.  */
+				mcnt = dend - d;
+
+				/* Want how many consecutive characters we can match in
+				   one shot, so, if necessary, adjust the count.  */
+				if (mcnt > dend2 - d2)
+					mcnt = dend2 - d2;
+
+				/* Compare that many; failure if mismatch, else move
+				   past them.  */
+				if (translate ? bcmp_translate(d, d2, mcnt, translate)
+					: memcmp(d, d2, mcnt))
+					goto fail;
+				d += mcnt, d2 += mcnt;
+
+				/* Do this because we've match some characters.  */
+				SET_REGS_MATCHED();
+			}
+		}
+			break;
+
+
+			/* begline matches the empty string at the beginning of the string
+			   (unless `not_bol' is set in `bufp'), and, if
+			   `newline_anchor' is set, after newlines.  */
+		case begline:
+			DEBUG_PRINT1("EXECUTING begline.\n");
+
+			if (AT_STRINGS_BEG(d)) {
+				if (!bufp->not_bol)
+					break;
+			} else if (d[-1] == '\n' && bufp->newline_anchor) {
+				break;
+			}
+			/* In all other cases, we fail.  */
+			goto fail;
+
+
+			/* endline is the dual of begline.  */
+		case endline:
+			DEBUG_PRINT1("EXECUTING endline.\n");
+
+			if (AT_STRINGS_END(d)) {
+				if (!bufp->not_eol)
+					break;
+			}
+
+			/* We have to ``prefetch'' the next character.  */
+			else if ((d == end1 ? *string2 : *d) == '\n'
+					 && bufp->newline_anchor) {
+				break;
+			}
+			goto fail;
+
+
+			/* Match at the very beginning of the data.  */
+		case begbuf:
+			DEBUG_PRINT1("EXECUTING begbuf.\n");
+			if (AT_STRINGS_BEG(d))
+				break;
+			goto fail;
+
+
+			/* Match at the very end of the data.  */
+		case endbuf:
+			DEBUG_PRINT1("EXECUTING endbuf.\n");
+			if (AT_STRINGS_END(d))
+				break;
+			goto fail;
+
+
+			/* on_failure_keep_string_jump is used to optimize `.*\n'.  It
+			   pushes NULL as the value for the string on the stack.  Then
+			   `pop_failure_point' will keep the current value for the
+			   string, instead of restoring it.  To see why, consider
+			   matching `foo\nbar' against `.*\n'.  The .* matches the foo;
+			   then the . fails against the \n.  But the next thing we want
+			   to do is match the \n against the \n; if we restored the
+			   string value, we would be back at the foo.
+
+			   Because this is used only in specific cases, we don't need to
+			   check all the things that `on_failure_jump' does, to make
+			   sure the right things get saved on the stack.  Hence we don't
+			   share its code.  The only reason to push anything on the
+			   stack at all is that otherwise we would have to change
+			   `anychar's code to do something besides goto fail in this
+			   case; that seems worse than this.  */
+		case on_failure_keep_string_jump:
+			DEBUG_PRINT1("EXECUTING on_failure_keep_string_jump");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3(" %d (to %p):\n", mcnt, p + mcnt);
+#else
+			DEBUG_PRINT3(" %d (to 0x%x):\n", mcnt, p + mcnt);
+#endif
+
+			PUSH_FAILURE_POINT(p + mcnt, NULL, -2);
+			break;
+
+
+			/* Uses of on_failure_jump:
+
+			   Each alternative starts with an on_failure_jump that points
+			   to the beginning of the next alternative.  Each alternative
+			   except the last ends with a jump that in effect jumps past
+			   the rest of the alternatives.  (They really jump to the
+			   ending jump of the following alternative, because tensioning
+			   these jumps is a hassle.)
+
+			   Repeats start with an on_failure_jump that points past both
+			   the repetition text and either the following jump or
+			   pop_failure_jump back to this on_failure_jump.  */
+		case on_failure_jump:
+		  on_failure:
+			DEBUG_PRINT1("EXECUTING on_failure_jump");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3(" %d (to %p)", mcnt, p + mcnt);
+#else
+			DEBUG_PRINT3(" %d (to 0x%x)", mcnt, p + mcnt);
+#endif
+
+			/* If this on_failure_jump comes right before a group (i.e.,
+			   the original * applied to a group), save the information
+			   for that group and all inner ones, so that if we fail back
+			   to this point, the group's information will be correct.
+			   For example, in \(a*\)*\1, we need the preceding group,
+			   and in \(zz\(a*\)b*\)\2, we need the inner group.  */
+
+			/* We can't use `p' to check ahead because we push
+			   a failure point to `p + mcnt' after we do this.  */
+			p1 = p;
+
+			/* We need to skip no_op's before we look for the
+			   start_memory in case this on_failure_jump is happening as
+			   the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
+			   against aba.  */
+			while (p1 < pend && (re_opcode_t) * p1 == no_op)
+				p1++;
+
+			if (p1 < pend && (re_opcode_t) * p1 == start_memory) {
+				/* We have a new highest active register now.  This will
+				   get reset at the start_memory we are about to get to,
+				   but we will have saved all the registers relevant to
+				   this repetition op, as described above.  */
+				highest_active_reg = *(p1 + 1) + *(p1 + 2);
+				if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
+					lowest_active_reg = *(p1 + 1);
+			}
+
+			DEBUG_PRINT1(":\n");
+			PUSH_FAILURE_POINT(p + mcnt, d, -2);
+			break;
+
+
+			/* A smart repeat ends with `maybe_pop_jump'.
+			   We change it to either `pop_failure_jump' or `jump'.  */
+		case maybe_pop_jump:
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+			DEBUG_PRINT2("EXECUTING maybe_pop_jump %d.\n", mcnt);
+			{
+				register unsigned char *p2 = p;
+
+				/* Compare the beginning of the repeat with what in the
+				   pattern follows its end. If we can establish that there
+				   is nothing that they would both match, i.e., that we
+				   would have to backtrack because of (as in, e.g., `a*a')
+				   then we can change to pop_failure_jump, because we'll
+				   never have to backtrack.
+
+				   This is not true in the case of alternatives: in
+				   `(a|ab)*' we do need to backtrack to the `ab' alternative
+				   (e.g., if the string was `ab').  But instead of trying to
+				   detect that here, the alternative has put on a dummy
+				   failure point which is what we will end up popping.  */
+
+				/* Skip over open/close-group commands.
+				   If what follows this loop is a ...+ construct,
+				   look at what begins its body, since we will have to
+				   match at least one of that.  */
+				while (1) {
+					if (p2 + 2 < pend
+						&& ((re_opcode_t) * p2 == stop_memory
+							|| (re_opcode_t) * p2 == start_memory))
+						p2 += 3;
+					else if (p2 + 6 < pend
+							 && (re_opcode_t) * p2 == dummy_failure_jump)
+							p2 += 6;
+					else
+						break;
+				}
+
+				p1 = p + mcnt;
+				/* p1[0] ... p1[2] are the `on_failure_jump' corresponding
+				   to the `maybe_finalize_jump' of this case.  Examine what
+				   follows.  */
+
+				/* If we're at the end of the pattern, we can change.  */
+				if (p2 == pend) {
+					/* Consider what happens when matching ":\(.*\)"
+					   against ":/".  I don't really understand this code
+					   yet.  */
+					p[-3] = (unsigned char) pop_failure_jump;
+					DEBUG_PRINT1
+						("  End of pattern: change to `pop_failure_jump'.\n");
+				}
+
+				else if ((re_opcode_t) * p2 == exactn
+						 || (bufp->newline_anchor
+							 && (re_opcode_t) * p2 == endline)) {
+					register unsigned char c =
+						*p2 == (unsigned char) endline ? '\n' : p2[2];
+
+					if ((re_opcode_t) p1[3] == exactn && p1[5] != c) {
+						p[-3] = (unsigned char) pop_failure_jump;
+						DEBUG_PRINT3("  %c != %c => pop_failure_jump.\n",
+									 c, p1[5]);
+					}
+
+					else if ((re_opcode_t) p1[3] == charset
+							 || (re_opcode_t) p1[3] == charset_not) {
+						int not = (re_opcode_t) p1[3] == charset_not;
+
+						if (c < (unsigned char) (p1[4] * BYTEWIDTH)
+							&& p1[5 +
+								  c / BYTEWIDTH] & (1 << (c %
+														  BYTEWIDTH))) not
+								= !not;
+
+						/* `not' is equal to 1 if c would match, which means
+						   that we can't change to pop_failure_jump.  */
+						if (!not) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					}
+				} else if ((re_opcode_t) * p2 == charset) {
+					/* We win if the first character of the loop is not part
+					   of the charset.  */
+					if ((re_opcode_t) p1[3] == exactn
+						&& !((int) p2[1] * BYTEWIDTH > (int) p1[5]
+							 && (p2[2 + p1[5] / BYTEWIDTH]
+								 & (1 << (p1[5] % BYTEWIDTH))))) {
+						p[-3] = (unsigned char) pop_failure_jump;
+						DEBUG_PRINT1("  No match => pop_failure_jump.\n");
+					}
+
+					else if ((re_opcode_t) p1[3] == charset_not) {
+						int idx;
+
+						/* We win if the charset_not inside the loop
+						   lists every character listed in the charset after.  */
+						for (idx = 0; idx < (int) p2[1]; idx++)
+							if (!(p2[2 + idx] == 0 || (idx < (int) p1[4]
+													   &&
+													   ((p2
+														 [2 +
+														  idx] & ~p1[5 +
+																	 idx])
+														== 0))))
+								break;
+
+						if (idx == p2[1]) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					} else if ((re_opcode_t) p1[3] == charset) {
+						int idx;
+
+						/* We win if the charset inside the loop
+						   has no overlap with the one after the loop.  */
+						for (idx = 0;
+							 idx < (int) p2[1] && idx < (int) p1[4]; idx++)
+							if ((p2[2 + idx] & p1[5 + idx]) != 0)
+								break;
+
+						if (idx == p2[1] || idx == p1[4]) {
+							p[-3] = (unsigned char) pop_failure_jump;
+							DEBUG_PRINT1
+								("  No match => pop_failure_jump.\n");
+						}
+					}
+				}
+			}
+			p -= 2;				/* Point at relative address again.  */
+			if ((re_opcode_t) p[-1] != pop_failure_jump) {
+				p[-1] = (unsigned char) jump;
+				DEBUG_PRINT1("  Match => jump.\n");
+				goto unconditional_jump;
+			}
+			/* Note fall through.  */
+
+
+			/* The end of a simple repeat has a pop_failure_jump back to
+			   its matching on_failure_jump, where the latter will push a
+			   failure point.  The pop_failure_jump takes off failure
+			   points put on by this pop_failure_jump's matching
+			   on_failure_jump; we got through the pattern to here from the
+			   matching on_failure_jump, so didn't fail.  */
+		case pop_failure_jump:
+		{
+			/* We need to pass separate storage for the lowest and
+			   highest registers, even though we don't care about the
+			   actual values.  Otherwise, we will restore only one
+			   register from the stack, since lowest will == highest in
+			   `pop_failure_point'.  */
+			active_reg_t dummy_low_reg, dummy_high_reg;
+			unsigned char *pdummy;
+			const char *sdummy;
+
+			DEBUG_PRINT1("EXECUTING pop_failure_jump.\n");
+			POP_FAILURE_POINT(sdummy, pdummy,
+							  dummy_low_reg, dummy_high_reg,
+							  reg_dummy, reg_dummy, reg_info_dummy);
+		}
+			/* Note fall through.  */
+
+		  unconditional_jump:
+#ifdef _LIBC
+			DEBUG_PRINT2("\n%p: ", p);
+#else
+			DEBUG_PRINT2("\n0x%x: ", p);
+#endif
+			/* Note fall through.  */
+
+			/* Unconditionally jump (without popping any failure points).  */
+		case jump:
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);	/* Get the amount to jump.  */
+			DEBUG_PRINT2("EXECUTING jump %d ", mcnt);
+			p += mcnt;			/* Do the jump.  */
+#ifdef _LIBC
+			DEBUG_PRINT2("(to %p).\n", p);
+#else
+			DEBUG_PRINT2("(to 0x%x).\n", p);
+#endif
+			break;
+
+
+			/* We need this opcode so we can detect where alternatives end
+			   in `group_match_null_string_p' et al.  */
+		case jump_past_alt:
+			DEBUG_PRINT1("EXECUTING jump_past_alt.\n");
+			goto unconditional_jump;
+
+
+			/* Normally, the on_failure_jump pushes a failure point, which
+			   then gets popped at pop_failure_jump.  We will end up at
+			   pop_failure_jump, also, and with a pattern of, say, `a+', we
+			   are skipping over the on_failure_jump, so we have to push
+			   something meaningless for pop_failure_jump to pop.  */
+		case dummy_failure_jump:
+			DEBUG_PRINT1("EXECUTING dummy_failure_jump.\n");
+			/* It doesn't matter what we push for the string here.  What
+			   the code at `fail' tests is the value for the pattern.  */
+			PUSH_FAILURE_POINT(NULL, NULL, -2);
+			goto unconditional_jump;
+
+
+			/* At the end of an alternative, we need to push a dummy failure
+			   point in case we are followed by a `pop_failure_jump', because
+			   we don't want the failure point for the alternative to be
+			   popped.  For example, matching `(a|ab)*' against `aab'
+			   requires that we match the `ab' alternative.  */
+		case push_dummy_failure:
+			DEBUG_PRINT1("EXECUTING push_dummy_failure.\n");
+			/* See comments just above at `dummy_failure_jump' about the
+			   two zeroes.  */
+			PUSH_FAILURE_POINT(NULL, NULL, -2);
+			break;
+
+			/* Have to succeed matching what follows at least n times.
+			   After that, handle like `on_failure_jump'.  */
+		case succeed_n:
+			EXTRACT_NUMBER(mcnt, p + 2);
+			DEBUG_PRINT2("EXECUTING succeed_n %d.\n", mcnt);
+
+			assert(mcnt >= 0);
+			/* Originally, this is how many times we HAVE to succeed.  */
+			if (mcnt > 0) {
+				mcnt--;
+				p += 2;
+				STORE_NUMBER_AND_INCR(p, mcnt);
+#ifdef _LIBC
+				DEBUG_PRINT3("  Setting %p to %d.\n", p - 2, mcnt);
+#else
+				DEBUG_PRINT3("  Setting 0x%x to %d.\n", p - 2, mcnt);
+#endif
+			} else if (mcnt == 0) {
+#ifdef _LIBC
+				DEBUG_PRINT2("  Setting two bytes from %p to no_op.\n",
+							 p + 2);
+#else
+				DEBUG_PRINT2("  Setting two bytes from 0x%x to no_op.\n",
+							 p + 2);
+#endif
+				p[2] = (unsigned char) no_op;
+				p[3] = (unsigned char) no_op;
+				goto on_failure;
+			}
+			break;
+
+		case jump_n:
+			EXTRACT_NUMBER(mcnt, p + 2);
+			DEBUG_PRINT2("EXECUTING jump_n %d.\n", mcnt);
+
+			/* Originally, this is how many times we CAN jump.  */
+			if (mcnt) {
+				mcnt--;
+				STORE_NUMBER(p + 2, mcnt);
+#ifdef _LIBC
+				DEBUG_PRINT3("  Setting %p to %d.\n", p + 2, mcnt);
+#else
+				DEBUG_PRINT3("  Setting 0x%x to %d.\n", p + 2, mcnt);
+#endif
+				goto unconditional_jump;
+			}
+			/* If don't have to jump any more, skip over the rest of command.  */
+			else
+				p += 4;
+			break;
+
+		case set_number_at:
+		{
+			DEBUG_PRINT1("EXECUTING set_number_at.\n");
+
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+			p1 = p + mcnt;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p);
+#ifdef _LIBC
+			DEBUG_PRINT3("  Setting %p to %d.\n", p1, mcnt);
+#else
+			DEBUG_PRINT3("  Setting 0x%x to %d.\n", p1, mcnt);
+#endif
+			STORE_NUMBER(p1, mcnt);
+			break;
+		}
+
+#if 0
+			/* The DEC Alpha C compiler 3.x generates incorrect code for the
+			   test  WORDCHAR_P (d - 1) != WORDCHAR_P (d)  in the expansion of
+			   AT_WORD_BOUNDARY, so this code is disabled.  Expanding the
+			   macro and introducing temporary variables works around the bug.  */
+
+		case wordbound:
+			DEBUG_PRINT1("EXECUTING wordbound.\n");
+			if (AT_WORD_BOUNDARY(d))
+				break;
+			goto fail;
+
+		case notwordbound:
+			DEBUG_PRINT1("EXECUTING notwordbound.\n");
+			if (AT_WORD_BOUNDARY(d))
+				goto fail;
+			break;
+#else
+		case wordbound:
+		{
+			boolean prevchar, thischar;
+
+			DEBUG_PRINT1("EXECUTING wordbound.\n");
+			if (AT_STRINGS_BEG(d) || AT_STRINGS_END(d))
+				break;
+
+			prevchar = WORDCHAR_P(d - 1);
+			thischar = WORDCHAR_P(d);
+			if (prevchar != thischar)
+				break;
+			goto fail;
+		}
+
+		case notwordbound:
+		{
+			boolean prevchar, thischar;
+
+			DEBUG_PRINT1("EXECUTING notwordbound.\n");
+			if (AT_STRINGS_BEG(d) || AT_STRINGS_END(d))
+				goto fail;
+
+			prevchar = WORDCHAR_P(d - 1);
+			thischar = WORDCHAR_P(d);
+			if (prevchar != thischar)
+				goto fail;
+			break;
+		}
+#endif
+
+		case wordbeg:
+			DEBUG_PRINT1("EXECUTING wordbeg.\n");
+			if (WORDCHAR_P(d) && (AT_STRINGS_BEG(d) || !WORDCHAR_P(d - 1)))
+				break;
+			goto fail;
+
+		case wordend:
+			DEBUG_PRINT1("EXECUTING wordend.\n");
+			if (!AT_STRINGS_BEG(d) && WORDCHAR_P(d - 1)
+				&& (!WORDCHAR_P(d) || AT_STRINGS_END(d)))
+				break;
+			goto fail;
+
+#ifdef emacs
+		case before_dot:
+			DEBUG_PRINT1("EXECUTING before_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) >= point)
+				goto fail;
+			break;
+
+		case at_dot:
+			DEBUG_PRINT1("EXECUTING at_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) != point)
+				goto fail;
+			break;
+
+		case after_dot:
+			DEBUG_PRINT1("EXECUTING after_dot.\n");
+			if (PTR_CHAR_POS((unsigned char *) d) <= point)
+				goto fail;
+			break;
+
+		case syntaxspec:
+			DEBUG_PRINT2("EXECUTING syntaxspec %d.\n", mcnt);
+			mcnt = *p++;
+			goto matchsyntax;
+
+		case wordchar:
+			DEBUG_PRINT1("EXECUTING Emacs wordchar.\n");
+			mcnt = (int) Sword;
+		  matchsyntax:
+			PREFETCH();
+			/* Can't use *d++ here; SYNTAX may be an unsafe macro.  */
+			d++;
+			if (SYNTAX(d[-1]) != (enum syntaxcode) mcnt)
+				goto fail;
+			SET_REGS_MATCHED();
+			break;
+
+		case notsyntaxspec:
+			DEBUG_PRINT2("EXECUTING notsyntaxspec %d.\n", mcnt);
+			mcnt = *p++;
+			goto matchnotsyntax;
+
+		case notwordchar:
+			DEBUG_PRINT1("EXECUTING Emacs notwordchar.\n");
+			mcnt = (int) Sword;
+		  matchnotsyntax:
+			PREFETCH();
+			/* Can't use *d++ here; SYNTAX may be an unsafe macro.  */
+			d++;
+			if (SYNTAX(d[-1]) == (enum syntaxcode) mcnt)
+				goto fail;
+			SET_REGS_MATCHED();
+			break;
+
+#else							/* not emacs */
+		case wordchar:
+			DEBUG_PRINT1("EXECUTING non-Emacs wordchar.\n");
+			PREFETCH();
+			if (!WORDCHAR_P(d))
+				goto fail;
+			SET_REGS_MATCHED();
+			d++;
+			break;
+
+		case notwordchar:
+			DEBUG_PRINT1("EXECUTING non-Emacs notwordchar.\n");
+			PREFETCH();
+			if (WORDCHAR_P(d))
+				goto fail;
+			SET_REGS_MATCHED();
+			d++;
+			break;
+#endif							/* not emacs */
+
+		default:
+			abort();
+		}
+		continue;				/* Successfully executed one pattern command; keep going.  */
+
+
+		/* We goto here if a matching operation fails. */
+	  fail:
+		if (!FAIL_STACK_EMPTY()) {	/* A restart point is known.  Restore to that state.  */
+			DEBUG_PRINT1("\nFAIL:\n");
+			POP_FAILURE_POINT(d, p,
+							  lowest_active_reg, highest_active_reg,
+							  regstart, regend, reg_info);
+
+			/* If this failure point is a dummy, try the next one.  */
+			if (!p)
+				goto fail;
+
+			/* If we failed to the end of the pattern, don't examine *p.  */
+			assert(p <= pend);
+			if (p < pend) {
+				boolean is_a_jump_n = false;
+
+				/* If failed to a backwards jump that's part of a repetition
+				   loop, need to pop this failure point and use the next one.  */
+				switch ((re_opcode_t) * p) {
+				case jump_n:
+					is_a_jump_n = true;
+				case maybe_pop_jump:
+				case pop_failure_jump:
+				case jump:
+					p1 = p + 1;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					p1 += mcnt;
+
+					if ((is_a_jump_n && (re_opcode_t) * p1 == succeed_n)
+						|| (!is_a_jump_n
+							&& (re_opcode_t) * p1 == on_failure_jump))
+							goto fail;
+					break;
+				default:
+					/* do nothing */ ;
+				}
+			}
+
+			if (d >= string1 && d <= end1)
+				dend = end_match_1;
+		} else
+			break;				/* Matching at this starting point really fails.  */
+	}							/* for (;;) */
+
+	if (best_regs_set)
+		goto restore_best_regs;
+
+	FREE_VARIABLES();
+
+	return -1;					/* Failure to match.  */
+}								/* re_match_2 */
+
+/* Subroutine definitions for re_match_2.  */
+
+
+/* We are passed P pointing to a register number after a start_memory.
+
+   Return true if the pattern up to the corresponding stop_memory can
+   match the empty string, and false otherwise.
+
+   If we find the matching stop_memory, sets P to point to one past its number.
+   Otherwise, sets P to an undefined byte less than or equal to END.
+
+   We don't handle duplicates properly (yet).  */
+
+static boolean group_match_null_string_p(p, end, reg_info)
+unsigned char **p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+
+	/* Point to after the args to the start_memory.  */
+	unsigned char *p1 = *p + 2;
+
+	while (p1 < end) {
+		/* Skip over opcodes that can match nothing, and return true or
+		   false, as appropriate, when we get to one that can't, or to the
+		   matching stop_memory.  */
+
+		switch ((re_opcode_t) * p1) {
+			/* Could be either a loop or a series of alternatives.  */
+		case on_failure_jump:
+			p1++;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+
+			/* If the next operation is not a jump backwards in the
+			   pattern.  */
+
+			if (mcnt >= 0) {
+				/* Go through the on_failure_jumps of the alternatives,
+				   seeing if any of the alternatives cannot match nothing.
+				   The last alternative starts with only a jump,
+				   whereas the rest start with on_failure_jump and end
+				   with a jump, e.g., here is the pattern for `a|b|c':
+
+				   /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
+				   /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
+				   /exactn/1/c
+
+				   So, we have to first go through the first (n-1)
+				   alternatives and then deal with the last one separately.  */
+
+
+				/* Deal with the first (n-1) alternatives, which start
+				   with an on_failure_jump (see above) that jumps to right
+				   past a jump_past_alt.  */
+
+				while ((re_opcode_t) p1[mcnt - 3] == jump_past_alt) {
+					/* `mcnt' holds how many bytes long the alternative
+					   is, including the ending `jump_past_alt' and
+					   its number.  */
+
+					if (!alt_match_null_string_p(p1, p1 + mcnt - 3,
+												 reg_info)) return false;
+
+					/* Move to right after this alternative, including the
+					   jump_past_alt.  */
+					p1 += mcnt;
+
+					/* Break if it's the beginning of an n-th alternative
+					   that doesn't begin with an on_failure_jump.  */
+					if ((re_opcode_t) * p1 != on_failure_jump)
+						break;
+
+					/* Still have to check that it's not an n-th
+					   alternative that starts with an on_failure_jump.  */
+					p1++;
+					EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+					if ((re_opcode_t) p1[mcnt - 3] != jump_past_alt) {
+						/* Get to the beginning of the n-th alternative.  */
+						p1 -= 3;
+						break;
+					}
+				}
+
+				/* Deal with the last alternative: go back and get number
+				   of the `jump_past_alt' just before it.  `mcnt' contains
+				   the length of the alternative.  */
+				EXTRACT_NUMBER(mcnt, p1 - 2);
+
+				if (!alt_match_null_string_p(p1, p1 + mcnt, reg_info))
+					return false;
+
+				p1 += mcnt;		/* Get past the n-th alternative.  */
+			}					/* if mcnt > 0 */
+			break;
+
+
+		case stop_memory:
+			assert(p1[1] == **p);
+			*p = p1 + 2;
+			return true;
+
+
+		default:
+			if (!common_op_match_null_string_p(&p1, end, reg_info))
+				return false;
+		}
+	}							/* while p1 < end */
+
+	return false;
+}								/* group_match_null_string_p */
+
+
+/* Similar to group_match_null_string_p, but doesn't deal with alternatives:
+   It expects P to be the first byte of a single alternative and END one
+   byte past the last. The alternative can contain groups.  */
+
+static boolean alt_match_null_string_p(p, end, reg_info)
+unsigned char *p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+	unsigned char *p1 = p;
+
+	while (p1 < end) {
+		/* Skip over opcodes that can match nothing, and break when we get
+		   to one that can't.  */
+
+		switch ((re_opcode_t) * p1) {
+			/* It's a loop.  */
+		case on_failure_jump:
+			p1++;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+			p1 += mcnt;
+			break;
+
+		default:
+			if (!common_op_match_null_string_p(&p1, end, reg_info))
+				return false;
+		}
+	}							/* while p1 < end */
+
+	return true;
+}								/* alt_match_null_string_p */
+
+
+/* Deals with the ops common to group_match_null_string_p and
+   alt_match_null_string_p.
+
+   Sets P to one after the op and its arguments, if any.  */
+
+static boolean common_op_match_null_string_p(p, end, reg_info)
+unsigned char **p, *end;
+register_info_type *reg_info;
+{
+	int mcnt;
+	boolean ret;
+	int reg_no;
+	unsigned char *p1 = *p;
+
+	switch ((re_opcode_t) * p1++) {
+	case no_op:
+	case begline:
+	case endline:
+	case begbuf:
+	case endbuf:
+	case wordbeg:
+	case wordend:
+	case wordbound:
+	case notwordbound:
+#ifdef emacs
+	case before_dot:
+	case at_dot:
+	case after_dot:
+#endif
+		break;
+
+	case start_memory:
+		reg_no = *p1;
+		assert(reg_no > 0 && reg_no <= MAX_REGNUM);
+		ret = group_match_null_string_p(&p1, end, reg_info);
+
+		/* Have to set this here in case we're checking a group which
+		   contains a group and a back reference to it.  */
+
+		if (REG_MATCH_NULL_STRING_P(reg_info[reg_no]) ==
+			MATCH_NULL_UNSET_VALUE)
+				REG_MATCH_NULL_STRING_P(reg_info[reg_no]) = ret;
+
+		if (!ret)
+			return false;
+		break;
+
+		/* If this is an optimized succeed_n for zero times, make the jump.  */
+	case jump:
+		EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+		if (mcnt >= 0)
+			p1 += mcnt;
+		else
+			return false;
+		break;
+
+	case succeed_n:
+		/* Get to the number of times to succeed.  */
+		p1 += 2;
+		EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+
+		if (mcnt == 0) {
+			p1 -= 4;
+			EXTRACT_NUMBER_AND_INCR(mcnt, p1);
+			p1 += mcnt;
+		} else
+			return false;
+		break;
+
+	case duplicate:
+		if (!REG_MATCH_NULL_STRING_P(reg_info[*p1]))
+			return false;
+		break;
+
+	case set_number_at:
+		p1 += 4;
+
+	default:
+		/* All other opcodes mean we cannot match the empty string.  */
+		return false;
+	}
+
+	*p = p1;
+	return true;
+}								/* common_op_match_null_string_p */
+
+
+/* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
+   bytes; nonzero otherwise.  */
+
+static int bcmp_translate(s1, s2, len, translate)
+const char *s1, *s2;
+register int len;
+RE_TRANSLATE_TYPE translate;
+{
+	register const unsigned char *p1 = (const unsigned char *) s1;
+	register const unsigned char *p2 = (const unsigned char *) s2;
+
+	while (len) {
+		if (translate[*p1++] != translate[*p2++])
+			return 1;
+		len--;
+	}
+	return 0;
+}
+
+/* Entry points for GNU code.  */
+
+/* re_compile_pattern is the GNU regular expression compiler: it
+   compiles PATTERN (of length SIZE) and puts the result in BUFP.
+   Returns 0 if the pattern was valid, otherwise an error string.
+
+   Assumes the `allocated' (and perhaps `buffer') and `translate' fields
+   are set in BUFP on entry.
+
+   We call regex_compile to do the actual compilation.  */
+
+const char *re_compile_pattern(pattern, length, bufp)
+const char *pattern;
+size_t length;
+struct re_pattern_buffer *bufp;
+{
+	reg_errcode_t ret;
+
+	/* GNU code is written to assume at least RE_NREGS registers will be set
+	   (and at least one extra will be -1).  */
+	bufp->regs_allocated = REGS_UNALLOCATED;
+
+	/* And GNU code determines whether or not to get register information
+	   by passing null for the REGS argument to re_match, etc., not by
+	   setting no_sub.  */
+	bufp->no_sub = 0;
+
+	/* Match anchors at newline.  */
+	bufp->newline_anchor = 1;
+
+	ret = regex_compile(pattern, length, re_syntax_options, bufp);
+
+	if (!ret)
+		return NULL;
+	return gettext(re_error_msgid + re_error_msgid_idx[(int) ret]);
+}
+
+#ifdef _LIBC
+weak_alias(__re_compile_pattern, re_compile_pattern)
+#endif
+/* Entry points compatible with 4.2 BSD regex library.  We don't define
+   them unless specifically requested.  */
+#if defined _REGEX_RE_COMP || defined _LIBC
+/* BSD has one and only one pattern buffer.  */
+static struct re_pattern_buffer re_comp_buf;
+
+char *
+#ifdef _LIBC
+/* Make these definitions weak in libc, so POSIX programs can redefine
+   these names if they don't use our functions, and still use
+   regcomp/regexec below without link errors.  */ weak_function
+#endif
+re_comp(s)
+const char *s;
+{
+	reg_errcode_t ret;
+
+	if (!s) {
+		if (!re_comp_buf.buffer)
+			return gettext("No previous regular expression");
+		return 0;
+	}
+
+	if (!re_comp_buf.buffer) {
+		re_comp_buf.buffer = (unsigned char *) malloc(200);
+		if (re_comp_buf.buffer == NULL)
+			return (char *) gettext(re_error_msgid
+									+
+									re_error_msgid_idx[(int) REG_ESPACE]);
+		re_comp_buf.allocated = 200;
+
+		re_comp_buf.fastmap = (char *) malloc(1 << BYTEWIDTH);
+		if (re_comp_buf.fastmap == NULL)
+			return (char *) gettext(re_error_msgid
+									+
+									re_error_msgid_idx[(int) REG_ESPACE]);
+	}
+
+	/* Since `re_exec' always passes NULL for the `regs' argument, we
+	   don't need to initialize the pattern buffer fields which affect it.  */
+
+	/* Match anchors at newlines.  */
+	re_comp_buf.newline_anchor = 1;
+
+	ret = regex_compile(s, strlen(s), re_syntax_options, &re_comp_buf);
+
+	if (!ret)
+		return NULL;
+
+	/* Yes, we're discarding `const' here if !HAVE_LIBINTL.  */
+	return (char *) gettext(re_error_msgid +
+							re_error_msgid_idx[(int) ret]);
+}
+
+
+int
+#ifdef _LIBC
+ weak_function
+#endif
+re_exec(s)
+const char *s;
+{
+	const int len = strlen(s);
+
+	return
+		0 <= re_search(&re_comp_buf, s, len, 0, len,
+					   (struct re_registers *) 0);
+}
+
+#endif							/* _REGEX_RE_COMP */
+
+/* POSIX.2 functions.  Don't define these for Emacs.  */
+
+#ifndef emacs
+
+/* regcomp takes a regular expression as a string and compiles it.
+
+   PREG is a regex_t *.  We do not expect any fields to be initialized,
+   since POSIX says we shouldn't.  Thus, we set
+
+     `buffer' to the compiled pattern;
+     `used' to the length of the compiled pattern;
+     `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
+       REG_EXTENDED bit in CFLAGS is set; otherwise, to
+       RE_SYNTAX_POSIX_BASIC;
+     `newline_anchor' to REG_NEWLINE being set in CFLAGS;
+     `fastmap' to an allocated space for the fastmap;
+     `fastmap_accurate' to zero;
+     `re_nsub' to the number of subexpressions in PATTERN.
+
+   PATTERN is the address of the pattern string.
+
+   CFLAGS is a series of bits which affect compilation.
+
+     If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
+     use POSIX basic syntax.
+
+     If REG_NEWLINE is set, then . and [^...] don't match newline.
+     Also, regexec will try a match beginning after every newline.
+
+     If REG_ICASE is set, then we considers upper- and lowercase
+     versions of letters to be equivalent when matching.
+
+     If REG_NOSUB is set, then when PREG is passed to regexec, that
+     routine will report only success or failure, and nothing about the
+     registers.
+
+   It returns 0 if it succeeds, nonzero if it doesn't.  (See regex.h for
+   the return codes and their meanings.)  */
+
+int regcomp(preg, pattern, cflags)
+regex_t *preg;
+const char *pattern;
+int cflags;
+{
+	reg_errcode_t ret;
+	reg_syntax_t syntax
+		= (cflags & REG_EXTENDED) ?
+
+		RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
+
+	/* regex_compile will allocate the space for the compiled pattern.  */
+	preg->buffer = 0;
+	preg->allocated = 0;
+	preg->used = 0;
+
+	/* Try to allocate space for the fastmap.  */
+	preg->fastmap = (char *) malloc(1 << BYTEWIDTH);
+
+	if (cflags & REG_ICASE) {
+		unsigned i;
+
+		preg->translate
+			= (RE_TRANSLATE_TYPE) malloc(CHAR_SET_SIZE
+										 * sizeof(*(RE_TRANSLATE_TYPE) 0));
+		if (preg->translate == NULL)
+			return (int) REG_ESPACE;
+
+		/* Map uppercase characters to corresponding lowercase ones.  */
+		for (i = 0; i < CHAR_SET_SIZE; i++)
+			preg->translate[i] = ISUPPER(i) ? TOLOWER(i) : i;
+	} else
+		preg->translate = NULL;
+
+	/* If REG_NEWLINE is set, newlines are treated differently.  */
+	if (cflags & REG_NEWLINE) {	/* REG_NEWLINE implies neither . nor [^...] match newline.  */
+		syntax &= ~RE_DOT_NEWLINE;
+		syntax |= RE_HAT_LISTS_NOT_NEWLINE;
+		/* It also changes the matching behavior.  */
+		preg->newline_anchor = 1;
+	} else
+		preg->newline_anchor = 0;
+
+	preg->no_sub = !!(cflags & REG_NOSUB);
+
+	/* POSIX says a null character in the pattern terminates it, so we
+	   can use strlen here in compiling the pattern.  */
+	ret = regex_compile(pattern, strlen(pattern), syntax, preg);
+
+	/* POSIX doesn't distinguish between an unmatched open-group and an
+	   unmatched close-group: both are REG_EPAREN.  */
+	if (ret == REG_ERPAREN)
+		ret = REG_EPAREN;
+
+	if (ret == REG_NOERROR && preg->fastmap) {
+		/* Compute the fastmap now, since regexec cannot modify the pattern
+		   buffer.  */
+		if (re_compile_fastmap(preg) == -2) {
+			/* Some error occurred while computing the fastmap, just forget
+			   about it.  */
+			free(preg->fastmap);
+			preg->fastmap = NULL;
+		}
+	}
+
+	return (int) ret;
+}
+
+#ifdef _LIBC
+weak_alias(__regcomp, regcomp)
+#endif
+/* regexec searches for a given pattern, specified by PREG, in the
+   string STRING.
+
+   If NMATCH is zero or REG_NOSUB was set in the cflags argument to
+   `regcomp', we ignore PMATCH.  Otherwise, we assume PMATCH has at
+   least NMATCH elements, and we set them to the offsets of the
+   corresponding matched substrings.
+
+   EFLAGS specifies `execution flags' which affect matching: if
+   REG_NOTBOL is set, then ^ does not match at the beginning of the
+   string; if REG_NOTEOL is set, then $ does not match at the end.
+
+   We return 0 if we find a match and REG_NOMATCH if not.  */
+int regexec(preg, string, nmatch, pmatch, eflags)
+const regex_t *preg;
+const char *string;
+size_t nmatch;
+regmatch_t pmatch[];
+int eflags;
+{
+	int ret;
+	struct re_registers regs;
+	regex_t private_preg;
+	int len = strlen(string);
+	boolean want_reg_info = !preg->no_sub && nmatch > 0;
+
+	private_preg = *preg;
+
+	private_preg.not_bol = !!(eflags & REG_NOTBOL);
+	private_preg.not_eol = !!(eflags & REG_NOTEOL);
+
+	/* The user has told us exactly how many registers to return
+	   information about, via `nmatch'.  We have to pass that on to the
+	   matching routines.  */
+	private_preg.regs_allocated = REGS_FIXED;
+
+	if (want_reg_info) {
+		regs.num_regs = nmatch;
+		regs.start = TALLOC(nmatch * 2, regoff_t);
+		if (regs.start == NULL)
+			return (int) REG_NOMATCH;
+		regs.end = regs.start + nmatch;
+	}
+
+	/* Perform the searching operation.  */
+	ret = re_search(&private_preg, string, len,
+					/* start: */ 0, /* range: */ len,
+					want_reg_info ? &regs : (struct re_registers *) 0);
+
+	/* Copy the register information to the POSIX structure.  */
+	if (want_reg_info) {
+		if (ret >= 0) {
+			unsigned r;
+
+			for (r = 0; r < nmatch; r++) {
+				pmatch[r].rm_so = regs.start[r];
+				pmatch[r].rm_eo = regs.end[r];
+			}
+		}
+
+		/* If we needed the temporary register info, free the space now.  */
+		free(regs.start);
+	}
+
+	/* We want zero return to mean success, unlike `re_search'.  */
+	return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
+}
+
+#ifdef _LIBC
+weak_alias(__regexec, regexec)
+#endif
+/* Returns a message corresponding to an error code, ERRCODE, returned
+   from either regcomp or regexec.   We don't use PREG here.  */
+	size_t regerror(errcode, preg, errbuf, errbuf_size)
+int errcode;
+const regex_t *preg;
+char *errbuf;
+size_t errbuf_size;
+{
+	const char *msg;
+	size_t msg_size;
+
+	if (errcode < 0 || errcode >= (int) (sizeof(re_error_msgid_idx)
+										 / sizeof(re_error_msgid_idx[0])))
+		/* Only error codes returned by the rest of the code should be passed
+		   to this routine.  If we are given anything else, or if other regex
+		   code generates an invalid error code, then the program has a bug.
+		   Dump core so we can fix it.  */
+		abort();
+
+	msg = gettext(re_error_msgid + re_error_msgid_idx[errcode]);
+
+	msg_size = strlen(msg) + 1;	/* Includes the null.  */
+
+	if (errbuf_size != 0) {
+		if (msg_size > errbuf_size) {
+#if defined HAVE_MEMPCPY || defined _LIBC
+			*((char *) __mempcpy(errbuf, msg, errbuf_size - 1)) = '\0';
+#else
+			memcpy(errbuf, msg, errbuf_size - 1);
+			errbuf[errbuf_size - 1] = 0;
+#endif
+		} else
+			memcpy(errbuf, msg, msg_size);
+	}
+
+	return msg_size;
+}
+
+#ifdef _LIBC
+weak_alias(__regerror, regerror)
+#endif
+/* Free dynamically allocated space used by PREG.  */
+void regfree(preg)
+regex_t *preg;
+{
+	if (preg->buffer != NULL)
+		free(preg->buffer);
+	preg->buffer = NULL;
+
+	preg->allocated = 0;
+	preg->used = 0;
+
+	if (preg->fastmap != NULL)
+		free(preg->fastmap);
+	preg->fastmap = NULL;
+	preg->fastmap_accurate = 0;
+
+	if (preg->translate != NULL)
+		free(preg->translate);
+	preg->translate = NULL;
+}
+
+#ifdef _LIBC
+weak_alias(__regfree, regfree)
+#endif
+#endif							/* not emacs  */
diff --git a/libc/misc/regex/rx.c b/libc/misc/regex/rx.c
deleted file mode 100644
index 39f77adb6..000000000
--- a/libc/misc/regex/rx.c
+++ /dev/null
@@ -1,7273 +0,0 @@
-/*	Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
-
-This file is part of the librx library.
-
-Librx is free software; you can redistribute it and/or modify it under
-the terms of the GNU Library General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-Librx is distributed in the hope that it will be useful, but WITHOUT
-ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-for more details.
-
-You should have received a copy of the GNU Library General Public
-License along with this software; see the file COPYING.LIB.  If not,
-write to the Free Software Foundation, 675 Mass Ave, Cambridge, MA
-02139, USA.  */
-
-/* NOTE!!!  AIX is so losing it requires this to be the first thing in the 
- * file. 
- * Do not put ANYTHING before it!  
- */
-#if !defined (__GNUC__) && defined (_AIX)
-#pragma alloca
-#endif
-
-/* To make linux happy? */
-#ifndef	_GNU_SOURCE
-#define	_GNU_SOURCE
-#endif
-
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#ifndef isgraph
-#define isgraph(c) (isprint (c) && !isspace (c))
-#endif
-#ifndef isblank
-#define isblank(c) ((c) == ' ' || (c) == '\t')
-#endif
-
-#include <sys/types.h>
-
-#undef MAX
-#undef MIN
-#define MAX(a, b) ((a) > (b) ? (a) : (b))
-#define MIN(a, b) ((a) < (b) ? (a) : (b))
-
-typedef char boolean;
-
-#define false 0
-#define true 1
-
-#ifndef __GCC__
-#undef __inline__
-#define __inline__
-#endif
-
-/* Emacs already defines alloca, sometimes.  */
-#ifndef alloca
-
-/* Make alloca work the best possible way.  */
-#ifdef __GNUC__
-#define alloca __builtin_alloca
-#else							/* not __GNUC__ */
-#if HAVE_ALLOCA_H
-#include <alloca.h>
-#else							/* not __GNUC__ or HAVE_ALLOCA_H */
-#ifndef _AIX					/* Already did AIX, up at the top.  */
-char *alloca();
-#endif							/* not _AIX */
-#endif							/* not HAVE_ALLOCA_H */
-#endif							/* not __GNUC__ */
-
-#endif							/* not alloca */
-
-/* Memory management and stuff for emacs. */
-
-#define CHARBITS 8
-#define remalloc(M, S) (M ? realloc (M, S) : malloc (S))
-
-
-/* Should we use malloc or alloca?  If REGEX_MALLOC is not defined, we
- * use `alloca' instead of `malloc' for the backtracking stack.
- *
- * Emacs will die miserably if we don't do this.
- */
-
-#ifdef REGEX_MALLOC
-#define REGEX_ALLOCATE malloc
-#else							/* not REGEX_MALLOC  */
-#define REGEX_ALLOCATE alloca
-#endif							/* not REGEX_MALLOC */
-
-
-#ifdef RX_WANT_RX_DEFS
-#define RX_DECL extern
-#define RX_DEF_QUAL
-#else
-#define RX_WANT_RX_DEFS
-#define RX_DECL static
-#define RX_DEF_QUAL static
-#endif
-
-#include <regex.h>
-#undef RX_DECL
-#define RX_DECL RX_DEF_QUAL
-
-
-/*
- *  Prototypes.
- */
-#ifdef __STDC__
-RX_DECL struct rx_hash_item
-*rx_hash_find(struct rx_hash *, unsigned long,
-
-			  void *, struct rx_hash_rules *);
-RX_DECL struct rx_hash_item
-*rx_hash_find(struct rx_hash *, unsigned long,
-
-			  void *, struct rx_hash_rules *);
-RX_DECL struct rx_hash_item
-*rx_hash_store(struct rx_hash *, unsigned long,
-
-			   void *, struct rx_hash_rules *);
-RX_DECL void rx_hash_free(struct rx_hash_item *, struct rx_hash_rules *);
-RX_DECL void rx_free_hash_table(struct rx_hash *, rx_hash_freefn,
-
-								struct rx_hash_rules *);
-RX_DECL rx_Bitset rx_cset(struct rx *);
-RX_DECL rx_Bitset rx_copy_cset(struct rx *, rx_Bitset);
-RX_DECL void rx_free_cset(struct rx *, rx_Bitset);
-static struct rx_hash_item
-*compiler_hash_item_alloc(struct rx_hash_rules *, void *);
-static struct rx_hash
-*compiler_hash_alloc(struct rx_hash_rules *);
-static void compiler_free_hash(struct rx_hash *, struct rx_hash_rules *);
-static void compiler_free_hash_item(struct rx_hash_item *,
-
-									struct rx_hash_rules *);
-RX_DECL struct rexp_node
-*rexp_node(struct rx *, enum rexp_node_type);
-RX_DECL struct rexp_node
-*rx_mk_r_cset(struct rx *, rx_Bitset);
-RX_DECL struct rexp_node
-*rx_mk_r_concat(struct rx *, struct rexp_node *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_alternate(struct rx *, struct rexp_node *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_alternate(struct rx *, struct rexp_node *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_opt(struct rx *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_star(struct rx *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_2phase_star(struct rx *, struct rexp_node *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_mk_r_side_effect(struct rx *, rx_side_effect);
-
-//RX_DECL struct rexp_node
-//            *rx_mk_r_data              (struct rx *, void *);
-RX_DECL void rx_free_rexp(struct rx *, struct rexp_node *);
-RX_DECL struct rexp_node
-*rx_copy_rexp(struct rx *, struct rexp_node *);
-RX_DECL struct rx_nfa_state
-*rx_nfa_state(struct rx *);
-RX_DECL void rx_free_nfa_state(struct rx_nfa_state *);
-RX_DECL struct rx_nfa_state
-*rx_id_to_nfa_state(struct rx *, int);
-RX_DECL struct rx_nfa_edge
-*rx_nfa_edge(struct rx *, enum rx_nfa_etype,
-
-			 struct rx_nfa_state *, struct rx_nfa_state *);
-RX_DECL void rx_free_nfa_edge(struct rx_nfa_edge *);
-static struct rx_possible_future
-*rx_possible_future(struct rx *, struct rx_se_list *);
-static void rx_free_possible_future(struct rx_possible_future *);
-RX_DECL void rx_free_nfa(struct rx *);
-RX_DECL int rx_build_nfa(struct rx *, struct rexp_node *,
-						 struct rx_nfa_state **, struct rx_nfa_state **);
-RX_DECL void rx_name_nfa_states(struct rx *);
-static int se_list_cmp(void *, void *);
-static int se_list_equal(void *, void *);
-static struct rx_se_list
-*hash_cons_se_prog(struct rx *, struct rx_hash *,
-
-				   void *, struct rx_se_list *);
-static struct rx_se_list
-*hash_se_prog(struct rx *, struct rx_hash *, struct rx_se_list *);
-static int nfa_set_cmp(void *, void *);
-static int nfa_set_equal(void *, void *);
-static struct rx_nfa_state_set
-*nfa_set_cons(struct rx *, struct rx_hash *,
-
-			  struct rx_nfa_state *, struct rx_nfa_state_set *);
-static struct rx_nfa_state_set
-*nfa_set_enjoin(struct rx *, struct rx_hash *,
-
-				struct rx_nfa_state *, struct rx_nfa_state_set *);
-#endif
-
-#ifndef emacs
-
-#ifdef SYNTAX_TABLE
-extern char *re_syntax_table;
-#else							/* not SYNTAX_TABLE */
-
-#ifndef RX_WANT_RX_DEFS
-RX_DECL char re_syntax_table[CHAR_SET_SIZE];
-#endif
-
-#ifdef __STDC__
-static void init_syntax_once(void)
-#else
-static void init_syntax_once()
-#endif
-{
-	register int c;
-	static int done = 0;
-
-	if (done)
-		return;
-
-	bzero(re_syntax_table, sizeof re_syntax_table);
-
-	for (c = 'a'; c <= 'z'; c++)
-		re_syntax_table[c] = Sword;
-
-	for (c = 'A'; c <= 'Z'; c++)
-		re_syntax_table[c] = Sword;
-
-	for (c = '0'; c <= '9'; c++)
-		re_syntax_table[c] = Sword;
-
-	re_syntax_table['_'] = Sword;
-
-	done = 1;
-}
-#endif							/* not SYNTAX_TABLE */
-#endif							/* not emacs */
-
-/* Compile with `-DRX_DEBUG' and use the following flags.
- *
- * Debugging flags:
- *   	rx_debug - print information as a regexp is compiled
- * 	rx_debug_trace - print information as a regexp is executed
- */
-
-#ifdef RX_DEBUG
-
-int rx_debug_compile = 0;
-int rx_debug_trace = 0;
-static struct re_pattern_buffer *dbug_rxb = 0;
-
-
-/*
- * More Prototypes
- */
-#ifdef __STDC__
-typedef void (*side_effect_printer) (struct rx *, void *, FILE *);
-static void print_cset(struct rx *, rx_Bitset, FILE *);
-static void print_rexp(struct rx *, struct rexp_node *, int,
-					   side_effect_printer, FILE *);
-static void print_nfa(struct rx *, struct rx_nfa_state *,
-					  side_effect_printer, FILE *);
-static void re_seprint(struct rx *, void *, FILE *);
-void print_compiled_pattern(struct re_pattern_buffer *);
-void print_fastmap(char *);
-#else
-typedef void (*side_effect_printer) ();
-static void print_cset();
-#endif
-
-#ifdef __STDC__
-static void
-print_rexp(struct rx *rx,
-		   struct rexp_node *node, int depth,
-		   side_effect_printer seprint, FILE * fp)
-#else
-static void print_rexp(rx, node, depth, seprint, fp)
-struct rx *rx;
-struct rexp_node *node;
-int depth;
-side_effect_printer seprint;
-FILE *fp;
-#endif
-{
-	if (!node)
-		return;
-	else {
-		switch (node->type) {
-		case r_cset:
-		{
-			fprintf(fp, "%*s", depth, "");
-			print_cset(rx, node->params.cset, fp);
-			fputc('\n', fp);
-			break;
-		}
-
-		case r_opt:
-		case r_star:
-			fprintf(fp, "%*s%s\n", depth, "",
-					node->type == r_opt ? "opt" : "star");
-			print_rexp(rx, node->params.pair.left, depth + 3, seprint, fp);
-			break;
-
-		case r_2phase_star:
-			fprintf(fp, "%*s2phase star\n", depth, "");
-			print_rexp(rx, node->params.pair.right, depth + 3, seprint,
-					   fp);
-			print_rexp(rx, node->params.pair.left, depth + 3, seprint, fp);
-			break;
-
-
-		case r_alternate:
-		case r_concat:
-			fprintf(fp, "%*s%s\n", depth, "",
-					node->type == r_alternate ? "alt" : "concat");
-			print_rexp(rx, node->params.pair.left, depth + 3, seprint, fp);
-			print_rexp(rx, node->params.pair.right, depth + 3, seprint,
-					   fp);
-			break;
-		case r_side_effect:
-			fprintf(fp, "%*sSide effect: ", depth, "");
-			seprint(rx, node->params.side_effect, fp);
-			fputc('\n', fp);
-		}
-	}
-}
-
-#ifdef __STDC__
-static void
-print_nfa(struct rx *rx,
-		  struct rx_nfa_state *n, side_effect_printer seprint, FILE * fp)
-#else
-static void print_nfa(rx, n, seprint, fp)
-struct rx *rx;
-struct rx_nfa_state *n;
-side_effect_printer seprint;
-FILE *fp;
-#endif
-{
-	while (n) {
-		struct rx_nfa_edge *e = n->edges;
-		struct rx_possible_future *ec = n->futures;
-
-		fprintf(fp, "node %d %s\n", n->id,
-				n->is_final ? "final" : (n->is_start ? "start" : ""));
-		while (e) {
-			fprintf(fp, "   edge to %d, ", e->dest->id);
-			switch (e->type) {
-			case ne_epsilon:
-				fprintf(fp, "epsilon\n");
-				break;
-			case ne_side_effect:
-				fprintf(fp, "side effect ");
-				seprint(rx, e->params.side_effect, fp);
-				fputc('\n', fp);
-				break;
-			case ne_cset:
-				fprintf(fp, "cset ");
-				print_cset(rx, e->params.cset, fp);
-				fputc('\n', fp);
-				break;
-			}
-			e = e->next;
-		}
-
-		while (ec) {
-			int x;
-			struct rx_nfa_state_set *s;
-			struct rx_se_list *l;
-
-			fprintf(fp, "   eclosure to {");
-			for (s = ec->destset; s; s = s->cdr)
-				fprintf(fp, "%d ", s->car->id);
-			fprintf(fp, "} (");
-			for (l = ec->effects; l; l = l->cdr) {
-				seprint(rx, l->car, fp);
-				fputc(' ', fp);
-			}
-			fprintf(fp, ")\n");
-			ec = ec->next;
-		}
-		n = n->next;
-	}
-}
-
-static char *efnames[] = {
-	"bogon",
-	"re_se_try",
-	"re_se_pushback",
-	"re_se_push0",
-	"re_se_pushpos",
-	"re_se_chkpos",
-	"re_se_poppos",
-	"re_se_at_dot",
-	"re_se_syntax",
-	"re_se_not_syntax",
-	"re_se_begbuf",
-	"re_se_hat",
-	"re_se_wordbeg",
-	"re_se_wordbound",
-	"re_se_notwordbound",
-	"re_se_wordend",
-	"re_se_endbuf",
-	"re_se_dollar",
-	"re_se_fail",
-};
-
-static char *efnames2[] = {
-	"re_se_win",
-	"re_se_lparen",
-	"re_se_rparen",
-	"re_se_backref",
-	"re_se_iter",
-	"re_se_end_iter",
-	"re_se_tv"
-};
-
-static char *inx_names[] = {
-	"rx_backtrack_point",
-	"rx_do_side_effects",
-	"rx_cache_miss",
-	"rx_next_char",
-	"rx_backtrack",
-	"rx_error_inx",
-	"rx_num_instructions"
-};
-
-
-#ifdef __STDC__
-static void re_seprint(struct rx *rx, void *effect, FILE * fp)
-#else
-static void re_seprint(rx, effect, fp)
-struct rx *rx;
-void *effect;
-FILE *fp;
-#endif
-{
-	if ((int) effect < 0)
-		fputs(efnames[-(int) effect], fp);
-	else if (dbug_rxb) {
-		struct re_se_params *p = &dbug_rxb->se_params[(int) effect];
-
-		fprintf(fp, "%s(%d,%d)", efnames2[p->se], p->op1, p->op2);
-	} else
-		fprintf(fp, "[complex op # %d]", (int) effect);
-}
-
-/* These are so the regex.c regression tests will compile. */
-void print_compiled_pattern(rxb)
-struct re_pattern_buffer *rxb;
-{
-}
-
-void print_fastmap(fm)
-char *fm;
-{
-}
-
-#endif							/* RX_DEBUG */
-
-
-
-/* This page: Bitsets.  Completely unintersting. */
-
-//RX_DECL int   rx_bitset_is_equal        (int, rx_Bitset, rx_Bitset);
-RX_DECL int rx_bitset_is_subset(int, rx_Bitset, rx_Bitset);
-
-//RX_DECL int   rx_bitset_empty           (int, rx_Bitset);
-RX_DECL void rx_bitset_null(int, rx_Bitset);
-RX_DECL void rx_bitset_complement(int, rx_Bitset);
-RX_DECL void rx_bitset_complement(int, rx_Bitset);
-RX_DECL void rx_bitset_assign(int, rx_Bitset, rx_Bitset);
-RX_DECL void rx_bitset_union(int, rx_Bitset, rx_Bitset);
-RX_DECL void rx_bitset_intersection(int, rx_Bitset, rx_Bitset);
-RX_DECL void rx_bitset_difference(int, rx_Bitset, rx_Bitset);
-
-//RX_DECL void  rx_bitset_revdifference   (int, rx_Bitset, rx_Bitset);
-#ifdef emacs
-RX_DECL void rx_bitset_xor(int, rx_Bitset, rx_Bitset);
-#endif
-RX_DECL unsigned long rx_bitset_hash(int, rx_Bitset);
-
-#if 0
-#ifdef __STDC__
-RX_DECL int rx_bitset_is_equal(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL int rx_bitset_is_equal(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-	RX_subset s = b[0];
-
-	b[0] = ~a[0];
-
-	for (x = rx_bitset_numb_subsets(size) - 1; a[x] == b[x]; --x);
-
-	b[0] = s;
-	return !x && s == a[0];
-}
-#endif
-
-#ifdef __STDC__
-RX_DECL int rx_bitset_is_subset(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL int rx_bitset_is_subset(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x = rx_bitset_numb_subsets(size) - 1;
-
-	while (x-- && (a[x] & b[x]) == a[x]);
-	return x == -1;
-}
-
-#if 0
-#ifdef __STDC__
-RX_DECL int rx_bitset_empty(int size, rx_Bitset set)
-#else
-RX_DECL int rx_bitset_empty(size, set)
-int size;
-rx_Bitset set;
-#endif
-{
-	int x;
-	RX_subset s = set[0];
-
-	set[0] = 1;
-	for (x = rx_bitset_numb_subsets(size) - 1; !set[x]; --x);
-	set[0] = s;
-	return !s;
-}
-#endif
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_null(int size, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_null(size, b)
-int size;
-rx_Bitset b;
-#endif
-{
-	bzero(b, rx_sizeof_bitset(size));
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_universe(int size, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_universe(size, b)
-int size;
-rx_Bitset b;
-#endif
-{
-	int x = rx_bitset_numb_subsets(size);
-
-	while (x--)
-		*b++ = ~(RX_subset) 0;
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_complement(int size, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_complement(size, b)
-int size;
-rx_Bitset b;
-#endif
-{
-	int x = rx_bitset_numb_subsets(size);
-
-	while (x--) {
-		*b = ~*b;
-		++b;
-	}
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_assign(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_assign(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] = b[x];
-}
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_union(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_union(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] |= b[x];
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_intersection(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_intersection(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] &= b[x];
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_bitset_difference(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_difference(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] &= ~b[x];
-}
-
-
-#if 0
-#ifdef __STDC__
-RX_DECL void rx_bitset_revdifference(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_revdifference(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] = ~a[x] & b[x];
-}
-#endif
-
-
-#ifdef emacs
-#ifdef __STDC__
-RX_DECL void rx_bitset_xor(int size, rx_Bitset a, rx_Bitset b)
-#else
-RX_DECL void rx_bitset_xor(size, a, b)
-int size;
-rx_Bitset a;
-rx_Bitset b;
-#endif
-{
-	int x;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		a[x] ^= b[x];
-}
-#endif
-
-
-#ifdef __STDC__
-RX_DECL unsigned long rx_bitset_hash(int size, rx_Bitset b)
-#else
-RX_DECL unsigned long rx_bitset_hash(size, b)
-int size;
-rx_Bitset b;
-#endif
-{
-	int x;
-	unsigned long hash = (unsigned long) rx_bitset_hash;
-
-	for (x = rx_bitset_numb_subsets(size) - 1; x >= 0; --x)
-		hash ^= rx_bitset_subset_val(b, x);
-
-	return hash;
-}
-
-RX_DECL RX_subset rx_subset_singletons[RX_subset_bits] = {
-	0x1,
-	0x2,
-	0x4,
-	0x8,
-	0x10,
-	0x20,
-	0x40,
-	0x80,
-	0x100,
-	0x200,
-	0x400,
-	0x800,
-	0x1000,
-	0x2000,
-	0x4000,
-	0x8000,
-	0x10000,
-	0x20000,
-	0x40000,
-	0x80000,
-	0x100000,
-	0x200000,
-	0x400000,
-	0x800000,
-	0x1000000,
-	0x2000000,
-	0x4000000,
-	0x8000000,
-	0x10000000,
-	0x20000000,
-	0x40000000,
-	0x80000000
-};
-
-#ifdef RX_DEBUG
-
-#ifdef __STDC__
-static void print_cset(struct rx *rx, rx_Bitset cset, FILE * fp)
-#else
-static void print_cset(rx, cset, fp)
-struct rx *rx;
-rx_Bitset cset;
-FILE *fp;
-#endif
-{
-	int x;
-
-	fputc('[', fp);
-	for (x = 0; x < rx->local_cset_size; ++x)
-		if (RX_bitset_member(cset, x)) {
-			if (isprint(x))
-				fputc(x, fp);
-			else
-				fprintf(fp, "\\0%o ", x);
-		}
-	fputc(']', fp);
-}
-
-#endif							/*  RX_DEBUG */
-
-
-
-static unsigned long rx_hash_masks[4] = {
-	0x12488421,
-	0x96699669,
-	0xbe7dd7eb,
-	0xffffffff
-};
-
-
-/* Hash tables */
-#ifdef __STDC__
-RX_DECL struct rx_hash_item *rx_hash_find(struct rx_hash *table,
-										  unsigned long hash,
-										  void *value,
-										  struct rx_hash_rules *rules)
-#else
-RX_DECL struct rx_hash_item *rx_hash_find(table, hash, value, rules)
-struct rx_hash *table;
-unsigned long hash;
-void *value;
-struct rx_hash_rules *rules;
-#endif
-{
-	rx_hash_eq eq = rules->eq;
-	int maskc = 0;
-	long mask = rx_hash_masks[0];
-	int bucket = (hash & mask) % 13;
-
-	while (table->children[bucket]) {
-		table = table->children[bucket];
-		++maskc;
-		mask = rx_hash_masks[maskc];
-		bucket = (hash & mask) % 13;
-	}
-
-	{
-		struct rx_hash_item *it = table->buckets[bucket];
-
-		while (it)
-			if (eq(it->data, value))
-				return it;
-			else
-				it = it->next_same_hash;
-	}
-
-	return 0;
-}
-
-#ifdef __STDC__
-RX_DECL struct rx_hash_item *rx_hash_store(struct rx_hash *table,
-										   unsigned long hash,
-										   void *value,
-										   struct rx_hash_rules *rules)
-#else
-RX_DECL struct rx_hash_item *rx_hash_store(table, hash, value, rules)
-struct rx_hash *table;
-unsigned long hash;
-void *value;
-struct rx_hash_rules *rules;
-#endif
-{
-	rx_hash_eq eq = rules->eq;
-	int maskc = 0;
-	long mask = rx_hash_masks[0];
-	int bucket = (hash & mask) % 13;
-	int depth = 0;
-
-	while (table->children[bucket]) {
-		table = table->children[bucket];
-		++maskc;
-		mask = rx_hash_masks[maskc];
-		bucket = (hash & mask) % 13;
-		++depth;
-	}
-
-	{
-		struct rx_hash_item *it = table->buckets[bucket];
-
-		while (it)
-			if (eq(it->data, value))
-				return it;
-			else
-				it = it->next_same_hash;
-	}
-
-	{
-		if ((depth < 3)
-			&& (table->bucket_size[bucket] >= 4)) {
-			struct rx_hash *newtab = ((struct rx_hash *)
-									   rules->hash_alloc(rules));
-
-			if (!newtab)
-				goto add_to_bucket;
-			bzero(newtab, sizeof(*newtab));
-			newtab->parent = table;
-			{
-				struct rx_hash_item *them = table->buckets[bucket];
-				unsigned long newmask = rx_hash_masks[maskc + 1];
-
-				while (them) {
-					struct rx_hash_item *save = them->next_same_hash;
-					int new_buck = (them->hash & newmask) % 13;
-
-					them->next_same_hash = newtab->buckets[new_buck];
-					newtab->buckets[new_buck] = them;
-					them->table = newtab;
-					them = save;
-					++newtab->bucket_size[new_buck];
-					++newtab->refs;
-				}
-				table->refs =
-					(table->refs - table->bucket_size[bucket] + 1);
-				table->bucket_size[bucket] = 0;
-				table->buckets[bucket] = 0;
-				table->children[bucket] = newtab;
-				table = newtab;
-				bucket = (hash & newmask) % 13;
-			}
-		}
-	}
-  add_to_bucket:
-	{
-		struct rx_hash_item *it = ((struct rx_hash_item *)
-								   rules->hash_item_alloc(rules, value));
-
-		if (!it)
-			return 0;
-		it->hash = hash;
-		it->table = table;
-		/* DATA and BINDING are to be set in hash_item_alloc */
-		it->next_same_hash = table->buckets[bucket];
-		table->buckets[bucket] = it;
-		++table->bucket_size[bucket];
-		++table->refs;
-		return it;
-	}
-}
-
-
-#ifdef __STDC__
-RX_DECL void
-rx_hash_free(struct rx_hash_item *it, struct rx_hash_rules *rules)
-#else
-RX_DECL void rx_hash_free(it, rules)
-struct rx_hash_item *it;
-struct rx_hash_rules *rules;
-#endif
-{
-	if (it) {
-		struct rx_hash *table = it->table;
-		unsigned long hash = it->hash;
-		int depth = (table->parent
-					 ? (table->parent->parent
-						? (table->parent->parent->parent ? 3 : 2)
-						: 1)
-					 : 0);
-		int bucket = (hash & rx_hash_masks[depth]) % 13;
-		struct rx_hash_item **pos = &table->buckets[bucket];
-
-		while (*pos != it)
-			pos = &(*pos)->next_same_hash;
-		*pos = it->next_same_hash;
-		rules->free_hash_item(it, rules);
-		--table->bucket_size[bucket];
-		--table->refs;
-		while (!table->refs && depth) {
-			struct rx_hash *save = table;
-
-			table = table->parent;
-			--depth;
-			bucket = (hash & rx_hash_masks[depth]) % 13;
-			--table->refs;
-			table->children[bucket] = 0;
-			rules->free_hash(save, rules);
-		}
-	}
-}
-
-#ifdef __STDC__
-RX_DECL void
-rx_free_hash_table(struct rx_hash *tab, rx_hash_freefn freefn,
-				   struct rx_hash_rules *rules)
-#else
-RX_DECL void rx_free_hash_table(tab, freefn, rules)
-struct rx_hash *tab;
-rx_hash_freefn freefn;
-struct rx_hash_rules *rules;
-#endif
-{
-	int x;
-
-	for (x = 0; x < 13; ++x)
-		if (tab->children[x]) {
-			rx_free_hash_table(tab->children[x], freefn, rules);
-			rules->free_hash(tab->children[x], rules);
-		} else {
-			struct rx_hash_item *them = tab->buckets[x];
-
-			while (them) {
-				struct rx_hash_item *that = them;
-
-				them = that->next_same_hash;
-				freefn(that);
-				rules->free_hash_item(that, rules);
-			}
-		}
-}
-
-
-
-/* Utilities for manipulating bitset represntations of characters sets. */
-
-#ifdef __STDC__
-RX_DECL rx_Bitset rx_cset(struct rx *rx)
-#else
-RX_DECL rx_Bitset rx_cset(rx)
-struct rx *rx;
-#endif
-{
-	rx_Bitset b =
-
-		(rx_Bitset) malloc(rx_sizeof_bitset(rx->local_cset_size));
-	if (b)
-		rx_bitset_null(rx->local_cset_size, b);
-	return b;
-}
-
-
-#ifdef __STDC__
-RX_DECL rx_Bitset rx_copy_cset(struct rx * rx, rx_Bitset a)
-#else
-RX_DECL rx_Bitset rx_copy_cset(rx, a)
-struct rx *rx;
-rx_Bitset a;
-#endif
-{
-	rx_Bitset cs = rx_cset(rx);
-
-	if (cs)
-		rx_bitset_union(rx->local_cset_size, cs, a);
-
-	return cs;
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_free_cset(struct rx *rx, rx_Bitset c)
-#else
-RX_DECL void rx_free_cset(rx, c)
-struct rx *rx;
-rx_Bitset c;
-#endif
-{
-	if (c)
-		free((char *) c);
-}
-
-
-/* Hash table memory allocation policy for the regexp compiler */
-
-#ifdef __STDC__
-static struct rx_hash *compiler_hash_alloc(struct rx_hash_rules *rules)
-#else
-static struct rx_hash *compiler_hash_alloc(rules)
-struct rx_hash_rules *rules;
-#endif
-{
-	return (struct rx_hash *) malloc(sizeof(struct rx_hash));
-}
-
-
-#ifdef __STDC__
-static struct rx_hash_item *compiler_hash_item_alloc(struct rx_hash_rules
-													 *rules, void *value)
-#else
-static struct rx_hash_item *compiler_hash_item_alloc(rules, value)
-struct rx_hash_rules *rules;
-void *value;
-#endif
-{
-	struct rx_hash_item *it;
-
-	it = (struct rx_hash_item *) malloc(sizeof(*it));
-	if (it) {
-		it->data = value;
-		it->binding = 0;
-	}
-	return it;
-}
-
-#ifdef __STDC__
-static void
-compiler_free_hash(struct rx_hash *tab, struct rx_hash_rules *rules)
-#else
-static void compiler_free_hash(tab, rules)
-struct rx_hash *tab;
-struct rx_hash_rules *rules;
-#endif
-{
-	free((char *) tab);
-}
-
-
-#ifdef __STDC__
-static void
-compiler_free_hash_item(struct rx_hash_item *item,
-						struct rx_hash_rules *rules)
-#else
-static void compiler_free_hash_item(item, rules)
-struct rx_hash_item *item;
-struct rx_hash_rules *rules;
-#endif
-{
-	free((char *) item);
-}
-
-
-/* This page: REXP_NODE (expression tree) structures. */
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rexp_node(struct rx *rx,
-									enum rexp_node_type type)
-#else
-RX_DECL struct rexp_node *rexp_node(rx, type)
-struct rx *rx;
-enum rexp_node_type type;
-#endif
-{
-	struct rexp_node *n;
-
-	n = (struct rexp_node *) malloc(sizeof(*n));
-	if (n) {
-		bzero(n, sizeof(*n));
-		n->type = type;
-	}
-	return n;
-}
-
-
-/* free_rexp_node assumes that the bitset passed to rx_mk_r_cset
- * can be freed using rx_free_cset.
- */
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_cset(struct rx *rx, rx_Bitset b)
-#else
-RX_DECL struct rexp_node *rx_mk_r_cset(rx, b)
-struct rx *rx;
-rx_Bitset b;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_cset);
-
-	if (n)
-		n->params.cset = b;
-	return n;
-}
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_concat(struct rx *rx,
-										 struct rexp_node *a,
-										 struct rexp_node *b)
-#else
-RX_DECL struct rexp_node *rx_mk_r_concat(rx, a, b)
-struct rx *rx;
-struct rexp_node *a;
-struct rexp_node *b;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_concat);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = b;
-	}
-	return n;
-}
-
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_alternate(struct rx *rx,
-											struct rexp_node *a,
-											struct rexp_node *b)
-#else
-RX_DECL struct rexp_node *rx_mk_r_alternate(rx, a, b)
-struct rx *rx;
-struct rexp_node *a;
-struct rexp_node *b;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_alternate);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = b;
-	}
-	return n;
-}
-
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_opt(struct rx *rx, struct rexp_node *a)
-#else
-RX_DECL struct rexp_node *rx_mk_r_opt(rx, a)
-struct rx *rx;
-struct rexp_node *a;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_opt);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = 0;
-	}
-	return n;
-}
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_star(struct rx *rx, struct rexp_node *a)
-#else
-RX_DECL struct rexp_node *rx_mk_r_star(rx, a)
-struct rx *rx;
-struct rexp_node *a;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_star);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = 0;
-	}
-	return n;
-}
-
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_2phase_star(struct rx *rx,
-											  struct rexp_node *a,
-											  struct rexp_node *b)
-#else
-RX_DECL struct rexp_node *rx_mk_r_2phase_star(rx, a, b)
-struct rx *rx;
-struct rexp_node *a;
-struct rexp_node *b;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_2phase_star);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = b;
-	}
-	return n;
-}
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_side_effect(struct rx *rx,
-											  rx_side_effect a)
-#else
-RX_DECL struct rexp_node *rx_mk_r_side_effect(rx, a)
-struct rx *rx;
-rx_side_effect a;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_side_effect);
-
-	if (n) {
-		n->params.side_effect = a;
-		n->params.pair.right = 0;
-	}
-	return n;
-}
-
-
-#if 0
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_mk_r_data(struct rx *rx, void *a)
-#else
-RX_DECL struct rexp_node *rx_mk_r_data(rx, a)
-struct rx *rx;
-void *a;
-#endif
-{
-	struct rexp_node *n = rexp_node(rx, r_data);
-
-	if (n) {
-		n->params.pair.left = a;
-		n->params.pair.right = 0;
-	}
-	return n;
-}
-#endif
-
-#ifdef __STDC__
-RX_DECL void rx_free_rexp(struct rx *rx, struct rexp_node *node)
-#else
-RX_DECL void rx_free_rexp(rx, node)
-struct rx *rx;
-struct rexp_node *node;
-#endif
-{
-	if (node) {
-		switch (node->type) {
-		case r_cset:
-			if (node->params.cset)
-				rx_free_cset(rx, node->params.cset);
-
-		case r_side_effect:
-			break;
-
-		case r_concat:
-		case r_alternate:
-		case r_2phase_star:
-		case r_opt:
-		case r_star:
-			rx_free_rexp(rx, node->params.pair.left);
-			rx_free_rexp(rx, node->params.pair.right);
-			break;
-
-		case r_data:
-			/* This shouldn't occur. */
-			break;
-		}
-		free((char *) node);
-	}
-}
-
-#ifdef __STDC__
-RX_DECL struct rexp_node *rx_copy_rexp(struct rx *rx,
-									   struct rexp_node *node)
-#else
-RX_DECL struct rexp_node *rx_copy_rexp(rx, node)
-struct rx *rx;
-struct rexp_node *node;
-#endif
-{
-	if (!node)
-		return 0;
-	else {
-		struct rexp_node *n = rexp_node(rx, node->type);
-
-		if (!n)
-			return 0;
-		switch (node->type) {
-		case r_cset:
-			n->params.cset = rx_copy_cset(rx, node->params.cset);
-			if (!n->params.cset) {
-				rx_free_rexp(rx, n);
-				return 0;
-			}
-			break;
-
-		case r_side_effect:
-			n->params.side_effect = node->params.side_effect;
-			break;
-
-		case r_concat:
-		case r_alternate:
-		case r_opt:
-		case r_2phase_star:
-		case r_star:
-			n->params.pair.left = rx_copy_rexp(rx, node->params.pair.left);
-			n->params.pair.right =
-				rx_copy_rexp(rx, node->params.pair.right);
-			if ((node->params.pair.left && !n->params.pair.left)
-				|| (node->params.pair.right && !n->params.pair.right)) {
-				rx_free_rexp(rx, n);
-				return 0;
-			}
-			break;
-		case r_data:
-			/* shouldn't happen */
-			break;
-		}
-		return n;
-	}
-}
-
-
-
-/* This page: functions to build and destroy graphs that describe nfa's */
-
-/* Constructs a new nfa node. */
-#ifdef __STDC__
-RX_DECL struct rx_nfa_state *rx_nfa_state(struct rx *rx)
-#else
-RX_DECL struct rx_nfa_state *rx_nfa_state(rx)
-struct rx *rx;
-#endif
-{
-	struct rx_nfa_state *n = (struct rx_nfa_state *) malloc(sizeof(*n));
-
-	if (!n)
-		return 0;
-	bzero(n, sizeof(*n));
-	n->next = rx->nfa_states;
-	rx->nfa_states = n;
-	return n;
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_free_nfa_state(struct rx_nfa_state *n)
-#else
-RX_DECL void rx_free_nfa_state(n)
-struct rx_nfa_state *n;
-#endif
-{
-	free((char *) n);
-}
-
-
-/* This looks up an nfa node, given a numeric id.  Numeric id's are
- * assigned after the nfa has been built.
- */
-#ifdef __STDC__
-RX_DECL struct rx_nfa_state *rx_id_to_nfa_state(struct rx *rx, int id)
-#else
-RX_DECL struct rx_nfa_state *rx_id_to_nfa_state(rx, id)
-struct rx *rx;
-int id;
-#endif
-{
-	struct rx_nfa_state *n;
-
-	for (n = rx->nfa_states; n; n = n->next)
-		if (n->id == id)
-			return n;
-	return 0;
-}
-
-
-/* This adds an edge between two nodes, but doesn't initialize the 
- * edge label.
- */
-
-#ifdef __STDC__
-RX_DECL struct rx_nfa_edge *rx_nfa_edge(struct rx *rx,
-										enum rx_nfa_etype type,
-										struct rx_nfa_state *start,
-										struct rx_nfa_state *dest)
-#else
-RX_DECL struct rx_nfa_edge *rx_nfa_edge(rx, type, start, dest)
-struct rx *rx;
-enum rx_nfa_etype type;
-struct rx_nfa_state *start;
-struct rx_nfa_state *dest;
-#endif
-{
-	struct rx_nfa_edge *e;
-
-	e = (struct rx_nfa_edge *) malloc(sizeof(*e));
-	if (!e)
-		return 0;
-	e->next = start->edges;
-	start->edges = e;
-	e->type = type;
-	e->dest = dest;
-	return e;
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_free_nfa_edge(struct rx_nfa_edge *e)
-#else
-RX_DECL void rx_free_nfa_edge(e)
-struct rx_nfa_edge *e;
-#endif
-{
-	free((char *) e);
-}
-
-
-/* This constructs a POSSIBLE_FUTURE, which is a kind epsilon-closure
- * of an NFA.  These are added to an nfa automaticly by eclose_nfa.
- */
-
-#ifdef __STDC__
-static struct rx_possible_future *rx_possible_future(struct rx *rx, struct rx_se_list
-													 *effects)
-#else
-static struct rx_possible_future *rx_possible_future(rx, effects)
-struct rx *rx;
-struct rx_se_list *effects;
-#endif
-{
-	struct rx_possible_future *ec;
-
-	ec = (struct rx_possible_future *) malloc(sizeof(*ec));
-	if (!ec)
-		return 0;
-	ec->destset = 0;
-	ec->next = 0;
-	ec->effects = effects;
-	return ec;
-}
-
-
-#ifdef __STDC__
-static void rx_free_possible_future(struct rx_possible_future *pf)
-#else
-static void rx_free_possible_future(pf)
-struct rx_possible_future *pf;
-#endif
-{
-	free((char *) pf);
-}
-
-
-#ifdef __STDC__
-RX_DECL void rx_free_nfa(struct rx *rx)
-#else
-RX_DECL void rx_free_nfa(rx)
-struct rx *rx;
-#endif
-{
-	while (rx->nfa_states) {
-		while (rx->nfa_states->edges) {
-			switch (rx->nfa_states->edges->type) {
-			case ne_cset:
-				rx_free_cset(rx, rx->nfa_states->edges->params.cset);
-				break;
-			default:
-				break;
-			}
-			{
-				struct rx_nfa_edge *e;
-
-				e = rx->nfa_states->edges;
-				rx->nfa_states->edges = rx->nfa_states->edges->next;
-				rx_free_nfa_edge(e);
-			}
-		}						/* while (rx->nfa_states->edges) */
-		{
-			/* Iterate over the partial epsilon closures of rx->nfa_states */
-			struct rx_possible_future *pf = rx->nfa_states->futures;
-
-			while (pf) {
-				struct rx_possible_future *pft = pf;
-
-				pf = pf->next;
-				rx_free_possible_future(pft);
-			}
-		}
-		{
-			struct rx_nfa_state *n;
-
-			n = rx->nfa_states;
-			rx->nfa_states = rx->nfa_states->next;
-			rx_free_nfa_state(n);
-		}
-	}
-}
-
-
-
-/* This page: translating a pattern expression into an nfa and doing the 
- * static part of the nfa->super-nfa translation.
- */
-
-/* This is the thompson regexp->nfa algorithm. 
- * It is modified to allow for `side-effect epsilons.'  Those are
- * edges that are taken whenever a similar epsilon edge would be,
- * but which imply that some side effect occurs when the edge 
- * is taken.
- *
- * Side effects are used to model parts of the pattern langauge 
- * that are not regular (in the formal sense).
- */
-
-#ifdef __STDC__
-RX_DECL int
-rx_build_nfa(struct rx *rx,
-			 struct rexp_node *rexp,
-			 struct rx_nfa_state **start, struct rx_nfa_state **end)
-#else
-RX_DECL int rx_build_nfa(rx, rexp, start, end)
-struct rx *rx;
-struct rexp_node *rexp;
-struct rx_nfa_state **start;
-struct rx_nfa_state **end;
-#endif
-{
-	struct rx_nfa_edge *edge;
-
-	/* Start & end nodes may have been allocated by the caller. */
-	*start = *start ? *start : rx_nfa_state(rx);
-
-	if (!*start)
-		return 0;
-
-	if (!rexp) {
-		*end = *start;
-		return 1;
-	}
-
-	*end = *end ? *end : rx_nfa_state(rx);
-
-	if (!*end) {
-		rx_free_nfa_state(*start);
-		return 0;
-	}
-
-	switch (rexp->type) {
-	case r_data:
-		return 0;
-
-	case r_cset:
-		edge = rx_nfa_edge(rx, ne_cset, *start, *end);
-		if (!edge)
-			return 0;
-		edge->params.cset = rx_copy_cset(rx, rexp->params.cset);
-		if (!edge->params.cset) {
-			rx_free_nfa_edge(edge);
-			return 0;
-		}
-		return 1;
-
-	case r_opt:
-		return (rx_build_nfa(rx, rexp->params.pair.left, start, end)
-				&& rx_nfa_edge(rx, ne_epsilon, *start, *end));
-
-	case r_star:
-	{
-		struct rx_nfa_state *star_start = 0;
-		struct rx_nfa_state *star_end = 0;
-
-		return (rx_build_nfa(rx, rexp->params.pair.left,
-							 &star_start, &star_end)
-				&& star_start
-				&& star_end
-				&& rx_nfa_edge(rx, ne_epsilon, star_start, star_end)
-				&& rx_nfa_edge(rx, ne_epsilon, *start, star_start)
-				&& rx_nfa_edge(rx, ne_epsilon, star_end, *end)
-
-				&& rx_nfa_edge(rx, ne_epsilon, star_end, star_start));
-	}
-
-	case r_2phase_star:
-	{
-		struct rx_nfa_state *star_start = 0;
-		struct rx_nfa_state *star_end = 0;
-		struct rx_nfa_state *loop_exp_start = 0;
-		struct rx_nfa_state *loop_exp_end = 0;
-
-		return (rx_build_nfa(rx, rexp->params.pair.left,
-							 &star_start, &star_end)
-				&& rx_build_nfa(rx, rexp->params.pair.right,
-								&loop_exp_start, &loop_exp_end)
-				&& star_start
-				&& star_end
-				&& loop_exp_end
-				&& loop_exp_start
-				&& rx_nfa_edge(rx, ne_epsilon, star_start, *end)
-				&& rx_nfa_edge(rx, ne_epsilon, *start, star_start)
-				&& rx_nfa_edge(rx, ne_epsilon, star_end, *end)
-
-				&& rx_nfa_edge(rx, ne_epsilon, star_end, loop_exp_start)
-				&& rx_nfa_edge(rx, ne_epsilon, loop_exp_end, star_start));
-	}
-
-
-	case r_concat:
-	{
-		struct rx_nfa_state *shared = 0;
-
-		return (rx_build_nfa(rx, rexp->params.pair.left, start, &shared)
-				&& rx_build_nfa(rx, rexp->params.pair.right, &shared,
-								end));
-	}
-
-	case r_alternate:
-	{
-		struct rx_nfa_state *ls = 0;
-		struct rx_nfa_state *le = 0;
-		struct rx_nfa_state *rs = 0;
-		struct rx_nfa_state *re = 0;
-
-		return (rx_build_nfa(rx, rexp->params.pair.left, &ls, &le)
-				&& rx_build_nfa(rx, rexp->params.pair.right, &rs, &re)
-				&& rx_nfa_edge(rx, ne_epsilon, *start, ls)
-				&& rx_nfa_edge(rx, ne_epsilon, *start, rs)
-				&& rx_nfa_edge(rx, ne_epsilon, le, *end)
-				&& rx_nfa_edge(rx, ne_epsilon, re, *end));
-	}
-
-	case r_side_effect:
-		edge = rx_nfa_edge(rx, ne_side_effect, *start, *end);
-		if (!edge)
-			return 0;
-		edge->params.side_effect = rexp->params.side_effect;
-		return 1;
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-/* RX_NAME_NFA_STATES identifies all nodes with outgoing non-epsilon
- * transitions.  Only these nodes can occur in super-states.  
- * All nodes are given an integer id. 
- * The id is non-negative if the node has non-epsilon out-transitions, negative
- * otherwise (this is because we want the non-negative ids to be used as 
- * array indexes in a few places).
- */
-
-#ifdef __STDC__
-RX_DECL void rx_name_nfa_states(struct rx *rx)
-#else
-RX_DECL void rx_name_nfa_states(rx)
-struct rx *rx;
-#endif
-{
-	struct rx_nfa_state *n = rx->nfa_states;
-
-	rx->nodec = 0;
-	rx->epsnodec = -1;
-
-	while (n) {
-		struct rx_nfa_edge *e = n->edges;
-
-		if (n->is_start)
-			n->eclosure_needed = 1;
-
-		while (e) {
-			switch (e->type) {
-			case ne_epsilon:
-			case ne_side_effect:
-				break;
-
-			case ne_cset:
-				n->id = rx->nodec++;
-				{
-					struct rx_nfa_edge *from_n = n->edges;
-
-					while (from_n) {
-						from_n->dest->eclosure_needed = 1;
-						from_n = from_n->next;
-					}
-				}
-				goto cont;
-			}
-			e = e->next;
-		}
-		n->id = rx->epsnodec--;
-	  cont:
-		n = n->next;
-	}
-	rx->epsnodec = -rx->epsnodec;
-}
-
-
-/* This page: data structures for the static part of the nfa->supernfa
- * translation.
- *
- * There are side effect lists -- lists of side effects occuring
- * along an uninterrupted, acyclic path of side-effect epsilon edges.
- * Such paths are collapsed to single edges in the course of computing
- * epsilon closures.  Such single edges are labled with a list of all
- * the side effects entailed in crossing them.  Like lists of side
- * effects are made == by the constructors below.
- *
- * There are also nfa state sets.  These are used to hold a list of all
- * states reachable from a starting state for a given type of transition
- * and side effect list.   These are also hash-consed.
- */
-
-/* The next several functions compare, construct, etc. lists of side
- * effects.  See ECLOSE_NFA (below) for details.
- */
-
-/* Ordering of rx_se_list
- * (-1, 0, 1 return value convention).
- */
-
-#ifdef __STDC__
-static int se_list_cmp(void *va, void *vb)
-#else
-static int se_list_cmp(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	struct rx_se_list *a = (struct rx_se_list *) va;
-	struct rx_se_list *b = (struct rx_se_list *) vb;
-
-	return ((va == vb)
-			? 0
-			: (!va
-			   ? -1
-			   : (!vb
-				  ? 1
-				  : ((long) a->car < (long) b->car
-					 ? 1
-					 : ((long) a->car > (long) b->car
-						? -1
-						: se_list_cmp((void *) a->cdr,
-									  (void *) b->cdr))))));
-}
-
-
-#ifdef __STDC__
-static int se_list_equal(void *va, void *vb)
-#else
-static int se_list_equal(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	return !(se_list_cmp(va, vb));
-}
-
-static struct rx_hash_rules se_list_hash_rules = {
-	se_list_equal,
-	compiler_hash_alloc,
-	compiler_free_hash,
-	compiler_hash_item_alloc,
-	compiler_free_hash_item
-};
-
-
-#ifdef __STDC__
-static struct rx_se_list *side_effect_cons(struct rx *rx,
-										   void *se,
-										   struct rx_se_list *list)
-#else
-static struct rx_se_list *side_effect_cons(rx, se, list)
-struct rx *rx;
-void *se;
-struct rx_se_list *list;
-#endif
-{
-	struct rx_se_list *l;
-
-	l = ((struct rx_se_list *) malloc(sizeof(*l)));
-	if (!l)
-		return 0;
-	l->car = se;
-	l->cdr = list;
-	return l;
-}
-
-
-#ifdef __STDC__
-static struct rx_se_list *hash_cons_se_prog(struct rx *rx,
-											struct rx_hash *memo,
-											void *car,
-											struct rx_se_list *cdr)
-#else
-static struct rx_se_list *hash_cons_se_prog(rx, memo, car, cdr)
-struct rx *rx;
-struct rx_hash *memo;
-void *car;
-struct rx_se_list *cdr;
-#endif
-{
-	long hash = (long) car ^ (long) cdr;
-	struct rx_se_list template;
-
-	template.car = car;
-	template.cdr = cdr;
-	{
-		struct rx_hash_item *it = rx_hash_store(memo, hash,
-												(void *) &template,
-												&se_list_hash_rules);
-
-		if (!it)
-			return 0;
-		if (it->data == (void *) &template) {
-			struct rx_se_list *consed;
-
-			consed = (struct rx_se_list *) malloc(sizeof(*consed));
-			if (!consed) {
-				free((char *) it);
-				return 0;
-			}
-			*consed = template;
-			it->data = (void *) consed;
-		}
-		return (struct rx_se_list *) it->data;
-	}
-}
-
-
-#ifdef __STDC__
-static struct rx_se_list *hash_se_prog(struct rx *rx, struct rx_hash *memo,
-									   struct rx_se_list *prog)
-#else
-static struct rx_se_list *hash_se_prog(rx, memo, prog)
-struct rx *rx;
-struct rx_hash *memo;
-struct rx_se_list *prog;
-#endif
-{
-	struct rx_se_list *answer = 0;
-
-	while (prog) {
-		answer = hash_cons_se_prog(rx, memo, prog->car, answer);
-		if (!answer)
-			return 0;
-		prog = prog->cdr;
-	}
-	return answer;
-}
-
-#ifdef __STDC__
-static int nfa_set_cmp(void *va, void *vb)
-#else
-static int nfa_set_cmp(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	struct rx_nfa_state_set *a = (struct rx_nfa_state_set *) va;
-	struct rx_nfa_state_set *b = (struct rx_nfa_state_set *) vb;
-
-	return ((va == vb)
-			? 0
-			: (!va
-			   ? -1
-			   : (!vb
-				  ? 1
-				  : (a->car->id < b->car->id
-					 ? 1
-					 : (a->car->id > b->car->id
-						? -1
-						: nfa_set_cmp((void *) a->cdr,
-									  (void *) b->cdr))))));
-}
-
-#ifdef __STDC__
-static int nfa_set_equal(void *va, void *vb)
-#else
-static int nfa_set_equal(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	return !nfa_set_cmp(va, vb);
-}
-
-static struct rx_hash_rules nfa_set_hash_rules = {
-	nfa_set_equal,
-	compiler_hash_alloc,
-	compiler_free_hash,
-	compiler_hash_item_alloc,
-	compiler_free_hash_item
-};
-
-
-#ifdef __STDC__
-static struct rx_nfa_state_set *nfa_set_cons(struct rx *rx,
-											 struct rx_hash *memo,
-											 struct rx_nfa_state *state,
-											 struct rx_nfa_state_set *set)
-#else
-static struct rx_nfa_state_set *nfa_set_cons(rx, memo, state, set)
-struct rx *rx;
-struct rx_hash *memo;
-struct rx_nfa_state *state;
-struct rx_nfa_state_set *set;
-#endif
-{
-	struct rx_nfa_state_set template;
-	struct rx_hash_item *node;
-
-	template.car = state;
-	template.cdr = set;
-	node = rx_hash_store(memo,
-						 (((long) state) >> 8) ^ (long) set,
-						 &template, &nfa_set_hash_rules);
-	if (!node)
-		return 0;
-	if (node->data == &template) {
-		struct rx_nfa_state_set *l;
-
-		l = (struct rx_nfa_state_set *) malloc(sizeof(*l));
-		node->data = (void *) l;
-		if (!l)
-			return 0;
-		*l = template;
-	}
-	return (struct rx_nfa_state_set *) node->data;
-}
-
-#ifdef __STDC__
-static struct rx_nfa_state_set *nfa_set_enjoin(struct rx *rx,
-											   struct rx_hash *memo,
-											   struct rx_nfa_state *state,
-											   struct rx_nfa_state_set
-											   *set)
-#else
-static struct rx_nfa_state_set *nfa_set_enjoin(rx, memo, state, set)
-struct rx *rx;
-struct rx_hash *memo;
-struct rx_nfa_state *state;
-struct rx_nfa_state_set *set;
-#endif
-{
-	if (!set || state->id < set->car->id)
-		return nfa_set_cons(rx, memo, state, set);
-	if (state->id == set->car->id)
-		return set;
-	else {
-		struct rx_nfa_state_set *newcdr
-
-			= nfa_set_enjoin(rx, memo, state, set->cdr);
-		if (newcdr != set->cdr)
-			set = nfa_set_cons(rx, memo, set->car, newcdr);
-		return set;
-	}
-}
-
-
-
-/* This page: computing epsilon closures.  The closures aren't total.
- * Each node's closures are partitioned according to the side effects entailed
- * along the epsilon edges.  Return true on success.
- */
-
-struct eclose_frame {
-	struct rx_se_list *prog_backwards;
-};
-static int eclose_node(struct rx *, struct rx_nfa_state *,
-					   struct rx_nfa_state *, struct eclose_frame *);
-RX_DECL int rx_eclose_nfa(struct rx *);
-RX_DECL void rx_delete_epsilon_transitions(struct rx *);
-static int nfacmp(void *, void *);
-static int count_hash_nodes(struct rx_hash *);
-static void nfa_set_freer(struct rx_hash_item *);
-RX_DECL int rx_compactify_nfa(struct rx *, void **, unsigned long *);
-static char *rx_cache_malloc(struct rx_cache *, int);
-static void rx_cache_free(struct rx_cache *,
-
-						  struct rx_freelist **, char *);
-static void install_transition(struct rx_superstate *,
-
-							   struct rx_inx *, rx_Bitset);
-static int qlen(struct rx_superstate *);
-static void check_cache(struct rx_cache *);
-static void semifree_superstate(struct rx_cache *);
-static void refresh_semifree_superstate
-
-	(struct rx_cache *, struct rx_superstate *);
-static void rx_refresh_this_superstate
-
-	(struct rx_cache *, struct rx_superstate *);
-static void release_superset_low(struct rx_cache *, struct rx_superset *);
-RX_DECL void rx_release_superset(struct rx *, struct rx_superset *);
-static int rx_really_free_superstate(struct rx_cache *);
-static char *rx_cache_get(struct rx_cache *, struct rx_freelist **);
-static char *rx_cache_malloc_or_get(struct rx_cache *,
-									struct rx_freelist **, int);
-static char *rx_cache_get_superstate(struct rx_cache *);
-static int supersetcmp(void *, void *);
-static struct rx_hash_item
-*superset_allocator(struct rx_hash_rules *, void *);
-static struct rx_hash
-*super_hash_allocator(struct rx_hash_rules *);
-static void super_hash_liberator(struct rx_hash *, struct rx_hash_rules *);
-static void superset_hash_item_liberator
-
-	(struct rx_hash_item *, struct rx_hash_rules *);
-static int bytes_for_cache_size(int, int);
-static void rx_morecore(struct rx_cache *);
-RX_DECL struct rx_superset
-*rx_superset_cons(struct rx *, struct rx_nfa_state *,
-
-				  struct rx_superset *);
-RX_DECL struct rx_superset
-*rx_superstate_eclosure_union
-
-	(struct rx *, struct rx_superset *, struct rx_nfa_state_set *);
-static struct rx_distinct_future
-*include_futures(struct rx *,
-				 struct rx_distinct_future *,
-
-				 struct rx_nfa_state *, struct rx_superstate *);
-RX_DECL struct rx_superstate
-*rx_superstate(struct rx *, struct rx_superset *);
-static int solve_destination(struct rx *, struct rx_distinct_future *);
-static int compute_super_edge(struct rx *,
-							  struct rx_distinct_future **,
-
-							  rx_Bitset, struct rx_superstate *,
-							  unsigned char);
-static struct rx_super_edge
-*rx_super_edge(struct rx *, struct rx_superstate *,
-
-			   rx_Bitset, struct rx_distinct_future *);
-static void install_partial_transition
-	(struct rx_superstate *, struct rx_inx *, RX_subset, int);
-RX_DECL struct rx_inx
-*rx_handle_cache_miss(struct rx *, struct rx_superstate *,
-
-					  unsigned char, void *);
-static boolean
-
-at_begline_loc_p(__const__ char *, __const__ char *, reg_syntax_t);
-static boolean at_endline_loc_p(__const__ char *, __const__ char *, int);
-static rx_Bitset
-inverse_translation(struct re_pattern_buffer *, char *,
-					rx_Bitset, unsigned char *, int);
-
-
-#ifdef __STDC__
-static int
-eclose_node(struct rx *rx, struct rx_nfa_state *outnode,
-			struct rx_nfa_state *node, struct eclose_frame *frame)
-#else
-static int eclose_node(rx, outnode, node, frame)
-struct rx *rx;
-struct rx_nfa_state *outnode;
-struct rx_nfa_state *node;
-struct eclose_frame *frame;
-#endif
-{
-	struct rx_nfa_edge *e = node->edges;
-
-	/* For each node, we follow all epsilon paths to build the closure.
-	 * The closure omits nodes that have only epsilon edges.
-	 * The closure is split into partial closures -- all the states in
-	 * a partial closure are reached by crossing the same list of
-	 * of side effects (though not necessarily the same path).
-	 */
-	if (node->mark)
-		return 1;
-	node->mark = 1;
-
-	if (node->id >= 0 || node->is_final) {
-		struct rx_possible_future **ec;
-		struct rx_se_list *prog_in_order
-			= ((struct rx_se_list *) hash_se_prog(rx,
-												  &rx->se_list_memo,
-												  frame->prog_backwards));
-		int cmp;
-
-		ec = &outnode->futures;
-
-		while (*ec) {
-			cmp =
-				se_list_cmp((void *) (*ec)->effects,
-							(void *) prog_in_order);
-			if (cmp <= 0)
-				break;
-			ec = &(*ec)->next;
-		}
-		if (!*ec || (cmp < 0)) {
-			struct rx_possible_future *saved = *ec;
-
-			*ec = rx_possible_future(rx, prog_in_order);
-			(*ec)->next = saved;
-			if (!*ec)
-				return 0;
-		}
-		if (node->id >= 0) {
-			(*ec)->destset = nfa_set_enjoin(rx, &rx->set_list_memo,
-											node, (*ec)->destset);
-			if (!(*ec)->destset)
-				return 0;
-		}
-	}
-
-	while (e) {
-		switch (e->type) {
-		case ne_epsilon:
-			if (!eclose_node(rx, outnode, e->dest, frame))
-				return 0;
-			break;
-		case ne_side_effect:
-		{
-			frame->prog_backwards = side_effect_cons(rx,
-													 e->params.side_effect,
-													 frame->prog_backwards);
-			if (!frame->prog_backwards)
-				return 0;
-			if (!eclose_node(rx, outnode, e->dest, frame))
-				return 0;
-			{
-				struct rx_se_list *dying = frame->prog_backwards;
-
-				frame->prog_backwards = frame->prog_backwards->cdr;
-				free((char *) dying);
-			}
-			break;
-		}
-		default:
-			break;
-		}
-		e = e->next;
-	}
-	node->mark = 0;
-	return 1;
-}
-
-#ifdef __STDC__
-RX_DECL int rx_eclose_nfa(struct rx *rx)
-#else
-RX_DECL int rx_eclose_nfa(rx)
-struct rx *rx;
-#endif
-{
-	struct rx_nfa_state *n = rx->nfa_states;
-	struct eclose_frame frame;
-	static int rx_id = 0;
-
-	frame.prog_backwards = 0;
-	rx->rx_id = rx_id++;
-	bzero(&rx->se_list_memo, sizeof(rx->se_list_memo));
-	bzero(&rx->set_list_memo, sizeof(rx->set_list_memo));
-	while (n) {
-		n->futures = 0;
-		if (n->eclosure_needed && !eclose_node(rx, n, n, &frame))
-			return 0;
-		/* clear_marks (rx); */
-		n = n->next;
-	}
-	return 1;
-}
-
-
-/* This deletes epsilon edges from an NFA.  After running eclose_node,
- * we have no more need for these edges.  They are removed to simplify
- * further operations on the NFA.
- */
-
-#ifdef __STDC__
-RX_DECL void rx_delete_epsilon_transitions(struct rx *rx)
-#else
-RX_DECL void rx_delete_epsilon_transitions(rx)
-struct rx *rx;
-#endif
-{
-	struct rx_nfa_state *n = rx->nfa_states;
-	struct rx_nfa_edge **e;
-
-	while (n) {
-		e = &n->edges;
-		while (*e) {
-			struct rx_nfa_edge *t;
-
-			switch ((*e)->type) {
-			case ne_epsilon:
-			case ne_side_effect:
-				t = *e;
-				*e = t->next;
-				rx_free_nfa_edge(t);
-				break;
-
-			default:
-				e = &(*e)->next;
-				break;
-			}
-		}
-		n = n->next;
-	}
-}
-
-
-/* This page: storing the nfa in a contiguous region of memory for
- * subsequent conversion to a super-nfa.
- */
-
-/* This is for qsort on an array of nfa_states. The order
- * is based on state ids and goes 
- *		[0...MAX][MIN..-1] where (MAX>=0) and (MIN<0)
- * This way, positive ids double as array indices.
- */
-
-#ifdef __STDC__
-static int nfacmp(void *va, void *vb)
-#else
-static int nfacmp(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	struct rx_nfa_state **a = (struct rx_nfa_state **) va;
-	struct rx_nfa_state **b = (struct rx_nfa_state **) vb;
-
-	return (*a == *b			/* &&&& 3.18 */
-			? 0 : (((*a)->id < 0) == ((*b)->id < 0)
-				   ? (((*a)->id < (*b)->id) ? -1 : 1)
-				   : (((*a)->id < 0)
-					  ? 1 : -1)));
-}
-
-#ifdef __STDC__
-static int count_hash_nodes(struct rx_hash *st)
-#else
-static int count_hash_nodes(st)
-struct rx_hash *st;
-#endif
-{
-	int x;
-	int count = 0;
-
-	for (x = 0; x < 13; ++x)
-		count += ((st->children[x])
-				  ? count_hash_nodes(st->children[x])
-				  : st->bucket_size[x]);
-
-	return count;
-}
-
-
-#ifdef __STDC__
-static void se_memo_freer(struct rx_hash_item *node)
-#else
-static void se_memo_freer(node)
-struct rx_hash_item *node;
-#endif
-{
-	free((char *) node->data);
-}
-
-
-#ifdef __STDC__
-static void nfa_set_freer(struct rx_hash_item *node)
-#else
-static void nfa_set_freer(node)
-struct rx_hash_item *node;
-#endif
-{
-	free((char *) node->data);
-}
-
-
-/* This copies an entire NFA into a single malloced block of memory.
- * Mostly this is for compatability with regex.c, though it is convenient
- * to have the nfa nodes in an array.
- */
-
-#ifdef __STDC__
-RX_DECL int
-rx_compactify_nfa(struct rx *rx, void **mem, unsigned long *size)
-#else
-RX_DECL int rx_compactify_nfa(rx, mem, size)
-struct rx *rx;
-void **mem;
-unsigned long *size;
-#endif
-{
-	int total_nodec;
-	struct rx_nfa_state *n;
-	int edgec = 0;
-	int eclosec = 0;
-	int se_list_consc = count_hash_nodes(&rx->se_list_memo);
-	int nfa_setc = count_hash_nodes(&rx->set_list_memo);
-	unsigned long total_size;
-
-	/* This takes place in two stages.   First, the total size of the
-	 * nfa is computed, then structures are copied.  
-	 */
-	n = rx->nfa_states;
-	total_nodec = 0;
-	while (n) {
-		struct rx_nfa_edge *e = n->edges;
-		struct rx_possible_future *ec = n->futures;
-
-		++total_nodec;
-		while (e) {
-			++edgec;
-			e = e->next;
-		}
-		while (ec) {
-			++eclosec;
-			ec = ec->next;
-		}
-		n = n->next;
-	}
-
-	total_size = (total_nodec * sizeof(struct rx_nfa_state)
-				  + edgec * rx_sizeof_bitset(rx->local_cset_size)
-				  + edgec * sizeof(struct rx_nfa_edge)
-				  + nfa_setc * sizeof(struct rx_nfa_state_set)
-				  + eclosec * sizeof(struct rx_possible_future)
-				  + se_list_consc * sizeof(struct rx_se_list)
-				  + rx->reserved);
-
-	if (total_size > *size) {
-		*mem = remalloc(*mem, total_size);
-		if (*mem)
-			*size = total_size;
-		else
-			return 0;
-	}
-	/* Now we've allocated the memory; this copies the NFA. */
-	{
-		static struct rx_nfa_state **scratch = 0;
-		static int scratch_alloc = 0;
-		struct rx_nfa_state *state_base = (struct rx_nfa_state *) *mem;
-		struct rx_nfa_state *new_state = state_base;
-		struct rx_nfa_edge *new_edge = (struct rx_nfa_edge *)
-			((char *) state_base + total_nodec * sizeof(struct rx_nfa_state));
-		struct rx_se_list *new_se_list = (struct rx_se_list *)
-			((char *) new_edge + edgec * sizeof(struct rx_nfa_edge));
-		struct rx_possible_future *new_close =
-			((struct rx_possible_future *)
-			 ((char *) new_se_list
-
-			  + se_list_consc * sizeof(struct rx_se_list)));
-		struct rx_nfa_state_set *new_nfa_set = ((struct rx_nfa_state_set *)
-
-												((char *) new_close +
-												 eclosec *
-
-												 sizeof(struct
-														rx_possible_future)));
-		char *new_bitset =
-
-			((char *) new_nfa_set +
-			 nfa_setc * sizeof(struct rx_nfa_state_set));
-		int x;
-		struct rx_nfa_state *n;
-
-		if (scratch_alloc < total_nodec) {
-			scratch = ((struct rx_nfa_state **)
-					   remalloc(scratch, total_nodec * sizeof(*scratch)));
-			if (scratch)
-				scratch_alloc = total_nodec;
-			else {
-				scratch_alloc = 0;
-				return 0;
-			}
-		}
-
-		for (x = 0, n = rx->nfa_states; n; n = n->next)
-			scratch[x++] = n;
-
-		qsort(scratch, total_nodec, sizeof(struct rx_nfa_state *),
-			  (__compar_fn_t) nfacmp);
-
-		for (x = 0; x < total_nodec; ++x) {
-			struct rx_possible_future *eclose = scratch[x]->futures;
-			struct rx_nfa_edge *edge = scratch[x]->edges;
-			struct rx_nfa_state *cn = new_state++;
-
-			cn->futures = 0;
-			cn->edges = 0;
-			cn->next = (x == total_nodec - 1) ? 0 : (cn + 1);
-			cn->id = scratch[x]->id;
-			cn->is_final = scratch[x]->is_final;
-			cn->is_start = scratch[x]->is_start;
-			cn->mark = 0;
-			while (edge) {
-				int indx = (edge->dest->id < 0
-							? (total_nodec + edge->dest->id)
-
-							: edge->dest->id);
-				struct rx_nfa_edge *e = new_edge++;
-				rx_Bitset cset = (rx_Bitset) new_bitset;
-
-				new_bitset += rx_sizeof_bitset(rx->local_cset_size);
-				rx_bitset_null(rx->local_cset_size, cset);
-				rx_bitset_union(rx->local_cset_size, cset,
-								edge->params.cset);
-				e->next = cn->edges;
-				cn->edges = e;
-				e->type = edge->type;
-				e->dest = state_base + indx;
-				e->params.cset = cset;
-				edge = edge->next;
-			}
-			while (eclose) {
-				struct rx_possible_future *ec = new_close++;
-				struct rx_hash_item *sp;
-				struct rx_se_list **sepos;
-				struct rx_se_list *sesrc;
-				struct rx_nfa_state_set *destlst;
-				struct rx_nfa_state_set **destpos;
-
-				ec->next = cn->futures;
-				cn->futures = ec;
-				for (sepos = &ec->effects, sesrc = eclose->effects;
-					 sesrc; sesrc = sesrc->cdr, sepos = &(*sepos)->cdr) {
-					sp = rx_hash_find(&rx->se_list_memo,
-									  (long) sesrc->
-									  car ^ (long) sesrc->cdr, sesrc,
-									  &se_list_hash_rules);
-					if (sp->binding) {
-						sesrc = (struct rx_se_list *) sp->binding;
-						break;
-					}
-					*new_se_list = *sesrc;
-					sp->binding = (void *) new_se_list;
-					*sepos = new_se_list;
-					++new_se_list;
-				}
-				*sepos = sesrc;
-				for (destpos = &ec->destset, destlst = eclose->destset;
-					 destlst;
-					 destpos = &(*destpos)->cdr, destlst = destlst->cdr) {
-					sp = rx_hash_find(&rx->set_list_memo,
-									  ((((long) destlst->car) >> 8)
-									   ^ (long) destlst->cdr),
-									  destlst, &nfa_set_hash_rules);
-					if (sp->binding) {
-						destlst = (struct rx_nfa_state_set *) sp->binding;
-						break;
-					}
-					*new_nfa_set = *destlst;
-					new_nfa_set->car = state_base + destlst->car->id;
-					sp->binding = (void *) new_nfa_set;
-					*destpos = new_nfa_set;
-					++new_nfa_set;
-				}
-				*destpos = destlst;
-				eclose = eclose->next;
-			}
-		}
-	}
-	rx_free_hash_table(&rx->se_list_memo, se_memo_freer,
-					   &se_list_hash_rules);
-	bzero(&rx->se_list_memo, sizeof(rx->se_list_memo));
-	rx_free_hash_table(&rx->set_list_memo, nfa_set_freer,
-					   &nfa_set_hash_rules);
-	bzero(&rx->set_list_memo, sizeof(rx->set_list_memo));
-
-	rx_free_nfa(rx);
-	rx->nfa_states = (struct rx_nfa_state *) *mem;
-	return 1;
-}
-
-
-/* The functions in the next several pages define the lazy-NFA-conversion used
- * by matchers.  The input to this construction is an NFA such as 
- * is built by compactify_nfa (rx.c).  The output is the superNFA.
- */
-
-/* Match engines can use arbitrary values for opcodes.  So, the parse tree 
- * is built using instructions names (enum rx_opcode), but the superstate
- * nfa is populated with mystery opcodes (void *).
- *
- * For convenience, here is an id table.  The opcodes are == to their inxs
- *
- * The lables in re_search_2 would make good values for instructions.
- */
-
-void *rx_id_instruction_table[rx_num_instructions] = {
-	(void *) rx_backtrack_point,
-	(void *) rx_do_side_effects,
-	(void *) rx_cache_miss,
-	(void *) rx_next_char,
-	(void *) rx_backtrack,
-	(void *) rx_error_inx
-};
-
-
-
-/* Memory mgt. for superstate graphs. */
-
-#ifdef __STDC__
-static char *rx_cache_malloc(struct rx_cache *cache, int bytes)
-#else
-static char *rx_cache_malloc(cache, bytes)
-struct rx_cache *cache;
-int bytes;
-#endif
-{
-	while (cache->bytes_left < bytes) {
-		if (cache->memory_pos)
-			cache->memory_pos = cache->memory_pos->next;
-		if (!cache->memory_pos) {
-			cache->morecore(cache);
-			if (!cache->memory_pos)
-				return 0;
-		}
-		cache->bytes_left = cache->memory_pos->bytes;
-		cache->memory_addr = ((char *) cache->memory_pos
-
-							  + sizeof(struct rx_blocklist));
-	}
-	cache->bytes_left -= bytes;
-	{
-		char *addr = cache->memory_addr;
-
-		cache->memory_addr += bytes;
-		return addr;
-	}
-}
-
-#ifdef __STDC__
-static void
-rx_cache_free(struct rx_cache *cache,
-			  struct rx_freelist **freelist, char *mem)
-#else
-static void rx_cache_free(cache, freelist, mem)
-struct rx_cache *cache;
-struct rx_freelist **freelist;
-char *mem;
-#endif
-{
-	struct rx_freelist *it = (struct rx_freelist *) mem;
-
-	it->next = *freelist;
-	*freelist = it;
-}
-
-/* The partially instantiated superstate graph has a transition 
- * table at every node.  There is one entry for every character.
- * This fills in the transition for a set.
- */
-#ifdef __STDC__
-static void
-install_transition(struct rx_superstate *super,
-				   struct rx_inx *answer, rx_Bitset trcset)
-#else
-static void install_transition(super, answer, trcset)
-struct rx_superstate *super;
-struct rx_inx *answer;
-rx_Bitset trcset;
-#endif
-{
-	struct rx_inx *transitions = super->transitions;
-	int chr;
-
-	for (chr = 0; chr < 256;)
-		if (!*trcset) {
-			++trcset;
-			chr += 32;
-		} else {
-			RX_subset sub = *trcset;
-			RX_subset mask = 1;
-			int bound = chr + 32;
-
-			while (chr < bound) {
-				if (sub & mask)
-					transitions[chr] = *answer;
-				++chr;
-				mask <<= 1;
-			}
-			++trcset;
-		}
-}
-
-#ifdef __STDC__
-static int qlen(struct rx_superstate *q)
-#else
-static int qlen(q)
-struct rx_superstate *q;
-#endif
-{
-	int count = 1;
-	struct rx_superstate *it;
-
-	if (!q)
-		return 0;
-	for (it = q->next_recyclable; it != q; it = it->next_recyclable)
-		++count;
-	return count;
-}
-
-#ifdef __STDC__
-static void check_cache(struct rx_cache *cache)
-#else
-static void check_cache(cache)
-struct rx_cache *cache;
-#endif
-{
-	struct rx_cache *you_fucked_up = 0;
-	int total = cache->superstates;
-	int semi = cache->semifree_superstates;
-
-	if (semi != qlen(cache->semifree_superstate))
-		check_cache(you_fucked_up);
-	if ((total - semi) != qlen(cache->lru_superstate))
-		check_cache(you_fucked_up);
-}
-
-/* When a superstate is old and neglected, it can enter a 
- * semi-free state.  A semi-free state is slated to die.
- * Incoming transitions to a semi-free state are re-written
- * to cause an (interpreted) fault when they are taken.
- * The fault handler revives the semi-free state, patches
- * incoming transitions back to normal, and continues.
- *
- * The idea is basicly to free in two stages, aborting 
- * between the two if the state turns out to be useful again.
- * When a free is aborted, the rescued superstate is placed
- * in the most-favored slot to maximize the time until it
- * is next semi-freed.
- */
-
-#ifdef __STDC__
-static void semifree_superstate(struct rx_cache *cache)
-#else
-static void semifree_superstate(cache)
-struct rx_cache *cache;
-#endif
-{
-	int disqualified = cache->semifree_superstates;
-
-	if (disqualified == cache->superstates)
-		return;
-	while (cache->lru_superstate->locks) {
-		cache->lru_superstate = cache->lru_superstate->next_recyclable;
-		++disqualified;
-		if (disqualified == cache->superstates)
-			return;
-	}
-	{
-		struct rx_superstate *it = cache->lru_superstate;
-
-		it->next_recyclable->prev_recyclable = it->prev_recyclable;
-		it->prev_recyclable->next_recyclable = it->next_recyclable;
-		cache->lru_superstate = (it == it->next_recyclable
-								 ? 0 : it->next_recyclable);
-		if (!cache->semifree_superstate) {
-			cache->semifree_superstate = it;
-			it->next_recyclable = it;
-			it->prev_recyclable = it;
-		} else {
-			it->prev_recyclable =
-				cache->semifree_superstate->prev_recyclable;
-			it->next_recyclable = cache->semifree_superstate;
-			it->prev_recyclable->next_recyclable = it;
-			it->next_recyclable->prev_recyclable = it;
-		}
-		{
-			struct rx_distinct_future *df;
-
-			it->is_semifree = 1;
-			++cache->semifree_superstates;
-			df = it->transition_refs;
-			if (df) {
-				df->prev_same_dest->next_same_dest = 0;
-				for (df = it->transition_refs; df; df = df->next_same_dest) {
-					df->future_frame.inx =
-						cache->instruction_table[rx_cache_miss];
-					df->future_frame.data = 0;
-					df->future_frame.data_2 = (void *) df;
-					/* If there are any NEXT-CHAR instruction frames that
-					 * refer to this state, we convert them to CACHE-MISS frames.
-					 */
-					if (!df->effects
-						&& (df->edge->options->next_same_super_edge[0]
-							== df->edge->options))
-						install_transition(df->present, &df->future_frame,
-										   df->edge->cset);
-				}
-				df = it->transition_refs;
-				df->prev_same_dest->next_same_dest = df;
-			}
-		}
-	}
-}
-
-#ifdef __STDC__
-static void
-refresh_semifree_superstate(struct rx_cache *cache,
-							struct rx_superstate *super)
-#else
-static void refresh_semifree_superstate(cache, super)
-struct rx_cache *cache;
-struct rx_superstate *super;
-#endif
-{
-	struct rx_distinct_future *df;
-
-	if (super->transition_refs) {
-		super->transition_refs->prev_same_dest->next_same_dest = 0;
-		for (df = super->transition_refs; df; df = df->next_same_dest) {
-			df->future_frame.inx = cache->instruction_table[rx_next_char];
-			df->future_frame.data = (void *) super->transitions;
-			/* CACHE-MISS instruction frames that refer to this state,
-			 * must be converted to NEXT-CHAR frames.
-			 */
-			if (!df->effects && (df->edge->options->next_same_super_edge[0]
-								 == df->edge->options))
-				install_transition(df->present, &df->future_frame,
-								   df->edge->cset);
-		}
-		super->transition_refs->prev_same_dest->next_same_dest
-			= super->transition_refs;
-	}
-	if (cache->semifree_superstate == super)
-		cache->semifree_superstate = (super->prev_recyclable == super
-									  ? 0 : super->prev_recyclable);
-	super->next_recyclable->prev_recyclable = super->prev_recyclable;
-	super->prev_recyclable->next_recyclable = super->next_recyclable;
-
-	if (!cache->lru_superstate)
-		(cache->lru_superstate
-		 = super->next_recyclable = super->prev_recyclable = super);
-	else {
-		super->next_recyclable = cache->lru_superstate;
-		super->prev_recyclable = cache->lru_superstate->prev_recyclable;
-		super->next_recyclable->prev_recyclable = super;
-		super->prev_recyclable->next_recyclable = super;
-	}
-	super->is_semifree = 0;
-	--cache->semifree_superstates;
-}
-
-#ifdef __STDC__
-static void
-rx_refresh_this_superstate(struct rx_cache *cache,
-						   struct rx_superstate *superstate)
-#else
-static void rx_refresh_this_superstate(cache, superstate)
-struct rx_cache *cache;
-struct rx_superstate *superstate;
-#endif
-{
-	if (superstate->is_semifree)
-		refresh_semifree_superstate(cache, superstate);
-	else if (cache->lru_superstate == superstate)
-		cache->lru_superstate = superstate->next_recyclable;
-	else if (superstate != cache->lru_superstate->prev_recyclable) {
-		superstate->next_recyclable->prev_recyclable
-			= superstate->prev_recyclable;
-		superstate->prev_recyclable->next_recyclable
-			= superstate->next_recyclable;
-		superstate->next_recyclable = cache->lru_superstate;
-		superstate->prev_recyclable =
-			cache->lru_superstate->prev_recyclable;
-		superstate->next_recyclable->prev_recyclable = superstate;
-		superstate->prev_recyclable->next_recyclable = superstate;
-	}
-}
-
-#ifdef __STDC__
-static void
-release_superset_low(struct rx_cache *cache, struct rx_superset *set)
-#else
-static void release_superset_low(cache, set)
-struct rx_cache *cache;
-struct rx_superset *set;
-#endif
-{
-	if (!--set->refs) {
-		if (set->cdr)
-			release_superset_low(cache, set->cdr);
-
-		set->starts_for = 0;
-
-		rx_hash_free
-			(rx_hash_find
-			 (&cache->superset_table,
-			  (unsigned long) set->car ^ set->
-			  id ^ (unsigned long) set->cdr, (void *) set,
-			  &cache->superset_hash_rules), &cache->superset_hash_rules);
-		rx_cache_free(cache, &cache->free_supersets, (char *) set);
-	}
-}
-
-#ifdef __STDC__
-RX_DECL void rx_release_superset(struct rx *rx, struct rx_superset *set)
-#else
-RX_DECL void rx_release_superset(rx, set)
-struct rx *rx;
-struct rx_superset *set;
-#endif
-{
-	release_superset_low(rx->cache, set);
-}
-
-/* This tries to add a new superstate to the superstate freelist.
- * It might, as a result, free some edge pieces or hash tables.
- * If nothing can be freed because too many locks are being held, fail.
- */
-
-#ifdef __STDC__
-static int rx_really_free_superstate(struct rx_cache *cache)
-#else
-static int rx_really_free_superstate(cache)
-struct rx_cache *cache;
-#endif
-{
-	int locked_superstates = 0;
-	struct rx_superstate *it;
-
-	if (!cache->superstates)
-		return 0;
-
-	{
-		/* This is a total guess.  The idea is that we should expect as
-		 * many misses as we've recently experienced.  I.e., cache->misses
-		 * should be the same as cache->semifree_superstates.
-		 */
-		while ((cache->hits + cache->misses) > cache->superstates_allowed) {
-			cache->hits >>= 1;
-			cache->misses >>= 1;
-		}
-		if (((cache->hits + cache->misses) * cache->semifree_superstates)
-			< (cache->superstates * cache->misses)) {
-			semifree_superstate(cache);
-			semifree_superstate(cache);
-		}
-	}
-
-	while (cache->semifree_superstate && cache->semifree_superstate->locks) {
-		refresh_semifree_superstate(cache, cache->semifree_superstate);
-		++locked_superstates;
-		if (locked_superstates == cache->superstates)
-			return 0;
-	}
-
-	if (cache->semifree_superstate) {
-		it = cache->semifree_superstate;
-		it->next_recyclable->prev_recyclable = it->prev_recyclable;
-		it->prev_recyclable->next_recyclable = it->next_recyclable;
-		cache->semifree_superstate = ((it == it->next_recyclable)
-									  ? 0 : it->next_recyclable);
-		--cache->semifree_superstates;
-	} else {
-		while (cache->lru_superstate->locks) {
-			cache->lru_superstate = cache->lru_superstate->next_recyclable;
-			++locked_superstates;
-			if (locked_superstates == cache->superstates)
-				return 0;
-		}
-		it = cache->lru_superstate;
-		it->next_recyclable->prev_recyclable = it->prev_recyclable;
-		it->prev_recyclable->next_recyclable = it->next_recyclable;
-		cache->lru_superstate = ((it == it->next_recyclable)
-								 ? 0 : it->next_recyclable);
-	}
-
-	if (it->transition_refs) {
-		struct rx_distinct_future *df;
-
-		for (df = it->transition_refs,
-			 df->prev_same_dest->next_same_dest = 0;
-			 df; df = df->next_same_dest) {
-			df->future_frame.inx = cache->instruction_table[rx_cache_miss];
-			df->future_frame.data = 0;
-			df->future_frame.data_2 = (void *) df;
-			df->future = 0;
-		}
-		it->transition_refs->prev_same_dest->next_same_dest =
-			it->transition_refs;
-	}
-	{
-		struct rx_super_edge *tc = it->edges;
-
-		while (tc) {
-			struct rx_distinct_future *df;
-			struct rx_super_edge *tct = tc->next;
-
-			df = tc->options;
-			df->next_same_super_edge[1]->next_same_super_edge[0] = 0;
-			while (df) {
-				struct rx_distinct_future *dft = df;
-
-				df = df->next_same_super_edge[0];
-
-
-				if (dft->future && dft->future->transition_refs == dft) {
-					dft->future->transition_refs = dft->next_same_dest;
-					if (dft->future->transition_refs == dft)
-						dft->future->transition_refs = 0;
-				}
-				dft->next_same_dest->prev_same_dest = dft->prev_same_dest;
-				dft->prev_same_dest->next_same_dest = dft->next_same_dest;
-				rx_cache_free(cache, &cache->free_discernable_futures,
-							  (char *) dft);
-			}
-			rx_cache_free(cache, &cache->free_transition_classes,
-						  (char *) tc);
-			tc = tct;
-		}
-	}
-
-	if (it->contents->superstate == it)
-		it->contents->superstate = 0;
-	release_superset_low(cache, it->contents);
-	rx_cache_free(cache, &cache->free_superstates, (char *) it);
-	--cache->superstates;
-	return 1;
-}
-
-#ifdef __STDC__
-static char *rx_cache_get(struct rx_cache *cache,
-						  struct rx_freelist **freelist)
-#else
-static char *rx_cache_get(cache, freelist)
-struct rx_cache *cache;
-struct rx_freelist **freelist;
-#endif
-{
-	while (!*freelist && rx_really_free_superstate(cache));
-	if (!*freelist)
-		return 0;
-	{
-		struct rx_freelist *it = *freelist;
-
-		*freelist = it->next;
-		return (char *) it;
-	}
-}
-
-#ifdef __STDC__
-static char *rx_cache_malloc_or_get(struct rx_cache *cache,
-									struct rx_freelist **freelist,
-									int bytes)
-#else
-static char *rx_cache_malloc_or_get(cache, freelist, bytes)
-struct rx_cache *cache;
-struct rx_freelist **freelist;
-int bytes;
-#endif
-{
-	if (!*freelist) {
-		char *answer = rx_cache_malloc(cache, bytes);
-
-		if (answer)
-			return answer;
-	}
-
-	return rx_cache_get(cache, freelist);
-}
-
-#ifdef __STDC__
-static char *rx_cache_get_superstate(struct rx_cache *cache)
-#else
-static char *rx_cache_get_superstate(cache)
-struct rx_cache *cache;
-#endif
-{
-	char *answer;
-	int bytes = (sizeof(struct rx_superstate)
-				 + cache->local_cset_size * sizeof(struct rx_inx));
-
-	if (!cache->free_superstates
-		&& (cache->superstates < cache->superstates_allowed)) {
-		answer = rx_cache_malloc(cache, bytes);
-		if (answer) {
-			++cache->superstates;
-			return answer;
-		}
-	}
-	answer = rx_cache_get(cache, &cache->free_superstates);
-	if (!answer) {
-		answer = rx_cache_malloc(cache, bytes);
-		if (answer)
-			++cache->superstates_allowed;
-	}
-	++cache->superstates;
-	return answer;
-}
-
-
-
-#ifdef __STDC__
-static int supersetcmp(void *va, void *vb)
-#else
-static int supersetcmp(va, vb)
-void *va;
-void *vb;
-#endif
-{
-	struct rx_superset *a = (struct rx_superset *) va;
-	struct rx_superset *b = (struct rx_superset *) vb;
-
-	return ((a == b)
-			|| (a && b && (a->car == b->car) && (a->cdr == b->cdr)));
-}
-
-#ifdef __STDC__
-static struct rx_hash_item *superset_allocator(struct rx_hash_rules *rules,
-											   void *val)
-#else
-static struct rx_hash_item *superset_allocator(rules, val)
-struct rx_hash_rules *rules;
-void *val;
-#endif
-{
-	struct rx_cache *cache = ((struct rx_cache *)
-							  ((char *) rules
-							   -
-
-							   (unsigned
-								long) (&((struct rx_cache *)
-										 0)->superset_hash_rules)));
-	struct rx_superset *template = (struct rx_superset *) val;
-	struct rx_superset *newset
-		= ((struct rx_superset *) rx_cache_malloc_or_get(cache,
-														 &cache->free_supersets,
-														 sizeof
-
-														 (*template)));
-	if (!newset)
-		return 0;
-	newset->refs = 0;
-	newset->car = template->car;
-	newset->id = template->car->id;
-	newset->cdr = template->cdr;
-	newset->superstate = 0;
-	rx_protect_superset(rx, template->cdr);
-	newset->hash_item.data = (void *) newset;
-	newset->hash_item.binding = 0;
-	return &newset->hash_item;
-}
-
-#ifdef __STDC__
-static struct rx_hash *super_hash_allocator(struct rx_hash_rules *rules)
-#else
-static struct rx_hash *super_hash_allocator(rules)
-struct rx_hash_rules *rules;
-#endif
-{
-	struct rx_cache *cache = ((struct rx_cache *)
-							  ((char *) rules
-							   -
-
-							   (unsigned
-								long) (&((struct rx_cache *)
-										 0)->superset_hash_rules)));
-	return ((struct rx_hash *)
-			rx_cache_malloc_or_get(cache, &cache->free_hash,
-
-								   sizeof(struct rx_hash)));
-}
-
-
-#ifdef __STDC__
-static void
-super_hash_liberator(struct rx_hash *hash, struct rx_hash_rules *rules)
-#else
-static void super_hash_liberator(hash, rules)
-struct rx_hash *hash;
-struct rx_hash_rules *rules;
-#endif
-{
-	struct rx_cache *cache = ((struct rx_cache *)
-
-							  (char *) rules -
-							  (long) (&
-
-									  ((struct rx_cache *)
-									   0)->superset_hash_rules));
-	rx_cache_free(cache, &cache->free_hash, (char *) hash);
-}
-
-#ifdef __STDC__
-static void
-superset_hash_item_liberator(struct rx_hash_item *it,
-							 struct rx_hash_rules *rules)
-#else
-static void superset_hash_item_liberator(it, rules)	/* Well, it does ya know. */
-struct rx_hash_item *it;
-struct rx_hash_rules *rules;
-#endif
-{
-}
-
-int rx_cache_bound = 128;
-static int rx_default_cache_got = 0;
-
-#ifdef __STDC__
-static int bytes_for_cache_size(int supers, int cset_size)
-#else
-static int bytes_for_cache_size(supers, cset_size)
-int supers;
-int cset_size;
-#endif
-{
-	/* What the hell is this? !!! */
-	return (int)
-		((float) supers * ((1.03 * (float) (rx_sizeof_bitset(cset_size)
-											+
-											sizeof(struct rx_super_edge)))
-						   +
-						   (1.80 *
-							(float) sizeof(struct rx_possible_future)) +
-						   (float) (sizeof(struct rx_superstate)
-									+ cset_size * sizeof(struct rx_inx))));
-}
-
-#ifdef __STDC__
-static void rx_morecore(struct rx_cache *cache)
-#else
-static void rx_morecore(cache)
-struct rx_cache *cache;
-#endif
-{
-	if (rx_default_cache_got >= rx_cache_bound)
-		return;
-
-	rx_default_cache_got += 16;
-	cache->superstates_allowed = rx_cache_bound;
-	{
-		struct rx_blocklist **pos = &cache->memory;
-		int size = bytes_for_cache_size(16, cache->local_cset_size);
-
-		while (*pos)
-			pos = &(*pos)->next;
-		*pos = ((struct rx_blocklist *)
-				malloc(size + sizeof(struct rx_blocklist)));
-
-		if (!*pos)
-			return;
-
-		(*pos)->next = 0;
-		(*pos)->bytes = size;
-		cache->memory_pos = *pos;
-		cache->memory_addr = (char *) *pos + sizeof(**pos);
-		cache->bytes_left = size;
-	}
-}
-
-static struct rx_cache default_cache = {
-	{
-	 supersetcmp,
-	 super_hash_allocator,
-	 super_hash_liberator,
-	 superset_allocator,
-	 superset_hash_item_liberator,
-	 },
-	0,
-	0,
-	0,
-	0,
-	rx_morecore,
-
-	0,
-	0,
-	0,
-	0,
-	0,
-
-	0,
-	0,
-
-	0,
-
-	0,
-	0,
-	0,
-	0,
-	128,
-
-	256,
-	rx_id_instruction_table,
-
-	{
-	 0,
-	 0,
-	 {0},
-	 {0},
-	 {0}
-	 }
-};
-
-/* This adds an element to a superstate set.  These sets are lists, such
- * that lists with == elements are ==.  The empty set is returned by
- * superset_cons (rx, 0, 0) and is NOT equivelent to 
- * (struct rx_superset)0.
- */
-
-#ifdef __STDC__
-RX_DECL struct rx_superset *rx_superset_cons(struct rx *rx,
-											 struct rx_nfa_state *car,
-											 struct rx_superset *cdr)
-#else
-RX_DECL struct rx_superset *rx_superset_cons(rx, car, cdr)
-struct rx *rx;
-struct rx_nfa_state *car;
-struct rx_superset *cdr;
-#endif
-{
-	struct rx_cache *cache = rx->cache;
-
-	if (!car && !cdr) {
-		if (!cache->empty_superset) {
-			cache->empty_superset = ((struct rx_superset *)
-									 rx_cache_malloc_or_get(cache,
-															&cache->free_supersets,
-
-															sizeof(struct
-																   rx_superset)));
-			if (!cache->empty_superset)
-				return 0;
-			bzero(cache->empty_superset, sizeof(struct rx_superset));
-
-			cache->empty_superset->refs = 1000;
-		}
-		return cache->empty_superset;
-	}
-	{
-		struct rx_superset template;
-		struct rx_hash_item *hit;
-
-		template.car = car;
-		template.cdr = cdr;
-		template.id = car->id;
-		/* While hash_store will protect cdr itself it might first allocate hash
-		   tables and stuff which might cause it to be garbage collected before
-		   it's protected -- [gsstark:19961026.2155EST] */
-		rx_protect_superset(rx, cdr);
-		hit = rx_hash_store(&cache->superset_table,
-							(unsigned long) car ^ car->id ^ (unsigned long)
-							cdr, (void *) &template,
-							&cache->superset_hash_rules);
-		rx_release_superset(rx, cdr);
-		return (hit ? (struct rx_superset *) hit->data : 0);
-	}
-}
-
-/* This computes a union of two NFA state sets.  The sets do not have the
- * same representation though.  One is a RX_SUPERSET structure (part
- * of the superstate NFA) and the other is an NFA_STATE_SET (part of the NFA).
- */
-
-#ifdef __STDC__
-RX_DECL struct rx_superset *rx_superstate_eclosure_union
-	(struct rx *rx, struct rx_superset *set, struct rx_nfa_state_set *ecl)
-#else
-RX_DECL struct rx_superset *rx_superstate_eclosure_union(rx, set, ecl)
-struct rx *rx;
-struct rx_superset *set;
-struct rx_nfa_state_set *ecl;
-#endif
-{
-	if (!ecl)
-		return set;
-
-	if (!set->car)
-		return rx_superset_cons(rx, ecl->car,
-								rx_superstate_eclosure_union(rx, set,
-															 ecl->cdr));
-	if (set->car == ecl->car)
-		return rx_superstate_eclosure_union(rx, set, ecl->cdr);
-
-	{
-		struct rx_superset *tail;
-		struct rx_nfa_state *first;
-
-		if (set->car > ecl->car) {
-			tail = rx_superstate_eclosure_union(rx, set->cdr, ecl);
-			first = set->car;
-		} else {
-			tail = rx_superstate_eclosure_union(rx, set, ecl->cdr);
-			first = ecl->car;
-		}
-		if (!tail)
-			return 0;
-		else {
-			struct rx_superset *answer;
-
-			answer = rx_superset_cons(rx, first, tail);
-			if (!answer) {
-				rx_protect_superset(rx, tail);
-				rx_release_superset(rx, tail);
-				return 0;
-			} else
-				return answer;
-		}
-	}
-}
-
-
-
-
-/*
- * This makes sure that a list of rx_distinct_futures contains
- * a future for each possible set of side effects in the eclosure
- * of a given state.  This is some of the work of filling in a
- * superstate transition. 
- */
-
-#ifdef __STDC__
-static struct rx_distinct_future *include_futures(struct rx *rx, struct rx_distinct_future
-												  *df, struct rx_nfa_state
-												  *state, struct rx_superstate
-												  *superstate)
-#else
-static struct rx_distinct_future *include_futures(rx, df, state,
-												  superstate)
-struct rx *rx;
-struct rx_distinct_future *df;
-struct rx_nfa_state *state;
-struct rx_superstate *superstate;
-#endif
-{
-	struct rx_possible_future *future;
-	struct rx_cache *cache = rx->cache;
-
-	for (future = state->futures; future; future = future->next) {
-		struct rx_distinct_future *dfp;
-		struct rx_distinct_future *insert_before = 0;
-
-		if (df)
-			df->next_same_super_edge[1]->next_same_super_edge[0] = 0;
-		for (dfp = df; dfp; dfp = dfp->next_same_super_edge[0])
-			if (dfp->effects == future->effects)
-				break;
-			else {
-				int order =
-
-					rx->se_list_cmp(rx, dfp->effects, future->effects);
-				if (order > 0) {
-					insert_before = dfp;
-					dfp = 0;
-					break;
-				}
-			}
-		if (df)
-			df->next_same_super_edge[1]->next_same_super_edge[0] = df;
-		if (!dfp) {
-			dfp = ((struct rx_distinct_future *)
-				   rx_cache_malloc_or_get(cache,
-										  &cache->free_discernable_futures,
-
-										  sizeof(struct
-												 rx_distinct_future)));
-			if (!dfp)
-				return 0;
-			if (!df) {
-				df = insert_before = dfp;
-				df->next_same_super_edge[0] = df->next_same_super_edge[1] =
-					df;
-			} else if (!insert_before)
-				insert_before = df;
-			else if (insert_before == df)
-				df = dfp;
-
-			dfp->next_same_super_edge[0] = insert_before;
-			dfp->next_same_super_edge[1]
-				= insert_before->next_same_super_edge[1];
-			dfp->next_same_super_edge[1]->next_same_super_edge[0] = dfp;
-			dfp->next_same_super_edge[0]->next_same_super_edge[1] = dfp;
-			dfp->next_same_dest = dfp->prev_same_dest = dfp;
-			dfp->future = 0;
-			dfp->present = superstate;
-			dfp->future_frame.inx = rx->instruction_table[rx_cache_miss];
-			dfp->future_frame.data = 0;
-			dfp->future_frame.data_2 = (void *) dfp;
-			dfp->side_effects_frame.inx
-				= rx->instruction_table[rx_do_side_effects];
-			dfp->side_effects_frame.data = 0;
-			dfp->side_effects_frame.data_2 = (void *) dfp;
-			dfp->effects = future->effects;
-		}
-	}
-	return df;
-}
-
-
-/* This constructs a new superstate from its state set.  The only 
- * complexity here is memory management.
- */
-#ifdef __STDC__
-RX_DECL struct rx_superstate *rx_superstate(struct rx *rx,
-											struct rx_superset *set)
-#else
-RX_DECL struct rx_superstate *rx_superstate(rx, set)
-struct rx *rx;
-struct rx_superset *set;
-#endif
-{
-	struct rx_cache *cache = rx->cache;
-	struct rx_superstate *superstate = 0;
-
-	/* Does the superstate already exist in the cache? */
-	if (set->superstate) {
-		if (set->superstate->rx_id != rx->rx_id) {
-			/* Aha.  It is in the cache, but belongs to a superstate
-			 * that refers to an NFA that no longer exists.
-			 * (We know it no longer exists because it was evidently
-			 *  stored in the same region of memory as the current nfa
-			 *  yet it has a different id.)
-			 */
-			superstate = set->superstate;
-			if (!superstate->is_semifree) {
-				if (cache->lru_superstate == superstate) {
-					cache->lru_superstate = superstate->next_recyclable;
-					if (cache->lru_superstate == superstate)
-						cache->lru_superstate = 0;
-				}
-				{
-					superstate->next_recyclable->prev_recyclable
-						= superstate->prev_recyclable;
-					superstate->prev_recyclable->next_recyclable
-						= superstate->next_recyclable;
-					if (!cache->semifree_superstate) {
-						(cache->semifree_superstate
-						 = superstate->next_recyclable
-						 = superstate->prev_recyclable = superstate);
-					} else {
-						superstate->next_recyclable =
-							cache->semifree_superstate;
-						superstate->prev_recyclable =
-							cache->semifree_superstate->prev_recyclable;
-						superstate->next_recyclable->prev_recyclable =
-							superstate;
-						superstate->prev_recyclable->next_recyclable =
-							superstate;
-						cache->semifree_superstate = superstate;
-					}
-					++cache->semifree_superstates;
-				}
-			}
-			set->superstate = 0;
-			goto handle_cache_miss;
-		}
-		++cache->hits;
-		superstate = set->superstate;
-
-		rx_refresh_this_superstate(cache, superstate);
-		return superstate;
-	}
-
-  handle_cache_miss:
-
-	/* This point reached only for cache misses. */
-	++cache->misses;
-#if RX_DEBUG
-	if (rx_debug_trace > 1) {
-		struct rx_superset *setp = set;
-
-		fprintf(stderr, "Building a superstet %d(%d): ", rx->rx_id, set);
-		while (setp) {
-			fprintf(stderr, "%d ", setp->id);
-			setp = setp->cdr;
-		}
-		fprintf(stderr, "(%d)\n", set);
-	}
-#endif
-	superstate = (struct rx_superstate *) rx_cache_get_superstate(cache);
-	if (!superstate)
-		return 0;
-
-	if (!cache->lru_superstate)
-		(cache->lru_superstate
-		 = superstate->next_recyclable
-		 = superstate->prev_recyclable = superstate);
-	else {
-		superstate->next_recyclable = cache->lru_superstate;
-		superstate->prev_recyclable =
-			cache->lru_superstate->prev_recyclable;
-		(superstate->prev_recyclable->next_recyclable =
-		 superstate->next_recyclable->prev_recyclable = superstate);
-	}
-	superstate->rx_id = rx->rx_id;
-	superstate->transition_refs = 0;
-	superstate->locks = 0;
-	superstate->is_semifree = 0;
-	set->superstate = superstate;
-	superstate->contents = set;
-	rx_protect_superset(rx, set);
-	superstate->edges = 0;
-	{
-		int x;
-
-		/* None of the transitions from this superstate are known yet. */
-		for (x = 0; x < rx->local_cset_size; ++x) {	/* &&&&& 3.8 % */
-			struct rx_inx *ifr = &superstate->transitions[x];
-
-			ifr->inx = rx->instruction_table[rx_cache_miss];
-			ifr->data = ifr->data_2 = 0;
-		}
-	}
-	return superstate;
-}
-
-
-/* This computes the destination set of one edge of the superstate NFA.
- * Note that a RX_DISTINCT_FUTURE is a superstate edge.
- * Returns 0 on an allocation failure.
- */
-
-#ifdef __STDC__
-static int solve_destination(struct rx *rx, struct rx_distinct_future *df)
-#else
-static int solve_destination(rx, df)
-struct rx *rx;
-struct rx_distinct_future *df;
-#endif
-{
-	struct rx_super_edge *tc = df->edge;
-	struct rx_superset *nfa_state;
-	struct rx_superset *nil_set = rx_superset_cons(rx, 0, 0);
-	struct rx_superset *solution = nil_set;
-	struct rx_superstate *dest;
-
-	rx_protect_superset(rx, solution);
-	/* Iterate over all NFA states in the state set of this superstate. */
-	for (nfa_state = df->present->contents;
-		 nfa_state->car; nfa_state = nfa_state->cdr) {
-		struct rx_nfa_edge *e;
-
-		/* Iterate over all edges of each NFA state. */
-		for (e = nfa_state->car->edges; e; e = e->next)
-			/* If we find an edge that is labeled with 
-			   * the characters we are solving for.....
-			 */
-			if (rx_bitset_is_subset(rx->local_cset_size,
-									tc->cset, e->params.cset)) {
-				struct rx_nfa_state *n = e->dest;
-				struct rx_possible_future *pf;
-
-				/* ....search the partial epsilon closures of the destination
-				 * of that edge for a path that involves the same set of
-				 * side effects we are solving for.
-				 * If we find such a RX_POSSIBLE_FUTURE, we add members to the
-				 * stateset we are computing.
-				 */
-				for (pf = n->futures; pf; pf = pf->next)
-					if (pf->effects == df->effects) {
-						struct rx_superset *old_sol;
-
-						old_sol = solution;
-						solution =
-							rx_superstate_eclosure_union(rx, solution,
-														 pf->destset);
-						if (!solution)
-							return 0;
-						rx_protect_superset(rx, solution);
-						rx_release_superset(rx, old_sol);
-					}
-			}
-	}
-	/* It is possible that the RX_DISTINCT_FUTURE we are working on has 
-	 * the empty set of NFA states as its definition.  In that case, this
-	 * is a failure point.
-	 */
-	if (solution == nil_set) {
-		df->future_frame.inx = (void *) rx_backtrack;
-		df->future_frame.data = 0;
-		df->future_frame.data_2 = 0;
-		return 1;
-	}
-	dest = rx_superstate(rx, solution);
-	rx_release_superset(rx, solution);
-	if (!dest)
-		return 0;
-
-	{
-		struct rx_distinct_future *dft;
-
-		dft = df;
-		df->prev_same_dest->next_same_dest = 0;
-		while (dft) {
-			dft->future = dest;
-			dft->future_frame.inx = rx->instruction_table[rx_next_char];
-			dft->future_frame.data = (void *) dest->transitions;
-			dft = dft->next_same_dest;
-		}
-		df->prev_same_dest->next_same_dest = df;
-	}
-	if (!dest->transition_refs)
-		dest->transition_refs = df;
-	else {
-		struct rx_distinct_future *dft =
-
-			dest->transition_refs->next_same_dest;
-		dest->transition_refs->next_same_dest = df->next_same_dest;
-		df->next_same_dest->prev_same_dest = dest->transition_refs;
-		df->next_same_dest = dft;
-		dft->prev_same_dest = df;
-	}
-	return 1;
-}
-
-
-/* This takes a superstate and a character, and computes some edges
- * from the superstate NFA.  In particular, this computes all edges
- * that lead from SUPERSTATE given CHR.   This function also 
- * computes the set of characters that share this edge set.
- * This returns 0 on allocation error.
- * The character set and list of edges are returned through 
- * the paramters CSETOUT and DFOUT.
-} */
-
-#ifdef __STDC__
-static int
-compute_super_edge(struct rx *rx, struct rx_distinct_future **dfout,
-				   rx_Bitset csetout, struct rx_superstate *superstate,
-				   unsigned char chr)
-#else
-static int compute_super_edge(rx, dfout, csetout, superstate, chr)
-struct rx *rx;
-struct rx_distinct_future **dfout;
-rx_Bitset csetout;
-struct rx_superstate *superstate;
-unsigned char chr;
-#endif
-{
-	struct rx_superset *stateset = superstate->contents;
-
-	/* To compute the set of characters that share edges with CHR, 
-	 * we start with the full character set, and subtract.
-	 */
-	rx_bitset_universe(rx->local_cset_size, csetout);
-	*dfout = 0;
-
-	/* Iterate over the NFA states in the superstate state-set. */
-	while (stateset->car) {
-		struct rx_nfa_edge *e;
-
-		for (e = stateset->car->edges; e; e = e->next)
-			if (RX_bitset_member(e->params.cset, chr)) {
-				/* If we find an NFA edge that applies, we make sure there
-				 * are corresponding edges in the superstate NFA.
-				 */
-				{
-					struct rx_distinct_future *saved;
-
-					saved = *dfout;
-					*dfout =
-						include_futures(rx, *dfout, e->dest, superstate);
-					if (!*dfout) {
-						struct rx_distinct_future *df;
-
-						df = saved;
-						if (df)
-							df->
-								next_same_super_edge
-								[1]->next_same_super_edge[0] = 0;
-						while (df) {
-							struct rx_distinct_future *dft;
-
-							dft = df;
-							df = df->next_same_super_edge[0];
-
-							if (dft->future
-								&& dft->future->transition_refs == dft) {
-								dft->future->transition_refs =
-									dft->next_same_dest;
-								if (dft->future->transition_refs == dft)
-									dft->future->transition_refs = 0;
-							}
-							dft->next_same_dest->prev_same_dest =
-								dft->prev_same_dest;
-							dft->prev_same_dest->next_same_dest =
-								dft->next_same_dest;
-							rx_cache_free(rx->cache,
-										  &rx->
-										  cache->free_discernable_futures,
-										  (char *) dft);
-						}
-						return 0;
-					}
-				}
-				/* We also trim the character set a bit. */
-				rx_bitset_intersection(rx->local_cset_size,
-									   csetout, e->params.cset);
-			} else
-				/* An edge that doesn't apply at least tells us some characters
-				 * that don't share the same edge set as CHR.
-				 */
-				rx_bitset_difference(rx->local_cset_size, csetout,
-									 e->params.cset);
-		stateset = stateset->cdr;
-	}
-	return 1;
-}
-
-
-/* This is a constructor for RX_SUPER_EDGE structures.  These are
- * wrappers for lists of superstate NFA edges that share character sets labels.
- * If a transition class contains more than one rx_distinct_future (superstate
- * edge), then it represents a non-determinism in the superstate NFA.
- */
-
-
-#ifdef __STDC__
-static struct rx_super_edge *rx_super_edge(struct rx *rx,
-										   struct rx_superstate *super,
-										   rx_Bitset cset,
-										   struct rx_distinct_future *df)
-#else
-static struct rx_super_edge *rx_super_edge(rx, super, cset, df)
-struct rx *rx;
-struct rx_superstate *super;
-rx_Bitset cset;
-struct rx_distinct_future *df;
-#endif
-{
-	struct rx_super_edge *tc =
-		(struct rx_super_edge *) rx_cache_malloc_or_get
-		(rx->cache, &rx->cache->free_transition_classes,
-		 sizeof(struct rx_super_edge) +
-
-		 rx_sizeof_bitset(rx->local_cset_size));
-
-	if (!tc)
-		return 0;
-	tc->next = super->edges;
-	super->edges = tc;
-	tc->rx_backtrack_frame.inx = rx->instruction_table[rx_backtrack_point];
-	tc->rx_backtrack_frame.data = 0;
-	tc->rx_backtrack_frame.data_2 = (void *) tc;
-	tc->options = df;
-	tc->cset = (rx_Bitset) ((char *) tc + sizeof(*tc));
-	rx_bitset_assign(rx->local_cset_size, tc->cset, cset);
-	if (df) {
-		struct rx_distinct_future *dfp = df;
-
-		df->next_same_super_edge[1]->next_same_super_edge[0] = 0;
-		while (dfp) {
-			dfp->edge = tc;
-			dfp = dfp->next_same_super_edge[0];
-		}
-		df->next_same_super_edge[1]->next_same_super_edge[0] = df;
-	}
-	return tc;
-}
-
-
-/* There are three kinds of cache miss.  The first occurs when a
- * transition is taken that has never been computed during the
- * lifetime of the source superstate.  That cache miss is handled by
- * calling COMPUTE_SUPER_EDGE.  The second kind of cache miss
- * occurs when the destination superstate of a transition doesn't
- * exist.  SOLVE_DESTINATION is used to construct the destination superstate.
- * Finally, the third kind of cache miss occurs when the destination
- * superstate of a transition is in a `semi-free state'.  That case is
- * handled by UNFREE_SUPERSTATE.
- *
- * The function of HANDLE_CACHE_MISS is to figure out which of these
- * cases applies.
- */
-
-
-#ifdef __STDC__
-static void
-install_partial_transition(struct rx_superstate *super,
-						   struct rx_inx *answer,
-						   RX_subset set, int offset)
-#else
-static void install_partial_transition(super, answer, set, offset)
-struct rx_superstate *super;
-struct rx_inx *answer;
-RX_subset set;
-int offset;
-#endif
-{
-	int start = offset;
-	int end = start + 32;
-	RX_subset pos = 1;
-	struct rx_inx *transitions = super->transitions;
-
-	while (start < end) {
-		if (set & pos)
-			transitions[start] = *answer;
-		pos <<= 1;
-		++start;
-	}
-}
-
-#ifdef __STDC__
-RX_DECL struct rx_inx *rx_handle_cache_miss
-	(struct rx *rx, struct rx_superstate *super, unsigned char chr,
-	 void *data)
-#else
-RX_DECL struct rx_inx *rx_handle_cache_miss(rx, super, chr, data)
-struct rx *rx;
-struct rx_superstate *super;
-unsigned char chr;
-void *data;
-#endif
-{
-	int offset = chr / RX_subset_bits;
-	struct rx_distinct_future *df = data;
-
-	if (!df) {					/* must be the shared_cache_miss_frame */
-		/* Perhaps this is just a transition waiting to be filled. */
-		struct rx_super_edge *tc;
-		RX_subset mask = rx_subset_singletons[chr % RX_subset_bits];
-
-		for (tc = super->edges; tc; tc = tc->next)
-			if (tc->cset[offset] & mask) {
-				struct rx_inx *answer;
-
-				df = tc->options;
-				answer =
-					((tc->options->next_same_super_edge[0] !=
-					  tc->options) ? &tc->
-					 rx_backtrack_frame : (df->effects ?
-										   &df->side_effects_frame :
-										   &df->future_frame));
-				install_partial_transition(super, answer, tc->cset[offset],
-										   offset * 32);
-				return answer;
-			}
-		/* Otherwise, it's a flushed or  newly encountered edge. */
-		{
-			char cset_space[1024];	/* this limit is far from unreasonable */
-			rx_Bitset trcset;
-			struct rx_inx *answer;
-
-			if (rx_sizeof_bitset(rx->local_cset_size) > sizeof(cset_space))
-				return 0;		/* If the arbitrary limit is hit, always fail */
-			/* cleanly. */
-			trcset = (rx_Bitset) cset_space;
-			rx_lock_superstate(rx, super);
-			if (!compute_super_edge(rx, &df, trcset, super, chr)) {
-				rx_unlock_superstate(rx, super);
-				return 0;
-			}
-			if (!df) {			/* We just computed the fail transition. */
-				static struct rx_inx
-					shared_fail_frame = { 0, 0, (void *) rx_backtrack, 0 };
-
-				answer = &shared_fail_frame;
-			} else {
-				tc = rx_super_edge(rx, super, trcset, df);
-				if (!tc) {
-					rx_unlock_superstate(rx, super);
-					return 0;
-				}
-				answer =
-					((tc->options->next_same_super_edge[0] !=
-					  tc->options) ? &tc->
-					 rx_backtrack_frame : (df->effects ?
-										   &df->side_effects_frame :
-										   &df->future_frame));
-			}
-			install_partial_transition(super, answer,
-									   trcset[offset], offset * 32);
-			rx_unlock_superstate(rx, super);
-			return answer;
-		}
-	} else if (df->future) {	/* A cache miss on an edge with a future? Must be
-								   * a semi-free destination. */
-		if (df->future->is_semifree)
-			refresh_semifree_superstate(rx->cache, df->future);
-		return &df->future_frame;
-	} else
-		/* no future superstate on an existing edge */
-	{
-		rx_lock_superstate(rx, super);
-		if (!solve_destination(rx, df)) {
-			rx_unlock_superstate(rx, super);
-			return 0;
-		}
-		if (!df->effects
-			&& (df->edge->options->next_same_super_edge[0] ==
-				df->edge->options)) install_partial_transition(super,
-															   &df->future_frame,
-															   df->
-															   edge->cset
-															   [offset],
-															   offset *
-															   32);
-		rx_unlock_superstate(rx, super);
-		return &df->future_frame;
-	}
-}
-
-
-
-
-/* The rest of the code provides a regex.c compatable interface. */
-
-
-__const__ char *re_error_msg[] = {
-	0,							/* REG_NOUT */
-	"No match",					/* REG_NOMATCH */
-	"Invalid regular expression",	/* REG_BADPAT */
-	"Invalid collation character",	/* REG_ECOLLATE */
-	"Invalid character class name",	/* REG_ECTYPE */
-	"Trailing backslash",		/* REG_EESCAPE */
-	"Invalid back reference",	/* REG_ESUBREG */
-	"Unmatched [ or [^",		/* REG_EBRACK */
-	"Unmatched ( or \\(",		/* REG_EPAREN */
-	"Unmatched \\{",			/* REG_EBRACE */
-	"Invalid content of \\{\\}",	/* REG_BADBR */
-	"Invalid range end",		/* REG_ERANGE */
-	"Memory exhausted",			/* REG_ESPACE */
-	"Invalid preceding regular expression",	/* REG_BADRPT */
-	"Premature end of regular expression",	/* REG_EEND */
-	"Regular expression too big",	/* REG_ESIZE */
-	"Unmatched ) or \\)",		/* REG_ERPAREN */
-};
-
-
-
-/* 
- * Macros used while compiling patterns.
- *
- * By convention, PEND points just past the end of the uncompiled pattern,
- * P points to the read position in the pattern.  `translate' is the name
- * of the translation table (`TRANSLATE' is the name of a macro that looks
- * things up in `translate').
- */
-
-
-/*
- * Fetch the next character in the uncompiled pattern---translating it 
- * if necessary. *Also cast from a signed character in the constant
- * string passed to us by the user to an unsigned char that we can use
- * as an array index (in, e.g., `translate').
- */
-#define PATFETCH(c)							\
- do {if (p == pend) return REG_EEND;					\
-    c = (unsigned char) *p++;						\
-    c = translate[c];		 					\
- } while (0)
-
-/* 
- * Fetch the next character in the uncompiled pattern, with no
- * translation.
- */
-#define PATFETCH_RAW(c)							\
-  do {if (p == pend) return REG_EEND;					\
-    c = (unsigned char) *p++; 						\
-  } while (0)
-
-/* Go backwards one character in the pattern.  */
-#define PATUNFETCH p--
-
-
-#define TRANSLATE(d) translate[(unsigned char) (d)]
-
-typedef unsigned regnum_t;
-
-/* Since offsets can go either forwards or backwards, this type needs to
- * be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1.
- */
-typedef int pattern_offset_t;
-
-typedef struct {
-	struct rexp_node **top_expression;	/* was begalt */
-	struct rexp_node **last_expression;	/* was laststart */
-	pattern_offset_t inner_group_offset;
-	regnum_t regnum;
-} compile_stack_elt_t;
-typedef struct {
-	compile_stack_elt_t *stack;
-	unsigned size;
-	unsigned avail;				/* Offset of next open position.  */
-} compile_stack_type;
-
-static boolean group_in_compile_stack(compile_stack_type, regnum_t);
-static reg_errcode_t
-compile_range(struct re_pattern_buffer *, rx_Bitset,
-			  __const__ char **, __const__ char *,
-			  unsigned char *, reg_syntax_t, rx_Bitset, char *);
-static void find_backrefs(char *, struct rexp_node *,
-
-						  struct re_se_params *);
-static int compute_fastset(struct re_pattern_buffer *, struct rexp_node *);
-static int is_anchored(struct rexp_node *, rx_side_effect);
-static struct rexp_node
-*remove_unecessary_side_effects
-
-	(struct rx *, char *, struct rexp_node *, struct re_se_params *);
-static int pointless_if_repeated(struct rexp_node *,
-
-								 struct re_se_params *);
-static int registers_on_stack(struct re_pattern_buffer *,
-							  struct rexp_node *,
-
-							  int, struct re_se_params *);
-static int has_any_se(struct rx *, struct rexp_node *);
-static int has_non_idempotent_epsilon_path
-
-	(struct rx *, struct rexp_node *, struct re_se_params *);
-static int begins_with_complex_se(struct rx *, struct rexp_node *);
-static void speed_up_alt(struct rx *, struct rexp_node *, int);
-RX_DECL reg_errcode_t
-
-rx_compile(__const__ char *, int, reg_syntax_t,
-		   struct re_pattern_buffer *);
-RX_DECL void rx_blow_up_fastmap(struct re_pattern_buffer *);
-static __inline__ enum rx_get_burst_return
-re_search_2_get_burst(struct rx_string_position *, void *, int);
-static __inline__ enum rx_back_check_return
-re_search_2_back_check(struct rx_string_position *, int,
-					   int, unsigned char *, void *, int);
-static __inline__ int
-re_search_2_fetch_char(struct rx_string_position *, int, void *, int);
-
-
-#define INIT_COMPILE_STACK_SIZE 32
-
-#define COMPILE_STACK_EMPTY  (compile_stack.avail == 0)
-#define COMPILE_STACK_FULL  (compile_stack.avail == compile_stack.size)
-
-/* The next available element.  */
-#define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
-
-
-/* Set the bit for character C in a list.  */
-#define SET_LIST_BIT(c)                               \
-  (b[((unsigned char) (c)) / CHARBITS]               \
-   |= 1 << (((unsigned char) c) % CHARBITS))
-
-/* Get the next unsigned number in the uncompiled pattern.  */
-#define GET_UNSIGNED_NUMBER(num) 					\
-  { if (p != pend)							\
-     {									\
-       PATFETCH (c); 							\
-       while (isdigit (c)) 						\
-         { 								\
-           if (num < 0)							\
-              num = 0;							\
-           num = num * 10 + c - '0'; 					\
-           if (p == pend) 						\
-              break; 							\
-           PATFETCH (c);						\
-         } 								\
-       } 								\
-    }
-
-#define CHAR_CLASS_MAX_LENGTH  6	/* Namely, `xdigit'.  */
-
-#define IS_CHAR_CLASS(string)						\
-   (!strcmp (string, "alpha") || !strcmp (string, "upper")		\
-    || !strcmp (string, "lower") || !strcmp (string, "digit")		\
-    || !strcmp (string, "alnum") || !strcmp (string, "xdigit")		\
-    || !strcmp (string, "space") || !strcmp (string, "print")		\
-    || !strcmp (string, "punct") || !strcmp (string, "graph")		\
-    || !strcmp (string, "cntrl") || !strcmp (string, "blank"))
-
-
-/* These predicates are used in regex_compile. */
-
-/* P points to just after a ^ in PATTERN.  Return true if that ^ comes
- * after an alternative or a begin-subexpression.  We assume there is at
- * least one character before the ^.  
- */
-
-#ifdef __STDC__
-static boolean
-at_begline_loc_p(__const__ char *pattern, __const__ char *p,
-				 reg_syntax_t syntax)
-#else
-static boolean at_begline_loc_p(pattern, p, syntax)
-__const__ char *pattern;
-__const__ char *p;
-reg_syntax_t syntax;
-#endif
-{
-	__const__ char *prev = p - 2;
-	boolean prev_prev_backslash = ((prev > pattern) && (prev[-1] == '\\'));
-
-	return (					/* After a subexpression?  */
-			   ((*prev == '(') && ((syntax & RE_NO_BK_PARENS) || prev_prev_backslash))
-			   ||
-			   /* After an alternative?  */
-			   ((*prev == '|') && ((syntax & RE_NO_BK_VBAR) || prev_prev_backslash))
-		);
-}
-
-/* The dual of at_begline_loc_p.  This one is for $.  We assume there is
- * at least one character after the $, i.e., `P < PEND'.
- */
-
-#ifdef __STDC__
-static boolean
-at_endline_loc_p(__const__ char *p, __const__ char *pend, int syntax)
-#else
-static boolean at_endline_loc_p(p, pend, syntax)
-__const__ char *p;
-__const__ char *pend;
-int syntax;
-#endif
-{
-	__const__ char *next = p;
-	boolean next_backslash = (*next == '\\');
-	__const__ char *next_next = (p + 1 < pend) ? (p + 1) : 0;
-
-	return (
-			   /* Before a subexpression?  */
-			   ((syntax & RE_NO_BK_PARENS)
-				? (*next == ')')
-				: (next_backslash && next_next && (*next_next == ')')))
-			   ||
-			   /* Before an alternative?  */
-			   ((syntax & RE_NO_BK_VBAR)
-				? (*next == '|')
-				: (next_backslash && next_next && (*next_next == '|')))
-		);
-}
-
-
-unsigned char rx_id_translation[256] = {
-	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
-	10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
-	20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
-	30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
-	40, 41, 42, 43, 44, 45, 46, 47, 48, 49,
-	50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
-	60, 61, 62, 63, 64, 65, 66, 67, 68, 69,
-	70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
-	80, 81, 82, 83, 84, 85, 86, 87, 88, 89,
-	90, 91, 92, 93, 94, 95, 96, 97, 98, 99,
-
-	100, 101, 102, 103, 104, 105, 106, 107, 108, 109,
-	110, 111, 112, 113, 114, 115, 116, 117, 118, 119,
-	120, 121, 122, 123, 124, 125, 126, 127, 128, 129,
-	130, 131, 132, 133, 134, 135, 136, 137, 138, 139,
-	140, 141, 142, 143, 144, 145, 146, 147, 148, 149,
-	150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
-	160, 161, 162, 163, 164, 165, 166, 167, 168, 169,
-	170, 171, 172, 173, 174, 175, 176, 177, 178, 179,
-	180, 181, 182, 183, 184, 185, 186, 187, 188, 189,
-	190, 191, 192, 193, 194, 195, 196, 197, 198, 199,
-
-	200, 201, 202, 203, 204, 205, 206, 207, 208, 209,
-	210, 211, 212, 213, 214, 215, 216, 217, 218, 219,
-	220, 221, 222, 223, 224, 225, 226, 227, 228, 229,
-	230, 231, 232, 233, 234, 235, 236, 237, 238, 239,
-	240, 241, 242, 243, 244, 245, 246, 247, 248, 249,
-	250, 251, 252, 253, 254, 255
-};
-
-/* The compiler keeps an inverted translation table.
- * This looks up/inititalize elements.
- * VALID is an array of booleans that validate CACHE.
- */
-
-#ifdef __STDC__
-static rx_Bitset
-inverse_translation(struct re_pattern_buffer *rxb,
-					char *valid, rx_Bitset cache,
-					unsigned char *translate, int c)
-#else
-static rx_Bitset inverse_translation(rxb, valid, cache, translate, c)
-struct re_pattern_buffer *rxb;
-char *valid;
-rx_Bitset cache;
-unsigned char *translate;
-int c;
-#endif
-{
-	rx_Bitset cs
-
-		= cache + c * rx_bitset_numb_subsets(rxb->rx.local_cset_size);
-
-	if (!valid[c]) {
-		int x;
-		int c_tr = TRANSLATE(c);
-
-		rx_bitset_null(rxb->rx.local_cset_size, cs);
-		for (x = 0; x < 256; ++x)	/* &&&& 13.37 */
-			if (TRANSLATE(x) == c_tr)
-				RX_bitset_enjoin(cs, x);
-		valid[c] = 1;
-	}
-	return cs;
-}
-
-
-
-
-/* More subroutine declarations and macros for regex_compile.  */
-
-/* Returns true if REGNUM is in one of COMPILE_STACK's elements and 
-   false if it's not.  */
-
-#ifdef __STDC__
-static boolean
-group_in_compile_stack(compile_stack_type compile_stack, regnum_t regnum)
-#else
-static boolean group_in_compile_stack(compile_stack, regnum)
-compile_stack_type compile_stack;
-regnum_t regnum;
-#endif
-{
-	int this_element;
-
-	for (this_element = compile_stack.avail - 1;
-		 this_element >= 0; this_element--)
-		if (compile_stack.stack[this_element].regnum == regnum)
-			return true;
-
-	return false;
-}
-
-
-/*
- * Read the ending character of a range (in a bracket expression) from the
- * uncompiled pattern *P_PTR (which ends at PEND).  We assume the
- * starting character is in `P[-2]'.  (`P[-1]' is the character `-'.)
- * Then we set the translation of all bits between the starting and
- * ending characters (inclusive) in the compiled pattern B.
- * 
- * Return an error code.
- * 
- * We use these short variable names so we can use the same macros as
- * `regex_compile' itself.  
- */
-
-#ifdef __STDC__
-static reg_errcode_t
-compile_range(struct re_pattern_buffer *rxb, rx_Bitset cs,
-			  __const__ char **p_ptr, __const__ char *pend,
-			  unsigned char *translate, reg_syntax_t syntax,
-			  rx_Bitset inv_tr, char *valid_inv_tr)
-#else
-static reg_errcode_t
-compile_range(rxb, cs, p_ptr, pend, translate, syntax, inv_tr,
-			  valid_inv_tr)
-struct re_pattern_buffer *rxb;
-rx_Bitset cs;
-__const__ char **p_ptr;
-__const__ char *pend;
-unsigned char *translate;
-reg_syntax_t syntax;
-rx_Bitset inv_tr;
-char *valid_inv_tr;
-#endif
-{
-	unsigned this_char;
-
-	__const__ char *p = *p_ptr;
-
-	unsigned char range_end;
-	unsigned char range_start = TRANSLATE(p[-2]);
-
-	if (p == pend)
-		return REG_ERANGE;
-
-	PATFETCH(range_end);
-
-	(*p_ptr)++;
-
-	if (range_start > range_end)
-		return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
-
-	for (this_char = range_start; this_char <= range_end; this_char++) {
-		rx_Bitset it =
-			inverse_translation(rxb, valid_inv_tr, inv_tr, translate,
-
-								this_char);
-
-		rx_bitset_union(rxb->rx.local_cset_size, cs, it);
-	}
-
-	return REG_NOERROR;
-}
-
-
-/* This searches a regexp for backreference side effects.
- * It fills in the array OUT with 1 at the index of every register pair
- * referenced by a backreference.
- *
- * This is used to help optimize patterns for searching.  The information is
- * useful because, if the caller doesn't want register values, backreferenced
- * registers are the only registers for which we need rx_backtrack.
- */
-
-#ifdef __STDC__
-static void
-find_backrefs(char *out, struct rexp_node *rexp,
-			  struct re_se_params *params)
-#else
-static void find_backrefs(out, rexp, params)
-char *out;
-struct rexp_node *rexp;
-struct re_se_params *params;
-#endif
-{
-	if (rexp)
-		switch (rexp->type) {
-		case r_cset:
-		case r_data:
-			return;
-		case r_alternate:
-		case r_concat:
-		case r_opt:
-		case r_star:
-		case r_2phase_star:
-			find_backrefs(out, rexp->params.pair.left, params);
-			find_backrefs(out, rexp->params.pair.right, params);
-			return;
-		case r_side_effect:
-			if (((long) rexp->params.side_effect >= 0)
-				&& (params[(long) rexp->params.side_effect].se ==
-					re_se_backref))
-					out[params[(long) rexp->params.side_effect].op1] = 1;
-			return;
-		}
-}
-
-
-
-/* Returns 0 unless the pattern can match the empty string. */
-
-#ifdef __STDC__
-static int
-compute_fastset(struct re_pattern_buffer *rxb, struct rexp_node *rexp)
-#else
-static int compute_fastset(rxb, rexp)
-struct re_pattern_buffer *rxb;
-struct rexp_node *rexp;
-#endif
-{
-	if (!rexp)
-		return 1;
-	switch (rexp->type) {
-	case r_data:
-		return 1;
-	case r_cset:
-	{
-		rx_bitset_union(rxb->rx.local_cset_size,
-						rxb->fastset, rexp->params.cset);
-	}
-		return 0;
-	case r_concat:
-		return (compute_fastset(rxb, rexp->params.pair.left)
-				&& compute_fastset(rxb, rexp->params.pair.right));
-	case r_2phase_star:
-		compute_fastset(rxb, rexp->params.pair.left);
-		/* compute_fastset (rxb, rexp->params.pair.right);  nope... */
-		return 1;
-	case r_alternate:
-		return !!(compute_fastset(rxb, rexp->params.pair.left)
-				  + compute_fastset(rxb, rexp->params.pair.right));
-	case r_opt:
-	case r_star:
-		compute_fastset(rxb, rexp->params.pair.left);
-		return 1;
-	case r_side_effect:
-		return 1;
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-/* returns
- *  1 -- yes, definately anchored by the given side effect.
- *  2 -- maybe anchored, maybe the empty string.
- *  0 -- definately not anchored
- *  There is simply no other possibility.
- */
-
-#ifdef __STDC__
-static int is_anchored(struct rexp_node *rexp, rx_side_effect se)
-#else
-static int is_anchored(rexp, se)
-struct rexp_node *rexp;
-rx_side_effect se;
-#endif
-{
-	if (!rexp)
-		return 2;
-	switch (rexp->type) {
-	case r_cset:
-	case r_data:
-		return 0;
-	case r_concat:
-	case r_2phase_star:
-	{
-		int l = is_anchored(rexp->params.pair.left, se);
-
-		return (l == 2 ? is_anchored(rexp->params.pair.right, se) : l);
-	}
-	case r_alternate:
-	{
-		int l = is_anchored(rexp->params.pair.left, se);
-		int r = l ? is_anchored(rexp->params.pair.right, se) : 0;
-
-		if (l == r)
-			return l;
-		else if ((l == 0) || (r == 0))
-			return 0;
-		else
-			return 2;
-	}
-	case r_opt:
-	case r_star:
-		return is_anchored(rexp->params.pair.left, se) ? 2 : 0;
-
-	case r_side_effect:
-		return ((rexp->params.side_effect == se)
-				? 1 : 2);
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-/* This removes register assignments that aren't required by backreferencing.
- * This can speed up explore_future, especially if it eliminates
- * non-determinism in the superstate NFA.
- * 
- * NEEDED is an array of characters, presumably filled in by FIND_BACKREFS.
- * The non-zero elements of the array indicate which register assignments
- * can NOT be removed from the expression.
- */
-
-#ifdef __STDC__
-static struct rexp_node *remove_unecessary_side_effects(struct rx *rx,
-														char *needed,
-														struct rexp_node
-														*rexp,
-														struct re_se_params
-														*params)
-#else
-static struct rexp_node *remove_unecessary_side_effects(rx, needed, rexp,
-														params)
-struct rx *rx;
-char *needed;
-struct rexp_node *rexp;
-struct re_se_params *params;
-#endif
-{
-	struct rexp_node *l;
-	struct rexp_node *r;
-
-	if (!rexp)
-		return 0;
-	else
-		switch (rexp->type) {
-		case r_cset:
-		case r_data:
-			return rexp;
-		case r_alternate:
-		case r_concat:
-		case r_2phase_star:
-			l = remove_unecessary_side_effects(rx, needed,
-											   rexp->params.pair.left,
-											   params);
-			r =
-				remove_unecessary_side_effects(rx, needed,
-											   rexp->params.pair.right,
-											   params);
-			if ((l && r) || (rexp->type != r_concat)) {
-				rexp->params.pair.left = l;
-				rexp->params.pair.right = r;
-				return rexp;
-			} else {
-				rexp->params.pair.left = rexp->params.pair.right = 0;
-				rx_free_rexp(rx, rexp);
-				return l ? l : r;
-			}
-		case r_opt:
-		case r_star:
-			l = remove_unecessary_side_effects(rx, needed,
-											   rexp->params.pair.left,
-											   params);
-			if (l) {
-				rexp->params.pair.left = l;
-				return rexp;
-			} else {
-				rexp->params.pair.left = 0;
-				rx_free_rexp(rx, rexp);
-				return 0;
-			}
-		case r_side_effect:
-		{
-			int se = (long) rexp->params.side_effect;
-
-			if ((se >= 0)
-				&& (((enum re_side_effects) params[se].se == re_se_lparen)
-					|| ((enum re_side_effects) params[se].se ==
-						re_se_rparen)) && (params[se].op1 > 0)
-				&& (!needed[params[se].op1])) {
-				rx_free_rexp(rx, rexp);
-				return 0;
-			} else
-				return rexp;
-		}
-		}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-
-#ifdef __STDC__
-static int
-pointless_if_repeated(struct rexp_node *node, struct re_se_params *params)
-#else
-static int pointless_if_repeated(node, params)
-struct rexp_node *node;
-struct re_se_params *params;
-#endif
-{
-	if (!node)
-		return 1;
-	switch (node->type) {
-	case r_cset:
-		return 0;
-	case r_alternate:
-	case r_concat:
-	case r_2phase_star:
-		return (pointless_if_repeated(node->params.pair.left, params)
-				&& pointless_if_repeated(node->params.pair.right, params));
-	case r_opt:
-	case r_star:
-		return pointless_if_repeated(node->params.pair.left, params);
-	case r_side_effect:
-		switch (((long) node->params.side_effect < 0)
-				? (enum re_side_effects) node->params.side_effect
-				: (enum re_side_effects) params[(long) node->
-												params.side_effect].se) {
-		case re_se_try:
-		case re_se_at_dot:
-		case re_se_begbuf:
-		case re_se_hat:
-		case re_se_wordbeg:
-		case re_se_wordbound:
-		case re_se_notwordbound:
-		case re_se_wordend:
-		case re_se_endbuf:
-		case re_se_dollar:
-		case re_se_fail:
-		case re_se_win:
-			return 1;
-		case re_se_lparen:
-		case re_se_rparen:
-		case re_se_iter:
-		case re_se_end_iter:
-		case re_se_syntax:
-		case re_se_not_syntax:
-		case re_se_backref:
-			return 0;
-		}
-	case r_data:
-	default:
-		return 0;
-	}
-}
-
-
-
-#ifdef __STDC__
-static int
-registers_on_stack(struct re_pattern_buffer *rxb,
-				   struct rexp_node *rexp, int in_danger,
-				   struct re_se_params *params)
-#else
-static int registers_on_stack(rxb, rexp, in_danger, params)
-struct re_pattern_buffer *rxb;
-struct rexp_node *rexp;
-int in_danger;
-struct re_se_params *params;
-#endif
-{
-	if (!rexp)
-		return 0;
-	else
-		switch (rexp->type) {
-		case r_cset:
-		case r_data:
-			return 0;
-		case r_alternate:
-		case r_concat:
-			return (registers_on_stack(rxb, rexp->params.pair.left,
-									   in_danger, params)
-					|| (registers_on_stack
-						(rxb, rexp->params.pair.right,
-						 in_danger, params)));
-		case r_opt:
-			return registers_on_stack(rxb, rexp->params.pair.left, 0,
-									  params);
-		case r_star:
-			return registers_on_stack(rxb, rexp->params.pair.left, 1,
-									  params);
-		case r_2phase_star:
-			return
-				(registers_on_stack(rxb, rexp->params.pair.left, 1, params)
-				 || registers_on_stack(rxb, rexp->params.pair.right, 1,
-									   params));
-		case r_side_effect:
-		{
-			int se = (long) rexp->params.side_effect;
-
-			if (in_danger && (se >= 0)
-				&& (params[se].op1 > 0)
-				&& (((enum re_side_effects) params[se].se == re_se_lparen)
-					|| ((enum re_side_effects) params[se].se ==
-						re_se_rparen))) return 1;
-			else
-				return 0;
-		}
-		}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-
-static char idempotent_complex_se[] = {
-#define RX_WANT_SE_DEFS 1
-#undef RX_DEF_SE
-#undef RX_DEF_CPLX_SE
-#define RX_DEF_SE(IDEM, NAME, VALUE)
-#define RX_DEF_CPLX_SE(IDEM, NAME, VALUE)     IDEM,
-#include <regex.h>
-#undef RX_DEF_SE
-#undef RX_DEF_CPLX_SE
-#undef RX_WANT_SE_DEFS
-	23
-};
-
-static char idempotent_se[] = {
-	13,
-#define RX_WANT_SE_DEFS 1
-#undef RX_DEF_SE
-#undef RX_DEF_CPLX_SE
-#define RX_DEF_SE(IDEM, NAME, VALUE)	      IDEM,
-#define RX_DEF_CPLX_SE(IDEM, NAME, VALUE)
-#include <regex.h>
-#undef RX_DEF_SE
-#undef RX_DEF_CPLX_SE
-#undef RX_WANT_SE_DEFS
-	42
-};
-
-
-
-#ifdef __STDC__
-static int has_any_se(struct rx *rx, struct rexp_node *rexp)
-#else
-static int has_any_se(rx, rexp)
-struct rx *rx;
-struct rexp_node *rexp;
-#endif
-{
-	if (!rexp)
-		return 0;
-
-	switch (rexp->type) {
-	case r_cset:
-	case r_data:
-		return 0;
-
-	case r_side_effect:
-		return 1;
-
-	case r_2phase_star:
-	case r_concat:
-	case r_alternate:
-		return (has_any_se(rx, rexp->params.pair.left)
-				|| has_any_se(rx, rexp->params.pair.right));
-
-	case r_opt:
-	case r_star:
-		return has_any_se(rx, rexp->params.pair.left);
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-
-/* This must be called AFTER `convert_hard_loops' for a given REXP. */
-#ifdef __STDC__
-static int
-has_non_idempotent_epsilon_path(struct rx *rx,
-								struct rexp_node *rexp,
-								struct re_se_params *params)
-#else
-static int has_non_idempotent_epsilon_path(rx, rexp, params)
-struct rx *rx;
-struct rexp_node *rexp;
-struct re_se_params *params;
-#endif
-{
-	if (!rexp)
-		return 0;
-
-	switch (rexp->type) {
-	case r_cset:
-	case r_data:
-	case r_star:
-		return 0;
-
-	case r_side_effect:
-		return
-			!((long) rexp->params.side_effect > 0
-			  ?
-			  idempotent_complex_se[params
-									[(long) rexp->params.
-									 side_effect].se] :
-			  idempotent_se[-(long) rexp->params.side_effect]);
-
-	case r_alternate:
-		return
-			(has_non_idempotent_epsilon_path(rx,
-											 rexp->params.pair.left,
-											 params)
-			 || has_non_idempotent_epsilon_path(rx,
-												rexp->params.pair.right,
-												params));
-
-	case r_2phase_star:
-	case r_concat:
-		return
-			(has_non_idempotent_epsilon_path(rx,
-											 rexp->params.pair.left,
-											 params)
-			 && has_non_idempotent_epsilon_path(rx,
-												rexp->params.pair.right,
-												params));
-
-	case r_opt:
-		return has_non_idempotent_epsilon_path(rx,
-											   rexp->params.pair.left,
-											   params);
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-
-/* This computes rougly what it's name suggests.   It can (and does) go wrong 
- * in the direction of returning spurious 0 without causing disasters.
- */
-#ifdef __STDC__
-static int begins_with_complex_se(struct rx *rx, struct rexp_node *rexp)
-#else
-static int begins_with_complex_se(rx, rexp)
-struct rx *rx;
-struct rexp_node *rexp;
-#endif
-{
-	if (!rexp)
-		return 0;
-
-	switch (rexp->type) {
-	case r_cset:
-	case r_data:
-		return 0;
-
-	case r_side_effect:
-		return ((long) rexp->params.side_effect >= 0);
-
-	case r_alternate:
-		return (begins_with_complex_se(rx, rexp->params.pair.left)
-				&& begins_with_complex_se(rx, rexp->params.pair.right));
-
-
-	case r_concat:
-		return has_any_se(rx, rexp->params.pair.left);
-	case r_opt:
-	case r_star:
-	case r_2phase_star:
-		return 0;
-	}
-
-	/* this should never happen */
-	return 0;
-}
-
-
-/* This destructively removes some of the re_se_tv side effects from 
- * a rexp tree.  In particular, during parsing re_se_tv was inserted on the
- * right half of every | to guarantee that posix path preference could be 
- * honored.  This function removes some which it can be determined aren't 
- * needed.  
- */
-
-#ifdef __STDC__
-static void
-speed_up_alt(struct rx *rx, struct rexp_node *rexp, int unposix)
-#else
-static void speed_up_alt(rx, rexp, unposix)
-struct rx *rx;
-struct rexp_node *rexp;
-int unposix;
-#endif
-{
-	if (!rexp)
-		return;
-
-	switch (rexp->type) {
-	case r_cset:
-	case r_data:
-	case r_side_effect:
-		return;
-
-	case r_opt:
-	case r_star:
-		speed_up_alt(rx, rexp->params.pair.left, unposix);
-		return;
-
-	case r_2phase_star:
-	case r_concat:
-		speed_up_alt(rx, rexp->params.pair.left, unposix);
-		speed_up_alt(rx, rexp->params.pair.right, unposix);
-		return;
-
-	case r_alternate:
-		/* the right child is guaranteed to be (concat re_se_tv <subexp>) */
-
-		speed_up_alt(rx, rexp->params.pair.left, unposix);
-		speed_up_alt(rx, rexp->params.pair.right->params.pair.right,
-					 unposix);
-
-		if (unposix
-			|| (begins_with_complex_se
-				(rx, rexp->params.pair.right->params.pair.right))
-			|| !(has_any_se(rx, rexp->params.pair.right->params.pair.right)
-				 || has_any_se(rx, rexp->params.pair.left))) {
-			struct rexp_node *conc = rexp->params.pair.right;
-
-			rexp->params.pair.right = conc->params.pair.right;
-			conc->params.pair.right = 0;
-			rx_free_rexp(rx, conc);
-		}
-	}
-}
-
-
-
-
-
-/* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
-   Returns one of error codes defined in `regex.h', or zero for success.
-
-   Assumes the `allocated' (and perhaps `buffer') and `translate'
-   fields are set in BUFP on entry.
-
-   If it succeeds, results are put in BUFP (if it returns an error, the
-   contents of BUFP are undefined):
-     `buffer' is the compiled pattern;
-     `syntax' is set to SYNTAX;
-     `used' is set to the length of the compiled pattern;
-     `fastmap_accurate' is set to zero;
-     `re_nsub' is set to the number of groups in PATTERN;
-     `not_bol' and `not_eol' are set to zero.
-   
-   The `fastmap' and `newline_anchor' fields are neither
-   examined nor set.  */
-
-
-#ifdef __STDC__
-RX_DECL reg_errcode_t
-rx_compile(__const__ char *pattern, int size,
-		   reg_syntax_t syntax, struct re_pattern_buffer *rxb)
-#else
-RX_DECL reg_errcode_t rx_compile(pattern, size, syntax, rxb)
-__const__ char *pattern;
-int size;
-reg_syntax_t syntax;
-struct re_pattern_buffer *rxb;
-#endif
-{
-	RX_subset
-		inverse_translate[CHAR_SET_SIZE *
-						  rx_bitset_numb_subsets(CHAR_SET_SIZE)];
-	char validate_inv_tr[CHAR_SET_SIZE *
-
-						 rx_bitset_numb_subsets(CHAR_SET_SIZE)];
-
-	/* We fetch characters from PATTERN here.  Even though PATTERN is
-	   `char *' (i.e., signed), we declare these variables as unsigned, so
-	   they can be reliably used as array indices.  */
-	register unsigned char c, c1;
-
-	/* A random tempory spot in PATTERN.  */
-	__const__ char *p1;
-
-	/* Keeps track of unclosed groups.  */
-	compile_stack_type compile_stack;
-
-	/* Points to the current (ending) position in the pattern.  */
-	__const__ char *p = pattern;
-	__const__ char *pend = pattern + size;
-
-	/* How to translate the characters in the pattern.  */
-	unsigned char *translate = (rxb->translate
-
-								? rxb->translate : rx_id_translation);
-
-	/* When parsing is done, this will hold the expression tree. */
-	struct rexp_node *rexp = 0;
-
-	/* In the midst of compilation, this holds onto the regexp 
-	 * first parst while rexp goes on to aquire additional constructs.
-	 */
-	struct rexp_node *orig_rexp = 0;
-	struct rexp_node *fewer_side_effects = 0;
-
-	/* This and top_expression are saved on the compile stack. */
-	struct rexp_node **top_expression = &rexp;
-	struct rexp_node **last_expression = top_expression;
-
-	/* Parameter to `goto append_node' */
-	struct rexp_node *append;
-
-	/* Counts open-groups as they are encountered.  This is the index of the
-	 * innermost group being compiled.
-	 */
-	regnum_t regnum = 0;
-
-	/* Place in the uncompiled pattern (i.e., the {) to
-	 * which to go back if the interval is invalid.  
-	 */
-	__const__ char *beg_interval;
-
-	struct re_se_params *params = 0;
-	int paramc = 0;				/* How many complex side effects so far? */
-
-	rx_side_effect side;		/* param to `goto add_side_effect' */
-
-	bzero(validate_inv_tr, sizeof(validate_inv_tr));
-
-	rxb->rx.instruction_table = rx_id_instruction_table;
-
-
-	/* Initialize the compile stack.  */
-	compile_stack.stack = ((compile_stack_elt_t *)
-						   malloc((INIT_COMPILE_STACK_SIZE) *
-								  sizeof(compile_stack_elt_t)));
-	if (compile_stack.stack == 0)
-		return REG_ESPACE;
-
-	compile_stack.size = INIT_COMPILE_STACK_SIZE;
-	compile_stack.avail = 0;
-
-	/* Initialize the pattern buffer.  */
-	rxb->rx.cache = &default_cache;
-	rxb->syntax = syntax;
-	rxb->fastmap_accurate = 0;
-	rxb->not_bol = rxb->not_eol = 0;
-	rxb->least_subs = 0;
-
-	/* Always count groups, whether or not rxb->no_sub is set.  
-	 * The whole pattern is implicitly group 0, so counting begins
-	 * with 1.
-	 */
-	rxb->re_nsub = 0;
-
-#if !defined (emacs) && !defined (SYNTAX_TABLE)
-	/* Initialize the syntax table.  */
-	init_syntax_once();
-#endif
-
-	/* Loop through the uncompiled pattern until we're at the end.  */
-	while (p != pend) {
-		PATFETCH(c);
-
-		switch (c) {
-		case '^':
-		{
-			if (				/* If at start of pattern, it's an operator.  */
-				   p == pattern + 1
-				   /* If context independent, it's an operator.  */
-				   || syntax & RE_CONTEXT_INDEP_ANCHORS
-				   /* Otherwise, depends on what's come before.  */
-				   || at_begline_loc_p(pattern, p, syntax)) {
-				struct rexp_node *n = rx_mk_r_side_effect(&rxb->rx,
-														  (rx_side_effect) re_se_hat);
-
-				if (!n)
-					return REG_ESPACE;
-				append = n;
-				goto append_node;
-			} else
-				goto normal_char;
-		}
-			break;
-
-
-		case '$':
-		{
-			if (				/* If at end of pattern, it's an operator.  */
-				   p == pend
-				   /* If context independent, it's an operator.  */
-				   || syntax & RE_CONTEXT_INDEP_ANCHORS
-				   /* Otherwise, depends on what's next.  */
-				   || at_endline_loc_p(p, pend, syntax)) {
-				struct rexp_node *n = rx_mk_r_side_effect(&rxb->rx,
-														  (rx_side_effect) re_se_dollar);
-
-				if (!n)
-					return REG_ESPACE;
-				append = n;
-				goto append_node;
-			} else
-				goto normal_char;
-		}
-			break;
-
-
-		case '+':
-		case '?':
-			if ((syntax & RE_BK_PLUS_QM)
-				|| (syntax & RE_LIMITED_OPS))
-				goto normal_char;
-
-		  handle_plus:
-		case '*':
-			/* If there is no previous pattern... */
-			if (pointless_if_repeated(*last_expression, params)) {
-				if (syntax & RE_CONTEXT_INVALID_OPS)
-					return REG_BADRPT;
-				else if (!(syntax & RE_CONTEXT_INDEP_OPS))
-					goto normal_char;
-			}
-
-			{
-				/* 1 means zero (many) matches is allowed.  */
-				char zero_times_ok = 0, many_times_ok = 0;
-
-				/* If there is a sequence of repetition chars, collapse it
-				   down to just one (the right one).  We can't combine
-				   interval operators with these because of, e.g., `a{2}*',
-				   which should only match an even number of `a's.  */
-
-				for (;;) {
-					zero_times_ok |= c != '+';
-					many_times_ok |= c != '?';
-
-					if (p == pend)
-						break;
-
-					PATFETCH(c);
-
-					if (c == '*' || (!(syntax & RE_BK_PLUS_QM)
-									 && (c == '+' || c == '?')));
-
-					else if (syntax & RE_BK_PLUS_QM && c == '\\') {
-						if (p == pend)
-							return REG_EESCAPE;
-
-						PATFETCH(c1);
-						if (!(c1 == '+' || c1 == '?')) {
-							PATUNFETCH;
-							PATUNFETCH;
-							break;
-						}
-
-						c = c1;
-					} else {
-						PATUNFETCH;
-						break;
-					}
-
-					/* If we get here, we found another repeat character.  */
-				}
-
-				/* Star, etc. applied to an empty pattern is equivalent
-				   to an empty pattern.  */
-				if (!last_expression)
-					break;
-
-				/* Now we know whether or not zero matches is allowed
-				 * and also whether or not two or more matches is allowed.
-				 */
-
-				{
-					struct rexp_node *inner_exp = *last_expression;
-					int need_sync = 0;
-
-					if (many_times_ok
-						&& has_non_idempotent_epsilon_path(&rxb->rx,
-														   inner_exp,
-														   params)) {
-						struct rexp_node *pusher =
-							rx_mk_r_side_effect(&rxb->rx,
-												(rx_side_effect) re_se_pushpos);
-						struct rexp_node *checker
-							= rx_mk_r_side_effect(&rxb->rx,
-												  (rx_side_effect) re_se_chkpos);
-						struct rexp_node *pushback
-							= rx_mk_r_side_effect(&rxb->rx,
-												  (rx_side_effect) re_se_pushback);
-						rx_Bitset cs = rx_cset(&rxb->rx);
-						struct rexp_node *lit_t;
-						struct rexp_node *fake_state;
-						struct rexp_node *phase2;
-						struct rexp_node *popper;
-						struct rexp_node *star;
-						struct rexp_node *a;
-						struct rexp_node *whole_thing;
-
-						if (!cs)
-							return REG_ESPACE;
-						lit_t = rx_mk_r_cset(&rxb->rx, cs);
-						fake_state =
-							rx_mk_r_concat(&rxb->rx, pushback, lit_t);
-						phase2 =
-							rx_mk_r_concat(&rxb->rx, checker, fake_state);
-						popper =
-							rx_mk_r_side_effect(&rxb->rx,
-												(rx_side_effect)
-												re_se_poppos);
-						star =
-							rx_mk_r_2phase_star(&rxb->rx, inner_exp,
-												phase2);
-						a = rx_mk_r_concat(&rxb->rx, pusher, star);
-						whole_thing = rx_mk_r_concat(&rxb->rx, a, popper);
-
-						if (!
-							(pusher && star && pushback && lit_t
-							 && fake_state && lit_t && phase2 && checker
-							 && popper && a && whole_thing))
-							return REG_ESPACE;
-						RX_bitset_enjoin(cs, 't');
-						*last_expression = whole_thing;
-					} else {
-						struct rexp_node *star =
-							(many_times_ok ? rx_mk_r_star : rx_mk_r_opt)
-							(&rxb->rx, *last_expression);
-
-						if (!star)
-							return REG_ESPACE;
-						*last_expression = star;
-						need_sync = has_any_se(&rxb->rx, *last_expression);
-					}
-					if (!zero_times_ok) {
-						struct rexp_node *concat
-							= rx_mk_r_concat(&rxb->rx, inner_exp,
-											 rx_copy_rexp(&rxb->rx,
-														  *last_expression));
-
-						if (!concat)
-							return REG_ESPACE;
-						*last_expression = concat;
-					}
-					if (need_sync) {
-						int sync_se = paramc;
-
-						params = (params ? ((struct re_se_params *)
-											realloc(params,
-													sizeof(*params) * (1 +
-																	   paramc)))
-								  : ((struct re_se_params *)
-									 malloc(sizeof(*params))));
-						if (!params)
-							return REG_ESPACE;
-						++paramc;
-						params[sync_se].se = re_se_tv;
-						side = (rx_side_effect) sync_se;
-						goto add_side_effect;
-					}
-				}
-				/* The old regex.c used to optimize `.*\n'.  
-				 * Maybe rx should too?
-				 */
-			}
-			break;
-
-
-		case '.':
-		{
-			rx_Bitset cs = rx_cset(&rxb->rx);
-			struct rexp_node *n = rx_mk_r_cset(&rxb->rx, cs);
-
-			if (!(cs && n))
-				return REG_ESPACE;
-
-			rx_bitset_universe(rxb->rx.local_cset_size, cs);
-			if (!(rxb->syntax & RE_DOT_NEWLINE))
-				RX_bitset_remove(cs, '\n');
-			if (!(rxb->syntax & RE_DOT_NOT_NULL))
-				RX_bitset_remove(cs, 0);
-
-			append = n;
-			goto append_node;
-			break;
-		}
-
-
-		case '[':
-			if (p == pend)
-				return REG_EBRACK;
-			{
-				boolean had_char_class = false;
-				rx_Bitset cs = rx_cset(&rxb->rx);
-				struct rexp_node *node = rx_mk_r_cset(&rxb->rx, cs);
-				int is_inverted = *p == '^';
-
-				if (!(node && cs))
-					return REG_ESPACE;
-
-				/* This branch of the switch is normally exited with
-				 *`goto append_node'
-				 */
-				append = node;
-
-				if (is_inverted)
-					p++;
-
-				/* Remember the first position in the bracket expression.  */
-				p1 = p;
-
-				/* Read in characters and ranges, setting map bits.  */
-				for (;;) {
-					if (p == pend)
-						return REG_EBRACK;
-
-					PATFETCH(c);
-
-					/* \ might escape characters inside [...] and [^...].  */
-					if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS)
-						&& c == '\\') {
-						if (p == pend)
-							return REG_EESCAPE;
-
-						PATFETCH(c1);
-						{
-							rx_Bitset it = inverse_translation(rxb,
-															   validate_inv_tr,
-															   inverse_translate,
-															   translate,
-															   c1);
-
-							rx_bitset_union(rxb->rx.local_cset_size, cs,
-											it);
-						}
-						continue;
-					}
-
-					/* Could be the end of the bracket expression.  If it's
-					   not (i.e., when the bracket expression is `[]' so
-					   far), the ']' character bit gets set way below.  */
-					if (c == ']' && p != p1 + 1)
-						goto finalize_class_and_append;
-
-					/* Look ahead to see if it's a range when the last thing
-					   was a character class.  */
-					if (had_char_class && c == '-' && *p != ']')
-						return REG_ERANGE;
-
-					/* Look ahead to see if it's a range when the last thing
-					   was a character: if this is a hyphen not at the
-					   beginning or the end of a list, then it's the range
-					   operator.  */
-					if (c == '-' && !(p - 2 >= pattern && p[-2] == '[')
-						&& !(p - 3 >= pattern && p[-3] == '['
-							 && p[-2] == '^') && *p != ']') {
-						reg_errcode_t ret =
-							compile_range(rxb, cs, &p, pend, translate,
-										  syntax,
-										  inverse_translate,
-
-										  validate_inv_tr);
-
-						if (ret != REG_NOERROR)
-							return ret;
-					}
-
-					else if (p[0] == '-' && p[1] != ']') {	/* This handles ranges made up of characters only.  */
-						reg_errcode_t ret;
-
-						/* Move past the `-'.  */
-						PATFETCH(c1);
-
-						ret =
-							compile_range(rxb, cs, &p, pend, translate,
-										  syntax, inverse_translate,
-										  validate_inv_tr);
-						if (ret != REG_NOERROR)
-							return ret;
-					}
-
-					/* See if we're at the beginning of a possible character
-					   class.  */
-
-					else if ((syntax & RE_CHAR_CLASSES)
-							 && (c == '[') && (*p == ':')) {
-						char str[CHAR_CLASS_MAX_LENGTH + 1];
-
-						PATFETCH(c);
-						c1 = 0;
-
-						/* If pattern is `[[:'.  */
-						if (p == pend)
-							return REG_EBRACK;
-
-						for (;;) {
-							PATFETCH(c);
-							if (c == ':' || c == ']' || p == pend
-								|| c1 == CHAR_CLASS_MAX_LENGTH) break;
-							str[c1++] = c;
-						}
-						str[c1] = '\0';
-
-						/* If isn't a word bracketed by `[:' and:`]':
-						   undo the ending character, the letters, and leave 
-						   the leading `:' and `[' (but set bits for them).  */
-						if (c == ':' && *p == ']') {
-							int ch;
-							boolean is_alnum = !strcmp(str, "alnum");
-							boolean is_alpha = !strcmp(str, "alpha");
-							boolean is_blank = !strcmp(str, "blank");
-							boolean is_cntrl = !strcmp(str, "cntrl");
-							boolean is_digit = !strcmp(str, "digit");
-							boolean is_graph = !strcmp(str, "graph");
-							boolean is_lower = !strcmp(str, "lower");
-							boolean is_print = !strcmp(str, "print");
-							boolean is_punct = !strcmp(str, "punct");
-							boolean is_space = !strcmp(str, "space");
-							boolean is_upper = !strcmp(str, "upper");
-							boolean is_xdigit = !strcmp(str, "xdigit");
-
-							if (!IS_CHAR_CLASS(str))
-								return REG_ECTYPE;
-
-							/* Throw away the ] at the end of the character
-							   class.  */
-							PATFETCH(c);
-
-							if (p == pend)
-								return REG_EBRACK;
-
-							for (ch = 0; ch < 1 << CHARBITS; ch++) {
-								if ((is_alnum && isalnum(ch))
-									|| (is_alpha && isalpha(ch))
-									|| (is_blank && isblank(ch))
-									|| (is_cntrl && iscntrl(ch))
-									|| (is_digit && isdigit(ch))
-									|| (is_graph && isgraph(ch))
-									|| (is_lower && islower(ch))
-									|| (is_print && isprint(ch))
-									|| (is_punct && ispunct(ch))
-									|| (is_space && isspace(ch))
-									|| (is_upper && isupper(ch))
-									|| (is_xdigit && isxdigit(ch))) {
-									rx_Bitset it = inverse_translation(rxb,
-																	   validate_inv_tr,
-																	   inverse_translate,
-																	   translate,
-																	   ch);
-
-									rx_bitset_union(rxb->
-													rx.local_cset_size, cs,
-													it);
-								}
-							}
-							had_char_class = true;
-						} else {
-							c1++;
-							while (c1--)
-								PATUNFETCH;
-							{
-								rx_Bitset it = inverse_translation(rxb,
-																   validate_inv_tr,
-																   inverse_translate,
-																   translate,
-																   '[');
-
-								rx_bitset_union(rxb->rx.local_cset_size,
-												cs, it);
-							}
-							{
-								rx_Bitset it = inverse_translation(rxb,
-																   validate_inv_tr,
-																   inverse_translate,
-																   translate,
-																   ':');
-
-								rx_bitset_union(rxb->rx.local_cset_size,
-												cs, it);
-							}
-							had_char_class = false;
-						}
-					} else {
-						had_char_class = false;
-						{
-							rx_Bitset it = inverse_translation(rxb,
-															   validate_inv_tr,
-															   inverse_translate,
-															   translate,
-															   c);
-
-							rx_bitset_union(rxb->rx.local_cset_size, cs,
-											it);
-						}
-					}
-				}
-
-			  finalize_class_and_append:
-				if (is_inverted) {
-					rx_bitset_complement(rxb->rx.local_cset_size, cs);
-					if (syntax & RE_HAT_LISTS_NOT_NEWLINE)
-						RX_bitset_remove(cs, '\n');
-				}
-				goto append_node;
-			}
-			break;
-
-
-		case '(':
-			if (syntax & RE_NO_BK_PARENS)
-				goto handle_open;
-			else
-				goto normal_char;
-
-
-		case ')':
-			if (syntax & RE_NO_BK_PARENS)
-				goto handle_close;
-			else
-				goto normal_char;
-
-
-		case '\n':
-			if (syntax & RE_NEWLINE_ALT)
-				goto handle_alt;
-			else
-				goto normal_char;
-
-
-		case '|':
-			if (syntax & RE_NO_BK_VBAR)
-				goto handle_alt;
-			else
-				goto normal_char;
-
-
-		case '{':
-			if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
-				goto handle_interval;
-			else
-				goto normal_char;
-
-
-		case '\\':
-			if (p == pend)
-				return REG_EESCAPE;
-
-			/* Do not translate the character after the \, so that we can
-			   distinguish, e.g., \B from \b, even if we normally would
-			   translate, e.g., B to b.  */
-			PATFETCH_RAW(c);
-
-			switch (c) {
-			case '(':
-				if (syntax & RE_NO_BK_PARENS)
-					goto normal_backslash;
-
-			  handle_open:
-				rxb->re_nsub++;
-				regnum++;
-				if (COMPILE_STACK_FULL) {
-					((compile_stack.stack) =
-					 (compile_stack_elt_t *) realloc(compile_stack.stack,
-													 (compile_stack.size <<
-													  1) *
-													 sizeof
-													 (compile_stack_elt_t)));
-					if (compile_stack.stack == 0)
-						return REG_ESPACE;
-
-					compile_stack.size <<= 1;
-				}
-
-				if (*last_expression) {
-					struct rexp_node *concat
-						= rx_mk_r_concat(&rxb->rx, *last_expression, 0);
-
-					if (!concat)
-						return REG_ESPACE;
-					*last_expression = concat;
-					last_expression = &concat->params.pair.right;
-				}
-
-				/*
-				   * These are the values to restore when we hit end of this
-				   * group.  
-				 */
-				COMPILE_STACK_TOP.top_expression = top_expression;
-				COMPILE_STACK_TOP.last_expression = last_expression;
-				COMPILE_STACK_TOP.regnum = regnum;
-
-				compile_stack.avail++;
-
-				top_expression = last_expression;
-				break;
-
-
-			case ')':
-				if (syntax & RE_NO_BK_PARENS)
-					goto normal_backslash;
-
-			  handle_close:
-				/* See similar code for backslashed left paren above.  */
-				if (COMPILE_STACK_EMPTY) {
-					if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD) {
-						goto normal_char;
-					} else {
-						return REG_ERPAREN;
-					}
-				}
-
-				/* Since we just checked for an empty stack above, this
-				   ``can't happen''.  */
-
-				{
-					/* We don't just want to restore into `regnum', because
-					   later groups should continue to be numbered higher,
-					   as in `(ab)c(de)' -- the second group is #2.  */
-					regnum_t this_group_regnum;
-					struct rexp_node **inner = top_expression;
-
-					compile_stack.avail--;
-					top_expression = COMPILE_STACK_TOP.top_expression;
-					last_expression = COMPILE_STACK_TOP.last_expression;
-					this_group_regnum = COMPILE_STACK_TOP.regnum;
-					{
-						int left_se = paramc;
-						int right_se = paramc + 1;
-
-						params = (params ? ((struct re_se_params *)
-											realloc(params,
-													(paramc +
-													 2) *
-													sizeof(params[0])))
-								  : ((struct re_se_params *)
-									 malloc(2 * sizeof(params[0]))));
-						if (!params)
-							return REG_ESPACE;
-						paramc += 2;
-
-						params[left_se].se = re_se_lparen;
-						params[left_se].op1 = this_group_regnum;
-						params[right_se].se = re_se_rparen;
-						params[right_se].op1 = this_group_regnum;
-						{
-							struct rexp_node *left
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) left_se);
-							struct rexp_node *right
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) right_se);
-							struct rexp_node *c1
-								= (*inner ? rx_mk_r_concat(&rxb->rx, left,
-														   *inner) : left);
-							struct rexp_node *c2 =
-								rx_mk_r_concat(&rxb->rx, c1, right);
-
-							if (!(left && right && c1 && c2))
-								return REG_ESPACE;
-							*inner = c2;
-						}
-					}
-					break;
-				}
-
-			case '|':			/* `\|'.  */
-				if ((syntax & RE_LIMITED_OPS) || (syntax & RE_NO_BK_VBAR))
-					goto normal_backslash;
-			  handle_alt:
-				if (syntax & RE_LIMITED_OPS)
-					goto normal_char;
-
-				{
-					struct rexp_node *alt
-						= rx_mk_r_alternate(&rxb->rx, *top_expression, 0);
-
-					if (!alt)
-						return REG_ESPACE;
-					*top_expression = alt;
-					last_expression = &alt->params.pair.right;
-					{
-						int sync_se = paramc;
-
-						params = (params ? ((struct re_se_params *)
-											realloc(params,
-													(paramc +
-													 1) *
-													sizeof(params[0])))
-								  : ((struct re_se_params *)
-									 malloc(sizeof(params[0]))));
-						if (!params)
-							return REG_ESPACE;
-						++paramc;
-
-						params[sync_se].se = re_se_tv;
-						{
-							struct rexp_node *sync
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) sync_se);
-							struct rexp_node *conc
-								= rx_mk_r_concat(&rxb->rx, sync, 0);
-
-							if (!sync || !conc)
-								return REG_ESPACE;
-
-							*last_expression = conc;
-							last_expression = &conc->params.pair.right;
-						}
-					}
-				}
-				break;
-
-
-			case '{':
-				/* If \{ is a literal.  */
-				if (!(syntax & RE_INTERVALS)
-					/* If we're at `\{' and it's not the open-interval 
-					   operator.  */
-					|| ((syntax & RE_INTERVALS)
-						&& (syntax & RE_NO_BK_BRACES)) || (p - 2 == pattern
-														   && p == pend))
-					goto normal_backslash;
-
-			  handle_interval:
-				{
-					/* If got here, then the syntax allows intervals.  */
-
-					/* At least (most) this many matches must be made.  */
-					int lower_bound = -1, upper_bound = -1;
-
-					beg_interval = p - 1;
-
-					if (p == pend) {
-						if (syntax & RE_NO_BK_BRACES)
-							goto unfetch_interval;
-						else
-							return REG_EBRACE;
-					}
-
-					GET_UNSIGNED_NUMBER(lower_bound);
-
-					if (c == ',') {
-						GET_UNSIGNED_NUMBER(upper_bound);
-						if (upper_bound < 0)
-							upper_bound = RE_DUP_MAX;
-					} else
-						/* Interval such as `{1}' => match exactly once. */
-						upper_bound = lower_bound;
-
-					if (lower_bound < 0 || upper_bound > RE_DUP_MAX
-						|| lower_bound > upper_bound) {
-						if (syntax & RE_NO_BK_BRACES)
-							goto unfetch_interval;
-						else
-							return REG_BADBR;
-					}
-
-					if (!(syntax & RE_NO_BK_BRACES)) {
-						if (c != '\\')
-							return REG_EBRACE;
-						PATFETCH(c);
-					}
-
-					if (c != '}') {
-						if (syntax & RE_NO_BK_BRACES)
-							goto unfetch_interval;
-						else
-							return REG_BADBR;
-					}
-
-					/* We just parsed a valid interval.  */
-
-					/* If it's invalid to have no preceding re.  */
-					if (pointless_if_repeated(*last_expression, params)) {
-						if (syntax & RE_CONTEXT_INVALID_OPS)
-							return REG_BADRPT;
-						else if (!(syntax & RE_CONTEXT_INDEP_OPS))
-							goto unfetch_interval;
-						/* was: else laststart = b; */
-					}
-
-					/* If the upper bound is zero, don't want to iterate
-					 * at all.
-					 */
-					if (upper_bound == 0) {
-						if (*last_expression) {
-							rx_free_rexp(&rxb->rx, *last_expression);
-							*last_expression = 0;
-						}
-					} else
-						/* Otherwise, we have a nontrivial interval. */
-					{
-						int iter_se = paramc;
-						int end_se = paramc + 1;
-
-						params = (params ? ((struct re_se_params *)
-											realloc(params,
-													sizeof(*params) * (2 +
-																	   paramc)))
-								  : ((struct re_se_params *)
-									 malloc(2 * sizeof(*params))));
-						if (!params)
-							return REG_ESPACE;
-						paramc += 2;
-						params[iter_se].se = re_se_iter;
-						params[iter_se].op1 = lower_bound;
-						params[iter_se].op2 = upper_bound;
-
-						params[end_se].se = re_se_end_iter;
-						params[end_se].op1 = lower_bound;
-						params[end_se].op2 = upper_bound;
-						{
-							struct rexp_node *push0
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) re_se_push0);
-							struct rexp_node *start_one_iter
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) iter_se);
-							struct rexp_node *phase1
-								= rx_mk_r_concat(&rxb->rx, start_one_iter,
-												 *last_expression);
-							struct rexp_node *pushback
-								= rx_mk_r_side_effect(&rxb->rx,
-													  (rx_side_effect) re_se_pushback);
-							rx_Bitset cs = rx_cset(&rxb->rx);
-							struct rexp_node *lit_t;
-							struct rexp_node *phase2;
-							struct rexp_node *loop;
-							struct rexp_node *push_n_loop;
-							struct rexp_node *final_test;
-							struct rexp_node *full_exp;
-
-							if (!cs)
-								return REG_ESPACE;
-							lit_t = rx_mk_r_cset(&rxb->rx, cs);
-							phase2 =
-								rx_mk_r_concat(&rxb->rx, pushback, lit_t);
-							loop =
-								rx_mk_r_2phase_star(&rxb->rx, phase1,
-													phase2);
-							push_n_loop =
-								rx_mk_r_concat(&rxb->rx, push0, loop);
-							final_test =
-								rx_mk_r_side_effect(&rxb->rx,
-													(rx_side_effect)
-													end_se);
-							full_exp =
-								rx_mk_r_concat(&rxb->rx, push_n_loop,
-											   final_test);
-
-							if (!(push0 && start_one_iter && phase1
-								  && pushback && lit_t && phase2
-								  && loop && push_n_loop && final_test
-								  && full_exp)) return REG_ESPACE;
-
-							RX_bitset_enjoin(cs, 't');
-
-							*last_expression = full_exp;
-						}
-					}
-					beg_interval = 0;
-				}
-				break;
-
-			  unfetch_interval:
-				/* If an invalid interval, match the characters as literals.  */
-				p = beg_interval;
-				beg_interval = 0;
-
-				/* normal_char and normal_backslash need `c'.  */
-				PATFETCH(c);
-
-				if (!(syntax & RE_NO_BK_BRACES)) {
-					if (p > pattern && p[-1] == '\\')
-						goto normal_backslash;
-				}
-				goto normal_char;
-
-#ifdef emacs
-				/* There is no way to specify the before_dot and after_dot
-				   operators.  rms says this is ok.  --karl  */
-			case '=':
-				side = (rx_side_effect) rx_se_at_dot;
-				goto add_side_effect;
-				break;
-
-			case 's':
-			case 'S':
-			{
-				rx_Bitset cs = rx_cset(&rxb->rx);
-				struct rexp_node *set = rx_mk_r_cset(&rxb->rx, cs);
-
-				if (!(cs && set))
-					return REG_ESPACE;
-				if (c == 'S')
-					rx_bitset_universe(rxb->rx.local_cset_size, cs);
-
-				PATFETCH(c);
-				{
-					int x;
-					enum syntaxcode code = syntax_spec_code[c];
-
-					for (x = 0; x < 256; ++x) {
-
-						if (SYNTAX(x) == code) {
-							rx_Bitset it =
-								inverse_translation(rxb, validate_inv_tr,
-													inverse_translate,
-													translate, x);
-
-							rx_bitset_xor(rxb->rx.local_cset_size, cs, it);
-						}
-					}
-				}
-				append = set;
-				goto append_node;
-			}
-				break;
-#endif							/* emacs */
-
-
-			case 'w':
-			case 'W':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				{
-					rx_Bitset cs = rx_cset(&rxb->rx);
-					struct rexp_node *n =
-						(cs ? rx_mk_r_cset(&rxb->rx, cs) : 0);
-
-					if (!(cs && n))
-						return REG_ESPACE;
-					if (c == 'W')
-						rx_bitset_universe(rxb->rx.local_cset_size, cs);
-					{
-						int x;
-
-						for (x = rxb->rx.local_cset_size - 1; x > 0; --x)
-							if (SYNTAX(x) & Sword)
-								RX_bitset_toggle(cs, x);
-					}
-					append = n;
-					goto append_node;
-				}
-				break;
-
-/* With a little extra work, some of these side effects could be optimized
- * away (basicly by looking at what we already know about the surrounding
- * chars).  
- */
-			case '<':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_wordbeg;
-				goto add_side_effect;
-				break;
-
-			case '>':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_wordend;
-				goto add_side_effect;
-				break;
-
-			case 'b':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_wordbound;
-				goto add_side_effect;
-				break;
-
-			case 'B':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_notwordbound;
-				goto add_side_effect;
-				break;
-
-			case '`':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_begbuf;
-				goto add_side_effect;
-				break;
-
-			case '\'':
-				if (syntax & RE_NO_GNU_OPS)
-					goto normal_char;
-				side = (rx_side_effect) re_se_endbuf;
-				goto add_side_effect;
-				break;
-
-			  add_side_effect:
-				{
-					struct rexp_node *se
-
-						= rx_mk_r_side_effect(&rxb->rx, side);
-					if (!se)
-						return REG_ESPACE;
-					append = se;
-					goto append_node;
-				}
-				break;
-
-			case '1':
-			case '2':
-			case '3':
-			case '4':
-			case '5':
-			case '6':
-			case '7':
-			case '8':
-			case '9':
-				if (syntax & RE_NO_BK_REFS)
-					goto normal_char;
-
-				c1 = c - '0';
-
-				if (c1 > regnum)
-					return REG_ESUBREG;
-
-				/* Can't back reference to a subexpression if inside of it.  */
-				if (group_in_compile_stack(compile_stack, c1))
-					return REG_ESUBREG;
-
-				{
-					int backref_se = paramc;
-
-					params = (params ? ((struct re_se_params *)
-										realloc(params,
-												sizeof(*params) * (1 +
-																   paramc)))
-							  : ((struct re_se_params *)
-								 malloc(sizeof(*params))));
-					if (!params)
-						return REG_ESPACE;
-					++paramc;
-					params[backref_se].se = re_se_backref;
-					params[backref_se].op1 = c1;
-					side = (rx_side_effect) backref_se;
-					goto add_side_effect;
-				}
-				break;
-
-			case '+':
-			case '?':
-				if (syntax & RE_BK_PLUS_QM)
-					goto handle_plus;
-				else
-					goto normal_backslash;
-
-			default:
-			  normal_backslash:
-				/* You might think it would be useful for \ to mean
-				   not to translate; but if we don't translate it
-				   it will never match anything.  */
-				c = TRANSLATE(c);
-				goto normal_char;
-			}
-			break;
-
-
-		default:
-			/* Expects the character in `c'.  */
-		  normal_char:
-		{
-			rx_Bitset cs = rx_cset(&rxb->rx);
-			struct rexp_node *match = rx_mk_r_cset(&rxb->rx, cs);
-			rx_Bitset it;
-
-			if (!(cs && match))
-				return REG_ESPACE;
-			it = inverse_translation(rxb, validate_inv_tr,
-									 inverse_translate, translate, c);
-			rx_bitset_union(CHAR_SET_SIZE, cs, it);
-			append = match;
-
-		  append_node:
-			/* This genericly appends the rexp APPEND to *LAST_EXPRESSION
-			 * and then parses the next character normally.
-			 */
-			if (*last_expression) {
-				struct rexp_node *concat
-					= rx_mk_r_concat(&rxb->rx, *last_expression, append);
-
-				if (!concat)
-					return REG_ESPACE;
-				*last_expression = concat;
-				last_expression = &concat->params.pair.right;
-			} else
-				*last_expression = append;
-		}
-		}						/* switch (c) */
-	}							/* while p != pend */
-
-
-	{
-		int win_se = paramc;
-
-		params = (params ? ((struct re_se_params *)
-							realloc(params,
-									sizeof(*params) * (1 + paramc)))
-				  : ((struct re_se_params *)
-					 malloc(sizeof(*params))));
-		if (!params)
-			return REG_ESPACE;
-		++paramc;
-		params[win_se].se = re_se_win;
-		{
-			struct rexp_node *se
-				= rx_mk_r_side_effect(&rxb->rx, (rx_side_effect) win_se);
-			struct rexp_node *concat = rx_mk_r_concat(&rxb->rx, rexp, se);
-
-			if (!(se && concat))
-				return REG_ESPACE;
-			rexp = concat;
-		}
-	}
-
-
-	/* Through the pattern now.  */
-
-	if (!COMPILE_STACK_EMPTY)
-		return REG_EPAREN;
-
-	free(compile_stack.stack);
-
-	orig_rexp = rexp;
-#ifdef RX_DEBUG
-	if (rx_debug_compile) {
-		dbug_rxb = rxb;
-		fputs("\n\nCompiling ", stdout);
-		fwrite(pattern, 1, size, stdout);
-		fputs(":\n", stdout);
-		rxb->se_params = params;
-		print_rexp(&rxb->rx, orig_rexp, 2, re_seprint, stdout);
-	}
-#endif
-	{
-		rx_Bitset cs = rx_cset(&rxb->rx);
-		rx_Bitset cs2 = rx_cset(&rxb->rx);
-		char *se_map = (char *) alloca(paramc);
-		struct rexp_node *new_rexp = 0;
-
-
-		bzero(se_map, paramc);
-		find_backrefs(se_map, rexp, params);
-		fewer_side_effects =
-			remove_unecessary_side_effects(&rxb->rx, se_map,
-										   rx_copy_rexp(&rxb->rx, rexp),
-										   params);
-
-		speed_up_alt(&rxb->rx, rexp, 0);
-		speed_up_alt(&rxb->rx, fewer_side_effects, 1);
-
-		{
-			char *syntax_parens = rxb->syntax_parens;
-
-			if (syntax_parens == (char *) 0x1)
-				rexp = remove_unecessary_side_effects
-					(&rxb->rx, se_map, rexp, params);
-			else if (syntax_parens) {
-				int x;
-
-				for (x = 0; x < paramc; ++x)
-					if (((params[x].se == re_se_lparen)
-						 || (params[x].se == re_se_rparen))
-						&& (!syntax_parens[params[x].op1]))
-						se_map[x] = 1;
-				rexp = remove_unecessary_side_effects
-					(&rxb->rx, se_map, rexp, params);
-			}
-		}
-
-		/* At least one more optimization would be nice to have here but i ran out 
-		 * of time.  The idea would be to delay side effects.  
-		 * For examle, `(abc)' is the same thing as `abc()' except that the
-		 * left paren is offset by 3 (which we know at compile time).
-		 * (In this comment, write that second pattern `abc(:3:)' 
-		 * where `(:3:' is a syntactic unit.)
-		 *
-		 * Trickier:  `(abc|defg)'  is the same as `(abc(:3:|defg(:4:))'
-		 * (The paren nesting may be hard to follow -- that's an alternation
-		 *  of `abc(:3:' and `defg(:4:' inside (purely syntactic) parens
-		 *  followed by the closing paren from the original expression.)
-		 *
-		 * Neither the expression tree representation nor the the nfa make
-		 * this very easy to write. :(
-		 */
-
-		/* What we compile is different than what the parser returns.
-		 * Suppose the parser returns expression R.
-		 * Let R' be R with unnecessary register assignments removed 
-		 * (see REMOVE_UNECESSARY_SIDE_EFFECTS, above).
-		 *
-		 * What we will compile is the expression:
-		 *
-		 *    m{try}R{win}\|s{try}R'{win}
-		 *
-		 * {try} and {win} denote side effect epsilons (see EXPLORE_FUTURE).
-		 * 
-		 * When trying a match, we insert an `m' at the beginning of the 
-		 * string if the user wants registers to be filled, `s' if not.
-		 */
-		new_rexp =
-			rx_mk_r_alternate
-			(&rxb->rx,
-			 rx_mk_r_concat(&rxb->rx, rx_mk_r_cset(&rxb->rx, cs2), rexp),
-			 rx_mk_r_concat(&rxb->rx,
-							rx_mk_r_cset(&rxb->rx, cs),
-							fewer_side_effects));
-
-		if (!(new_rexp && cs && cs2))
-			return REG_ESPACE;
-		RX_bitset_enjoin(cs2, '\0');	/* prefixed to the rexp used for matching. */
-		RX_bitset_enjoin(cs, '\1');	/* prefixed to the rexp used for searching. */
-		rexp = new_rexp;
-	}
-
-#ifdef RX_DEBUG
-	if (rx_debug_compile) {
-		fputs("\n...which is compiled as:\n", stdout);
-		print_rexp(&rxb->rx, rexp, 2, re_seprint, stdout);
-	}
-#endif
-	{
-		struct rx_nfa_state *start = 0;
-		struct rx_nfa_state *end = 0;
-
-		if (!rx_build_nfa(&rxb->rx, rexp, &start, &end))
-			return REG_ESPACE;	/*  */
-		else {
-			void *mem = (void *) rxb->buffer;
-			unsigned long size = rxb->allocated;
-			int start_id;
-			char *perm_mem;
-			int iterator_size = paramc * sizeof(params[0]);
-
-			end->is_final = 1;
-			start->is_start = 1;
-			rx_name_nfa_states(&rxb->rx);
-			start_id = start->id;
-#ifdef RX_DEBUG
-			if (rx_debug_compile) {
-				fputs("...giving the NFA: \n", stdout);
-				dbug_rxb = rxb;
-				print_nfa(&rxb->rx, rxb->rx.nfa_states, re_seprint,
-						  stdout);
-			}
-#endif
-			if (!rx_eclose_nfa(&rxb->rx))
-				return REG_ESPACE;
-			else {
-				rx_delete_epsilon_transitions(&rxb->rx);
-
-				/* For compatability reasons, we need to shove the
-				 * compiled nfa into one chunk of malloced memory.
-				 */
-				rxb->rx.reserved = (sizeof(params[0]) * paramc
-									+
-									rx_sizeof_bitset(rxb->
-													 rx.local_cset_size));
-#ifdef RX_DEBUG
-				if (rx_debug_compile) {
-					dbug_rxb = rxb;
-					fputs("...which cooks down (uncompactified) to: \n",
-						  stdout);
-					print_nfa(&rxb->rx, rxb->rx.nfa_states, re_seprint,
-							  stdout);
-				}
-#endif
-				if (!rx_compactify_nfa(&rxb->rx, &mem, &size))
-					return REG_ESPACE;
-				rxb->buffer = mem;
-				rxb->allocated = size;
-				rxb->rx.buffer = mem;
-				rxb->rx.allocated = size;
-				perm_mem = ((char *) rxb->rx.buffer
-							+ rxb->rx.allocated - rxb->rx.reserved);
-				rxb->se_params = ((struct re_se_params *) perm_mem);
-				bcopy(params, rxb->se_params, iterator_size);
-				perm_mem += iterator_size;
-				rxb->fastset = (rx_Bitset) perm_mem;
-				rxb->start = rx_id_to_nfa_state(&rxb->rx, start_id);
-			}
-			rx_bitset_null(rxb->rx.local_cset_size, rxb->fastset);
-			rxb->can_match_empty = compute_fastset(rxb, orig_rexp);
-			rxb->match_regs_on_stack =
-				registers_on_stack(rxb, orig_rexp, 0, params);
-			rxb->search_regs_on_stack =
-				registers_on_stack(rxb, fewer_side_effects, 0, params);
-			if (rxb->can_match_empty)
-				rx_bitset_universe(rxb->rx.local_cset_size, rxb->fastset);
-			rxb->is_anchored =
-				is_anchored(orig_rexp, (rx_side_effect) re_se_hat);
-			rxb->begbuf_only =
-				is_anchored(orig_rexp, (rx_side_effect) re_se_begbuf);
-		}
-		rx_free_rexp(&rxb->rx, rexp);
-		if (params)
-			free(params);
-#ifdef RX_DEBUG
-		if (rx_debug_compile) {
-			dbug_rxb = rxb;
-			fputs("...which cooks down to: \n", stdout);
-			print_nfa(&rxb->rx, rxb->rx.nfa_states, re_seprint, stdout);
-		}
-#endif
-	}
-	return REG_NOERROR;
-}
-
-
-
-/* This table gives an error message for each of the error codes listed
-   in regex.h.  Obviously the order here has to be same as there.  */
-
-__const__ char *rx_error_msg[] = { 0,	/* REG_NOERROR */
-	"No match",					/* REG_NOMATCH */
-	"Invalid regular expression",	/* REG_BADPAT */
-	"Invalid collation character",	/* REG_ECOLLATE */
-	"Invalid character class name",	/* REG_ECTYPE */
-	"Trailing backslash",		/* REG_EESCAPE */
-	"Invalid back reference",	/* REG_ESUBREG */
-	"Unmatched [ or [^",		/* REG_EBRACK */
-	"Unmatched ( or \\(",		/* REG_EPAREN */
-	"Unmatched \\{",			/* REG_EBRACE */
-	"Invalid content of \\{\\}",	/* REG_BADBR */
-	"Invalid range end",		/* REG_ERANGE */
-	"Memory exhausted",			/* REG_ESPACE */
-	"Invalid preceding regular expression",	/* REG_BADRPT */
-	"Premature end of regular expression",	/* REG_EEND */
-	"Regular expression too big",	/* REG_ESIZE */
-	"Unmatched ) or \\)",		/* REG_ERPAREN */
-};
-
-
-
-
-char rx_slowmap[256] = {
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-};
-
-#ifdef __STDC__
-RX_DECL void rx_blow_up_fastmap(struct re_pattern_buffer *rxb)
-#else
-RX_DECL void rx_blow_up_fastmap(rxb)
-struct re_pattern_buffer *rxb;
-#endif
-{
-	int x;
-
-	for (x = 0; x < 256; ++x)	/* &&&& 3.6 % */
-		rxb->fastmap[x] = !!RX_bitset_member(rxb->fastset, x);
-	rxb->fastmap_accurate = 1;
-}
-
-
-
-
-#if !defined(REGEX_MALLOC) && !defined(__GNUC__)
-#define RE_SEARCH_2_FN	inner_re_search_2
-#define RE_S2_QUAL static
-#else
-#define RE_SEARCH_2_FN	re_search_2
-#define RE_S2_QUAL
-#endif
-
-struct re_search_2_closure {
-	__const__ char *string1;
-	int size1;
-	__const__ char *string2;
-	int size2;
-};
-
-RE_S2_QUAL int
-RE_SEARCH_2_FN(struct re_pattern_buffer *,
-			   __const__ char *,
-			   int, __const__ char *, int, int,
-
-			   int, struct re_registers *, int);
-int re_rx_search(struct re_pattern_buffer *, int,
-				 int, int, int, rx_get_burst_fn,
-				 rx_back_check_fn, rx_fetch_char_fn,
-				 void *, struct re_registers *,
-
-				 struct rx_search_state *, struct rx_search_state *);
-#if !defined(REGEX_MALLOC) && !defined(__GNUC__)
-int re_search_2(struct re_pattern_buffer *,
-				__const__ char *, int,
-				__const__ char *, int,
-
-				int, int, struct re_registers *, int);
-#endif
-int re_search(struct re_pattern_buffer *,
-
-			  __const__ char *, int, int, int, struct re_registers *);
-int re_match_2(struct re_pattern_buffer *,
-			   __const__ char *, int,
-			   __const__ char *, int, int, struct re_registers *, int);
-int re_match(struct re_pattern_buffer *,
-
-			 __const__ char *, int, int, struct re_registers *);
-reg_syntax_t re_set_syntax(reg_syntax_t);
-void re_set_registers(struct re_pattern_buffer *,
-					  struct re_registers *, unsigned,
-					  regoff_t *, regoff_t *);
-static int cplx_se_sublist_len(struct rx_se_list *);
-static int posix_se_list_order(struct rx *, struct rx_se_list *,
-
-							   struct rx_se_list *);
-__const__ char
-*re_compile_pattern(__const__ char *, int, struct re_pattern_buffer *);
-int re_compile_fastmap(struct re_pattern_buffer *);
-char *re_comp(__const__ char *);
-int re_exec(__const__ char *);
-int regcomp(regex_t *, __const__ char *, int);
-int regexec(__const__ regex_t *,
-			__const__ char *, size_t, regmatch_t pmatch[], int);
-size_t regerror(int, __const__ regex_t *, char *, size_t);
-
-#ifdef __STDC__
-static __inline__ enum rx_get_burst_return
-re_search_2_get_burst(struct rx_string_position *pos,
-					  void *vclosure, int stop)
-#else
-static __inline__ enum rx_get_burst_return
-re_search_2_get_burst(pos, vclosure, stop)
-struct rx_string_position *pos;
-void *vclosure;
-int stop;
-#endif
-{
-	struct re_search_2_closure *closure;
-
-	closure = (struct re_search_2_closure *) vclosure;
-	if (!closure->string2) {
-		int inset;
-
-		inset = pos->pos - pos->string;
-		if ((inset < -1) || (inset > closure->size1))
-			return rx_get_burst_no_more;
-		else {
-			pos->pos =
-				(__const__ unsigned char *) closure->string1 + inset;
-			pos->string = (__const__ unsigned char *) closure->string1;
-			pos->size = closure->size1;
-			pos->end = ((__const__ unsigned char *)
-						MIN(closure->string1 + closure->size1,
-							closure->string1 + stop));
-			pos->offset = 0;
-			return ((pos->pos < pos->end)
-					? rx_get_burst_ok : rx_get_burst_no_more);
-		}
-	} else if (!closure->string1) {
-		int inset;
-
-		inset = pos->pos - pos->string;
-		pos->pos = (__const__ unsigned char *) closure->string2 + inset;
-		pos->string = (__const__ unsigned char *) closure->string2;
-		pos->size = closure->size2;
-		pos->end = ((__const__ unsigned char *)
-					MIN(closure->string2 + closure->size2,
-						closure->string2 + stop));
-		pos->offset = 0;
-		return ((pos->pos < pos->end)
-				? rx_get_burst_ok : rx_get_burst_no_more);
-	} else {
-		int inset;
-
-		inset = pos->pos - pos->string + pos->offset;
-		if (inset < closure->size1) {
-			pos->pos =
-				(__const__ unsigned char *) closure->string1 + inset;
-			pos->string = (__const__ unsigned char *) closure->string1;
-			pos->size = closure->size1;
-			pos->end = ((__const__ unsigned char *)
-						MIN(closure->string1 + closure->size1,
-							closure->string1 + stop));
-			pos->offset = 0;
-			return rx_get_burst_ok;
-		} else {
-			pos->pos = ((__const__ unsigned char *)
-						closure->string2 + inset - closure->size1);
-			pos->string = (__const__ unsigned char *) closure->string2;
-			pos->size = closure->size2;
-			pos->end = ((__const__ unsigned char *)
-						MIN(closure->string2 + closure->size2,
-							closure->string2 + stop - closure->size1));
-			pos->offset = closure->size1;
-			return ((pos->pos < pos->end)
-					? rx_get_burst_ok : rx_get_burst_no_more);
-		}
-	}
-}
-
-
-#ifdef __STDC__
-static __inline__ enum rx_back_check_return
-re_search_2_back_check(struct rx_string_position *pos,
-					   int lparen, int rparen, unsigned char *translate,
-					   void *vclosure, int stop)
-#else
-static __inline__ enum rx_back_check_return
-re_search_2_back_check(pos, lparen, rparen, translate, vclosure, stop)
-struct rx_string_position *pos;
-int lparen;
-int rparen;
-unsigned char *translate;
-void *vclosure;
-int stop;
-#endif
-{
-	struct rx_string_position there;
-	struct rx_string_position past;
-
-	there = *pos;
-	there.pos = there.string + lparen - there.offset;
-	re_search_2_get_burst(&there, vclosure, stop);
-
-	past = *pos;
-	past.pos = past.string + rparen - there.offset;
-	re_search_2_get_burst(&past, vclosure, stop);
-
-	++pos->pos;
-	re_search_2_get_burst(pos, vclosure, stop);
-
-	while ((there.pos != past.pos)
-		   && (pos->pos != pos->end))
-		if (TRANSLATE(*there.pos) != TRANSLATE(*pos->pos))
-			return rx_back_check_fail;
-		else {
-			++there.pos;
-			++pos->pos;
-			if (there.pos == there.end)
-				re_search_2_get_burst(&there, vclosure, stop);
-			if (pos->pos == pos->end)
-				re_search_2_get_burst(pos, vclosure, stop);
-		}
-
-	if (there.pos != past.pos)
-		return rx_back_check_fail;
-	--pos->pos;
-	re_search_2_get_burst(pos, vclosure, stop);
-	return rx_back_check_pass;
-}
-
-#ifdef __STDC__
-static __inline__ int
-re_search_2_fetch_char(struct rx_string_position *pos, int offset,
-					   void *app_closure, int stop)
-#else
-static __inline__ int
-re_search_2_fetch_char(pos, offset, app_closure, stop)
-struct rx_string_position *pos;
-int offset;
-void *app_closure;
-int stop;
-#endif
-{
-	struct re_search_2_closure *closure;
-
-	closure = (struct re_search_2_closure *) app_closure;
-	if (offset == 0) {
-		if (pos->pos >= pos->string)
-			return *pos->pos;
-		else {
-			if (
-				(pos->string ==
-				 (__const__ unsigned char *) closure->string2)
-				&& (closure->string1) && (closure->size1))
-				return closure->string1[closure->size1 - 1];
-			else
-				return 0;		/* sure, why not. */
-		}
-	}
-	if (pos->pos == pos->end)
-		return *closure->string2;
-	else
-#if 0
-		return pos->pos[1];
-#else
-		return pos->pos[offset];	/* FIXME */
-#endif
-}
-
-#ifdef __STDC__
-RE_S2_QUAL int
-RE_SEARCH_2_FN(struct re_pattern_buffer *rxb,
-			   __const__ char *string1, int size1,
-			   __const__ char *string2, int size2,
-			   int startpos, int range,
-			   struct re_registers *regs, int stop)
-#else
-RE_S2_QUAL int
-RE_SEARCH_2_FN(rxb,
-			   string1, size1, string2, size2, startpos, range, regs, stop)
-struct re_pattern_buffer *rxb;
-__const__ char *string1;
-int size1;
-__const__ char *string2;
-int size2;
-int startpos;
-int range;
-struct re_registers *regs;
-int stop;
-#endif
-{
-	int answer;
-	struct re_search_2_closure closure;
-
-	closure.string1 = string1;
-	closure.size1 = size1;
-	closure.string2 = string2;
-	closure.size2 = size2;
-	answer = rx_search(rxb, startpos, range, stop, size1 + size2,
-					   re_search_2_get_burst,
-					   re_search_2_back_check,
-					   re_search_2_fetch_char,
-					   (void *) &closure, regs, 0, 0);
-	switch (answer) {
-	case rx_search_continuation:
-		abort();
-	case rx_search_error:
-		return -2;
-	case rx_search_soft_fail:
-	case rx_search_fail:
-		return -1;
-	default:
-		return answer;
-	}
-}
-
-/* Export rx_search to callers outside this file.  */
-
-#ifdef __STDC__
-int
-re_rx_search(struct re_pattern_buffer *rxb, int startpos, int range,
-			 int stop, int total_size, rx_get_burst_fn get_burst,
-			 rx_back_check_fn back_check, rx_fetch_char_fn fetch_char,
-			 void *app_closure, struct re_registers *regs,
-			 struct rx_search_state *resume_state,
-			 struct rx_search_state *save_state)
-#else
-int
-re_rx_search(rxb, startpos, range, stop, total_size,
-			 get_burst, back_check, fetch_char,
-			 app_closure, regs, resume_state, save_state)
-struct re_pattern_buffer *rxb;
-int startpos;
-int range;
-int stop;
-int total_size;
-rx_get_burst_fn get_burst;
-rx_back_check_fn back_check;
-rx_fetch_char_fn fetch_char;
-void *app_closure;
-struct re_registers *regs;
-struct rx_search_state *resume_state;
-struct rx_search_state *save_state;
-#endif
-{
-	return rx_search(rxb, startpos, range, stop, total_size,
-					 get_burst, back_check, fetch_char, app_closure,
-					 regs, resume_state, save_state);
-}
-
-#if !defined(REGEX_MALLOC) && !defined(__GNUC__)
-#ifdef __STDC__
-int
-re_search_2(struct re_pattern_buffer *rxb,
-			__const__ char *string1, int size1,
-			__const__ char *string2, int size2,
-			int startpos, int range, struct re_registers *regs, int stop)
-#else
-int
-re_search_2(rxb, string1, size1, string2, size2, startpos, range, regs,
-			stop)
-struct re_pattern_buffer *rxb;
-__const__ char *string1;
-int size1;
-__const__ char *string2;
-int size2;
-int startpos;
-int range;
-struct re_registers *regs;
-int stop;
-#endif
-{
-	int ret;
-
-	ret = inner_re_search_2(rxb, string1, size1, string2, size2, startpos,
-							range, regs, stop);
-	alloca(0);
-	return ret;
-}
-#endif
-
-
-/* Like re_search_2, above, but only one string is specified, and
- * doesn't let you say where to stop matching.
- */
-
-#ifdef __STDC__
-int
-re_search(struct re_pattern_buffer *rxb, __const__ char *string,
-		  int size, int startpos, int range, struct re_registers *regs)
-#else
-int re_search(rxb, string, size, startpos, range, regs)
-struct re_pattern_buffer *rxb;
-__const__ char *string;
-int size;
-int startpos;
-int range;
-struct re_registers *regs;
-#endif
-{
-	return re_search_2(rxb, 0, 0, string, size, startpos, range, regs,
-					   size);
-}
-
-#ifdef __STDC__
-int
-re_match_2(struct re_pattern_buffer *rxb,
-		   __const__ char *string1, int size1,
-		   __const__ char *string2, int size2,
-		   int pos, struct re_registers *regs, int stop)
-#else
-int re_match_2(rxb, string1, size1, string2, size2, pos, regs, stop)
-struct re_pattern_buffer *rxb;
-__const__ char *string1;
-int size1;
-__const__ char *string2;
-int size2;
-int pos;
-struct re_registers *regs;
-int stop;
-#endif
-{
-	struct re_registers some_regs;
-	regoff_t start;
-	regoff_t end;
-	int srch;
-	int save = rxb->regs_allocated;
-	struct re_registers *regs_to_pass = regs;
-	char *old_fastmap = rxb->fastmap;
-
-	if (!regs) {
-		some_regs.start = &start;
-		some_regs.end = &end;
-		some_regs.num_regs = 1;
-		regs_to_pass = &some_regs;
-		rxb->regs_allocated = REGS_FIXED;
-	}
-
-	rxb->fastmap = NULL;
-	srch = re_search_2(rxb, string1, size1, string2, size2,
-					   pos, 1, regs_to_pass, stop);
-	rxb->fastmap = old_fastmap;
-	if (regs_to_pass != regs)
-		rxb->regs_allocated = save;
-	if (srch < 0)
-		return srch;
-	return regs_to_pass->end[0] - regs_to_pass->start[0];
-}
-
-/* re_match is like re_match_2 except it takes only a single string.  */
-
-#ifdef __STDC__
-int
-re_match(struct re_pattern_buffer *rxb,
-		 __const__ char *string,
-		 int size, int pos, struct re_registers *regs)
-#else
-int re_match(rxb, string, size, pos, regs)
-struct re_pattern_buffer *rxb;
-__const__ char *string;
-int size;
-int pos;
-struct re_registers *regs;
-#endif
-{
-	return re_match_2(rxb, string, size, 0, 0, pos, regs, size);
-}
-
-
-
-/* Set by `re_set_syntax' to the current regexp syntax to recognize.  Can
-   also be assigned to arbitrarily: each pattern buffer stores its own
-   syntax, so it can be changed between regex compilations.  */
-reg_syntax_t re_syntax_options = RE_SYNTAX_EMACS;
-
-
-/* Specify the precise syntax of regexps for compilation.  This provides
-   for compatibility for various utilities which historically have
-   different, incompatible syntaxes.
-
-   The argument SYNTAX is a bit mask comprised of the various bits
-   defined in regex.h.  We return the old syntax.  */
-
-#ifdef __STDC__
-reg_syntax_t re_set_syntax(reg_syntax_t syntax)
-#else
-reg_syntax_t re_set_syntax(syntax)
-reg_syntax_t syntax;
-#endif
-{
-	reg_syntax_t ret = re_syntax_options;
-
-	re_syntax_options = syntax;
-	return ret;
-}
-
-
-/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
-   ENDS.  Subsequent matches using PATTERN_BUFFER and REGS will use
-   this memory for recording register information.  STARTS and ENDS
-   must be allocated using the malloc library routine, and must each
-   be at least NUM_REGS * sizeof (regoff_t) bytes long.
-
-   If NUM_REGS == 0, then subsequent matches should allocate their own
-   register data.
-
-   Unless this function is called, the first search or match using
-   PATTERN_BUFFER will allocate its own register data, without
-   freeing the old data.  */
-
-#ifdef __STDC__
-void
-re_set_registers(struct re_pattern_buffer *bufp,
-				 struct re_registers *regs,
-				 unsigned num_regs, regoff_t * starts, regoff_t * ends)
-#else
-void re_set_registers(bufp, regs, num_regs, starts, ends)
-struct re_pattern_buffer *bufp;
-struct re_registers *regs;
-unsigned num_regs;
-regoff_t *starts;
-regoff_t *ends;
-#endif
-{
-	if (num_regs) {
-		bufp->regs_allocated = REGS_REALLOCATE;
-		regs->num_regs = num_regs;
-		regs->start = starts;
-		regs->end = ends;
-	} else {
-		bufp->regs_allocated = REGS_UNALLOCATED;
-		regs->num_regs = 0;
-		regs->start = regs->end = (regoff_t) 0;
-	}
-}
-
-
-
-
-#ifdef __STDC__
-static int cplx_se_sublist_len(struct rx_se_list *list)
-#else
-static int cplx_se_sublist_len(list)
-struct rx_se_list *list;
-#endif
-{
-	int x = 0;
-
-	while (list) {
-		if ((long) list->car >= 0)
-			++x;
-		list = list->cdr;
-	}
-	return x;
-}
-
-
-/* For rx->se_list_cmp */
-
-#ifdef __STDC__
-static int
-posix_se_list_order(struct rx *rx,
-					struct rx_se_list *a, struct rx_se_list *b)
-#else
-static int posix_se_list_order(rx, a, b)
-struct rx *rx;
-struct rx_se_list *a;
-struct rx_se_list *b;
-#endif
-{
-	int al = cplx_se_sublist_len(a);
-	int bl = cplx_se_sublist_len(b);
-
-	if (!al && !bl)
-		return ((a == b)
-				? 0 : ((a < b) ? -1 : 1));
-
-	else if (!al)
-		return -1;
-
-	else if (!bl)
-		return 1;
-
-	else {
-		rx_side_effect *av = ((rx_side_effect *)
-							  alloca(sizeof(rx_side_effect) * (al + 1)));
-		rx_side_effect *bv = ((rx_side_effect *)
-							  alloca(sizeof(rx_side_effect) * (bl + 1)));
-		struct rx_se_list *ap = a;
-		struct rx_se_list *bp = b;
-		int ai, bi;
-
-		for (ai = al - 1; ai >= 0; --ai) {
-			while ((long) ap->car < 0)
-				ap = ap->cdr;
-			av[ai] = ap->car;
-			ap = ap->cdr;
-		}
-		av[al] = (rx_side_effect) - 2;
-		for (bi = bl - 1; bi >= 0; --bi) {
-			while ((long) bp->car < 0)
-				bp = bp->cdr;
-			bv[bi] = bp->car;
-			bp = bp->cdr;
-		}
-		bv[bl] = (rx_side_effect) - 1;
-
-		{
-			int ret;
-			int x = 0;
-
-			while (av[x] == bv[x])
-				++x;
-			ret = (((unsigned *) (av[x]) < (unsigned *) (bv[x])) ? -1 : 1);
-			return ret;
-		}
-	}
-}
-
-
-
-
-/* re_compile_pattern is the GNU regular expression compiler: it
-   compiles PATTERN (of length SIZE) and puts the result in RXB.
-   Returns 0 if the pattern was valid, otherwise an error string.
-
-   Assumes the `allocated' (and perhaps `buffer') and `translate' fields
-   are set in RXB on entry.
-
-   We call rx_compile to do the actual compilation.  */
-
-#ifdef __STDC__
-__const__ char *re_compile_pattern(__const__ char *pattern,
-								   int length,
-								   struct re_pattern_buffer *rxb)
-#else
-__const__ char *re_compile_pattern(pattern, length, rxb)
-__const__ char *pattern;
-int length;
-struct re_pattern_buffer *rxb;
-#endif
-{
-	reg_errcode_t ret;
-
-	/* GNU code is written to assume at least RE_NREGS registers will be set
-	   (and at least one extra will be -1).  */
-	rxb->regs_allocated = REGS_UNALLOCATED;
-
-	/* And GNU code determines whether or not to get register information
-	   by passing null for the REGS argument to re_match, etc., not by
-	   setting no_sub.  */
-	rxb->no_sub = 0;
-
-	rxb->rx.local_cset_size = 256;
-
-	/* Match anchors at newline.  */
-	rxb->newline_anchor = 1;
-
-	rxb->re_nsub = 0;
-	rxb->start = 0;
-	rxb->se_params = 0;
-	rxb->rx.nodec = 0;
-	rxb->rx.epsnodec = 0;
-	rxb->rx.instruction_table = 0;
-	rxb->rx.nfa_states = 0;
-	rxb->rx.se_list_cmp = posix_se_list_order;
-	rxb->rx.start_set = 0;
-
-	ret = rx_compile(pattern, length, re_syntax_options, rxb);
-	alloca(0);
-	return rx_error_msg[(int) ret];
-}
-
-
-#ifdef __STDC__
-int re_compile_fastmap(struct re_pattern_buffer *rxb)
-#else
-int re_compile_fastmap(rxb)
-struct re_pattern_buffer *rxb;
-#endif
-{
-	rx_blow_up_fastmap(rxb);
-	return 0;
-}
-
-
-
-
-/* Entry points compatible with 4.2 BSD regex library.  We don't define
-   them if this is an Emacs or POSIX compilation.  */
-
-#if (!defined (emacs) && !defined (_POSIX_SOURCE)) || defined(USE_BSD_REGEX)
-
-/* BSD has one and only one pattern buffer.  */
-static struct re_pattern_buffer rx_comp_buf;
-
-#ifdef __STDC__
-char *re_comp(__const__ char *s)
-#else
-char *re_comp(s)
-__const__ char *s;
-#endif
-{
-	reg_errcode_t ret;
-
-	if (!s || (*s == '\0')) {
-		if (!rx_comp_buf.buffer)
-			return "No previous regular expression";
-		return 0;
-	}
-
-	if (!rx_comp_buf.fastmap) {
-		rx_comp_buf.fastmap = (char *) malloc(1 << CHARBITS);
-		if (!rx_comp_buf.fastmap)
-			return "Memory exhausted";
-	}
-
-	/* Since `rx_exec' always passes NULL for the `regs' argument, we
-	   don't need to initialize the pattern buffer fields which affect it.  */
-
-	/* Match anchors at newlines.  */
-	rx_comp_buf.newline_anchor = 1;
-
-	rx_comp_buf.re_nsub = 0;
-	rx_comp_buf.start = 0;
-	rx_comp_buf.se_params = 0;
-	rx_comp_buf.rx.nodec = 0;
-	rx_comp_buf.rx.epsnodec = 0;
-	rx_comp_buf.rx.instruction_table = 0;
-	rx_comp_buf.rx.nfa_states = 0;
-	rx_comp_buf.rx.start = 0;
-	rx_comp_buf.rx.se_list_cmp = posix_se_list_order;
-	rx_comp_buf.rx.start_set = 0;
-	rx_comp_buf.rx.local_cset_size = 256;
-
-	ret = rx_compile(s, strlen(s), re_syntax_options, &rx_comp_buf);
-	alloca(0);
-
-	/* Yes, we're discarding `__const__' here.  */
-	return (char *) rx_error_msg[(int) ret];
-}
-
-
-#ifdef __STDC__
-int re_exec(__const__ char *s)
-#else
-int re_exec(s)
-__const__ char *s;
-#endif
-{
-	__const__ int len = strlen(s);
-
-	return
-		0 <= re_search(&rx_comp_buf, s, len, 0, len,
-					   (struct re_registers *) 0);
-}
-#endif							/* not emacs and not _POSIX_SOURCE */
-
-
-
-/* POSIX.2 functions.  Don't define these for Emacs.  */
-
-#if !defined(emacs)
-
-/* regcomp takes a regular expression as a string and compiles it.
-
-   PREG is a regex_t *.  We do not expect any fields to be initialized,
-   since POSIX says we shouldn't.  Thus, we set
-
-     `buffer' to the compiled pattern;
-     `used' to the length of the compiled pattern;
-     `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
-       REG_EXTENDED bit in CFLAGS is set; otherwise, to
-       RE_SYNTAX_POSIX_BASIC;
-     `newline_anchor' to REG_NEWLINE being set in CFLAGS;
-     `fastmap' and `fastmap_accurate' to zero;
-     `re_nsub' to the number of subexpressions in PATTERN.
-
-   PATTERN is the address of the pattern string.
-
-   CFLAGS is a series of bits which affect compilation.
-
-     If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
-     use POSIX basic syntax.
-
-     If REG_NEWLINE is set, then . and [^...] don't match newline.
-     Also, regexec will try a match beginning after every newline.
-
-     If REG_ICASE is set, then we considers upper- and lowercase
-     versions of letters to be equivalent when matching.
-
-     If REG_NOSUB is set, then when PREG is passed to regexec, that
-     routine will report only success or failure, and nothing about the
-     registers.
-
-   It returns 0 if it succeeds, nonzero if it doesn't.  (See regex.h for
-   the return codes and their meanings.)  */
-
-
-#ifdef __STDC__
-int regcomp(regex_t * preg, __const__ char *pattern, int cflags)
-#else
-int regcomp(preg, pattern, cflags)
-regex_t *preg;
-__const__ char *pattern;
-int cflags;
-#endif
-{
-	reg_errcode_t ret;
-	unsigned syntax
-
-		=
-		cflags & REG_EXTENDED ? RE_SYNTAX_POSIX_EXTENDED :
-		RE_SYNTAX_POSIX_BASIC;
-
-	/* regex_compile will allocate the space for the compiled pattern.  */
-	preg->buffer = 0;
-	preg->allocated = 0;
-	preg->fastmap = malloc(256);
-	if (!preg->fastmap)
-		return REG_ESPACE;
-	preg->fastmap_accurate = 0;
-
-	if (cflags & REG_ICASE) {
-		unsigned i;
-
-		preg->translate = (unsigned char *) malloc(256);
-		if (!preg->translate)
-			return (int) REG_ESPACE;
-
-		/* Map uppercase characters to corresponding lowercase ones.  */
-		for (i = 0; i < CHAR_SET_SIZE; i++)
-			preg->translate[i] = isupper(i) ? tolower(i) : i;
-	} else
-		preg->translate = 0;
-
-	/* If REG_NEWLINE is set, newlines are treated differently.  */
-	if (cflags & REG_NEWLINE) {	/* REG_NEWLINE implies neither . nor [^...] match newline.  */
-		syntax &= ~RE_DOT_NEWLINE;
-		syntax |= RE_HAT_LISTS_NOT_NEWLINE;
-		/* It also changes the matching behavior.  */
-		preg->newline_anchor = 1;
-	} else
-		preg->newline_anchor = 0;
-
-	preg->no_sub = !!(cflags & REG_NOSUB);
-
-	/* POSIX says a null character in the pattern terminates it, so we
-	   can use strlen here in compiling the pattern.  */
-	preg->re_nsub = 0;
-	preg->start = 0;
-	preg->se_params = 0;
-	preg->syntax_parens = 0;
-	preg->rx.nodec = 0;
-	preg->rx.epsnodec = 0;
-	preg->rx.instruction_table = 0;
-	preg->rx.nfa_states = 0;
-	preg->rx.local_cset_size = 256;
-	preg->rx.start = 0;
-	preg->rx.se_list_cmp = posix_se_list_order;
-	preg->rx.start_set = 0;
-	ret = rx_compile(pattern, strlen(pattern), syntax, preg);
-	alloca(0);
-
-	/* POSIX doesn't distinguish between an unmatched open-group and an
-	   unmatched close-group: both are REG_EPAREN.  */
-	if (ret == REG_ERPAREN)
-		ret = REG_EPAREN;
-
-	return (int) ret;
-}
-
-
-/* regexec searches for a given pattern, specified by PREG, in the
-   string STRING.
-
-   If NMATCH is zero or REG_NOSUB was set in the cflags argument to
-   `regcomp', we ignore PMATCH.  Otherwise, we assume PMATCH has at
-   least NMATCH elements, and we set them to the offsets of the
-   corresponding matched substrings.
-
-   EFLAGS specifies `execution flags' which affect matching: if
-   REG_NOTBOL is set, then ^ does not match at the beginning of the
-   string; if REG_NOTEOL is set, then $ does not match at the end.
-
-   We return 0 if we find a match and REG_NOMATCH if not.  */
-
-#ifdef __STDC__
-int
-regexec(__const__ regex_t * preg, __const__ char *string,
-		size_t nmatch, regmatch_t pmatch[], int eflags)
-#else
-int regexec(preg, string, nmatch, pmatch, eflags)
-__const__ regex_t *preg;
-__const__ char *string;
-size_t nmatch;
-regmatch_t pmatch[];
-int eflags;
-#endif
-{
-	int ret;
-	struct re_registers regs;
-	regex_t private_preg;
-	int len = strlen(string);
-	boolean want_reg_info = !preg->no_sub && nmatch > 0;
-
-	private_preg = *preg;
-
-	private_preg.not_bol = !!(eflags & REG_NOTBOL);
-	private_preg.not_eol = !!(eflags & REG_NOTEOL);
-
-	/* The user has told us exactly how many registers to return
-	 * information about, via `nmatch'.  We have to pass that on to the
-	 * matching routines.
-	 */
-	private_preg.regs_allocated = REGS_FIXED;
-
-	if (want_reg_info) {
-		regs.num_regs = nmatch;
-		regs.start = ((regoff_t *) malloc((nmatch) * sizeof(regoff_t)));
-		regs.end = ((regoff_t *) malloc((nmatch) * sizeof(regoff_t)));
-		if (regs.start == 0 || regs.end == 0)
-			return (int) REG_NOMATCH;
-	}
-
-	/* Perform the searching operation.  */
-	ret = re_search(&private_preg, string, len,
-					/* start: */ 0,
-					/* range: */ len,
-					want_reg_info ? &regs : (struct re_registers *) 0);
-
-	/* Copy the register information to the POSIX structure.  */
-	if (want_reg_info) {
-		if (ret >= 0) {
-			unsigned r;
-
-			for (r = 0; r < nmatch; r++) {
-				pmatch[r].rm_so = regs.start[r];
-				pmatch[r].rm_eo = regs.end[r];
-			}
-		}
-
-		/* If we needed the temporary register info, free the space now.  */
-		free(regs.start);
-		free(regs.end);
-	}
-
-	/* We want zero return to mean success, unlike `re_search'.  */
-	return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
-}
-
-
-/* Returns a message corresponding to an error code, ERRCODE, returned
-   from either regcomp or regexec.   */
-
-#ifdef __STDC__
-size_t
-regerror(int errcode, __const__ regex_t * preg,
-		 char *errbuf, size_t errbuf_size)
-#else
-size_t regerror(errcode, preg, errbuf, errbuf_size)
-int errcode;
-__const__ regex_t *preg;
-char *errbuf;
-size_t errbuf_size;
-#endif
-{
-	__const__ char *msg
-		= rx_error_msg[errcode] == 0 ? "Success" : rx_error_msg[errcode];
-	size_t msg_size = strlen(msg) + 1;	/* Includes the 0.  */
-
-	if (errbuf_size != 0) {
-		if (msg_size > errbuf_size) {
-			strncpy(errbuf, msg, errbuf_size - 1);
-			errbuf[errbuf_size - 1] = 0;
-		} else
-			strcpy(errbuf, msg);
-	}
-
-	return msg_size;
-}
-
-
-/* Free dynamically allocated space used by PREG.  */
-
-#ifdef __STDC__
-void regfree(regex_t * preg)
-#else
-void regfree(preg)
-regex_t *preg;
-#endif
-{
-	if (preg->buffer != 0)
-		free(preg->buffer);
-	preg->buffer = 0;
-	preg->allocated = 0;
-
-	if (preg->fastmap != 0)
-		free(preg->fastmap);
-	preg->fastmap = 0;
-	preg->fastmap_accurate = 0;
-
-	if (preg->translate != 0)
-		free(preg->translate);
-	preg->translate = 0;
-}
-
-#endif							/* not emacs  */