Make support for global constructors and global destructors be

configurable, so people who do not need or want ctor/dtor support
can disable it and make their binaries a little bit smaller.
 -Erik

4 files changed, 62 insertions, 12 deletions

diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in
index 089c1b40b..95c5ba7c2 100644
--- a/extra/Configs/Config.in
+++ b/extra/Configs/Config.in
@@ -60,6 +60,23 @@ config LDSO_LDD_SUPPORT
 	  application to function.  Disabling this option will makes uClibc's
 	  shared library loader a little bit smaller.  Most people will answer Y.
 
+config UCLIBC_CTOR_DTOR
+	bool "Support global constructors and destructos"
+	default y
+	help
+	  If you wish to build uClibc with support for global constructor
+	  (ctor) and global destructor (dtor) support, then answer Y here.
+	  When ctor/dtor support is enabled, binaries linked with uClibc must
+	  also be linked with crtbegin.o and crtend.o which are provided by gcc
+	  (the "*startfile:" and "*endfile:" settings in your gcc specs file
+	  may need to be adjusted to include these files).  This support will
+	  also add a small amount of additional size to each binary compiled vs
+	  uClibc.  If you will be using uClibc with C++, or if you need the gcc
+	  __attribute__((constructor)) and __attribute__((destructor)) to work,
+	  then you definately want to answer Y here.  If you don't need ctors
+	  or dtors and want your binaries to be as small as possible, then
+	  answer N.
+
 config UCLIBC_HAS_THREADS
 	bool "POSIX Threading Support"
 	default y
diff --git a/extra/gcc-uClibc/Makefile b/extra/gcc-uClibc/Makefile
index 677b10f3a..1c64f856a 100644
--- a/extra/gcc-uClibc/Makefile
+++ b/extra/gcc-uClibc/Makefile
@@ -1,7 +1,7 @@
 # Makefile for building a fake gcc/binutils toolchain
 # that simply spoofs the location of the C library
 #
-# Copyright (C) 2000,2001 Erik Andersen <andersen@uclibc.org>
+# Copyright (C) 2000-2002 Erik Andersen <andersen@uclibc.org>
 #
 
 TOPDIR = ../../
@@ -34,6 +34,11 @@ ifeq ($(strip $(HAS_ELF)),y)
 else
 	@echo "#undef __HAS_ELF__" >> gcc-uClibc.h
 endif
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+	@echo "#define __UCLIBC_CTOR_DTOR__ 1" >> gcc-uClibc.h
+else
+	@echo "#undef __UCLIBC_CTOR_DTOR__" >> gcc-uClibc.h
+endif
 
 gcc-uClibc: gcc-uClibc.h gcc-uClibc.c
 	$(NATIVE_CC) $(NATIVE_CFLAGS) -Wl,-s gcc-uClibc.c -o $(TARGET_ARCH)-uclibc-gcc
@@ -50,14 +55,16 @@ install: all
 	install -d $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin;
 	install -m 755 $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/
 	install -m 755 $(TARGET_ARCH)-uclibc-ld $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/
-	ln -fs $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-g++
-	ln -fs $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-c++
 	ln -fs $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-cc
-	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/c++
-	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/g++
 	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/gcc
 	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/cc
 	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-ld  $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/ld
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+	ln -fs $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-g++
+	ln -fs $(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-c++
+	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/c++
+	ln -fs $(SYSTEM_DEVEL_PREFIX)/bin/$(TARGET_ARCH)-uclibc-gcc $(PREFIX)$(DEVEL_TOOL_PREFIX)/bin/g++
+endif
 	for app in addr2line ar as cpp gasp nm objcopy \
 	    objdump ranlib size strings strip; do \
 	  APPNAME=`which $(CROSS)$${app}`; \
diff --git a/extra/gcc-uClibc/gcc-uClibc.c b/extra/gcc-uClibc/gcc-uClibc.c
index 8b7f53e7d..765521eae 100644
--- a/extra/gcc-uClibc/gcc-uClibc.c
+++ b/extra/gcc-uClibc/gcc-uClibc.c
@@ -83,10 +83,12 @@ static char *our_usr_lib_path = "-L"UCLIBC_DEVEL_PREFIX"/lib";
 
 static char static_linking[] = "-static";
 static char nostdinc[] = "-nostdinc";
-static char nostdinc_plus[] = "-nostdinc++";
 static char nostartfiles[] = "-nostartfiles";
 static char nodefaultlibs[] = "-nodefaultlibs";
 static char nostdlib[] = "-nostdlib";
+#ifdef __UCLIBC_CTOR_DTOR__
+static char nostdinc_plus[] = "-nostdinc++";
+#endif
 
 
 extern void *xmalloc(size_t size)
@@ -120,9 +122,8 @@ void xstrcat(char **string, ...)
 int main(int argc, char **argv)
 {
 	int use_build_dir = 0, linking = 1, use_static_linking = 0;
-	int use_stdinc = 1, use_nostdinc_plus = 0, use_start = 1, use_stdlib = 1, use_pic = 0;
+	int use_stdinc = 1, use_start = 1, use_stdlib = 1, use_pic = 0;
 	int source_count = 0, use_rpath = 0, verbose = 0;
-	int ctor_dtor = 1, cplusplus = 0;
 	int i, j, k, l, m, n;
 	char ** gcc_argv;
 	char ** gcc_argument;
@@ -141,15 +142,19 @@ int main(int argc, char **argv)
 	char *our_lib_path[2];
 	char *crt0_path[2];
 	const char *application_name;
+#ifdef __UCLIBC_CTOR_DTOR__
 	char *crti_path[2];
 	char *crtn_path[2];
-	char *GPLUSPLUS_BIN = NULL;
 	int len;
+	int ctor_dtor = 1, cplusplus = 0, use_nostdinc_plus = 0;
+	char *GPLUSPLUS_BIN = NULL;
+#endif
 
 	application_name = basename(argv[0]);
 	if (application_name[0] == '-')
 		application_name++;
 
+#ifdef __UCLIBC_CTOR_DTOR__
 	/* We must use strstr since g++ might be named like a
 	 * cross compiler (i.e. arm-linux-g++).   We must also
 	 * search carefully, in case we are searching something 
@@ -168,6 +173,7 @@ int main(int argc, char **argv)
 	    cplusplus = 1;
 	    use_nostdinc_plus = 1;
 	}
+#endif
 
 	devprefix = getenv("UCLIBC_DEVEL_PREFIX");
 	if (!devprefix) {
@@ -193,10 +199,12 @@ int main(int argc, char **argv)
 
 	xstrcat(&(crt0_path[0]), devprefix, "/lib/crt0.o", NULL);
 	xstrcat(&(crt0_path[1]), builddir, "/lib/crt0.o", NULL);
+#ifdef __UCLIBC_CTOR_DTOR__
 	xstrcat(&(crti_path[0]), devprefix, "/lib/crti.o", NULL);
 	xstrcat(&(crti_path[1]), builddir, "/lib/crti.o", NULL);
 	xstrcat(&(crtn_path[0]), devprefix, "/lib/crtn.o", NULL);
 	xstrcat(&(crtn_path[1]), builddir, "/lib/crtn.o", NULL);
+#endif
 
 	xstrcat(&(our_lib_path[0]), "-L", devprefix, "/lib", NULL);
 	xstrcat(&(our_lib_path[1]), "-L", builddir, "/lib", NULL);
@@ -267,11 +275,14 @@ int main(int argc, char **argv)
 					} else if (strcmp(nostdlib,argv[i]) == 0) {
 						use_start = 0;
 						use_stdlib = 0;
-					} else if (strcmp(nostdinc_plus,argv[i]) == 0) {
+					} 
+#ifdef __UCLIBC_CTOR_DTOR__
+					else if (strcmp(nostdinc_plus,argv[i]) == 0) {
 						if (cplusplus==1) {
 							use_nostdinc_plus = 0;
 						}
 					}
+#endif
 					break;
 				case 's':
 					if (strstr(argv[i],static_linking) != NULL) {
@@ -310,10 +321,13 @@ int main(int argc, char **argv)
 					} else if (strcmp("--uclibc-use-rpath",argv[i]) == 0) {
 					    use_rpath = 1;
 					    argv[i]='\0';
-					} else if (strcmp("--uclibc-no-ctors",argv[i]) == 0) {
+					}
+#ifdef __UCLIBC_CTOR_DTOR__
+					else if (strcmp("--uclibc-no-ctors",argv[i]) == 0) {
 					    ctor_dtor = 0;
 					    argv[i]='\0';
 					}
+#endif
 					break;
 			}
 		} else {				/* assume it is an existing source file */
@@ -325,9 +339,11 @@ int main(int argc, char **argv)
 	gcc_argument = __builtin_alloca(sizeof(char*) * (argc + 20));
 
 	i = 0; k = 0;
+#ifdef __UCLIBC_CTOR_DTOR__
 	if (cplusplus && GPLUSPLUS_BIN)
 	    gcc_argv[i++] = GPLUSPLUS_BIN;
 	else
+#endif
 	    gcc_argv[i++] = GCC_BIN;
 	
 	for ( j = 1 ; j < argc ; j++ ) {
@@ -370,6 +386,7 @@ int main(int argc, char **argv)
 	}
 	if (use_stdinc && source_count) {
 	    gcc_argv[i++] = nostdinc;
+#ifdef __UCLIBC_CTOR_DTOR__
 	    if (cplusplus) {
 		char *cppinc;
 		if (use_nostdinc_plus) {
@@ -382,6 +399,7 @@ int main(int argc, char **argv)
 		gcc_argv[i++] = "-isystem";
 		gcc_argv[i++] = cppinc;
 	    }
+#endif
 	    gcc_argv[i++] = "-isystem";
 	    gcc_argv[i++] = uClibc_inc[use_build_dir];
 	    gcc_argv[i++] = "-iwithprefix";
@@ -392,6 +410,7 @@ int main(int argc, char **argv)
 
 	if (linking && source_count) {
 	    if (use_start) {
+#ifdef __UCLIBC_CTOR_DTOR__
 		if (ctor_dtor) {
 		    gcc_argv[i++] = crti_path[use_build_dir];
 		    if (use_pic) {
@@ -400,6 +419,7 @@ int main(int argc, char **argv)
 			gcc_argv[i++] = LIBGCC_DIR "crtbegin.o" ;
 		    }
 		}
+#endif
 		gcc_argv[i++] = crt0_path[use_build_dir];
 	    }
 	    for ( l = 0 ; l < k ; l++ ) {
@@ -413,14 +433,17 @@ int main(int argc, char **argv)
 		if (libraries[l]) gcc_argv[i++] = libraries[l];
 	    }
 	    if (use_stdlib) {
+#ifdef __UCLIBC_CTOR_DTOR__
 		if (cplusplus) {
 		    gcc_argv[ i++ ] = "-lstdc++";
 		    gcc_argv[ i++ ] = "-lm";
 		}
+#endif
 		gcc_argv[i++] = "-lc";
 		gcc_argv[i++] = "-lgcc";
 		//gcc_argv[i++] = "-Wl,--end-group";
 	    }
+#ifdef __UCLIBC_CTOR_DTOR__
 	    if (ctor_dtor) {
 		if (use_pic) {
 		    gcc_argv[i++] = LIBGCC_DIR "crtendS.o" ;
@@ -429,6 +452,7 @@ int main(int argc, char **argv)
 		}
 		gcc_argv[i++] = crtn_path[use_build_dir];
 	    }
+#endif
 	} else {
 	    for ( l = 0 ; l < k ; l++ ) {
 		if (gcc_argument[l]) gcc_argv[i++] = gcc_argument[l];
@@ -443,8 +467,10 @@ int main(int argc, char **argv)
 		fflush(stdout);
 	}
 	//no need to free memory from xstrcat because we never return... 
+#ifdef __UCLIBC_CTOR_DTOR__
 	if (cplusplus && GPLUSPLUS_BIN)
 	    return execvp(GPLUSPLUS_BIN, gcc_argv);
 	else
+#endif
 	    return execvp(GCC_BIN, gcc_argv);
 }
diff --git a/extra/scripts/get-needed-libgcc-objects.sh b/extra/scripts/get-needed-libgcc-objects.sh
index 588634c8d..04e6737f9 100755
--- a/extra/scripts/get-needed-libgcc-objects.sh
+++ b/extra/scripts/get-needed-libgcc-objects.sh
@@ -18,7 +18,7 @@
 echo Finding missing symbols in libc.a ...
 echo "    partial linking..."
 rm -f libc.ldr
-$LD $LDFLAGS -r -o libc.ldr ../../lib/crt0.o ../../lib/crti.o ../../lib/crtn.o --whole-archive ../libc.a
+$LD $LDFLAGS -r -o libc.ldr $CRTOBJS --whole-archive ../libc.a
 
 if $NM --undefined-only libc.ldr 2>&1 | grep -v "^main$" | grep -v "^_GLOBAL_OFFSET_TABLE_$" | grep -v "_gp_disp" > sym.need ; then
     EXIT_WITH_ERROR=0