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authorEric Andersen <andersen@codepoet.org>2002-11-27 23:34:07 +0000
committerEric Andersen <andersen@codepoet.org>2002-11-27 23:34:07 +0000
commitae35d725cf586347b2adb1a6fe4216e70fce16cf (patch)
tree9fcdb86297695c3324e386e483e85db53133b412
parent44c91e654102116f99f80635c483db49126730e8 (diff)
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
-rw-r--r--extra/Configs/Config.in17
-rw-r--r--extra/gcc-uClibc/Makefile17
-rw-r--r--extra/gcc-uClibc/gcc-uClibc.c38
-rwxr-xr-xextra/scripts/get-needed-libgcc-objects.sh2
-rw-r--r--libc/Makefile9
-rw-r--r--libc/sysdeps/linux/arm/crt0.S4
-rw-r--r--libc/sysdeps/linux/common/Makefile15
-rw-r--r--libc/sysdeps/linux/i386/crt0.S9
-rw-r--r--libc/sysdeps/linux/mips/crt0.S4
-rw-r--r--libc/sysdeps/linux/sh/crt0.S38
-rw-r--r--libpthread/Makefile2
11 files changed, 132 insertions, 23 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
diff --git a/libc/Makefile b/libc/Makefile
index 595f69e4a..4a5110f0e 100644
--- a/libc/Makefile
+++ b/libc/Makefile
@@ -30,6 +30,12 @@
TOPDIR=../
include $(TOPDIR)Rules.mak
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+CRTOBJS="../../lib/crti.o ../../lib/crt0.o ../../lib/crtn.o"
+else
+CRTOBJS="../../lib/crt0.o"
+endif
+
DIRS = misc pwd_grp stdio string termios inet signal stdlib sysdeps unistd
# Check if the target architecture has a version script for
@@ -49,7 +55,8 @@ shared: $(TOPDIR)lib/$(LIBNAME)
@rm -rf tmp
@mkdir tmp
$(AR) rv ./tmp/libgcc-need.a
- @(cd tmp && CC=$(CC) LD=$(LD) LDFLAGS=$(CPU_LDFLAGS-y) NM=$(NM) AR=$(AR) LIBGCC=$(LIBGCC) \
+ @(cd tmp && CC=$(CC) LD=$(LD) LDFLAGS=$(CPU_LDFLAGS-y) NM=$(NM) AR=$(AR) \
+ LIBGCC=$(LIBGCC) CRTOBJS=$(CRTOBJS) \
/bin/sh $(TOPDIR)../extra/scripts/get-needed-libgcc-objects.sh)
$(LD) $(LDFLAGS) $(VERSION_SCRIPT) -soname=$(SHARED_MAJORNAME) -o $(SHARED_FULLNAME) \
--whole-archive ./tmp/libgcc-need.a $(LIBNAME) --no-whole-archive \
diff --git a/libc/sysdeps/linux/arm/crt0.S b/libc/sysdeps/linux/arm/crt0.S
index ad4865cc1..a930ff3f2 100644
--- a/libc/sysdeps/linux/arm/crt0.S
+++ b/libc/sysdeps/linux/arm/crt0.S
@@ -80,6 +80,7 @@ _start:
ldr r2,[sp, #8]
#endif
+#ifdef __UCLIBC_CTOR_DTOR__
/* Store the address of _init in r3 as an argument to main() */
ldr r3, =_init
@@ -89,6 +90,9 @@ _start:
/* Ok, now run uClibc's main() -- shouldn't return */
bl __uClibc_start_main
+#else
+ bl __uClibc_main
+#endif
/* Crash if somehow `exit' returns anyways. */
bl abort
diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile
index f66c09f31..8e0ed9485 100644
--- a/libc/sysdeps/linux/common/Makefile
+++ b/libc/sysdeps/linux/common/Makefile
@@ -24,11 +24,6 @@
TOPDIR=../../../../
include $(TOPDIR)Rules.mak
-SAFECFLAGS=$(WARNINGS) $(CPU_CFLAGS-y) $(OPTIMIZATION) -fno-builtin
-ifeq ($(strip $(DOPIC)),y)
-SAFECFLAGS+=-fPIC
-endif
-
CSRC= waitpid.c getdnnm.c gethstnm.c getcwd.c \
mkfifo.c setegid.c wait.c getpagesize.c seteuid.c \
wait3.c setpgrp.c getdtablesize.c create_module.c ptrace.c \
@@ -44,13 +39,21 @@ COBJS=$(patsubst %.c,%.o, $(CSRC))
MSRC=syscalls.c
MOBJ=$(shell ./list_syscalls.sh)
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+CTOR_TARGETS=$(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o
+SAFECFLAGS=$(WARNINGS) $(CPU_CFLAGS-y) $(OPTIMIZATION) -fno-builtin
+ifeq ($(strip $(DOPIC)),y)
+SAFECFLAGS+=-fPIC
+endif
+endif
+
OBJ=$(COBJS) $(MOBJ)
all: $(STR_SYSCALLS) $(OBJ) $(LIBC)
$(LIBC): ar-target
-ar-target: $(OBJ) $(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o
+ar-target: $(OBJ) $(CTOR_TARGETS)
$(AR) $(ARFLAGS) $(LIBC) $(OBJ)
(cd $(TOPDIR)lib/; ln -fs crt0.o crt1.o)
diff --git a/libc/sysdeps/linux/i386/crt0.S b/libc/sysdeps/linux/i386/crt0.S
index 97f1fde63..be66b9a2d 100644
--- a/libc/sysdeps/linux/i386/crt0.S
+++ b/libc/sysdeps/linux/i386/crt0.S
@@ -61,6 +61,7 @@ _start:
pushl %ebp /* callers %ebp (frame pointer) */
movl %esp,%ebp /* mark callers stack frame as invalid */
+#ifdef __UCLIBC_CTOR_DTOR__
/* Push .init and .fini arguments to __uClibc_start_main() on the stack */
pushl $_fini
pushl $_init
@@ -72,6 +73,14 @@ _start:
/* Ok, now run uClibc's main() -- shouldn't return */
call __uClibc_start_main
+#else
+ /* Push envp, argc, and argc arguments to __uClibc_start_main() on the stack */
+ pushl %eax /* Environment pointer */
+ pushl %ebx /* Argument pointer */
+ pushl %ecx /* And the argument count */
+
+ call __uClibc_main
+#endif
/* Crash if somehow `exit' returns anyways. */
hlt
diff --git a/libc/sysdeps/linux/mips/crt0.S b/libc/sysdeps/linux/mips/crt0.S
index fd1f4b9d4..052229819 100644
--- a/libc/sysdeps/linux/mips/crt0.S
+++ b/libc/sysdeps/linux/mips/crt0.S
@@ -30,6 +30,7 @@ __start:
addu a2, a0, 1 /* argv[0] program name (ordinal->cardinal) */
sll a2, a2, 2 /* multiple by 4 */
add a2, a2, a1 /* a2 now points to start of envp */
+#ifdef __UCLIBC_CTOR_DTOR__
la a3, _init /* a3 is address of _init */
addiu sp, sp, -24 /* 16 + 4 rounded up to multiple of 8 */
/* multiple of 8 for longlong/double support */
@@ -38,6 +39,9 @@ __start:
/* Ok, now run uClibc's main() -- shouldn't return */
jal __uClibc_start_main
+#else
+ jal __uClibc_main
+#endif
addiu sp, sp, 24 /* undo stack argument */
diff --git a/libc/sysdeps/linux/sh/crt0.S b/libc/sysdeps/linux/sh/crt0.S
index e74ae86c4..a27775ed0 100644
--- a/libc/sysdeps/linux/sh/crt0.S
+++ b/libc/sysdeps/linux/sh/crt0.S
@@ -48,6 +48,34 @@ _start:
mov.l @r15+,r4
mov r15, r5
+#if ! defined __UCLIBC_CTOR_DTOR__
+ /*
+ * Setup the value for the environment pointer:
+ * r6 = (argc + 1) * 4
+ * r6 += argv (in delay slot)
+ */
+ mov r4,r6
+ add #1,r6
+ shll2 r6
+ add r5, r6
+
+ /* jump to __uClibc_main (argc, argv, envp) */
+ mov.l L_main, r0
+ jsr @r0
+ nop /* delay slot */
+
+ /* We should not get here. */
+ mov.l L_abort, r0
+ jmp @r0
+ nop
+
+_start_end:
+ .align 2
+
+L_main:
+ .long __uClibc_main /* in libuClibc.*.so */
+
+#else /* __UCLIBC_CTOR_DTOR__ */
/* Push the finip argument to __uClibc_start_main() onto the stack */
mov.l L_fini,r6
mov.l r6,@-r15
@@ -72,10 +100,12 @@ _start:
mov.l L_abort, r0
jmp @r0
nop
-
_start_end:
.align 2
+L_main:
+ .long __uClibc_start_main /* in libuClibc.*.so */
+
.weak _init
.type _init,@function
_init:
@@ -87,13 +117,13 @@ _init:
.weak _fini
.set _fini,_init
-L_main:
- .long __uClibc_start_main /* in libuClibc.*.so */
-
L_init:
.long _init
L_fini:
.long _fini
+
+#endif
+
L_abort:
.long abort
diff --git a/libpthread/Makefile b/libpthread/Makefile
index c98ef8bda..87e20749f 100644
--- a/libpthread/Makefile
+++ b/libpthread/Makefile
@@ -36,6 +36,7 @@ ifeq ($(strip $(DODEBUG)),y)
endif
endif
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
ifeq ($(strip $(DOPIC)),y)
START_FILES = $(TOPDIR)lib/crti.o $(LIBGCC_DIR)crtbeginS.o
END_FILES = $(LIBGCC_DIR)crtendS.o $(TOPDIR)lib/crtn.o
@@ -43,6 +44,7 @@ else
START_FILES = $(TOPDIR)lib/crti.o $(LIBGCC_DIR)crtbegin.o
END_FILES = $(LIBGCC_DIR)crtend.o $(TOPDIR)lib/crtn.o
endif
+endif
ALL_SUBDIRS = linuxthreads linuxthreads_db