Sources Bugzilla – Bug 13177
garbage collector retains zombie references to external libraries
Last modified: 2012-02-22 03:35:16 UTC
If shared library is compiled and linked with garbage collection enabled, zombie references to external libraries are retained that result future link failure. (ld 2.21, gcc 4.5.2, Ubuntu 11.04) Steps to repro: * Create file shared.c --8<-- #include <dlfcn.h> void opt_out(const char *name) { dlopen(name, RTLD_LAZY); } __attribute__ ((visibility ("default"))) int add_two(int number) { return number+2; } -->8-- * Create shared library by running gcc -fpic -shared -ffunction-sections -fdata-sections -Wl,--gc-sections -fvisibility=hidden -o libtest.so shared.c -static-libgcc Result: SUCCESS, no errors. * Verify created library references by running ldd -r libtest.so Resukt: SUCCESS. No unreferenced symbols and expected list of library bindings. * Create file main.c: --8<-- int add_two(int); int main() { return add_two(-2); } -->8-- * Create a program by running: gcc -o main main.c -L. -ltest Expected result: Program compailes and links correctly. Acttual result: FAIL. ld returns: ./libtest.so: undefined reference to 'dlopen' collect2: ld returned 1 exit status
A patch is posted at http://sourceware.org/ml/binutils/2011-09/msg00076.html
CVSROOT: /cvs/src Module name: src Changes by: hjl@sourceware.org 2011-09-16 01:17:16 Modified files: ld/testsuite : ChangeLog bfd : ChangeLog elflink.c Added files: ld/testsuite/ld-elf: pr13177.d pr13177.s Log message: Also hide symbols without PLT nor GOT references. bfd/ 2011-09-15 H.J. Lu <hongjiu.lu@intel.com> PR ld/13177 * elflink.c (elf_gc_sweep_symbol): Also hide symbols without PLT nor GOT references. ld/testsuite/ 2011-09-15 H.J. Lu <hongjiu.lu@intel.com> PR ld/13177 * ld-elf/pr13177.d: New. * ld-elf/pr13177.s: Likewise. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ChangeLog.diff?cvsroot=src&r1=1.1458&r2=1.1459 pr13177.d.diff?cvsroot=src&r1=NONE&r2=1.1">http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-elf/pr13177.d.diff?cvsroot=src&r1=NONE&r2=1.1 pr13177.s.diff?cvsroot=src&r1=NONE&r2=1.1">http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-elf/pr13177.s.diff?cvsroot=src&r1=NONE&r2=1.1 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/ChangeLog.diff?cvsroot=src&r1=1.5470&r2=1.5471 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elflink.c.diff?cvsroot=src&r1=1.419&r2=1.420
Fixed.
CVSROOT: /cvs/src Module name: src Branch: binutils-2_22-branch Changes by: hjl@sourceware.org 2011-10-18 19:06:50 Modified files: ld/testsuite : ChangeLog bfd : ChangeLog elflink.c Removed files: ld/testsuite/ld-elf: pr13177.d pr13177.s Log message: Revert the fix for PR ld/13177. bfd/ 2011-10-18 H.J. Lu <hongjiu.lu@intel.com> PR ld/13177 * elflink.c (elf_gc_sweep_symbol): Don't hide symbols without PLT nor GOT references. ld/testsuite/ 2011-10-18 H.J. Lu <hongjiu.lu@intel.com> PR ld/13177 * ld-elf/pr13177.d: Removed. * ld-elf/pr13177.s: Likewise. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ChangeLog.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.1460.2.2&r2=1.1460.2.3 pr13177.d.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.2&r2=NONE">http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-elf/pr13177.d.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.2&r2=NONE pr13177.s.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.2&r2=NONE">http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-elf/pr13177.s.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.2&r2=NONE http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/ChangeLog.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.5473.2.5&r2=1.5473.2.6 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elflink.c.diff?cvsroot=src&only_with_tag=binutils-2_22-branch&r1=1.420.2.2&r2=1.420.2.3
Patch is reverted on 2.22 branch,
CVSROOT: /cvs/src Module name: src Changes by: amodra@sourceware.org 2011-10-19 07:17:21 Modified files: bfd : ChangeLog elf32-arm.c elf32-bfin.c elf32-cris.c elf32-frv.c elf32-i386.c elf32-m32r.c elf32-m68k.c elf32-ppc.c elf32-s390.c elf32-sh.c elf32-spu.c elf32-tilepro.c elf32-xtensa.c elf64-alpha.c elf64-ppc.c elf64-s390.c elf64-sh64.c elf64-x86-64.c elflink.c elf-m10300.c elfxx-sparc.c elfxx-tilegx.c ld/testsuite : ChangeLog ld/testsuite/ld-elf: elf.exp ld/testsuite/ld-gc: gc.exp ld/testsuite/lib: ld-lib.exp Added files: ld/testsuite/ld-gc: libpersonality.s personality.d personality.s Log message: PR ld/13177 bfd/ * elflink.c (_bfd_elf_gc_mark_rsec): Set symbol "mark". (elf_gc_sweep_symbol): Don't test plt/got refcounts, instead test "mark". Hide undefweak too. Clear def_regular and ref_regular. * elf-m10300.c (mn10300_elf_relocate_section): Ignore unresolved reloc errors from garbage-collected code. * elf32-arm.c (elf32_arm_relocate_section): Likewise. * elf32-bfin.c (bfin_relocate_section): Likewise. (bfinfdpic_relocate_section): Likewise. * elf32-cris.c (cris_elf_relocate_section): Likewise. * elf32-frv.c (elf32_frv_relocate_section): Likewise. * elf32-i386.c (elf_i386_relocate_section): Likewise. * elf32-m32r.c (m32r_elf_relocate_section): Likewise. * elf32-m68k.c (elf_m68k_relocate_section): Likewise. * elf32-ppc.c (ppc_elf_relocate_section): Likewise. * elf32-s390.c (elf_s390_relocate_section): Likewise. * elf32-sh.c (sh_elf_relocate_section): Likewise. * elf32-spu.c (spu_elf_relocate_section): Likewise. * elf32-tilepro.c (tilepro_elf_relocate_section): Likewise. * elf32-xtensa.c (elf_xtensa_relocate_section): Likewise. * elf64-alpha.c (elf64_alpha_relocate_section): Likewise. * elf64-ppc.c (ppc64_elf_relocate_section): Likewise. * elf64-s390.c (elf_s390_relocate_section): Likewise. * elf64-sh64.c (sh_elf64_relocate_section): Likewise. * elf64-x86-64.c (elf_x86_64_relocate_section): Likewise. * elfxx-sparc.c (_bfd_sparc_elf_relocate_section): Likewise. * elfxx-tilegx.c (tilegx_elf_relocate_section): Likewise. ld/testsuite/ * ld-elf/elf.exp: Move test for shared lib support.. * lib/ld-lib.exp (check_shared_lib_support): ..to here. Add m68hc1*, and s/ms1/mt/. (check_gc_sections_available): Match hppa*64 not hppa64. Comment. * ld-gc/libpersonality.s: New. * ld-gc/personality.s, * ld-gc/personality.d: New. * ld-gc/gc.exp: Run personality test. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/ChangeLog.diff?cvsroot=src&r1=1.5494&r2=1.5495 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-arm.c.diff?cvsroot=src&r1=1.277&r2=1.278 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-bfin.c.diff?cvsroot=src&r1=1.54&r2=1.55 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-cris.c.diff?cvsroot=src&r1=1.116&r2=1.117 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-frv.c.diff?cvsroot=src&r1=1.73&r2=1.74 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-i386.c.diff?cvsroot=src&r1=1.260&r2=1.261 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-m32r.c.diff?cvsroot=src&r1=1.102&r2=1.103 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-m68k.c.diff?cvsroot=src&r1=1.126&r2=1.127 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-ppc.c.diff?cvsroot=src&r1=1.302&r2=1.303 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-s390.c.diff?cvsroot=src&r1=1.108&r2=1.109 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-sh.c.diff?cvsroot=src&r1=1.172&r2=1.173 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-spu.c.diff?cvsroot=src&r1=1.101&r2=1.102 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-tilepro.c.diff?cvsroot=src&r1=1.3&r2=1.4 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf32-xtensa.c.diff?cvsroot=src&r1=1.130&r2=1.131 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf64-alpha.c.diff?cvsroot=src&r1=1.181&r2=1.182 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf64-ppc.c.diff?cvsroot=src&r1=1.366&r2=1.367 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf64-s390.c.diff?cvsroot=src&r1=1.108&r2=1.109 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf64-sh64.c.diff?cvsroot=src&r1=1.87&r2=1.88 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf64-x86-64.c.diff?cvsroot=src&r1=1.239&r2=1.240 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elflink.c.diff?cvsroot=src&r1=1.427&r2=1.428 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elf-m10300.c.diff?cvsroot=src&r1=1.108&r2=1.109 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elfxx-sparc.c.diff?cvsroot=src&r1=1.61&r2=1.62 http://sourceware.org/cgi-bin/cvsweb.cgi/src/bfd/elfxx-tilegx.c.diff?cvsroot=src&r1=1.3&r2=1.4 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ChangeLog.diff?cvsroot=src&r1=1.1470&r2=1.1471 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-elf/elf.exp.diff?cvsroot=src&r1=1.30&r2=1.31 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-gc/libpersonality.s.diff?cvsroot=src&r1=NONE&r2=1.1 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-gc/personality.d.diff?cvsroot=src&r1=NONE&r2=1.1 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-gc/personality.s.diff?cvsroot=src&r1=NONE&r2=1.1 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/ld-gc/gc.exp.diff?cvsroot=src&r1=1.11&r2=1.12 http://sourceware.org/cgi-bin/cvsweb.cgi/src/ld/testsuite/lib/ld-lib.exp.diff?cvsroot=src&r1=1.85&r2=1.86
Fixed mainline