Author: uweigand Date: Thu Apr 14 09:36:29 2016 New Revision: 266316 URL: http://llvm.org/viewvc/llvm-project?rev=266316&view=rev Log: Find .plt section in object files generated by recent ld
Code in ObjectFileELF::ParseTrampolineSymbols assumes that the sh_info field of the .rel(a).plt section identifies the .plt section. However, with recent GNU ld this is no longer true. As a result of this: https://sourceware.org/bugzilla/show_bug.cgi?id=18169 in object files generated with current linkers the sh_info field of .rel(a).plt now points to the .got.plt section (or .got on some targets). This causes LLDB to fail to identify any PLT stubs, causing a number of test case failures. This patch changes LLDB to simply always look for the .plt section by name. This should be safe across all linkers and targets. Differential Revision: http://reviews.llvm.org/D18973 Modified: lldb/trunk/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp Modified: lldb/trunk/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp?rev=266316&r1=266315&r2=266316&view=diff ============================================================================== --- lldb/trunk/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp (original) +++ lldb/trunk/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp Thu Apr 14 09:36:29 2016 @@ -2611,17 +2611,17 @@ ObjectFileELF::ParseTrampolineSymbols(Sy { assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL); - // The link field points to the associated symbol table. The info field - // points to the section holding the plt. + // The link field points to the associated symbol table. user_id_t symtab_id = rel_hdr->sh_link; - user_id_t plt_id = rel_hdr->sh_info; // If the link field doesn't point to the appropriate symbol name table then // try to find it by name as some compiler don't fill in the link fields. if (!symtab_id) symtab_id = GetSectionIndexByName(".dynsym"); - if (!plt_id) - plt_id = GetSectionIndexByName(".plt"); + + // Get PLT section. We cannot use rel_hdr->sh_info, since current linkers + // point that to the .got.plt or .got section instead of .plt. + user_id_t plt_id = GetSectionIndexByName(".plt"); if (!symtab_id || !plt_id) return 0; _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
