Author: Igor Kudrin Date: 2021-12-13T15:47:32-08:00 New Revision: 52bfd2c1ccd86ff813ee6df5a6700690acdd912f
URL: https://github.com/llvm/llvm-project/commit/52bfd2c1ccd86ff813ee6df5a6700690acdd912f DIFF: https://github.com/llvm/llvm-project/commit/52bfd2c1ccd86ff813ee6df5a6700690acdd912f.diff LOG: [ELF] Do not report undefined weak references in shared libraries This fixes an issue introduced in D101996. A weak reference in a shared library could be incorrectly reported if there is another library that has a strong reference to the same symbol. Differential Revision: https://reviews.llvm.org/D115041 (cherry picked from commit ce25eb12dd5abae6c769168a70a8f377b608228c) Added: lld/test/ELF/allow-shlib-undefined-weak.s Modified: lld/ELF/InputFiles.cpp Removed: ################################################################################ diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp index d5b9efbe18fc5..ab65571887d1f 100644 --- a/lld/ELF/InputFiles.cpp +++ b/lld/ELF/InputFiles.cpp @@ -1567,7 +1567,7 @@ template <class ELFT> void SharedFile::parse() { Symbol *s = symtab->addSymbol( Undefined{this, name, sym.getBinding(), sym.st_other, sym.getType()}); s->exportDynamic = true; - if (s->isUndefined() && !s->isWeak() && + if (s->isUndefined() && sym.getBinding() != STB_WEAK && config->unresolvedSymbolsInShlib != UnresolvedPolicy::Ignore) requiredSymbols.push_back(s); continue; diff --git a/lld/test/ELF/allow-shlib-undefined-weak.s b/lld/test/ELF/allow-shlib-undefined-weak.s new file mode 100644 index 0000000000000..1037cbed0d859 --- /dev/null +++ b/lld/test/ELF/allow-shlib-undefined-weak.s @@ -0,0 +1,48 @@ +# REQUIRES: x86 + +# RUN: rm -rf %t.dir +# RUN: split-file %s %t.dir +# RUN: cd %t.dir + +## Verify that in the following case: +## +## <exec> +## +- ref.so (weak reference to foo) +## +- wrap.so (non-weak reference to foo) +## +- def.so (defines foo) +## +## we don't report that foo is undefined in ref.so when linking <exec>. + +# RUN: llvm-mc -filetype=obj -triple=x86_64 ref.s -o ref.o +# RUN: llvm-mc -filetype=obj -triple=x86_64 wrap.s -o wrap.o +# RUN: llvm-mc -filetype=obj -triple=x86_64 def.s -o def.o +# RUN: ld.lld -shared ref.o -o ref.so +# RUN: ld.lld -shared def.o -soname def.so -o def.so +# RUN: ld.lld -shared wrap.o def.so -o wrap.so + +# RUN: llvm-mc -filetype=obj -triple=x86_64 start.s -o start.o +# RUN: ld.lld --no-allow-shlib-undefined start.o wrap.so ref.so -o /dev/null 2>&1 | count 0 + +#--- start.s +.globl _start +_start: + callq wrap_get_foo@PLT + +#--- ref.s +.weak foo +.globl ref_get_foo +ref_get_foo: + movq foo@GOTPCREL(%rip), %rax + retq + +#--- wrap.s +.globl wrap_get_foo +wrap_get_foo: + movq foo@GOTPCREL(%rip), %rax + retq + +#--- def.s +.data +.globl foo +foo: + .long 0 _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
