[PATCH] D97430: [SanitizerCoverage] Drop !associated on metadata sections

[Fangrui Song via Phabricator via llvm-commits]

MaskRay added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/Instrumentation.cpp:76
 
-Comdat *llvm::GetOrCreateFunctionComdat(Function &F, Triple &T,
-                                        const std::string &ModuleId) {
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ychen wrote:
> Internally, I saw this failure https://github.com/llvm/llvm-project/blob/a6a57f03be40cf2c546805155624a206649092ec/llvm/lib/Linker/LinkModules.cpp#L181 that may be caused by this for a test built with `-fprofile-generate -flto` for ELF. According to the title and description of the patch, that seems an unintended behavior change. Just check in to see if it is obvious how to fix this. Will provide the reproducer once it is available.
Is it called by the legacy LTO implementation `LTOCodeGenerator::addModule`? I guess new LTO does not exercise the code path.

I guess the fix is to ignore deduplication feature in `ModuleLinker::run` `ComdatsChosen`. `comdat nodeduplicates` was added to ELF this year.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D97430/new/

https://reviews.llvm.org/D97430