[PATCH] D107747: [ELF] Don't emit SHF_GNU_RETAIN on Solaris

Tue Aug 10 11:59:26 PDT 2021

MaskRay accepted this revision.
MaskRay added a comment.
This revision is now accepted and ready to land.

In D107747#2936740 <https://reviews.llvm.org/D107747#2936740>, @ro wrote:

> In D107747#2934856 <https://reviews.llvm.org/D107747#2934856>, @MaskRay wrote:
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>> Instrumentation based PGO has names variables referenced by `llvm.used`. Without a `SHF_GNU_RETAIN` counterpart indirect call profiling cannot work.
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> But isn't this the same with pre-binutils 2.36 GNU `ld` and still there are no precautions about this case?

The issue can be mitigated by a hack in GNU ld and gold: 
https://maskray.me/blog/2021-01-31-metadata-sections-comdat-and-shf-link-order#reflection
(In the Solaris Linkers and Libraries guide, such `__start_` and `__stop_` symbols are called encapsulation symbols.)

Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D107747/new/

https://reviews.llvm.org/D107747