gh-101525: [BOLT] Add GCC's LTO-generated function clones, with computed gotos, to BOLT skip list #139840
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stratakis requested review from AA-Turner, corona10, emmatyping and erlend-aasland as code owners 
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| cc @corona10 |
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| I will try to review this PR until end of this week. |
…ed gotos, to BOLT skip list When building with --with-lto, --enable-bolt and --enable-shared, GCC creates optimized function clones with the suffix .lto_priv.0. The sre_ucs*_match functions use computed gotos, which BOLT cannot optimize, so their .lto_priv.0 clones must be skipped as well. Static builds and Clang's LTO implementation are not affected.
corona10 approved these changes Oct 19, 2025
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LGTM!
But since LLVM 20 has been released and llvm/llvm-project#120267
is merged, it’s probably a good time to test without using -skip-funcs :)
cc @zanieb
Contributor Author
I did some testing there with GCC. #140250 works, unless the linker uses -pack-relative-relocs, then those functions fail again. |
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| Would it make sense to backport this to previous versions, as it's a bugfix? |
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Yes, I think so. Do you agree to backport @corona10? |
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When building with --with-lto, --enable-bolt and --enable-shared, GCC creates optimized function clones with the suffix .lto_priv.0.
The sre_ucs*_match functions use computed gotos, which BOLT cannot optimize, so their .lto_priv.0 clones must be skipped as well.
Static builds and Clang's LTO implementation are not affected.