Bug 2156679

Summary: Build Clang with PGO
Product: [Fedora] Fedora Reporter: Alexander Zaitsev <zamazan4ik>
Component: clangAssignee: Tom Stellard <tstellar>
Status: CLOSED RAWHIDE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: medium    
Version: 42CC: airlied, jchecahi, kkleine, npopov, sbergman, sergesanspaille, siddharth.kde, tstellar, tuliom
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Last Closed: 2025-06-13 14:04:59 UTC Type: Bug
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Description Alexander Zaitsev 2022-12-28 06:22:01 UTC 
Description of problem:

Clang supports (https://llvm.org/docs/HowToBuildWithPGO.html) bootstrapping with PGO. It increases Clang performance. The same thing is already enabled for GCC in Fedora (profiledbootstrap option). I think the same thing could be done for Clang since in the current build script I don't see that Clang is built with PGO.


Expected results:
Provided Clang binaries with Fedora are built with PGO.

Additional option:
Also you could try to build binary with LLVM BOLT (https://github.com/facebookincubator/BOLT/blob/main/bolt/docs/OptimizingClang.md) but I guess it's another question and it's much more complicated topic.
Comment 1 Ben Cotton 2023-02-07 15:04:14 UTC 
This bug appears to have been reported against 'rawhide' during the Fedora Linux 38 development cycle.
Changing version to 38.
Comment 2 Aoife Moloney 2025-02-26 12:53:02 UTC 
This bug appears to have been reported against 'rawhide' during the Fedora Linux 42 development cycle.
Changing version to 42.
Comment 3 Tulio Magno Quites Machado Filho 2025-06-13 14:04:59 UTC 
This has been implemented in Rawhide and should be available in Fedora 43 with LLVM 21.