[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Austin Lamb added the comment: Thanks Steve! -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Steve Dower added the comment: The ping was enough. Thanks! -- assignee: -> steve.dower resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker __

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Steve Dower added the comment: New changeset b4af629f4d4868ef74ee298d66259fae78c7fd89 by Austin Lamb in branch 'master': bpo-42825: Enable /OPT:REF (GH-24098) https://github.com/python/cpython/commit/b4af629f4d4868ef74ee298d66259fae78c7fd89 -- __

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Austin Lamb added the comment: What are the next steps for this - anything else I can provide, or is someone able to take a look at the Pull Request? Thanks! -- ___ Python tracker _

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Change by John Rey Osano : -- components: +C API, Extension Modules, IO type: performance -> enhancement ___ Python tracker ___ ___

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Austin Lamb added the comment: You're right to think that folding is a problem Steve, but thankfully my PR does not enable COMDAT folding for that very reason :). /OPT:ICF enables identical COMDAT folding, but surprisingly-to-me /OPT:REF seems to still enable a small amount of folding (I co

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Steve Dower added the comment: On Windows it should only affect non-exported functions. Comparing "dumpbin /exports" output will tell you whether anything has changed there. The bigger concern is if it merges identical functions that are compared by function pointer. I know we've had issues

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Austin Lamb added the comment: Ping - can anyone suggest either how ctypes does its exporting, or suggest tests I could run to confirm if this change affects python code? The entire test suite in the repo passes. -- ___ Python tracker

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Austin Lamb added the comment: I don't know much about how ctypes exposes stuff - are these exposed as DLL exports? Or if not, how do they get exposed? The linker will remove things it can't find a callsite for, but it leaves in exported functions as of course those are by definition extern

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Terry J. Reedy added the comment: The PR says that this deletes "uncalled code". I imagine that this is safe for a .exe. But for a .dll? As i understand it, one can, from python code, access any function via ctypes, so it seems to me that there is no way for the linker to know which calla

[issue42825] Build libraries with "/OPT:REF" linker optimization on Windows

Change by Ammar Askar : -- nosy: +eryksun title: Optimization opportunity on Windows -> Build libraries with "/OPT:REF" linker optimization on Windows ___ Python tracker ___ _