Now I played a bit with it based on your example from bug report and adding "extern const PIMAGE_TLS_CALLBACK __xl_f;" is NOT fixing the problem when the /O2 /GL flags are used.
Here is the link to godbolt where anybody can play with it and verify what is working what not: https://godbolt.org/z/z4sreEcY4 So based on above testing, I think that the additional declaration with extern keyword is unnecessary and does not fix the main issue when /GL together with /O2 is enabled. I do not know how to fix it. On Tuesday 23 September 2025 14:38:37 Pali Rohár wrote: > That it really interesting. At least it proves that I was wrong about > /include: assumption. > > So if I understand correctly, if you add following line to your example > then it start working, right? "extern const PIMAGE_TLS_CALLBACK __xl_f;" > > In this case the extern is there needed for msvc and I would suggest to > add a comment into mingw-w64 why additional extern declaration (which > seems unnecessary from C point of view) is required. > > On Tuesday 23 September 2025 14:10:31 Antonin Décimo wrote: > > I experimented with MSVC and LTO two years ago, and had problems > > applying them to winpthreads. I may not have been very rigorous, and > > to get certainty the whole process would need to be re-tested. I did > > report a bug, but it was deemed invalid. > > https://developercommunity.visualstudio.com/t/Whole-program-optimization-and-optimized/10531811 _______________________________________________ Mingw-w64-public mailing list Mingw-w64-public@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
