[compiler-rt] [Profile] Dump binary id to raw profiles on Windows. (PR #75618)

[Zequan Wu via llvm-commits]

ZequanWu wrote:

> It looks like this breaks the build when using mingw:
> 
> > C:/a/rust/rust/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: C:\a\rust\rust\build\x86_64-pc-windows-gnu\stage2\lib\rustlib\x86_64-pc-windows-gnu\lib\libprofiler_builtins-06ad067b40ce3a0d.rlib(InstrProfilingPlatformWindows.o):InstrProfilingPlatformWindows.c:(.rdata$.refptr.__buildid[.refptr.__buildid]+0x0): undefined reference to `__buildid'
> 
> I don't really get how this code is supposed to work, I don't think extern selectany supports symbols that are not defined?

Yeah, I think I should drop `extern`: #80700

https://github.com/llvm/llvm-project/pull/75618