[clang] [llvm] [CodeGen][COFF] Always emit CodeView compiler info on Windows targets (PR #142970)

[Martin Storsjö via llvm-commits]

mstorsjo wrote:

> I wasn't sure whether to enable this for UEFI targets as well, so I didn't. I enabled it for MinGW targets too, since I saw no reason to treat them differently.

Hmm, so a "regular" mingw object file would end up having both DWARF (if building with `-g`) and codeview (for the compiler info)? Does this cause confusion when linking (probably not, as it would either retain the DWARF or the codeview parts, depending on linker arguments I guess)? If GNU ld bails out on this we probably shouldn't, but at least recent versions should cope with it I think. It may be good to verify that it doesn't end up triggering GNU ld to produce only PDB output instead of the expected embedded DWARF, or something like that.

https://github.com/llvm/llvm-project/pull/142970