MaskRay added a comment. From @dblaikie's email reply:
> ^ this I would consider to be a bug. -g should be needed to generate debug > info into the IR, and -gsplit-dwarf should be needed to choose how debug info > already in the IR should be placed into object files or dwo files. > > Usually (non-LTO) these two steps are in the same compile, so -g and > -gsplit-dwarf go together. But for LTO cases, I think it's suitable for -g to > be needed for IR generation, and -gsplit-dwarf to be needed for object code > generation, without needing -g as well in that latter step (the -g was > already specified at IR generation time, and that shoul be enough). > > We can see that behavior I'm describing as desirable in implicit ThinLTO I > showed earlier in the thread. > > I suggest this should be the desired behavior, because -g generally has no > effect on IR->object code generation, so it seems strange/unnecessary to me > to gate -gsplit-dwarf behind -g in that case. The -g was already specified > and used during IR generation (& the -gN level, -gmlt behavior-etc has all > been handled in IR generation (or embedded in the IR for use later) - so to > me, specifying -g again during object code generation would be/is strange, > because any special values would be ignored (-g1/g2/g3/etc would not be > respected - the N value would only be respected when passed to the IR > generation step)) Got it. `-fthinlto-index=` (thinlto backend compile) operates on bitcode files and does not IR generation. It isn't suitable for `-g` to be needed to use. -gsplit-dwarf is both an IR generation option and a code generation option. It is needed for thinlto backend compiles. In Bazel, I think a typical configuration's `LTO Backend Compile` includes almost every option in the initial compile, so I did not notice the issue. I am working on a patch. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D80391/new/ https://reviews.llvm.org/D80391 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
