SjoerdMeijer added inline comments.
================ Comment at: clang/lib/Frontend/CompilerInvocation.cpp:3080 } Opts.setFPExceptionMode(FPEB); ---------------- jansvoboda11 wrote: > SjoerdMeijer wrote: > > jansvoboda11 wrote: > > > The parsing of `OPT_ftrapping_math` and `OPT_fno_trapping_math` is > > > immediately overwritten here. > > Yeah, I did some work in this area some years ago, but that's a few years > > ago, and then in addition to that, we are talking about option handling in > > Clang which I always find very confusing... Just saying I can't remember > > too many details at this point. > > > > But starting with a first observation, you're saying that things are > > overwritten here, but they are different options. I.e., the deleted part > > honours `OPT_ftrapping_math`, and here exception modes are set based on > > `OPT_ffp_exception_behavior`. So, looks like there is some interaction > > here... Do we know how this should work? > I see. The thing is, before this patch, we call `Opts.setFPExceptionMode` > whenever we see either `OPT_ftrapping_math` or `OPT_fno_trapping_math`. > > But then, we **unconditionally** call `Opts.setFPExceptionMode(FPEB)` again > here. That **always** overwrites what we previously did for > `OPT_f[no_]trapping_math`, making that a dead code. > > `Opts.setFPExceptionMode()` doesn't do anything fancy, just assigns the > argument to the `Opts.FPExceptionModel` member. Ah yes, I actually missed that we always set `Opts.setFPExceptionMode(FPEB)` here! So that's clear now. But looks like my previous question is still relevant how these options should work together? I now see that `-ffp-exception-behavior` is a intel/microsoft special introduced in D62731. And while currently we ignore `-fftrapping-math` here, but that just seems like a bug, it looks like we actually need to handle it here too? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D93395/new/ https://reviews.llvm.org/D93395 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
