dblaikie added a comment. In D135326#3853324 <https://reviews.llvm.org/D135326#3853324>, @rjmccall wrote:
> In D135326#3851678 <https://reviews.llvm.org/D135326#3851678>, @dblaikie > wrote: > >> In D135326#3851672 <https://reviews.llvm.org/D135326#3851672>, @dblaikie >> wrote: >> >>> (abandoned this, but still kind of curious) >>> >>> @rjmccall - any background/history of having the CXXABI distinct from the >>> OS? I guess the point might've been that the C ABI is part of/the >>> definition of the OS, but maybe the CXX ABI is more "floating"/flexible on >>> top of that? Though it means these CXX ABIs don't get the benefit of being >>> grouped with the rest of the targetOS - instead they're a bunch of >>> switches, which seems a bit unfortunate, but I guess there's not lots of >>> properties here, so maybe that's OK. >> >> I guess the other question: Is this flexibility valuable/worthwhile, or >> could we fold the CXXABI back into the TargetOS? > > I don't think we really want to support targeting an OS while independently > changing the target C++ ABI, no. But I think "OS implies C++ ABI implies ABI > properties" is generally the way people define platforms, and I wouldn't want > to create a situation where targets have to manually implement all of the > right C++ ABI properties just to get default behavior for a specific C++ ABI > or else end up weirdly divergent. If you have a different way to achieve > that goal besides composition, that's worth considering. Thanks for the reply! Ah, I think I see what you mean. So we could remove the `-fc++-abi` flag? (well, it's a driver flag... - deprecate it? make it a no-op or an error if you ask for an abi that isn't the one the OS already implies?) & then maybe ABI could be a mixin the same way TargetOS works? (TargetOS could mixin the C++ ABI, then TargetInfo mixes in TargetOS) Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D135326/new/ https://reviews.llvm.org/D135326 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
