ychen added a comment. In D128745#3832432 <https://reviews.llvm.org/D128745#3832432>, @rjmccall wrote:
> Pinging this thread because it has more reviewers who probably have opinions > about this. > > https://reviews.llvm.org/D134507 is a patch that adds `-fclang-abi-compat` > support around the breaking change here, which basically means that targets > using old `-fclang-abi-compat` settings never get this change. I've argued > on that patch that that isn't the right way of resolving this issue. > Basically, the DR here is changing the language behavior in a way that you > can imagine having ABI impact, but it's not primarily an ABI change, it's a > language semantics change. The ABI impact is purely that we potentially > select a different overload in some cases, which can have downstream ODR > impact. I think the appropriate way to handle language semantics changes > like this which potentially have compatibility impact is to condition them on > language version. Changing the target language standard is already broadly > understood to have source/semantic compatibility impact, which is why we > allow different target language standards to be specified in the first place. > This also makes it straightforward to document this potential break as a > consequence of moving to `-std=c++23`, and it removes a potential rather > bizarre portability issue where platforms that embrace stable ABIs are > permanently stuck with a language dialect. This is very reasonable to me except that I hope, for this particular patch, to key on `-std=c++20` instead of `-std=c++23` since this is needed for P2113 <https://reviews.llvm.org/P2113>, a C++20 change. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D128745/new/ https://reviews.llvm.org/D128745 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
