erichkeane added a comment. In D147655#4251984 <https://reviews.llvm.org/D147655#4251984>, @rsmith wrote:
> In D147655#4251042 <https://reviews.llvm.org/D147655#4251042>, @aaron.ballman > wrote: > >> In D147655#4250922 <https://reviews.llvm.org/D147655#4250922>, @royjacobson >> wrote: >> >>> In D147655#4250056 <https://reviews.llvm.org/D147655#4250056>, @rsmith >>> wrote: >>> >>>> There has not been any stable ABI from any compiler targeting the Itanium >>>> C++ ABI for constrained templates prior to this change. I don't think we >>>> need to worry too much about people using unfinished compiler features >>>> being broken when those features are finished. >>> >>> The ABI has been stable for quite some time and people have been using >>> concepts with it for almost 3 years now. I'm not sure we can still break >>> ABI this easily. But then, I also have no data to say we can't. >> >> We've never claimed full support for concepts, so those folks would be >> relying on an unstable ABI. However, if it turns out this causes significant >> pain in practice, perhaps we could use ABI tags to give folks the older ABI? >> I'd prefer to avoid that in this case given that the feature isn't yet fully >> supported (I don't like the idea of setting a precedent for relying on the >> ABI of incomplete features in general), but concepts is a sufficiently >> important use case that I could imagine doing it as a one-off if needed. > > This patch already extends `-fclang-abi-compat` to retain the old manglings > so that users can stay on an old (broken) ABI if they need to. I don't think > we need to do more than that for the concepts mangling changes. > >>>> The ABI proposals haven't been accepted yet; I'm not intending to land >>>> this change until the proposals have reached consensus in the Itanium C++ >>>> ABI group. > > The corresponding (confirmed) GCC bug report that they don't implement these > mangling rules yet is: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100825 > > This patch supersedes https://reviews.llvm.org/D126818 (apologies for the > duplicated work, @erichkeane -- I didn't find that before I started working > on this). No problem! This is a much more complete solution, and mine was held up on waiting for the Itanium ABI group to come to a consensus anyway (and fell by the wayside). Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D147655/new/ https://reviews.llvm.org/D147655 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
