erichkeane added inline comments.
================ Comment at: clang/lib/Parse/ParseTemplate.cpp:876 +/// In C++20: +/// template-head: [C++ temp.pre] +/// template '<' template-parameter-list '>' requires-clause[opt] ---------------- aaron.ballman wrote: > Rather than duplicate the grammar for each standard revision, I think we > usually try to have one grammar section that incorporates all of the changes > over the years, like how we added `[C++1z]` on line 873 above. Any appetite > for trying to rearrange like that? C++20 reworded this to the point that there is very little in common, so i feared that the grammar would be particularly rough here. I tried a merge at one point, and it was just pretty messy (since the productions don't particularly well match between them). `type-parameter` in particular ends up being messy, since the leading 'template < param list >' was removed from there. ================ Comment at: clang/test/CXX/temp/temp.arg/temp.arg.template/p3-2a.cpp:60-62 + // A naive individual might expect the following to all fail concept checking, + // but there does not seem to be any requirement to check these in the + // standard, and none of the other implementations do so either. ---------------- aaron.ballman wrote: > I agree that none of the other implementations seems to be checking > constraints here, but I would have guessed that > https://eel.is/c++draft/temp.arg.template#3 was what would trigger checking > the constraints here (the `and for template template-parameters, each of > their corresponding template-parameters matches, recursively.` bit, > specifically). > > Usually the answer to "Am I misreading the standard or are these three > implementations all wrong in the same way?" is "I misread the standard.", but > I'd appreciate some confirmation here. :-) >>Usually the answer to "Am I misreading the standard or are these three >>implementations all wrong in the same way?" is "I misread the standard." This is typically _MY_ response to this as well, so I was hoping @rsmith or @hubert.reinterpretcast could tell me the answer here (and perhaps help write a Core issue if the implementations are all 'right'). CHANGES SINCE LAST ACTION https://reviews.llvm.org/D110641/new/ https://reviews.llvm.org/D110641 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
