erik.pilkington added a comment. In https://reviews.llvm.org/D30837#698305, @EricWF wrote:
> We can't just use an arbitrary allocator type for a number of reasons: > > - You just changed the type of the control block. That's ABI breaking. Ah, I didn't think of that. This new patch only selects `allocator<int>` when _Yp is a function type, which is only permitted as of this patch. > - `allocator<int>` allocates ints, nothing else. Since we only use `allocator<int>` for a rebind, we don't violate this rule. > - It may mean we don't select a valid user specialization of `allocator<Yp>`. In the new patch, `allocator<int>` is only selected if `is_function<_Yp>`, I don't believe that there is any valid user specialization of `std::allocator<FunctionType>`. This is because [namespace.std] p1: > A program may add a template specialization for any standard library template > to namespace std only if [...] the specialization meets the standard library > requirements for the original template [...] In this case, the original template is the default allocator, which is supposed to have overloads of `address` taking a `const_reference` and a `reference` ([allocator.members] p2-3), which will be ambiguous for function types with the given definitions of `const_reference` and `reference`. Is this a valid argument? https://reviews.llvm.org/D30837 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
