[libcxx-commits] [PATCH] D131498: [libc++][NFC] Rename the constexpr macros

[Nikolas Klauser via Phabricator via libcxx-commits]

philnik added inline comments.


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Comment at: libcxx/include/__memory/uninitialized_algorithms.h:625
                           __allocator_has_trivial_move_construct<_Alloc, _Type>::value> >
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 _Iter2
+_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_CXX20 _Iter2
 __uninitialized_allocator_move_if_noexcept(_Alloc&, _Iter1 __first1, _Iter1 __last1, _Iter2 __first2) {
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var-const wrote:
> ldionne wrote:
> > For example, is there a reason why this is only constexpr in C++20? Maybe it should be marked as constexpr whenever we have support for C++14 generalized constexpr?
> General question -- for internal functions, should we make them `constexpr` in the lowest language mode possible, or just in the language mode where they are actually used? I'm slightly concerned about overconstraining the implementation, though we can probably always work around that if necessary.
We normally use what works, i.e. the lowest language mode feasible. Don't try to make some function constexpr in C++11 just because it's technically possible. But you might as well do it when the function would work in C++11 constexpr.


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  https://reviews.llvm.org/D131498/new/

https://reviews.llvm.org/D131498