[libcxx-commits] [libcxx] Make C++ 20 std::midpoint compatible with libc++ (PR #74217)

[Nikolas Klauser via libcxx-commits]

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@@ -51,19 +51,12 @@ _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
     return __a + __half_diff;
 }
 
-
 template <class _TPtr>
-_LIBCPP_HIDE_FROM_ABI constexpr
-enable_if_t<is_pointer_v<_TPtr>
-             && is_object_v<remove_pointer_t<_TPtr>>
-             && ! is_void_v<remove_pointer_t<_TPtr>>
-             && (sizeof(remove_pointer_t<_TPtr>) > 0), _TPtr>
-midpoint(_TPtr __a, _TPtr __b) noexcept
-{
-    return __a + std::midpoint(ptrdiff_t(0), __b - __a);
+_LIBCPP_INLINE_VISIBILITY constexpr enable_if_t<is_object_v<_TPtr> && !is_void_v<_TPtr> && (sizeof(_TPtr) > 0), _TPtr*>
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philnik777 wrote:

While we're modifying this code anyways, let's also refactor the `enable_if_t` to the `enable_if_t<..., int> = 0` variant.

https://github.com/llvm/llvm-project/pull/74217