[libcxx-commits] [libcxx] [libc++] Extend __default_three_way_comparator to any types that only implements operator<=> (PR #157602)

[Louis Dionne via libcxx-commits]

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@@ -2521,6 +2521,7 @@ _LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST(_LIBCPP_DECLARE, wchar_t)
 #  endif
 #  undef _LIBCPP_DECLARE
 
+#  if _LIBCPP_STD_VER <= 17 || !__has_builtin(__builtin_lt_synthesises_from_spaceship)
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ldionne wrote:

It's nice that the builtin basically removes the need for this special case.

https://github.com/llvm/llvm-project/pull/157602