[libcxx-commits] [libcxx] [libc++] Support more GCC 15 type_traits builtins (PR #137871)

[Roland McGrath via libcxx-commits]

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@@ -20,8 +20,18 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 #if __has_builtin(__add_lvalue_reference)
 
+#  if defined(_LIBCPP_COMPILER_GCC)
+template <class _Tp>
+struct __add_lvalue_reference_gcc {
+  using type = __add_lvalue_reference(_Tp);
+};
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frobtech wrote:

If there is no window where both 14 and 15 work, then you make it impossible for people to upgrade.  I need to upgrade to a fixed libc++ today so that I can upgrade to GCC 15 tomorrow.  I can't upgrade to GCC 15 today because I need first land an upgraded libc++.

https://github.com/llvm/llvm-project/pull/137871