libstdc++: Rename template parameter of std::constant_wrapper

This fixes:
FAIL: 17_intro/badnames.cc  -std=gnu++26 (test for excess errors)

libstdc++-v3/ChangeLog:

	* include/std/type_traits (constant_wrapper): Rename template
	parameter to avoid BADNAME.

diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index 26cbbb4fd5ba9e036d83be7fff1fec65da716a93..42a1e7f1732bca2504a20e253b57d5853c969118 100644 (file)
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -4648,12 +4648,12 @@ template<typename _Ret, typename _Fn, typename... _Args>
       }
   };
 
-  template<_CwFixedValue _X, typename>
+  template<_CwFixedValue _Xv, typename>
   struct constant_wrapper : _CwOperators
   {
-    static constexpr const auto& value = _X._M_data;
+    static constexpr const auto& value = _Xv._M_data;
     using type = constant_wrapper;
-    using value_type = typename decltype(_X)::_S_type;
+    using value_type = typename decltype(_Xv)::_S_type;
 
     template<_ConstExprParam _Right>
       constexpr auto