[clang] [Clang] Fix parsing of reversible type traits in template arguments (PR #95969)

[Mital Ashok via cfe-commits]

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@@ -141,3 +141,15 @@ namespace r360308_regression {
     return a == b;
   }
 }
+
+namespace GH95598 {
+template<typename _Tp, bool _IsPtr = __is_pointer(_Tp)>
+struct __is_pointer {};
+// expected-warning at -1 {{keyword '__is_pointer' will be made available as an identifier for the remainder of the translation unit}}
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MitalAshok wrote:

@zygoloid https://github.com/itanium-cxx-abi/cxx-abi/blob/07427ac5b6ff0799c47e8c754609cf8220c05cc0/gcc-tinfo2.cc#L373 :(

https://github.com/llvm/llvm-project/pull/95969