[clang] [Clang] Qualified functions can't decay into pointers (PR #90353)

[Vlad Serebrennikov via cfe-commits]

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@@ -71,6 +76,17 @@ namespace cwg712 { // cwg712: partial
 #endif
 }
 
+namespace cwg713 { // cwg713: yes
+static_assert(!__is_const(void()const), "");
+static_assert(!__is_const(void()const&), "");
+// cxx98-error at -1 {{reference qualifiers on functions are a C++11 extension}}
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Endilll wrote:

I think this test and another one later should be hidden behind `#ifdef __cplusplus`

https://github.com/llvm/llvm-project/pull/90353