[clang] [clang][Sema] Allow abstract declarators to specify cv-qualified function types as per CWG1417 (PR #209836)

[Yanzuo Liu via cfe-commits]

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@@ -751,3 +751,13 @@ struct A {
 static_assert(__is_trivial(A), "");
 #endif
 } // namespace cwg1496
+
+namespace cwg1417 { // cwg1417: 24
+  template<typename T> struct S {
+    typedef T F;
+    typedef T *P; // expected-error {{pointer to function type 'void () const' cannot have 'const' qualifier}}
+                  // expected-note@#cwg1417-s {{in instantiation of template class 'cwg1417::S<void () const>' requested here}}
+    typedef T &R; // expected-error {{reference to function type 'void () const' cannot have 'const' qualifier}}
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zwuis wrote:

> - Errors and warnings are placed on the next line after the line they are expecting a diagnostic at, and at the same indentation.

https://github.com/llvm/llvm-project/pull/209836