[clang] [Clang] allow restrict qualifier for array types with pointer types as element types (PR #120896)

[Aaron Ballman via cfe-commits]

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@@ -7409,6 +7409,11 @@ def warn_c23_compat_utf8_string : Warning<
 def note_cxx20_c23_compat_utf8_string_remove_u8 : Note<
   "remove 'u8' prefix to avoid a change of behavior; "
   "Clang encodes unprefixed narrow string literals as UTF-8">;
+def warn_c23_compat_restrict_pointers_to_array : Warning<
+  "'restrict' qualifier on pointers to arrays is incompatible with C17 and earlier">,
+  InGroup<CPre23Compat>, DefaultIgnore;
+def ext_restrict_pointers_to_array_c23 : Extension<
+  "'restrict' qualifier on pointers to arrays is a C23 extension">, InGroup<C23>;
----------------
AaronBallman wrote:

```suggestion
  "'restrict' qualifier on an array of pointers is a C23 extension">, InGroup<C23>;
```

https://github.com/llvm/llvm-project/pull/120896