[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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@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -std=c23 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -std=c17 -fsyntax-only -pedantic -verify=pedantic %s
+// RUN: %clang_cc1 -std=c17 -fsyntax-only -Wpre-c2x-compat -verify=pre-c2x-compat %s
+
+typedef int (*T1)[2];
+restrict T1 t1;         // pedantic-warning {{'restrict' qualifier on pointers to arrays is a C23 extension}} \
+                        // pre-c2x-compat-warning {{'restrict' qualifier on pointers to arrays is incompatible with C17 and earlier}}
+
+typedef int *T2[2];
+restrict T2 t2;         // pedantic-warning {{'restrict' qualifier on pointers to arrays is a C23 extension}} \
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AaronBallman wrote:

This diagnostic wording is incorrect: it's not a pointer to an array, it's an array of pointers. The diagnostic firing on this code is correct, however.

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