[clang] [Wunsafe-buffer-usage] Fix false positives in handling enums (PR #117370)

[via cfe-commits]

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@@ -39,6 +39,23 @@ void constant_idx_unsafe(unsigned idx) {
   buffer[10] = 0;       // expected-note{{used in buffer access here}}
 }
 
+enum FooEnum {
+  A = 0,
+  B = 1,
+  C = 2,
+  D
+};
+
+void constant_enum_safe() {
+  int buffer[FooEnum::D] = { 0, 1, 2 };
+  buffer[C] = 0; // no-warning
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mxms0 wrote:

Good suggestion, fixed :)

https://github.com/llvm/llvm-project/pull/117370