[clang] [analyzer] Suppress EnumCastOutOfRange diagnostics in system headers (PR #196323)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,12 @@
+// RUN: %clang_analyze_cc1 \
+// RUN:   -analyzer-checker=core,optin.core.EnumCastOutOfRange \
+// RUN:   -isystem %S/Inputs \
+// RUN:   -verify %s
+
+#include "enum-system-header.h"
+
+void test() {
+  bad_cast(100);
+}
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steakhal wrote:

I don't like that we demonstrate this suppression with a true-positive report.
I think we should motivate the suppression with a genuine false-positive report.

https://github.com/llvm/llvm-project/pull/196323