[clang] [DO not merge] demo test for https://github.com/llvm/llvm-project/pull/140529 (PR #140602)

[Vitaly Buka via cfe-commits]

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@@ -0,0 +1,37 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsanitize=signed-integer-overflow -fsanitize-ignorelist=%t/src.ignorelist -emit-llvm %t/test1.c -o - | FileCheck %s -check-prefix=CHECK-ALLOWLIST
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vitalybuka wrote:

It's not going to hurt to test all 2 files for 3 cases

https://github.com/llvm/llvm-project/pull/140602