[compiler-rt] [HWASAN] Add test to detected use after free in memcmp (PR #67204)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-compiler-rt-sanitizer

<details>
<summary>Changes</summary>

The plan is to fix memcmp interceptor in HWASAN and remove the unsupported statement at that time. 

---
Full diff: https://github.com/llvm/llvm-project/pull/67204.diff


1 Files Affected:

- (added) compiler-rt/test/sanitizer_common/TestCases/memcmp.cpp (+15) 


``````````diff
diff --git a/compiler-rt/test/sanitizer_common/TestCases/memcmp.cpp b/compiler-rt/test/sanitizer_common/TestCases/memcmp.cpp
new file mode 100644
index 000000000000000..23fe8e2cfe0d620
--- /dev/null
+++ b/compiler-rt/test/sanitizer_common/TestCases/memcmp.cpp
@@ -0,0 +1,15 @@
+// RUN: %clangxx -O0 %s -o %t && %run %t
+// XFAIL: *
+// UNSUPPORTED: lsan, ubsan
+// FIXME: HWASAN should work when we have intercepptors.
+// UNSUPPORTED: hwasan
+
+#include <cstring>
+#include <cstdio>
+
+int main(int argc, char** argv) {
+  int *x = new int(7);
+  delete x;
+  // Trigger use after free error.
+  return memcmp(x, &argc, sizeof(int)) == 0 ? 1 : 0;
+}
\ No newline at end of file

``````````

</details>


https://github.com/llvm/llvm-project/pull/67204