1 files changed, 27 insertions, 0 deletions
diff --git a/lib/tsan/lit_tests/user_malloc.cc b/lib/tsan/lit_tests/user_malloc.cc
new file mode 100644
index 0000000000000..0be6d54fb13a7
--- /dev/null
+++ b/lib/tsan/lit_tests/user_malloc.cc
@@ -0,0 +1,27 @@
+// RUN: %clangxx_tsan -O1 %s -o %t && %t 2>&1 | FileCheck %s
+#include <stdio.h>
+
+// defined by tsan.
+extern "C" void *__interceptor_malloc(unsigned long size);
+extern "C" void __interceptor_free(void *p);
+
+extern "C" void *malloc(unsigned long size) {
+  static int first = 0;
+  if (__sync_lock_test_and_set(&first, 1) == 0)
+    printf("user malloc\n");
+  return __interceptor_malloc(size);
+}
+
+extern "C" void free(void *p) {
+  __interceptor_free(p);
+}
+
+int main() {
+  volatile char *p = (char*)malloc(10);
+  p[0] = 0;
+  free((void*)p);
+}
+
+// CHECK: user malloc
+// CHECK-NOT: ThreadSanitizer
+