1 files changed, 41 insertions, 0 deletions
diff --git a/lib/tsan/output_tests/race_on_mutex.c b/lib/tsan/output_tests/race_on_mutex.c
new file mode 100644
index 000000000000..45c75be782d1
--- /dev/null
+++ b/lib/tsan/output_tests/race_on_mutex.c
@@ -0,0 +1,41 @@
+#include <pthread.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <unistd.h>
+
+pthread_mutex_t Mtx;
+int Global;
+
+void *Thread1(void *x) {
+  pthread_mutex_init(&Mtx, 0);
+  pthread_mutex_lock(&Mtx);
+  Global = 42;
+  pthread_mutex_unlock(&Mtx);
+  return NULL;
+}
+
+void *Thread2(void *x) {
+  usleep(1000000);
+  pthread_mutex_lock(&Mtx);
+  Global = 43;
+  pthread_mutex_unlock(&Mtx);
+  return NULL;
+}
+
+int main() {
+  pthread_t t[2];
+  pthread_create(&t[0], NULL, Thread1, NULL);
+  pthread_create(&t[1], NULL, Thread2, NULL);
+  pthread_join(t[0], NULL);
+  pthread_join(t[1], NULL);
+  pthread_mutex_destroy(&Mtx);
+  return 0;
+}
+
+// CHECK:      WARNING: ThreadSanitizer: data race
+// CHECK-NEXT:   Read of size 1 at {{.*}} by thread 2:
+// CHECK-NEXT:     #0 pthread_mutex_lock {{.*}} ({{.*}})
+// CHECK-NEXT:     #1 Thread2 {{.*}}race_on_mutex.c:19{{(:3)?}} ({{.*}})
+// CHECK-NEXT:   Previous write of size 1 at {{.*}} by thread 1:
+// CHECK-NEXT:     #0 pthread_mutex_init {{.*}} ({{.*}})
+// CHECK-NEXT:     #1 Thread1 {{.*}}race_on_mutex.c:10{{(:3)?}} ({{.*}})