Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/compiler-rt/test/tsan/sleep_sync.cc

@@ -0,0 +1,32 @@
+// RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
+#include "test.h"
+
+int X = 0;
+
+void MySleep() {
+  sleep(1);  // the sleep that must appear in the report
+}
+
+void *Thread(void *p) {
+  barrier_wait(&barrier);
+  MySleep();  // Assume the main thread has done the write.
+  X = 42;
+  return 0;
+}
+
+int main() {
+  barrier_init(&barrier, 2);
+  pthread_t t;
+  pthread_create(&t, 0, Thread, 0);
+  X = 43;
+  barrier_wait(&barrier);
+  pthread_join(t, 0);
+  return 0;
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// ...
+// CHECK:   As if synchronized via sleep:
+// CHECK-NEXT:     #0 sleep
+// CHECK-NEXT:     #1 MySleep
+// CHECK-NEXT:     #2 Thread