1 files changed, 13 insertions, 0 deletions
diff --git a/libgo/go/sync/mutex_test.go b/libgo/go/sync/mutex_test.go
index d0e048ed7a4..f5c20ca49b4 100644
--- a/libgo/go/sync/mutex_test.go
+++ b/libgo/go/sync/mutex_test.go
@@ -89,3 +89,16 @@ func BenchmarkContendedMutex(b *testing.B) {
 	<-c
 	<-c
 }
+
+func TestMutexPanic(t *testing.T) {
+	defer func() {
+		if recover() == nil {
+			t.Fatalf("unlock of unlocked mutex did not panic")
+		}
+	}()
+
+	var mu Mutex
+	mu.Lock()
+	mu.Unlock()
+	mu.Unlock()
+}