1 files changed, 48 insertions, 0 deletions
diff --git a/src/runtime/race/sched_test.go b/src/runtime/race/sched_test.go
new file mode 100644
index 0000000..a66860c
--- /dev/null
+++ b/src/runtime/race/sched_test.go
@@ -0,0 +1,48 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build race
+
+package race_test
+
+import (
+	"fmt"
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestRandomScheduling(t *testing.T) {
+	// Scheduler is most consistent with GOMAXPROCS=1.
+	// Use that to make the test most likely to fail.
+	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(1))
+	const N = 10
+	out := make([][]int, N)
+	for i := 0; i < N; i++ {
+		c := make(chan int, N)
+		for j := 0; j < N; j++ {
+			go func(j int) {
+				c <- j
+			}(j)
+		}
+		row := make([]int, N)
+		for j := 0; j < N; j++ {
+			row[j] = <-c
+		}
+		out[i] = row
+	}
+
+	for i := 0; i < N; i++ {
+		if !reflect.DeepEqual(out[0], out[i]) {
+			return // found a different order
+		}
+	}
+
+	var buf strings.Builder
+	for i := 0; i < N; i++ {
+		fmt.Fprintf(&buf, "%v\n", out[i])
+	}
+	t.Fatalf("consistent goroutine execution order:\n%v", buf.String())
+}