Merge tag 'upstream/1.4' into debian-experimental

* tag 'upstream/1.4':
  Imported Upstream version 1.4

1 files changed, 134 insertions, 0 deletions

diff --git a/src/runtime/race/testdata/rwmutex_test.go b/src/runtime/race/testdata/rwmutex_test.go
new file mode 100644
index 000000000..85cb5df3c
--- /dev/null
+++ b/src/runtime/race/testdata/rwmutex_test.go
@@ -0,0 +1,134 @@
+// Copyright 2012 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.
+
+package race_test
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestRaceMutexRWMutex(t *testing.T) {
+	var mu1 sync.Mutex
+	var mu2 sync.RWMutex
+	var x int16 = 0
+	ch := make(chan bool, 2)
+	go func() {
+		mu1.Lock()
+		defer mu1.Unlock()
+		x = 1
+		ch <- true
+	}()
+	go func() {
+		mu2.Lock()
+		x = 2
+		mu2.Unlock()
+		ch <- true
+	}()
+	<-ch
+	<-ch
+}
+
+func TestNoRaceRWMutex(t *testing.T) {
+	var mu sync.RWMutex
+	var x, y int64 = 0, 1
+	ch := make(chan bool, 2)
+	go func() {
+		mu.Lock()
+		defer mu.Unlock()
+		x = 2
+		ch <- true
+	}()
+	go func() {
+		mu.RLock()
+		y = x
+		mu.RUnlock()
+		ch <- true
+	}()
+	<-ch
+	<-ch
+}
+
+func TestRaceRWMutexMultipleReaders(t *testing.T) {
+	var mu sync.RWMutex
+	var x, y int64 = 0, 1
+	ch := make(chan bool, 3)
+	go func() {
+		mu.Lock()
+		defer mu.Unlock()
+		x = 2
+		ch <- true
+	}()
+	go func() {
+		mu.RLock()
+		y = x + 1
+		mu.RUnlock()
+		ch <- true
+	}()
+	go func() {
+		mu.RLock()
+		y = x + 2
+		mu.RUnlock()
+		ch <- true
+	}()
+	<-ch
+	<-ch
+	<-ch
+	_ = y
+}
+
+func TestNoRaceRWMutexMultipleReaders(t *testing.T) {
+	var mu sync.RWMutex
+	x := int64(0)
+	ch := make(chan bool, 3)
+	go func() {
+		mu.Lock()
+		defer mu.Unlock()
+		x = 2
+		ch <- true
+	}()
+	go func() {
+		mu.RLock()
+		y := x + 1
+		_ = y
+		mu.RUnlock()
+		ch <- true
+	}()
+	go func() {
+		mu.RLock()
+		y := x + 2
+		_ = y
+		mu.RUnlock()
+		ch <- true
+	}()
+	<-ch
+	<-ch
+	<-ch
+}
+
+func TestNoRaceRWMutexTransitive(t *testing.T) {
+	var mu sync.RWMutex
+	x := int64(0)
+	ch := make(chan bool, 2)
+	go func() {
+		mu.RLock()
+		_ = x
+		mu.RUnlock()
+		ch <- true
+	}()
+	go func() {
+		time.Sleep(1e7)
+		mu.RLock()
+		_ = x
+		mu.RUnlock()
+		ch <- true
+	}()
+	time.Sleep(2e7)
+	mu.Lock()
+	x = 42
+	mu.Unlock()
+	<-ch
+	<-ch
+}