libgo: Update to weekly.2012-03-04 release.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@185010 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 20 insertions, 15 deletions

diff --git a/libgo/go/sync/example_test.go b/libgo/go/sync/example_test.go
index 1424b1e79e6..15649240035 100644
--- a/libgo/go/sync/example_test.go
+++ b/libgo/go/sync/example_test.go
@@ -5,6 +5,7 @@
 package sync_test
 
 import (
+	"fmt"
 	"net/http"
 	"sync"
 )
@@ -32,3 +33,22 @@ func ExampleWaitGroup() {
 	// Wait for all HTTP fetches to complete.
 	wg.Wait()
 }
+
+func ExampleOnce() {
+	var once sync.Once
+	onceBody := func() {
+		fmt.Printf("Only once\n")
+	}
+	done := make(chan bool)
+	for i := 0; i < 10; i++ {
+		go func() {
+			once.Do(onceBody)
+			done <- true
+		}()
+	}
+	for i := 0; i < 10; i++ {
+		<-done
+	}
+	// Output:
+	// Only once
+}
diff --git a/libgo/go/sync/waitgroup.go b/libgo/go/sync/waitgroup.go
index 3e7d9d3c8f4..0165b1ffb2b 100644
--- a/libgo/go/sync/waitgroup.go
+++ b/libgo/go/sync/waitgroup.go
@@ -11,21 +11,6 @@ import "sync/atomic"
 // goroutines to wait for.  Then each of the goroutines
 // runs and calls Done when finished.  At the same time,
 // Wait can be used to block until all goroutines have finished.
-//
-// For example:
-//
-//   for i := 0; i < n; i++ {
-//       if !condition(i) {
-//           continue
-//       }
-//       wg.Add(1)
-//       go func() {
-//           // Do something.
-//           wg.Done()
-//       }()
-//   }
-//   wg.Wait()
-// 
 type WaitGroup struct {
 	m       Mutex
 	counter int32