libgo: update to Go1.12beta2

    
    Reviewed-on: https://go-review.googlesource.com/c/158019

gotools/:
	* Makefile.am (go_cmd_vet_files): Update for Go1.12beta2 release.
	(GOTOOLS_TEST_TIMEOUT): Increase to 600.
	(check-runtime): Export LD_LIBRARY_PATH before computing GOARCH
	and GOOS.
	(check-vet): Copy golang.org/x/tools into check-vet-dir.
	* Makefile.in: Regenerate.

gcc/testsuite/:
	* go.go-torture/execute/names-1.go: Stop using debug/xcoff, which
	is no longer externally visible.

From-SVN: r268084

2 files changed, 5 insertions, 9 deletions

diff --git a/libgo/go/sync/map.go b/libgo/go/sync/map.go
index c4a0dc4..c6aa308 100644
--- a/libgo/go/sync/map.go
+++ b/libgo/go/sync/map.go
@@ -167,18 +167,14 @@ func (m *Map) Store(key, value interface{}) {
 // If the entry is expunged, tryStore returns false and leaves the entry
 // unchanged.
 func (e *entry) tryStore(i *interface{}) bool {
-	p := atomic.LoadPointer(&e.p)
-	if p == expunged {
-		return false
-	}
 	for {
-		if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
-			return true
-		}
-		p = atomic.LoadPointer(&e.p)
+		p := atomic.LoadPointer(&e.p)
 		if p == expunged {
 			return false
 		}
+		if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
+			return true
+		}
 	}
 }
 
diff --git a/libgo/go/sync/runtime.go b/libgo/go/sync/runtime.go
index be16bcc..b6b9e48 100644
--- a/libgo/go/sync/runtime.go
+++ b/libgo/go/sync/runtime.go
@@ -54,7 +54,7 @@ func init() {
 }
 
 // Active spinning runtime support.
-// runtime_canSpin returns true is spinning makes sense at the moment.
+// runtime_canSpin reports whether spinning makes sense at the moment.
 func runtime_canSpin(i int) bool
 
 // runtime_doSpin does active spinning.