diff --git a/src/pkg/go/build/path.go b/src/pkg/go/build/path.go
index 5b4d9243e67..7a281800c28 100644
--- a/src/pkg/go/build/path.go
+++ b/src/pkg/go/build/path.go
@@ -57,7 +57,7 @@ func (t *Tree) PkgDir() string {
 func (t *Tree) BinDir() string {
 	if t.Goroot {
 		if gobin := os.Getenv("GOBIN"); gobin != "" {
-			return gobin
+			return filepath.Clean(gobin)
 		}
 	}
 	return filepath.Join(t.Path, "bin")