diff --git a/src/cmd/go/go_test.go b/src/cmd/go/go_test.go
index 60c0c6f..d047596 100644
--- a/src/cmd/go/go_test.go
+++ b/src/cmd/go/go_test.go
@@ -4044,7 +4044,7 @@
 		cmd.Env = env
 		out, err := cmd.CombinedOutput()
 		if err != nil {
-			t.Fatal(err)
+			t.Fatalf("%s env GOROOT: %v, %s", exe, err, out)
 		}
 		goroot, err := filepath.EvalSymlinks(strings.TrimSpace(string(out)))
 		if err != nil {