// Builder returns the empty string.
func Builder() string {
	return os.Getenv("GO_BUILDER_NAME")
}

// HasGoBuild reports whether the current system can build programs with “go build”
// and then run them with os.StartProcess or exec.Command.
func HasGoBuild() bool {
	if os.Getenv("GO_GCFLAGS") != "" {
		// It's too much work to require every caller of the go command

	if err != nil {
		log.Fatal(err)
	}
	testTmpDir = dir
	if !*testWork {
		defer removeAll(testTmpDir)
	}

	testGOCACHE, _ = cache.DefaultDir()
	if testenv.HasGoBuild() {
		testBin = filepath.Join(testTmpDir, "testbin")
		if err := os.Mkdir(testBin, 0777); err != nil {
			log.Fatal(err)
		}
		testGo = filepath.Join(testBin, "go"+exeSuffix)
		gotool, err := testenv.GoTool()