stdPackages: stdPackages,
			importMap:   importMap,
			importDir:   importDir,
		}
		imports, _ = listCache.LoadOrStore(name, imports)
	}

	li := imports.(listImports)
	w.stdPackages = li.stdPackages
	w.importDir = li.importDir
	w.importMap = li.importMap
}

// listEnv returns the process environment to use when invoking 'go list' for
// the given context.
func listEnv(c *build.Context) []string {

		stsOpts.DurationSeconds = int(expiryDuration.Seconds())
	}
	li, err := cr.NewSTSAssumeRole(stsEndpoint, stsOpts)
	if err != nil {
		log.Fatalf("Error initializing STS Identity: %v", err)
	}

	stsEndpointURL, err := url.Parse(stsEndpoint)
	if err != nil {
		log.Fatalf("Error parsing sts endpoint: %v", err)
	}

	opts := &minio.Options{
		Creds:  li,
		Secure: stsEndpointURL.Scheme == "https",
	}

	go func() {
		var buf bytes.Buffer
		enc := json.NewEncoder(&buf)
		for {
			select {
			case <-ctx.Done():
				return
			case li := <-logCh:
				if !li.SendLog(node, logKind) {
					continue
				}
				buf.Reset()
				if err := enc.Encode(li); err != nil {
					continue
				}
				select {
				case <-ctx.Done():
					return

		if !strings.HasPrefix(arg, "-O") {
			nargs = append(nargs, arg)
		}
	}

	// Force -O0 optimization and append extra arguments, but keep the
	// trailing "-" at the end.
	li := len(nargs) - 1
	last := nargs[li]
	nargs[li] = "-O0"
	nargs = append(nargs, extraArgs...)
	nargs = append(nargs, last)

	if *debugGcc {
		fmt.Fprintf(os.Stderr, "$ %s <<EOF\n", strings.Join(nargs, " "))