// Go is a tool for managing Go source code.
//
// Usage:
//
//	go <command> [arguments]
//
// The commands are:
//
//	bug         start a bug report
//	build       compile packages and dependencies
//	clean       remove object files and cached files
//	doc         show documentation for package or symbol
//	env         print Go environment information

// If there isn't one, findInternal returns ok=false.
// Otherwise, findInternal returns ok=true and the index of the "internal".
func findInternal(path string) (index int, ok bool) {
	// Three cases, depending on internal at start/end of string or not.
	// The order matters: we must return the index of the final element,
	// because the final one produces the most restrictive requirement
	// on the importer.
	switch {

			const cgoLdflag = "//go:cgo_ldflag"
			idx := bytes.Index(src, []byte(cgoLdflag))
			for idx >= 0 {
				// We are looking at //go:cgo_ldflag.
				// Find start of line.
				start := bytes.LastIndex(src[:idx], []byte("\n"))
				if start == -1 {
					start = 0
				}

				// Find end of line.
				end := bytes.Index(src[idx:], []byte("\n"))
				if end == -1 {
					end = len(src)
				} else {