func getStructCodec(t reflect.Type) (*structCodec, error) {
	structCodecsMutex.Lock()
	defer structCodecsMutex.Unlock()
	return getStructCodecLocked(t)
}
func getStructCodec(t reflect.Type) (*structCodec, error) {
	structCodecsMutex.Lock()
	defer structCodecsMutex.Unlock()
	return getStructCodecLocked(t)
}
// getStructCodec returns the structCodec for the given struct type.