func (st *state) cloneSuffix(a AST) AST {
	i := 0
	if len(st.str) > 1 && st.str[0] == '.' && (isLower(st.str[1]) || st.str[1] == '_') {
		i += 2
		for len(st.str) > i && (isLower(st.str[i]) || st.str[i] == '_') {
			i++
		}
	}
	for len(st.str) > i+1 && st.str[i] == '.' && isDigit(st.str[i+1]) {
		i += 2
		for len(st.str) > i && isDigit(st.str[i]) {
			i++
		}
	}
	suffix := st.str[:i]
	st.advance(i)
	return &Clone{Base: a, Suffix: suffix}
}
func (st *state) cloneSuffix(a AST) AST {
	i := 0
	if len(st.str) > 1 && st.str[0] == '.' && (isLower(st.str[1]) || st.str[1] == '_') {
		i += 2
		for len(st.str) > i && (isLower(st.str[i]) || st.str[i] == '_') {
			i++
		}
	}
	for len(st.str) > i+1 && st.str[i] == '.' && isDigit(st.str[i+1]) {
		i += 2
		for len(st.str) > i && isDigit(st.str[i]) {
			i++
		}
	}
	suffix := st.str[:i]
	st.advance(i)
	return &Clone{Base: a, Suffix: suffix}
}
// Recognize a clone suffix.  These are not part of the mangling API,
// but are added by GCC when cloning functions.