func (p *Package) mangleName(n *Name) {
	// When using gccgo variables have to be
	// exported so that they become global symbols
	// that the C code can refer to.
	prefix := "_C"
	if *gccgo && n.IsVar() {
		prefix = "C"
	}
	n.Mangle = prefix + n.Kind + "_" + n.Go
}

func (f *File) isMangledName(s string) bool {
	t, ok := strings.CutPrefix(s, "_C")
	if !ok {
		return false
	}