code: func isGoVoidPtr(t *cc.Type) bool {
  	if t == nil || t.Kind != cc.Ptr {
  		return false
  	}
  	t = t.Base
  	return t.Kind == cc.Void || t.Kind == cc.Struct && len(t.Decls) == 0
  }
docs: // isGoVoidPtr reports whether t is a void* or the Go translation of a void* (*struct{}).