func init() { … } var cftypeFix … // Old state: // // type CFTypeRef unsafe.Pointer // // New state: // // type CFTypeRef uintptr // // and similar for other *Ref types. // This fix finds nils initializing these types and replaces the nils with 0s. func cftypefix(f *ast.File) bool { … } // typefix replaces nil with 0 for all nils whose type, when passed to badType, returns true. func typefix(f *ast.File, badType func(string) bool) bool { … }