go type_error ai_generated true

proto: Marshal called with nil message

ID: go/protobuf-marshal-nil-message

Also available as: JSON · Markdown · 中文
80%Fix Rate
87%Confidence
0Evidence
2024-05-02First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
google.golang.org/protobuf v1.26+ active — — —

Root Cause

A typed nil proto message (e.g. (*pb.User)(nil)) was passed to proto.Marshal, or a typed-nil interface was stored and later marshaled.

generic

中文

向 proto.Marshal 传入了类型化的 nil proto 消息（如 (*pb.User)(nil)），或将类型化 nil 接口存储后进行了序列化。

Workarounds

  1. 95% success 
    if msg == nil {
    return errors.New("message is nil")
}
b, err := proto.Marshal(msg)
if err != nil { return err }
  2. 90% success 
    func build() (*pb.User, error) {
    return &pb.User{Name: "a"}, nil // never return (*pb.User)(nil), nil
}

Dead Ends

Common approaches that don't work:

  1. 85% fail

    proto.Marshal returns an error rather than panicking; recover does not catch returned errors.

  2. 80% fail

    The legacy package delegates to the new one and exhibits the same behavior.