That looks like a clear-cut bug in protoc-gen-go to me: https://github.com/golang/protobuf/issues/new
I suspect there's some issue where it recognizes it is inside a proto3 message, so it generates scalar fields without a pointer. But only proto2 messages are allowed to have extensions (in this case, descriptor.proto is still syntax = "proto2"), so it needs to special-case extension fields. ---- *Josh Humphries* [email protected] On Mon, Sep 25, 2017 at 5:05 AM, Tomoyuki Saito <[email protected]> wrote: > When trying to use extensions with a parent message, a build error happens > with a message like "cannot convert nil to type bool." > > In generator.go > <https://github.com/golang/protobuf/blob/130e6b02ab059e7b717a096f397c5b60111cae74/protoc-gen-go/generator/generator.go#L1678>, > I'm expecting the extension fields should reach needsStar() > <https://github.com/golang/protobuf/blob/130e6b02ab059e7b717a096f397c5b60111cae74/protoc-gen-go/generator/generator.go#L1678>, > but actually they won't because they have a parent and the parent's > syntax is proto3 > <https://github.com/golang/protobuf/blob/130e6b02ab059e7b717a096f397c5b60111cae74/protoc-gen-go/generator/generator.go#L1674> > . > Is this working as expected? Or, is this a bug? > > Versions > > protoc version: libprotoc 3.3.2 > golang/protobuf: using the current master https://github.com/ > golang/protobuf/tree/130e6b02ab059e7b717a096f397c5b60111cae74 > > Commands for reproducing an issue > ~/go/src/github.com/occho/protobuf-test/test$ pwd > <home>/go/src/github.com/occho/protobuf-test/test > ~/go/src/github.com/occho/protobuf-test/test$ ls > test.proto > ~/go/src/github.com/occho/protobuf-test/test$ protoc > --go_out=${GOPATH}/src test.proto > ~/go/src/github.com/occho/protobuf-test/test$ go build > # github.com/occho/protobuf-test/test > ./test.pb.go:41:23: cannot convert nil to type bool > ./test.pb.go:50:25: cannot convert nil to type string > ./test.pb.go:59:24: cannot convert nil to type int32 > > > File: test.proto > syntax = "proto3"; > > package test; > > import "google/protobuf/descriptor.proto"; > > option go_package = "github.com/occho/protobuf-test/test"; > > message Namespace { > extend google.protobuf.FieldOptions { > bool namespace_bool = 50001; > string namespace_string = 50002; > int32 namespace_int32 = 50003; > } > } > > extend google.protobuf.FieldOptions { > bool my_bool = 51001; > string my_string = 51002; > int32 my_int32 = 51003; > } > > Generated file: test.pb.go > // Code generated by protoc-gen-go. DO NOT EDIT. > // source: test.proto > > /* > Package test is a generated protocol buffer package. > > It is generated from these files: > test.proto > > It has these top-level messages: > Namespace > */ > package test > > import proto "github.com/golang/protobuf/proto" > import fmt "fmt" > import math "math" > import google_protobuf "github.com/golang/protobuf/ > protoc-gen-go/descriptor" > > // Reference imports to suppress errors if they are not otherwise used. > var _ = proto.Marshal > var _ = fmt.Errorf > var _ = math.Inf > > // This is a compile-time assertion to ensure that this generated file > // is compatible with the proto package it is being compiled against. > // A compilation error at this line likely means your copy of the > // proto package needs to be updated. > const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package > > type Namespace struct { > } > > func (m *Namespace) Reset() { *m = Namespace{} } > func (m *Namespace) String() string { return > proto.CompactTextString(m) } > func (*Namespace) ProtoMessage() {} > func (*Namespace) Descriptor() ([]byte, []int) { return fileDescriptor0, > []int{0} } > > var E_Namespace_NamespaceBool = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (bool)(nil), > Field: 50001, > Name: "test.Namespace.namespace_bool", > Tag: "varint,50001,opt,name=namespace_bool,json=namespaceBool", > Filename: "test.proto", > } > > var E_Namespace_NamespaceString = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (string)(nil), > Field: 50002, > Name: "test.Namespace.namespace_string", > Tag: "bytes,50002,opt,name=namespace_string,json= > namespaceString", > Filename: "test.proto", > } > > var E_Namespace_NamespaceInt32 = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (int32)(nil), > Field: 50003, > Name: "test.Namespace.namespace_int32", > Tag: "varint,50003,opt,name=namespace_int32,json= > namespaceInt32", > Filename: "test.proto", > } > > var E_MyBool = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (*bool)(nil), > Field: 51001, > Name: "test.my_bool", > Tag: "varint,51001,opt,name=my_bool,json=myBool", > Filename: "test.proto", > } > > var E_MyString = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (*string)(nil), > Field: 51002, > Name: "test.my_string", > Tag: "bytes,51002,opt,name=my_string,json=myString", > Filename: "test.proto", > } > > var E_MyInt32 = &proto.ExtensionDesc{ > ExtendedType: (*google_protobuf.FieldOptions)(nil), > ExtensionType: (*int32)(nil), > Field: 51003, > Name: "test.my_int32", > Tag: "varint,51003,opt,name=my_int32,json=myInt32", > Filename: "test.proto", > } > > func init() { > proto.RegisterType((*Namespace)(nil), "test.Namespace") > proto.RegisterExtension(E_Namespace_NamespaceBool) > proto.RegisterExtension(E_Namespace_NamespaceString) > proto.RegisterExtension(E_Namespace_NamespaceInt32) > proto.RegisterExtension(E_MyBool) > proto.RegisterExtension(E_MyString) > proto.RegisterExtension(E_MyInt32) > } > > func init() { proto.RegisterFile("test.proto", fileDescriptor0) } > > var fileDescriptor0 = []byte{ > // 267 bytes of a gzipped FileDescriptorProto > 0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, > 0x2a, 0x49, 0x2d, 0x2e, > 0xd1, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0x01, 0xb1, 0xa5, 0x14, > 0xd2, 0xf3, 0xf3, 0xd3, > 0x73, 0x52, 0xf5, 0xc1, 0x62, 0x49, 0xa5, 0x69, 0xfa, 0x29, 0xa9, 0xc5, > 0xc9, 0x45, 0x99, 0x05, > 0x25, 0xf9, 0x45, 0x10, 0x75, 0x4a, 0x2f, 0x19, 0xb9, 0x38, 0xfd, 0x12, > 0x73, 0x53, 0x8b, 0x0b, > 0x12, 0x93, 0x53, 0x8d, 0xdc, 0xb8, 0xf8, 0xf2, 0x60, 0x9c, 0xf8, 0xa4, > 0xfc, 0xfc, 0x1c, 0x21, > 0x59, 0x3d, 0x88, 0x11, 0x7a, 0x30, 0x23, 0xf4, 0xdc, 0x32, 0x53, 0x73, > 0x52, 0xfc, 0x0b, 0x4a, > 0x32, 0xf3, 0xf3, 0x8a, 0x25, 0x2e, 0xb6, 0x31, 0x2b, 0x30, 0x6a, 0x70, > 0x04, 0xf1, 0xc2, 0xb5, > 0x39, 0xe5, 0xe7, 0xe7, 0x18, 0x79, 0x71, 0x09, 0x20, 0xcc, 0x29, 0x2e, > 0x29, 0xca, 0xcc, 0x4b, > 0x27, 0x64, 0xd2, 0x25, 0xb0, 0x49, 0x9c, 0x41, 0xfc, 0x70, 0x8d, 0xc1, > 0x60, 0x7d, 0x46, 0x1e, > 0x5c, 0x08, 0xa1, 0xf8, 0xcc, 0xbc, 0x12, 0x63, 0x23, 0x42, 0x46, 0x5d, > 0x06, 0x1b, 0xc5, 0x1a, > 0x84, 0xf0, 0x8b, 0x27, 0x48, 0x9b, 0x95, 0x05, 0x17, 0x7b, 0x6e, 0x25, > 0x51, 0xde, 0xda, 0xd9, > 0x07, 0xf1, 0x16, 0x5b, 0x6e, 0x25, 0xc8, 0x3f, 0x56, 0x36, 0x5c, 0x9c, > 0xb9, 0x95, 0x44, 0x7a, > 0x64, 0x57, 0x1f, 0xc4, 0x23, 0x1c, 0xb9, 0x95, 0x10, 0x1f, 0x58, 0x59, > 0x71, 0x71, 0xe4, 0x56, > 0x12, 0xe7, 0xf4, 0xdd, 0x7d, 0x10, 0xa7, 0xb3, 0xe7, 0x56, 0x82, 0xdd, > 0xec, 0xa4, 0x1a, 0xa5, > 0x9c, 0x9e, 0x59, 0x92, 0x51, 0x9a, 0xa4, 0x97, 0x9c, 0x9f, 0xab, 0x9f, > 0x9f, 0x9c, 0x9c, 0x91, > 0x0f, 0x8f, 0x4d, 0x5d, 0x50, 0x1c, 0xeb, 0x83, 0x88, 0x24, 0x36, 0xb0, > 0x98, 0x31, 0x20, 0x00, > 0x00, 0xff, 0xff, 0x6c, 0xa5, 0xed, 0x4d, 0x03, 0x02, 0x00, 0x00, > } > > > > -- > You received this message because you are subscribed to the Google Groups > "Protocol Buffers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/protobuf. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
