gdb golang，如何打印基类信息？

When I debug protoc-gen-go, I want to print generator.FileDescriptor's base class infomation, its base class is github.com/golang/protobuf/protoc-gen-go/descriptor.FileDescriptorProto.

gdb print type:

ptype file

gdb outputs:

type = struct generator.FileDescriptor {
struct github.com/golang/protobuf/protoc-gen-go/descriptor.FileDescriptorProto **github.com/golang/protobuf/protoc-gen-go/descriptor.FileDescriptorProto;
struct []*generator.Descriptor desc;
struct []*generator.EnumDescriptor enum;
struct []*generator.ExtensionDescriptor ext;
struct []*generator.ImportedDescriptor imp;
map[string]*github.com/golang/protobuf/protoc-gen-go/descriptor.SourceCodeInfo_Location comments;
map[generator.Object][]generator.symbol exported;
int index;
bool proto3;

} *

now I want to print the baseclass descriptor.FileDescriptorProto info, how to do that? I am a beginner in golang programming. I tried following manners, but neither workerd.

ptype file.github.com/golang/protobuf/protoc-gen-go/descriptor.FileDescriptorProto
ptype file.*github.com/golang/protobuf/protoc-gen-go/descriptor.FileDescriptorProto
ptype file.FileDescriptorProto
ptype file.*FileDescriptorProto
...

how do you print the base class info of file *FileDescriptor, this class is defined in package generator.

Thanks in advance!