Why is it "exit status 1"?

[webees]

api/user.go

// @summary 用户注册接口
func (a *userApi) SignUp(r *ghttp.Request) {
        // Some codes
}

go.mod

$ go mod tidy

module thash

go 1.15

require (
    github.com/gogf/gf v1.15.3
    github.com/gogf/swagger v1.2.0
    github.com/kr/text v0.2.0 // indirect
    github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
    golang.org/x/net v0.0.0-20210220033124-5f55cee0dc0d // indirect
    golang.org/x/sys v0.0.0-20210220050731-9a76102bfb43 // indirect
    golang.org/x/text v0.3.5 // indirect
    golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
    gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
    gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
)

gf -v

GoFrame CLI Tool v1.15.0, https://goframe.org
Install Path: C:\Windows\gf.exe
Build Detail:
  Go Version:  go1.15.5
  GF Version:  v1.15.1
  Git Commit:  3b3701b7e8aa5fcc9f12ffc0f567ffce62d6308d
  Build Time:  2021-01-19 15:21:28

gf swagger --pack

• No swagger.json generated

  2021-02-20 19:11:12.916 producing swagger files...
  go: found github.com/swaggo/swag/cmd/swag in github.com/swaggo/swag v1.7.0
  go: golang.org/x/text upgrade => v0.3.5
  go: golang.org/x/tools upgrade => v0.1.0
  go: golang.org/x/net upgrade => v0.0.0-20210220033124-5f55cee0dc0d
  go: github.com/russross/blackfriday/v2 upgrade => v2.1.0
  go: github.com/go-openapi/spec upgrade => v0.20.3       
  go: gopkg.in/yaml.v2 upgrade => v2.4.0
  go: golang.org/x/sys upgrade => v0.0.0-20210220050731-9a76102bfb43
  go: github.com/go-openapi/jsonpointer upgrade => v0.19.5
  go: github.com/mailru/easyjson upgrade => v0.7.7      
  go: github.com/cpuguy83/go-md2man/v2 upgrade => v2.0.0
  go: github.com/go-openapi/swag upgrade => v0.19.14
  go: github.com/go-openapi/jsonreference upgrade => v0.19.5
  2021-02-20 19:11:15.094 'swag' �����ڲ����ⲿ���Ҳ���ǿ����еij���
  ���������ļ���
  exit status 1

The following message should be displayed

$ swag init
2021/02/21 18:21:13 Generate swagger docs....
2021/02/21 18:21:13 Generate general API Info, search dir:./
2021/02/21 18:21:21 ParseComment error in file app\api\user.go :cannot find type definition: model.UserApiSignUpReq