[开发工具]go get -u 出错git submodule update --init --recursive cannot be used without a working tree.

一直报错cannot be used without a working tree.

C:\Users\Administrator>go get -u github.com/visualfc/gocode
# cd E:\dev_tools\go1.15\mygo_path\src\golang.org\x\mod; git submodule update --init --recursive
fatal: E:/dev_tools/Git/mingw64/libexec/git-core\git-submodule cannot be used without a working tree.
package golang.org/x/mod/modfile: exit status 1

知道切换为国内源

C:\Users\Administrator>go env -w ?GO111MODULE=on

C:\Users\Administrator>go env ?-w GOPROXY=https://goproxy.cn,direct

C:\Users\Administrator>
C:\Users\Administrator>
C:\Users\Administrator>go get -u github.com/visualfc/gocode
go: downloading github.com/visualfc/gocode v1.3.2
go: github.com/visualfc/gocode upgrade => v1.3.2
go: downloading github.com/visualfc/gotools v1.3.4
go: downloading github.com/visualfc/fastmod v1.3.7
go: golang.org/x/tools upgrade => v0.1.7
go: golang.org/x/mod upgrade => v0.5.1
go: golang.org/x/xerrors upgrade => v0.0.0-20200804184101-5ec99f83aff1
go: github.com/visualfc/gotools upgrade => v1.3.6
go: downloading github.com/visualfc/gotools v1.3.6
go: downloading golang.org/x/tools v0.1.7
go: downloading golang.org/x/mod v0.5.1