I just reset my dev env. Then when I tried to run my old go code using go run ., it failed with errors:
# golang.org/x/sys/unix
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/syscall_darwin.1_13.go:29:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.1_13.go:27:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.1_13.go:40:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:28:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:43:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:59:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:75:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:90:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:105:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:121:3: //go:linkname must refer to declared function or variable
../../go/pkg/mod/golang.org/x/sys@v0.0.0-20201119102817-f84b799fce68/unix/zsyscall_darwin_amd64.go:121:3: too many errors
The problem is solved by running this command:
go get -u golang.org/x/sys