What version of Go are you using (go version)?

$ go version go1.11.2 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

$ go env 
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/lukas/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/lukas/go"
GOPROXY=""
GORACE=""
GOROOT="/usr/local/go"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build545257636=/tmp/go-build -gno-record-gcc-switches"

What did you do?

export GO111MODULE=on in the project folder
go mod download

The repo I am pulling off is a private one and due to having 2FA i can only properly pull using ssh, not https.

What did you expect to see?

I expected it to work and download all dependencies. Apparently git failed pulling, but does not log that into the output.

What did you see instead?

$ go: finding gitlab.com/mygroup/myfolder v0.0.1
$ gitlab.com/mygroup/myfolder v0.0.1 unknown revision

$ go: error loading module requirements

How did you fix it

After pulling the problematic repo manually, I noticed that git failed pulling, so I added one of the git hacks, where it changes https://gitlab.com to git@gitlab.com. This seemed to have fixed the problem. I think go mod should have a more verbose output, or a verbose option where it logs, that git is failing to pull.