GitLab runner cannot find build directory on windows due to wrong use of slashes

I have tried to run builds on my windows machine, but the following error occurs:

gitlab-ci-multi-runner 0.7.2 (998cf5d)
Using Docker executor with image gcc ...
Pulling docker image gitlab/gitlab-runner:cache ...
Pulling docker image gitlab/gitlab-runner:build ...
Pulling docker image gcc:latest ...

Running on runner-f977de80-project-744912-concurrent-0 via MY-PC...
Cloning repository...
Cloning into '/builds/corneyl/cproject'...
Checking out 0e8645d2 as master...
Note: checking out '0e8645d2f0b18230f6b442714e58a2b13432f4d3'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by performing another checkout.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -b with the checkout command again. Example:

  git checkout -b <new-branch-name>

HEAD is now at 0e8645d... Added build script, updated minunit

bash: line 20: cd: /builds/corneyl/cproject: No such file or directory

ERROR: Build failed with: exit code 1

According to http://stackoverflow.com/questions/34335827/gitlab-runner-fails-creating-android-build-using-the-newer-yml-format this is because the gitlab runner is not consistent in using the correct windows or unix directory seperator slashes. (But no issue was made here)