Setting the DEBUG variable to 2 or more disables artifact uploads

Someone pointed out strange behavior which I cannot find documented

If you add in the .gitlab-ci.yml file a variable named DEBUG it changes the behavior of uploading artifacts:


no changes

DEBUG=1 see [pages (#1483671074) · Jobs · Peter Tillemans / test_debug_flag · GitLab](example build 1 )

adds 2 mysterious lines

Trying to load /builds/pti1/test_debug_flag.tmp/CI_SERVER_TLS_CA_FILE …
26Dialing: tcp

DEBUG=2 or higher

uploading is disabled:
Uploading artifacts for successful job00:00

23Missing /usr/bin/gitlab-runner-helper. Uploading artifacts is disabled.

24Cleaning up file based variables00:01

25Job succeeded

I cannot find a reference in the documentation to this behavior and all similar environment variables are prefixed and not raw as just DEBUG.

I made a small project to illustrate the behavior.

Can someone point me to the relevant documentation?