Help debugging "Failed to process pack" when releasing packages

On some occasions I see “Failed to process pack” after releasing a pack, which is sad as I don’t see my pldoc docs online.

This is currently the case for:

I’m not quite sure how to debug this or reproduce the environment the server is running on. I have discovered a few things empirically:

It seems to be sensitive to pldoc syntax errors. These aren’t normally reported in day to day development. I now always run pldoc before release and manually scan for any reported errors. However, there seems to be no such errors in the current release.

I usually include a Makefile in my top level directory. This can sometimes be the source of some errors. It looks like pack_install will make use of a Makefile if it is present to build some standard targets. I usually make dummy targets for install, test, clean, because I am not always sure if my environment will be identical.

I would rather the server just ignore my Makefile and treat my package like one without. I suspect there may be something in my Makefile causing my pack not to be processed, but AFAICT there is no way for me to see the error message or reproduce the environment.