Travis build failed due to git submodule repository not found

Question

I have an Android project with a main app (a git repo) and several modules (git repos cloned as submodule). Today it starts building fail due to submodule repository not found when it tried to build the newly PR code. Travis log looks like below

The main app clones fine, just submodules which failed to clone. I tried to rebuild commits that succeeded last week, but they start building fail too.

Answer 1

After hours of searching and trial, I found it's caused by a recent change of Travis

The solution that works for me is go to each submodule's Travis' settings page and turn on "Allow files from this repository to be used in builds on other repositories".

After turning on all submodules, the building pass like it used to be.