The global-jjb shell script release-job.sh works on git fast-forward merges but fails on other merges.  The critical line that breaks is in the set_variables_common function:

release_files=$(git diff-tree --no-commit-id -r "$GIT_COMMIT" --name-only -- "releases/" ".releases

I think that line just needs to be extended with the "-m" flag per this documentation from git-diff-tree:

       -m
           By default, git diff-tree --stdin does not show differences for merge commits. With
           this flag, it shows differences to that commit from all of its parents. See also -c.

Here's an example of a release job that chokes on a merge of a change that isn't just a fast forward:

https://jenkins.o-ran-sc.org/job/portal-ric-dashboard-release-merge/1/console

Here's an example of a release job that works fine on a merge that is a fast forward:

https://jenkins.o-ran-sc.org/job/nonrtric-release-merge/2/console

Another bad feature - the git parse command needs to detect that a release YAML file was *deleted*. Today it happily fires up and tries to verify the commands in a file that is being deleted, but in my opinion I think it should not.