I think I've found a bit of an edge case in `git submodule update --remote` [1] that got easier to reproduce in 2.30+ under certain configurations. `git submodule--helper print-default-remote` defaults to 'origin' when run in a submodule in a detached HEAD state or on a branch with no remote tracking branch [1]. In git < 2.30, the only way for that default to be incorrect required a user to manually change remote names with something like `git -C ./some-sm remote rename origin foo`. `git rev-parse`ing that ref would naturally fail, but at least it's because the user took manual steps to break git's assumptions. Under git 2.30+ with clone.defaultRemoteName set however, submodules are created with that remote name instead of 'origin'. The same behavior occurs, but this time without direct user action - only a simple `git submodule init && git submodule update --remote` is required. I'm terribly sorry about that regression - I've only just started working on a few projects that use submodules heavily and probably could have found this sooner. I'm happy to fix it, but would *super* appreciate a little guidance. It seems the intention is "use the remote that has the url found in the superproject's .submodules entry", that'd require `git submodule--helper print-default-remote` to be called from the superproject from what I can tell. I've experimented with introducing fallbacks to `remote_for_branch` in `remote.c` [2] as an alternative: 1. use remote tracking branch; or 2. if there's only one remote, use that; or 3. if config.defaultRemoteName is set, use that; or 4. fall back to "origin" This seems to work (at the very least, no tests fail?), but leaves `cd ./some-sm; git remote add foo bar; git remote rename origin baz` open to the original behavior. Something tells me y'all will have a very simple solution that I'm missing :) Again, I'm so sorry for introducing a regression here! Sean Barag [1] https://github.com/git/git/blob/225365fb5195e804274ab569ac3cc4919451dc7f/git-submodule.sh#L571-L584 [2] https://github.com/git/git/blob/225365fb5195e804274ab569ac3cc4919451dc7f/remote.c#L477-L487
