How to update a submodule to latest commit when in detached HEAD state?

Question

I am trying to update my submodules so that they use a more recent commit.

When we use submodules, they are supposed to remain in a detached head state. That's fine.

$ cd myproject
$ cd otherlibrary
$ git status .
HEAD detached from 091eccc
nothing to commit, working tree clean

I did some work in otherlibrary and now I'd like to update myproject so that it will use these new commits in otherlibrary . That means, I need to 'update the submodule' somehow.

This doesn't work: (see? it's still has the same commit number)

$ cd myproject
$ cd otherlibrary
$ git submodule update --remote
$ git status .
HEAD detached from 091eccc
nothing to commit, working tree clean

For completeness, I also tried it like this git submodule update --rebase --remote and like this git submodule update --merge --remote and that doesn't make any difference.

I also read these two SO articles that talk about the subject, but my problem isn't solved by this:

• Update a submodule to the latest commit
• Git submodule detached head state

Answer 1

As phd noted in a comment , to use git submodule update , you must be in the superproject .

(All git submodule update --remote does is cd into the submodule, run a git fetch , and then run a git checkout , so if you don't want to pop back up to the superproject for some reason, you can run the git fetch and git checkout yourself. If you do this, you can poke around in the fetch results and carefully choose the specific commit you'd like, rather than just taking the one identified by origin/master or whatever. Of course, if the one you'd like is whichever one is identified by origin/master , the git submodule update --remote is convenient.)