title: Trigger a TeamCity build on changes in a git submodule
body: <p>How to setup TeamCity trigger to start build on changes in git submodule?</p>
  
  <p>Currently you have to update a submodule commit pointer to trigger a build in the main repository, so that TC will register a change in the main repository. </p>
  
  <p><em>Update</em></p>
  
  <p>The problem is the submodule should be always tracking a branch master. AFAIK this cannot be achieved through git itself. I just would like for the build to overcome git limitation in that matter.</p>