--- mozilla-release/python/mozbuild/mozbuild/backend/recursivemake.py 2013-12-05 08:07:53.000000000 -0800 +++ mozilla-release_1/python/mozbuild/mozbuild/backend/recursivemake.py 2013-12-12 23:38:39.697318563 -0800 @@ -421,7 +421,7 @@ def _handle_idl_manager(self, manager): build_files = self._purge_manifests['xpidl'] - for p in ('Makefile', 'backend.mk', '.deps/.mkdir.done', + for p in ('Makefile.in', 'Makefile', 'backend.mk', '.deps/.mkdir.done', 'xpt/.mkdir.done'): build_files.add(p)