The checked out libodb/odb/version-build2.hxx and
libodb-sqlite/odb/sqlite/version-build2.hxx will be overwritten during the
build process but these changes should be ignored. To do this automatically,
run:

git update-index --assume-unchanged libodb/odb/version-build2.hxx
git update-index --assume-unchanged libodb-sqlite/odb/sqlite/version-build2.hxx