Previously, it would not be possible to call start_command twice for the same struct child_process that has env set. The fix is achieved by moving the loop that modifies the environment block into a helper function. This also allows us to make two other helper functions static. Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>