ssh-push.con commit fast-import: Fail if a non-existant commit is used for merge (2f6dc35)
   1#define COUNTERPART_ENV_NAME "GIT_SSH_PULL"
   2#define COUNTERPART_PROGRAM_NAME "git-ssh-pull"
   3#define MY_PROGRAM_NAME "git-ssh-push"
   4#include "ssh-upload.c"