reachable.hon commit sha1_name.c: teach get_short_sha1() a commit-only option (aa1dec9)
   1#ifndef REACHEABLE_H
   2#define REACHEABLE_H
   3
   4struct progress;
   5extern void mark_reachable_objects(struct rev_info *revs, int mark_reflog, struct progress *);
   6
   7#endif