An object to treat as the head of an unreachability trace.
+
If no objects are given, 'git fsck' defaults to using the
-index file, all SHA1 references in `refs` namespace, and all reflogs
+index file, all SHA-1 references in `refs` namespace, and all reflogs
(unless --no-reflogs is given) as heads.
--unreachable::
DISCUSSION
----------
-git-fsck tests SHA1 and general object sanity, and it does full tracking
+git-fsck tests SHA-1 and general object sanity, and it does full tracking
of the resulting reachability and everything else. It prints out any
corruption it finds (missing or bad objects), and if you use the
'--unreachable' flag it will also print out objects that exist but that