This implies the `--topo-order` option by default, but the
`--date-order` option may also be specified.
+--show-linear-break[=<barrier>]::
+ When --graph is not used, all history branches are flattened
+ which can make it hard to see that the two consecutive commits
+ do not belong to a linear branch. This option puts a barrier
+ in between them in that case. If `<barrier>` is specified, it
+ is the string that will be shown instead of the default one.
+
ifdef::git-rev-list[]
--count::
Print a number stating how many commits would have been