Rsync hard-links devices with different mtimes despite -t: expected?

[Matt McCutchen]

On Tue, 2007-10-30 at 17:20 -0400, Matt McCutchen wrote:
> I noticed that rsync is happy to hard-link a device node from a
> --link-dest dir even if its mtime differs from that of the source device
> node and --times is given.  Is this behavior expected?  It seems to
> break the rule that a difference in preserved attributes disqualifies a
> hard link.

The same strange behavior happens for regular files if --size-only is
passed.  The underlying issue is that unchanged_attrs compares all
preserved attributes except mtimes.  Why are mtimes omitted?

Matt