mount -a remounts tmpfs entries: bug or feature?

[busybox at eehouse.org]

busybox's implementation of mount differs from the standalone version
in not refusing to mount entries on top of each other.  With tmpfs
entries where it's actually possible to do this, it succeeds.  That
is, if you have a tmpfs entry in /etc/fstab and run 'mount -a' over
and over you get stacking mounts -- but only with busybox's
implementation.  If you try the same trick with the -v option using
standalone mount you get an error:

 ==> sudo mount -a -v
mount: proc already mounted on /proc
mount: UUID=79f04f7c-1d73-45a4-b996-5a1e88c2127e already mounted on /boot
mount: tmpfs already mounted on /var/tmp
nothing was mounted

Is this a bug or intentional?

Thanks,

--Eric
-- 
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* From the desktop of: Eric House, xwords at eehouse.org                        *
*        Crosswords 4.1.4 for PalmOS now ARM-native: xwords.sourceforge.net  *
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