Re: [RFC PATCH v2 1/4] object: remove "used" field from struct object

Jonathan Tan [off-list ref] writes:

The "used" field in struct object is only used by builtin/fsck. Remove
that field and modify builtin/fsck to use a flag instead.

Signed-off-by: Jonathan Tan <redacted>
---
 builtin/fsck.c | 24 ++++++++++++++----------
 object.c       |  1 -
 object.h       |  2 +-
 3 files changed, 15 insertions(+), 12 deletions(-)

I vaguely recall trying to do this myself a few years ago.  We can
easily spot places within this file that does things like this:

-	obj->flags = HAS_OBJ;

and correctly update it to this:

+	obj->flags &= ~(REACHABLE | SEEN);
+	obj->flags |= HAS_OBJ;

but I didn't do so because I was hesitant having to validate, and
having to maintain the invariant forever, that anything called from
these codepaths is always careful not to clobber the USED bit.

Looks like a reasonable preparatory clean-up that probably should be
doable and should be done way before the main part of the series to
me.  Will queue, together with your other fsck change.

Thanks.