Re: Error converting from 1.4.4.1 to 1.5.0?

From: Junio C Hamano <junkio@cox.net>
Date: Feb 14, 2007, 17:45 UTC
Message-ID: <7vy7n0pr9x.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <17875.17647.74882.218627@lisa.zopyra.com>

Bill Lear <rael@zopyra.com> writes:

Show 14 quoted lines

> % git fsck-objects --full
> error: Packfile .git/objects/pack/pack-23d1a9af78b4b78d1f3750cf70f83cb91a20ba64.pack SHA1 mismatch with itself
> fatal: failed to find delta-pack base object 90bad0d280a6d7c155bbd9582b35ffcf5e3bdd27
>
>
> % /usr/bin/git --version
> git version 1.4.4.1
>
> % /usr/bin/git fsck-objects --full
> error: Packfile .git/objects/pack/pack-23d1a9af78b4b78d1f3750cf70f83cb91a20ba64.pack SHA1 mismatch with itself
> fatal: failed to find delta-pack base object 90bad0d280a6d7c155bbd9582b35ffcf5e3bdd27
>
> So, all I did was try to do a commit with the new git ... haven't
> recloned, or pulled from upstream...

If you haven't packed the repository lately, the above indicates this is not an issue between 1.4.4.1 and 1.5.0, but you had a corrupt packfile before even started.

How big is this pack, what platform are you working on and whose SHA-1 implementation do you use?

We used to have a bug that fed really large buffer to SHA1_Update() function of the underlying SHA-1 library, which was discovered exactly because somebody reported that "mismatch with itself" message.

Also, do you have a huge blob in the repository? I do not know if it is related but the write_sha1_file_prepare() function on the codepath to write loose objects out would trigger the same bug...