Re: fatal error when diffing changed symlinks

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Junio,

On Tue, 7 Mar 2017, Junio C Hamano wrote:

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> 
> >> > When viewing a working tree file, oid.hash could be 0{40} and
> >> > read_sha1_file() is not the right function to use to obtain the
> >> > contents.
> >> > 
> >> > Both of these two need to pay attention to 0{40}, I think, as the
> >> > user may be running "difftool -R --dir-diff" in which case the
> >> > working tree would appear in the left hand side instead.
> >> 
> >> As a side note, I think even outside of 0{40}, this should be checking
> >> the return value of read_sha1_file(). A corrupted repo should die(), not
> >> segfault.
> >
> > I agree. I am on it.
> 
> Friendly ping, if only to make sure that we can keep a piece of this
> thread in the more "recent" pile.
> 
> If you have other topics you need to perfect, I think it is OK to
> postpone the fix on this topic a bit longer, but I'd hate to ship
> two releases with a known breakage without an attempt to fix it, so
> if you are otherwise occupied, I may encourage others (including me)
> to take a look at this.  The new "difftool" also has a reported
> regression somebody else expressed willingness to work on, which is
> sort of blocked by everybody else not knowing the timeline on this
> one.  cf. <20170303212836.GB13790@arch-attack.localdomain>
> 
> A patch series would be very welcome, but "Please go ahead if
> somebody else has time, and I'll help reviewing" would be also
> good.

Unfortunately, the obvious fix was not enough. My current work in progress
is in the `difftool-null-sha1` branch on https://gihub.com/dscho/git. I
still have a few other things to tend to, but hope to come back to the
difftool before the end of the week.

Ciao,
Johannes