Re: Reproducible, corrupt packfile after fresh git-svn checkout

From: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Date: Aug 8, 2013, 12:38 UTC
Message-ID: <vpqpptofjd3.fsf@anie.imag.fr>
In-Reply-To: <262a9f8309a3812970f47ac9f4e4b49bb972ca49@localhost>

gitml.jexpert@recursor.net writes:

Show 11 quoted lines

>> Regardless of any possible fault in git-svn, there's an obvious bug here
>> with git-fsck.  Can you share the pack (if the project is public) or
>> compile a git-fsck without optimization and with debugging, and run it
>> under valgrind, to hopefully get us a backtrace of where the memory
>> management goes off the rails?
>
> Unfortunately I'm unable to share the pack.
>
> As Java Developer I'm note very savy, but I'd try.
> Do you have me any pointers on ".. without optimization and with
> debugging" and "run it under valgrind"?

To fetch sources and compile:

  git clone https://github.com/git/git.git
  cd git/
  make CFLAGS='-g -O0'

To run gdb:

  gdb --args ./git fsck

Then type "run" at the gdb prompt. When the program crashes, you should get the gdb prompt back. Then, typing "bt" gives you a backtrace, and "bt full" gives you the same with more information (be careful, there may be private information in it).

To use valgrind, just do:

  valgrind ./git fsck

(essentially, it runs the program adding a bunch of runtime checks hence may provide better diagnosis)

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/