Re: Serious bug with pretty format strings & empty bodies?

From: Junio C Hamano <gitster@pobox.com>
Date: Dec 22, 2007, 08:39 UTC
Message-ID: <7vhcibyvh0.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <57518fd10712210247s2fcbbf61ke67bbdc0f5ffe70b@mail.gmail.com>

"Jonathan del Strother" <maillist@steelskies.com> writes:

> Has anyone actually managed to reproduce my problem?  I've got
> multiple repos here that show the problem in several commits, made by
> different people.  However, I can't actually come up with a way to
> reproduce it at will...

Marking an issue as a "serious bug" without giving enough material for reproduction nor diagnosis tends to discourage people from looking into it seriously, as the issue cannot be even judged if it is really serious. For example:

  On Dec 19, 2007 6:44 PM, Alex Riesen <raa.lkml@gmail.com> wrote:
  > Could you try
  >
  >     git cat-file 18d2480ab689b483ef1ebbdb3f7420904049ba0b
  >
  > (or any other problematic commit) and post its output here?

  You mean git cat-file commit ... ?
  I get the normal output, but the problematic commits don't show a
  newline character at the end of the cat-file output.

"I get the normal output" is not what Alex asked you to supply, nor would be sufficient information. There may be some abnormality in the commit object that you probably did not spot, but Alex or other people may have been able to if you were actually posted its output here.

I have been suspecting that there is a NUL in the middle of the message somehow (I know the lowest-level plumbing commit-tree allows any byte sequence in the log message if you worked hard enough), which the parser is not prepared to cope with, but we haven't seen enough evidence to support nor refute that theory. We do not have much to work from.

One thing I noticed funny in your original message was "-1-". Is it essential that the number is spelled incorrectly to reproduce this problem?

  $ git rev-list -1- --pretty=format:"%s%n%b"
  18d2480ab689b483ef1ebbdb3f7420904049ba0b
  commit 18d2480ab689b483ef1ebbdb3f7420904049ba0b
  Try to flush log files before terminating the app
  tree 57bc7cf30a10aee96251852125cf30fd2c81d7aa
  parent 04c833865828538315fcdf6e187da077869ce444
  author Jonathan del Strother <jon.delStrother@bestbefore.tv> 1197901755 +0000
  committer Jonathan del Strother <jon.delStrother@bestbefore.tv> 1197901755 +0000

  Check that ThreadWorker's work method actually returns a value with
  method signatures