svn-all-fast-export crash reproducer

[Dave Abrahams]

https://gist.github.com/4552460 shows an svnadmin dump file (just the
first 2 revisions of Boost's SVN repository) and a ruleset that crashes
svn-all-fast-export.

A regular debug build hides the bug, but a release+debuginfo build (per
http://qt-project.org/forums/viewthread/2412) gets me:

#0 SvnRevision::fetchRevProps (this=0xbffff478) at svn.cpp:526
#1 0x08066903 in SvnRevision::commit (this=0xbffff478) at svn.cpp:543
#2 0x080706d8 in SvnPrivate::exportRevision (this=0x809d2a8, revnum=1) at svn.cpp:469
#3 0x080708a9 in Svn::exportRevision (this=0xbffff614, revnum=1) at svn.cpp:144
#4 0x0804d7b3 in main (argc=<error reading variable: Cannot access memory at address 0x1>, argv=<error reading variable: Cannot access memory at address 0x5>) at main.cpp:271

It appears that revision 1 (like revisions 2-5 of Boost's repo) has no
revprops. svnauthor, svndate, and svnlog are all null, and svn2git isn't
prepared to handle that eventuality. I think after this level of
analysis it should be fairly easy to come up with a fix (right?) but I
would feel a lot more confident if someone who had worked with the
svn2git code already produced the fix. Can anyone from KDE-scm-interest
help us? Thanks!

Instructions to reproduce follow:

--8<---------------cut here---------------start------------->8---
mkdir /tmp/crash
cd /tmp/crash
wget https://gist.github.com/raw/4552460/a90c4f9ad1ab58b1b1b5b9bd16687d1ab2ff72cf/crash-svn2git.rules
wget https://gist.github.com/raw/4552460/5e934a4a4f2770a1536e3122d4adc20aebf72679/crash-svn2git.svndump
svnadmin create repo
svnadmin load repo<crash-svn2git.svndump
svn-all-fast-export --rules crash-svn2git.rules repo
--8<---------------cut here---------------end--------------->8---

--
Dave Abrahams
BoostPro Computing Software Development Training
http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost