Segfaults with rcs file found in glide repo

Hello Eric,

Fellow Debian developer Guillem Jover reported the this bug in https://bugs.debian.org/801110:

Package: cvs-fast-export
Version: 1.34-1
Severity: important

Hi!

I was playing with this package to see if it could generate a better conversion than git-cvsimport or cvs2git, and found that it segfaults or SIGILLs (depending on the optimization level) with the attached file which is present in the glide CVS repository.

cvs seems to cope fine with it being there, and none of the other converters have an issue either. In addition IMO an application should never segfault (or SIGILL) when confronted with apparently bogus data. :)

Thanks,
Guillem

I was able to reproduce the segfault with the following commands:

$ cvssync anonymous@glide.cvs.sourceforge.net:/cvsroot/glide glide3x
$ find glide3x | cvs-fast-export >glide3x.fi
cvs-fast-export: warning - no master branch generated
Segmentation fault
$

The supposedly malformed RCS file, glide3x/Attic/Makefile.linux,v, looks like this:

head     ;
access   ;
symbols  ;
locks    ; strict;
comment  @# @;


desc
@@

Many thanks!

Anthony