Possible Bug (core dump) in awk 3.0.6

[Dan Bornstein]

Hi. I just found this bug when running awk 3.0.6. I have verified that the
problem does not occur with awk 3.0.4, but these were on two different
systems with different other libraries as well. In particular, I tested awk
3.0.4 on a RedHat 6.2 installation and awk 3.0.6 on a RedHat 7 installation
(both Intel x86). The core dump makes it look to me like it could be a
problem with libc, but I don't really know how to trace it much further
than I've already done.

The shell script attached below reproduces the problem.

Here's the result of running it:

    % awk --version
    GNU Awk 3.0.6
    Copyright (C) 1989, 1991-2000 Free Software Foundation.
    [...]
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
    % ./testfile.sh
    awk: cmd. line:1: fatal error: internal error
    ./testfile.sh: line 3:  8305 Aborted                 (core dumped) awk 'END 
{ for (i in goodies) delete baddies[goodies[i]]; print baddies[i] }' milk
    % gdb awk core
    GNU gdb 5.0
    Copyright 2000 Free Software Foundation, Inc.
    [...]
    This GDB was configured as "i386-redhat-linux"...
    (no debugging symbols found)...
    Core was generated by `awk \
        BEGIN           { goodies[notreallythere] = "notreallythere";    \
     '.
    Program terminated with signal 6, Aborted.
    Reading symbols from /lib/libm.so.6...done.
    Loaded symbols for /lib/libm.so.6
    Reading symbols from /lib/libc.so.6...done.
    Loaded symbols for /lib/libc.so.6
    Reading symbols from /lib/ld-linux.so.2...done.
    Loaded symbols for /lib/ld-linux.so.2
    #0  0x400714e1 in __kill () from /lib/libc.so.6
    (gdb) where
    #0  0x400714e1 in __kill () from /lib/libc.so.6
    #1  0x400712ba in raise (sig=6) at ../sysdeps/posix/raise.c:27
    #2  0x40072a82 in abort () at ../sysdeps/generic/abort.c:88
    #3  <signal handler called>
    #4  0x400c4cda in strcmp () from /lib/libc.so.6
    #5  0x8058114 in error ()
    #6  0x8055cf9 in strcpy () at ../sysdeps/generic/strcpy.c:31
    #7  0x40060b65 in __libc_start_main (main=0x8055750 <strcpy+49028>, argc=3, 
        ubp_av=0xbffff9f4, init=0x80492ec, fini=0x8065b0c <regfree+18588>, 
        rtld_fini=0x4000df24 <_dl_fini>, stack_end=0xbffff9ec)
        at ../sysdeps/generic/libc-start.c:111

I hope you find this useful. Thanks very much for a set of tools I have
rarely ever had a problem with!

-dan

PS: In case you care, I have two screensavers that are part of the
XScreenSaver distribution (NerveRot and Petri), and I have recently joined
the Java-Gnome team.

##########

#!/bin/sh

awk 'END { for (i in goodies) delete baddies[goodies[i]]; print baddies[i] }' 
milk