From bbucklan@jpl-devvax.jpl.nasa.gov

This is a bug report for perl from bbucklan@​jpl-devvax.jpl.nasa.gov,
generated with the help of perlbug 1.34 running under perl v5.8.3.

By executing the perl script below with the -w flag option set,
the warning appears and shows there is an null value that is being
attempted to be compared with another value within FileCache.pm
@​ line 140. Further investigation revealed that the array value
$isopen{$file}->[2] within line 140 is null and appears that it
will always be null. The array value $isopen{$file}->[1] looks
like the proper value meant for the comparision "ne" logic. Since
the value $isopen{$file}->[2] appears to always be null, the code
within the if condition will never execute.

Test Script that generates the error​:

#!/dsw/perl-5.8.3/bin/perl -w

use FileCache;

&FileCache​::cacheout("any_file_test");
&FileCache​::cacheout("any_file_test");
&FileCache​::cacheout_close("any_file_test");

Flags​:
  category=library
  severity=low

Site configuration information for perl v5.8.3​:

Configured by pray at Sat Mar 6 11​:14​:20 PST 2004.

Summary of my perl5 (revision 5.0 version 8 subversion 3) configuration​:
  Platform​:
  osname=solaris, osvers=2.9, archname=sun4-solaris
  uname='sunos fir 5.9 generic_112233-08 sun4u sparc sunw,sun-blade-1000 '
  config_args='-Dcc=/tps/bin/gcc -Dprefix=/dsw/perl-5.8.3'
  hint=recommended, useposix=true, d_sigaction=define
  usethreads=undef use5005threads=undef useithreads=undef usemultiplicity=undef
  useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
  use64bitint=undef use64bitall=undef uselongdouble=undef
  usemymalloc=n, bincompat5005=undef
  Compiler​:
  cc='/tps/bin/gcc', ccflags ='-DDEBUGGING -fno-strict-aliasing -I/tps/include -I/tps/include/libxml2 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
  optimize='-g -O',
  cppflags='-DDEBUGGING -fno-strict-aliasing -I/tps/include -I/tps/include/libxml2'
  ccversion='', gccversion='3.3.3', gccosandvers='solaris2.9'
  intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=4321
  d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
  ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
  alignbytes=8, prototype=define
  Linker and Libraries​:
  ld='/tps/bin/gcc', ldflags ='-L/tps/lib -R/tps/lib '
  libpth=/tps/lib /usr/openwin/lib /usr/lib /usr/ccs/lib
  libs=-lsocket -lnsl -lgdbm -ldb -ldl -lm -lc
  perllibs=-lsocket -lnsl -ldl -lm -lc
  libc=/lib/libc.so, so=so, useshrplib=false, libperl=libperl.a
  gnulibc_version=''
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
  cccdlflags='-fPIC', lddlflags='-G -L/tps/lib -R/tps/lib'

Locally applied patches​:
 

@​INC for perl v5.8.3​:
  /dsw/perl-5.8.3/lib/5.8.3/sun4-solaris
  /dsw/perl-5.8.3/lib/5.8.3
  /dsw/perl-5.8.3/lib/site_perl/5.8.3/sun4-solaris
  /dsw/perl-5.8.3/lib/site_perl/5.8.3
  /dsw/perl-5.8.3/lib/site_perl
  .

Environment for perl v5.8.3​:
  HOME=/home/bbucklan
  LANG=en_US.ISO8859-1
  LANGUAGE (unset)
  LC_COLLATE=en_US.ISO8859-1
  LC_CTYPE=en_US.ISO8859-1
  LC_MESSAGES=C
  LC_MONETARY=en_US.ISO8859-1
  LC_NUMERIC=en_US.ISO8859-1
  LC_TIME=en_US.ISO8859-1
  LD_LIBRARY_PATH=/sfoc/lib
  LOGDIR (unset)
  PATH=/harvest/solaris/Harvest/bin​:/usr/afsws/etc​:/usr/afsws/bin​:/sfoc/mcdm/​:/home/danafa/tdds/etc/bin​:/home/danafa/test_adump218​:/tps/java/bin​:/bin​:/usr/sbin​:/tps/bin​:/sfoc/bin​:/tps/SUNWspro/bin​:/usr/ccs/bin​:/usr/afsws/bin​:/usr/afsws/etc​:/usr/dt/bin​:/usr/openwin/bin​:/usr/local/bin​:/usr/local/sbin​:/usr/ucb​:.​:/harvest/sol8/Harvest/bin​:/home/bbucklan/bin​:/home/stagner/RegTest/bin​:/home/stagner/bin​:/home/bbucklan/TOOLS​:/tps/bin​:/usr/local/bin
  PERL_BADLANG (unset)
  SHELL=/bin/tcsh

From @mhx

On 2004-06-15, at 16​:55​:22 -0000, bbucklan@​jpl-devvax.jpl.nasa.gov (via RT) wrote​:

# New Ticket Created by bbucklan@​jpl-devvax.jpl.nasa.gov
# Please include the string​: [perl #30291]
# in the subject line of all future correspondence about this issue.
# <URL​: http​://rt.perl.org​:80/rt3/Ticket/Display.html?id=30291 >

This is a bug report for perl from bbucklan@​jpl-devvax.jpl.nasa.gov,
generated with the help of perlbug 1.34 running under perl v5.8.3.

-----------------------------------------------------------------
By executing the perl script below with the -w flag option set,
the warning appears and shows there is an null value that is being
attempted to be compared with another value within FileCache.pm
@​ line 140. Further investigation revealed that the array value
$isopen{$file}->[2] within line 140 is null and appears that it
will always be null. The array value $isopen{$file}->[1] looks
like the proper value meant for the comparision "ne" logic. Since
the value $isopen{$file}->[2] appears to always be null, the code
within the if condition will never execute.

Test Script that generates the error​:

#!/dsw/perl-5.8.3/bin/perl -w

use FileCache;

&FileCache​::cacheout("any_file_test");
&FileCache​::cacheout("any_file_test");
&FileCache​::cacheout_close("any_file_test");

Thank you for your report.

Your analysis was correct. The bug has been fixed by the following
change which has been commited to the development version of perl​:

Change 22971 by mhx@​mhx-r2d2 on 2004/06/22 21​:00​:10

  Adjust array index in FileCache.pm.
 
  Subject​: [perl #30291] Use of uninitialized value (array index reference) in FileCache.pm module at line 140
  From​: bbucklan@​jpl-devvax.jpl.nasa.gov (via RT) <perlbug-followup@​perl.org>
  Date​: 15 Jun 2004 16​:55​:22 -0000
  Message-ID​: <rt-3.0.9-30291-90552.18.5392299690759@​perl.org>

Affected files ...

... //depot/perl/lib/FileCache.pm#16 edit

Differences ...

==== //depot/perl/lib/FileCache.pm#16 (text) ====

@​@​ -138,7 +138,7 @​@​
  ( $mode !~ /^\s*(?​:&gt;&gt;|\+?&gt;|\+?&lt;|\|\-|)|\-\|\s*$/ );

  # Mode changed?
- if( $isopen{$file} && ($mode||'>') ne $isopen{$file}->[2] ){
+ if( $isopen{$file} && ($mode||'>') ne $isopen{$file}->[1] ){
  &cacheout_close($file, 1);
  }
 

Marcus

--
Fairy Tale, n.​:
  A horror story to prepare children for the newspapers.

The RT System itself - Status changed from 'new' to 'open'

@mhx - Status changed from 'open' to 'resolved'

From @nwc10

On Tue, Jun 22, 2004 at 11​:26​:08PM +0200, Marcus Holland-Moritz wrote​:

On 2004-06-15, at 16​:55​:22 -0000, bbucklan@​jpl-devvax.jpl.nasa.gov (via RT) wrote​:

Your analysis was correct. The bug has been fixed by the following
change which has been commited to the development version of perl​:

And will be in perl 5.8.5

Nicholas Clark