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[perl #116665] Undef evaluated to array in some conditions

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From:
Victor Efimov
Date:
February 6, 2013 11:52
Subject:
[perl #116665] Undef evaluated to array in some conditions
Message ID:
rt-3.6.HEAD-27190-1360151524-1846.116665-75-0@perl.org
# New Ticket Created by  Victor Efimov 
# Please include the string:  [perl #116665]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=116665 >


This is a bug report for perl from victor@vsespb.ru,
generated with the help of perlbug 1.39 running under perl 5.10.1.


-----------------------------------------------------------------
[Please describe your issue here]


<code>
#!/usr/bin/perl

use strict;
use warnings;

my $errors = undef;

sub ok
{
    my( $test, $name ) = @_;
    print "[[[$test]]] [[[$name]]]\n";
};

ok( ($errors && ($errors->[0] =~ /Journal file not found/i)), "some
text 1 $errors->[0]" );
ok( ($errors && ($errors->[0] =~ /Journal file not found/i)), "some
text 2 $errors->[0]" );
</code>

prints the following:

<code>
Use of uninitialized value in concatenation (.) or string at poc.pl line 14.
[[[ARRAY(0x137cd48)]]] [[[some text 1 ]]]
Use of uninitialized value in pattern match (m//) at poc.pl line 15.
Use of uninitialized value in concatenation (.) or string at poc.pl line 15.
Use of uninitialized value $name in concatenation (.) or string at
poc.pl line 11.
[[[some text 2 ]]] [[[]]]
</code>

and by the way this code (with modified 'some text' strings)
<code>
#!/usr/bin/perl

use strict;
use warnings;

my $errors = undef;

sub ok
{
    my( $test, $name ) = @_;
    print "[[[$test]]] [[[$name]]]\n";
};

ok( ($errors && ($errors->[0] =~ /Journal file not found/i)), "some text 1" );
ok( ($errors && ($errors->[0] =~ /Journal file not found/i)), "some text 2" );
</code>

prints correct result:

<code>
Use of uninitialized value $test in concatenation (.) or string at
poc.pl line 11.
[[[]]] [[[some text 1]]]
Use of uninitialized value $test in concatenation (.) or string at
poc.pl line 11.
[[[]]] [[[some text 2]]]
</code>

perl 5.10.1 under Linux


p.s.
this found when investigating real bug with Test::Deep/Test::More

[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
    category=core
    severity=high
---
Site configuration information for perl 5.10.1:

Configured by Debian Project at Tue Nov 27 00:14:30 UTC 2012.

Summary of my perl5 (revision 5 version 10 subversion 1) configuration:

  Platform:
    osname=linux, osvers=2.6.42-23-generic,
archname=x86_64-linux-gnu-thread-multi
    uname='linux komainu 2.6.42-23-generic #36-ubuntu smp tue apr 10
20:39:51 utc 2012 x86_64 gnulinux '
    config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN
-Dcccdlflags=-fPIC -Darchname=x86_64-linux-gnu -Dprefix=/usr
-Dprivlib=/usr/share/perl/5.10 -Darchlib=/usr/lib/perl/5.10
-Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5
-Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local
-Dsitelib=/usr/local/share/perl/5.10.1
-Dsitearch=/usr/local/lib/perl/5.10.1 -Dman1dir=/usr/share/man/man1
-Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1
-Dsiteman3dir=/usr/local/man/man3 -Dman1ext=1 -Dman3ext=3perl
-Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio
-Uusenm -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib
-Dlibperl=libperl.so.5.10.1 -Dd_dosuid -des'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=define, usemultiplicity=define
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=define, use64bitall=define, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN
-fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2 -g',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-strict-aliasing
-pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.4.3', gccosandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib /lib64 /usr/lib64
    libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
    perllibs=-ldl -lm -lpthread -lc -lcrypt
    libc=/lib/libc-2.11.1.so, so=so, useshrplib=true, libperl=libperl.so.5.10.1
    gnulibc_version='2.11.1'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -g -L/usr/local/lib
-fstack-protector'

Locally applied patches:


---
@INC for perl 5.10.1:
    /etc/perl
    /usr/local/lib/perl/5.10.1
    /usr/local/share/perl/5.10.1
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.10
    /usr/share/perl/5.10
    /usr/local/lib/site_perl
    .

---
Environment for perl 5.10.1:
    HOME=/root
    LANG=ru_RU.utf8
    LANGUAGE=en_US:en
    LC_MESSAGES=en_US.UTF-8
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
    PERL_BADLANG (unset)
    SHELL=/bin/bash


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