Hi Monks

I'm having a problem with a large object-based system which results in perl SEGVing. I've reduced it to a small case, which involves calling the contructor of a singleton-type object during global destruction.

I'm aware that it's not a particularly nice thing to do, but I don't think crashing is an appropriate response from perl!

*Edited to remove weaken(), as it is not related to the issue*

The following file is Foo.pm:

package Foo;
use strict;
use XML::LibXML;
use Scalar::Util qw/weaken/;

sub DESTROY {
        my $self=shift;
        warn "\n\n$self dtor";
}

sub new() {
        warn "\n\n".__PACKAGE__." xtor";
        my $self     = {};
        bless $self, __PACKAGE__;
        my $parser = new XML::LibXML();
        my $confdoc = $parser->parse_string('<foo att1="val1"/>');
        my $root = $confdoc->documentElement();
        my @nodes = $root->findnodes('/*');
        for my $n (@nodes){
                for my $att ($n->attributes()) {
                        my $foo = $att->nodeName;
                        warn "foo $foo";
                        warn "lctest: ".lc("LOWERCASEME!");
                        warn "lcfoo ".lc($foo);
                        my ($key, $val) = (lc($att->nodeName), lc($att
+->getValue));
                        warn "$key - $val";
                }
        }
        warn "\n".__PACKAGE__."xtor COMPLETE";
        return $self;
}
1;

[download]

If I then instantiate the object from a destructor it crashes, but only if I created one earlier!?

geedorah:~/perldtorbug# perl -MFoo -e 'package foo; bless ($self=[]) =
+> __PACKAGE__; sub DESTROY {Foo->new()}'


Foo xtor at Foo.pm line 12 during global destruction.
foo att1 at Foo.pm line 22 during global destruction.
lctest: lowercaseme! at Foo.pm line 23 during global destruction.
lcfoo att1 at Foo.pm line 24 during global destruction.
att1 - val1 at Foo.pm line 26 during global destruction.

Fooxtor COMPLETE at Foo.pm line 29 during global destruction.


Foo=HASH(0x81cea10) dtor at Foo.pm line 8 during global destruction.
geedorah:~/perldtorbug# perl -MFoo -e 'package foo; bless ($self=[]) =
+> __PACKAGE__;$f=Foo->new(); sub DESTROY {Foo->new()}'


Foo xtor at Foo.pm line 12.
foo att1 at Foo.pm line 22.
lctest: lowercaseme! at Foo.pm line 23.
lcfoo att1 at Foo.pm line 24.
att1 - val1 at Foo.pm line 26.

Fooxtor COMPLETE at Foo.pm line 29.


Foo=HASH(0x817fa00) dtor at Foo.pm line 8 during global destruction.


Foo xtor at Foo.pm line 12 during global destruction.
foo att1 at Foo.pm line 22 during global destruction.
lctest: lowercaseme! at Foo.pm line 23 during global destruction.
Segmentation fault
geedorah:~/perldtorbug# dmesg |tail -1
[1797167.620092] perl[9540]: segfault at 0 ip 081178d3 sp bfffdd90 err
+or 4 in perl[8048000+131000]
geedorah:~/perldtorbug# perl -v

This is perl, v5.10.0 built for i486-linux-gnu-thread-multi

Copyright 1987-2007, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using "man perl" or "perldoc perl".  If you have access to
+ the
Internet, point your browser at http://www.perl.org/, the Perl Home Pa
+ge.

geedorah:~/perldtorbug#

[download]

Should I perlbug it?

thanks


peter

In reply to perl crash during global destruction by flipper

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