row-changed handler treepath lifespan

[Kevin Ryde <user42 zip com au>]

The program below gets for me

signal handler:
  $VAR1 = bless( do{\(my $o = 137867656)}, 'Gtk2::TreePath' );
  0
mainline:
  $VAR1 = bless( do{\(my $o = 137867656)}, 'Gtk2::TreePath' );
GLib-ERROR **: /tmp/buildd/glib2.0-2.16.4/glib/gmem.c:156: failed to allocate 1657472160 bytes at foo.pl line 
21.
Aborted

Is the treepath allowed to be kept and used later outside the signal
handler?  I know iters have bizarre lifespan rules, but I thought
treepaths were ok (or as ok as anything in the path/iter/model debacle
can be said to be ok! :-).

use strict;
use warnings;
use Gtk2 '-init';
use Data::Dumper;

my $store = Gtk2::ListStore->new ('Glib::String');

my $global_path;
$store->signal_connect (row_changed => sub {
                          my ($concat, $path, $iter) = @_;
                          $global_path = $path;
                          print "signal handler:\n";
                          print "  ",Dumper($global_path);
                          print "  ",$global_path->to_string,"\n";
                        });
$store->append;
$store->set ($store->get_iter_first, 0 => 'one');

print "mainline:\n";
print "  ",Dumper($global_path);
print "  ",$global_path->to_string,"\n";
exit 0;