I have a server written in Perl that does some tasks that clients ask it to. Requests and responses are passed using soap, namely SOAP::Lite. Responses can be successful or unsuccessful. The latter are of two types: error codes plus honest-to-God exceptions (well, as close as Perl comes to them, anyway) of type Error or Exception::Class. The problem occurs when SOAP::Serializer tries to serialize objects of type Error. Error.pm has the following code (shortened for our purposes):

use overload ("0+" => 'value');
sub value {
    my $self = shift;
    exists $self->{'-value'} ? $self->{'-value'} : undef;
}
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Note that this subroutine may return undef. Now, SOAP::Serializer calls subroutine gen_id on references, which for normal objects is just the value of memory address:

sub gen_id { sprintf "%U", $_[1] }
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Now, the problem is that when objects of type Error do not have a value (returns undef), this produces a segfault in perl 5.6.1. This problem can be demonstrated with the following short script:

package My;

use overload ('0+' => 'num_conv');
sub new {
    my $self = shift;
    bless {}, ref($self) || $self;
}
sub num_conv { undef }

package main;
my $var = My->new;
print int($var);
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We see that when numeric conversion overloading function returns undef to built-in Perl functions that invoke it, that crashes perl. My question is, how do I approach this problem? Do I try to

• find out whether I can modify Error.pm (drop numeric conversion overload insanity) and figuring out the implications of such change;
• modify gen_id routine to turn off numeric conversion overloading for referenced packages that are passed to it;
• other?

Your input is greatly appreciated. Thank you.

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