if done in a routine and returned to MAIN; it dumps core

So the following would dump core: 
my $dsgn = create_new();
$dsgn->(method);

sub create_new {
    my $ret = new (c++_object);
    return $ret;
}

[download]
I wonder what would happen if the reference count were incremented before returning: 
my $dsgn = create_new();
$dsgn->(method);

sub create_new {
    my $ret = new (c++_object);
    refcnt_inc($ret);
    return $ret;
}

[download]
I don't think there exists a perl function/module that implements a reference count increment - in which case you'd need to do it with Inline::C/XS/SWIG. (I guess SWIG can help out there ... I know nothing about it.) Even if incrementing the reference count does work, that doesn't guarantee that it's the most appropriate thing to do.

A simple little Inline::C script that increments the reference count: 
use warnings;
use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

void refcnt_inc(SV * sv) {
     SvREFCNT_inc(sv);
}

SV * get_refcnt(SV * sv) {
    return newSVuv(SvREFCNT(sv));
}

EOC

$x = 1;
print get_refcnt($x), "\n";
refcnt_inc($x);
print get_refcnt($x), "\n";

[download]

Not sure if there's anything in this post that helps .... :-)

Cheers,
Rob

In reply to Re^3: C++ object & PERL garbage collection by syphilis
in thread C++ object & PERL garbage collection by Anonymous Monk

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