Bug #99389 for Moops: Exceptions throws during role composition gobble up all memory then segfault

Wed Oct 08 19:13:53 2014 AMON [...] cpan.org - Ticket created

Subject:

Using nonexistent role gobbles up all memory

If a Moops class uses a role that does not exist, then for some reason the application will run out of memory and crash. Minimal example to reproduce: use Moops; class Foo with DoesNotExist; Tested with Moops 0.033 on perl 5.18.2 and perl 5.20.1

Thu Oct 09 04:49:59 2014 perl [...] toby.ink - Correspondence added

Yowzers! That's a nasty one. This also gobbles up memory: use Moops; class Foo with DoesNotExist { 1 }; So it's not related to empty class definitions. And this fails nicely without gobbling memory: use Moops; class Foo { with qw(DoesNotExist) }; Overall, it seems likely to be caused by applying non-existent roles to the class within a Scope::Guard guard block. Perhaps something odd happens if an exception is thrown in the guard block?

Thu Oct 09 04:49:59 2014 The RT System itself - Status changed from 'new' to 'open'

Thu Oct 09 04:49:59 2014 perl [...] toby.ink - Taken

Fri Oct 10 02:20:03 2014 SAUBER [...] cpan.org - Ticket #99409: Ticket created

Subject:

Missing required method causes segmentation fault

Minimal example for how methods required by role will cause segmentation fault when missing: ~$ cat C.pm use Moops; role R { requires 'm'; } class C with R { } ~$ perl -MC -e0 Segmentation fault (core dumped) ~$ perl -c C.pm Segmentation fault (core dumped) ~$ perl --version This is perl 5, version 18, subversion 2 (v5.18.2) built for x86_64-linux-gnu-thread-multi [...] ~$

Sat Oct 11 15:17:02 2014 perl [...] toby.ink - Ticket #99409: Correspondence added

This seems to be the same thing as RT#99389.

Sat Oct 11 15:17:03 2014 The RT System itself - Ticket #99409: Status changed from 'new' to 'open'

Sat Oct 11 15:17:19 2014 perl [...] toby.ink - Ticket #99409: Merged into ticket #99389

Sat Oct 11 15:17:19 2014 perl [...] toby.ink - Merged into ticket #99389

Sat Oct 11 15:19:24 2014 perl [...] toby.ink - Subject changed from 'Using nonexistent role gobbles up all memory' to 'Exceptions throws during role composition gobble up all memory then segfault'

Sat Oct 11 15:19:35 2014 perl [...] toby.ink - Severity Critical added

Sat Oct 11 16:18:54 2014 perl [...] toby.ink - Correspondence added

Replacing Scope::Guard with Guard.pm fixes things, but I'm not sure I want to rely on Guard.pm which is mlehmannware.

Sat Oct 11 19:10:15 2014 perl [...] toby.ink - Correspondence added

# Viable replacement for Scope::Guard/Guard.pm # from BenGoldberg on IRC... use v5.14; BEGIN { package Magic::Guard; use Variable::Magic qw(wizard cast); use constant CALL_ON_FREE => wizard data => sub { $_[1] }, free => sub { $_[1]() }; sub guard(&) { my $magic; cast $magic, CALL_ON_FREE, $_[0]; \$magic } sub import { no strict 'refs'; *{caller.'::guard'} = \&guard } }; no thanks qw(Magic::Guard); use Magic::Guard; do { my $x = guard { say "in guard"; die "here"; }; say "hello"; };

Sun Oct 12 10:13:55 2014 perl [...] toby.ink - Correspondence added

Resolved in Moops 0.034.

Sun Oct 12 10:13:56 2014 perl [...] toby.ink - Status changed from 'open' to 'resolved'