Bug#720872: perl: Perl 5.18 "randomly" loses active references under "use threads"

[Niels Thykier]

Package: perl
Version: 5.14.2-21
Severity: normal

Hi,

Noticed this under the Lintian test suite:

"""
[...]
t/scripts/changelog-format.t .............................. ok
===(     314;1   0/22  0/?  1/?  0/?  0/?  0/?   5/21  0/? )============Thread 2 terminated abnormally: Can't call method "minimum_explicit_version" on an undefined value at /usr/share/perl5/Test/MinimumVersion.pm line 54.
t/scripts/needs-info-exists.t ............................. ok
[...]
"""

I doubt this is a bug in Test::MinimumVersion because:
 * it happens randomly
 * last time I saw this problem, it happened in a different script

I believe (but this is a guess) this is related to threads because I
have only seen it in scripts using threads so far (and only in
sections where other threads are active).

Based on my observations, I would guess we are looking at a
race-condition in Perl itself somewhere.  That said, I have no idea
where to look for it (or how to verify this assertion).

~Niels