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

[Niels Thykier]

On 2013-08-29 19:41, Dominic Hargreaves wrote:
> On Sun, Aug 25, 2013 at 10:13:39PM +0200, Niels Thykier wrote:
>> 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).
> 
> Does #718438 look like the same issue? Can you reproduce it using
> 5.18 on current sid?
> 
> Cheers,
> Dominic.

I doubt it is the same issue; I never experienced it with perl5.14.
That said, I will try when the perl transition has progressed a bit further.

~Niels