I've done some more investigation. There are two seperate issues:
1. The main issue wrt this ticket. It hits you will you are editing code.
It can be reproduced (on any platform) with:
P6="perl6"
lib="templib"
test -e $lib && rm -r $lib;
mkdir $lib
sleep="sleep 2";
echo 'class Top1 { }; need Needed;' > $lib/Top1.pm6
echo 'class Needed { };' > $lib/Needed.pm6;
echo 'class Top2 { }; need Needed;' > $lib/Top2.pm6;
while true; do
printf '#' >> $lib/Needed.pm6 # touch isn't enough here
$sleep;
$P6 -I$lib -e 'need Top1; need Top2; say GLOBAL::.keys;'
done
====
which will fail on the second iteration of the loop:
(Top2 Needed Top1)
===SORRY!===
Missing or wrong version of dependency '/root/templib3/Needed.pm6 (Needed)'
(from '/root/templib3/Top2.pm6 (Top2)')
This one is different because the content of the file has to actually
change rather than just the mtime to trigger it.
2. A smaller issue which is what I was investigating in the prior response.
If you load/recompile a compunit in the same second as the source is
modified it will fail. (your processor and disk has to be fast enough to
pull this off which I *think* is why nine couldn't reproduce it rather than
this being a mac specific thing).
This race condition essentially happens in this line in !load-dependencies:
return False if not $srcIO.e or $modified <= $srcIO.modified;
because it's <= it opens the possibility that a precomp is marked as out of
date a second time even after it has just been re-precompiled in the same
process. The consequence seems to be a bad serialisation. (of course I'm
not suggesting it shouldn't be <= but I guess the fact that something has
just been re-precompiled should override this check).
On Sun, May 22, 2016 at 7:12 AM Lloyd Fournier <lloyd.fo...@gmail.com>
wrote:
> nine++ has attempted to fix this issue:
>
>
> https://github.com/rakudo/rakudo/commit/c59e4dc44772cb09edeb8aa7f0ce0385f951cf5d
>
> Though it seems to have made the failure more random.
>
> Try the following:
> while true; do
> test -e lib && rm -r lib; # this is needed to trigger it for some
> reason
> mkdir lib;
> echo 'class One { }; need Two;' > lib/One.pm6
> echo 'class Two { }; need Three;' > lib/Two.pm6
> echo '' > lib/Three.pm6
> perl6 -Ilib -e 'need One;'
> touch lib/Three.pm6
> perl6 -Ilib -e 'need One; say GLOBAL::.keys;'
> done
>
> gives me:
>
> (Two One)
> ()
> (Two One)
> ()
> (Two One)
> ()
> (Two One)
> (Two One)
> (Two One)
> (Two One)
> (Two One)
> ()
>
> I wrote a test and push it to roast.
>
>
> https://github.com/perl6/roast/commit/4e8b2e02e77e607593907380d30898ff5a926bd7
>
> It seems to have the same issue.
>
> On Sat, May 21, 2016 at 1:45 AM Lloyd Fournier <lloyd.fo...@gmail.com>
> wrote:
>
>> It seems to have been introduced by one of nine's commits on the 13th.
>> This or one of the commits just before it I think:
>>
>>
>> https://github.com/rakudo/rakudo/commit/4fb3f94fcd39699f69e9d175315f9f1357e8faf3
>>
>>
>> On Fri, May 20, 2016 at 11:26 PM Lloyd Fournier <lloyd.fo...@gmail.com>
>> wrote:
>>
>>> err leme try that again
>>>
>>> Precomp is broken for dependency chains 3 or longer when one of the
>>> dependencies down the chain is *changed*.
>>>
>>> To expand: Sometimes it gives you a problem where you get "Missing or
>>> wrong version of dependency" and sometimes symbols that should have been
>>> merged from GLOBALish just aren't there which is the case in the example
>>> above.
>>>
>>> On Fri, May 20, 2016 at 11:18 PM Lloyd Fournier <lloyd.fo...@gmail.com>
>>> wrote:
>>>
>>>> I've been getting something similar and I've managed to golf it.
>>>>
>>>> mkdir lib;
>>>> echo 'class One { }; need Two;' > lib/One.pm6
>>>> echo 'class Two { }; need Three;' > lib/Two.pm6
>>>> echo '' > lib/Three.pm6
>>>> perl6 -Ilib -e 'need One; say (GLOBAL::<One>:exists ?? "OK" !! "NOT
>>>> OK")'
>>>> echo "changing file" && touch lib/Two.pm6 # Three.pm6 will also break
>>>> perl6 -Ilib -e 'need One; say (GLOBAL::<One>:exists ?? "OK" !! "NOT
>>>> OK")'
>>>>
>>>> summary: Precomp is broken for dependency chains 3 or longer when one
>>>> of the dependencies down the chain is broken.
>>>>
>>>> Do we have a way of writing tests for precomp?
>>>>
>>>>
>>>>
>>>>
>>>> On Tue, May 17, 2016 at 4:23 AM mt1957 <perl6-bugs-follo...@perl.org>
>>>> wrote:
>>>>
>>>>> # New Ticket Created by mt1957
>>>>> # Please include the string: [perl #128156]
>>>>> # in the subject line of all future correspondence about this issue.
>>>>> # <URL: https://rt.perl.org/Ticket/Display.html?id=128156 >
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>> I get the following error more often than before after some edits in my
>>>>> source files.
>>>>>
>>>>> Missing or wrong version of dependency
>>>>>
>>>>> '/home/marcel/Languages/Perl6/Projects/mongo-perl6-driver/lib/MongoDB/Wire.pm6
>>>>> (MongoDB::Wire)' (from
>>>>>
>>>>> '/home/marcel/Languages/Perl6/Projects/mongo-perl6-driver/lib/MongoDB/Cursor.pm6
>>>>> (MongoDB::Cursor)'
>>>>>
>>>>> A remedy to this is to touch all source files in the library I work on
>>>>> and than retry. I think that this should not happen, at least not that
>>>>> often (I've seen it several times in about a week I think, twice this
>>>>> evening, to give an idea).
>>>>>
>>>>> This is Rakudo version 2016.04-200-gad82657 built on MoarVM version
>>>>> 2016.04-134-g9879233
>>>>> implementing Perl 6.c.
>>>>>
>>>>> Greetings,
>>>>> Marcel
>>>>>
>>>>
