[yocto] perl 5.22 and 32 bit targets

[Gary Thomas]

On 2016-03-23 09:09, Gary Thomas wrote:
> On 2016-03-23 06:36, Khem Raj wrote:
>> On Tue, Mar 22, 2016 at 9:53 PM, Gary Thomas <gary at mlbassoc.com> wrote:
>>> I hope this is the correct place to discuss this problem.  It
>>> is all about a difference in behavior between a program built
>>> using bitbake/OE (only OE-core is needed) vs building the program
>>> on the target hardware itself.
>>>
>>> I've been struggling with this problem since perl was upgraded
>>> to version 5.22.  I'm working on Amanda (Advanced Maryland Archive
>>> tool) which is written primarily in perl and uses swig interfaces
>>> to access native C functions.  This code works great when using
>>> the previous perl (5.20.x) but fails on all 32 bit targets with
>>> perl 5.22
>>>
>>> The interesting thing is that if I build Amanda on my target
>>> directly (using SDK tools), it works perfectly even with perl
>>> 5.22, so it seems that there is some [subtle] difference between
>>> building using bitbake/OE than when built on the self-hosted
>>> target.  I've compared the builds and the only thing I could
>>> find (from the output of configure) is a difference in sizeof(off_t)
>>> Sadly, when I tried to adjust this in the OE build, it didn't
>>> make any difference, but perhaps I didn't make this change
>>> correctly or completely.
>>
>> do you have largefile support turned on ? if you do then it might
>> be detecting it wrongly during configure since we cache it to a
>> non-largefile case
>>
>> so try to add something like
>>
>> EXTRA_OECONF += "${@bb.utils.contains('DISTRO_FEATURES', 'largefile',
>> 'ac_cv_sizeof_off_t=8', '', d)}"
>>
>> while building perl or the affected program and see if that helps
>
> Thanks for the idea, but that didn't help.  I also forced some CFLAGS
> to match, in particular:
>    -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64
> but this didn't make any difference either.
>

On a whim I just tried a little experiment where I took the *.o files
from the perl subdirectory (where all the swig shims live) from a working
(self-hosted) build and moved them to my bitbake/OE build.  I then touched
all the *.o and *.lo files in the perl tree to force a relink. I then ran
   % bitbake amanda -C compile && bitbake core-image-base
to my surprise, amanda works!  So the culprit lies somewhere within the
swig generated glue.  I've tried comparing these files before and I didn't
find anything other than cosmetic differences (mostly comments about the
name of the file processed, etc).  I've added this subtree to "results"
in my github layer in case someone can see what might be relevant.

Any ideas what might be different and make this swig generated glue fail?
Note that the swig interface files are rebuilt as part of the build process
and both bitbake/OE and self-hosted are using the same swig version.

>>>
>>> Anyway, I'm looking for some help to solve this.  I've put
>>> all the relevant pieces and notes about the process at:
>>>    https://github.com/GaryThomas/meta-amanda.git
>


-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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