Bug 16184

Summary: AB-INT: bitbake: Can't pickle local object
Product: [Build System, Metadata & Runtime] BitBake Reporter: Mathieu Dubois-Briand <mathieu.dubois-briand>
Component: bitbakeAssignee: Trevor Gamblin <tgamblin>
Status: RESOLVED FIXED QA Contact:
Severity: normal    
Priority: Medium CC: poky.bs.watcher, poky.watcher, randy.macleod, tgamblin
Version: unspecified   
Target Milestone: 6.0   
Hardware: x86   
OS: Multiple   
Whiteboard: AB-INT
OS type for building Yocto: --- Type of Regression: ---
Verified: Documentation change: No (bug/feature does not impact docs)

Description Mathieu Dubois-Briand 2026-02-27 10:46:28 UTC
We saw this error 3 times since yesterday, both on master and on my branch. It looks related to meta-mingw, I now some changes were made recently.


ERROR: An uncaught exception occurred in runqueue
Traceback (most recent call last):
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1663, in execute_runqueue
    return self._execute_runqueue()
           ~~~~~~~~~~~~~~~~~~~~~~^^
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1607, in _execute_runqueue
    retval = self.dump_signatures(dumpsigs)
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1718, in dump_signatures
    p.start()
    ~~~~~~~^^
  File "/usr/lib64/python3.14/multiprocessing/process.py", line 121, in start
    self._popen = self._Popen(self)
                  ~~~~~~~~~~~^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/context.py", line 224, in _Popen
    return _default_context.get_context().Process._Popen(process_obj)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/context.py", line 300, in _Popen
    return Popen(process_obj)
  File "/usr/lib64/python3.14/multiprocessing/popen_forkserver.py", line 35, in __init__
    super().__init__(process_obj)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/popen_fork.py", line 20, in __init__
    self._launch(process_obj)
    ~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/popen_forkserver.py", line 47, in _launch
    reduction.dump(process_obj, buf)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/reduction.py", line 60, in dump
    ForkingPickler(file, protocol).dump(obj)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^
_pickle.PicklingError: Can't pickle local object <function CoreRecipeInfo.init_cacheData.<locals>.<lambda> at 0x7f7925667d70>
when serializing tuple item 0
when serializing collections.defaultdict reconstructor arguments
when serializing collections.defaultdict object
when serializing dict item 'rundeps'
when serializing bb.cache.CacheData state
when serializing bb.cache.CacheData object
when serializing dict item ''
when serializing dict item 'recipecaches'
when serializing bb.cooker.BBCooker state
when serializing bb.cooker.BBCooker object
when serializing dict item 'cooker'
when serializing bb.runqueue.RunQueue state
when serializing bb.runqueue.RunQueue object
when serializing tuple item 0
when serializing method reconstructor arguments
when serializing method object
when serializing dict item '_target'
when serializing multiprocessing.context.Process state
when serializing multiprocessing.context.Process object

ERROR: Running idle function
Traceback (most recent call last):
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/server/process.py", line 418, in idle_thread_internal
    retval = function(self, data, False)
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/cooker.py", line 1554, in buildTargetsIdle
    retval = rq.execute_runqueue()
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1663, in execute_runqueue
    return self._execute_runqueue()
           ~~~~~~~~~~~~~~~~~~~~~~^^
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1607, in _execute_runqueue
    retval = self.dump_signatures(dumpsigs)
  File "/srv/pokybuild/yocto-worker/check-layer/build/layers/bitbake/lib/bb/runqueue.py", line 1718, in dump_signatures
    p.start()
    ~~~~~~~^^
  File "/usr/lib64/python3.14/multiprocessing/process.py", line 121, in start
    self._popen = self._Popen(self)
                  ~~~~~~~~~~~^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/context.py", line 224, in _Popen
    return _default_context.get_context().Process._Popen(process_obj)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/context.py", line 300, in _Popen
    return Popen(process_obj)
  File "/usr/lib64/python3.14/multiprocessing/popen_forkserver.py", line 35, in __init__
    super().__init__(process_obj)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/popen_fork.py", line 20, in __init__
    self._launch(process_obj)
    ~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/popen_forkserver.py", line 47, in _launch
    reduction.dump(process_obj, buf)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.14/multiprocessing/reduction.py", line 60, in dump
    ForkingPickler(file, protocol).dump(obj)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^
_pickle.PicklingError: Can't pickle local object <function CoreRecipeInfo.init_cacheData.<locals>.<lambda> at 0x7f7925667d70>
when serializing tuple item 0
when serializing collections.defaultdict reconstructor arguments
when serializing collections.defaultdict object
when serializing dict item 'rundeps'
when serializing bb.cache.CacheData state
when serializing bb.cache.CacheData object
when serializing dict item ''
when serializing dict item 'recipecaches'
when serializing bb.cooker.BBCooker state
when serializing bb.cooker.BBCooker object
when serializing dict item 'cooker'
when serializing bb.runqueue.RunQueue state
when serializing bb.runqueue.RunQueue object
when serializing tuple item 0
when serializing method reconstructor arguments
when serializing method object
when serializing dict item '_target'
when serializing multiprocessing.context.Process state
when serializing multiprocessing.context.Process object


Summary: There were 2 ERROR messages, returning a non-zero exit code.

INFO: 
INFO: Summary of results:
INFO: 
INFO: meta-mingw ... FAIL (Generating world signatures)
Comment 1 Mathieu Dubois-Briand 2026-02-27 10:52:55 UTC
check-layer fedora43-vk-2 mathieu/master-next&mathieu/master-next-tests completed at 2026-02-27 09:29:35+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/27/builds/3252/steps/16/logs/stdio

check-layer fedora43-vk-2 mathieu/master-next&mathieu/master-next-tests completed at 2026-02-26 18:32:48+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/27/builds/3247/steps/16/logs/stdio

check-layer fedora43-vk-2 master completed at 2026-02-27 01:07:26+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/27/builds/3248/steps/16/logs/stdio
Comment 2 Mathieu Dubois-Briand 2026-02-27 12:03:34 UTC
check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/28/logs/stdio

A lot of things went wrong in this selftest build. Some errors definitely fall
into this ticket, but I fear some are completely unrelated.
oe-selftest-fedora fedora40-vk-4 mathieu/master-next completed at 2026-02-27 11:47:50+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/48/builds/3177/steps/15/logs/stdio
Comment 3 Mathieu Dubois-Briand 2026-03-02 08:35:47 UTC
a-full fedora43-vk-2 mathieu/master-next completed at 2026-02-28 18:35:23+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/29/builds/3311/steps/31/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/12/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/14/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/16/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/18/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/20/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/24/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/26/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/12/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/14/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/16/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/18/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/20/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/24/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/26/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/28/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/30/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/32/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-27 11:55:42+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1012/steps/22/logs/stdio

check-layer-nightly fedora43-vk-2 master completed at 2026-02-28 00:15:14+00:00
https://autobuilder.yoctoproject.org/valkyrie/#/builders/85/builds/1013/steps/22/logs/stdio
Comment 4 Trevor Gamblin 2026-03-03 15:38:23 UTC
I've seen this locally on my F43 workstation too, but I haven't pinpointed it yet. It may be that some of the bitbake implementation around multiprocessing can be updated. I'll try to look soon.
Comment 5 Trevor Gamblin 2026-03-05 15:42:28 UTC
*** Bug 16187 has been marked as a duplicate of this bug. ***
Comment 7 Trevor Gamblin 2026-03-05 16:43:11 UTC
See previous comment, fixed here: https://git.openembedded.org/bitbake/commit/?id=35866d55908009df429870b28cda0d2266074b48