Build Failure: RuntimeError: context has already been set in multiprocessing on Python 3.14
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Description
Plaintext
File "/home/darky/.cache/yay/openage-git/src/build/openage/main.py", line 178, in
multiprocessing.set_start_method('spawn')
File "/usr/lib/python3.14/multiprocessing/context.py", line 247, in set_start_method
raise RuntimeError('context has already been set')
RuntimeError: context has already been set
System Info
OS: Cachy OS
Python Version: 3.14.3
Compiler: GCC 15.2.1
Openage Version: 0.6.0.r197.g865bd548d-1
Technical Summary for Devs
It appears that in Python 3.14, the multiprocessing context is being initialized earlier than in previous versions. When openage/main.py calls set_start_method('spawn'), it triggers a RuntimeError because the method is not being called with force=True. This prevents the codegen_run from completing, which causes the CMake configuration to fail.
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Research direction
Start in openage/main.py around line 178 and reproduce the Python 3.14 build failure during CMake configuration. Trace the codegen_run path and verify that multiprocessing context setup no longer raises RuntimeError and that CMake configuration completes on Python 3.14.
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Assessment
- Tech stack
- python
- Domain
- build-system
- Issue type
- Bug
- Difficulty
- 2/5
- Estimated time
- 1-3 hours
- Activity status
- Stale
- Clarity
- Clearly specified
- Newbie friendliness
- 55/100