BUG: noarch package in multi-output recipe changes CPU architecture mid-build #5349
Description
Checklist
- I added a descriptive title
- I searched open reports and couldn't find a duplicate
What happened?
We recently split up the pyarrow package into more bits and pieces (e.g. distinguish minimal variant for small footprint from full-featured "give me everything"), and now we have a sandwich where the first and last package in a telescopic chain of dependencies are per python, whereas there are two empty metapackages in the middle that could easily be noarch:
pyarrow-core # depends on libarrow*; per python version resp. CUDA/non-CUDA
pyarrow # depends on pyarrow-core; could be noarch
pyarrow-all # depends on pyarrow; could be noarch
pyarrow-tests # depends on pyarrow-all; per python version
I've tried doing that in conda-forge/pyarrow-feedstock#119, and it works fine in native builds, but fails with non-sensical errors on aarch/ppc:
TEST END: /home/conda/feedstock_root/build_artifacts/linux-aarch64/pyarrow-core-16.0.0-py39ha95f412_1_cpu.conda
TEST START: /home/conda/feedstock_root/build_artifacts/noarch/pyarrow-16.0.0-hd8ed1ab_1.conda
WARNING: Multiple meta files found. The meta.yaml file in the base directory (/tmp/tmpnher07k4/info/recipe) will be used.
Reloading output folder (local): ...working... done
Solving environment (_test_env): ...working... failed
WARNING: failed to get package records, retrying. exception was: Unsatisfiable dependencies for platform linux-64: {MatchSpec("16.0.0=*_1_"), MatchSpec("pyarrow==16.0.0=hd8ed1ab_1"), MatchSpec("pyarrow-core=16.0.0[build=*_1_*]")}
Encountered problems while solving:
- nothing provides requested pyarrow-core 16.0.0.* *_1_*
- nothing provides pyarrow-core 16.0.0 *_1_* needed by pyarrow-16.0.0-hd8ed1ab_1
When I say non-sensical, I mean that that the TEST END: at the top just confirmed the local existence of an artefact that should match the requested pattern. Looking closer, what's happening is
TEST END: /home/conda/feedstock_root/build_artifacts/linux-aarch64/pyarrow-core-16.0.0-py39ha95f412_1_cpu.conda
[...] ^^^^^^^^^^^^^
Unsatisfiable dependencies for platform linux-64: ...
~~~~~~~~
i.e. the build switches architecture when getting to the noarch output.
Note that all jobs in that PR want to build:
noarch/pyarrow-16.0.0-hd8ed1ab_1.conda
noarch/pyarrow-all-16.0.0-hd8ed1ab_1.conda
which is the goal - we need to build it in each job in order to successfully build the per-python pyarrow-tests on top, but only one build would be uploaded in the end across all jobs, due to the (intentional!) hash collision.
Conda Info
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Conda Config
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Conda list
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Additional Context
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