The Python binding rebuilds and reinstalls libceed.so and the headers which is not necessary

[yurivict]

As a binding, it should use the pre-installed libceed.so

Could you please consider fixing the Python build such that it would only build parts necessary for the binding and not the whole thing?

All redundant files:

%%PYTHON_SITELIBDIR%%/libceed/include/ceed.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/backend.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/ceed-f32.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/ceed-f64.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/ceed.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/cuda.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/fortran.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/hip.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-atomic-add-fallback.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-gen-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-jit.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-basis-nontensor-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-basis-nontensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-basis-tensor-at-points.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-basis-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-operator-assemble-diagonal.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-operator-assemble.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-qfunction.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-restriction-at-points.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-restriction-curl-oriented.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-restriction-offset.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-restriction-oriented.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-ref-restriction-strided.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-shared-basis-read-write-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-shared-basis-tensor-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-shared-basis-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/cuda/cuda-types.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-identity.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-mass1dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-mass2dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-mass3dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-massapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson1dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson1dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson2dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson2dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson3dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-poisson3dbuild.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-scale.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-vectormassapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-vectorpoisson1dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-vectorpoisson2dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/gallery/ceed-vectorpoisson3dapply.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-gen-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-jit.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-basis-nontensor-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-basis-nontensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-basis-tensor-at-points.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-basis-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-operator-assemble-diagonal.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-operator-assemble.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-qfunction.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-restriction-at-points.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-restriction-curl-oriented.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-restriction-offset.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-restriction-oriented.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-ref-restriction-strided.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-shared-basis-read-write-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-shared-basis-tensor-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-shared-basis-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/hip/hip-types.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-grad-1d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-grad-2d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-grad-3d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-interp-1d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-interp-2d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-interp-3d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-interp-deriv-nontensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-weight-1d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-weight-2d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-weight-3d.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-basis-weight-nontensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-common-defs.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-common-nontensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/magma/magma-common-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-gen-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-jit.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-ref-qfunction.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-shared-basis-read-write-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-shared-basis-tensor-templates.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-shared-basis-tensor.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/jit-source/sycl/sycl-types.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceed/types.h
%%PYTHON_SITELIBDIR%%/libceed/include/ceedf.h
%%PYTHON_SITELIBDIR%%/libceed/lib/libceed.so
%%PYTHON_SITELIBDIR%%/libceed/lib/pkgconfig/ceed.pc

[jeremylt]

The python bindings need a lot of those headers for GPU functionality. The majority of those files you listed are actually needed.

[jedbrown]

Also, we wanted pip install libceed to work. If the user needed to install libceed.so (and presumably the headers) manually, it would be a terrible workflow for Python users. As a packager, you can choose to split these, but the current organization is/was our best effort to follow Python packaging guidelines.

[yurivict]

@jeremylt

They are absolutely needed, no doubt.
But you missed my point.
They are already provided by the libceed C library package.
There is no need to rebuild and reinstall them as a part of the Python binding.

[yurivict]

Also, we wanted pip install libceed to work.

You should have a build-time option to build and include libceed or not.
All clean distros wouldn't want libceed to be rebuilt. Only Python's wheel needs this to be included.

[jedbrown]

Can you point us at a Python best practices example with a C library (that is bundled for wheels) that works the way you envision?

[yurivict]

Can you point us at a Python best practices example with a C library (that is bundled for wheels) that works the way you envision?

Yes: The Facebook's faiss project (https://github.com/facebookresearch/faiss) does it the right way.
They first build the C/C++ library which is ported and packaged as such.
Then they have a Python binding project as a completely separate sub-project faiss/python that builds using the separate C/C++ package.

And they do have the pip wheel packages on PYPI which means that they also package them correctly for pip with the shared library included.

Their structure is the same as in libCEED, except that they use cmake instead of GNU make.

IMO faiss does this as it should be.