Issues on pip install --no-binary

While working on installation of Fluidsim on a cluster, I detected a new problem with the pip option --no-binary , which is commonly used to require a new build from source of a package. For example, one can run

pip install mpi4py --no-binary mpi4py

I created a first issue on pip issue tracker ( pypa/pip#12954 ). After some discussion it was understood that it was not a proper bug but actually a breaking change documented in the release notes of pip 23.1 ( https://pip.pypa.io/en/stable/news/#v23-1 ). To achieve the wanted result, one now needs to run commands like:

pip cache remove mpi4py; pip install mpi4py --no-binary mpi4py

I created four distinct and tractable issues about this problem: