On Tue, 06 Aug 2024 at 10:32:49 +0700, Dima Kogan wrote: > As with most packages, python3-numpy has > > Depends: ${python3:Depends} > > which today expands to > > Depends: python3 (<< 3.13), python3 (>= 3.12~), python3:any > > Can somebody comment about why the :any is on the un-versioned > dependency only? Adding the :any to the other two would fix my problem, > and I'd like to get that added if there isn't a strong reason not to.
I'm guessing you want this because in a cross-compiling scenario, for example build=amd64 and host=riscv64, you want to be able to install python3:amd64 (to be able to run Meson, etc.) together with python3-numpy:riscv64 (so riscv64 code can find numpy.pc)? If python3-numpy contained "pure Python" then python3:any would be enough. python3-six is a good simple example of a package in this situation. But if python3-numpy contains native-code (compiled C/C++/etc.) extensions, then that would be incorrect, because a compiled riscv64 extension cannot be loaded into an amd64 interpreter, and will fail if you try; so it would be wrong to allow python3:amd64 and python3-numpy:riscv64 to be installed together. It appears that python3-numpy *does* contain native code, for example /usr/lib/python3/dist-packages/numpy/core/_simd.cpython-312-x86_64-linux-gnu.so. So the dependency on python3 of the same architecture is correct. This is also why the dependency has to be versioned: the current numpy binaries in unstable would not work correctly with Python 3.11 or 3.13, even if the source does, because the binary package doesn't have *-311-*.so or *-313-*.so (when Python 3.13 becomes a supported version, *-313-*.so will be added by a binNMU). I think you will need to introduce a python-numpy-dev or python3-numpy-dev that is Architecture:any,Multi-Arch:same, or possibly Architecture:all,Multi-Arch:foreign if its contents can easily be made architecture-independent (this only works if the .pc file is the same for every architecture because it only refers to headers in /usr/include and not libraries, in which case it can be moved to /usr/share). You might find that python3-talloc-dev is useful prior art for the Architecture:any,Multi-Arch:same case, and python-dbus-dev is an example of the Architecture:all,Multi-Arch:foreign case. smcv