On Thu, 17 Apr 2025 15:39:44 +0800, Ludovic Courtès wrote: > > Hello, > > Hilton Chain <hako@ultrarare.space> writes: > > >> Just realized cross-compilation support (rust-sysroot) is missing when > >> using > >> other build systems. > > > > I think this issue can't be really solved without exposing interface for > > target-inputs in all build systems. > > > > Luckily, all affected packages currently don't support cross-compilation on > > master, so I think this can be left for the future with a bigger change :) > > If cross-compilation of Rust packages doesn’t work at all right now, > it makes sense to leave it for later. > > If it does work, but only for a couple of well-identified packages, > perhaps there are workarounds that could be found for this specific > cases. > > Anyhow, my take as an outsider is that this shouldn’t be a blocker.
Some packages require mixed build systems, e.g. python + cargo, meson + cargo. Previously they were using cargo-build-system and applying build phases from the other build system. With changes currently on rust-team, we can do the reverse and apply build phases from cargo-build-system instead. This can simplify package definitions. cargo-build-system itself supports cross-compilation but requires rust-sysroot as a target input. This is the problem, no interface is available for modifying target-inputs. Currently only a handful of packages have switched build system and on master they don't support cross-compilation either, so the impact is low. But for the long term, this need to be addressed and mixing build systems should be made easier.
