cross

g apart. I can cross compile for iOS/tvOS/etc on my Mac; that’s about it. Zig manages to solve this for all its targets by pre-processing simplifications of the various libcs, which are then bundled into the Zig binary (as 3 very small files). It generates a useless but linkable .so file from the preprocessed files for any target on the fly. It gets you the correct libc headers. Then it uses LLD instead of making you hunt around on Ubuntu forum posts finding and downloading the correct GNU linker for your specific architecture. So you don’t link to a real libc, but you don’t have to compile one either. (Until you want to execute a binary with QEMU, but usually non-simulated target machines have a libc.so already.) (Aside: Golang solves this by not depending on libc at all, by reimplementing most of it including the syscalls in Go, and I believe by using its own multi-target linker. Many pros and many cons, but an approach Google is happy to sponsor.) If you’re saying this approach would be infeasible for Rust std/core, then yes obviously. It’s statically linked, you can’t get away with a fake .so file. But that was never really the issue. Rustc can build std’s rlib files for any target effortlessly. And yet cross compiling is still a pretty poor experience. The state of the art for Rust developers at the moment is rust-embedded/cross, which solves the same libc+linker problem that Zig does, naively, by literally using Docker and per-target Ubuntu images to download prebuilt GCC and libc packages from Apt. Basically we can do way better than that, because Zig showed us how. See this Dockerfile for what I mean: https://github.com/rust-embedded/cross/blob/master/docker/Do...