[qalmakka]

With a GCC-based toolchain, you need to build binutils and GCC for each target you need, plus a sysroot with headers and libraries to target.

With LLVM, the same backend and set of tools can target every single platform LLVM supports, and they also ship their binutils equivalents. Thus, rust in this case could probably be also C or C++; the infrastructure is the same. Rust has also the perk of having a nicer build system and tools that do not require you to lose your sanity in order to cross compile something, which is nice.