PSA: You no longer need Xargo to do ARM Cortex-M development

[japaric]

As of the latest nightly (nightly-2018-04-08) rust-std components for the thumbv*m-none-eabi*targets are available. These components contain pre-compiled versions of core, alloc, std_unicode and compiler-builtins.

Install the component with this command:

$ # or any of the other 3 targets (cf. `rustup target list`)
$ rustup target add thumbv7m-none-eabi

Then you’ll be able to build, check, etc. your ARM Cortex-M crates using Cargo:

$ cargo clone cortex-m && cd $_
$ cargo build --target thumbv7m-none-eabi

This change is part of the effort towards making embedded development possible on the stable
channel.

[thejpster]

Yay! If you remember to add the same target that you build with, and bump cortex-m-rt, it works!

[lygstate]

Would arm-none-eabi be added for ARM7 & ARM9?