[andoriyu]

`#![no_std]` really means that sysroot isn't available for your platform and you gotta roll your own.

Project I'm working on right now is `#[no_std]`, but my own sysroot covers 90% of real `std`. Which is why I even export it as `std`, so I can use pretty much all crates I would usually use. Because if your platform has an allocator, doesn't matter where it came from, then you can add `liballoc`. `libstd` = `libcore` + `liballoc` + locks + allocator + threads + a few other things that usually depend liballoc. Which means that you have nearly entire libstd available to you if your target platform has an allocator.

Most `#[no_std]` crates that depend on allocator clearly state that they depend on `liballoc` and that you gotta provide one. What I'm trying to say `#[no_std]` doesn't mean embed, it just means sysroot isnt' available for target.