* Step 0: Our target is an ARMv7 device, the triple for this target is `armv7-unknown-linux-gnueabihf`

* Step 1: Install the C cross toolchain
```
$ sudo apt-get install -qq gcc-arm-linux-gnueabihf
```

* Step 2: Install the cross compiled standard crates
```
$ rustup target add armv7-unknown-linux-gnueabihf
```

* Step 3: Configure cargo for cross compilation
```
$ mkdir -p ~/.cargo
$ cat >>~/.cargo/config <<EOF
> [target.armv7-unknown-linux-gnueabihf]
> linker = "arm-linux-gnueabihf-gcc"
> EOF
```

* Test cross compiling a Cargo project
```
$ cargo new --bin hello
$ cd hello
$ cargo build --target=armv7-unknown-linux-gnueabihf
   Compiling hello v0.1.0 (file:///home/ubuntu/hello)
$ file target/armv7-unknown-linux-gnueabihf/debug/hello
```