Note that it needs to be built with nightly

rust/coffi/README.md

@@ -12,6 +12,9 @@ height.
cargo run <path-to-png>
```
Should build with Rust 1.6.0-nightly, which is necessary because it
uses the `feature(libc)` flag.
If you use emacs, `flycheck-mode` can check the code on the *fly*, which
is awesome!