Found a few 404s that seemed like simple fixes:
The Result docs use old_io Writer as an example. Fix the link to old_io Writer. There's probably an effort to update the example away from a deprecated api but this was a simple fix.
rustc/plugin was pointing at the old guide and it was a broken link anyways (plugin vs plugins). Point at the book instead.
The main page of the API docs referenced c_{str,vec}. Looks like these were deleted in 25d5a3a19423fee01787de87a56d185dd4e0a4e7. Point at ffi docs instead.
#[plugin] #[no_link] extern crate bleh;
becomes a crate attribute
#![plugin(bleh)]
The feature gate is still required.
It's almost never correct to link a plugin into the resulting library /
executable, because it will bring all of libsyntax and librustc with it.
However if you really want this behavior, you can get it with a separate
`extern crate` item in addition to the `plugin` attribute.
Fixes#21043.
Fixes#20769.
[breaking-change]