html5ever doesn't compile with never rustc

[o01eg]

   Compiling html5ever_macros v0.0.0 (file:///tmp/html5ever)
macros/src/lib.rs:14:56: 14:60 error: unused or unknown feature, #[deny(unused_features)] on by default
macros/src/lib.rs:14 #![feature(rustc_private, core, collections, std_misc, path)]
                                                                            ^~~~
macros/src/named_entities.rs:63:18: 63:23 error: use of deprecated item: use (start..stop) instead, #[deny(deprecated)] on by default
macros/src/named_entities.rs:63         for n in range(1, k.len()) {
                                                 ^~~~~
error: aborting due to 2 previous errors
Could not compile `html5ever_macros`.

Even if I fix that I get into deprecated old_io errors.

rustc 1.0.0-dev (1760e8749 2015-03-16) (built 2015-03-17)

[Ogeon]

I decided to give it a try and upgrade to the latest nightly, but it fails with two ICEs when running cargo test.

[kmcallister]

I merged some Rust upgrades. I'm waiting on a fix for one of those ICEs, and then we'll see where we are.