Compilation fails on rust master

[apasel422]

Compilation fails on rustc 1.0.0-nightly (fed12499e 2015-03-03) (built 2015-03-04) due to some types changing from usize to u32:

src/trie/map.rs:36:40: 36:45 error: mismatched types:
 expected `u32`,
    found `usize`
(expected u32,
    found usize) [E0308]
src/trie/map.rs:36 const MAX_DEPTH: usize = usize::BITS / SHIFT;
                                                          ^~~~~
src/trie/map.rs:36:26: 36:45 error: mismatched types:
 expected `usize`,
    found `u32`
(expected usize,
    found u32) [E0308]
src/trie/map.rs:36 const MAX_DEPTH: usize = usize::BITS / SHIFT;
                                            ^~~~~~~~~~~~~~~~~~~
src/trie/map.rs:704:28: 704:48 error: mismatched types:
 expected `u32`,
    found `usize`
(expected u32,
    found usize) [E0308]
src/trie/map.rs:704     let sh = usize::BITS - (SHIFT * (idx + 1));
                                               ^~~~~~~~~~~~~~~~~~~~
src/enum_set.rs:107:9: 107:31 error: mismatched types:
 expected `usize`,
    found `u32`
(expected usize,
    found u32) [E0308]
src/enum_set.rs:107         self.bits.count_ones()
                            ^~~~~~~~~~~~~~~~~~~~~~
src/enum_set.rs:241:10: 241:15 error: mismatched types:
 expected `usize`,
    found `u32`
(expected usize,
    found u32) [E0308]
src/enum_set.rs:241         (exact, Some(exact))
                             ^~~~~
src/enum_set.rs:241:22: 241:27 error: mismatched types:
 expected `usize`,
    found `u32`
(expected usize,
    found u32) [E0308]
src/enum_set.rs:241         (exact, Some(exact))