Fix up

Author: richo

src/libgreen/macros.rs

@@ -47,7 +47,7 @@ macro_rules! rtassert (
 
 macro_rules! rtabort (
     ($($arg:tt)*) => ( {
-        ::macros::abort(format!($($arg)*).as_slice());
+        ::macros::abort(format!($($arg)*).as_str());
     } )
 )
 

src/libgreen/stack.rs

@@ -164,7 +164,7 @@ fn max_cached_stacks() -> uint {
         0 => {}
         n => return n - 1,
     }
-    let amt = getenv("RUST_MAX_CACHED_STACKS").and_then(|s| from_str(s.as_slice()));
+    let amt = getenv("RUST_MAX_CACHED_STACKS").and_then(|s| from_str(s.as_str()));
     // This default corresponds to 20M of cache per scheduler (at the
     // default size).
     let amt = amt.unwrap_or(10);