Fix some warnings

src/libstd/ascii.rs

@@ -577,6 +577,7 @@ mod tests {
     #[test] #[should_fail]
     fn test_ascii_fail_char_slice() { 'λ'.to_ascii(); }
 
+    #[test]
     fn test_opt() {
         assert_eq!(65u8.to_ascii_opt(), Some(Ascii { chr: 65u8 }));
         assert_eq!(255u8.to_ascii_opt(), None);

src/libstd/io/net/udp.rs

@@ -99,9 +99,8 @@ impl Writer for UdpStream {
 #[cfg(test)]
 mod test {
     use super::*;
-    use io::net::ip::{Ipv4Addr, SocketAddr};
+    use io::net::ip::{SocketAddr};
     use io::*;
-    use io::test::*;
     use prelude::*;
 
     iotest!(fn bind_error() {

src/libstd/rt/local.rs

@@ -54,7 +54,6 @@ mod test {
     use unstable::run_in_bare_thread;
     use super::*;
     use rt::task::Task;
-    use rt::local_ptr;
 
     #[test]
     fn thread_local_task_smoke_test() {

src/test/run-pass/reflect-visit-type.rs

@@ -65,7 +65,7 @@ impl TyVisitor for MyVisitor {
     fn visit_estr_uniq(&mut self) -> bool { true }
     fn visit_estr_slice(&mut self) -> bool { true }
     fn visit_estr_fixed(&mut self,
-                        _sz: uint, _sz: uint,
+                        _sz: uint, _sz2: uint,
                         _align: uint) -> bool { true }
 
     fn visit_box(&mut self, _mtbl: uint, _inner: *TyDesc) -> bool { true }