Fixed: iOS build was broken because of deprecated APIs

src/libstd/os.rs

@@ -1173,9 +1173,7 @@ fn real_args_as_bytes() -> Vec<Vec<u8>> {
             let utf_c_str: *const libc::c_char =
                 mem::transmute(objc_msgSend(tmp, utf8Sel));
             let s = CString::new(utf_c_str, false);
-            if s.is_not_null() {
-                res.push(s.as_bytes_no_nul().to_vec())
-            }
+            res.push(s.as_bytes_no_nul().to_vec())
         }
     }
 

src/libstd/rt/backtrace.rs

@@ -278,9 +278,10 @@ mod imp {
         let cnt = unsafe { backtrace(buf.as_mut_ptr(), SIZE as libc::c_int) as uint};
 
         // skipping the first one as it is write itself
-        result::fold_(range(1, cnt).map(|i| {
+        let iter = range(1, cnt).map(|i| {
             print(w, i as int, buf[i])
-        }))
+        });
+        result::fold(iter, (), |_, _| ())
     }
 
     #[cfg(not(target_os = "ios", target_arch = "arm"))]