Silence most of the remaining warnings

Author: brson

src/libcore/stackwalk.rs

@@ -3,8 +3,8 @@
 #[legacy_modes]; // tjc: remove after snapshot
 
 // NB: transitionary, de-mode-ing.
-// XXX: Can't do this because frame_address needs a deprecated mode.
-//#[forbid(deprecated_mode)];
+// XXX: Can't forbid this because frame_address needs a deprecated mode.
+#[allow(deprecated_mode)];
 #[forbid(deprecated_pattern)];
 
 use cast::reinterpret_cast;

src/libstd/net_tcp.rs

@@ -1,5 +1,6 @@
 //! High-level interface to libuv's TCP functionality
-#[warn(deprecated_mode)];
+// XXX Need FFI fixes
+#[allow(deprecated_mode)];
 
 use ip = net_ip;
 use uv::iotask;

src/libstd/serialization.rs

@@ -1,5 +1,7 @@
 //! Support code for serialization.
 
+#[allow(deprecated_mode)];
+
 /*
 Core serialization interfaces.
 */