auto merge of #7734 : alexcrichton/rust/issue-3395, r=sanxiyn

Also ends up fixing one case in libstd. 

Closes #3395

src/test/compile-fail/lint-ctypes.rs

@@ -8,14 +8,19 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// error-pattern:found rust type
 #[deny(ctypes)];
 
-mod libc {
-    #[nolink]
-    pub extern {
-        pub fn malloc(size: int) -> *u8;
-    }
+use std::libc;
+
+#[nolink]
+extern {
+    pub fn bare_type1(size: int); //~ ERROR: found rust type
+    pub fn bare_type2(size: uint); //~ ERROR: found rust type
+    pub fn ptr_type1(size: *int); //~ ERROR: found rust type
+    pub fn ptr_type2(size: *uint); //~ ERROR: found rust type
+
+    pub fn good1(size: *libc::c_int);
+    pub fn good2(size: *libc::c_uint);
 }
 
 fn main() {

src/test/compile-fail/warn-ctypes.rs

@@ -1,21 +0,0 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// compile-flags:-D ctypes
-// error-pattern:found rust type
-mod libc {
-    #[nolink]
-    extern {
-        pub fn malloc(size: int) -> *u8;
-    }
-}
-
-fn main() {
-}