librustc: Don't allow return_address intrinsic in functions that don't use an out pointer.

src/test/compile-fail/intrinsic-return-address.rs

@@ -0,0 +1,31 @@
+// Copyright 2014 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.
+
+#![allow(warnings)]
+#![feature(intrinsics)]
+
+extern "rust-intrinsic" {
+    fn return_address() -> *const u8;
+}
+
+unsafe fn f() {
+    let _ = return_address();
+    //~^ ERROR invalid use of `return_address` intrinsic: function does not use out pointer
+}
+
+unsafe fn g() -> int {
+    let _ = return_address();
+    //~^ ERROR invalid use of `return_address` intrinsic: function does not use out pointer
+    0
+}
+
+fn main() {}
+
+

src/test/run-pass/intrinsic-return-address.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(intrinsics)];
+#![feature(intrinsics)]
 
 use std::ptr;