Update tests

src/test/compile-fail/issue-34222.rs

@@ -1,18 +0,0 @@
-// Copyright 2017 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.
-
-#![feature(rustc_attrs)]
-#![allow(warnings)]
-
-#[rustc_error]
-fn main() { //~ ERROR compilation successful
-    // crash
-    let x = 0;
-}

src/test/compile-fail/useless_comment.rs

@@ -11,17 +11,17 @@
 #![deny(unused_doc_comment)]
 
 fn foo() {
-    /// a //~ ERROR unused doc comment
+    /// a //~ ERROR doc comment not used by rustdoc
     let x = 12;
 
-    /// b //~ ERROR unused doc comment
+    /// b //~ doc comment not used by rustdoc
     match x {
-        /// c //~ ERROR unused doc comment
+        /// c //~ ERROR doc comment not used by rustdoc
         1 => {},
         _ => {}
     }
 
-    /// foo //~ ERROR unused doc comment
+    /// foo //~ ERROR doc comment not used by rustdoc
     unsafe {}
 }