comments: Convert XXXes to FIXMEs

src/librustc/middle/lang_items.rs

@@ -138,7 +138,7 @@ fn each_item(&self, f: &fn(def_id: def_id, i: uint) -> bool) {
         }
     }
 
-    // XXX: Method macros sure would be nice here.
+    // FIXME #4621: Method macros sure would be nice here.
 
     pub fn const_trait(&const self) -> def_id {
         self.items[ConstTraitLangItem as uint].get()

src/librustc/middle/lint.rs

@@ -720,7 +720,8 @@ fn check_foreign_fn(cx: ty::ctxt, fn_id: ast::node_id,
               ast::foreign_item_fn(decl, _, _) => {
                 check_foreign_fn(cx, it.id, decl);
               }
-              ast::foreign_item_const(*) => {}  // XXX: Not implemented.
+              // FIXME #4622: Not implemented.
+              ast::foreign_item_const(*) => {}
             }
         }
       }