Strict mode eval declares its locals in its own environment.

test/mjsunit/strict-mode.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1161 matching lines @@
     } catch(e) {
       return e instanceof TypeError;
     }
     return false;
   }
 
   for (var i = 0; i < 10; i ++) {
     assertEquals(test(i), true);
   }
 })();
+
+
+(function TestStrictModeEval() {
+  "use strict";
+  eval("var eval_local = 10;");
+  assertThrows(function() { return eval_local; }, ReferenceError);
+})();