Strict mode eval declares its locals in its own environment.

test/mjsunit/strict-mode.js

Index: test/mjsunit/strict-mode.js
diff --git a/test/mjsunit/strict-mode.js b/test/mjsunit/strict-mode.js
index beca582a02ad3637dc356968ea5915fbf512ab9e..2d676b425946e85974d6692dfcc707c1f5579fa4 100644
--- a/test/mjsunit/strict-mode.js
+++ b/test/mjsunit/strict-mode.js
@@ -1179,3 +1179,10 @@ function CheckPillDescriptor(func, name) {
     assertEquals(test(i), true);
   }
 })();
+
+
+(function TestStrictModeEval() {
+  "use strict";
+  eval("var eval_local = 10;");
+  assertThrows(function() { return eval_local; }, ReferenceError);
+})();