diff --git a/build.py b/build.py
index 239cab71b5..318e65534f 100755
--- a/build.py
+++ b/build.py
@@ -274,6 +274,7 @@ def examples_star_json(name, match):
               "externs/vbarray.js"
             ],
             "define": [
+              "goog.array.ASSUME_NATIVE_FUNCTIONS=true",
               "goog.dom.ASSUME_STANDARDS_MODE=true",
               "goog.json.USE_NATIVE_JSON=true",
               "goog.DEBUG=false"
diff --git a/config/examples-all.json b/config/examples-all.json
index 599762fffd..6dbbc9ec2e 100644
--- a/config/examples-all.json
+++ b/config/examples-all.json
@@ -17,6 +17,7 @@
       "externs/vbarray.js"
     ],
     "define": [
+      "goog.array.ASSUME_NATIVE_FUNCTIONS=true",
       "goog.dom.ASSUME_STANDARDS_MODE=true",
       "goog.json.USE_NATIVE_JSON=true",
       "goog.DEBUG=false"
diff --git a/config/ol.json b/config/ol.json
index bd721f5b31..0740a4c8d5 100644
--- a/config/ol.json
+++ b/config/ol.json
@@ -13,6 +13,7 @@
       "externs/vbarray.js"
     ],
     "define": [
+      "goog.array.ASSUME_NATIVE_FUNCTIONS=true",
       "goog.dom.ASSUME_STANDARDS_MODE=true",
       "goog.json.USE_NATIVE_JSON=true",
       "goog.DEBUG=false"
diff --git a/src/ol/ol.js b/src/ol/ol.js
index 5f2b0bcfa0..614113f890 100644
--- a/src/ol/ol.js
+++ b/src/ol/ol.js
@@ -146,6 +146,8 @@ ol.ENABLE_WEBGL = true;
 
 /**
  * @define {boolean} Support legacy IE (7-8).  Default is `false`.
+ *     If set to `true`, `goog.array.ASSUME_NATIVE_FUNCTIONS` must be set
+ *     to `false` because legacy IE do not support ECMAScript 5 array functions.
  */
 ol.LEGACY_IE_SUPPORT = false;