diff --git a/lib/smalloc.js b/lib/smalloc.js
index 22525ad0dec..ba042c6c4c5 100644
--- a/lib/smalloc.js
+++ b/lib/smalloc.js
@@ -37,6 +37,7 @@ Object.defineProperty(exports, 'kMaxLength', {
 // enumerated values for different external array types
 var Types = {};
 
+// Must match enum v8::ExternalArrayType.
 Object.defineProperties(Types, {
   'Int8': { enumerable: true, value: 1, writable: false },
   'Uint8': { enumerable: true, value: 2, writable: false },
@@ -68,7 +69,7 @@ function alloc(n, obj, type) {
     throw new TypeError('obj must be an Object');
   }
 
-  // 1 == v8::kExternalByteArray, 9 == v8::kExternalPixelArray
+  // 1 == v8::kExternalUint8Array, 9 == v8::kExternalUint8ClampedArray
   if (type < 1 || type > 9)
     throw new TypeError('unknown external array type: ' + type);
   if (util.isArray(obj))
diff --git a/src/smalloc.cc b/src/smalloc.cc
index f2eedc369f3..d271479e41b 100644
--- a/src/smalloc.cc
+++ b/src/smalloc.cc
@@ -147,23 +147,23 @@ void CallbackInfo::WeakCallback(Isolate* isolate, Local<Object> object) {
 // return size of external array type, or 0 if unrecognized
 size_t ExternalArraySize(enum ExternalArrayType type) {
   switch (type) {
-    case v8::kExternalUnsignedByteArray:
+    case v8::kExternalUint8Array:
       return sizeof(uint8_t);
-    case v8::kExternalByteArray:
+    case v8::kExternalInt8Array:
       return sizeof(int8_t);
-    case v8::kExternalShortArray:
+    case v8::kExternalInt16Array:
       return sizeof(int16_t);
-    case v8::kExternalUnsignedShortArray:
+    case v8::kExternalUint16Array:
       return sizeof(uint16_t);
-    case v8::kExternalIntArray:
+    case v8::kExternalInt32Array:
       return sizeof(int32_t);
-    case v8::kExternalUnsignedIntArray:
+    case v8::kExternalUint32Array:
       return sizeof(uint32_t);
-    case v8::kExternalFloatArray:
+    case v8::kExternalFloat32Array:
       return sizeof(float);   // NOLINT(runtime/sizeof)
-    case v8::kExternalDoubleArray:
+    case v8::kExternalFloat64Array:
       return sizeof(double);  // NOLINT(runtime/sizeof)
-    case v8::kExternalPixelArray:
+    case v8::kExternalUint8ClampedArray:
       return sizeof(uint8_t);
   }
   return 0;