diff --git a/lib/buffer.js b/lib/buffer.js
index 8f4e34d289fc27..dc2b656d7a7a33 100644
--- a/lib/buffer.js
+++ b/lib/buffer.js
@@ -247,6 +247,11 @@ Buffer.concat = function(list, length) {
   if (!Array.isArray(list))
     throw new TypeError('list argument must be an Array of Buffers.');
 
+  if (list.length === 0)
+    return new Buffer(0);
+  else if (list.length === 1)
+    return list[0];
+
   if (length === undefined) {
     length = 0;
     for (var i = 0; i < list.length; i++)
@@ -255,11 +260,6 @@ Buffer.concat = function(list, length) {
     length = length >>> 0;
   }
 
-  if (list.length === 0)
-    return new Buffer(0);
-  else if (list.length === 1)
-    return list[0];
-
   var buffer = new Buffer(length);
   var pos = 0;
   for (var i = 0; i < list.length; i++) {