@@ -671,6 +671,9 @@ public int size() {
         if (useKeys) {
           return count;  // don't worry about NaN values
 
+        } else if (count == 0) {  // skip the NaN check, it'll AIOOBE
+          return 0;
+
         } else {  // first move NaN values to the end of the list
           int right = count - 1;
           while (values[right] != values[right]) {
 
@@ -566,6 +566,10 @@ public void sortReverse() {
     new Sort() {
       @Override
       public int size() {
+        // if empty, don't even mess with the NaN check, it'll AIOOBE
+        if (count == 0) {
+          return 0;
+        }
         // move NaN values to the end of the list and don't sort them
         int right = count - 1;
         while (data[right] != data[right]) {