diff --git a/btree_key.cpp b/btree_key.cpp
index 996ea48..08763e3 100644
--- a/btree_key.cpp
+++ b/btree_key.cpp
@@ -46,7 +46,7 @@
 } // compareKeyDouble
 
 int 
-compareKeyInt32(void * , void * ) {
+compareKeyInt32(void * key1, void * key2) {
   if ((key1 == NULL) || (key2 == NULL)) return 0;
 
   const int32 * int32Key1 = static_cast<const int32 *>(key1);