diff --git a/Source/Common/IGListDiff.mm b/Source/Common/IGListDiff.mm
index 6389da34..2ababb61 100644
--- a/Source/Common/IGListDiff.mm
+++ b/Source/Common/IGListDiff.mm
@@ -298,8 +298,8 @@ static id IGListDiffing(BOOL returnIndexPaths,
     }
 
     NSCAssert((oldCount + [mInserts count] - [mDeletes count]) == newCount,
-              @"Sanity check failed applying %li inserts and %lu deletes to old count %lu equaling new count %li",
-              (long)oldCount, (unsigned long)[mInserts count], (unsigned long)[mDeletes count], (long)newCount);
+              @"Sanity check failed applying %lu inserts and %lu deletes to old count %li equaling new count %li",
+              (unsigned long)[mInserts count], (unsigned long)[mDeletes count], (long)oldCount, (long)newCount);
 
     if (returnIndexPaths) {
         return [[IGListIndexPathResult alloc] initWithInserts:mInserts