diff --git a/src/SortAlgo.cpp b/src/SortAlgo.cpp
index 866702acc..5463bb4d6 100644
--- a/src/SortAlgo.cpp
+++ b/src/SortAlgo.cpp
@@ -575,7 +575,7 @@ std::pair<ssize_t,ssize_t> PartitionTernaryLL(SortArray& A, ssize_t lo, ssize_t
     }
     A.unmark_all();
 
-    return std::make_pair(i,j);
+    return std::make_pair((ssize_t)i,j);
 }
 
 void QuickSortTernaryLL(SortArray& A, size_t lo, size_t hi)