diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 3c1816e371..931517133b 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -6935,7 +6935,7 @@ current:
 						 * Copy end of page, adjusting alignment so
 						 * compiler may copy words instead of bytes.
 						 */
-						off = (PAGEHDRSZ + data->mv_size) & -sizeof(size_t);
+						off = (PAGEHDRSZ + data->mv_size) & -(int)sizeof(size_t);
 						memcpy((size_t *)((char *)np + off),
 							(size_t *)((char *)omp + off), sz - off);
 						sz = PAGEHDRSZ;