diff --git a/h_malloc.c b/h_malloc.c
index cc953b9..9d092db 100644
--- a/h_malloc.c
+++ b/h_malloc.c
@@ -27,7 +27,7 @@
 
 #define SLAB_QUARANTINE (SLAB_QUARANTINE_RANDOM_LENGTH > 0 || SLAB_QUARANTINE_QUEUE_LENGTH > 0)
 #define REGION_QUARANTINE (REGION_QUARANTINE_RANDOM_LENGTH > 0 || REGION_QUARANTINE_QUEUE_LENGTH > 0)
-#define MREMAP_MOVE_THRESHOLD (32 * 1024 * 1024)
+#define MREMAP_MOVE_THRESHOLD ((size_t)32 * 1024 * 1024)
 
 static_assert(sizeof(void *) == 8, "64-bit only");