1 files changed, 1 insertions, 1 deletions

diff --git a/mps/code/pool.c b/mps/code/pool.c
index 509c5a52552..e2578cf3497 100644
--- a/mps/code/pool.c
+++ b/mps/code/pool.c
@@ -482,7 +482,7 @@ void PoolTraceEnd(Pool pool, Trace trace)
 /* PoolWalk -- walk objects in this segment */
 
 void PoolWalk(Pool pool, Seg seg, FormattedObjectsStepMethod f,
-              void *p, Size s)
+              void *p, size_t s)
 {
   AVERT(Pool, pool);
   AVERT(Seg, seg);