diff --git a/src/xfaces.c b/src/xfaces.c
index fb174ab4fac..012cc96470d 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -6418,7 +6418,7 @@ dump_realized_face (struct face *face)
   fprintf (stderr, "underline: %d (%s)\n",
 	   face->underline_p,
 	   SDATA (Fsymbol_name (face->lface[LFACE_UNDERLINE_INDEX])));
-  fprintf (stderr, "hash: " PRIuPTR "\n", face->hash);
+  fprintf (stderr, "hash: %" PRIuPTR "\n", face->hash);
 }