diff --git a/fdtdump.c b/fdtdump.c
index bdc0f94..d424869 100644
--- a/fdtdump.c
+++ b/fdtdump.c
@@ -21,7 +21,7 @@
 #define MAX_VERSION 17U
 
 #define ALIGN(x, a)	(((x) + ((a) - 1)) & ~((a) - 1))
-#define PALIGN(p, a)	((void *)(ALIGN((unsigned long)(p), (a))))
+#define PALIGN(p, a)	((void *)(ALIGN((uintptr_t)(p), (a))))
 #define GET_CELL(p)	(p += 4, *((const fdt32_t *)(p-4)))
 
 static const char *tagname(uint32_t tag)