diff --git a/stat64.c b/stat64.c
index 3c816cd0..16d33c6d 100644
--- a/stat64.c
+++ b/stat64.c
@@ -29,7 +29,7 @@
 #include "stat.h"
 
 static void
-decode_struct_stat64(struct tcb *tcp, const unsigned long addr)
+decode_struct_stat64(struct tcb *const tcp, const kernel_ureg_t addr)
 {
 	struct strace_stat st;