diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 812e59e13fe61daaafff5a97aaea583b09f44c92..a53ee1f6fc24310eff12c1b9e5181567b3a0615f 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1709,7 +1709,8 @@ static int __init initialize_ptr_random(void)
 early_initcall(initialize_ptr_random);
 
 /* Maps a pointer to a 32 bit unique identifier. */
-static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
+static char *ptr_to_id(char *buf, char *end, const void *ptr,
+		       struct printf_spec spec)
 {
 	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
 	unsigned long hashval;