diff --git a/lib/libc/net/base64.c b/lib/libc/net/base64.c
index 6737c187032..8a9c59e3142 100644
--- a/lib/libc/net/base64.c
+++ b/lib/libc/net/base64.c
@@ -193,10 +193,7 @@ b64_ntop(u_char const *src, size_t srclength, char *target, size_t targsize) {
  */
 
 int
-b64_pton(src, target, targsize)
-	char const *src;
-	u_char *target;
-	size_t targsize;
+b64_pton(const char *src, u_char *target, size_t targsize)
 {
 	int tarindex, state, ch;
 	u_char nextbyte;