--- a/arc4random.c
+++ b/arc4random.c
@@ -1,5 +1,6 @@
 #include <sys/types.h>
 #include <stdlib.h>
+#include <time.h>
 
 #include "config.h"
 
--- a/interface.c
+++ b/interface.c
@@ -56,6 +56,13 @@
 
 #include "interface.h"
 
+#ifndef HAVE_STRLCPY
+    size_t strlcpy(char *, const char *, size_t);
+#endif
+#ifndef HAVE_STRLCAT
+    size_t strlcat(char *, const char *, size_t);
+#endif
+
 /* Prototypes */
 static int pcap_dloff(pcap_t *);
 
--- a/md5.c
+++ b/md5.c
@@ -23,6 +23,7 @@
    copyright in any changes I have made; this code remains in the
    public domain.  */
 
+#include <string.h>
 #include <sys/types.h>
 
 #ifdef HAVE_CONFIG_H
--- a/scanssh.c
+++ b/scanssh.c
@@ -78,6 +78,10 @@
 #define DNFPRINTF(y, x)
 #endif
 
+#ifndef HAVE_STRLCPY
+    size_t strlcpy(char *, const char *, size_t);
+#endif
+
 struct address_node {
 	TAILQ_ENTRY (address_node) an_next;
 
--- a/xmalloc.c
+++ b/xmalloc.c
@@ -20,6 +20,10 @@
 
 #include "config.h"
 
+#ifndef HAVE_STRLCPY
+    size_t strlcpy(char *, const char *, size_t);
+#endif
+
 void *
 xmalloc(size_t size)
 {