Index: openssh-7.4p1/configure.ac
===================================================================
--- openssh-7.4p1.orig/configure.ac
+++ openssh-7.4p1/configure.ac
@@ -902,7 +902,6 @@ mips-sony-bsd|mips-sony-newsos4)
 	if test "x$withval" != "xno" ; then
 		need_dash_r=1
 	fi
-	AC_DEFINE([PAM_SUN_CODEBASE])
 	AC_DEFINE([LOGIN_NEEDS_UTMPX])
 	AC_DEFINE([PAM_TTY_KLUDGE])
 	AC_DEFINE([SSHPAM_CHAUTHTOK_NEEDS_RUID], [1],
@@ -916,6 +915,7 @@ mips-sony-bsd|mips-sony-newsos4)
 	AC_DEFINE([PASSWD_NEEDS_USERNAME], [1], [must supply username to passwd
 		in case the name is longer than 8 chars])
 	AC_DEFINE([BROKEN_TCGETATTR_ICANON], [1], [tcgetattr with ICANON may hang])
+	AC_DEFINE([PTY_ZEROREAD], [1], [read(2) can return 0 for a non-closed pty fd])
 	external_path_file=/etc/default/login
 	# hardwire lastlog location (can't detect it on some versions)
 	conf_lastlog_location="/var/adm/lastlog"
Index: openssh-7.4p1/kex.h
===================================================================
--- openssh-7.4p1.orig/kex.h
+++ openssh-7.4p1/kex.h
@@ -26,6 +26,8 @@
 #ifndef KEX_H
 #define KEX_H
 
+#include <signal.h>
+
 #include "mac.h"
 #include "buffer.h" /* XXX for typedef */
 #include "key.h" /* XXX for typedef */
Index: openssh-7.4p1/openbsd-compat/regress/closefromtest.c
===================================================================
--- openssh-7.4p1.orig/openbsd-compat/regress/closefromtest.c
+++ openssh-7.4p1/openbsd-compat/regress/closefromtest.c
@@ -24,8 +24,6 @@
 
 #define NUM_OPENS 10
 
-int closefrom(int);
-
 void
 fail(char *msg)
 {