diff --git a/kexdh.c b/kexdh.c
index 4b811b617..98597eade 100644
--- a/kexdh.c
+++ b/kexdh.c
@@ -37,6 +37,7 @@
 #include "kex.h"
 #include "sshbuf.h"
 #include "digest.h"
+#include "ssherr.h"
 #include "dh.h"
 
 int