include ctype.h for isdigit
Bug #102951
diff --git a/poppler/Form.cc b/poppler/Form.cc
index 83bceb2..62bba10 100644
--- a/poppler/Form.cc
+++ b/poppler/Form.cc
@@ -18,6 +18,7 @@
// Copyright 2015 André Guerreiro <aguerreiro1985@gmail.com>
// Copyright 2015 André Esser <bepandre@hotmail.com>
// Copyright 2017 Hans-Ulrich Jüttner <huj@froreich-bioscientia.de>
+// Copyright 2017 Bernd Kuhls <berndkuhls@hotmail.com>
//
//========================================================================
@@ -32,6 +33,7 @@
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
+#include <ctype.h>
#include "goo/gmem.h"
#include "goo/GooString.h"
#include "Error.h"
