--- a/include/image.h
+++ b/include/image.h
@@ -44,6 +44,10 @@
 
 #endif /* USE_HOSTCC */
 
+#ifndef ulong
+#define ulong unsigned long
+#endif
+
 #if defined(CONFIG_FIT)
 #include <hash.h>
 #include <libfdt.h>
