--- a/src/toplev.h
+++ b/src/toplev.h
@@ -24,10 +24,11 @@
 #if !defined (octave_octave_h)
 #define octave_octave_h 1
 
-#include <stdio.h>
+#include <cstdio>
 
 class tree_statement_list;
 class tree_function;
+class Octave_str_obj;
 
 // Tell g++ that clean_up_and_exit doesn't return;
 
@@ -89,6 +90,9 @@
 // Nonzero means input is coming from startup file.
 extern int input_from_startup_file;
 
+// The command-line options.
+extern Octave_str_obj octave_argv;
+
 #endif
 
 /*