patch 8.0.1485: weird autocmd may cause arglist to be changed recursively

Problem:    Weird autocmd may cause arglist to be changed recursively.
Solution:   Prevent recursively changing the argument list. (Christian
            Brabandt, closes #2472)
diff --git a/src/globals.h b/src/globals.h
index 737812c..943bb31 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1594,6 +1594,9 @@
 EXTERN char_u e_invalidreg[]    INIT(= N_("E850: Invalid register name"));
 #endif
 EXTERN char_u e_dirnotf[]	INIT(= N_("E919: Directory not found in '%s': \"%s\""));
+#ifdef FEAT_AUTOCMD
+EXTERN char_u e_au_recursive[]	INIT(= N_("E952: Autocommand caused recursive behavior"));
+#endif
 
 #ifdef FEAT_GUI_MAC
 EXTERN short disallow_gui	INIT(= FALSE);