re PR ada/71358 (GNAT.Command_Line.Getopt fails if there are no switches)

	PR ada/71358
	* g-comlin.adb (Display_Section_Help): Do not dereference
	Config.Switches if it's null.
	(Getopt): Likewise.

From-SVN: r236975

gcc/ada/ChangeLog

+2016-06-01  Simon Wright  <simon@pushface.org>
+
+	PR ada/71358
+	* g-comlin.adb (Display_Section_Help): Do not dereference
+	Config.Switches if it's null.
+	(Getopt): Likewise.
+
 2016-05-31  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* s-osinte-kfreebsd-gnu.ads (clock_getres): Define.

gcc/ada/g-comlin.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1999-2015, Free Software Foundation, Inc.         --
+--          Copyright (C) 1999-2016, Free Software Foundation, Inc.         --
 --                                                                          --
 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
 -- terms of the  GNU General Public License as published  by the Free Soft- --
@@ -3151,16 +3151,18 @@ package body GNAT.Command_Line is
 
          New_Line;
 
-         if Section /= "" then
+         if Section /= "" and then Config.Switches /= null then
             Put_Line ("Switches after " & Section);
          end if;
 
          --  Compute size of the switches column
 
+         if Config.Switches /= null then
             for S in Config.Switches'Range loop
                Max_Len := Natural'Max
                  (Max_Len, Switch_Name (Config.Switches (S), Section)'Length);
             end loop;
+         end if;
 
          if Config.Aliases /= null then
             for A in Config.Aliases'Range loop
@@ -3173,6 +3175,7 @@ package body GNAT.Command_Line is
 
          --  Display the switches
 
+         if Config.Switches /= null then
             for S in Config.Switches'Range loop
                declare
                   N : constant String :=
@@ -3192,6 +3195,7 @@ package body GNAT.Command_Line is
                   end if;
                end;
             end loop;
+         end if;
 
          --  Display the aliases
 
@@ -3454,6 +3458,7 @@ package body GNAT.Command_Line is
 
       --  Initialize output values for automatically handled switches
 
+      if Config.Switches /= null then
          for S in Config.Switches'Range loop
             case Config.Switches (S).Typ is
                when Switch_Untyped =>
@@ -3473,6 +3478,7 @@ package body GNAT.Command_Line is
                   end if;
             end case;
          end loop;
+      end if;
 
       --  For all sections, and all switches within those sections