switch-c.adb, [...]: Reserve -gnateg for generation of C headers.

2015-11-12  Arnaud Charlet  <charlet@adacore.com>

	* switch-c.adb, gnat1drv.adb, opt.ads: Reserve -gnateg for generation
	of C headers.

From-SVN: r230248

gcc/ada/ChangeLog

 2015-11-12  Arnaud Charlet  <charlet@adacore.com>
 
+	* switch-c.adb, gnat1drv.adb, opt.ads: Reserve -gnateg for generation
+	of C headers.
+
+2015-11-12  Arnaud Charlet  <charlet@adacore.com>
+
 	* back_end.adb, opt.ads (Debugger_Level): Update comment.
 	(Scan_Back_End_Switches): Set Debugger_Level.
 

gcc/ada/gnat1drv.adb

@@ -142,10 +142,15 @@ procedure Gnat1drv is
          Modify_Tree_For_C := True;
       end if;
 
-      --  Set all flags required when generating C code (-gnatd.V)
+      --  -gnatd.V enables C generation
 
       if Debug_Flag_Dot_VV then
          Generate_C_Code := True;
+      end if;
+
+      --  Set all flags required when generating C code
+
+      if Generate_C_Code then
          Modify_Tree_For_C := True;
          Unnest_Subprogram_Mode := True;
 

gcc/ada/opt.ads

@@ -704,7 +704,7 @@ package Opt is
    Generate_C_Code : Boolean := False;
    --  GNAT
    --  If True, the Cprint circuitry to generate C code output is activated.
-   --  Set True by use of -gnatd.V.
+   --  Set True by use of -gnateg or -gnatd.V.
 
    Generate_CodePeer_Messages : Boolean := False;
    --  GNAT

gcc/ada/switch-c.adb

@@ -585,6 +585,12 @@ package body Switch.C is
                      Ptr := Ptr + 1;
                      Check_Float_Overflow := not Machine_Overflows_On_Target;
 
+                  --  -gnateg (generate C code)
+
+                  when 'g' =>
+                     Generate_C_Code := True;
+                     Ptr := Ptr + 1;
+
                   --  -gnateG (save preprocessor output)
 
                   when 'G' =>