bindgen.adb (Gen_Main_C): declare the ensure_reference variable as volatile...

2006-02-13  Joel Brobecker  <brobecke@adacore.com>

	* bindgen.adb (Gen_Main_C): declare the ensure_reference variable as
	volatile, to tell the compiler to preserve this variable at any level
	of optimization.
	(Gen_Versions_Ada): Temporarily work around codegen bug.

From-SVN: r111045

gcc/ada/bindgen.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1992-2005, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2006, 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- --
@@ -347,7 +347,7 @@ package body Bindgen is
 
    procedure Gen_Adafinal_C is
    begin
-      WBI ("void " & Ada_Final_Name.all & " () {");
+      WBI ("void " & Ada_Final_Name.all & " (void) {");
       WBI ("   system__standard_library__adafinal ();");
       WBI ("}");
       WBI ("");
@@ -523,7 +523,8 @@ package body Bindgen is
          WBI ("         Unreserve_All_Interrupts : Integer;");
          WBI ("         Exception_Tracebacks     : Integer;");
          WBI ("         Zero_Cost_Exceptions     : Integer;");
-         WBI ("         Detect_Blocking          : Integer);");
+         WBI ("         Detect_Blocking          : Integer;");
+         WBI ("         Default_Stack_Size       : Integer);");
          WBI ("      pragma Import (C, Set_Globals, ""__gnat_set_globals"");");
 
          --  Import entry point for elaboration time signal handler
@@ -632,6 +633,12 @@ package body Bindgen is
             Set_Int (0);
          end if;
 
+         Set_String (",");
+         Write_Statement_Buffer;
+
+         Set_String ("         Default_Stack_Size       => ");
+         Set_Int (Default_Stack_Size);
+
          Set_String (");");
          Write_Statement_Buffer;
 
@@ -876,10 +883,18 @@ package body Bindgen is
             Set_Int (0);
          end if;
 
-         Set_String (");");
+         Set_String (",");
          Tab_To (24);
          Set_String ("/* Detect_Blocking            */");
          Write_Statement_Buffer;
+
+         Set_String ("      ");
+         Set_Int    (Default_Stack_Size);
+         Set_String (");");
+         Tab_To (24);
+         Set_String ("/* Default_Stack_Size     */");
+         Write_Statement_Buffer;
+
          WBI ("");
 
          --  Install elaboration time signal handler
@@ -1334,10 +1349,15 @@ package body Bindgen is
       --  The reference stops Ada_Main_Program_Name from being optimized
       --  away by smart linkers, such as the AiX linker.
 
+      --  Because this variable is unused, we make this variable "aliased"
+      --  with a pragma Volatile in order to tell the compiler to preserve
+      --  this variable at any level of optimization.
+
       if Bind_Main_Program then
          WBI
-           ("      Ensure_Reference : System.Address := " &
+           ("      Ensure_Reference : aliased System.Address := " &
             "Ada_Main_Program_Name'Address;");
+         WBI ("      pragma Volatile (Ensure_Reference);");
          WBI ("");
       end if;
 
@@ -1471,7 +1491,7 @@ package body Bindgen is
       --  Case of no command line arguments on target
 
       else
-         Write_Statement_Buffer (" ()");
+         Write_Statement_Buffer (" (void)");
       end if;
 
       WBI ("{");
@@ -1482,8 +1502,13 @@ package body Bindgen is
       --  place). The reference stops Ada_Main_Program_Name from being
       --  optimized away by smart linkers, such as the AiX linker.
 
+      --  Because this variable is unused, we declare this variable as
+      --  volatile in order to tell the compiler to preserve it at any
+      --  level of optimization.
+
       if Bind_Main_Program then
-         WBI ("   char *ensure_reference __attribute__ ((__unused__)) = " &
+         WBI ("   char * volatile ensure_reference " &
+              "__attribute__ ((__unused__)) = " &
               "__gnat_ada_main_program_name;");
          WBI ("");
 
@@ -1826,7 +1851,13 @@ package body Bindgen is
 
          if With_DECGNAT then
             Name_Len := 0;
-            Add_Str_To_Name_Buffer ("-ldecgnat");
+
+            if Opt.Shared_Libgnat then
+               Add_Str_To_Name_Buffer (Shared_Lib ("decgnat"));
+            else
+               Add_Str_To_Name_Buffer ("-ldecgnat");
+            end if;
+
             Write_Linker_Option;
          end if;
 
@@ -2229,7 +2260,7 @@ package body Bindgen is
       WBI ("extern void __gnat_set_globals");
       WBI ("  (int, int, char, char, char, char,");
       WBI ("   const char *, const char *,");
-      WBI ("   int, int, int, int, int);");
+      WBI ("   int, int, int, int, int, int);");
 
       if Use_Pragma_Linker_Constructor then
          WBI ("extern void " & Ada_Final_Name.all &
@@ -2361,7 +2392,7 @@ package body Bindgen is
 
       if Suppress_Standard_Library_On_Target then
          WBI ("");
-         WBI ("void __gnat_break_start () {}");
+         WBI ("void __gnat_break_start (void) {}");
       end if;
 
       --  Generate the __gnat_version and __gnat_ada_main_program_name info
@@ -2507,7 +2538,13 @@ package body Bindgen is
       end loop;
 
       WBI ("");
-      Ubuf := "u00000";
+
+      --  We used to have more complex code: Ubuf := "u00000";
+      --  which was being miscompiled, so use simpler code instead:
+
+      for J in Ubuf'First + 1 .. Ubuf'Last loop
+         Ubuf (J) := '0';
+      end loop;
 
       for U in Units.First .. Units.Last loop
          Increment_Ubuf;