par-prag.adb (Prag): Add dummy entry for pragma Compile_Time_Error

2007-04-06  Robert Dewar  <dewar@adacore.com>
	    Javier Miranda  <miranda@adacore.com>
	    Bob Duff  <duff@adacore.com>
	    Vincent Celier  <celier@adacore.com>

	* par-prag.adb (Prag): Add dummy entry for pragma Compile_Time_Error
	(Extensions_Allowed): No longer sets Ada_Version
	Entry for pragma Unreferenced_Objects

	* sem_prag.adb (Analyze_Pragma, case Priority): Force with of
	system.tasking if pragma priority used in a procedure
	(Analyze_Pragma, case Warning): Handle dot warning switches
	(Process_Compile_Time_Warning_Or_Error): New procedure
	(Analyze_Pragma): Add processing for Compile_Time_Error
	Add support for extra arguments External_Name and Link_Name.
	Remove code associated with pragmas CPP_Virtual and CPP_Vtable.
	(Process_Import_Or_Interface): Add support for the use of pragma Import
	with tagged types.
	(Extensions_Allowed): No longer affects Ada_Version
	(Analyze_Pragma): Split Is_Abstract flag into Is_Abstract_Subprogram and
	Is_Abstract_Type. Make sure these are called only when appropriate.
	Add processing for pragma Unreferenced_Objects

	* snames.h, snames.ads, snames.adb: Add entry for pragma
	Compile_Time_Error
	Add new standard name Minimum_Binder_Options for new gprmake
	Add new standard names for gprmake: Archive_Suffix,
	Library_Auto_Init_Supported, Library_Major_Minor_Id_Supported,
	Library_Support, Library_Version_Options,
	Shared_Library_Minimum_Options,
	Shared_Library_Prefix, Shared_Library_Suffix, Symbolic_Link_Supported.
	Change Name_Call to Name_uCall so that it cannot clash with a legal
	subprogram name.
	Add new standard names Mapping_Spec_Suffix and Mapping_Body_Suffix
	Append C_Plus_Plus to convention identifiers as synonym for CPP
	Add new standard names Stack and Builder_Switches
	Add new standard names: Compiler_Minimum_Options, Global_Config_File,
	Library_Builder, Local_Config_File, Objects_Path, Objects_Path_File,
	Run_Path_Option, Toolchain_Version.
	Entry for pragma Unreferenced_Objects

	* switch-c.adb (Scan_Front_End_Switches): Store correct -gnateD
	switches, without repetition of "eD". Make sure that last character of
	-gnatep= switch is not taken as -gnat switch character.
	Complete rewrite of circuit for handling saving compilation options
	Occasioned by need to support dot switchs for -gnatw, but cleans up
	things in general.
	-gnatX does not affect Ada_Version
	Include -gnatyA in -gnatg style switches

	* sem_warn.ads, sem_warn.adb (Output_Unreferenced_Messages): Exclude
	warnings on return objects.
	(Warn_On_Useless_Assignment): Exclude warnings on return objects
	(Set_Dot_Warning_Switch): New procedure
	(Check_References): Add missing case of test for
	Has_Pragma_Unreferenced_Objects
	(Output_Unreferenced_Messages): Implement effect of new pragma
	Unreferenced_Objects, remove special casing of limited controlled
	variables.

From-SVN: r123588

gcc/ada/par-prag.adb

@@ -376,14 +376,10 @@ begin
 
          if Chars (Expression (Arg1)) = Name_On then
             Extensions_Allowed := True;
-            Ada_Version := Ada_Version_Type'Last;
          else
             Extensions_Allowed := False;
-            Ada_Version := Ada_Version_Type'Min (Ada_Version, Ada_95);
          end if;
 
-         Ada_Version_Explicit := Ada_Version;
-
       ----------------
       -- List (2.8) --
       ----------------
@@ -1058,6 +1054,7 @@ begin
            Pragma_Atomic                        |
            Pragma_Atomic_Components             |
            Pragma_Attach_Handler                |
+           Pragma_Compile_Time_Error            |
            Pragma_Compile_Time_Warning          |
            Pragma_Convention_Identifier         |
            Pragma_CPP_Class                     |
@@ -1179,6 +1176,7 @@ begin
            Pragma_Unimplemented_Unit            |
            Pragma_Universal_Data                |
            Pragma_Unreferenced                  |
+           Pragma_Unreferenced_Objects          |
            Pragma_Unreserve_All_Interrupts      |
            Pragma_Unsuppress                    |
            Pragma_Use_VADS_Size                 |

gcc/ada/sem_warn.adb

@@ -392,6 +392,7 @@ package body Sem_Warn is
                      --  or if it is a parameter, to the corresponding spec.
 
                      if Has_Pragma_Unreferenced (E1)
+                       or else Has_Pragma_Unreferenced_Objects (Etype (E1))
                        or else (Is_Formal (E1)
                                   and then Present (Spec_Entity (E1))
                                   and then
@@ -1641,6 +1642,7 @@ package body Sem_Warn is
                   then
                      if Warn_On_Modified_Unread
                        and then not Is_Imported (E)
+                       and then not Is_Return_Object (E)
 
                         --  Suppress message for aliased or renamed variables,
                         --  since there may be other entities that read the
@@ -1658,20 +1660,12 @@ package body Sem_Warn is
                   --  Normal case of neither assigned nor read
 
                   else
-                     --  We suppress the message for limited controlled types,
-                     --  to catch the common design pattern (known as RAII, or
-                     --  Resource Acquisition Is Initialization) which uses
-                     --  such types solely for their initialization and
-                     --  finalization semantics.
-
-                     if Is_Controlled (Etype (E))
-                       and then Is_Limited_Type (Etype (E))
-                     then
-                        null;
+                     --  We suppress the message for types for which a valid
+                     --  pragma Unreferenced_Objects has been given, otherwise
+                     --  we go ahead and give the message.
 
-                     --  Normal case where we want to give message
+                     if not Has_Pragma_Unreferenced_Objects (Etype (E)) then
 
-                     else
                         --  Distinguish renamed case in message
 
                         if Present (Renamed_Object (E))
@@ -1740,6 +1734,26 @@ package body Sem_Warn is
       end loop;
    end Output_Unreferenced_Messages;
 
+   ----------------------------
+   -- Set_Dot_Warning_Switch --
+   ----------------------------
+
+   function Set_Dot_Warning_Switch (C : Character) return Boolean is
+   begin
+      case C is
+         when 'x' =>
+            Warn_On_Non_Local_Exception         := True;
+
+         when 'X' =>
+            Warn_On_Non_Local_Exception         := False;
+
+         when others =>
+            return False;
+      end case;
+
+      return True;
+   end Set_Dot_Warning_Switch;
+
    ------------------------
    -- Set_Warning_Switch --
    ------------------------
@@ -1761,6 +1775,7 @@ package body Sem_Warn is
             Warn_On_Export_Import               := True;
             Warn_On_Modified_Unread             := True;
             Warn_On_No_Value_Assigned           := True;
+            Warn_On_Non_Local_Exception         := True;
             Warn_On_Obsolescent_Feature         := True;
             Warn_On_Questionable_Missing_Parens := True;
             Warn_On_Redundant_Constructs        := True;
@@ -1784,8 +1799,9 @@ package body Sem_Warn is
             Warn_On_Hiding                      := False;
             Warn_On_Modified_Unread             := False;
             Warn_On_No_Value_Assigned           := False;
+            Warn_On_Non_Local_Exception         := False;
             Warn_On_Obsolescent_Feature         := False;
-            Warn_On_Questionable_Missing_Parens := True;
+            Warn_On_Questionable_Missing_Parens := False;
             Warn_On_Redundant_Constructs        := False;
             Warn_On_Unchecked_Conversion        := False;
             Warn_On_Unrecognized_Pragma         := False;
@@ -2409,11 +2425,12 @@ package body Sem_Warn is
    --  Start of processing for Warn_On_Useless_Assignment
 
    begin
-      --  Check if this is a case we want to warn on, a variable with
-      --  the last assignment field set, with warnings enabled, and
-      --  which is not imported or exported.
+      --  Check if this is a case we want to warn on, a variable with the
+      --  last assignment field set, with warnings enabled, and which is
+      --  not imported or exported.
 
       if Ekind (Ent) = E_Variable
+        and then not Is_Return_Object (Ent)
         and then Present (Last_Assignment (Ent))
         and then not Warnings_Off (Ent)
         and then not Has_Pragma_Unreferenced (Ent)

gcc/ada/sem_warn.ads

@@ -37,9 +37,16 @@ package Sem_Warn is
    --------------------
 
    function Set_Warning_Switch (C : Character) return Boolean;
-   --  This function sets the warning switch or switches corresponding to
-   --  the given character. It is used for processing a -gnatw switch on the
-   --  command line, or a string literal in pragma Warnings.
+   --  This function sets the warning switch or switches corresponding to the
+   --  given character. It is used to process a -gnatw switch on the command
+   --  line, or a character in a string literal in pragma Warnings. Returns
+   --  True for valid warning character C, False for invalid character.
+
+   function Set_Dot_Warning_Switch (C : Character) return Boolean;
+   --  This function sets the warning switch or switches corresponding to the
+   --  given character preceded by a dot. Used to process a -gnatw. switch on
+   --  the command line or .C in a string literal in pragma Warnings. Returns
+   --  True for valid warning character C, False for invalid character.
 
    ------------------------------------------
    -- Routines to Handle Unused References --

gcc/ada/snames.adb

@@ -139,7 +139,7 @@ package body Snames is
      "partition#" &
      "partition_interface#" &
      "ras#" &
-     "call#" &
+     "_call#" &
      "rci_name#" &
      "receiver#" &
      "result#" &
@@ -178,6 +178,7 @@ package body Snames is
      "ada_2005#" &
      "assertion_policy#" &
      "c_pass_by_copy#" &
+     "compile_time_error#" &
      "compile_time_warning#" &
      "component_alignment#" &
      "convention_identifier#" &
@@ -317,6 +318,7 @@ package body Snames is
      "unchecked_union#" &
      "unimplemented_unit#" &
      "unreferenced#" &
+     "unreferenced_objects#" &
      "unreserve_all_interrupts#" &
      "volatile#" &
      "volatile_components#" &
@@ -333,6 +335,7 @@ package body Snames is
      "asm#" &
      "assembly#" &
      "default#" &
+     "c_plus_plus#" &
      "dll#" &
      "win32#" &
      "as_is#" &
@@ -664,13 +667,16 @@ package body Snames is
      "ada_roots#" &
      "archive_builder#" &
      "archive_indexer#" &
+     "archive_suffix#" &
      "binder#" &
      "binder_driver#" &
      "body_suffix#" &
      "builder#" &
+     "builder_switches#" &
      "compiler#" &
      "compiler_driver#" &
      "compiler_kind#" &
+     "compiler_minimum_options#" &
      "compiler_pic_option#" &
      "compute_dependency#" &
      "config_body_file_name#" &
@@ -695,6 +701,7 @@ package body Snames is
      "finder#" &
      "global_compiler_switches#" &
      "global_configuration_pragmas#" &
+     "global_config_file#" &
      "gnatls#" &
      "gnatstub#" &
      "implementation#" &
@@ -707,32 +714,47 @@ package body Snames is
      "language_processing#" &
      "languages#" &
      "library_ali_dir#" &
-     "library_dir#" &
      "library_auto_init#" &
+     "library_auto_init_supported#" &
+     "library_builder#" &
+     "library_dir#" &
      "library_gcc#" &
      "library_interface#" &
      "library_kind#" &
      "library_name#" &
+     "library_major_minor_id_supported#" &
      "library_options#" &
      "library_reference_symbol_file#" &
      "library_src_dir#" &
+     "library_support#" &
      "library_symbol_file#" &
      "library_symbol_policy#" &
      "library_version#" &
+     "library_version_options#" &
      "linker#" &
      "linker_executable_option#" &
      "linker_lib_dir_option#" &
      "linker_lib_name_option#" &
+     "local_config_file#" &
      "local_configuration_pragmas#" &
      "locally_removed_files#" &
      "mapping_file_switches#" &
+     "mapping_spec_suffix#" &
+     "mapping_body_suffix#" &
      "metrics#" &
+     "minimum_binder_options#" &
      "naming#" &
+     "objects_path#" &
+     "objects_path_file#" &
      "object_dir#" &
      "pretty_printer#" &
      "project#" &
      "roots#" &
+     "run_path_option#" &
      "runtime_project#" &
+     "shared_library_minimum_options#" &
+     "shared_library_prefix#" &
+     "shared_library_suffix#" &
      "separate_suffix#" &
      "source_dirs#" &
      "source_files#" &
@@ -742,7 +764,10 @@ package body Snames is
      "specification#" &
      "specification_exceptions#" &
      "specification_suffix#" &
+     "stack#" &
      "switches#" &
+     "symbolic_link_supported#" &
+     "toolchain_version#" &
      "unaligned_valid#" &
      "interface#" &
      "overriding#" &
@@ -976,14 +1001,16 @@ package body Snames is
 
       Convention_Identifiers.Init;
 
-      Convention_Identifiers.Append ((Name_Asm,      Convention_Assembler));
-      Convention_Identifiers.Append ((Name_Assembly, Convention_Assembler));
+      Convention_Identifiers.Append ((Name_Asm,         Convention_Assembler));
+      Convention_Identifiers.Append ((Name_Assembly,    Convention_Assembler));
+
+      Convention_Identifiers.Append ((Name_Default,     Convention_C));
+      Convention_Identifiers.Append ((Name_External,    Convention_C));
 
-      Convention_Identifiers.Append ((Name_Default,  Convention_C));
-      Convention_Identifiers.Append ((Name_External, Convention_C));
+      Convention_Identifiers.Append ((Name_C_Plus_Plus, Convention_CPP));
 
-      Convention_Identifiers.Append ((Name_DLL,      Convention_Stdcall));
-      Convention_Identifiers.Append ((Name_Win32,    Convention_Stdcall));
+      Convention_Identifiers.Append ((Name_DLL,         Convention_Stdcall));
+      Convention_Identifiers.Append ((Name_Win32,       Convention_Stdcall));
    end Initialize;
 
    -----------------------