1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S Y S T E M . S T A N D A R D _ L I B R A R Y -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2015, Free Software Foundation, Inc. -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32-- This package is included in all programs. It contains declarations that 33-- are required to be part of every Ada program. A special mechanism is 34-- required to ensure that these are loaded, since it may be the case in 35-- some programs that the only references to these required packages are 36-- from C code or from code generated directly by Gigi, and in both cases 37-- the binder is not aware of such references. 38 39-- System.Standard_Library also includes data that must be present in every 40-- program, in particular data for all the standard exceptions, and also some 41-- subprograms that must be present in every program. 42 43-- The binder unconditionally includes s-stalib.ali, which ensures that this 44-- package and the packages it references are included in all Ada programs, 45-- together with the included data. 46 47pragma Compiler_Unit_Warning; 48 49pragma Polling (Off); 50-- We must turn polling off for this unit, because otherwise we get 51-- elaboration circularities with Ada.Exceptions if polling is on. 52 53with Ada.Unchecked_Conversion; 54 55package System.Standard_Library is 56 pragma Warnings (Off); 57 pragma Preelaborate; 58 pragma Warnings (On); 59 60 subtype Big_String is String (1 .. Positive'Last); 61 pragma Suppress_Initialization (Big_String); 62 -- Type used to obtain string access to given address. Initialization is 63 -- suppressed, since we never want to have variables of this type, and 64 -- we never want to attempt initialiazation of virtual variables of this 65 -- type (e.g. when pragma Normalize_Scalars is used). 66 67 type Big_String_Ptr is access all Big_String; 68 for Big_String_Ptr'Storage_Size use 0; 69 -- We use this access type to pass a pointer to an area of storage to be 70 -- accessed as a string. Of course when this pointer is used, it is the 71 -- responsibility of the accessor to ensure proper bounds. The storage 72 -- size clause ensures we do not allocate variables of this type. 73 74 function To_Ptr is 75 new Ada.Unchecked_Conversion (System.Address, Big_String_Ptr); 76 77 ------------------------------------- 78 -- Exception Declarations and Data -- 79 ------------------------------------- 80 81 type Raise_Action is access procedure; 82 -- A pointer to a procedure used in the Raise_Hook field 83 84 type Exception_Data; 85 type Exception_Data_Ptr is access all Exception_Data; 86 -- An equivalent of Exception_Id that is public 87 88 -- The following record defines the underlying representation of exceptions 89 90 -- WARNING: Any changes to this may need to be reflected in the following 91 -- locations in the compiler and runtime code: 92 93 -- 1. The Internal_Exception routine in s-exctab.adb 94 -- 2. The processing in gigi that tests Not_Handled_By_Others 95 -- 3. Expand_N_Exception_Declaration in Exp_Ch11 96 -- 4. The construction of the exception type in Cstand 97 98 type Exception_Data is record 99 Not_Handled_By_Others : Boolean; 100 -- Normally set False, indicating that the exception is handled in the 101 -- usual way by others (i.e. an others handler handles the exception). 102 -- Set True to indicate that this exception is not caught by others 103 -- handlers, but must be explicitly named in a handler. This latter 104 -- setting is currently used by the Abort_Signal. 105 106 Lang : Character; 107 -- A character indicating the language raising the exception. 108 -- Set to "A" for exceptions defined by an Ada program. 109 -- Set to "C" for imported C++ exceptions. 110 111 Name_Length : Natural; 112 -- Length of fully expanded name of exception 113 114 Full_Name : System.Address; 115 -- Fully expanded name of exception, null terminated 116 -- You can use To_Ptr to convert this to a string. 117 118 HTable_Ptr : Exception_Data_Ptr; 119 -- Hash table pointer used to link entries together in the hash table 120 -- built (by Register_Exception in s-exctab.adb) for converting between 121 -- identities and names. 122 123 Foreign_Data : Address; 124 -- Data for imported exceptions. Not used in the Ada case. This 125 -- represents the address of the RTTI for the C++ case. 126 127 Raise_Hook : Raise_Action; 128 -- This field can be used to place a "hook" on an exception. If the 129 -- value is non-null, then it points to a procedure which is called 130 -- whenever the exception is raised. This call occurs immediately, 131 -- before any other actions taken by the raise (and in particular 132 -- before any unwinding of the stack occurs). 133 end record; 134 135 -- Definitions for standard predefined exceptions defined in Standard, 136 137 -- Why are the NULs necessary here, seems like they should not be 138 -- required, since Gigi is supposed to add a Nul to each name ??? 139 140 Constraint_Error_Name : constant String := "CONSTRAINT_ERROR" & ASCII.NUL; 141 Program_Error_Name : constant String := "PROGRAM_ERROR" & ASCII.NUL; 142 Storage_Error_Name : constant String := "STORAGE_ERROR" & ASCII.NUL; 143 Tasking_Error_Name : constant String := "TASKING_ERROR" & ASCII.NUL; 144 Abort_Signal_Name : constant String := "_ABORT_SIGNAL" & ASCII.NUL; 145 146 Numeric_Error_Name : constant String := "NUMERIC_ERROR" & ASCII.NUL; 147 -- This is used only in the Ada 83 case, but it is not worth having a 148 -- separate version of s-stalib.ads for use in Ada 83 mode. 149 150 Constraint_Error_Def : aliased Exception_Data := 151 (Not_Handled_By_Others => False, 152 Lang => 'A', 153 Name_Length => Constraint_Error_Name'Length, 154 Full_Name => Constraint_Error_Name'Address, 155 HTable_Ptr => null, 156 Foreign_Data => Null_Address, 157 Raise_Hook => null); 158 159 Numeric_Error_Def : aliased Exception_Data := 160 (Not_Handled_By_Others => False, 161 Lang => 'A', 162 Name_Length => Numeric_Error_Name'Length, 163 Full_Name => Numeric_Error_Name'Address, 164 HTable_Ptr => null, 165 Foreign_Data => Null_Address, 166 Raise_Hook => null); 167 168 Program_Error_Def : aliased Exception_Data := 169 (Not_Handled_By_Others => False, 170 Lang => 'A', 171 Name_Length => Program_Error_Name'Length, 172 Full_Name => Program_Error_Name'Address, 173 HTable_Ptr => null, 174 Foreign_Data => Null_Address, 175 Raise_Hook => null); 176 177 Storage_Error_Def : aliased Exception_Data := 178 (Not_Handled_By_Others => False, 179 Lang => 'A', 180 Name_Length => Storage_Error_Name'Length, 181 Full_Name => Storage_Error_Name'Address, 182 HTable_Ptr => null, 183 Foreign_Data => Null_Address, 184 Raise_Hook => null); 185 186 Tasking_Error_Def : aliased Exception_Data := 187 (Not_Handled_By_Others => False, 188 Lang => 'A', 189 Name_Length => Tasking_Error_Name'Length, 190 Full_Name => Tasking_Error_Name'Address, 191 HTable_Ptr => null, 192 Foreign_Data => Null_Address, 193 Raise_Hook => null); 194 195 Abort_Signal_Def : aliased Exception_Data := 196 (Not_Handled_By_Others => True, 197 Lang => 'A', 198 Name_Length => Abort_Signal_Name'Length, 199 Full_Name => Abort_Signal_Name'Address, 200 HTable_Ptr => null, 201 Foreign_Data => Null_Address, 202 Raise_Hook => null); 203 204 pragma Export (C, Constraint_Error_Def, "constraint_error"); 205 pragma Export (C, Numeric_Error_Def, "numeric_error"); 206 pragma Export (C, Program_Error_Def, "program_error"); 207 pragma Export (C, Storage_Error_Def, "storage_error"); 208 pragma Export (C, Tasking_Error_Def, "tasking_error"); 209 pragma Export (C, Abort_Signal_Def, "_abort_signal"); 210 211 Local_Partition_ID : Natural := 0; 212 -- This variable contains the local Partition_ID that will be used when 213 -- building exception occurrences. In distributed mode, it will be 214 -- set by each partition to the correct value during the elaboration. 215 216 type Exception_Trace_Kind is 217 (RM_Convention, 218 -- No particular trace is requested, only unhandled exceptions 219 -- in the environment task (following the RM) will be printed. 220 -- This is the default behavior. 221 222 Every_Raise, 223 -- Denotes every possible raise event, either explicit or due to 224 -- a specific language rule, within the context of a task or not. 225 226 Unhandled_Raise 227 -- Denotes the raise events corresponding to exceptions for which 228 -- there is no user defined handler. 229 ); 230 -- Provide a way to denote different kinds of automatic traces related 231 -- to exceptions that can be requested. 232 233 Exception_Trace : Exception_Trace_Kind := RM_Convention; 234 pragma Atomic (Exception_Trace); 235 -- By default, follow the RM convention 236 237 ----------------- 238 -- Subprograms -- 239 ----------------- 240 241 procedure Abort_Undefer_Direct; 242 pragma Inline (Abort_Undefer_Direct); 243 -- A little procedure that just calls Abort_Undefer.all, for use in 244 -- clean up procedures, which only permit a simple subprogram name. 245 246 procedure Adafinal; 247 -- Performs the Ada Runtime finalization the first time it is invoked. 248 -- All subsequent calls are ignored. 249 250end System.Standard_Library; 251