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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M _ P R A G --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2013, 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- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- Pragma handling is isolated in a separate package
-- (logically this processing belongs in chapter 4)
with Namet; use Namet;
with Opt; use Opt;
with Snames; use Snames;
with Types; use Types;
package Sem_Prag is
-- The following table lists all pragmas that act as an assertion
-- expression.
Assertion_Expression_Pragma : constant array (Pragma_Id) of Boolean :=
(Pragma_Assert => True,
Pragma_Assert_And_Cut => True,
Pragma_Assume => True,
Pragma_Check => True,
Pragma_Contract_Cases => True,
Pragma_Initial_Condition => True,
Pragma_Invariant => True,
Pragma_Loop_Invariant => True,
Pragma_Loop_Variant => True,
Pragma_Post => True,
Pragma_Post_Class => True,
Pragma_Postcondition => True,
Pragma_Pre => True,
Pragma_Pre_Class => True,
Pragma_Precondition => True,
Pragma_Predicate => True,
Pragma_Refined_Post => True,
Pragma_Test_Case => True,
Pragma_Type_Invariant => True,
Pragma_Type_Invariant_Class => True,
others => False);
-- The following table lists all the implementation-defined pragmas that
-- may apply to a body stub (no language defined pragmas apply). The table
-- should be synchronized with Aspect_On_Body_Or_Stub_OK in unit Aspects if
-- the pragmas below implement an aspect.
Pragma_On_Body_Or_Stub_OK : constant array (Pragma_Id) of Boolean :=
(Pragma_Refined_Depends => True,
Pragma_Refined_Global => True,
Pragma_Refined_Post => True,
Pragma_SPARK_Mode => True,
Pragma_Warnings => True,
others => False);
-----------------
-- Subprograms --
-----------------
procedure Analyze_Pragma (N : Node_Id);
-- Analyze procedure for pragma reference node N
procedure Analyze_Contract_Cases_In_Decl_Part (N : Node_Id);
-- Perform full analysis and expansion of delayed pragma Contract_Cases
procedure Analyze_Depends_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Depends. This routine is also
-- capable of performing basic analysis of pragma Refined_Depends.
procedure Analyze_External_Property_In_Decl_Part
(N : Node_Id;
Expr_Val : out Boolean);
-- Perform full analysis of delayed pragmas Async_Readers, Async_Writers,
-- Effective_Reads and Effective_Writes. Flag Expr_Val contains the Boolean
-- argument of the pragma or a default True if no argument is present.
procedure Analyze_Global_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Global. This routine is also
-- capable of performing basic analysis of pragma Refind_Global.
procedure Analyze_Initial_Condition_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Initial_Condition
procedure Analyze_Initializes_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Initializes
procedure Analyze_Pre_Post_Condition_In_Decl_Part
(Prag : Node_Id;
Subp_Id : Entity_Id);
-- Perform preanalysis of a [refined] precondition or postcondition that
-- appears on a subprogram declaration or body [stub]. Prag denotes the
-- pragma, Subp_Id is the entity of the related subprogram. The preanalysis
-- of the expression is done as "spec expression" (see section "Handling
-- of Default and Per-Object Expressions in Sem).
procedure Analyze_Refined_Depends_In_Decl_Part (N : Node_Id);
-- Preform full analysis of delayed pragma Refined_Depends. This routine
-- uses Analyze_Depends_In_Decl_Part as a starting point, then performs
-- various consistency checks between Depends and Refined_Depends.
procedure Analyze_Refined_Global_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Refined_Global. This routine
-- uses Analyze_Global_In_Decl_Part as a starting point, then performs
-- various consistency checks between Global and Refined_Global.
procedure Analyze_Refined_State_In_Decl_Part (N : Node_Id);
-- Perform full analysis of delayed pragma Refined_State
procedure Analyze_Test_Case_In_Decl_Part (N : Node_Id; S : Entity_Id);
-- Perform preanalysis of pragma Test_Case that applies to a subprogram
-- declaration. Parameter N denotes the pragma, S is the entity of the
-- related subprogram. The preanalysis of the expression is done as "spec
-- expression" (see section "Handling of Default and Per-Object Expressions
-- in Sem).
procedure Check_Applicable_Policy (N : Node_Id);
-- N is either an N_Aspect or an N_Pragma node. There are two cases. If
-- the name of the aspect or pragma is not one of those recognized as
-- an assertion kind by an Assertion_Policy pragma, then the call has
-- no effect. Note that in the case of a pragma derived from an aspect,
-- the name we use for the purpose of this procedure is the aspect name,
-- which may be different from the pragma name (e.g. Precondition for
-- Pre aspect). In addition, 'Class aspects are recognized (and the
-- corresponding special names used in the processing).
--
-- If the name is a valid assertion kind name, then the Check_Policy pragma
-- chain is checked for a matching entry (or for an Assertion entry which
-- matches all possibilities). If a matching entry is found then the policy
-- is checked. If it is On or Check, then the Is_Checked flag is set in
-- the aspect or pragma node. If it is Off, Ignore, or Disable, then the
-- Is_Ignored flag is set in the aspect or pragma node. Additionally for
-- policy Disable, the Is_Disabled flag is set.
--
-- If no matching Check_Policy pragma is found then the effect depends on
-- whether -gnata was used, if so, then the call has no effect, otherwise
-- Is_Ignored (but not Is_Disabled) is set True.
procedure Check_External_Properties
(Item : Node_Id;
AR : Boolean;
AW : Boolean;
ER : Boolean;
EW : Boolean);
-- Flags AR, AW, ER and EW denote the static values of external properties
-- Async_Readers, Async_Writers, Effective_Reads and Effective_Writes. Item
-- is the related variable or state. Ensure legality of the combination and
-- issue an error for an illegal combination.
procedure Check_Missing_Part_Of (Item_Id : Entity_Id);
-- Determine whether the placement within the state space of an abstract
-- state, variable or package instantiation denoted by Item_Id requires the
-- use of indicator/option Part_Of. If this is the case, emit an error.
function Delay_Config_Pragma_Analyze (N : Node_Id) return Boolean;
-- N is a pragma appearing in a configuration pragma file. Most such
-- pragmas are analyzed when the file is read, before parsing and analyzing
-- the main unit. However, the analysis of certain pragmas results in
-- adding information to the compiled main unit, and this cannot be done
-- till the main unit is processed. Such pragmas return True from this
-- function and in Frontend pragmas where Delay_Config_Pragma_Analyze is
-- True have their analysis delayed until after the main program is parsed
-- and analyzed.
function Get_SPARK_Mode_From_Pragma (N : Node_Id) return SPARK_Mode_Type;
-- Given a pragma SPARK_Mode node, return corresponding mode id
procedure Initialize;
-- Initializes data structures used for pragma processing. Must be called
-- before analyzing each new main source program.
function Is_Config_Static_String (Arg : Node_Id) return Boolean;
-- This is called for a configuration pragma that requires either string
-- literal or a concatenation of string literals. We cannot use normal
-- static string processing because it is too early in the case of the
-- pragma appearing in a configuration pragmas file. If Arg is of an
-- appropriate form, then this call obtains the string (doing any necessary
-- concatenations) and places it in Name_Buffer, setting Name_Len to its
-- length, and then returns True. If it is not of the correct form, then an
-- appropriate error message is posted, and False is returned.
function Is_Elaboration_SPARK_Mode (N : Node_Id) return Boolean;
-- Determine whether pragma SPARK_Mode appears in the statement part of a
-- package body.
function Is_Non_Significant_Pragma_Reference (N : Node_Id) return Boolean;
-- The node N is a node for an entity and the issue is whether the
-- occurrence is a reference for the purposes of giving warnings about
-- unreferenced variables. This function returns True if the reference is
-- not a reference from this point of view (e.g. the occurrence in a pragma
-- Pack) and False if it is a real reference (e.g. the occurrence in a
-- pragma Export);
function Is_Pragma_String_Literal (Par : Node_Id) return Boolean;
-- Given an N_Pragma_Argument_Association node, Par, which has the form of
-- an operator symbol, determines whether or not it should be treated as an
-- string literal. This is called by Sem_Ch6.Analyze_Operator_Symbol. If
-- True is returned, the argument is converted to a string literal. If
-- False is returned, then the argument is treated as an entity reference
-- to the operator.
function Is_Private_SPARK_Mode (N : Node_Id) return Boolean;
-- Determine whether pragma SPARK_Mode appears in the private part of a
-- package.
function Is_Valid_Assertion_Kind (Nam : Name_Id) return Boolean;
-- Returns True if Nam is one of the names recognized as a valid assertion
-- kind by the Assertion_Policy pragma. Note that the 'Class cases are
-- represented by the corresponding special names Name_uPre, Name_uPost,
-- Name_uInviarnat, and Name_uType_Invariant (_Pre, _Post, _Invariant,
-- and _Type_Invariant).
procedure Make_Aspect_For_PPC_In_Gen_Sub_Decl (Decl : Node_Id);
-- This routine makes aspects from precondition or postcondition pragmas
-- that appear within a generic subprogram declaration. Decl is the generic
-- subprogram declaration node. Note that the aspects are attached to the
-- generic copy and also to the orginal tree.
procedure Process_Compilation_Unit_Pragmas (N : Node_Id);
-- Called at the start of processing compilation unit N to deal with any
-- special issues regarding pragmas. In particular, we have to deal with
-- Suppress_All at this stage, since it can appear after the unit instead
-- of before (actually we allow it to appear anywhere).
procedure Relocate_Pragmas_To_Body
(Subp_Body : Node_Id;
Target_Body : Node_Id := Empty);
-- Resocate all pragmas that follow and apply to subprogram body Subp_Body
-- to its own declaration list. Candidate pragmas are classified in table
-- Pragma_On_Body_Or_Stub_OK. If Target_Body is set, the pragma are moved
-- to the declarations of Target_Body. This formal should be set when
-- dealing with subprogram body stubs or expression functions.
procedure Set_Encoded_Interface_Name (E : Entity_Id; S : Node_Id);
-- This routine is used to set an encoded interface name. The node S is an
-- N_String_Literal node for the external name to be set, and E is an
-- entity whose Interface_Name field is to be set. In the normal case where
-- S contains a name that is a valid C identifier, then S is simply set as
-- the value of the Interface_Name. Otherwise it is encoded. See the body
-- for details of the encoding. This encoding is only done on VMS systems,
-- since it seems pretty silly, but is needed to pass some dubious tests in
-- the test suite.
end Sem_Prag;