[thirdparty/gcc.git] / gcc / ada / sem_cat.ads

------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                              S E M _ C A T                               --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--          Copyright (C) 1992-2021, 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.      --
--                                                                          --
------------------------------------------------------------------------------

--  This unit contains the routines used for checking for conformance with
--  the semantic restrictions required for the categorization pragmas:
--
--    Preelaborate
--    Pure
--    Remote_Call_Interface
--    Remote_Types
--    Shared_Passive
--
--  Note that we treat Preelaborate as a categorization pragma, even though
--  strictly, according to RM E.2(2,3), the term does not apply in this case.

with Exp_Tss; use Exp_Tss;
with Types;   use Types;

package Sem_Cat is

   function Has_Stream_Attribute_Definition
     (Typ          : Entity_Id;
      Nam          : TSS_Name_Type;
      At_Any_Place : Boolean := False) return Boolean;
   --  True when there is a attribute definition clause specifying attribute
   --  Nam for Typ. In Ada 2005 mode, returns True only when the attribute
   --  definition clause is visible, unless At_Any_Place is True (in which case
   --  no visibility test is made, and True is returned as long as an attribute
   --  is visible at any place). Note that attribute definition clauses
   --  inherited from parent types are taken into account by this predicate
   --  (to test for presence of an attribute definition clause for one
   --  specific type, excluding inherited definitions, the flags
   --  Has_Specified_Stream_* can be used instead).

   function In_Preelaborated_Unit return Boolean;
   --  Determines if the current scope is within a preelaborated compilation
   --  unit, that is one to which one of the pragmas Preelaborate, Pure,
   --  Shared_Passive, Remote_Types, or inside a unit other than a package
   --  body with pragma Remote_Call_Interface.

   function In_Pure_Unit return Boolean;
   pragma Inline (In_Pure_Unit);
   --  Determines if the current scope is within pure compilation unit,
   --  that is, one to which the pragmas Pure is applied.

   function In_Subprogram_Task_Protected_Unit return Boolean;
   --  Determines if the current scope is within a subprogram, task
   --  or protected unit. Used to validate if the library unit is Pure
   --  (RM 10.2.1(16)).

   procedure Set_Categorization_From_Pragmas (N : Node_Id);
   --  Since validation of categorization dependency is done during Analyze,
   --  categorization flags from following pragmas should be set before
   --  validation begin. N is the N_Compilation_Unit node.

   procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id);
   --  Set categorization flags Pure, Remote_Call_Interface and Remote_Types
   --  on entity E according to those of Scop.

   procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id);
   --  Validate all constraints against declaration of access types in
   --  categorized library units. Usually this is a violation in Pure unit,
   --  Shared_Passive unit. N is the declaration node.

   procedure Validate_Ancestor_Part (N : Node_Id);
   --  Checks that a type given as the ancestor in an extension aggregate
   --  satisfies the restriction of 10.2.1(9).

   procedure Validate_Categorization_Dependency (N : Node_Id; E : Entity_Id);
   --  There are restrictions on lib unit that semantically depends on other
   --  units (RM E.2(5), 10.2.1(11). This procedure checks the restrictions
   --  on categorizations. N is the current unit node, and E is the current
   --  library unit entity.

   procedure Validate_Controlled_Object (E : Entity_Id);
   --  Given an entity for a library level controlled object, check that it is
   --  not in a preelaborated unit (prohibited by RM 10.2.1(9)).

   procedure Validate_Null_Statement_Sequence (N : Node_Id);
   --  Given N, a package body node, check that a handled statement sequence
   --  in a preelaborable body contains no statements other than labels or
   --  null statements, as required by RM 10.2.1(6).

   procedure Validate_Object_Declaration (N : Node_Id);
   --  Given N, an object declaration node, validates all the constraints in
   --  a preelaborable library unit, including creation of task objects etc.
   --  Note that this is called when the corresponding object is frozen since
   --  the checks cannot be made before knowing if the object is imported.

   procedure Validate_RCI_Declarations (P : Entity_Id);
   --  Apply semantic checks given in E2.3(10-14)

   procedure Validate_RCI_Subprogram_Declaration (N : Node_Id);
   --  Check RCI subprogram declarations for illegal inlining and formals not
   --  supporting external streaming.

   procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id);
   --  Checks that Storage_Pool and Storage_Size attribute references are
   --  not applied to remote access-to-class-wide types. Also checks that the
   --  expected type for an allocator cannot be a remote access-to-class-wide
   --  type. Also checks that a remote access-to-class-wide type cannot be an
   --  actual parameter for a generic formal access type. RM E.2.2(17).

   procedure Validate_RT_RAT_Component (N : Node_Id);
   --  Given N, the package library unit declaration node, we should check
   --  against RM:9.95 E.2.2(8): the full view of a type declared in the
   --  visible part of a Remote Types unit has a part that is of a non-remote
   --  access type which has no read/write.

   procedure Validate_Remote_Type_Type_Conversion (N : Node_Id);
   --  Check for remote-type type conversion constraints. First, a value of
   --  a remote access-to-subprogram type can be converted only to another
   --  type conformant remote access-to-subprogram type. Secondly, a value
   --  of a remote access-to-class-wide type can be converted only to another
   --  remote access-to-class-wide type (RM E.2.3(17,20)).

   procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id);
   --  Check validity of declaration if shared passive unit. It should not
   --  contain the declaration of an access-to-object type whose designated
   --  type is a class-wide type ,task type or protected type. E.2.1(7).
   --  T is the entity of the declared type.

   procedure Validate_Static_Object_Name (N : Node_Id);
   --  In the elaboration code of a preelaborated library unit, check that we
   --  do not have the evaluation of a primary that is a name of an object,
   --  unless the name is a static expression (RM 10.2.1(8)). Non-static
   --  constant and variable are the targets, generic parameters are not
   --  are not included because the generic declaration and body are
   --  preelaborable.

   procedure Validate_RACW_Primitives (T : Entity_Id);
   --  Enforce constraints on primitive operations of the designated type of
   --  an RACW. Note that since the complete set of primitive operations of the
   --  designated type needs to be known, we must defer these checks until the
   --  designated type is frozen.

end Sem_Cat;
Commit	Line	Data
996ae0b0 RK	1	------------------------------------------------------------------------------
	2	-- --
	3	-- GNAT COMPILER COMPONENTS --
	4	-- --
	5	-- S E M _ C A T --
	6	-- --
	7	-- S p e c --
	8	-- --
8d0d46f4	9	-- Copyright (C) 1992-2021, Free Software Foundation, Inc. --
996ae0b0 RK	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- --
b5c84c3c	13	-- ware Foundation; either version 3, or (at your option) any later ver- --
996ae0b0 RK	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. See the GNU General Public License --
	17	-- for more details. You should have received a copy of the GNU General --
b5c84c3c RD	18	-- Public License distributed with GNAT; see file COPYING3. If not, go to --
b5c84c3c RD	19	-- http://www.gnu.org/licenses for a complete copy of the license. --
996ae0b0 RK	20	-- --
996ae0b0 RK	21	-- GNAT was originally developed by the GNAT team at New York University. --
71ff80dc	22	-- Extensive contributions were provided by Ada Core Technologies Inc. --
996ae0b0 RK	23	-- --
	24	------------------------------------------------------------------------------
	25
	26	-- This unit contains the routines used for checking for conformance with
	27	-- the semantic restrictions required for the categorization pragmas:
	28	--
	29	-- Preelaborate
29d39651	30	-- Pure
996ae0b0 RK	31	-- Remote_Call_Interface
	32	-- Remote_Types
	33	-- Shared_Passive
	34	--
	35	-- Note that we treat Preelaborate as a categorization pragma, even though
	36	-- strictly, according to RM E.2(2,3), the term does not apply in this case.
	37
468c6c8a ES	38	with Exp_Tss; use Exp_Tss;
468c6c8a ES	39	with Types; use Types;
996ae0b0 RK	40
	41	package Sem_Cat is
	42
468c6c8a	43	function Has_Stream_Attribute_Definition
fe685905 TQ	44	(Typ : Entity_Id;
	45	Nam : TSS_Name_Type;
	46	At_Any_Place : Boolean := False) return Boolean;
468c6c8a ES	47	-- True when there is a attribute definition clause specifying attribute
468c6c8a ES	48	-- Nam for Typ. In Ada 2005 mode, returns True only when the attribute
fe685905	49	-- definition clause is visible, unless At_Any_Place is True (in which case
12a13f01	50	-- no visibility test is made, and True is returned as long as an attribute
fe685905	51	-- is visible at any place). Note that attribute definition clauses
468c6c8a ES	52	-- inherited from parent types are taken into account by this predicate
	53	-- (to test for presence of an attribute definition clause for one
	54	-- specific type, excluding inherited definitions, the flags
fe685905	55	-- Has_Specified_Stream_* can be used instead).
468c6c8a	56
996ae0b0 RK	57	function In_Preelaborated_Unit return Boolean;
	58	-- Determines if the current scope is within a preelaborated compilation
	59	-- unit, that is one to which one of the pragmas Preelaborate, Pure,
	60	-- Shared_Passive, Remote_Types, or inside a unit other than a package
	61	-- body with pragma Remote_Call_Interface.
	62
	63	function In_Pure_Unit return Boolean;
	64	pragma Inline (In_Pure_Unit);
	65	-- Determines if the current scope is within pure compilation unit,
	66	-- that is, one to which the pragmas Pure is applied.
	67
	68	function In_Subprogram_Task_Protected_Unit return Boolean;
	69	-- Determines if the current scope is within a subprogram, task
	70	-- or protected unit. Used to validate if the library unit is Pure
	71	-- (RM 10.2.1(16)).
	72
	73	procedure Set_Categorization_From_Pragmas (N : Node_Id);
fbf5a39b AC	74	-- Since validation of categorization dependency is done during Analyze,
fbf5a39b AC	75	-- categorization flags from following pragmas should be set before
996ae0b0 RK	76	-- validation begin. N is the N_Compilation_Unit node.
996ae0b0 RK	77
fbf5a39b AC	78	procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id);
	79	-- Set categorization flags Pure, Remote_Call_Interface and Remote_Types
	80	-- on entity E according to those of Scop.
	81
996ae0b0 RK	82	procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id);
	83	-- Validate all constraints against declaration of access types in
	84	-- categorized library units. Usually this is a violation in Pure unit,
	85	-- Shared_Passive unit. N is the declaration node.
	86
	87	procedure Validate_Ancestor_Part (N : Node_Id);
	88	-- Checks that a type given as the ancestor in an extension aggregate
	89	-- satisfies the restriction of 10.2.1(9).
	90
	91	procedure Validate_Categorization_Dependency (N : Node_Id; E : Entity_Id);
	92	-- There are restrictions on lib unit that semantically depends on other
	93	-- units (RM E.2(5), 10.2.1(11). This procedure checks the restrictions
	94	-- on categorizations. N is the current unit node, and E is the current
	95	-- library unit entity.
	96
	97	procedure Validate_Controlled_Object (E : Entity_Id);
	98	-- Given an entity for a library level controlled object, check that it is
	99	-- not in a preelaborated unit (prohibited by RM 10.2.1(9)).
	100
	101	procedure Validate_Null_Statement_Sequence (N : Node_Id);
	102	-- Given N, a package body node, check that a handled statement sequence
	103	-- in a preelaborable body contains no statements other than labels or
	104	-- null statements, as required by RM 10.2.1(6).
	105
	106	procedure Validate_Object_Declaration (N : Node_Id);
	107	-- Given N, an object declaration node, validates all the constraints in
	108	-- a preelaborable library unit, including creation of task objects etc.
	109	-- Note that this is called when the corresponding object is frozen since
	110	-- the checks cannot be made before knowing if the object is imported.
	111
	112	procedure Validate_RCI_Declarations (P : Entity_Id);
d18bbd25	113	-- Apply semantic checks given in E2.3(10-14)
996ae0b0 RK	114
996ae0b0 RK	115	procedure Validate_RCI_Subprogram_Declaration (N : Node_Id);
349ff68f AC	116	-- Check RCI subprogram declarations for illegal inlining and formals not
349ff68f AC	117	-- supporting external streaming.
996ae0b0 RK	118
	119	procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id);
	120	-- Checks that Storage_Pool and Storage_Size attribute references are
d18bbd25 AC	121	-- not applied to remote access-to-class-wide types. Also checks that the
d18bbd25 AC	122	-- expected type for an allocator cannot be a remote access-to-class-wide
072c5071 AC	123	-- type. Also checks that a remote access-to-class-wide type cannot be an
072c5071 AC	124	-- actual parameter for a generic formal access type. RM E.2.2(17).
996ae0b0	125
996ae0b0 RK	126	procedure Validate_RT_RAT_Component (N : Node_Id);
	127	-- Given N, the package library unit declaration node, we should check
	128	-- against RM:9.95 E.2.2(8): the full view of a type declared in the
	129	-- visible part of a Remote Types unit has a part that is of a non-remote
	130	-- access type which has no read/write.
	131
	132	procedure Validate_Remote_Type_Type_Conversion (N : Node_Id);
	133	-- Check for remote-type type conversion constraints. First, a value of
	134	-- a remote access-to-subprogram type can be converted only to another
	135	-- type conformant remote access-to-subprogram type. Secondly, a value
	136	-- of a remote access-to-class-wide type can be converted only to another
	137	-- remote access-to-class-wide type (RM E.2.3(17,20)).
	138
	139	procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id);
	140	-- Check validity of declaration if shared passive unit. It should not
	141	-- contain the declaration of an access-to-object type whose designated
	142	-- type is a class-wide type ,task type or protected type. E.2.1(7).
	143	-- T is the entity of the declared type.
	144
	145	procedure Validate_Static_Object_Name (N : Node_Id);
23b86353 AC	146	-- In the elaboration code of a preelaborated library unit, check that we
	147	-- do not have the evaluation of a primary that is a name of an object,
	148	-- unless the name is a static expression (RM 10.2.1(8)). Non-static
	149	-- constant and variable are the targets, generic parameters are not
996ae0b0 RK	150	-- are not included because the generic declaration and body are
	151	-- preelaborable.
	152
468c6c8a ES	153	procedure Validate_RACW_Primitives (T : Entity_Id);
	154	-- Enforce constraints on primitive operations of the designated type of
	155	-- an RACW. Note that since the complete set of primitive operations of the
	156	-- designated type needs to be known, we must defer these checks until the
87ace727	157	-- designated type is frozen.
468c6c8a	158
996ae0b0	159	end Sem_Cat;