gcc/ada/sem_cat.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              S E M _ C A T                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2008, 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.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
  19 -- http://www.gnu.org/licenses for a complete copy of the license.          --
  20 --                                                                          --
  21 -- GNAT was originally developed  by the GNAT team at  New York University. --
  22 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  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
  30 --    Pure,
  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
  38 with Exp_Tss; use Exp_Tss;
  39 with Types;   use Types;
  40
  41 package Sem_Cat is
  42
  43    function Has_Stream_Attribute_Definition
  44      (Typ          : Entity_Id;
  45       Nam          : TSS_Name_Type;
  46       At_Any_Place : Boolean := False) return Boolean;
  47    --  True when there is a attribute definition clause specifying attribute
  48    --  Nam for Typ. In Ada 2005 mode, returns True only when the attribute
  49    --  definition clause is visible, unless At_Any_Place is True (in which case
  50    --  no visibility test is made, and True is returned as long as an attribute
  51    --  is visible at any place). Note that attribute definition clauses
  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
  55    --  Has_Specified_Stream_* can be used instead).
  56
  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);
  74    --  Since validation of categorization dependency is done during Analyze,
  75    --  categorization flags from following pragmas should be set before
  76    --  validation begin. N is the N_Compilation_Unit node.
  77
  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
  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);
 113    --  Apply semantic checks given in  E2.3(10-14)
 114
 115    procedure Validate_RCI_Subprogram_Declaration (N : Node_Id);
 116    --  Check for RCI unit subprogram declarations with respect to
 117    --  in-lined subprogram and subprogram with access parameter or
 118    --  limited type parameter without Read and Write.
 119
 120    procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id);
 121    --  Checks that Storage_Pool and Storage_Size attribute references are
 122    --  not applied to remote access-to-class-wide types. And the expected
 123    --  type for an allocator shall not be a remote access-to-class-wide
 124    --  type. And a remote access-to-class-wide type shall not be an actual
 125    --  parameter for a generic formal access type. RM E.2.3(22).
 126
 127    procedure Validate_RT_RAT_Component (N : Node_Id);
 128    --  Given N, the package library unit declaration node, we should check
 129    --  against RM:9.95 E.2.2(8): the full view of a type declared in the
 130    --  visible part of a Remote Types unit has a part that is of a non-remote
 131    --  access type which has no read/write.
 132
 133    procedure Validate_Remote_Type_Type_Conversion (N : Node_Id);
 134    --  Check for remote-type type conversion constraints. First, a value of
 135    --  a remote access-to-subprogram type can be converted only to another
 136    --  type conformant remote access-to-subprogram type. Secondly, a value
 137    --  of a remote access-to-class-wide type can be converted only to another
 138    --  remote access-to-class-wide type (RM E.2.3(17,20)).
 139
 140    procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id);
 141    --  Check validity of declaration if shared passive unit. It should not
 142    --  contain the declaration of an access-to-object type whose designated
 143    --  type is a class-wide type ,task type or protected type. E.2.1(7).
 144    --  T is the entity of the declared type.
 145
 146    procedure Validate_Static_Object_Name (N : Node_Id);
 147    --  In the elaboration code of a preelaborated library unit, check
 148    --  that we do not have the evaluation of a primary that is a name of
 149    --  an object, unless the name is a static expression (RM 10.2.1(8)).
 150    --  Non-static constant and variable are the targets, generic parameters
 151    --  are not included because the generic declaration and body are
 152    --  preelaborable.
 153
 154    procedure Validate_RACW_Primitives (T : Entity_Id);
 155    --  Enforce constraints on primitive operations of the designated type of
 156    --  an RACW. Note that since the complete set of primitive operations of the
 157    --  designated type needs to be known, we must defer these checks until the
 158    --  designated type is frozen.
 159
 160 end Sem_Cat;