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 --                                                                          --
  10 --          Copyright (C) 1992-2000 Free Software Foundation, Inc.          --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- GNAT was originally developed  by the GNAT team at  New York University. --
  24 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  25 --                                                                          --
  26 ------------------------------------------------------------------------------
  27
  28 --  This unit contains the routines used for checking for conformance with
  29 --  the semantic restrictions required for the categorization pragmas:
  30 --
  31 --    Preelaborate
  32 --    Pure,
  33 --    Remote_Call_Interface
  34 --    Remote_Types
  35 --    Shared_Passive
  36 --
  37 --  Note that we treat Preelaborate as a categorization pragma, even though
  38 --  strictly, according to RM E.2(2,3), the term does not apply in this case.
  39
  40 with Types; use Types;
  41
  42 package Sem_Cat is
  43
  44    function In_Preelaborated_Unit return Boolean;
  45    --  Determines if the current scope is within a preelaborated compilation
  46    --  unit, that is one to which one of the pragmas Preelaborate, Pure,
  47    --  Shared_Passive, Remote_Types, or inside a unit other than a package
  48    --  body with pragma Remote_Call_Interface.
  49
  50    function In_Pure_Unit return Boolean;
  51    pragma Inline (In_Pure_Unit);
  52    --  Determines if the current scope is within pure compilation unit,
  53    --  that is, one to which the pragmas Pure is applied.
  54
  55    function In_Subprogram_Task_Protected_Unit return Boolean;
  56    --  Determines if the current scope is within a subprogram, task
  57    --  or protected unit. Used to validate if the library unit is Pure
  58    --  (RM 10.2.1(16)).
  59
  60    procedure Set_Categorization_From_Pragmas (N : Node_Id);
  61    --  Since validation of categorization dependency is done during analyze
  62    --  so categorization flags from following pragmas should be set before
  63    --  validation begin. N is the N_Compilation_Unit node.
  64
  65    procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id);
  66    --  Validate all constraints against declaration of access types in
  67    --  categorized library units. Usually this is a violation in Pure unit,
  68    --  Shared_Passive unit. N is the declaration node.
  69
  70    procedure Validate_Ancestor_Part (N : Node_Id);
  71    --  Checks that a type given as the ancestor in an extension aggregate
  72    --  satisfies the restriction of 10.2.1(9).
  73
  74    procedure Validate_Categorization_Dependency (N : Node_Id; E : Entity_Id);
  75    --  There are restrictions on lib unit that semantically depends on other
  76    --  units (RM E.2(5), 10.2.1(11). This procedure checks the restrictions
  77    --  on categorizations. N is the current unit node, and E is the current
  78    --  library unit entity.
  79
  80    procedure Validate_Controlled_Object (E : Entity_Id);
  81    --  Given an entity for a library level controlled object, check that it is
  82    --  not in a preelaborated unit (prohibited by RM 10.2.1(9)).
  83
  84    procedure Validate_Null_Statement_Sequence (N : Node_Id);
  85    --  Given N, a package body node, check that a handled statement sequence
  86    --  in a preelaborable body contains no statements other than labels or
  87    --  null statements, as required by RM 10.2.1(6).
  88
  89    procedure Validate_Object_Declaration (N : Node_Id);
  90    --  Given N, an object declaration node, validates all the constraints in
  91    --  a preelaborable library unit, including creation of task objects etc.
  92    --  Note that this is called when the corresponding object is frozen since
  93    --  the checks cannot be made before knowing if the object is imported.
  94
  95    procedure Validate_RCI_Declarations (P : Entity_Id);
  96    --  Apply semantic checks given in  E2.3(10-14).
  97
  98    procedure Validate_RCI_Subprogram_Declaration (N : Node_Id);
  99    --  Check for RCI unit subprogram declarations with respect to
 100    --  in-lined subprogram and subprogram with access parameter or
 101    --  limited type parameter without Read and Write.
 102
 103    procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id);
 104    --  Checks that Storage_Pool and Storage_Size attribute references are
 105    --  not applied to remote access-to-class-wide types. And the expected
 106    --  type for an allocator shall not be a remote access-to-class-wide
 107    --  type. And a remote access-to-class-wide type shall not be an actual
 108    --  parameter for a generic formal access type. RM E.2.3(22).
 109
 110    procedure Validate_Remote_Access_To_Subprogram_Type (N : Node_Id);
 111    --  Checks that a remote access to subprogram type does not have a
 112    --  parameter of an access type. This is not strictly forbidden at this
 113    --  time, but this is useless, as such a RAS type will not be usable
 114    --  per E.2.2(12) and E.2.3(14).
 115
 116    procedure Validate_RT_RAT_Component (N : Node_Id);
 117    --  Given N, the package library unit declaration node, we should check
 118    --  against RM:9.95 E.2.2(8): the full view of a type declared in the
 119    --  visible part of a Remote Types unit has a part that is of a non-remote
 120    --  access type which has no read/write.
 121
 122    procedure Validate_Remote_Type_Type_Conversion (N : Node_Id);
 123    --  Check for remote-type type conversion constraints. First, a value of
 124    --  a remote access-to-subprogram type can be converted only to another
 125    --  type conformant remote access-to-subprogram type. Secondly, a value
 126    --  of a remote access-to-class-wide type can be converted only to another
 127    --  remote access-to-class-wide type (RM E.2.3(17,20)).
 128
 129    procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id);
 130    --  Check validity of declaration if shared passive unit. It should not
 131    --  contain the declaration of an access-to-object type whose designated
 132    --  type is a class-wide type ,task type or protected type. E.2.1(7).
 133    --  T is the entity of the declared type.
 134
 135    procedure Validate_Static_Object_Name (N : Node_Id);
 136    --  In the elaboration code of a preelaborated library unit, check
 137    --  that we do not have the evaluation of a primary that is a name of
 138    --  an object, unless the name is a static expression (RM 10.2.1(8)).
 139    --  Non-static constant and variable are the targets, generic parameters
 140    --  are not included because the generic declaration and body are
 141    --  preelaborable.
 142
 143 end Sem_Cat;