1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
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. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Disp; use Exp_Disp;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
43 with Rtsfind; use Rtsfind;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Ch3; use Sem_Ch3;
47 with Sem_Ch6; use Sem_Ch6;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Res; use Sem_Res;
51 with Sem_Type; use Sem_Type;
52 with Sem_Util; use Sem_Util;
53 with Sem_Warn; use Sem_Warn;
54 with Sinput; use Sinput;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Stringt; use Stringt;
59 with Targparm; use Targparm;
60 with Ttypes; use Ttypes;
61 with Tbuild; use Tbuild;
62 with Urealp; use Urealp;
64 with GNAT.Heap_Sort_G;
66 package body Sem_Ch13 is
68 SSU : constant Pos := System_Storage_Unit;
69 -- Convenient short hand for commonly used constant
71 -----------------------
72 -- Local Subprograms --
73 -----------------------
75 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id);
76 -- This routine is called after setting the Esize of type entity Typ.
77 -- The purpose is to deal with the situation where an alignment has been
78 -- inherited from a derived type that is no longer appropriate for the
79 -- new Esize value. In this case, we reset the Alignment to unknown.
81 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
82 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
83 -- then either there are pragma Invariant entries on the rep chain for the
84 -- type (note that Predicate aspects are converted to pragma Predicate), or
85 -- there are inherited aspects from a parent type, or ancestor subtypes.
86 -- This procedure builds the spec and body for the Predicate function that
87 -- tests these predicates. N is the freeze node for the type. The spec of
88 -- the function is inserted before the freeze node, and the body of the
89 -- function is inserted after the freeze node.
91 procedure Build_Static_Predicate
95 -- Given a predicated type Typ, where Typ is a discrete static subtype,
96 -- whose predicate expression is Expr, tests if Expr is a static predicate,
97 -- and if so, builds the predicate range list. Nam is the name of the one
98 -- argument to the predicate function. Occurrences of the type name in the
99 -- predicate expression have been replaced by identifier references to this
100 -- name, which is unique, so any identifier with Chars matching Nam must be
101 -- a reference to the type. If the predicate is non-static, this procedure
102 -- returns doing nothing. If the predicate is static, then the predicate
103 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
104 -- a canonicalized membership operation.
106 function Get_Alignment_Value (Expr : Node_Id) return Uint;
107 -- Given the expression for an alignment value, returns the corresponding
108 -- Uint value. If the value is inappropriate, then error messages are
109 -- posted as required, and a value of No_Uint is returned.
111 function Is_Operational_Item (N : Node_Id) return Boolean;
112 -- A specification for a stream attribute is allowed before the full type
113 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
114 -- that do not specify a representation characteristic are operational
117 procedure New_Stream_Subprogram
121 Nam : TSS_Name_Type);
122 -- Create a subprogram renaming of a given stream attribute to the
123 -- designated subprogram and then in the tagged case, provide this as a
124 -- primitive operation, or in the non-tagged case make an appropriate TSS
125 -- entry. This is more properly an expansion activity than just semantics,
126 -- but the presence of user-defined stream functions for limited types is a
127 -- legality check, which is why this takes place here rather than in
128 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
129 -- function to be generated.
131 -- To avoid elaboration anomalies with freeze nodes, for untagged types
132 -- we generate both a subprogram declaration and a subprogram renaming
133 -- declaration, so that the attribute specification is handled as a
134 -- renaming_as_body. For tagged types, the specification is one of the
138 with procedure Replace_Type_Reference (N : Node_Id);
139 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
140 -- This is used to scan an expression for a predicate or invariant aspect
141 -- replacing occurrences of the name TName (the name of the subtype to
142 -- which the aspect applies) with appropriate references to the parameter
143 -- of the predicate function or invariant procedure. The procedure passed
144 -- as a generic parameter does the actual replacement of node N, which is
145 -- either a simple direct reference to TName, or a selected component that
146 -- represents an appropriately qualified occurrence of TName.
152 Biased : Boolean := True);
153 -- If Biased is True, sets Has_Biased_Representation flag for E, and
154 -- outputs a warning message at node N if Warn_On_Biased_Representation is
155 -- is True. This warning inserts the string Msg to describe the construct
158 ----------------------------------------------
159 -- Table for Validate_Unchecked_Conversions --
160 ----------------------------------------------
162 -- The following table collects unchecked conversions for validation.
163 -- Entries are made by Validate_Unchecked_Conversion and then the
164 -- call to Validate_Unchecked_Conversions does the actual error
165 -- checking and posting of warnings. The reason for this delayed
166 -- processing is to take advantage of back-annotations of size and
167 -- alignment values performed by the back end.
169 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
170 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
171 -- will already have modified all Sloc values if the -gnatD option is set.
173 type UC_Entry is record
174 Eloc : Source_Ptr; -- node used for posting warnings
175 Source : Entity_Id; -- source type for unchecked conversion
176 Target : Entity_Id; -- target type for unchecked conversion
179 package Unchecked_Conversions is new Table.Table (
180 Table_Component_Type => UC_Entry,
181 Table_Index_Type => Int,
182 Table_Low_Bound => 1,
184 Table_Increment => 200,
185 Table_Name => "Unchecked_Conversions");
187 ----------------------------------------
188 -- Table for Validate_Address_Clauses --
189 ----------------------------------------
191 -- If an address clause has the form
193 -- for X'Address use Expr
195 -- where Expr is of the form Y'Address or recursively is a reference
196 -- to a constant of either of these forms, and X and Y are entities of
197 -- objects, then if Y has a smaller alignment than X, that merits a
198 -- warning about possible bad alignment. The following table collects
199 -- address clauses of this kind. We put these in a table so that they
200 -- can be checked after the back end has completed annotation of the
201 -- alignments of objects, since we can catch more cases that way.
203 type Address_Clause_Check_Record is record
205 -- The address clause
208 -- The entity of the object overlaying Y
211 -- The entity of the object being overlaid
214 -- Whether the address is offset within Y
217 package Address_Clause_Checks is new Table.Table (
218 Table_Component_Type => Address_Clause_Check_Record,
219 Table_Index_Type => Int,
220 Table_Low_Bound => 1,
222 Table_Increment => 200,
223 Table_Name => "Address_Clause_Checks");
225 -----------------------------------------
226 -- Adjust_Record_For_Reverse_Bit_Order --
227 -----------------------------------------
229 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
234 -- Processing depends on version of Ada
236 -- For Ada 95, we just renumber bits within a storage unit. We do the
237 -- same for Ada 83 mode, since we recognize pragma Bit_Order in Ada 83,
238 -- and are free to add this extension.
240 if Ada_Version < Ada_2005 then
241 Comp := First_Component_Or_Discriminant (R);
242 while Present (Comp) loop
243 CC := Component_Clause (Comp);
245 -- If component clause is present, then deal with the non-default
246 -- bit order case for Ada 95 mode.
248 -- We only do this processing for the base type, and in fact that
249 -- is important, since otherwise if there are record subtypes, we
250 -- could reverse the bits once for each subtype, which is wrong.
253 and then Ekind (R) = E_Record_Type
256 CFB : constant Uint := Component_Bit_Offset (Comp);
257 CSZ : constant Uint := Esize (Comp);
258 CLC : constant Node_Id := Component_Clause (Comp);
259 Pos : constant Node_Id := Position (CLC);
260 FB : constant Node_Id := First_Bit (CLC);
262 Storage_Unit_Offset : constant Uint :=
263 CFB / System_Storage_Unit;
265 Start_Bit : constant Uint :=
266 CFB mod System_Storage_Unit;
269 -- Cases where field goes over storage unit boundary
271 if Start_Bit + CSZ > System_Storage_Unit then
273 -- Allow multi-byte field but generate warning
275 if Start_Bit mod System_Storage_Unit = 0
276 and then CSZ mod System_Storage_Unit = 0
279 ("multi-byte field specified with non-standard"
280 & " Bit_Order?", CLC);
282 if Bytes_Big_Endian then
284 ("bytes are not reversed "
285 & "(component is big-endian)?", CLC);
288 ("bytes are not reversed "
289 & "(component is little-endian)?", CLC);
292 -- Do not allow non-contiguous field
296 ("attempt to specify non-contiguous field "
297 & "not permitted", CLC);
299 ("\caused by non-standard Bit_Order "
302 ("\consider possibility of using "
303 & "Ada 2005 mode here", CLC);
306 -- Case where field fits in one storage unit
309 -- Give warning if suspicious component clause
311 if Intval (FB) >= System_Storage_Unit
312 and then Warn_On_Reverse_Bit_Order
315 ("?Bit_Order clause does not affect " &
316 "byte ordering", Pos);
318 Intval (Pos) + Intval (FB) /
321 ("?position normalized to ^ before bit " &
322 "order interpreted", Pos);
325 -- Here is where we fix up the Component_Bit_Offset value
326 -- to account for the reverse bit order. Some examples of
327 -- what needs to be done are:
329 -- First_Bit .. Last_Bit Component_Bit_Offset
341 -- The rule is that the first bit is is obtained by
342 -- subtracting the old ending bit from storage_unit - 1.
344 Set_Component_Bit_Offset
346 (Storage_Unit_Offset * System_Storage_Unit) +
347 (System_Storage_Unit - 1) -
348 (Start_Bit + CSZ - 1));
350 Set_Normalized_First_Bit
352 Component_Bit_Offset (Comp) mod
353 System_Storage_Unit);
358 Next_Component_Or_Discriminant (Comp);
361 -- For Ada 2005, we do machine scalar processing, as fully described In
362 -- AI-133. This involves gathering all components which start at the
363 -- same byte offset and processing them together. Same approach is still
364 -- valid in later versions including Ada 2012.
368 Max_Machine_Scalar_Size : constant Uint :=
370 (Standard_Long_Long_Integer_Size);
371 -- We use this as the maximum machine scalar size
374 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
377 -- This first loop through components does two things. First it
378 -- deals with the case of components with component clauses whose
379 -- length is greater than the maximum machine scalar size (either
380 -- accepting them or rejecting as needed). Second, it counts the
381 -- number of components with component clauses whose length does
382 -- not exceed this maximum for later processing.
385 Comp := First_Component_Or_Discriminant (R);
386 while Present (Comp) loop
387 CC := Component_Clause (Comp);
391 Fbit : constant Uint :=
392 Static_Integer (First_Bit (CC));
393 Lbit : constant Uint :=
394 Static_Integer (Last_Bit (CC));
397 -- Case of component with last bit >= max machine scalar
399 if Lbit >= Max_Machine_Scalar_Size then
401 -- This is allowed only if first bit is zero, and
402 -- last bit + 1 is a multiple of storage unit size.
404 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
406 -- This is the case to give a warning if enabled
408 if Warn_On_Reverse_Bit_Order then
410 ("multi-byte field specified with "
411 & " non-standard Bit_Order?", CC);
413 if Bytes_Big_Endian then
415 ("\bytes are not reversed "
416 & "(component is big-endian)?", CC);
419 ("\bytes are not reversed "
420 & "(component is little-endian)?", CC);
424 -- Give error message for RM 13.4.1(10) violation
428 ("machine scalar rules not followed for&",
429 First_Bit (CC), Comp);
431 Error_Msg_Uint_1 := Lbit;
432 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
434 ("\last bit (^) exceeds maximum machine "
438 if (Lbit + 1) mod SSU /= 0 then
439 Error_Msg_Uint_1 := SSU;
441 ("\and is not a multiple of Storage_Unit (^) "
442 & "('R'M 13.4.1(10))",
446 Error_Msg_Uint_1 := Fbit;
448 ("\and first bit (^) is non-zero "
449 & "('R'M 13.4.1(10))",
454 -- OK case of machine scalar related component clause,
455 -- For now, just count them.
458 Num_CC := Num_CC + 1;
463 Next_Component_Or_Discriminant (Comp);
466 -- We need to sort the component clauses on the basis of the
467 -- Position values in the clause, so we can group clauses with
468 -- the same Position. together to determine the relevant machine
472 Comps : array (0 .. Num_CC) of Entity_Id;
473 -- Array to collect component and discriminant entities. The
474 -- data starts at index 1, the 0'th entry is for the sort
477 function CP_Lt (Op1, Op2 : Natural) return Boolean;
478 -- Compare routine for Sort
480 procedure CP_Move (From : Natural; To : Natural);
481 -- Move routine for Sort
483 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
487 -- Start and stop positions in the component list of the set of
488 -- components with the same starting position (that constitute
489 -- components in a single machine scalar).
492 -- Maximum last bit value of any component in this set
495 -- Corresponding machine scalar size
501 function CP_Lt (Op1, Op2 : Natural) return Boolean is
503 return Position (Component_Clause (Comps (Op1))) <
504 Position (Component_Clause (Comps (Op2)));
511 procedure CP_Move (From : Natural; To : Natural) is
513 Comps (To) := Comps (From);
516 -- Start of processing for Sort_CC
519 -- Collect the machine scalar relevant component clauses
522 Comp := First_Component_Or_Discriminant (R);
523 while Present (Comp) loop
525 CC : constant Node_Id := Component_Clause (Comp);
528 -- Collect only component clauses whose last bit is less
529 -- than machine scalar size. Any component clause whose
530 -- last bit exceeds this value does not take part in
531 -- machine scalar layout considerations. The test for
532 -- Error_Posted makes sure we exclude component clauses
533 -- for which we already posted an error.
536 and then not Error_Posted (Last_Bit (CC))
537 and then Static_Integer (Last_Bit (CC)) <
538 Max_Machine_Scalar_Size
540 Num_CC := Num_CC + 1;
541 Comps (Num_CC) := Comp;
545 Next_Component_Or_Discriminant (Comp);
548 -- Sort by ascending position number
550 Sorting.Sort (Num_CC);
552 -- We now have all the components whose size does not exceed
553 -- the max machine scalar value, sorted by starting position.
554 -- In this loop we gather groups of clauses starting at the
555 -- same position, to process them in accordance with AI-133.
558 while Stop < Num_CC loop
563 (Last_Bit (Component_Clause (Comps (Start))));
564 while Stop < Num_CC loop
566 (Position (Component_Clause (Comps (Stop + 1)))) =
568 (Position (Component_Clause (Comps (Stop))))
576 (Component_Clause (Comps (Stop)))));
582 -- Now we have a group of component clauses from Start to
583 -- Stop whose positions are identical, and MaxL is the
584 -- maximum last bit value of any of these components.
586 -- We need to determine the corresponding machine scalar
587 -- size. This loop assumes that machine scalar sizes are
588 -- even, and that each possible machine scalar has twice
589 -- as many bits as the next smaller one.
591 MSS := Max_Machine_Scalar_Size;
593 and then (MSS / 2) >= SSU
594 and then (MSS / 2) > MaxL
599 -- Here is where we fix up the Component_Bit_Offset value
600 -- to account for the reverse bit order. Some examples of
601 -- what needs to be done for the case of a machine scalar
604 -- First_Bit .. Last_Bit Component_Bit_Offset
616 -- The rule is that the first bit is obtained by subtracting
617 -- the old ending bit from machine scalar size - 1.
619 for C in Start .. Stop loop
621 Comp : constant Entity_Id := Comps (C);
622 CC : constant Node_Id :=
623 Component_Clause (Comp);
624 LB : constant Uint :=
625 Static_Integer (Last_Bit (CC));
626 NFB : constant Uint := MSS - Uint_1 - LB;
627 NLB : constant Uint := NFB + Esize (Comp) - 1;
628 Pos : constant Uint :=
629 Static_Integer (Position (CC));
632 if Warn_On_Reverse_Bit_Order then
633 Error_Msg_Uint_1 := MSS;
635 ("info: reverse bit order in machine " &
636 "scalar of length^?", First_Bit (CC));
637 Error_Msg_Uint_1 := NFB;
638 Error_Msg_Uint_2 := NLB;
640 if Bytes_Big_Endian then
642 ("?\info: big-endian range for "
643 & "component & is ^ .. ^",
644 First_Bit (CC), Comp);
647 ("?\info: little-endian range "
648 & "for component & is ^ .. ^",
649 First_Bit (CC), Comp);
653 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
654 Set_Normalized_First_Bit (Comp, NFB mod SSU);
661 end Adjust_Record_For_Reverse_Bit_Order;
663 --------------------------------------
664 -- Alignment_Check_For_Esize_Change --
665 --------------------------------------
667 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id) is
669 -- If the alignment is known, and not set by a rep clause, and is
670 -- inconsistent with the size being set, then reset it to unknown,
671 -- we assume in this case that the size overrides the inherited
672 -- alignment, and that the alignment must be recomputed.
674 if Known_Alignment (Typ)
675 and then not Has_Alignment_Clause (Typ)
676 and then Esize (Typ) mod (Alignment (Typ) * SSU) /= 0
678 Init_Alignment (Typ);
680 end Alignment_Check_For_Esize_Change;
682 -----------------------------------
683 -- Analyze_Aspect_Specifications --
684 -----------------------------------
686 procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is
691 L : constant List_Id := Aspect_Specifications (N);
693 Ins_Node : Node_Id := N;
694 -- Insert pragmas (except Pre/Post/Invariant/Predicate) after this node
696 -- The general processing involves building an attribute definition
697 -- clause or a pragma node that corresponds to the access type. Then
698 -- one of two things happens:
700 -- If we are required to delay the evaluation of this aspect to the
701 -- freeze point, we attach the corresponding pragma/attribute definition
702 -- clause to the aspect specification node, which is then placed in the
703 -- Rep Item chain. In this case we mark the entity by setting the flag
704 -- Has_Delayed_Aspects and we evaluate the rep item at the freeze point.
706 -- If no delay is required, we just insert the pragma or attribute
707 -- after the declaration, and it will get processed by the normal
708 -- circuit. The From_Aspect_Specification flag is set on the pragma
709 -- or attribute definition node in either case to activate special
710 -- processing (e.g. not traversing the list of homonyms for inline).
712 Delay_Required : Boolean;
713 -- Set True if delay is required
716 pragma Assert (Present (L));
718 -- Loop through aspects
721 Aspect_Loop : while Present (Aspect) loop
723 Loc : constant Source_Ptr := Sloc (Aspect);
724 Id : constant Node_Id := Identifier (Aspect);
725 Expr : constant Node_Id := Expression (Aspect);
726 Nam : constant Name_Id := Chars (Id);
727 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
730 Eloc : Source_Ptr := Sloc (Expr);
731 -- Source location of expression, modified when we split PPC's
733 procedure Check_False_Aspect_For_Derived_Type;
734 -- This procedure checks for the case of a false aspect for a
735 -- derived type, which improperly tries to cancel an aspect
736 -- inherited from the parent;
738 -----------------------------------------
739 -- Check_False_Aspect_For_Derived_Type --
740 -----------------------------------------
742 procedure Check_False_Aspect_For_Derived_Type is
744 -- We are only checking derived types
746 if not Is_Derived_Type (E) then
751 when Aspect_Atomic | Aspect_Shared =>
752 if not Is_Atomic (E) then
756 when Aspect_Atomic_Components =>
757 if not Has_Atomic_Components (E) then
761 when Aspect_Discard_Names =>
762 if not Discard_Names (E) then
767 if not Is_Packed (E) then
771 when Aspect_Unchecked_Union =>
772 if not Is_Unchecked_Union (E) then
776 when Aspect_Volatile =>
777 if not Is_Volatile (E) then
781 when Aspect_Volatile_Components =>
782 if not Has_Volatile_Components (E) then
790 -- Fall through means we are canceling an inherited aspect
792 Error_Msg_Name_1 := Nam;
794 ("derived type& inherits aspect%, cannot cancel", Expr, E);
795 end Check_False_Aspect_For_Derived_Type;
797 -- Start of processing for Aspect_Loop
800 -- Skip aspect if already analyzed (not clear if this is needed)
802 if Analyzed (Aspect) then
806 Set_Analyzed (Aspect);
807 Set_Entity (Aspect, E);
808 Ent := New_Occurrence_Of (E, Sloc (Id));
810 -- Check for duplicate aspect. Note that the Comes_From_Source
811 -- test allows duplicate Pre/Post's that we generate internally
812 -- to escape being flagged here.
815 while Anod /= Aspect loop
816 if Same_Aspect (A_Id, Get_Aspect_Id (Chars (Identifier (Anod))))
817 and then Comes_From_Source (Aspect)
819 Error_Msg_Name_1 := Nam;
820 Error_Msg_Sloc := Sloc (Anod);
822 -- Case of same aspect specified twice
824 if Class_Present (Anod) = Class_Present (Aspect) then
825 if not Class_Present (Anod) then
827 ("aspect% for & previously given#",
831 ("aspect `%''Class` for & previously given#",
835 -- Case of Pre and Pre'Class both specified
837 elsif Nam = Name_Pre then
838 if Class_Present (Aspect) then
840 ("aspect `Pre''Class` for & is not allowed here",
843 ("\since aspect `Pre` previously given#",
848 ("aspect `Pre` for & is not allowed here",
851 ("\since aspect `Pre''Class` previously given#",
862 -- Copy expression for later processing by the procedures
863 -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations]
865 Set_Entity (Id, New_Copy_Tree (Expr));
867 -- Processing based on specific aspect
871 -- No_Aspect should be impossible
876 -- Aspects taking an optional boolean argument. For all of
877 -- these we just create a matching pragma and insert it, if
878 -- the expression is missing or set to True. If the expression
879 -- is False, we can ignore the aspect with the exception that
880 -- in the case of a derived type, we must check for an illegal
881 -- attempt to cancel an inherited aspect.
883 when Boolean_Aspects =>
884 Set_Is_Boolean_Aspect (Aspect);
887 and then Is_False (Static_Boolean (Expr))
889 Check_False_Aspect_For_Derived_Type;
893 -- If True, build corresponding pragma node
897 Pragma_Argument_Associations => New_List (Ent),
899 Make_Identifier (Sloc (Id), Chars (Id)));
901 -- Never need to delay for boolean aspects
903 Delay_Required := False;
905 -- Library unit aspects. These are boolean aspects, but we
906 -- have to do special things with the insertion, since the
907 -- pragma belongs inside the declarations of a package.
909 when Library_Unit_Aspects =>
911 and then Is_False (Static_Boolean (Expr))
916 -- Build corresponding pragma node
920 Pragma_Argument_Associations => New_List (Ent),
922 Make_Identifier (Sloc (Id), Chars (Id)));
924 -- This requires special handling in the case of a package
925 -- declaration, the pragma needs to be inserted in the list
926 -- of declarations for the associated package. There is no
927 -- issue of visibility delay for these aspects.
929 if Nkind (N) = N_Package_Declaration then
930 if Nkind (Parent (N)) /= N_Compilation_Unit then
932 ("incorrect context for library unit aspect&", Id);
935 (Aitem, Visible_Declarations (Specification (N)));
941 -- If not package declaration, no delay is required
943 Delay_Required := False;
945 -- Aspects corresponding to attribute definition clauses
947 when Aspect_Address |
950 Aspect_Component_Size |
951 Aspect_External_Tag |
953 Aspect_Machine_Radix |
958 Aspect_Storage_Pool |
959 Aspect_Storage_Size |
964 -- Construct the attribute definition clause
967 Make_Attribute_Definition_Clause (Loc,
970 Expression => Relocate_Node (Expr));
972 -- A delay is required except in the common case where
973 -- the expression is a literal, in which case it is fine
974 -- to take care of it right away.
976 if Nkind_In (Expr, N_Integer_Literal, N_String_Literal) then
977 Delay_Required := False;
979 Delay_Required := True;
980 Set_Is_Delayed_Aspect (Aspect);
983 -- Aspects corresponding to pragmas with two arguments, where
984 -- the first argument is a local name referring to the entity,
985 -- and the second argument is the aspect definition expression
986 -- which is an expression which must be delayed and analyzed.
988 when Aspect_Default_Component_Value |
989 Aspect_Default_Value =>
991 -- Construct the pragma
995 Pragma_Argument_Associations => New_List (
996 New_Occurrence_Of (E, Loc),
997 Relocate_Node (Expr)),
999 Make_Identifier (Sloc (Id), Chars (Id)));
1001 -- These aspects do require delaying
1003 Delay_Required := True;
1004 Set_Is_Delayed_Aspect (Aspect);
1006 -- Aspects corresponding to pragmas with two arguments, where
1007 -- the first argument is a local name referring to the entity,
1008 -- and the second argument is the aspect definition expression
1009 -- which is an expression that does not get analyzed.
1011 when Aspect_Suppress |
1012 Aspect_Unsuppress =>
1014 -- Construct the pragma
1018 Pragma_Argument_Associations => New_List (
1019 New_Occurrence_Of (E, Loc),
1020 Relocate_Node (Expr)),
1021 Pragma_Identifier =>
1022 Make_Identifier (Sloc (Id), Chars (Id)));
1024 -- We don't have to play the delay game here, since the only
1025 -- values are check names which don't get analyzed anyway.
1027 Delay_Required := False;
1029 -- Aspects corresponding to pragmas with two arguments, where
1030 -- the second argument is a local name referring to the entity,
1031 -- and the first argument is the aspect definition expression.
1033 when Aspect_Warnings =>
1035 -- Construct the pragma
1039 Pragma_Argument_Associations => New_List (
1040 Relocate_Node (Expr),
1041 New_Occurrence_Of (E, Loc)),
1042 Pragma_Identifier =>
1043 Make_Identifier (Sloc (Id), Chars (Id)),
1044 Class_Present => Class_Present (Aspect));
1046 -- We don't have to play the delay game here, since the only
1047 -- values are ON/OFF which don't get analyzed anyway.
1049 Delay_Required := False;
1051 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
1052 -- with a first argument that is the expression, and a second
1053 -- argument that is an informative message if the test fails.
1054 -- This is inserted right after the declaration, to get the
1055 -- required pragma placement. The processing for the pragmas
1056 -- takes care of the required delay.
1058 when Pre_Post_Aspects => declare
1062 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
1063 Pname := Name_Precondition;
1065 Pname := Name_Postcondition;
1068 -- If the expressions is of the form A and then B, then
1069 -- we generate separate Pre/Post aspects for the separate
1070 -- clauses. Since we allow multiple pragmas, there is no
1071 -- problem in allowing multiple Pre/Post aspects internally.
1073 -- We do not do this for Pre'Class, since we have to put
1074 -- these conditions together in a complex OR expression
1076 if Pname = Name_Postcondition
1077 or else not Class_Present (Aspect)
1079 while Nkind (Expr) = N_And_Then loop
1080 Insert_After (Aspect,
1081 Make_Aspect_Specification (Sloc (Right_Opnd (Expr)),
1082 Identifier => Identifier (Aspect),
1083 Expression => Relocate_Node (Right_Opnd (Expr)),
1084 Class_Present => Class_Present (Aspect),
1085 Split_PPC => True));
1086 Rewrite (Expr, Relocate_Node (Left_Opnd (Expr)));
1087 Eloc := Sloc (Expr);
1091 -- Build the precondition/postcondition pragma
1095 Pragma_Identifier =>
1096 Make_Identifier (Sloc (Id), Pname),
1097 Class_Present => Class_Present (Aspect),
1098 Split_PPC => Split_PPC (Aspect),
1099 Pragma_Argument_Associations => New_List (
1100 Make_Pragma_Argument_Association (Eloc,
1101 Chars => Name_Check,
1102 Expression => Relocate_Node (Expr))));
1104 -- Add message unless exception messages are suppressed
1106 if not Opt.Exception_Locations_Suppressed then
1107 Append_To (Pragma_Argument_Associations (Aitem),
1108 Make_Pragma_Argument_Association (Eloc,
1109 Chars => Name_Message,
1111 Make_String_Literal (Eloc,
1113 & Get_Name_String (Pname)
1115 & Build_Location_String (Eloc))));
1118 Set_From_Aspect_Specification (Aitem, True);
1119 Set_Is_Delayed_Aspect (Aspect);
1121 -- For Pre/Post cases, insert immediately after the entity
1122 -- declaration, since that is the required pragma placement.
1123 -- Note that for these aspects, we do not have to worry
1124 -- about delay issues, since the pragmas themselves deal
1125 -- with delay of visibility for the expression analysis.
1127 -- If the entity is a library-level subprogram, the pre/
1128 -- postconditions must be treated as late pragmas.
1130 if Nkind (Parent (N)) = N_Compilation_Unit then
1131 Add_Global_Declaration (Aitem);
1133 Insert_After (N, Aitem);
1139 -- Invariant aspects generate a corresponding pragma with a
1140 -- first argument that is the entity, a second argument that is
1141 -- the expression and a third argument that is an appropriate
1142 -- message. This is inserted right after the declaration, to
1143 -- get the required pragma placement. The pragma processing
1144 -- takes care of the required delay.
1146 when Aspect_Invariant |
1147 Aspect_Type_Invariant =>
1149 -- Construct the pragma
1153 Pragma_Argument_Associations =>
1154 New_List (Ent, Relocate_Node (Expr)),
1155 Class_Present => Class_Present (Aspect),
1156 Pragma_Identifier =>
1157 Make_Identifier (Sloc (Id), Name_Invariant));
1159 -- Add message unless exception messages are suppressed
1161 if not Opt.Exception_Locations_Suppressed then
1162 Append_To (Pragma_Argument_Associations (Aitem),
1163 Make_Pragma_Argument_Association (Eloc,
1164 Chars => Name_Message,
1166 Make_String_Literal (Eloc,
1167 Strval => "failed invariant from "
1168 & Build_Location_String (Eloc))));
1171 Set_From_Aspect_Specification (Aitem, True);
1172 Set_Is_Delayed_Aspect (Aspect);
1174 -- For Invariant case, insert immediately after the entity
1175 -- declaration. We do not have to worry about delay issues
1176 -- since the pragma processing takes care of this.
1178 Insert_After (N, Aitem);
1181 -- Predicate aspects generate a corresponding pragma with a
1182 -- first argument that is the entity, and the second argument
1183 -- is the expression.
1185 when Aspect_Dynamic_Predicate |
1187 Aspect_Static_Predicate =>
1189 -- Construct the pragma (always a pragma Predicate, with
1190 -- flags recording whether
1194 Pragma_Argument_Associations =>
1195 New_List (Ent, Relocate_Node (Expr)),
1196 Class_Present => Class_Present (Aspect),
1197 Pragma_Identifier =>
1198 Make_Identifier (Sloc (Id), Name_Predicate));
1200 Set_From_Aspect_Specification (Aitem, True);
1202 -- Set special flags for dynamic/static cases
1204 if A_Id = Aspect_Dynamic_Predicate then
1205 Set_From_Dynamic_Predicate (Aitem);
1206 elsif A_Id = Aspect_Static_Predicate then
1207 Set_From_Static_Predicate (Aitem);
1210 -- Make sure we have a freeze node (it might otherwise be
1211 -- missing in cases like subtype X is Y, and we would not
1212 -- have a place to build the predicate function).
1214 Set_Has_Predicates (E);
1215 Ensure_Freeze_Node (E);
1216 Set_Is_Delayed_Aspect (Aspect);
1217 Delay_Required := True;
1220 Set_From_Aspect_Specification (Aitem, True);
1222 -- If a delay is required, we delay the freeze (not much point in
1223 -- delaying the aspect if we don't delay the freeze!). The pragma
1224 -- or clause is then attached to the aspect specification which
1225 -- is placed in the rep item list.
1227 if Delay_Required then
1228 Ensure_Freeze_Node (E);
1229 Set_Is_Delayed_Aspect (Aitem);
1230 Set_Has_Delayed_Aspects (E);
1231 Set_Aspect_Rep_Item (Aspect, Aitem);
1232 Record_Rep_Item (E, Aspect);
1234 -- If no delay required, insert the pragma/clause in the tree
1237 -- If this is a compilation unit, we will put the pragma in
1238 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1240 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1242 Aux : constant Node_Id :=
1243 Aux_Decls_Node (Parent (Ins_Node));
1246 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1248 if No (Pragmas_After (Aux)) then
1249 Set_Pragmas_After (Aux, Empty_List);
1252 -- For Pre_Post put at start of list, otherwise at end
1254 if A_Id in Pre_Post_Aspects then
1255 Prepend (Aitem, Pragmas_After (Aux));
1257 Append (Aitem, Pragmas_After (Aux));
1261 -- Here if not compilation unit case
1264 -- For Pre/Post cases, insert immediately after the entity
1265 -- declaration, since that is the required pragma placement.
1267 if A_Id in Pre_Post_Aspects then
1268 Insert_After (N, Aitem);
1270 -- For all other cases, insert in sequence
1273 Insert_After (Ins_Node, Aitem);
1282 end loop Aspect_Loop;
1283 end Analyze_Aspect_Specifications;
1285 -----------------------
1286 -- Analyze_At_Clause --
1287 -----------------------
1289 -- An at clause is replaced by the corresponding Address attribute
1290 -- definition clause that is the preferred approach in Ada 95.
1292 procedure Analyze_At_Clause (N : Node_Id) is
1293 CS : constant Boolean := Comes_From_Source (N);
1296 -- This is an obsolescent feature
1298 Check_Restriction (No_Obsolescent_Features, N);
1300 if Warn_On_Obsolescent_Feature then
1302 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1304 ("\use address attribute definition clause instead?", N);
1307 -- Rewrite as address clause
1310 Make_Attribute_Definition_Clause (Sloc (N),
1311 Name => Identifier (N),
1312 Chars => Name_Address,
1313 Expression => Expression (N)));
1315 -- We preserve Comes_From_Source, since logically the clause still
1316 -- comes from the source program even though it is changed in form.
1318 Set_Comes_From_Source (N, CS);
1320 -- Analyze rewritten clause
1322 Analyze_Attribute_Definition_Clause (N);
1323 end Analyze_At_Clause;
1325 -----------------------------------------
1326 -- Analyze_Attribute_Definition_Clause --
1327 -----------------------------------------
1329 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1330 Loc : constant Source_Ptr := Sloc (N);
1331 Nam : constant Node_Id := Name (N);
1332 Attr : constant Name_Id := Chars (N);
1333 Expr : constant Node_Id := Expression (N);
1334 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1338 FOnly : Boolean := False;
1339 -- Reset to True for subtype specific attribute (Alignment, Size)
1340 -- and for stream attributes, i.e. those cases where in the call
1341 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1342 -- rules are checked. Note that the case of stream attributes is not
1343 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1344 -- disallow Storage_Size for derived task types, but that is also
1345 -- clearly unintentional.
1347 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1348 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1349 -- definition clauses.
1351 function Duplicate_Clause return Boolean;
1352 -- This routine checks if the aspect for U_Ent being given by attribute
1353 -- definition clause N is for an aspect that has already been specified,
1354 -- and if so gives an error message. If there is a duplicate, True is
1355 -- returned, otherwise if there is no error, False is returned.
1357 -----------------------------------
1358 -- Analyze_Stream_TSS_Definition --
1359 -----------------------------------
1361 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1362 Subp : Entity_Id := Empty;
1367 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1369 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1370 -- Return true if the entity is a subprogram with an appropriate
1371 -- profile for the attribute being defined.
1373 ----------------------
1374 -- Has_Good_Profile --
1375 ----------------------
1377 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1379 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1380 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1381 (False => E_Procedure, True => E_Function);
1385 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1389 F := First_Formal (Subp);
1392 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1393 or else Designated_Type (Etype (F)) /=
1394 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1399 if not Is_Function then
1403 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1404 (False => E_In_Parameter,
1405 True => E_Out_Parameter);
1407 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1415 Typ := Etype (Subp);
1418 return Base_Type (Typ) = Base_Type (Ent)
1419 and then No (Next_Formal (F));
1420 end Has_Good_Profile;
1422 -- Start of processing for Analyze_Stream_TSS_Definition
1427 if not Is_Type (U_Ent) then
1428 Error_Msg_N ("local name must be a subtype", Nam);
1432 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1434 -- If Pnam is present, it can be either inherited from an ancestor
1435 -- type (in which case it is legal to redefine it for this type), or
1436 -- be a previous definition of the attribute for the same type (in
1437 -- which case it is illegal).
1439 -- In the first case, it will have been analyzed already, and we
1440 -- can check that its profile does not match the expected profile
1441 -- for a stream attribute of U_Ent. In the second case, either Pnam
1442 -- has been analyzed (and has the expected profile), or it has not
1443 -- been analyzed yet (case of a type that has not been frozen yet
1444 -- and for which the stream attribute has been set using Set_TSS).
1447 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1449 Error_Msg_Sloc := Sloc (Pnam);
1450 Error_Msg_Name_1 := Attr;
1451 Error_Msg_N ("% attribute already defined #", Nam);
1457 if Is_Entity_Name (Expr) then
1458 if not Is_Overloaded (Expr) then
1459 if Has_Good_Profile (Entity (Expr)) then
1460 Subp := Entity (Expr);
1464 Get_First_Interp (Expr, I, It);
1465 while Present (It.Nam) loop
1466 if Has_Good_Profile (It.Nam) then
1471 Get_Next_Interp (I, It);
1476 if Present (Subp) then
1477 if Is_Abstract_Subprogram (Subp) then
1478 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1482 Set_Entity (Expr, Subp);
1483 Set_Etype (Expr, Etype (Subp));
1485 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1488 Error_Msg_Name_1 := Attr;
1489 Error_Msg_N ("incorrect expression for% attribute", Expr);
1491 end Analyze_Stream_TSS_Definition;
1493 ----------------------
1494 -- Duplicate_Clause --
1495 ----------------------
1497 function Duplicate_Clause return Boolean is
1501 -- Nothing to do if this attribute definition clause comes from
1502 -- an aspect specification, since we could not be duplicating an
1503 -- explicit clause, and we dealt with the case of duplicated aspects
1504 -- in Analyze_Aspect_Specifications.
1506 if From_Aspect_Specification (N) then
1510 -- Otherwise current clause may duplicate previous clause or a
1511 -- previously given aspect specification for the same aspect.
1513 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
1516 if Entity (A) = U_Ent then
1517 Error_Msg_Name_1 := Chars (N);
1518 Error_Msg_Sloc := Sloc (A);
1519 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
1525 end Duplicate_Clause;
1527 -- Start of processing for Analyze_Attribute_Definition_Clause
1530 -- Process Ignore_Rep_Clauses option
1532 if Ignore_Rep_Clauses then
1535 -- The following should be ignored. They do not affect legality
1536 -- and may be target dependent. The basic idea of -gnatI is to
1537 -- ignore any rep clauses that may be target dependent but do not
1538 -- affect legality (except possibly to be rejected because they
1539 -- are incompatible with the compilation target).
1541 when Attribute_Alignment |
1542 Attribute_Bit_Order |
1543 Attribute_Component_Size |
1544 Attribute_Machine_Radix |
1545 Attribute_Object_Size |
1548 Attribute_Stream_Size |
1549 Attribute_Value_Size =>
1551 Rewrite (N, Make_Null_Statement (Sloc (N)));
1554 -- The following should not be ignored, because in the first place
1555 -- they are reasonably portable, and should not cause problems in
1556 -- compiling code from another target, and also they do affect
1557 -- legality, e.g. failing to provide a stream attribute for a
1558 -- type may make a program illegal.
1560 when Attribute_External_Tag |
1564 Attribute_Storage_Pool |
1565 Attribute_Storage_Size |
1569 -- Other cases are errors ("attribute& cannot be set with
1570 -- definition clause"), which will be caught below.
1578 Ent := Entity (Nam);
1580 if Rep_Item_Too_Early (Ent, N) then
1584 -- Rep clause applies to full view of incomplete type or private type if
1585 -- we have one (if not, this is a premature use of the type). However,
1586 -- certain semantic checks need to be done on the specified entity (i.e.
1587 -- the private view), so we save it in Ent.
1589 if Is_Private_Type (Ent)
1590 and then Is_Derived_Type (Ent)
1591 and then not Is_Tagged_Type (Ent)
1592 and then No (Full_View (Ent))
1594 -- If this is a private type whose completion is a derivation from
1595 -- another private type, there is no full view, and the attribute
1596 -- belongs to the type itself, not its underlying parent.
1600 elsif Ekind (Ent) = E_Incomplete_Type then
1602 -- The attribute applies to the full view, set the entity of the
1603 -- attribute definition accordingly.
1605 Ent := Underlying_Type (Ent);
1607 Set_Entity (Nam, Ent);
1610 U_Ent := Underlying_Type (Ent);
1613 -- Complete other routine error checks
1615 if Etype (Nam) = Any_Type then
1618 elsif Scope (Ent) /= Current_Scope then
1619 Error_Msg_N ("entity must be declared in this scope", Nam);
1622 elsif No (U_Ent) then
1625 elsif Is_Type (U_Ent)
1626 and then not Is_First_Subtype (U_Ent)
1627 and then Id /= Attribute_Object_Size
1628 and then Id /= Attribute_Value_Size
1629 and then not From_At_Mod (N)
1631 Error_Msg_N ("cannot specify attribute for subtype", Nam);
1635 Set_Entity (N, U_Ent);
1637 -- Switch on particular attribute
1645 -- Address attribute definition clause
1647 when Attribute_Address => Address : begin
1649 -- A little error check, catch for X'Address use X'Address;
1651 if Nkind (Nam) = N_Identifier
1652 and then Nkind (Expr) = N_Attribute_Reference
1653 and then Attribute_Name (Expr) = Name_Address
1654 and then Nkind (Prefix (Expr)) = N_Identifier
1655 and then Chars (Nam) = Chars (Prefix (Expr))
1658 ("address for & is self-referencing", Prefix (Expr), Ent);
1662 -- Not that special case, carry on with analysis of expression
1664 Analyze_And_Resolve (Expr, RTE (RE_Address));
1666 -- Even when ignoring rep clauses we need to indicate that the
1667 -- entity has an address clause and thus it is legal to declare
1670 if Ignore_Rep_Clauses then
1671 if Ekind_In (U_Ent, E_Variable, E_Constant) then
1672 Record_Rep_Item (U_Ent, N);
1678 if Duplicate_Clause then
1681 -- Case of address clause for subprogram
1683 elsif Is_Subprogram (U_Ent) then
1684 if Has_Homonym (U_Ent) then
1686 ("address clause cannot be given " &
1687 "for overloaded subprogram",
1692 -- For subprograms, all address clauses are permitted, and we
1693 -- mark the subprogram as having a deferred freeze so that Gigi
1694 -- will not elaborate it too soon.
1696 -- Above needs more comments, what is too soon about???
1698 Set_Has_Delayed_Freeze (U_Ent);
1700 -- Case of address clause for entry
1702 elsif Ekind (U_Ent) = E_Entry then
1703 if Nkind (Parent (N)) = N_Task_Body then
1705 ("entry address must be specified in task spec", Nam);
1709 -- For entries, we require a constant address
1711 Check_Constant_Address_Clause (Expr, U_Ent);
1713 -- Special checks for task types
1715 if Is_Task_Type (Scope (U_Ent))
1716 and then Comes_From_Source (Scope (U_Ent))
1719 ("?entry address declared for entry in task type", N);
1721 ("\?only one task can be declared of this type", N);
1724 -- Entry address clauses are obsolescent
1726 Check_Restriction (No_Obsolescent_Features, N);
1728 if Warn_On_Obsolescent_Feature then
1730 ("attaching interrupt to task entry is an " &
1731 "obsolescent feature (RM J.7.1)?", N);
1733 ("\use interrupt procedure instead?", N);
1736 -- Case of an address clause for a controlled object which we
1737 -- consider to be erroneous.
1739 elsif Is_Controlled (Etype (U_Ent))
1740 or else Has_Controlled_Component (Etype (U_Ent))
1743 ("?controlled object& must not be overlaid", Nam, U_Ent);
1745 ("\?Program_Error will be raised at run time", Nam);
1746 Insert_Action (Declaration_Node (U_Ent),
1747 Make_Raise_Program_Error (Loc,
1748 Reason => PE_Overlaid_Controlled_Object));
1751 -- Case of address clause for a (non-controlled) object
1754 Ekind (U_Ent) = E_Variable
1756 Ekind (U_Ent) = E_Constant
1759 Expr : constant Node_Id := Expression (N);
1764 -- Exported variables cannot have an address clause, because
1765 -- this cancels the effect of the pragma Export.
1767 if Is_Exported (U_Ent) then
1769 ("cannot export object with address clause", Nam);
1773 Find_Overlaid_Entity (N, O_Ent, Off);
1775 -- Overlaying controlled objects is erroneous
1778 and then (Has_Controlled_Component (Etype (O_Ent))
1779 or else Is_Controlled (Etype (O_Ent)))
1782 ("?cannot overlay with controlled object", Expr);
1784 ("\?Program_Error will be raised at run time", Expr);
1785 Insert_Action (Declaration_Node (U_Ent),
1786 Make_Raise_Program_Error (Loc,
1787 Reason => PE_Overlaid_Controlled_Object));
1790 elsif Present (O_Ent)
1791 and then Ekind (U_Ent) = E_Constant
1792 and then not Is_Constant_Object (O_Ent)
1794 Error_Msg_N ("constant overlays a variable?", Expr);
1796 elsif Present (Renamed_Object (U_Ent)) then
1798 ("address clause not allowed"
1799 & " for a renaming declaration (RM 13.1(6))", Nam);
1802 -- Imported variables can have an address clause, but then
1803 -- the import is pretty meaningless except to suppress
1804 -- initializations, so we do not need such variables to
1805 -- be statically allocated (and in fact it causes trouble
1806 -- if the address clause is a local value).
1808 elsif Is_Imported (U_Ent) then
1809 Set_Is_Statically_Allocated (U_Ent, False);
1812 -- We mark a possible modification of a variable with an
1813 -- address clause, since it is likely aliasing is occurring.
1815 Note_Possible_Modification (Nam, Sure => False);
1817 -- Here we are checking for explicit overlap of one variable
1818 -- by another, and if we find this then mark the overlapped
1819 -- variable as also being volatile to prevent unwanted
1820 -- optimizations. This is a significant pessimization so
1821 -- avoid it when there is an offset, i.e. when the object
1822 -- is composite; they cannot be optimized easily anyway.
1825 and then Is_Object (O_Ent)
1828 Set_Treat_As_Volatile (O_Ent);
1831 -- Legality checks on the address clause for initialized
1832 -- objects is deferred until the freeze point, because
1833 -- a subsequent pragma might indicate that the object is
1834 -- imported and thus not initialized.
1836 Set_Has_Delayed_Freeze (U_Ent);
1838 -- If an initialization call has been generated for this
1839 -- object, it needs to be deferred to after the freeze node
1840 -- we have just now added, otherwise GIGI will see a
1841 -- reference to the variable (as actual to the IP call)
1842 -- before its definition.
1845 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
1847 if Present (Init_Call) then
1849 Append_Freeze_Action (U_Ent, Init_Call);
1853 if Is_Exported (U_Ent) then
1855 ("& cannot be exported if an address clause is given",
1858 ("\define and export a variable " &
1859 "that holds its address instead",
1863 -- Entity has delayed freeze, so we will generate an
1864 -- alignment check at the freeze point unless suppressed.
1866 if not Range_Checks_Suppressed (U_Ent)
1867 and then not Alignment_Checks_Suppressed (U_Ent)
1869 Set_Check_Address_Alignment (N);
1872 -- Kill the size check code, since we are not allocating
1873 -- the variable, it is somewhere else.
1875 Kill_Size_Check_Code (U_Ent);
1877 -- If the address clause is of the form:
1879 -- for Y'Address use X'Address
1883 -- Const : constant Address := X'Address;
1885 -- for Y'Address use Const;
1887 -- then we make an entry in the table for checking the size
1888 -- and alignment of the overlaying variable. We defer this
1889 -- check till after code generation to take full advantage
1890 -- of the annotation done by the back end. This entry is
1891 -- only made if the address clause comes from source.
1892 -- If the entity has a generic type, the check will be
1893 -- performed in the instance if the actual type justifies
1894 -- it, and we do not insert the clause in the table to
1895 -- prevent spurious warnings.
1897 if Address_Clause_Overlay_Warnings
1898 and then Comes_From_Source (N)
1899 and then Present (O_Ent)
1900 and then Is_Object (O_Ent)
1902 if not Is_Generic_Type (Etype (U_Ent)) then
1903 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
1906 -- If variable overlays a constant view, and we are
1907 -- warning on overlays, then mark the variable as
1908 -- overlaying a constant (we will give warnings later
1909 -- if this variable is assigned).
1911 if Is_Constant_Object (O_Ent)
1912 and then Ekind (U_Ent) = E_Variable
1914 Set_Overlays_Constant (U_Ent);
1919 -- Not a valid entity for an address clause
1922 Error_Msg_N ("address cannot be given for &", Nam);
1930 -- Alignment attribute definition clause
1932 when Attribute_Alignment => Alignment : declare
1933 Align : constant Uint := Get_Alignment_Value (Expr);
1938 if not Is_Type (U_Ent)
1939 and then Ekind (U_Ent) /= E_Variable
1940 and then Ekind (U_Ent) /= E_Constant
1942 Error_Msg_N ("alignment cannot be given for &", Nam);
1944 elsif Duplicate_Clause then
1947 elsif Align /= No_Uint then
1948 Set_Has_Alignment_Clause (U_Ent);
1949 Set_Alignment (U_Ent, Align);
1951 -- For an array type, U_Ent is the first subtype. In that case,
1952 -- also set the alignment of the anonymous base type so that
1953 -- other subtypes (such as the itypes for aggregates of the
1954 -- type) also receive the expected alignment.
1956 if Is_Array_Type (U_Ent) then
1957 Set_Alignment (Base_Type (U_Ent), Align);
1966 -- Bit_Order attribute definition clause
1968 when Attribute_Bit_Order => Bit_Order : declare
1970 if not Is_Record_Type (U_Ent) then
1972 ("Bit_Order can only be defined for record type", Nam);
1974 elsif Duplicate_Clause then
1978 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
1980 if Etype (Expr) = Any_Type then
1983 elsif not Is_Static_Expression (Expr) then
1984 Flag_Non_Static_Expr
1985 ("Bit_Order requires static expression!", Expr);
1988 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
1989 Set_Reverse_Bit_Order (U_Ent, True);
1995 --------------------
1996 -- Component_Size --
1997 --------------------
1999 -- Component_Size attribute definition clause
2001 when Attribute_Component_Size => Component_Size_Case : declare
2002 Csize : constant Uint := Static_Integer (Expr);
2006 New_Ctyp : Entity_Id;
2010 if not Is_Array_Type (U_Ent) then
2011 Error_Msg_N ("component size requires array type", Nam);
2015 Btype := Base_Type (U_Ent);
2016 Ctyp := Component_Type (Btype);
2018 if Duplicate_Clause then
2021 elsif Rep_Item_Too_Early (Btype, N) then
2024 elsif Csize /= No_Uint then
2025 Check_Size (Expr, Ctyp, Csize, Biased);
2027 -- For the biased case, build a declaration for a subtype that
2028 -- will be used to represent the biased subtype that reflects
2029 -- the biased representation of components. We need the subtype
2030 -- to get proper conversions on referencing elements of the
2031 -- array. Note: component size clauses are ignored in VM mode.
2033 if VM_Target = No_VM then
2036 Make_Defining_Identifier (Loc,
2038 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2041 Make_Subtype_Declaration (Loc,
2042 Defining_Identifier => New_Ctyp,
2043 Subtype_Indication =>
2044 New_Occurrence_Of (Component_Type (Btype), Loc));
2046 Set_Parent (Decl, N);
2047 Analyze (Decl, Suppress => All_Checks);
2049 Set_Has_Delayed_Freeze (New_Ctyp, False);
2050 Set_Esize (New_Ctyp, Csize);
2051 Set_RM_Size (New_Ctyp, Csize);
2052 Init_Alignment (New_Ctyp);
2053 Set_Is_Itype (New_Ctyp, True);
2054 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2056 Set_Component_Type (Btype, New_Ctyp);
2057 Set_Biased (New_Ctyp, N, "component size clause");
2060 Set_Component_Size (Btype, Csize);
2062 -- For VM case, we ignore component size clauses
2065 -- Give a warning unless we are in GNAT mode, in which case
2066 -- the warning is suppressed since it is not useful.
2068 if not GNAT_Mode then
2070 ("?component size ignored in this configuration", N);
2074 -- Deal with warning on overridden size
2076 if Warn_On_Overridden_Size
2077 and then Has_Size_Clause (Ctyp)
2078 and then RM_Size (Ctyp) /= Csize
2081 ("?component size overrides size clause for&",
2085 Set_Has_Component_Size_Clause (Btype, True);
2086 Set_Has_Non_Standard_Rep (Btype, True);
2088 end Component_Size_Case;
2094 when Attribute_External_Tag => External_Tag :
2096 if not Is_Tagged_Type (U_Ent) then
2097 Error_Msg_N ("should be a tagged type", Nam);
2100 if Duplicate_Clause then
2104 Analyze_And_Resolve (Expr, Standard_String);
2106 if not Is_Static_Expression (Expr) then
2107 Flag_Non_Static_Expr
2108 ("static string required for tag name!", Nam);
2111 if VM_Target = No_VM then
2112 Set_Has_External_Tag_Rep_Clause (U_Ent);
2114 Error_Msg_Name_1 := Attr;
2116 ("% attribute unsupported in this configuration", Nam);
2119 if not Is_Library_Level_Entity (U_Ent) then
2121 ("?non-unique external tag supplied for &", N, U_Ent);
2123 ("?\same external tag applies to all subprogram calls", N);
2125 ("?\corresponding internal tag cannot be obtained", N);
2134 when Attribute_Input =>
2135 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2136 Set_Has_Specified_Stream_Input (Ent);
2142 -- Machine radix attribute definition clause
2144 when Attribute_Machine_Radix => Machine_Radix : declare
2145 Radix : constant Uint := Static_Integer (Expr);
2148 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2149 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2151 elsif Duplicate_Clause then
2154 elsif Radix /= No_Uint then
2155 Set_Has_Machine_Radix_Clause (U_Ent);
2156 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2160 elsif Radix = 10 then
2161 Set_Machine_Radix_10 (U_Ent);
2163 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2172 -- Object_Size attribute definition clause
2174 when Attribute_Object_Size => Object_Size : declare
2175 Size : constant Uint := Static_Integer (Expr);
2178 pragma Warnings (Off, Biased);
2181 if not Is_Type (U_Ent) then
2182 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2184 elsif Duplicate_Clause then
2188 Check_Size (Expr, U_Ent, Size, Biased);
2196 UI_Mod (Size, 64) /= 0
2199 ("Object_Size must be 8, 16, 32, or multiple of 64",
2203 Set_Esize (U_Ent, Size);
2204 Set_Has_Object_Size_Clause (U_Ent);
2205 Alignment_Check_For_Esize_Change (U_Ent);
2213 when Attribute_Output =>
2214 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2215 Set_Has_Specified_Stream_Output (Ent);
2221 when Attribute_Read =>
2222 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2223 Set_Has_Specified_Stream_Read (Ent);
2229 -- Size attribute definition clause
2231 when Attribute_Size => Size : declare
2232 Size : constant Uint := Static_Integer (Expr);
2239 if Duplicate_Clause then
2242 elsif not Is_Type (U_Ent)
2243 and then Ekind (U_Ent) /= E_Variable
2244 and then Ekind (U_Ent) /= E_Constant
2246 Error_Msg_N ("size cannot be given for &", Nam);
2248 elsif Is_Array_Type (U_Ent)
2249 and then not Is_Constrained (U_Ent)
2252 ("size cannot be given for unconstrained array", Nam);
2254 elsif Size /= No_Uint then
2256 if VM_Target /= No_VM and then not GNAT_Mode then
2258 -- Size clause is not handled properly on VM targets.
2259 -- Display a warning unless we are in GNAT mode, in which
2260 -- case this is useless.
2263 ("?size clauses are ignored in this configuration", N);
2266 if Is_Type (U_Ent) then
2269 Etyp := Etype (U_Ent);
2272 -- Check size, note that Gigi is in charge of checking that the
2273 -- size of an array or record type is OK. Also we do not check
2274 -- the size in the ordinary fixed-point case, since it is too
2275 -- early to do so (there may be subsequent small clause that
2276 -- affects the size). We can check the size if a small clause
2277 -- has already been given.
2279 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2280 or else Has_Small_Clause (U_Ent)
2282 Check_Size (Expr, Etyp, Size, Biased);
2283 Set_Biased (U_Ent, N, "size clause", Biased);
2286 -- For types set RM_Size and Esize if possible
2288 if Is_Type (U_Ent) then
2289 Set_RM_Size (U_Ent, Size);
2291 -- For scalar types, increase Object_Size to power of 2, but
2292 -- not less than a storage unit in any case (i.e., normally
2293 -- this means it will be byte addressable).
2295 if Is_Scalar_Type (U_Ent) then
2296 if Size <= System_Storage_Unit then
2297 Init_Esize (U_Ent, System_Storage_Unit);
2298 elsif Size <= 16 then
2299 Init_Esize (U_Ent, 16);
2300 elsif Size <= 32 then
2301 Init_Esize (U_Ent, 32);
2303 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2306 -- For all other types, object size = value size. The
2307 -- backend will adjust as needed.
2310 Set_Esize (U_Ent, Size);
2313 Alignment_Check_For_Esize_Change (U_Ent);
2315 -- For objects, set Esize only
2318 if Is_Elementary_Type (Etyp) then
2319 if Size /= System_Storage_Unit
2321 Size /= System_Storage_Unit * 2
2323 Size /= System_Storage_Unit * 4
2325 Size /= System_Storage_Unit * 8
2327 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2328 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2330 ("size for primitive object must be a power of 2"
2331 & " in the range ^-^", N);
2335 Set_Esize (U_Ent, Size);
2338 Set_Has_Size_Clause (U_Ent);
2346 -- Small attribute definition clause
2348 when Attribute_Small => Small : declare
2349 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2353 Analyze_And_Resolve (Expr, Any_Real);
2355 if Etype (Expr) = Any_Type then
2358 elsif not Is_Static_Expression (Expr) then
2359 Flag_Non_Static_Expr
2360 ("small requires static expression!", Expr);
2364 Small := Expr_Value_R (Expr);
2366 if Small <= Ureal_0 then
2367 Error_Msg_N ("small value must be greater than zero", Expr);
2373 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2375 ("small requires an ordinary fixed point type", Nam);
2377 elsif Has_Small_Clause (U_Ent) then
2378 Error_Msg_N ("small already given for &", Nam);
2380 elsif Small > Delta_Value (U_Ent) then
2382 ("small value must not be greater then delta value", Nam);
2385 Set_Small_Value (U_Ent, Small);
2386 Set_Small_Value (Implicit_Base, Small);
2387 Set_Has_Small_Clause (U_Ent);
2388 Set_Has_Small_Clause (Implicit_Base);
2389 Set_Has_Non_Standard_Rep (Implicit_Base);
2397 -- Storage_Pool attribute definition clause
2399 when Attribute_Storage_Pool => Storage_Pool : declare
2404 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2406 ("storage pool cannot be given for access-to-subprogram type",
2411 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2414 ("storage pool can only be given for access types", Nam);
2417 elsif Is_Derived_Type (U_Ent) then
2419 ("storage pool cannot be given for a derived access type",
2422 elsif Duplicate_Clause then
2425 elsif Present (Associated_Storage_Pool (U_Ent)) then
2426 Error_Msg_N ("storage pool already given for &", Nam);
2431 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
2433 if not Denotes_Variable (Expr) then
2434 Error_Msg_N ("storage pool must be a variable", Expr);
2438 if Nkind (Expr) = N_Type_Conversion then
2439 T := Etype (Expression (Expr));
2444 -- The Stack_Bounded_Pool is used internally for implementing
2445 -- access types with a Storage_Size. Since it only work
2446 -- properly when used on one specific type, we need to check
2447 -- that it is not hijacked improperly:
2448 -- type T is access Integer;
2449 -- for T'Storage_Size use n;
2450 -- type Q is access Float;
2451 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
2453 if RTE_Available (RE_Stack_Bounded_Pool)
2454 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
2456 Error_Msg_N ("non-shareable internal Pool", Expr);
2460 -- If the argument is a name that is not an entity name, then
2461 -- we construct a renaming operation to define an entity of
2462 -- type storage pool.
2464 if not Is_Entity_Name (Expr)
2465 and then Is_Object_Reference (Expr)
2467 Pool := Make_Temporary (Loc, 'P', Expr);
2470 Rnode : constant Node_Id :=
2471 Make_Object_Renaming_Declaration (Loc,
2472 Defining_Identifier => Pool,
2474 New_Occurrence_Of (Etype (Expr), Loc),
2478 Insert_Before (N, Rnode);
2480 Set_Associated_Storage_Pool (U_Ent, Pool);
2483 elsif Is_Entity_Name (Expr) then
2484 Pool := Entity (Expr);
2486 -- If pool is a renamed object, get original one. This can
2487 -- happen with an explicit renaming, and within instances.
2489 while Present (Renamed_Object (Pool))
2490 and then Is_Entity_Name (Renamed_Object (Pool))
2492 Pool := Entity (Renamed_Object (Pool));
2495 if Present (Renamed_Object (Pool))
2496 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
2497 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
2499 Pool := Entity (Expression (Renamed_Object (Pool)));
2502 Set_Associated_Storage_Pool (U_Ent, Pool);
2504 elsif Nkind (Expr) = N_Type_Conversion
2505 and then Is_Entity_Name (Expression (Expr))
2506 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
2508 Pool := Entity (Expression (Expr));
2509 Set_Associated_Storage_Pool (U_Ent, Pool);
2512 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
2521 -- Storage_Size attribute definition clause
2523 when Attribute_Storage_Size => Storage_Size : declare
2524 Btype : constant Entity_Id := Base_Type (U_Ent);
2528 if Is_Task_Type (U_Ent) then
2529 Check_Restriction (No_Obsolescent_Features, N);
2531 if Warn_On_Obsolescent_Feature then
2533 ("storage size clause for task is an " &
2534 "obsolescent feature (RM J.9)?", N);
2535 Error_Msg_N ("\use Storage_Size pragma instead?", N);
2541 if not Is_Access_Type (U_Ent)
2542 and then Ekind (U_Ent) /= E_Task_Type
2544 Error_Msg_N ("storage size cannot be given for &", Nam);
2546 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
2548 ("storage size cannot be given for a derived access type",
2551 elsif Duplicate_Clause then
2555 Analyze_And_Resolve (Expr, Any_Integer);
2557 if Is_Access_Type (U_Ent) then
2558 if Present (Associated_Storage_Pool (U_Ent)) then
2559 Error_Msg_N ("storage pool already given for &", Nam);
2563 if Is_OK_Static_Expression (Expr)
2564 and then Expr_Value (Expr) = 0
2566 Set_No_Pool_Assigned (Btype);
2569 else -- Is_Task_Type (U_Ent)
2570 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
2572 if Present (Sprag) then
2573 Error_Msg_Sloc := Sloc (Sprag);
2575 ("Storage_Size already specified#", Nam);
2580 Set_Has_Storage_Size_Clause (Btype);
2588 when Attribute_Stream_Size => Stream_Size : declare
2589 Size : constant Uint := Static_Integer (Expr);
2592 if Ada_Version <= Ada_95 then
2593 Check_Restriction (No_Implementation_Attributes, N);
2596 if Duplicate_Clause then
2599 elsif Is_Elementary_Type (U_Ent) then
2600 if Size /= System_Storage_Unit
2602 Size /= System_Storage_Unit * 2
2604 Size /= System_Storage_Unit * 4
2606 Size /= System_Storage_Unit * 8
2608 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2610 ("stream size for elementary type must be a"
2611 & " power of 2 and at least ^", N);
2613 elsif RM_Size (U_Ent) > Size then
2614 Error_Msg_Uint_1 := RM_Size (U_Ent);
2616 ("stream size for elementary type must be a"
2617 & " power of 2 and at least ^", N);
2620 Set_Has_Stream_Size_Clause (U_Ent);
2623 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
2631 -- Value_Size attribute definition clause
2633 when Attribute_Value_Size => Value_Size : declare
2634 Size : constant Uint := Static_Integer (Expr);
2638 if not Is_Type (U_Ent) then
2639 Error_Msg_N ("Value_Size cannot be given for &", Nam);
2641 elsif Duplicate_Clause then
2644 elsif Is_Array_Type (U_Ent)
2645 and then not Is_Constrained (U_Ent)
2648 ("Value_Size cannot be given for unconstrained array", Nam);
2651 if Is_Elementary_Type (U_Ent) then
2652 Check_Size (Expr, U_Ent, Size, Biased);
2653 Set_Biased (U_Ent, N, "value size clause", Biased);
2656 Set_RM_Size (U_Ent, Size);
2664 when Attribute_Write =>
2665 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
2666 Set_Has_Specified_Stream_Write (Ent);
2668 -- All other attributes cannot be set
2672 ("attribute& cannot be set with definition clause", N);
2675 -- The test for the type being frozen must be performed after
2676 -- any expression the clause has been analyzed since the expression
2677 -- itself might cause freezing that makes the clause illegal.
2679 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
2682 end Analyze_Attribute_Definition_Clause;
2684 ----------------------------
2685 -- Analyze_Code_Statement --
2686 ----------------------------
2688 procedure Analyze_Code_Statement (N : Node_Id) is
2689 HSS : constant Node_Id := Parent (N);
2690 SBody : constant Node_Id := Parent (HSS);
2691 Subp : constant Entity_Id := Current_Scope;
2698 -- Analyze and check we get right type, note that this implements the
2699 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
2700 -- is the only way that Asm_Insn could possibly be visible.
2702 Analyze_And_Resolve (Expression (N));
2704 if Etype (Expression (N)) = Any_Type then
2706 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
2707 Error_Msg_N ("incorrect type for code statement", N);
2711 Check_Code_Statement (N);
2713 -- Make sure we appear in the handled statement sequence of a
2714 -- subprogram (RM 13.8(3)).
2716 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
2717 or else Nkind (SBody) /= N_Subprogram_Body
2720 ("code statement can only appear in body of subprogram", N);
2724 -- Do remaining checks (RM 13.8(3)) if not already done
2726 if not Is_Machine_Code_Subprogram (Subp) then
2727 Set_Is_Machine_Code_Subprogram (Subp);
2729 -- No exception handlers allowed
2731 if Present (Exception_Handlers (HSS)) then
2733 ("exception handlers not permitted in machine code subprogram",
2734 First (Exception_Handlers (HSS)));
2737 -- No declarations other than use clauses and pragmas (we allow
2738 -- certain internally generated declarations as well).
2740 Decl := First (Declarations (SBody));
2741 while Present (Decl) loop
2742 DeclO := Original_Node (Decl);
2743 if Comes_From_Source (DeclO)
2744 and not Nkind_In (DeclO, N_Pragma,
2745 N_Use_Package_Clause,
2747 N_Implicit_Label_Declaration)
2750 ("this declaration not allowed in machine code subprogram",
2757 -- No statements other than code statements, pragmas, and labels.
2758 -- Again we allow certain internally generated statements.
2760 Stmt := First (Statements (HSS));
2761 while Present (Stmt) loop
2762 StmtO := Original_Node (Stmt);
2763 if Comes_From_Source (StmtO)
2764 and then not Nkind_In (StmtO, N_Pragma,
2769 ("this statement is not allowed in machine code subprogram",
2776 end Analyze_Code_Statement;
2778 -----------------------------------------------
2779 -- Analyze_Enumeration_Representation_Clause --
2780 -----------------------------------------------
2782 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
2783 Ident : constant Node_Id := Identifier (N);
2784 Aggr : constant Node_Id := Array_Aggregate (N);
2785 Enumtype : Entity_Id;
2791 Err : Boolean := False;
2793 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
2794 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
2795 -- Allowed range of universal integer (= allowed range of enum lit vals)
2799 -- Minimum and maximum values of entries
2802 -- Pointer to node for literal providing max value
2805 if Ignore_Rep_Clauses then
2809 -- First some basic error checks
2812 Enumtype := Entity (Ident);
2814 if Enumtype = Any_Type
2815 or else Rep_Item_Too_Early (Enumtype, N)
2819 Enumtype := Underlying_Type (Enumtype);
2822 if not Is_Enumeration_Type (Enumtype) then
2824 ("enumeration type required, found}",
2825 Ident, First_Subtype (Enumtype));
2829 -- Ignore rep clause on generic actual type. This will already have
2830 -- been flagged on the template as an error, and this is the safest
2831 -- way to ensure we don't get a junk cascaded message in the instance.
2833 if Is_Generic_Actual_Type (Enumtype) then
2836 -- Type must be in current scope
2838 elsif Scope (Enumtype) /= Current_Scope then
2839 Error_Msg_N ("type must be declared in this scope", Ident);
2842 -- Type must be a first subtype
2844 elsif not Is_First_Subtype (Enumtype) then
2845 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
2848 -- Ignore duplicate rep clause
2850 elsif Has_Enumeration_Rep_Clause (Enumtype) then
2851 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
2854 -- Don't allow rep clause for standard [wide_[wide_]]character
2856 elsif Is_Standard_Character_Type (Enumtype) then
2857 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
2860 -- Check that the expression is a proper aggregate (no parentheses)
2862 elsif Paren_Count (Aggr) /= 0 then
2864 ("extra parentheses surrounding aggregate not allowed",
2868 -- All tests passed, so set rep clause in place
2871 Set_Has_Enumeration_Rep_Clause (Enumtype);
2872 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
2875 -- Now we process the aggregate. Note that we don't use the normal
2876 -- aggregate code for this purpose, because we don't want any of the
2877 -- normal expansion activities, and a number of special semantic
2878 -- rules apply (including the component type being any integer type)
2880 Elit := First_Literal (Enumtype);
2882 -- First the positional entries if any
2884 if Present (Expressions (Aggr)) then
2885 Expr := First (Expressions (Aggr));
2886 while Present (Expr) loop
2888 Error_Msg_N ("too many entries in aggregate", Expr);
2892 Val := Static_Integer (Expr);
2894 -- Err signals that we found some incorrect entries processing
2895 -- the list. The final checks for completeness and ordering are
2896 -- skipped in this case.
2898 if Val = No_Uint then
2900 elsif Val < Lo or else Hi < Val then
2901 Error_Msg_N ("value outside permitted range", Expr);
2905 Set_Enumeration_Rep (Elit, Val);
2906 Set_Enumeration_Rep_Expr (Elit, Expr);
2912 -- Now process the named entries if present
2914 if Present (Component_Associations (Aggr)) then
2915 Assoc := First (Component_Associations (Aggr));
2916 while Present (Assoc) loop
2917 Choice := First (Choices (Assoc));
2919 if Present (Next (Choice)) then
2921 ("multiple choice not allowed here", Next (Choice));
2925 if Nkind (Choice) = N_Others_Choice then
2926 Error_Msg_N ("others choice not allowed here", Choice);
2929 elsif Nkind (Choice) = N_Range then
2930 -- ??? should allow zero/one element range here
2931 Error_Msg_N ("range not allowed here", Choice);
2935 Analyze_And_Resolve (Choice, Enumtype);
2937 if Is_Entity_Name (Choice)
2938 and then Is_Type (Entity (Choice))
2940 Error_Msg_N ("subtype name not allowed here", Choice);
2942 -- ??? should allow static subtype with zero/one entry
2944 elsif Etype (Choice) = Base_Type (Enumtype) then
2945 if not Is_Static_Expression (Choice) then
2946 Flag_Non_Static_Expr
2947 ("non-static expression used for choice!", Choice);
2951 Elit := Expr_Value_E (Choice);
2953 if Present (Enumeration_Rep_Expr (Elit)) then
2954 Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit));
2956 ("representation for& previously given#",
2961 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
2963 Expr := Expression (Assoc);
2964 Val := Static_Integer (Expr);
2966 if Val = No_Uint then
2969 elsif Val < Lo or else Hi < Val then
2970 Error_Msg_N ("value outside permitted range", Expr);
2974 Set_Enumeration_Rep (Elit, Val);
2983 -- Aggregate is fully processed. Now we check that a full set of
2984 -- representations was given, and that they are in range and in order.
2985 -- These checks are only done if no other errors occurred.
2991 Elit := First_Literal (Enumtype);
2992 while Present (Elit) loop
2993 if No (Enumeration_Rep_Expr (Elit)) then
2994 Error_Msg_NE ("missing representation for&!", N, Elit);
2997 Val := Enumeration_Rep (Elit);
2999 if Min = No_Uint then
3003 if Val /= No_Uint then
3004 if Max /= No_Uint and then Val <= Max then
3006 ("enumeration value for& not ordered!",
3007 Enumeration_Rep_Expr (Elit), Elit);
3010 Max_Node := Enumeration_Rep_Expr (Elit);
3014 -- If there is at least one literal whose representation is not
3015 -- equal to the Pos value, then note that this enumeration type
3016 -- has a non-standard representation.
3018 if Val /= Enumeration_Pos (Elit) then
3019 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3026 -- Now set proper size information
3029 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3032 if Has_Size_Clause (Enumtype) then
3034 -- All OK, if size is OK now
3036 if RM_Size (Enumtype) >= Minsize then
3040 -- Try if we can get by with biasing
3043 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3045 -- Error message if even biasing does not work
3047 if RM_Size (Enumtype) < Minsize then
3048 Error_Msg_Uint_1 := RM_Size (Enumtype);
3049 Error_Msg_Uint_2 := Max;
3051 ("previously given size (^) is too small "
3052 & "for this value (^)", Max_Node);
3054 -- If biasing worked, indicate that we now have biased rep
3058 (Enumtype, Size_Clause (Enumtype), "size clause");
3063 Set_RM_Size (Enumtype, Minsize);
3064 Set_Enum_Esize (Enumtype);
3067 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3068 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3069 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3073 -- We repeat the too late test in case it froze itself!
3075 if Rep_Item_Too_Late (Enumtype, N) then
3078 end Analyze_Enumeration_Representation_Clause;
3080 ----------------------------
3081 -- Analyze_Free_Statement --
3082 ----------------------------
3084 procedure Analyze_Free_Statement (N : Node_Id) is
3086 Analyze (Expression (N));
3087 end Analyze_Free_Statement;
3089 ---------------------------
3090 -- Analyze_Freeze_Entity --
3091 ---------------------------
3093 procedure Analyze_Freeze_Entity (N : Node_Id) is
3094 E : constant Entity_Id := Entity (N);
3097 -- Remember that we are processing a freezing entity. Required to
3098 -- ensure correct decoration of internal entities associated with
3099 -- interfaces (see New_Overloaded_Entity).
3101 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3103 -- For tagged types covering interfaces add internal entities that link
3104 -- the primitives of the interfaces with the primitives that cover them.
3105 -- Note: These entities were originally generated only when generating
3106 -- code because their main purpose was to provide support to initialize
3107 -- the secondary dispatch tables. They are now generated also when
3108 -- compiling with no code generation to provide ASIS the relationship
3109 -- between interface primitives and tagged type primitives. They are
3110 -- also used to locate primitives covering interfaces when processing
3111 -- generics (see Derive_Subprograms).
3113 if Ada_Version >= Ada_2005
3114 and then Ekind (E) = E_Record_Type
3115 and then Is_Tagged_Type (E)
3116 and then not Is_Interface (E)
3117 and then Has_Interfaces (E)
3119 -- This would be a good common place to call the routine that checks
3120 -- overriding of interface primitives (and thus factorize calls to
3121 -- Check_Abstract_Overriding located at different contexts in the
3122 -- compiler). However, this is not possible because it causes
3123 -- spurious errors in case of late overriding.
3125 Add_Internal_Interface_Entities (E);
3130 if Ekind (E) = E_Record_Type
3131 and then Is_CPP_Class (E)
3132 and then Is_Tagged_Type (E)
3133 and then Tagged_Type_Expansion
3134 and then Expander_Active
3136 if CPP_Num_Prims (E) = 0 then
3138 -- If the CPP type has user defined components then it must import
3139 -- primitives from C++. This is required because if the C++ class
3140 -- has no primitives then the C++ compiler does not added the _tag
3141 -- component to the type.
3143 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3145 if First_Entity (E) /= Last_Entity (E) then
3147 ("?'C'P'P type must import at least one primitive from C++",
3152 -- Check that all its primitives are abstract or imported from C++.
3153 -- Check also availability of the C++ constructor.
3156 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3158 Error_Reported : Boolean := False;
3162 Elmt := First_Elmt (Primitive_Operations (E));
3163 while Present (Elmt) loop
3164 Prim := Node (Elmt);
3166 if Comes_From_Source (Prim) then
3167 if Is_Abstract_Subprogram (Prim) then
3170 elsif not Is_Imported (Prim)
3171 or else Convention (Prim) /= Convention_CPP
3174 ("?primitives of 'C'P'P types must be imported from C++"
3175 & " or abstract", Prim);
3177 elsif not Has_Constructors
3178 and then not Error_Reported
3180 Error_Msg_Name_1 := Chars (E);
3182 ("?'C'P'P constructor required for type %", Prim);
3183 Error_Reported := True;
3192 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3194 -- If we have a type with predicates, build predicate function
3196 if Is_Type (E) and then Has_Predicates (E) then
3197 Build_Predicate_Function (E, N);
3200 -- If type has delayed aspects, this is where we do the preanalysis
3201 -- at the freeze point, as part of the consistent visibility check.
3202 -- Note that this must be done after calling Build_Predicate_Function,
3203 -- since that call marks occurrences of the subtype name in the saved
3204 -- expression so that they will not cause trouble in the preanalysis.
3206 if Has_Delayed_Aspects (E) then
3211 -- Look for aspect specification entries for this entity
3213 Ritem := First_Rep_Item (E);
3214 while Present (Ritem) loop
3215 if Nkind (Ritem) = N_Aspect_Specification
3216 and then Entity (Ritem) = E
3217 and then Is_Delayed_Aspect (Ritem)
3219 Check_Aspect_At_Freeze_Point (Ritem);
3222 Next_Rep_Item (Ritem);
3226 end Analyze_Freeze_Entity;
3228 ------------------------------------------
3229 -- Analyze_Record_Representation_Clause --
3230 ------------------------------------------
3232 -- Note: we check as much as we can here, but we can't do any checks
3233 -- based on the position values (e.g. overlap checks) until freeze time
3234 -- because especially in Ada 2005 (machine scalar mode), the processing
3235 -- for non-standard bit order can substantially change the positions.
3236 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3237 -- for the remainder of this processing.
3239 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3240 Ident : constant Node_Id := Identifier (N);
3245 Hbit : Uint := Uint_0;
3249 Rectype : Entity_Id;
3251 CR_Pragma : Node_Id := Empty;
3252 -- Points to N_Pragma node if Complete_Representation pragma present
3255 if Ignore_Rep_Clauses then
3260 Rectype := Entity (Ident);
3262 if Rectype = Any_Type
3263 or else Rep_Item_Too_Early (Rectype, N)
3267 Rectype := Underlying_Type (Rectype);
3270 -- First some basic error checks
3272 if not Is_Record_Type (Rectype) then
3274 ("record type required, found}", Ident, First_Subtype (Rectype));
3277 elsif Scope (Rectype) /= Current_Scope then
3278 Error_Msg_N ("type must be declared in this scope", N);
3281 elsif not Is_First_Subtype (Rectype) then
3282 Error_Msg_N ("cannot give record rep clause for subtype", N);
3285 elsif Has_Record_Rep_Clause (Rectype) then
3286 Error_Msg_N ("duplicate record rep clause ignored", N);
3289 elsif Rep_Item_Too_Late (Rectype, N) then
3293 if Present (Mod_Clause (N)) then
3295 Loc : constant Source_Ptr := Sloc (N);
3296 M : constant Node_Id := Mod_Clause (N);
3297 P : constant List_Id := Pragmas_Before (M);
3301 pragma Warnings (Off, Mod_Val);
3304 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3306 if Warn_On_Obsolescent_Feature then
3308 ("mod clause is an obsolescent feature (RM J.8)?", N);
3310 ("\use alignment attribute definition clause instead?", N);
3317 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3318 -- the Mod clause into an alignment clause anyway, so that the
3319 -- back-end can compute and back-annotate properly the size and
3320 -- alignment of types that may include this record.
3322 -- This seems dubious, this destroys the source tree in a manner
3323 -- not detectable by ASIS ???
3325 if Operating_Mode = Check_Semantics
3329 Make_Attribute_Definition_Clause (Loc,
3330 Name => New_Reference_To (Base_Type (Rectype), Loc),
3331 Chars => Name_Alignment,
3332 Expression => Relocate_Node (Expression (M)));
3334 Set_From_At_Mod (AtM_Nod);
3335 Insert_After (N, AtM_Nod);
3336 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3337 Set_Mod_Clause (N, Empty);
3340 -- Get the alignment value to perform error checking
3342 Mod_Val := Get_Alignment_Value (Expression (M));
3347 -- For untagged types, clear any existing component clauses for the
3348 -- type. If the type is derived, this is what allows us to override
3349 -- a rep clause for the parent. For type extensions, the representation
3350 -- of the inherited components is inherited, so we want to keep previous
3351 -- component clauses for completeness.
3353 if not Is_Tagged_Type (Rectype) then
3354 Comp := First_Component_Or_Discriminant (Rectype);
3355 while Present (Comp) loop
3356 Set_Component_Clause (Comp, Empty);
3357 Next_Component_Or_Discriminant (Comp);
3361 -- All done if no component clauses
3363 CC := First (Component_Clauses (N));
3369 -- A representation like this applies to the base type
3371 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3372 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3373 Set_Has_Specified_Layout (Base_Type (Rectype));
3375 -- Process the component clauses
3377 while Present (CC) loop
3381 if Nkind (CC) = N_Pragma then
3384 -- The only pragma of interest is Complete_Representation
3386 if Pragma_Name (CC) = Name_Complete_Representation then
3390 -- Processing for real component clause
3393 Posit := Static_Integer (Position (CC));
3394 Fbit := Static_Integer (First_Bit (CC));
3395 Lbit := Static_Integer (Last_Bit (CC));
3398 and then Fbit /= No_Uint
3399 and then Lbit /= No_Uint
3403 ("position cannot be negative", Position (CC));
3407 ("first bit cannot be negative", First_Bit (CC));
3409 -- The Last_Bit specified in a component clause must not be
3410 -- less than the First_Bit minus one (RM-13.5.1(10)).
3412 elsif Lbit < Fbit - 1 then
3414 ("last bit cannot be less than first bit minus one",
3417 -- Values look OK, so find the corresponding record component
3418 -- Even though the syntax allows an attribute reference for
3419 -- implementation-defined components, GNAT does not allow the
3420 -- tag to get an explicit position.
3422 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
3423 if Attribute_Name (Component_Name (CC)) = Name_Tag then
3424 Error_Msg_N ("position of tag cannot be specified", CC);
3426 Error_Msg_N ("illegal component name", CC);
3430 Comp := First_Entity (Rectype);
3431 while Present (Comp) loop
3432 exit when Chars (Comp) = Chars (Component_Name (CC));
3438 -- Maybe component of base type that is absent from
3439 -- statically constrained first subtype.
3441 Comp := First_Entity (Base_Type (Rectype));
3442 while Present (Comp) loop
3443 exit when Chars (Comp) = Chars (Component_Name (CC));
3450 ("component clause is for non-existent field", CC);
3452 -- Ada 2012 (AI05-0026): Any name that denotes a
3453 -- discriminant of an object of an unchecked union type
3454 -- shall not occur within a record_representation_clause.
3456 -- The general restriction of using record rep clauses on
3457 -- Unchecked_Union types has now been lifted. Since it is
3458 -- possible to introduce a record rep clause which mentions
3459 -- the discriminant of an Unchecked_Union in non-Ada 2012
3460 -- code, this check is applied to all versions of the
3463 elsif Ekind (Comp) = E_Discriminant
3464 and then Is_Unchecked_Union (Rectype)
3467 ("cannot reference discriminant of Unchecked_Union",
3468 Component_Name (CC));
3470 elsif Present (Component_Clause (Comp)) then
3472 -- Diagnose duplicate rep clause, or check consistency
3473 -- if this is an inherited component. In a double fault,
3474 -- there may be a duplicate inconsistent clause for an
3475 -- inherited component.
3477 if Scope (Original_Record_Component (Comp)) = Rectype
3478 or else Parent (Component_Clause (Comp)) = N
3480 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
3481 Error_Msg_N ("component clause previously given#", CC);
3485 Rep1 : constant Node_Id := Component_Clause (Comp);
3487 if Intval (Position (Rep1)) /=
3488 Intval (Position (CC))
3489 or else Intval (First_Bit (Rep1)) /=
3490 Intval (First_Bit (CC))
3491 or else Intval (Last_Bit (Rep1)) /=
3492 Intval (Last_Bit (CC))
3494 Error_Msg_N ("component clause inconsistent "
3495 & "with representation of ancestor", CC);
3496 elsif Warn_On_Redundant_Constructs then
3497 Error_Msg_N ("?redundant component clause "
3498 & "for inherited component!", CC);
3503 -- Normal case where this is the first component clause we
3504 -- have seen for this entity, so set it up properly.
3507 -- Make reference for field in record rep clause and set
3508 -- appropriate entity field in the field identifier.
3511 (Comp, Component_Name (CC), Set_Ref => False);
3512 Set_Entity (Component_Name (CC), Comp);
3514 -- Update Fbit and Lbit to the actual bit number
3516 Fbit := Fbit + UI_From_Int (SSU) * Posit;
3517 Lbit := Lbit + UI_From_Int (SSU) * Posit;
3519 if Has_Size_Clause (Rectype)
3520 and then Esize (Rectype) <= Lbit
3523 ("bit number out of range of specified size",
3526 Set_Component_Clause (Comp, CC);
3527 Set_Component_Bit_Offset (Comp, Fbit);
3528 Set_Esize (Comp, 1 + (Lbit - Fbit));
3529 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
3530 Set_Normalized_Position (Comp, Fbit / SSU);
3532 if Warn_On_Overridden_Size
3533 and then Has_Size_Clause (Etype (Comp))
3534 and then RM_Size (Etype (Comp)) /= Esize (Comp)
3537 ("?component size overrides size clause for&",
3538 Component_Name (CC), Etype (Comp));
3541 -- This information is also set in the corresponding
3542 -- component of the base type, found by accessing the
3543 -- Original_Record_Component link if it is present.
3545 Ocomp := Original_Record_Component (Comp);
3552 (Component_Name (CC),
3558 (Comp, First_Node (CC), "component clause", Biased);
3560 if Present (Ocomp) then
3561 Set_Component_Clause (Ocomp, CC);
3562 Set_Component_Bit_Offset (Ocomp, Fbit);
3563 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
3564 Set_Normalized_Position (Ocomp, Fbit / SSU);
3565 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
3567 Set_Normalized_Position_Max
3568 (Ocomp, Normalized_Position (Ocomp));
3570 -- Note: we don't use Set_Biased here, because we
3571 -- already gave a warning above if needed, and we
3572 -- would get a duplicate for the same name here.
3574 Set_Has_Biased_Representation
3575 (Ocomp, Has_Biased_Representation (Comp));
3578 if Esize (Comp) < 0 then
3579 Error_Msg_N ("component size is negative", CC);
3590 -- Check missing components if Complete_Representation pragma appeared
3592 if Present (CR_Pragma) then
3593 Comp := First_Component_Or_Discriminant (Rectype);
3594 while Present (Comp) loop
3595 if No (Component_Clause (Comp)) then
3597 ("missing component clause for &", CR_Pragma, Comp);
3600 Next_Component_Or_Discriminant (Comp);
3603 -- If no Complete_Representation pragma, warn if missing components
3605 elsif Warn_On_Unrepped_Components then
3607 Num_Repped_Components : Nat := 0;
3608 Num_Unrepped_Components : Nat := 0;
3611 -- First count number of repped and unrepped components
3613 Comp := First_Component_Or_Discriminant (Rectype);
3614 while Present (Comp) loop
3615 if Present (Component_Clause (Comp)) then
3616 Num_Repped_Components := Num_Repped_Components + 1;
3618 Num_Unrepped_Components := Num_Unrepped_Components + 1;
3621 Next_Component_Or_Discriminant (Comp);
3624 -- We are only interested in the case where there is at least one
3625 -- unrepped component, and at least half the components have rep
3626 -- clauses. We figure that if less than half have them, then the
3627 -- partial rep clause is really intentional. If the component
3628 -- type has no underlying type set at this point (as for a generic
3629 -- formal type), we don't know enough to give a warning on the
3632 if Num_Unrepped_Components > 0
3633 and then Num_Unrepped_Components < Num_Repped_Components
3635 Comp := First_Component_Or_Discriminant (Rectype);
3636 while Present (Comp) loop
3637 if No (Component_Clause (Comp))
3638 and then Comes_From_Source (Comp)
3639 and then Present (Underlying_Type (Etype (Comp)))
3640 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
3641 or else Size_Known_At_Compile_Time
3642 (Underlying_Type (Etype (Comp))))
3643 and then not Has_Warnings_Off (Rectype)
3645 Error_Msg_Sloc := Sloc (Comp);
3647 ("?no component clause given for & declared #",
3651 Next_Component_Or_Discriminant (Comp);
3656 end Analyze_Record_Representation_Clause;
3658 -------------------------------
3659 -- Build_Invariant_Procedure --
3660 -------------------------------
3662 -- The procedure that is constructed here has the form
3664 -- procedure typInvariant (Ixxx : typ) is
3666 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3667 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3669 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
3671 -- end typInvariant;
3673 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
3674 Loc : constant Source_Ptr := Sloc (Typ);
3681 Visible_Decls : constant List_Id := Visible_Declarations (N);
3682 Private_Decls : constant List_Id := Private_Declarations (N);
3684 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
3685 -- Appends statements to Stmts for any invariants in the rep item chain
3686 -- of the given type. If Inherit is False, then we only process entries
3687 -- on the chain for the type Typ. If Inherit is True, then we ignore any
3688 -- Invariant aspects, but we process all Invariant'Class aspects, adding
3689 -- "inherited" to the exception message and generating an informational
3690 -- message about the inheritance of an invariant.
3692 Object_Name : constant Name_Id := New_Internal_Name ('I');
3693 -- Name for argument of invariant procedure
3695 Object_Entity : constant Node_Id :=
3696 Make_Defining_Identifier (Loc, Object_Name);
3697 -- The procedure declaration entity for the argument
3699 --------------------
3700 -- Add_Invariants --
3701 --------------------
3703 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
3713 procedure Replace_Type_Reference (N : Node_Id);
3714 -- Replace a single occurrence N of the subtype name with a reference
3715 -- to the formal of the predicate function. N can be an identifier
3716 -- referencing the subtype, or a selected component, representing an
3717 -- appropriately qualified occurrence of the subtype name.
3719 procedure Replace_Type_References is
3720 new Replace_Type_References_Generic (Replace_Type_Reference);
3721 -- Traverse an expression replacing all occurrences of the subtype
3722 -- name with appropriate references to the object that is the formal
3723 -- parameter of the predicate function. Note that we must ensure
3724 -- that the type and entity information is properly set in the
3725 -- replacement node, since we will do a Preanalyze call of this
3726 -- expression without proper visibility of the procedure argument.
3728 ----------------------------
3729 -- Replace_Type_Reference --
3730 ----------------------------
3732 procedure Replace_Type_Reference (N : Node_Id) is
3734 -- Invariant'Class, replace with T'Class (obj)
3736 if Class_Present (Ritem) then
3738 Make_Type_Conversion (Loc,
3740 Make_Attribute_Reference (Loc,
3741 Prefix => New_Occurrence_Of (T, Loc),
3742 Attribute_Name => Name_Class),
3743 Expression => Make_Identifier (Loc, Object_Name)));
3745 Set_Entity (Expression (N), Object_Entity);
3746 Set_Etype (Expression (N), Typ);
3748 -- Invariant, replace with obj
3751 Rewrite (N, Make_Identifier (Loc, Object_Name));
3752 Set_Entity (N, Object_Entity);
3755 end Replace_Type_Reference;
3757 -- Start of processing for Add_Invariants
3760 Ritem := First_Rep_Item (T);
3761 while Present (Ritem) loop
3762 if Nkind (Ritem) = N_Pragma
3763 and then Pragma_Name (Ritem) = Name_Invariant
3765 Arg1 := First (Pragma_Argument_Associations (Ritem));
3766 Arg2 := Next (Arg1);
3767 Arg3 := Next (Arg2);
3769 Arg1 := Get_Pragma_Arg (Arg1);
3770 Arg2 := Get_Pragma_Arg (Arg2);
3772 -- For Inherit case, ignore Invariant, process only Class case
3775 if not Class_Present (Ritem) then
3779 -- For Inherit false, process only item for right type
3782 if Entity (Arg1) /= Typ then
3788 Stmts := Empty_List;
3791 Exp := New_Copy_Tree (Arg2);
3794 -- We need to replace any occurrences of the name of the type
3795 -- with references to the object, converted to type'Class in
3796 -- the case of Invariant'Class aspects.
3798 Replace_Type_References (Exp, Chars (T));
3800 -- If this invariant comes from an aspect, find the aspect
3801 -- specification, and replace the saved expression because
3802 -- we need the subtype references replaced for the calls to
3803 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
3804 -- and Check_Aspect_At_End_Of_Declarations.
3806 if From_Aspect_Specification (Ritem) then
3811 -- Loop to find corresponding aspect, note that this
3812 -- must be present given the pragma is marked delayed.
3814 Aitem := Next_Rep_Item (Ritem);
3815 while Present (Aitem) loop
3816 if Nkind (Aitem) = N_Aspect_Specification
3817 and then Aspect_Rep_Item (Aitem) = Ritem
3820 (Identifier (Aitem), New_Copy_Tree (Exp));
3824 Aitem := Next_Rep_Item (Aitem);
3829 -- Now we need to preanalyze the expression to properly capture
3830 -- the visibility in the visible part. The expression will not
3831 -- be analyzed for real until the body is analyzed, but that is
3832 -- at the end of the private part and has the wrong visibility.
3834 Set_Parent (Exp, N);
3835 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
3837 -- Build first two arguments for Check pragma
3840 Make_Pragma_Argument_Association (Loc,
3841 Expression => Make_Identifier (Loc, Name_Invariant)),
3842 Make_Pragma_Argument_Association (Loc, Expression => Exp));
3844 -- Add message if present in Invariant pragma
3846 if Present (Arg3) then
3847 Str := Strval (Get_Pragma_Arg (Arg3));
3849 -- If inherited case, and message starts "failed invariant",
3850 -- change it to be "failed inherited invariant".
3853 String_To_Name_Buffer (Str);
3855 if Name_Buffer (1 .. 16) = "failed invariant" then
3856 Insert_Str_In_Name_Buffer ("inherited ", 8);
3857 Str := String_From_Name_Buffer;
3862 Make_Pragma_Argument_Association (Loc,
3863 Expression => Make_String_Literal (Loc, Str)));
3866 -- Add Check pragma to list of statements
3870 Pragma_Identifier =>
3871 Make_Identifier (Loc, Name_Check),
3872 Pragma_Argument_Associations => Assoc));
3874 -- If Inherited case and option enabled, output info msg. Note
3875 -- that we know this is a case of Invariant'Class.
3877 if Inherit and Opt.List_Inherited_Aspects then
3878 Error_Msg_Sloc := Sloc (Ritem);
3880 ("?info: & inherits `Invariant''Class` aspect from #",
3886 Next_Rep_Item (Ritem);
3890 -- Start of processing for Build_Invariant_Procedure
3896 Set_Etype (Object_Entity, Typ);
3898 -- Add invariants for the current type
3900 Add_Invariants (Typ, Inherit => False);
3902 -- Add invariants for parent types
3905 Current_Typ : Entity_Id;
3906 Parent_Typ : Entity_Id;
3911 Parent_Typ := Etype (Current_Typ);
3913 if Is_Private_Type (Parent_Typ)
3914 and then Present (Full_View (Base_Type (Parent_Typ)))
3916 Parent_Typ := Full_View (Base_Type (Parent_Typ));
3919 exit when Parent_Typ = Current_Typ;
3921 Current_Typ := Parent_Typ;
3922 Add_Invariants (Current_Typ, Inherit => True);
3926 -- Build the procedure if we generated at least one Check pragma
3928 if Stmts /= No_List then
3930 -- Build procedure declaration
3933 Make_Defining_Identifier (Loc,
3934 Chars => New_External_Name (Chars (Typ), "Invariant"));
3935 Set_Has_Invariants (SId);
3936 Set_Invariant_Procedure (Typ, SId);
3939 Make_Procedure_Specification (Loc,
3940 Defining_Unit_Name => SId,
3941 Parameter_Specifications => New_List (
3942 Make_Parameter_Specification (Loc,
3943 Defining_Identifier => Object_Entity,
3944 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3946 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
3948 -- Build procedure body
3951 Make_Defining_Identifier (Loc,
3952 Chars => New_External_Name (Chars (Typ), "Invariant"));
3955 Make_Procedure_Specification (Loc,
3956 Defining_Unit_Name => SId,
3957 Parameter_Specifications => New_List (
3958 Make_Parameter_Specification (Loc,
3959 Defining_Identifier =>
3960 Make_Defining_Identifier (Loc, Object_Name),
3961 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3964 Make_Subprogram_Body (Loc,
3965 Specification => Spec,
3966 Declarations => Empty_List,
3967 Handled_Statement_Sequence =>
3968 Make_Handled_Sequence_Of_Statements (Loc,
3969 Statements => Stmts));
3971 -- Insert procedure declaration and spec at the appropriate points.
3972 -- Skip this if there are no private declarations (that's an error
3973 -- that will be diagnosed elsewhere, and there is no point in having
3974 -- an invariant procedure set if the full declaration is missing).
3976 if Present (Private_Decls) then
3978 -- The spec goes at the end of visible declarations, but they have
3979 -- already been analyzed, so we need to explicitly do the analyze.
3981 Append_To (Visible_Decls, PDecl);
3984 -- The body goes at the end of the private declarations, which we
3985 -- have not analyzed yet, so we do not need to perform an explicit
3986 -- analyze call. We skip this if there are no private declarations
3987 -- (this is an error that will be caught elsewhere);
3989 Append_To (Private_Decls, PBody);
3992 end Build_Invariant_Procedure;
3994 ------------------------------
3995 -- Build_Predicate_Function --
3996 ------------------------------
3998 -- The procedure that is constructed here has the form
4000 -- function typPredicate (Ixxx : typ) return Boolean is
4003 -- exp1 and then exp2 and then ...
4004 -- and then typ1Predicate (typ1 (Ixxx))
4005 -- and then typ2Predicate (typ2 (Ixxx))
4007 -- end typPredicate;
4009 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4010 -- this is the point at which these expressions get analyzed, providing the
4011 -- required delay, and typ1, typ2, are entities from which predicates are
4012 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4013 -- use this function even if checks are off, e.g. for membership tests.
4015 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4016 Loc : constant Source_Ptr := Sloc (Typ);
4023 -- This is the expression for the return statement in the function. It
4024 -- is build by connecting the component predicates with AND THEN.
4026 procedure Add_Call (T : Entity_Id);
4027 -- Includes a call to the predicate function for type T in Expr if T
4028 -- has predicates and Predicate_Function (T) is non-empty.
4030 procedure Add_Predicates;
4031 -- Appends expressions for any Predicate pragmas in the rep item chain
4032 -- Typ to Expr. Note that we look only at items for this exact entity.
4033 -- Inheritance of predicates for the parent type is done by calling the
4034 -- Predicate_Function of the parent type, using Add_Call above.
4036 Object_Name : constant Name_Id := New_Internal_Name ('I');
4037 -- Name for argument of Predicate procedure
4039 Object_Entity : constant Entity_Id :=
4040 Make_Defining_Identifier (Loc, Object_Name);
4041 -- The entity for the spec entity for the argument
4043 Dynamic_Predicate_Present : Boolean := False;
4044 -- Set True if a dynamic predicate is present, results in the entire
4045 -- predicate being considered dynamic even if it looks static
4047 Static_Predicate_Present : Node_Id := Empty;
4048 -- Set to N_Pragma node for a static predicate if one is encountered.
4054 procedure Add_Call (T : Entity_Id) is
4058 if Present (T) and then Present (Predicate_Function (T)) then
4059 Set_Has_Predicates (Typ);
4061 -- Build the call to the predicate function of T
4065 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4067 -- Add call to evolving expression, using AND THEN if needed
4074 Left_Opnd => Relocate_Node (Expr),
4078 -- Output info message on inheritance if required. Note we do not
4079 -- give this information for generic actual types, since it is
4080 -- unwelcome noise in that case in instantiations. We also
4081 -- generally suppress the message in instantiations, and also
4082 -- if it involves internal names.
4084 if Opt.List_Inherited_Aspects
4085 and then not Is_Generic_Actual_Type (Typ)
4086 and then Instantiation_Depth (Sloc (Typ)) = 0
4087 and then not Is_Internal_Name (Chars (T))
4088 and then not Is_Internal_Name (Chars (Typ))
4090 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4091 Error_Msg_Node_2 := T;
4092 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4097 --------------------
4098 -- Add_Predicates --
4099 --------------------
4101 procedure Add_Predicates is
4106 procedure Replace_Type_Reference (N : Node_Id);
4107 -- Replace a single occurrence N of the subtype name with a reference
4108 -- to the formal of the predicate function. N can be an identifier
4109 -- referencing the subtype, or a selected component, representing an
4110 -- appropriately qualified occurrence of the subtype name.
4112 procedure Replace_Type_References is
4113 new Replace_Type_References_Generic (Replace_Type_Reference);
4114 -- Traverse an expression changing every occurrence of an identifier
4115 -- whose name matches the name of the subtype with a reference to
4116 -- the formal parameter of the predicate function.
4118 ----------------------------
4119 -- Replace_Type_Reference --
4120 ----------------------------
4122 procedure Replace_Type_Reference (N : Node_Id) is
4124 Rewrite (N, Make_Identifier (Loc, Object_Name));
4125 Set_Entity (N, Object_Entity);
4127 end Replace_Type_Reference;
4129 -- Start of processing for Add_Predicates
4132 Ritem := First_Rep_Item (Typ);
4133 while Present (Ritem) loop
4134 if Nkind (Ritem) = N_Pragma
4135 and then Pragma_Name (Ritem) = Name_Predicate
4137 if From_Dynamic_Predicate (Ritem) then
4138 Dynamic_Predicate_Present := True;
4139 elsif From_Static_Predicate (Ritem) then
4140 Static_Predicate_Present := Ritem;
4143 -- Acquire arguments
4145 Arg1 := First (Pragma_Argument_Associations (Ritem));
4146 Arg2 := Next (Arg1);
4148 Arg1 := Get_Pragma_Arg (Arg1);
4149 Arg2 := Get_Pragma_Arg (Arg2);
4151 -- See if this predicate pragma is for the current type
4153 if Entity (Arg1) = Typ then
4155 -- We have a match, this entry is for our subtype
4157 -- We need to replace any occurrences of the name of the
4158 -- type with references to the object.
4160 Replace_Type_References (Arg2, Chars (Typ));
4162 -- If this predicate comes from an aspect, find the aspect
4163 -- specification, and replace the saved expression because
4164 -- we need the subtype references replaced for the calls to
4165 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4166 -- and Check_Aspect_At_End_Of_Declarations.
4168 if From_Aspect_Specification (Ritem) then
4173 -- Loop to find corresponding aspect, note that this
4174 -- must be present given the pragma is marked delayed.
4176 Aitem := Next_Rep_Item (Ritem);
4178 if Nkind (Aitem) = N_Aspect_Specification
4179 and then Aspect_Rep_Item (Aitem) = Ritem
4182 (Identifier (Aitem), New_Copy_Tree (Arg2));
4186 Aitem := Next_Rep_Item (Aitem);
4191 -- Now we can add the expression
4194 Expr := Relocate_Node (Arg2);
4196 -- There already was a predicate, so add to it
4201 Left_Opnd => Relocate_Node (Expr),
4202 Right_Opnd => Relocate_Node (Arg2));
4207 Next_Rep_Item (Ritem);
4211 -- Start of processing for Build_Predicate_Function
4214 -- Initialize for construction of statement list
4218 -- Return if already built or if type does not have predicates
4220 if not Has_Predicates (Typ)
4221 or else Present (Predicate_Function (Typ))
4226 -- Add Predicates for the current type
4230 -- Add predicates for ancestor if present
4233 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4235 if Present (Atyp) then
4240 -- If we have predicates, build the function
4242 if Present (Expr) then
4244 -- Build function declaration
4246 pragma Assert (Has_Predicates (Typ));
4248 Make_Defining_Identifier (Loc,
4249 Chars => New_External_Name (Chars (Typ), "Predicate"));
4250 Set_Has_Predicates (SId);
4251 Set_Predicate_Function (Typ, SId);
4254 Make_Function_Specification (Loc,
4255 Defining_Unit_Name => SId,
4256 Parameter_Specifications => New_List (
4257 Make_Parameter_Specification (Loc,
4258 Defining_Identifier => Object_Entity,
4259 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4260 Result_Definition =>
4261 New_Occurrence_Of (Standard_Boolean, Loc));
4263 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4265 -- Build function body
4268 Make_Defining_Identifier (Loc,
4269 Chars => New_External_Name (Chars (Typ), "Predicate"));
4272 Make_Function_Specification (Loc,
4273 Defining_Unit_Name => SId,
4274 Parameter_Specifications => New_List (
4275 Make_Parameter_Specification (Loc,
4276 Defining_Identifier =>
4277 Make_Defining_Identifier (Loc, Object_Name),
4279 New_Occurrence_Of (Typ, Loc))),
4280 Result_Definition =>
4281 New_Occurrence_Of (Standard_Boolean, Loc));
4284 Make_Subprogram_Body (Loc,
4285 Specification => Spec,
4286 Declarations => Empty_List,
4287 Handled_Statement_Sequence =>
4288 Make_Handled_Sequence_Of_Statements (Loc,
4289 Statements => New_List (
4290 Make_Simple_Return_Statement (Loc,
4291 Expression => Expr))));
4293 -- Insert declaration before freeze node and body after
4295 Insert_Before_And_Analyze (N, FDecl);
4296 Insert_After_And_Analyze (N, FBody);
4298 -- Deal with static predicate case
4300 if Ekind_In (Typ, E_Enumeration_Subtype,
4301 E_Modular_Integer_Subtype,
4302 E_Signed_Integer_Subtype)
4303 and then Is_Static_Subtype (Typ)
4304 and then not Dynamic_Predicate_Present
4306 Build_Static_Predicate (Typ, Expr, Object_Name);
4308 if Present (Static_Predicate_Present)
4309 and No (Static_Predicate (Typ))
4312 ("expression does not have required form for "
4313 & "static predicate",
4314 Next (First (Pragma_Argument_Associations
4315 (Static_Predicate_Present))));
4319 end Build_Predicate_Function;
4321 ----------------------------
4322 -- Build_Static_Predicate --
4323 ----------------------------
4325 procedure Build_Static_Predicate
4330 Loc : constant Source_Ptr := Sloc (Expr);
4332 Non_Static : exception;
4333 -- Raised if something non-static is found
4335 Btyp : constant Entity_Id := Base_Type (Typ);
4337 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4338 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4339 -- Low bound and high bound value of base type of Typ
4341 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4342 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4343 -- Low bound and high bound values of static subtype Typ
4348 -- One entry in a Rlist value, a single REnt (range entry) value
4349 -- denotes one range from Lo to Hi. To represent a single value
4350 -- range Lo = Hi = value.
4352 type RList is array (Nat range <>) of REnt;
4353 -- A list of ranges. The ranges are sorted in increasing order,
4354 -- and are disjoint (there is a gap of at least one value between
4355 -- each range in the table). A value is in the set of ranges in
4356 -- Rlist if it lies within one of these ranges
4358 False_Range : constant RList :=
4359 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4360 -- An empty set of ranges represents a range list that can never be
4361 -- satisfied, since there are no ranges in which the value could lie,
4362 -- so it does not lie in any of them. False_Range is a canonical value
4363 -- for this empty set, but general processing should test for an Rlist
4364 -- with length zero (see Is_False predicate), since other null ranges
4365 -- may appear which must be treated as False.
4367 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4368 -- Range representing True, value must be in the base range
4370 function "and" (Left, Right : RList) return RList;
4371 -- And's together two range lists, returning a range list. This is
4372 -- a set intersection operation.
4374 function "or" (Left, Right : RList) return RList;
4375 -- Or's together two range lists, returning a range list. This is a
4376 -- set union operation.
4378 function "not" (Right : RList) return RList;
4379 -- Returns complement of a given range list, i.e. a range list
4380 -- representing all the values in TLo .. THi that are not in the
4381 -- input operand Right.
4383 function Build_Val (V : Uint) return Node_Id;
4384 -- Return an analyzed N_Identifier node referencing this value, suitable
4385 -- for use as an entry in the Static_Predicate list. This node is typed
4386 -- with the base type.
4388 function Build_Range (Lo, Hi : Uint) return Node_Id;
4389 -- Return an analyzed N_Range node referencing this range, suitable
4390 -- for use as an entry in the Static_Predicate list. This node is typed
4391 -- with the base type.
4393 function Get_RList (Exp : Node_Id) return RList;
4394 -- This is a recursive routine that converts the given expression into
4395 -- a list of ranges, suitable for use in building the static predicate.
4397 function Is_False (R : RList) return Boolean;
4398 pragma Inline (Is_False);
4399 -- Returns True if the given range list is empty, and thus represents
4400 -- a False list of ranges that can never be satisfied.
4402 function Is_True (R : RList) return Boolean;
4403 -- Returns True if R trivially represents the True predicate by having
4404 -- a single range from BLo to BHi.
4406 function Is_Type_Ref (N : Node_Id) return Boolean;
4407 pragma Inline (Is_Type_Ref);
4408 -- Returns if True if N is a reference to the type for the predicate in
4409 -- the expression (i.e. if it is an identifier whose Chars field matches
4410 -- the Nam given in the call).
4412 function Lo_Val (N : Node_Id) return Uint;
4413 -- Given static expression or static range from a Static_Predicate list,
4414 -- gets expression value or low bound of range.
4416 function Hi_Val (N : Node_Id) return Uint;
4417 -- Given static expression or static range from a Static_Predicate list,
4418 -- gets expression value of high bound of range.
4420 function Membership_Entry (N : Node_Id) return RList;
4421 -- Given a single membership entry (range, value, or subtype), returns
4422 -- the corresponding range list. Raises Static_Error if not static.
4424 function Membership_Entries (N : Node_Id) return RList;
4425 -- Given an element on an alternatives list of a membership operation,
4426 -- returns the range list corresponding to this entry and all following
4427 -- entries (i.e. returns the "or" of this list of values).
4429 function Stat_Pred (Typ : Entity_Id) return RList;
4430 -- Given a type, if it has a static predicate, then return the predicate
4431 -- as a range list, otherwise raise Non_Static.
4437 function "and" (Left, Right : RList) return RList is
4439 -- First range of result
4441 SLeft : Nat := Left'First;
4442 -- Start of rest of left entries
4444 SRight : Nat := Right'First;
4445 -- Start of rest of right entries
4448 -- If either range is True, return the other
4450 if Is_True (Left) then
4452 elsif Is_True (Right) then
4456 -- If either range is False, return False
4458 if Is_False (Left) or else Is_False (Right) then
4462 -- Loop to remove entries at start that are disjoint, and thus
4463 -- just get discarded from the result entirely.
4466 -- If no operands left in either operand, result is false
4468 if SLeft > Left'Last or else SRight > Right'Last then
4471 -- Discard first left operand entry if disjoint with right
4473 elsif Left (SLeft).Hi < Right (SRight).Lo then
4476 -- Discard first right operand entry if disjoint with left
4478 elsif Right (SRight).Hi < Left (SLeft).Lo then
4479 SRight := SRight + 1;
4481 -- Otherwise we have an overlapping entry
4488 -- Now we have two non-null operands, and first entries overlap.
4489 -- The first entry in the result will be the overlapping part of
4490 -- these two entries.
4492 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
4493 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
4495 -- Now we can remove the entry that ended at a lower value, since
4496 -- its contribution is entirely contained in Fent.
4498 if Left (SLeft).Hi <= Right (SRight).Hi then
4501 SRight := SRight + 1;
4504 -- Compute result by concatenating this first entry with the "and"
4505 -- of the remaining parts of the left and right operands. Note that
4506 -- if either of these is empty, "and" will yield empty, so that we
4507 -- will end up with just Fent, which is what we want in that case.
4510 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
4517 function "not" (Right : RList) return RList is
4519 -- Return True if False range
4521 if Is_False (Right) then
4525 -- Return False if True range
4527 if Is_True (Right) then
4531 -- Here if not trivial case
4534 Result : RList (1 .. Right'Length + 1);
4535 -- May need one more entry for gap at beginning and end
4538 -- Number of entries stored in Result
4543 if Right (Right'First).Lo > TLo then
4545 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
4548 -- Gaps between ranges
4550 for J in Right'First .. Right'Last - 1 loop
4553 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
4558 if Right (Right'Last).Hi < THi then
4560 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
4563 return Result (1 .. Count);
4571 function "or" (Left, Right : RList) return RList is
4573 -- First range of result
4575 SLeft : Nat := Left'First;
4576 -- Start of rest of left entries
4578 SRight : Nat := Right'First;
4579 -- Start of rest of right entries
4582 -- If either range is True, return True
4584 if Is_True (Left) or else Is_True (Right) then
4588 -- If either range is False (empty), return the other
4590 if Is_False (Left) then
4592 elsif Is_False (Right) then
4596 -- Initialize result first entry from left or right operand
4597 -- depending on which starts with the lower range.
4599 if Left (SLeft).Lo < Right (SRight).Lo then
4600 FEnt := Left (SLeft);
4603 FEnt := Right (SRight);
4604 SRight := SRight + 1;
4607 -- This loop eats ranges from left and right operands that
4608 -- are contiguous with the first range we are gathering.
4611 -- Eat first entry in left operand if contiguous or
4612 -- overlapped by gathered first operand of result.
4614 if SLeft <= Left'Last
4615 and then Left (SLeft).Lo <= FEnt.Hi + 1
4617 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
4620 -- Eat first entry in right operand if contiguous or
4621 -- overlapped by gathered right operand of result.
4623 elsif SRight <= Right'Last
4624 and then Right (SRight).Lo <= FEnt.Hi + 1
4626 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
4627 SRight := SRight + 1;
4629 -- All done if no more entries to eat!
4636 -- Obtain result as the first entry we just computed, concatenated
4637 -- to the "or" of the remaining results (if one operand is empty,
4638 -- this will just concatenate with the other
4641 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
4648 function Build_Range (Lo, Hi : Uint) return Node_Id is
4652 return Build_Val (Hi);
4656 Low_Bound => Build_Val (Lo),
4657 High_Bound => Build_Val (Hi));
4658 Set_Etype (Result, Btyp);
4659 Set_Analyzed (Result);
4668 function Build_Val (V : Uint) return Node_Id is
4672 if Is_Enumeration_Type (Typ) then
4673 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
4675 Result := Make_Integer_Literal (Loc, V);
4678 Set_Etype (Result, Btyp);
4679 Set_Is_Static_Expression (Result);
4680 Set_Analyzed (Result);
4688 function Get_RList (Exp : Node_Id) return RList is
4693 -- Static expression can only be true or false
4695 if Is_OK_Static_Expression (Exp) then
4699 if Expr_Value (Exp) = 0 then
4706 -- Otherwise test node type
4714 when N_Op_And | N_And_Then =>
4715 return Get_RList (Left_Opnd (Exp))
4717 Get_RList (Right_Opnd (Exp));
4721 when N_Op_Or | N_Or_Else =>
4722 return Get_RList (Left_Opnd (Exp))
4724 Get_RList (Right_Opnd (Exp));
4729 return not Get_RList (Right_Opnd (Exp));
4731 -- Comparisons of type with static value
4733 when N_Op_Compare =>
4734 -- Type is left operand
4736 if Is_Type_Ref (Left_Opnd (Exp))
4737 and then Is_OK_Static_Expression (Right_Opnd (Exp))
4739 Val := Expr_Value (Right_Opnd (Exp));
4741 -- Typ is right operand
4743 elsif Is_Type_Ref (Right_Opnd (Exp))
4744 and then Is_OK_Static_Expression (Left_Opnd (Exp))
4746 Val := Expr_Value (Left_Opnd (Exp));
4748 -- Invert sense of comparison
4751 when N_Op_Gt => Op := N_Op_Lt;
4752 when N_Op_Lt => Op := N_Op_Gt;
4753 when N_Op_Ge => Op := N_Op_Le;
4754 when N_Op_Le => Op := N_Op_Ge;
4755 when others => null;
4758 -- Other cases are non-static
4764 -- Construct range according to comparison operation
4768 return RList'(1 => REnt'(Val, Val));
4771 return RList'(1 => REnt'(Val, BHi));
4774 return RList'(1 => REnt'(Val + 1, BHi));
4777 return RList'(1 => REnt'(BLo, Val));
4780 return RList'(1 => REnt'(BLo, Val - 1));
4783 return RList'(REnt'(BLo, Val - 1),
4784 REnt'(Val + 1, BHi));
4787 raise Program_Error;
4793 if not Is_Type_Ref (Left_Opnd (Exp)) then
4797 if Present (Right_Opnd (Exp)) then
4798 return Membership_Entry (Right_Opnd (Exp));
4800 return Membership_Entries (First (Alternatives (Exp)));
4803 -- Negative membership (NOT IN)
4806 if not Is_Type_Ref (Left_Opnd (Exp)) then
4810 if Present (Right_Opnd (Exp)) then
4811 return not Membership_Entry (Right_Opnd (Exp));
4813 return not Membership_Entries (First (Alternatives (Exp)));
4816 -- Function call, may be call to static predicate
4818 when N_Function_Call =>
4819 if Is_Entity_Name (Name (Exp)) then
4821 Ent : constant Entity_Id := Entity (Name (Exp));
4823 if Has_Predicates (Ent) then
4824 return Stat_Pred (Etype (First_Formal (Ent)));
4829 -- Other function call cases are non-static
4833 -- Qualified expression, dig out the expression
4835 when N_Qualified_Expression =>
4836 return Get_RList (Expression (Exp));
4841 return (Get_RList (Left_Opnd (Exp))
4842 and not Get_RList (Right_Opnd (Exp)))
4843 or (Get_RList (Right_Opnd (Exp))
4844 and not Get_RList (Left_Opnd (Exp)));
4846 -- Any other node type is non-static
4857 function Hi_Val (N : Node_Id) return Uint is
4859 if Is_Static_Expression (N) then
4860 return Expr_Value (N);
4862 pragma Assert (Nkind (N) = N_Range);
4863 return Expr_Value (High_Bound (N));
4871 function Is_False (R : RList) return Boolean is
4873 return R'Length = 0;
4880 function Is_True (R : RList) return Boolean is
4883 and then R (R'First).Lo = BLo
4884 and then R (R'First).Hi = BHi;
4891 function Is_Type_Ref (N : Node_Id) return Boolean is
4893 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
4900 function Lo_Val (N : Node_Id) return Uint is
4902 if Is_Static_Expression (N) then
4903 return Expr_Value (N);
4905 pragma Assert (Nkind (N) = N_Range);
4906 return Expr_Value (Low_Bound (N));
4910 ------------------------
4911 -- Membership_Entries --
4912 ------------------------
4914 function Membership_Entries (N : Node_Id) return RList is
4916 if No (Next (N)) then
4917 return Membership_Entry (N);
4919 return Membership_Entry (N) or Membership_Entries (Next (N));
4921 end Membership_Entries;
4923 ----------------------
4924 -- Membership_Entry --
4925 ----------------------
4927 function Membership_Entry (N : Node_Id) return RList is
4935 if Nkind (N) = N_Range then
4936 if not Is_Static_Expression (Low_Bound (N))
4938 not Is_Static_Expression (High_Bound (N))
4942 SLo := Expr_Value (Low_Bound (N));
4943 SHi := Expr_Value (High_Bound (N));
4944 return RList'(1 => REnt'(SLo, SHi));
4947 -- Static expression case
4949 elsif Is_Static_Expression (N) then
4950 Val := Expr_Value (N);
4951 return RList'(1 => REnt'(Val, Val));
4953 -- Identifier (other than static expression) case
4955 else pragma Assert (Nkind (N) = N_Identifier);
4959 if Is_Type (Entity (N)) then
4961 -- If type has predicates, process them
4963 if Has_Predicates (Entity (N)) then
4964 return Stat_Pred (Entity (N));
4966 -- For static subtype without predicates, get range
4968 elsif Is_Static_Subtype (Entity (N)) then
4969 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
4970 SHi := Expr_Value (Type_High_Bound (Entity (N)));
4971 return RList'(1 => REnt'(SLo, SHi));
4973 -- Any other type makes us non-static
4979 -- Any other kind of identifier in predicate (e.g. a non-static
4980 -- expression value) means this is not a static predicate.
4986 end Membership_Entry;
4992 function Stat_Pred (Typ : Entity_Id) return RList is
4994 -- Not static if type does not have static predicates
4996 if not Has_Predicates (Typ)
4997 or else No (Static_Predicate (Typ))
5002 -- Otherwise we convert the predicate list to a range list
5005 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5009 P := First (Static_Predicate (Typ));
5010 for J in Result'Range loop
5011 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5019 -- Start of processing for Build_Static_Predicate
5022 -- Now analyze the expression to see if it is a static predicate
5025 Ranges : constant RList := Get_RList (Expr);
5026 -- Range list from expression if it is static
5031 -- Convert range list into a form for the static predicate. In the
5032 -- Ranges array, we just have raw ranges, these must be converted
5033 -- to properly typed and analyzed static expressions or range nodes.
5035 -- Note: here we limit ranges to the ranges of the subtype, so that
5036 -- a predicate is always false for values outside the subtype. That
5037 -- seems fine, such values are invalid anyway, and considering them
5038 -- to fail the predicate seems allowed and friendly, and furthermore
5039 -- simplifies processing for case statements and loops.
5043 for J in Ranges'Range loop
5045 Lo : Uint := Ranges (J).Lo;
5046 Hi : Uint := Ranges (J).Hi;
5049 -- Ignore completely out of range entry
5051 if Hi < TLo or else Lo > THi then
5054 -- Otherwise process entry
5057 -- Adjust out of range value to subtype range
5067 -- Convert range into required form
5070 Append_To (Plist, Build_Val (Lo));
5072 Append_To (Plist, Build_Range (Lo, Hi));
5078 -- Processing was successful and all entries were static, so now we
5079 -- can store the result as the predicate list.
5081 Set_Static_Predicate (Typ, Plist);
5083 -- The processing for static predicates put the expression into
5084 -- canonical form as a series of ranges. It also eliminated
5085 -- duplicates and collapsed and combined ranges. We might as well
5086 -- replace the alternatives list of the right operand of the
5087 -- membership test with the static predicate list, which will
5088 -- usually be more efficient.
5091 New_Alts : constant List_Id := New_List;
5096 Old_Node := First (Plist);
5097 while Present (Old_Node) loop
5098 New_Node := New_Copy (Old_Node);
5100 if Nkind (New_Node) = N_Range then
5101 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5102 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5105 Append_To (New_Alts, New_Node);
5109 -- If empty list, replace by False
5111 if Is_Empty_List (New_Alts) then
5112 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5114 -- Else replace by set membership test
5119 Left_Opnd => Make_Identifier (Loc, Nam),
5120 Right_Opnd => Empty,
5121 Alternatives => New_Alts));
5123 -- Resolve new expression in function context
5125 Install_Formals (Predicate_Function (Typ));
5126 Push_Scope (Predicate_Function (Typ));
5127 Analyze_And_Resolve (Expr, Standard_Boolean);
5133 -- If non-static, return doing nothing
5138 end Build_Static_Predicate;
5140 -----------------------------------------
5141 -- Check_Aspect_At_End_Of_Declarations --
5142 -----------------------------------------
5144 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5145 Ent : constant Entity_Id := Entity (ASN);
5146 Ident : constant Node_Id := Identifier (ASN);
5148 Freeze_Expr : constant Node_Id := Expression (ASN);
5149 -- Preanalyzed expression from call to Check_Aspect_At_Freeze_Point
5151 End_Decl_Expr : constant Node_Id := Entity (Ident);
5152 -- Expression to be analyzed at end of declarations
5154 T : constant Entity_Id := Etype (Freeze_Expr);
5155 -- Type required for preanalyze call
5157 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5160 -- Set False if error
5162 -- On entry to this procedure, Entity (Ident) contains a copy of the
5163 -- original expression from the aspect, saved for this purpose, and
5164 -- but Expression (Ident) is a preanalyzed copy of the expression,
5165 -- preanalyzed just after the freeze point.
5168 -- Case of stream attributes, just have to compare entities
5170 if A_Id = Aspect_Input or else
5171 A_Id = Aspect_Output or else
5172 A_Id = Aspect_Read or else
5175 Analyze (End_Decl_Expr);
5176 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5181 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5182 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5185 -- Output error message if error
5189 ("visibility of aspect for& changes after freeze point",
5192 ("?info: & is frozen here, aspects evaluated at this point",
5193 Freeze_Node (Ent), Ent);
5195 end Check_Aspect_At_End_Of_Declarations;
5197 ----------------------------------
5198 -- Check_Aspect_At_Freeze_Point --
5199 ----------------------------------
5201 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5202 Ident : constant Node_Id := Identifier (ASN);
5203 -- Identifier (use Entity field to save expression)
5206 -- Type required for preanalyze call
5208 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5211 -- On entry to this procedure, Entity (Ident) contains a copy of the
5212 -- original expression from the aspect, saved for this purpose.
5214 -- On exit from this procedure Entity (Ident) is unchanged, still
5215 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5216 -- of the expression, preanalyzed just after the freeze point.
5218 -- Make a copy of the expression to be preanalyed
5220 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5222 -- Find type for preanalyze call
5226 -- No_Aspect should be impossible
5229 raise Program_Error;
5231 -- Library unit aspects should be impossible (never delayed)
5233 when Library_Unit_Aspects =>
5234 raise Program_Error;
5236 -- Aspects taking an optional boolean argument. Should be impossible
5237 -- since these are never delayed.
5239 when Boolean_Aspects =>
5240 raise Program_Error;
5242 -- Default_Value is resolved with the type entity in question
5244 when Aspect_Default_Value =>
5247 -- Default_Component_Value is resolved with the component type
5249 when Aspect_Default_Component_Value =>
5250 T := Component_Type (Entity (ASN));
5252 -- Aspects corresponding to attribute definition clauses
5254 when Aspect_Address =>
5255 T := RTE (RE_Address);
5257 when Aspect_Bit_Order =>
5258 T := RTE (RE_Bit_Order);
5260 when Aspect_External_Tag =>
5261 T := Standard_String;
5263 when Aspect_Storage_Pool =>
5264 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5268 Aspect_Component_Size |
5269 Aspect_Machine_Radix |
5270 Aspect_Object_Size |
5272 Aspect_Storage_Size |
5273 Aspect_Stream_Size |
5274 Aspect_Value_Size =>
5277 -- Stream attribute. Special case, the expression is just an entity
5278 -- that does not need any resolution, so just analyze.
5284 Analyze (Expression (ASN));
5287 -- Suppress/Unsupress/Warnings should never be delayed
5289 when Aspect_Suppress |
5292 raise Program_Error;
5294 -- Pre/Post/Invariant/Predicate take boolean expressions
5296 when Aspect_Dynamic_Predicate |
5299 Aspect_Precondition |
5301 Aspect_Postcondition |
5303 Aspect_Static_Predicate |
5304 Aspect_Type_Invariant =>
5305 T := Standard_Boolean;
5308 -- Do the preanalyze call
5310 Preanalyze_Spec_Expression (Expression (ASN), T);
5311 end Check_Aspect_At_Freeze_Point;
5313 -----------------------------------
5314 -- Check_Constant_Address_Clause --
5315 -----------------------------------
5317 procedure Check_Constant_Address_Clause
5321 procedure Check_At_Constant_Address (Nod : Node_Id);
5322 -- Checks that the given node N represents a name whose 'Address is
5323 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5324 -- address value is the same at the point of declaration of U_Ent and at
5325 -- the time of elaboration of the address clause.
5327 procedure Check_Expr_Constants (Nod : Node_Id);
5328 -- Checks that Nod meets the requirements for a constant address clause
5329 -- in the sense of the enclosing procedure.
5331 procedure Check_List_Constants (Lst : List_Id);
5332 -- Check that all elements of list Lst meet the requirements for a
5333 -- constant address clause in the sense of the enclosing procedure.
5335 -------------------------------
5336 -- Check_At_Constant_Address --
5337 -------------------------------
5339 procedure Check_At_Constant_Address (Nod : Node_Id) is
5341 if Is_Entity_Name (Nod) then
5342 if Present (Address_Clause (Entity ((Nod)))) then
5344 ("invalid address clause for initialized object &!",
5347 ("address for& cannot" &
5348 " depend on another address clause! (RM 13.1(22))!",
5351 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
5352 and then Sloc (U_Ent) < Sloc (Entity (Nod))
5355 ("invalid address clause for initialized object &!",
5357 Error_Msg_Node_2 := U_Ent;
5359 ("\& must be defined before & (RM 13.1(22))!",
5363 elsif Nkind (Nod) = N_Selected_Component then
5365 T : constant Entity_Id := Etype (Prefix (Nod));
5368 if (Is_Record_Type (T)
5369 and then Has_Discriminants (T))
5372 and then Is_Record_Type (Designated_Type (T))
5373 and then Has_Discriminants (Designated_Type (T)))
5376 ("invalid address clause for initialized object &!",
5379 ("\address cannot depend on component" &
5380 " of discriminated record (RM 13.1(22))!",
5383 Check_At_Constant_Address (Prefix (Nod));
5387 elsif Nkind (Nod) = N_Indexed_Component then
5388 Check_At_Constant_Address (Prefix (Nod));
5389 Check_List_Constants (Expressions (Nod));
5392 Check_Expr_Constants (Nod);
5394 end Check_At_Constant_Address;
5396 --------------------------
5397 -- Check_Expr_Constants --
5398 --------------------------
5400 procedure Check_Expr_Constants (Nod : Node_Id) is
5401 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
5402 Ent : Entity_Id := Empty;
5405 if Nkind (Nod) in N_Has_Etype
5406 and then Etype (Nod) = Any_Type
5412 when N_Empty | N_Error =>
5415 when N_Identifier | N_Expanded_Name =>
5416 Ent := Entity (Nod);
5418 -- We need to look at the original node if it is different
5419 -- from the node, since we may have rewritten things and
5420 -- substituted an identifier representing the rewrite.
5422 if Original_Node (Nod) /= Nod then
5423 Check_Expr_Constants (Original_Node (Nod));
5425 -- If the node is an object declaration without initial
5426 -- value, some code has been expanded, and the expression
5427 -- is not constant, even if the constituents might be
5428 -- acceptable, as in A'Address + offset.
5430 if Ekind (Ent) = E_Variable
5432 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
5434 No (Expression (Declaration_Node (Ent)))
5437 ("invalid address clause for initialized object &!",
5440 -- If entity is constant, it may be the result of expanding
5441 -- a check. We must verify that its declaration appears
5442 -- before the object in question, else we also reject the
5445 elsif Ekind (Ent) = E_Constant
5446 and then In_Same_Source_Unit (Ent, U_Ent)
5447 and then Sloc (Ent) > Loc_U_Ent
5450 ("invalid address clause for initialized object &!",
5457 -- Otherwise look at the identifier and see if it is OK
5459 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
5460 or else Is_Type (Ent)
5465 Ekind (Ent) = E_Constant
5467 Ekind (Ent) = E_In_Parameter
5469 -- This is the case where we must have Ent defined before
5470 -- U_Ent. Clearly if they are in different units this
5471 -- requirement is met since the unit containing Ent is
5472 -- already processed.
5474 if not In_Same_Source_Unit (Ent, U_Ent) then
5477 -- Otherwise location of Ent must be before the location
5478 -- of U_Ent, that's what prior defined means.
5480 elsif Sloc (Ent) < Loc_U_Ent then
5485 ("invalid address clause for initialized object &!",
5487 Error_Msg_Node_2 := U_Ent;
5489 ("\& must be defined before & (RM 13.1(22))!",
5493 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
5494 Check_Expr_Constants (Original_Node (Nod));
5498 ("invalid address clause for initialized object &!",
5501 if Comes_From_Source (Ent) then
5503 ("\reference to variable& not allowed"
5504 & " (RM 13.1(22))!", Nod, Ent);
5507 ("non-static expression not allowed"
5508 & " (RM 13.1(22))!", Nod);
5512 when N_Integer_Literal =>
5514 -- If this is a rewritten unchecked conversion, in a system
5515 -- where Address is an integer type, always use the base type
5516 -- for a literal value. This is user-friendly and prevents
5517 -- order-of-elaboration issues with instances of unchecked
5520 if Nkind (Original_Node (Nod)) = N_Function_Call then
5521 Set_Etype (Nod, Base_Type (Etype (Nod)));
5524 when N_Real_Literal |
5526 N_Character_Literal =>
5530 Check_Expr_Constants (Low_Bound (Nod));
5531 Check_Expr_Constants (High_Bound (Nod));
5533 when N_Explicit_Dereference =>
5534 Check_Expr_Constants (Prefix (Nod));
5536 when N_Indexed_Component =>
5537 Check_Expr_Constants (Prefix (Nod));
5538 Check_List_Constants (Expressions (Nod));
5541 Check_Expr_Constants (Prefix (Nod));
5542 Check_Expr_Constants (Discrete_Range (Nod));
5544 when N_Selected_Component =>
5545 Check_Expr_Constants (Prefix (Nod));
5547 when N_Attribute_Reference =>
5548 if Attribute_Name (Nod) = Name_Address
5550 Attribute_Name (Nod) = Name_Access
5552 Attribute_Name (Nod) = Name_Unchecked_Access
5554 Attribute_Name (Nod) = Name_Unrestricted_Access
5556 Check_At_Constant_Address (Prefix (Nod));
5559 Check_Expr_Constants (Prefix (Nod));
5560 Check_List_Constants (Expressions (Nod));
5564 Check_List_Constants (Component_Associations (Nod));
5565 Check_List_Constants (Expressions (Nod));
5567 when N_Component_Association =>
5568 Check_Expr_Constants (Expression (Nod));
5570 when N_Extension_Aggregate =>
5571 Check_Expr_Constants (Ancestor_Part (Nod));
5572 Check_List_Constants (Component_Associations (Nod));
5573 Check_List_Constants (Expressions (Nod));
5578 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
5579 Check_Expr_Constants (Left_Opnd (Nod));
5580 Check_Expr_Constants (Right_Opnd (Nod));
5583 Check_Expr_Constants (Right_Opnd (Nod));
5585 when N_Type_Conversion |
5586 N_Qualified_Expression |
5588 Check_Expr_Constants (Expression (Nod));
5590 when N_Unchecked_Type_Conversion =>
5591 Check_Expr_Constants (Expression (Nod));
5593 -- If this is a rewritten unchecked conversion, subtypes in
5594 -- this node are those created within the instance. To avoid
5595 -- order of elaboration issues, replace them with their base
5596 -- types. Note that address clauses can cause order of
5597 -- elaboration problems because they are elaborated by the
5598 -- back-end at the point of definition, and may mention
5599 -- entities declared in between (as long as everything is
5600 -- static). It is user-friendly to allow unchecked conversions
5603 if Nkind (Original_Node (Nod)) = N_Function_Call then
5604 Set_Etype (Expression (Nod),
5605 Base_Type (Etype (Expression (Nod))));
5606 Set_Etype (Nod, Base_Type (Etype (Nod)));
5609 when N_Function_Call =>
5610 if not Is_Pure (Entity (Name (Nod))) then
5612 ("invalid address clause for initialized object &!",
5616 ("\function & is not pure (RM 13.1(22))!",
5617 Nod, Entity (Name (Nod)));
5620 Check_List_Constants (Parameter_Associations (Nod));
5623 when N_Parameter_Association =>
5624 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
5628 ("invalid address clause for initialized object &!",
5631 ("\must be constant defined before& (RM 13.1(22))!",
5634 end Check_Expr_Constants;
5636 --------------------------
5637 -- Check_List_Constants --
5638 --------------------------
5640 procedure Check_List_Constants (Lst : List_Id) is
5644 if Present (Lst) then
5645 Nod1 := First (Lst);
5646 while Present (Nod1) loop
5647 Check_Expr_Constants (Nod1);
5651 end Check_List_Constants;
5653 -- Start of processing for Check_Constant_Address_Clause
5656 -- If rep_clauses are to be ignored, no need for legality checks. In
5657 -- particular, no need to pester user about rep clauses that violate
5658 -- the rule on constant addresses, given that these clauses will be
5659 -- removed by Freeze before they reach the back end.
5661 if not Ignore_Rep_Clauses then
5662 Check_Expr_Constants (Expr);
5664 end Check_Constant_Address_Clause;
5666 ----------------------------------------
5667 -- Check_Record_Representation_Clause --
5668 ----------------------------------------
5670 procedure Check_Record_Representation_Clause (N : Node_Id) is
5671 Loc : constant Source_Ptr := Sloc (N);
5672 Ident : constant Node_Id := Identifier (N);
5673 Rectype : Entity_Id;
5678 Hbit : Uint := Uint_0;
5682 Max_Bit_So_Far : Uint;
5683 -- Records the maximum bit position so far. If all field positions
5684 -- are monotonically increasing, then we can skip the circuit for
5685 -- checking for overlap, since no overlap is possible.
5687 Tagged_Parent : Entity_Id := Empty;
5688 -- This is set in the case of a derived tagged type for which we have
5689 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
5690 -- positioned by record representation clauses). In this case we must
5691 -- check for overlap between components of this tagged type, and the
5692 -- components of its parent. Tagged_Parent will point to this parent
5693 -- type. For all other cases Tagged_Parent is left set to Empty.
5695 Parent_Last_Bit : Uint;
5696 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
5697 -- last bit position for any field in the parent type. We only need to
5698 -- check overlap for fields starting below this point.
5700 Overlap_Check_Required : Boolean;
5701 -- Used to keep track of whether or not an overlap check is required
5703 Overlap_Detected : Boolean := False;
5704 -- Set True if an overlap is detected
5706 Ccount : Natural := 0;
5707 -- Number of component clauses in record rep clause
5709 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
5710 -- Given two entities for record components or discriminants, checks
5711 -- if they have overlapping component clauses and issues errors if so.
5713 procedure Find_Component;
5714 -- Finds component entity corresponding to current component clause (in
5715 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
5716 -- start/stop bits for the field. If there is no matching component or
5717 -- if the matching component does not have a component clause, then
5718 -- that's an error and Comp is set to Empty, but no error message is
5719 -- issued, since the message was already given. Comp is also set to
5720 -- Empty if the current "component clause" is in fact a pragma.
5722 -----------------------------
5723 -- Check_Component_Overlap --
5724 -----------------------------
5726 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
5727 CC1 : constant Node_Id := Component_Clause (C1_Ent);
5728 CC2 : constant Node_Id := Component_Clause (C2_Ent);
5731 if Present (CC1) and then Present (CC2) then
5733 -- Exclude odd case where we have two tag fields in the same
5734 -- record, both at location zero. This seems a bit strange, but
5735 -- it seems to happen in some circumstances, perhaps on an error.
5737 if Chars (C1_Ent) = Name_uTag
5739 Chars (C2_Ent) = Name_uTag
5744 -- Here we check if the two fields overlap
5747 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
5748 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
5749 E1 : constant Uint := S1 + Esize (C1_Ent);
5750 E2 : constant Uint := S2 + Esize (C2_Ent);
5753 if E2 <= S1 or else E1 <= S2 then
5756 Error_Msg_Node_2 := Component_Name (CC2);
5757 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
5758 Error_Msg_Node_1 := Component_Name (CC1);
5760 ("component& overlaps & #", Component_Name (CC1));
5761 Overlap_Detected := True;
5765 end Check_Component_Overlap;
5767 --------------------
5768 -- Find_Component --
5769 --------------------
5771 procedure Find_Component is
5773 procedure Search_Component (R : Entity_Id);
5774 -- Search components of R for a match. If found, Comp is set.
5776 ----------------------
5777 -- Search_Component --
5778 ----------------------
5780 procedure Search_Component (R : Entity_Id) is
5782 Comp := First_Component_Or_Discriminant (R);
5783 while Present (Comp) loop
5785 -- Ignore error of attribute name for component name (we
5786 -- already gave an error message for this, so no need to
5789 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
5792 exit when Chars (Comp) = Chars (Component_Name (CC));
5795 Next_Component_Or_Discriminant (Comp);
5797 end Search_Component;
5799 -- Start of processing for Find_Component
5802 -- Return with Comp set to Empty if we have a pragma
5804 if Nkind (CC) = N_Pragma then
5809 -- Search current record for matching component
5811 Search_Component (Rectype);
5813 -- If not found, maybe component of base type that is absent from
5814 -- statically constrained first subtype.
5817 Search_Component (Base_Type (Rectype));
5820 -- If no component, or the component does not reference the component
5821 -- clause in question, then there was some previous error for which
5822 -- we already gave a message, so just return with Comp Empty.
5825 or else Component_Clause (Comp) /= CC
5829 -- Normal case where we have a component clause
5832 Fbit := Component_Bit_Offset (Comp);
5833 Lbit := Fbit + Esize (Comp) - 1;
5837 -- Start of processing for Check_Record_Representation_Clause
5841 Rectype := Entity (Ident);
5843 if Rectype = Any_Type then
5846 Rectype := Underlying_Type (Rectype);
5849 -- See if we have a fully repped derived tagged type
5852 PS : constant Entity_Id := Parent_Subtype (Rectype);
5855 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
5856 Tagged_Parent := PS;
5858 -- Find maximum bit of any component of the parent type
5860 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
5861 Pcomp := First_Entity (Tagged_Parent);
5862 while Present (Pcomp) loop
5863 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
5864 if Component_Bit_Offset (Pcomp) /= No_Uint
5865 and then Known_Static_Esize (Pcomp)
5870 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
5873 Next_Entity (Pcomp);
5879 -- All done if no component clauses
5881 CC := First (Component_Clauses (N));
5887 -- If a tag is present, then create a component clause that places it
5888 -- at the start of the record (otherwise gigi may place it after other
5889 -- fields that have rep clauses).
5891 Fent := First_Entity (Rectype);
5893 if Nkind (Fent) = N_Defining_Identifier
5894 and then Chars (Fent) = Name_uTag
5896 Set_Component_Bit_Offset (Fent, Uint_0);
5897 Set_Normalized_Position (Fent, Uint_0);
5898 Set_Normalized_First_Bit (Fent, Uint_0);
5899 Set_Normalized_Position_Max (Fent, Uint_0);
5900 Init_Esize (Fent, System_Address_Size);
5902 Set_Component_Clause (Fent,
5903 Make_Component_Clause (Loc,
5904 Component_Name => Make_Identifier (Loc, Name_uTag),
5906 Position => Make_Integer_Literal (Loc, Uint_0),
5907 First_Bit => Make_Integer_Literal (Loc, Uint_0),
5909 Make_Integer_Literal (Loc,
5910 UI_From_Int (System_Address_Size))));
5912 Ccount := Ccount + 1;
5915 Max_Bit_So_Far := Uint_Minus_1;
5916 Overlap_Check_Required := False;
5918 -- Process the component clauses
5920 while Present (CC) loop
5923 if Present (Comp) then
5924 Ccount := Ccount + 1;
5926 -- We need a full overlap check if record positions non-monotonic
5928 if Fbit <= Max_Bit_So_Far then
5929 Overlap_Check_Required := True;
5932 Max_Bit_So_Far := Lbit;
5934 -- Check bit position out of range of specified size
5936 if Has_Size_Clause (Rectype)
5937 and then Esize (Rectype) <= Lbit
5940 ("bit number out of range of specified size",
5943 -- Check for overlap with tag field
5946 if Is_Tagged_Type (Rectype)
5947 and then Fbit < System_Address_Size
5950 ("component overlaps tag field of&",
5951 Component_Name (CC), Rectype);
5952 Overlap_Detected := True;
5960 -- Check parent overlap if component might overlap parent field
5962 if Present (Tagged_Parent)
5963 and then Fbit <= Parent_Last_Bit
5965 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
5966 while Present (Pcomp) loop
5967 if not Is_Tag (Pcomp)
5968 and then Chars (Pcomp) /= Name_uParent
5970 Check_Component_Overlap (Comp, Pcomp);
5973 Next_Component_Or_Discriminant (Pcomp);
5981 -- Now that we have processed all the component clauses, check for
5982 -- overlap. We have to leave this till last, since the components can
5983 -- appear in any arbitrary order in the representation clause.
5985 -- We do not need this check if all specified ranges were monotonic,
5986 -- as recorded by Overlap_Check_Required being False at this stage.
5988 -- This first section checks if there are any overlapping entries at
5989 -- all. It does this by sorting all entries and then seeing if there are
5990 -- any overlaps. If there are none, then that is decisive, but if there
5991 -- are overlaps, they may still be OK (they may result from fields in
5992 -- different variants).
5994 if Overlap_Check_Required then
5995 Overlap_Check1 : declare
5997 OC_Fbit : array (0 .. Ccount) of Uint;
5998 -- First-bit values for component clauses, the value is the offset
5999 -- of the first bit of the field from start of record. The zero
6000 -- entry is for use in sorting.
6002 OC_Lbit : array (0 .. Ccount) of Uint;
6003 -- Last-bit values for component clauses, the value is the offset
6004 -- of the last bit of the field from start of record. The zero
6005 -- entry is for use in sorting.
6007 OC_Count : Natural := 0;
6008 -- Count of entries in OC_Fbit and OC_Lbit
6010 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6011 -- Compare routine for Sort
6013 procedure OC_Move (From : Natural; To : Natural);
6014 -- Move routine for Sort
6016 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6022 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6024 return OC_Fbit (Op1) < OC_Fbit (Op2);
6031 procedure OC_Move (From : Natural; To : Natural) is
6033 OC_Fbit (To) := OC_Fbit (From);
6034 OC_Lbit (To) := OC_Lbit (From);
6037 -- Start of processing for Overlap_Check
6040 CC := First (Component_Clauses (N));
6041 while Present (CC) loop
6043 -- Exclude component clause already marked in error
6045 if not Error_Posted (CC) then
6048 if Present (Comp) then
6049 OC_Count := OC_Count + 1;
6050 OC_Fbit (OC_Count) := Fbit;
6051 OC_Lbit (OC_Count) := Lbit;
6058 Sorting.Sort (OC_Count);
6060 Overlap_Check_Required := False;
6061 for J in 1 .. OC_Count - 1 loop
6062 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6063 Overlap_Check_Required := True;
6070 -- If Overlap_Check_Required is still True, then we have to do the full
6071 -- scale overlap check, since we have at least two fields that do
6072 -- overlap, and we need to know if that is OK since they are in
6073 -- different variant, or whether we have a definite problem.
6075 if Overlap_Check_Required then
6076 Overlap_Check2 : declare
6077 C1_Ent, C2_Ent : Entity_Id;
6078 -- Entities of components being checked for overlap
6081 -- Component_List node whose Component_Items are being checked
6084 -- Component declaration for component being checked
6087 C1_Ent := First_Entity (Base_Type (Rectype));
6089 -- Loop through all components in record. For each component check
6090 -- for overlap with any of the preceding elements on the component
6091 -- list containing the component and also, if the component is in
6092 -- a variant, check against components outside the case structure.
6093 -- This latter test is repeated recursively up the variant tree.
6095 Main_Component_Loop : while Present (C1_Ent) loop
6096 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6097 goto Continue_Main_Component_Loop;
6100 -- Skip overlap check if entity has no declaration node. This
6101 -- happens with discriminants in constrained derived types.
6102 -- Possibly we are missing some checks as a result, but that
6103 -- does not seem terribly serious.
6105 if No (Declaration_Node (C1_Ent)) then
6106 goto Continue_Main_Component_Loop;
6109 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6111 -- Loop through component lists that need checking. Check the
6112 -- current component list and all lists in variants above us.
6114 Component_List_Loop : loop
6116 -- If derived type definition, go to full declaration
6117 -- If at outer level, check discriminants if there are any.
6119 if Nkind (Clist) = N_Derived_Type_Definition then
6120 Clist := Parent (Clist);
6123 -- Outer level of record definition, check discriminants
6125 if Nkind_In (Clist, N_Full_Type_Declaration,
6126 N_Private_Type_Declaration)
6128 if Has_Discriminants (Defining_Identifier (Clist)) then
6130 First_Discriminant (Defining_Identifier (Clist));
6131 while Present (C2_Ent) loop
6132 exit when C1_Ent = C2_Ent;
6133 Check_Component_Overlap (C1_Ent, C2_Ent);
6134 Next_Discriminant (C2_Ent);
6138 -- Record extension case
6140 elsif Nkind (Clist) = N_Derived_Type_Definition then
6143 -- Otherwise check one component list
6146 Citem := First (Component_Items (Clist));
6147 while Present (Citem) loop
6148 if Nkind (Citem) = N_Component_Declaration then
6149 C2_Ent := Defining_Identifier (Citem);
6150 exit when C1_Ent = C2_Ent;
6151 Check_Component_Overlap (C1_Ent, C2_Ent);
6158 -- Check for variants above us (the parent of the Clist can
6159 -- be a variant, in which case its parent is a variant part,
6160 -- and the parent of the variant part is a component list
6161 -- whose components must all be checked against the current
6162 -- component for overlap).
6164 if Nkind (Parent (Clist)) = N_Variant then
6165 Clist := Parent (Parent (Parent (Clist)));
6167 -- Check for possible discriminant part in record, this
6168 -- is treated essentially as another level in the
6169 -- recursion. For this case the parent of the component
6170 -- list is the record definition, and its parent is the
6171 -- full type declaration containing the discriminant
6174 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6175 Clist := Parent (Parent ((Clist)));
6177 -- If neither of these two cases, we are at the top of
6181 exit Component_List_Loop;
6183 end loop Component_List_Loop;
6185 <<Continue_Main_Component_Loop>>
6186 Next_Entity (C1_Ent);
6188 end loop Main_Component_Loop;
6192 -- The following circuit deals with warning on record holes (gaps). We
6193 -- skip this check if overlap was detected, since it makes sense for the
6194 -- programmer to fix this illegality before worrying about warnings.
6196 if not Overlap_Detected and Warn_On_Record_Holes then
6197 Record_Hole_Check : declare
6198 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6199 -- Full declaration of record type
6201 procedure Check_Component_List
6205 -- Check component list CL for holes. The starting bit should be
6206 -- Sbit. which is zero for the main record component list and set
6207 -- appropriately for recursive calls for variants. DS is set to
6208 -- a list of discriminant specifications to be included in the
6209 -- consideration of components. It is No_List if none to consider.
6211 --------------------------
6212 -- Check_Component_List --
6213 --------------------------
6215 procedure Check_Component_List
6223 Compl := Integer (List_Length (Component_Items (CL)));
6225 if DS /= No_List then
6226 Compl := Compl + Integer (List_Length (DS));
6230 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6231 -- Gather components (zero entry is for sort routine)
6233 Ncomps : Natural := 0;
6234 -- Number of entries stored in Comps (starting at Comps (1))
6237 -- One component item or discriminant specification
6240 -- Starting bit for next component
6248 function Lt (Op1, Op2 : Natural) return Boolean;
6249 -- Compare routine for Sort
6251 procedure Move (From : Natural; To : Natural);
6252 -- Move routine for Sort
6254 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6260 function Lt (Op1, Op2 : Natural) return Boolean is
6262 return Component_Bit_Offset (Comps (Op1))
6264 Component_Bit_Offset (Comps (Op2));
6271 procedure Move (From : Natural; To : Natural) is
6273 Comps (To) := Comps (From);
6277 -- Gather discriminants into Comp
6279 if DS /= No_List then
6280 Citem := First (DS);
6281 while Present (Citem) loop
6282 if Nkind (Citem) = N_Discriminant_Specification then
6284 Ent : constant Entity_Id :=
6285 Defining_Identifier (Citem);
6287 if Ekind (Ent) = E_Discriminant then
6288 Ncomps := Ncomps + 1;
6289 Comps (Ncomps) := Ent;
6298 -- Gather component entities into Comp
6300 Citem := First (Component_Items (CL));
6301 while Present (Citem) loop
6302 if Nkind (Citem) = N_Component_Declaration then
6303 Ncomps := Ncomps + 1;
6304 Comps (Ncomps) := Defining_Identifier (Citem);
6310 -- Now sort the component entities based on the first bit.
6311 -- Note we already know there are no overlapping components.
6313 Sorting.Sort (Ncomps);
6315 -- Loop through entries checking for holes
6318 for J in 1 .. Ncomps loop
6320 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6322 if Error_Msg_Uint_1 > 0 then
6324 ("?^-bit gap before component&",
6325 Component_Name (Component_Clause (CEnt)), CEnt);
6328 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
6331 -- Process variant parts recursively if present
6333 if Present (Variant_Part (CL)) then
6334 Variant := First (Variants (Variant_Part (CL)));
6335 while Present (Variant) loop
6336 Check_Component_List
6337 (Component_List (Variant), Nbit, No_List);
6342 end Check_Component_List;
6344 -- Start of processing for Record_Hole_Check
6351 if Is_Tagged_Type (Rectype) then
6352 Sbit := UI_From_Int (System_Address_Size);
6357 if Nkind (Decl) = N_Full_Type_Declaration
6358 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6360 Check_Component_List
6361 (Component_List (Type_Definition (Decl)),
6363 Discriminant_Specifications (Decl));
6366 end Record_Hole_Check;
6369 -- For records that have component clauses for all components, and whose
6370 -- size is less than or equal to 32, we need to know the size in the
6371 -- front end to activate possible packed array processing where the
6372 -- component type is a record.
6374 -- At this stage Hbit + 1 represents the first unused bit from all the
6375 -- component clauses processed, so if the component clauses are
6376 -- complete, then this is the length of the record.
6378 -- For records longer than System.Storage_Unit, and for those where not
6379 -- all components have component clauses, the back end determines the
6380 -- length (it may for example be appropriate to round up the size
6381 -- to some convenient boundary, based on alignment considerations, etc).
6383 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
6385 -- Nothing to do if at least one component has no component clause
6387 Comp := First_Component_Or_Discriminant (Rectype);
6388 while Present (Comp) loop
6389 exit when No (Component_Clause (Comp));
6390 Next_Component_Or_Discriminant (Comp);
6393 -- If we fall out of loop, all components have component clauses
6394 -- and so we can set the size to the maximum value.
6397 Set_RM_Size (Rectype, Hbit + 1);
6400 end Check_Record_Representation_Clause;
6406 procedure Check_Size
6410 Biased : out Boolean)
6412 UT : constant Entity_Id := Underlying_Type (T);
6418 -- Dismiss cases for generic types or types with previous errors
6421 or else UT = Any_Type
6422 or else Is_Generic_Type (UT)
6423 or else Is_Generic_Type (Root_Type (UT))
6427 -- Check case of bit packed array
6429 elsif Is_Array_Type (UT)
6430 and then Known_Static_Component_Size (UT)
6431 and then Is_Bit_Packed_Array (UT)
6439 Asiz := Component_Size (UT);
6440 Indx := First_Index (UT);
6442 Ityp := Etype (Indx);
6444 -- If non-static bound, then we are not in the business of
6445 -- trying to check the length, and indeed an error will be
6446 -- issued elsewhere, since sizes of non-static array types
6447 -- cannot be set implicitly or explicitly.
6449 if not Is_Static_Subtype (Ityp) then
6453 -- Otherwise accumulate next dimension
6455 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
6456 Expr_Value (Type_Low_Bound (Ityp)) +
6460 exit when No (Indx);
6466 Error_Msg_Uint_1 := Asiz;
6468 ("size for& too small, minimum allowed is ^", N, T);
6469 Set_Esize (T, Asiz);
6470 Set_RM_Size (T, Asiz);
6474 -- All other composite types are ignored
6476 elsif Is_Composite_Type (UT) then
6479 -- For fixed-point types, don't check minimum if type is not frozen,
6480 -- since we don't know all the characteristics of the type that can
6481 -- affect the size (e.g. a specified small) till freeze time.
6483 elsif Is_Fixed_Point_Type (UT)
6484 and then not Is_Frozen (UT)
6488 -- Cases for which a minimum check is required
6491 -- Ignore if specified size is correct for the type
6493 if Known_Esize (UT) and then Siz = Esize (UT) then
6497 -- Otherwise get minimum size
6499 M := UI_From_Int (Minimum_Size (UT));
6503 -- Size is less than minimum size, but one possibility remains
6504 -- that we can manage with the new size if we bias the type.
6506 M := UI_From_Int (Minimum_Size (UT, Biased => True));
6509 Error_Msg_Uint_1 := M;
6511 ("size for& too small, minimum allowed is ^", N, T);
6521 -------------------------
6522 -- Get_Alignment_Value --
6523 -------------------------
6525 function Get_Alignment_Value (Expr : Node_Id) return Uint is
6526 Align : constant Uint := Static_Integer (Expr);
6529 if Align = No_Uint then
6532 elsif Align <= 0 then
6533 Error_Msg_N ("alignment value must be positive", Expr);
6537 for J in Int range 0 .. 64 loop
6539 M : constant Uint := Uint_2 ** J;
6542 exit when M = Align;
6546 ("alignment value must be power of 2", Expr);
6554 end Get_Alignment_Value;
6560 procedure Initialize is
6562 Address_Clause_Checks.Init;
6563 Independence_Checks.Init;
6564 Unchecked_Conversions.Init;
6567 -------------------------
6568 -- Is_Operational_Item --
6569 -------------------------
6571 function Is_Operational_Item (N : Node_Id) return Boolean is
6573 if Nkind (N) /= N_Attribute_Definition_Clause then
6577 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
6579 return Id = Attribute_Input
6580 or else Id = Attribute_Output
6581 or else Id = Attribute_Read
6582 or else Id = Attribute_Write
6583 or else Id = Attribute_External_Tag;
6586 end Is_Operational_Item;
6592 function Minimum_Size
6594 Biased : Boolean := False) return Nat
6596 Lo : Uint := No_Uint;
6597 Hi : Uint := No_Uint;
6598 LoR : Ureal := No_Ureal;
6599 HiR : Ureal := No_Ureal;
6600 LoSet : Boolean := False;
6601 HiSet : Boolean := False;
6605 R_Typ : constant Entity_Id := Root_Type (T);
6608 -- If bad type, return 0
6610 if T = Any_Type then
6613 -- For generic types, just return zero. There cannot be any legitimate
6614 -- need to know such a size, but this routine may be called with a
6615 -- generic type as part of normal processing.
6617 elsif Is_Generic_Type (R_Typ)
6618 or else R_Typ = Any_Type
6622 -- Access types. Normally an access type cannot have a size smaller
6623 -- than the size of System.Address. The exception is on VMS, where
6624 -- we have short and long addresses, and it is possible for an access
6625 -- type to have a short address size (and thus be less than the size
6626 -- of System.Address itself). We simply skip the check for VMS, and
6627 -- leave it to the back end to do the check.
6629 elsif Is_Access_Type (T) then
6630 if OpenVMS_On_Target then
6633 return System_Address_Size;
6636 -- Floating-point types
6638 elsif Is_Floating_Point_Type (T) then
6639 return UI_To_Int (Esize (R_Typ));
6643 elsif Is_Discrete_Type (T) then
6645 -- The following loop is looking for the nearest compile time known
6646 -- bounds following the ancestor subtype chain. The idea is to find
6647 -- the most restrictive known bounds information.
6651 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6656 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
6657 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
6664 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
6665 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
6671 Ancest := Ancestor_Subtype (Ancest);
6674 Ancest := Base_Type (T);
6676 if Is_Generic_Type (Ancest) then
6682 -- Fixed-point types. We can't simply use Expr_Value to get the
6683 -- Corresponding_Integer_Value values of the bounds, since these do not
6684 -- get set till the type is frozen, and this routine can be called
6685 -- before the type is frozen. Similarly the test for bounds being static
6686 -- needs to include the case where we have unanalyzed real literals for
6689 elsif Is_Fixed_Point_Type (T) then
6691 -- The following loop is looking for the nearest compile time known
6692 -- bounds following the ancestor subtype chain. The idea is to find
6693 -- the most restrictive known bounds information.
6697 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6701 -- Note: In the following two tests for LoSet and HiSet, it may
6702 -- seem redundant to test for N_Real_Literal here since normally
6703 -- one would assume that the test for the value being known at
6704 -- compile time includes this case. However, there is a glitch.
6705 -- If the real literal comes from folding a non-static expression,
6706 -- then we don't consider any non- static expression to be known
6707 -- at compile time if we are in configurable run time mode (needed
6708 -- in some cases to give a clearer definition of what is and what
6709 -- is not accepted). So the test is indeed needed. Without it, we
6710 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
6713 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
6714 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
6716 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
6723 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
6724 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
6726 HiR := Expr_Value_R (Type_High_Bound (Ancest));
6732 Ancest := Ancestor_Subtype (Ancest);
6735 Ancest := Base_Type (T);
6737 if Is_Generic_Type (Ancest) then
6743 Lo := UR_To_Uint (LoR / Small_Value (T));
6744 Hi := UR_To_Uint (HiR / Small_Value (T));
6746 -- No other types allowed
6749 raise Program_Error;
6752 -- Fall through with Hi and Lo set. Deal with biased case
6755 and then not Is_Fixed_Point_Type (T)
6756 and then not (Is_Enumeration_Type (T)
6757 and then Has_Non_Standard_Rep (T)))
6758 or else Has_Biased_Representation (T)
6764 -- Signed case. Note that we consider types like range 1 .. -1 to be
6765 -- signed for the purpose of computing the size, since the bounds have
6766 -- to be accommodated in the base type.
6768 if Lo < 0 or else Hi < 0 then
6772 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
6773 -- Note that we accommodate the case where the bounds cross. This
6774 -- can happen either because of the way the bounds are declared
6775 -- or because of the algorithm in Freeze_Fixed_Point_Type.
6789 -- If both bounds are positive, make sure that both are represen-
6790 -- table in the case where the bounds are crossed. This can happen
6791 -- either because of the way the bounds are declared, or because of
6792 -- the algorithm in Freeze_Fixed_Point_Type.
6798 -- S = size, (can accommodate 0 .. (2**size - 1))
6801 while Hi >= Uint_2 ** S loop
6809 ---------------------------
6810 -- New_Stream_Subprogram --
6811 ---------------------------
6813 procedure New_Stream_Subprogram
6817 Nam : TSS_Name_Type)
6819 Loc : constant Source_Ptr := Sloc (N);
6820 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
6821 Subp_Id : Entity_Id;
6822 Subp_Decl : Node_Id;
6826 Defer_Declaration : constant Boolean :=
6827 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
6828 -- For a tagged type, there is a declaration for each stream attribute
6829 -- at the freeze point, and we must generate only a completion of this
6830 -- declaration. We do the same for private types, because the full view
6831 -- might be tagged. Otherwise we generate a declaration at the point of
6832 -- the attribute definition clause.
6834 function Build_Spec return Node_Id;
6835 -- Used for declaration and renaming declaration, so that this is
6836 -- treated as a renaming_as_body.
6842 function Build_Spec return Node_Id is
6843 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
6846 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
6849 Subp_Id := Make_Defining_Identifier (Loc, Sname);
6851 -- S : access Root_Stream_Type'Class
6853 Formals := New_List (
6854 Make_Parameter_Specification (Loc,
6855 Defining_Identifier =>
6856 Make_Defining_Identifier (Loc, Name_S),
6858 Make_Access_Definition (Loc,
6861 Designated_Type (Etype (F)), Loc))));
6863 if Nam = TSS_Stream_Input then
6864 Spec := Make_Function_Specification (Loc,
6865 Defining_Unit_Name => Subp_Id,
6866 Parameter_Specifications => Formals,
6867 Result_Definition => T_Ref);
6872 Make_Parameter_Specification (Loc,
6873 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
6874 Out_Present => Out_P,
6875 Parameter_Type => T_Ref));
6878 Make_Procedure_Specification (Loc,
6879 Defining_Unit_Name => Subp_Id,
6880 Parameter_Specifications => Formals);
6886 -- Start of processing for New_Stream_Subprogram
6889 F := First_Formal (Subp);
6891 if Ekind (Subp) = E_Procedure then
6892 Etyp := Etype (Next_Formal (F));
6894 Etyp := Etype (Subp);
6897 -- Prepare subprogram declaration and insert it as an action on the
6898 -- clause node. The visibility for this entity is used to test for
6899 -- visibility of the attribute definition clause (in the sense of
6900 -- 8.3(23) as amended by AI-195).
6902 if not Defer_Declaration then
6904 Make_Subprogram_Declaration (Loc,
6905 Specification => Build_Spec);
6907 -- For a tagged type, there is always a visible declaration for each
6908 -- stream TSS (it is a predefined primitive operation), and the
6909 -- completion of this declaration occurs at the freeze point, which is
6910 -- not always visible at places where the attribute definition clause is
6911 -- visible. So, we create a dummy entity here for the purpose of
6912 -- tracking the visibility of the attribute definition clause itself.
6916 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
6918 Make_Object_Declaration (Loc,
6919 Defining_Identifier => Subp_Id,
6920 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
6923 Insert_Action (N, Subp_Decl);
6924 Set_Entity (N, Subp_Id);
6927 Make_Subprogram_Renaming_Declaration (Loc,
6928 Specification => Build_Spec,
6929 Name => New_Reference_To (Subp, Loc));
6931 if Defer_Declaration then
6932 Set_TSS (Base_Type (Ent), Subp_Id);
6934 Insert_Action (N, Subp_Decl);
6935 Copy_TSS (Subp_Id, Base_Type (Ent));
6937 end New_Stream_Subprogram;
6939 ------------------------
6940 -- Rep_Item_Too_Early --
6941 ------------------------
6943 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
6945 -- Cannot apply non-operational rep items to generic types
6947 if Is_Operational_Item (N) then
6951 and then Is_Generic_Type (Root_Type (T))
6953 Error_Msg_N ("representation item not allowed for generic type", N);
6957 -- Otherwise check for incomplete type
6959 if Is_Incomplete_Or_Private_Type (T)
6960 and then No (Underlying_Type (T))
6963 ("representation item must be after full type declaration", N);
6966 -- If the type has incomplete components, a representation clause is
6967 -- illegal but stream attributes and Convention pragmas are correct.
6969 elsif Has_Private_Component (T) then
6970 if Nkind (N) = N_Pragma then
6974 ("representation item must appear after type is fully defined",
6981 end Rep_Item_Too_Early;
6983 -----------------------
6984 -- Rep_Item_Too_Late --
6985 -----------------------
6987 function Rep_Item_Too_Late
6990 FOnly : Boolean := False) return Boolean
6993 Parent_Type : Entity_Id;
6996 -- Output the too late message. Note that this is not considered a
6997 -- serious error, since the effect is simply that we ignore the
6998 -- representation clause in this case.
7004 procedure Too_Late is
7006 Error_Msg_N ("|representation item appears too late!", N);
7009 -- Start of processing for Rep_Item_Too_Late
7012 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7013 -- types, which may be frozen if they appear in a representation clause
7014 -- for a local type.
7017 and then not From_With_Type (T)
7020 S := First_Subtype (T);
7022 if Present (Freeze_Node (S)) then
7024 ("?no more representation items for }", Freeze_Node (S), S);
7029 -- Check for case of non-tagged derived type whose parent either has
7030 -- primitive operations, or is a by reference type (RM 13.1(10)).
7034 and then Is_Derived_Type (T)
7035 and then not Is_Tagged_Type (T)
7037 Parent_Type := Etype (Base_Type (T));
7039 if Has_Primitive_Operations (Parent_Type) then
7042 ("primitive operations already defined for&!", N, Parent_Type);
7045 elsif Is_By_Reference_Type (Parent_Type) then
7048 ("parent type & is a by reference type!", N, Parent_Type);
7053 -- No error, link item into head of chain of rep items for the entity,
7054 -- but avoid chaining if we have an overloadable entity, and the pragma
7055 -- is one that can apply to multiple overloaded entities.
7057 if Is_Overloadable (T)
7058 and then Nkind (N) = N_Pragma
7061 Pname : constant Name_Id := Pragma_Name (N);
7063 if Pname = Name_Convention or else
7064 Pname = Name_Import or else
7065 Pname = Name_Export or else
7066 Pname = Name_External or else
7067 Pname = Name_Interface
7074 Record_Rep_Item (T, N);
7076 end Rep_Item_Too_Late;
7078 -------------------------------------
7079 -- Replace_Type_References_Generic --
7080 -------------------------------------
7082 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7084 function Replace_Node (N : Node_Id) return Traverse_Result;
7085 -- Processes a single node in the traversal procedure below, checking
7086 -- if node N should be replaced, and if so, doing the replacement.
7088 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7089 -- This instantiation provides the body of Replace_Type_References
7095 function Replace_Node (N : Node_Id) return Traverse_Result is
7100 -- Case of identifier
7102 if Nkind (N) = N_Identifier then
7104 -- If not the type name, all done with this node
7106 if Chars (N) /= TName then
7109 -- Otherwise do the replacement and we are done with this node
7112 Replace_Type_Reference (N);
7116 -- Case of selected component (which is what a qualification
7117 -- looks like in the unanalyzed tree, which is what we have.
7119 elsif Nkind (N) = N_Selected_Component then
7121 -- If selector name is not our type, keeping going (we might
7122 -- still have an occurrence of the type in the prefix).
7124 if Nkind (Selector_Name (N)) /= N_Identifier
7125 or else Chars (Selector_Name (N)) /= TName
7129 -- Selector name is our type, check qualification
7132 -- Loop through scopes and prefixes, doing comparison
7137 -- Continue if no more scopes or scope with no name
7139 if No (S) or else Nkind (S) not in N_Has_Chars then
7143 -- Do replace if prefix is an identifier matching the
7144 -- scope that we are currently looking at.
7146 if Nkind (P) = N_Identifier
7147 and then Chars (P) = Chars (S)
7149 Replace_Type_Reference (N);
7153 -- Go check scope above us if prefix is itself of the
7154 -- form of a selected component, whose selector matches
7155 -- the scope we are currently looking at.
7157 if Nkind (P) = N_Selected_Component
7158 and then Nkind (Selector_Name (P)) = N_Identifier
7159 and then Chars (Selector_Name (P)) = Chars (S)
7164 -- For anything else, we don't have a match, so keep on
7165 -- going, there are still some weird cases where we may
7166 -- still have a replacement within the prefix.
7174 -- Continue for any other node kind
7182 Replace_Type_Refs (N);
7183 end Replace_Type_References_Generic;
7185 -------------------------
7186 -- Same_Representation --
7187 -------------------------
7189 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7190 T1 : constant Entity_Id := Underlying_Type (Typ1);
7191 T2 : constant Entity_Id := Underlying_Type (Typ2);
7194 -- A quick check, if base types are the same, then we definitely have
7195 -- the same representation, because the subtype specific representation
7196 -- attributes (Size and Alignment) do not affect representation from
7197 -- the point of view of this test.
7199 if Base_Type (T1) = Base_Type (T2) then
7202 elsif Is_Private_Type (Base_Type (T2))
7203 and then Base_Type (T1) = Full_View (Base_Type (T2))
7208 -- Tagged types never have differing representations
7210 if Is_Tagged_Type (T1) then
7214 -- Representations are definitely different if conventions differ
7216 if Convention (T1) /= Convention (T2) then
7220 -- Representations are different if component alignments differ
7222 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7224 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7225 and then Component_Alignment (T1) /= Component_Alignment (T2)
7230 -- For arrays, the only real issue is component size. If we know the
7231 -- component size for both arrays, and it is the same, then that's
7232 -- good enough to know we don't have a change of representation.
7234 if Is_Array_Type (T1) then
7235 if Known_Component_Size (T1)
7236 and then Known_Component_Size (T2)
7237 and then Component_Size (T1) = Component_Size (T2)
7243 -- Types definitely have same representation if neither has non-standard
7244 -- representation since default representations are always consistent.
7245 -- If only one has non-standard representation, and the other does not,
7246 -- then we consider that they do not have the same representation. They
7247 -- might, but there is no way of telling early enough.
7249 if Has_Non_Standard_Rep (T1) then
7250 if not Has_Non_Standard_Rep (T2) then
7254 return not Has_Non_Standard_Rep (T2);
7257 -- Here the two types both have non-standard representation, and we need
7258 -- to determine if they have the same non-standard representation.
7260 -- For arrays, we simply need to test if the component sizes are the
7261 -- same. Pragma Pack is reflected in modified component sizes, so this
7262 -- check also deals with pragma Pack.
7264 if Is_Array_Type (T1) then
7265 return Component_Size (T1) = Component_Size (T2);
7267 -- Tagged types always have the same representation, because it is not
7268 -- possible to specify different representations for common fields.
7270 elsif Is_Tagged_Type (T1) then
7273 -- Case of record types
7275 elsif Is_Record_Type (T1) then
7277 -- Packed status must conform
7279 if Is_Packed (T1) /= Is_Packed (T2) then
7282 -- Otherwise we must check components. Typ2 maybe a constrained
7283 -- subtype with fewer components, so we compare the components
7284 -- of the base types.
7287 Record_Case : declare
7288 CD1, CD2 : Entity_Id;
7290 function Same_Rep return Boolean;
7291 -- CD1 and CD2 are either components or discriminants. This
7292 -- function tests whether the two have the same representation
7298 function Same_Rep return Boolean is
7300 if No (Component_Clause (CD1)) then
7301 return No (Component_Clause (CD2));
7305 Present (Component_Clause (CD2))
7307 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7309 Esize (CD1) = Esize (CD2);
7313 -- Start of processing for Record_Case
7316 if Has_Discriminants (T1) then
7317 CD1 := First_Discriminant (T1);
7318 CD2 := First_Discriminant (T2);
7320 -- The number of discriminants may be different if the
7321 -- derived type has fewer (constrained by values). The
7322 -- invisible discriminants retain the representation of
7323 -- the original, so the discrepancy does not per se
7324 -- indicate a different representation.
7327 and then Present (CD2)
7329 if not Same_Rep then
7332 Next_Discriminant (CD1);
7333 Next_Discriminant (CD2);
7338 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
7339 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
7341 while Present (CD1) loop
7342 if not Same_Rep then
7345 Next_Component (CD1);
7346 Next_Component (CD2);
7354 -- For enumeration types, we must check each literal to see if the
7355 -- representation is the same. Note that we do not permit enumeration
7356 -- representation clauses for Character and Wide_Character, so these
7357 -- cases were already dealt with.
7359 elsif Is_Enumeration_Type (T1) then
7360 Enumeration_Case : declare
7364 L1 := First_Literal (T1);
7365 L2 := First_Literal (T2);
7367 while Present (L1) loop
7368 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
7378 end Enumeration_Case;
7380 -- Any other types have the same representation for these purposes
7385 end Same_Representation;
7391 procedure Set_Biased
7395 Biased : Boolean := True)
7399 Set_Has_Biased_Representation (E);
7401 if Warn_On_Biased_Representation then
7403 ("?" & Msg & " forces biased representation for&", N, E);
7408 --------------------
7409 -- Set_Enum_Esize --
7410 --------------------
7412 procedure Set_Enum_Esize (T : Entity_Id) is
7420 -- Find the minimum standard size (8,16,32,64) that fits
7422 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
7423 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
7426 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
7427 Sz := Standard_Character_Size; -- May be > 8 on some targets
7429 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
7432 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
7435 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
7440 if Hi < Uint_2**08 then
7441 Sz := Standard_Character_Size; -- May be > 8 on some targets
7443 elsif Hi < Uint_2**16 then
7446 elsif Hi < Uint_2**32 then
7449 else pragma Assert (Hi < Uint_2**63);
7454 -- That minimum is the proper size unless we have a foreign convention
7455 -- and the size required is 32 or less, in which case we bump the size
7456 -- up to 32. This is required for C and C++ and seems reasonable for
7457 -- all other foreign conventions.
7459 if Has_Foreign_Convention (T)
7460 and then Esize (T) < Standard_Integer_Size
7462 Init_Esize (T, Standard_Integer_Size);
7468 ------------------------------
7469 -- Validate_Address_Clauses --
7470 ------------------------------
7472 procedure Validate_Address_Clauses is
7474 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
7476 ACCR : Address_Clause_Check_Record
7477 renames Address_Clause_Checks.Table (J);
7488 -- Skip processing of this entry if warning already posted
7490 if not Address_Warning_Posted (ACCR.N) then
7492 Expr := Original_Node (Expression (ACCR.N));
7496 X_Alignment := Alignment (ACCR.X);
7497 Y_Alignment := Alignment (ACCR.Y);
7499 -- Similarly obtain sizes
7501 X_Size := Esize (ACCR.X);
7502 Y_Size := Esize (ACCR.Y);
7504 -- Check for large object overlaying smaller one
7507 and then X_Size > Uint_0
7508 and then X_Size > Y_Size
7511 ("?& overlays smaller object", ACCR.N, ACCR.X);
7513 ("\?program execution may be erroneous", ACCR.N);
7514 Error_Msg_Uint_1 := X_Size;
7516 ("\?size of & is ^", ACCR.N, ACCR.X);
7517 Error_Msg_Uint_1 := Y_Size;
7519 ("\?size of & is ^", ACCR.N, ACCR.Y);
7521 -- Check for inadequate alignment, both of the base object
7522 -- and of the offset, if any.
7524 -- Note: we do not check the alignment if we gave a size
7525 -- warning, since it would likely be redundant.
7527 elsif Y_Alignment /= Uint_0
7528 and then (Y_Alignment < X_Alignment
7531 Nkind (Expr) = N_Attribute_Reference
7533 Attribute_Name (Expr) = Name_Address
7535 Has_Compatible_Alignment
7536 (ACCR.X, Prefix (Expr))
7537 /= Known_Compatible))
7540 ("?specified address for& may be inconsistent "
7544 ("\?program execution may be erroneous (RM 13.3(27))",
7546 Error_Msg_Uint_1 := X_Alignment;
7548 ("\?alignment of & is ^",
7550 Error_Msg_Uint_1 := Y_Alignment;
7552 ("\?alignment of & is ^",
7554 if Y_Alignment >= X_Alignment then
7556 ("\?but offset is not multiple of alignment",
7563 end Validate_Address_Clauses;
7565 ---------------------------
7566 -- Validate_Independence --
7567 ---------------------------
7569 procedure Validate_Independence is
7570 SU : constant Uint := UI_From_Int (System_Storage_Unit);
7578 procedure Check_Array_Type (Atyp : Entity_Id);
7579 -- Checks if the array type Atyp has independent components, and
7580 -- if not, outputs an appropriate set of error messages.
7582 procedure No_Independence;
7583 -- Output message that independence cannot be guaranteed
7585 function OK_Component (C : Entity_Id) return Boolean;
7586 -- Checks one component to see if it is independently accessible, and
7587 -- if so yields True, otherwise yields False if independent access
7588 -- cannot be guaranteed. This is a conservative routine, it only
7589 -- returns True if it knows for sure, it returns False if it knows
7590 -- there is a problem, or it cannot be sure there is no problem.
7592 procedure Reason_Bad_Component (C : Entity_Id);
7593 -- Outputs continuation message if a reason can be determined for
7594 -- the component C being bad.
7596 ----------------------
7597 -- Check_Array_Type --
7598 ----------------------
7600 procedure Check_Array_Type (Atyp : Entity_Id) is
7601 Ctyp : constant Entity_Id := Component_Type (Atyp);
7604 -- OK if no alignment clause, no pack, and no component size
7606 if not Has_Component_Size_Clause (Atyp)
7607 and then not Has_Alignment_Clause (Atyp)
7608 and then not Is_Packed (Atyp)
7613 -- Check actual component size
7615 if not Known_Component_Size (Atyp)
7616 or else not (Addressable (Component_Size (Atyp))
7617 and then Component_Size (Atyp) < 64)
7618 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
7622 -- Bad component size, check reason
7624 if Has_Component_Size_Clause (Atyp) then
7626 Get_Attribute_Definition_Clause
7627 (Atyp, Attribute_Component_Size);
7630 Error_Msg_Sloc := Sloc (P);
7631 Error_Msg_N ("\because of Component_Size clause#", N);
7636 if Is_Packed (Atyp) then
7637 P := Get_Rep_Pragma (Atyp, Name_Pack);
7640 Error_Msg_Sloc := Sloc (P);
7641 Error_Msg_N ("\because of pragma Pack#", N);
7646 -- No reason found, just return
7651 -- Array type is OK independence-wise
7654 end Check_Array_Type;
7656 ---------------------
7657 -- No_Independence --
7658 ---------------------
7660 procedure No_Independence is
7662 if Pragma_Name (N) = Name_Independent then
7664 ("independence cannot be guaranteed for&", N, E);
7667 ("independent components cannot be guaranteed for&", N, E);
7669 end No_Independence;
7675 function OK_Component (C : Entity_Id) return Boolean is
7676 Rec : constant Entity_Id := Scope (C);
7677 Ctyp : constant Entity_Id := Etype (C);
7680 -- OK if no component clause, no Pack, and no alignment clause
7682 if No (Component_Clause (C))
7683 and then not Is_Packed (Rec)
7684 and then not Has_Alignment_Clause (Rec)
7689 -- Here we look at the actual component layout. A component is
7690 -- addressable if its size is a multiple of the Esize of the
7691 -- component type, and its starting position in the record has
7692 -- appropriate alignment, and the record itself has appropriate
7693 -- alignment to guarantee the component alignment.
7695 -- Make sure sizes are static, always assume the worst for any
7696 -- cases where we cannot check static values.
7698 if not (Known_Static_Esize (C)
7699 and then Known_Static_Esize (Ctyp))
7704 -- Size of component must be addressable or greater than 64 bits
7705 -- and a multiple of bytes.
7707 if not Addressable (Esize (C))
7708 and then Esize (C) < Uint_64
7713 -- Check size is proper multiple
7715 if Esize (C) mod Esize (Ctyp) /= 0 then
7719 -- Check alignment of component is OK
7721 if not Known_Component_Bit_Offset (C)
7722 or else Component_Bit_Offset (C) < Uint_0
7723 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
7728 -- Check alignment of record type is OK
7730 if not Known_Alignment (Rec)
7731 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7736 -- All tests passed, component is addressable
7741 --------------------------
7742 -- Reason_Bad_Component --
7743 --------------------------
7745 procedure Reason_Bad_Component (C : Entity_Id) is
7746 Rec : constant Entity_Id := Scope (C);
7747 Ctyp : constant Entity_Id := Etype (C);
7750 -- If component clause present assume that's the problem
7752 if Present (Component_Clause (C)) then
7753 Error_Msg_Sloc := Sloc (Component_Clause (C));
7754 Error_Msg_N ("\because of Component_Clause#", N);
7758 -- If pragma Pack clause present, assume that's the problem
7760 if Is_Packed (Rec) then
7761 P := Get_Rep_Pragma (Rec, Name_Pack);
7764 Error_Msg_Sloc := Sloc (P);
7765 Error_Msg_N ("\because of pragma Pack#", N);
7770 -- See if record has bad alignment clause
7772 if Has_Alignment_Clause (Rec)
7773 and then Known_Alignment (Rec)
7774 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7776 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
7779 Error_Msg_Sloc := Sloc (P);
7780 Error_Msg_N ("\because of Alignment clause#", N);
7784 -- Couldn't find a reason, so return without a message
7787 end Reason_Bad_Component;
7789 -- Start of processing for Validate_Independence
7792 for J in Independence_Checks.First .. Independence_Checks.Last loop
7793 N := Independence_Checks.Table (J).N;
7794 E := Independence_Checks.Table (J).E;
7795 IC := Pragma_Name (N) = Name_Independent_Components;
7797 -- Deal with component case
7799 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
7800 if not OK_Component (E) then
7802 Reason_Bad_Component (E);
7807 -- Deal with record with Independent_Components
7809 if IC and then Is_Record_Type (E) then
7810 Comp := First_Component_Or_Discriminant (E);
7811 while Present (Comp) loop
7812 if not OK_Component (Comp) then
7814 Reason_Bad_Component (Comp);
7818 Next_Component_Or_Discriminant (Comp);
7822 -- Deal with address clause case
7824 if Is_Object (E) then
7825 Addr := Address_Clause (E);
7827 if Present (Addr) then
7829 Error_Msg_Sloc := Sloc (Addr);
7830 Error_Msg_N ("\because of Address clause#", N);
7835 -- Deal with independent components for array type
7837 if IC and then Is_Array_Type (E) then
7838 Check_Array_Type (E);
7841 -- Deal with independent components for array object
7843 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
7844 Check_Array_Type (Etype (E));
7849 end Validate_Independence;
7851 -----------------------------------
7852 -- Validate_Unchecked_Conversion --
7853 -----------------------------------
7855 procedure Validate_Unchecked_Conversion
7857 Act_Unit : Entity_Id)
7864 -- Obtain source and target types. Note that we call Ancestor_Subtype
7865 -- here because the processing for generic instantiation always makes
7866 -- subtypes, and we want the original frozen actual types.
7868 -- If we are dealing with private types, then do the check on their
7869 -- fully declared counterparts if the full declarations have been
7870 -- encountered (they don't have to be visible, but they must exist!)
7872 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
7874 if Is_Private_Type (Source)
7875 and then Present (Underlying_Type (Source))
7877 Source := Underlying_Type (Source);
7880 Target := Ancestor_Subtype (Etype (Act_Unit));
7882 -- If either type is generic, the instantiation happens within a generic
7883 -- unit, and there is nothing to check. The proper check
7884 -- will happen when the enclosing generic is instantiated.
7886 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
7890 if Is_Private_Type (Target)
7891 and then Present (Underlying_Type (Target))
7893 Target := Underlying_Type (Target);
7896 -- Source may be unconstrained array, but not target
7898 if Is_Array_Type (Target)
7899 and then not Is_Constrained (Target)
7902 ("unchecked conversion to unconstrained array not allowed", N);
7906 -- Warn if conversion between two different convention pointers
7908 if Is_Access_Type (Target)
7909 and then Is_Access_Type (Source)
7910 and then Convention (Target) /= Convention (Source)
7911 and then Warn_On_Unchecked_Conversion
7913 -- Give warnings for subprogram pointers only on most targets. The
7914 -- exception is VMS, where data pointers can have different lengths
7915 -- depending on the pointer convention.
7917 if Is_Access_Subprogram_Type (Target)
7918 or else Is_Access_Subprogram_Type (Source)
7919 or else OpenVMS_On_Target
7922 ("?conversion between pointers with different conventions!", N);
7926 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
7927 -- warning when compiling GNAT-related sources.
7929 if Warn_On_Unchecked_Conversion
7930 and then not In_Predefined_Unit (N)
7931 and then RTU_Loaded (Ada_Calendar)
7933 (Chars (Source) = Name_Time
7935 Chars (Target) = Name_Time)
7937 -- If Ada.Calendar is loaded and the name of one of the operands is
7938 -- Time, there is a good chance that this is Ada.Calendar.Time.
7941 Calendar_Time : constant Entity_Id :=
7942 Full_View (RTE (RO_CA_Time));
7944 pragma Assert (Present (Calendar_Time));
7946 if Source = Calendar_Time
7947 or else Target = Calendar_Time
7950 ("?representation of 'Time values may change between " &
7951 "'G'N'A'T versions", N);
7956 -- Make entry in unchecked conversion table for later processing by
7957 -- Validate_Unchecked_Conversions, which will check sizes and alignments
7958 -- (using values set by the back-end where possible). This is only done
7959 -- if the appropriate warning is active.
7961 if Warn_On_Unchecked_Conversion then
7962 Unchecked_Conversions.Append
7963 (New_Val => UC_Entry'
7968 -- If both sizes are known statically now, then back end annotation
7969 -- is not required to do a proper check but if either size is not
7970 -- known statically, then we need the annotation.
7972 if Known_Static_RM_Size (Source)
7973 and then Known_Static_RM_Size (Target)
7977 Back_Annotate_Rep_Info := True;
7981 -- If unchecked conversion to access type, and access type is declared
7982 -- in the same unit as the unchecked conversion, then set the
7983 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
7986 if Is_Access_Type (Target) and then
7987 In_Same_Source_Unit (Target, N)
7989 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
7992 -- Generate N_Validate_Unchecked_Conversion node for back end in
7993 -- case the back end needs to perform special validation checks.
7995 -- Shouldn't this be in Exp_Ch13, since the check only gets done
7996 -- if we have full expansion and the back end is called ???
7999 Make_Validate_Unchecked_Conversion (Sloc (N));
8000 Set_Source_Type (Vnode, Source);
8001 Set_Target_Type (Vnode, Target);
8003 -- If the unchecked conversion node is in a list, just insert before it.
8004 -- If not we have some strange case, not worth bothering about.
8006 if Is_List_Member (N) then
8007 Insert_After (N, Vnode);
8009 end Validate_Unchecked_Conversion;
8011 ------------------------------------
8012 -- Validate_Unchecked_Conversions --
8013 ------------------------------------
8015 procedure Validate_Unchecked_Conversions is
8017 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8019 T : UC_Entry renames Unchecked_Conversions.Table (N);
8021 Eloc : constant Source_Ptr := T.Eloc;
8022 Source : constant Entity_Id := T.Source;
8023 Target : constant Entity_Id := T.Target;
8029 -- This validation check, which warns if we have unequal sizes for
8030 -- unchecked conversion, and thus potentially implementation
8031 -- dependent semantics, is one of the few occasions on which we
8032 -- use the official RM size instead of Esize. See description in
8033 -- Einfo "Handling of Type'Size Values" for details.
8035 if Serious_Errors_Detected = 0
8036 and then Known_Static_RM_Size (Source)
8037 and then Known_Static_RM_Size (Target)
8039 -- Don't do the check if warnings off for either type, note the
8040 -- deliberate use of OR here instead of OR ELSE to get the flag
8041 -- Warnings_Off_Used set for both types if appropriate.
8043 and then not (Has_Warnings_Off (Source)
8045 Has_Warnings_Off (Target))
8047 Source_Siz := RM_Size (Source);
8048 Target_Siz := RM_Size (Target);
8050 if Source_Siz /= Target_Siz then
8052 ("?types for unchecked conversion have different sizes!",
8055 if All_Errors_Mode then
8056 Error_Msg_Name_1 := Chars (Source);
8057 Error_Msg_Uint_1 := Source_Siz;
8058 Error_Msg_Name_2 := Chars (Target);
8059 Error_Msg_Uint_2 := Target_Siz;
8060 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8062 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8064 if Is_Discrete_Type (Source)
8065 and then Is_Discrete_Type (Target)
8067 if Source_Siz > Target_Siz then
8069 ("\?^ high order bits of source will be ignored!",
8072 elsif Is_Unsigned_Type (Source) then
8074 ("\?source will be extended with ^ high order " &
8075 "zero bits?!", Eloc);
8079 ("\?source will be extended with ^ high order " &
8084 elsif Source_Siz < Target_Siz then
8085 if Is_Discrete_Type (Target) then
8086 if Bytes_Big_Endian then
8088 ("\?target value will include ^ undefined " &
8093 ("\?target value will include ^ undefined " &
8100 ("\?^ trailing bits of target value will be " &
8101 "undefined!", Eloc);
8104 else pragma Assert (Source_Siz > Target_Siz);
8106 ("\?^ trailing bits of source will be ignored!",
8113 -- If both types are access types, we need to check the alignment.
8114 -- If the alignment of both is specified, we can do it here.
8116 if Serious_Errors_Detected = 0
8117 and then Ekind (Source) in Access_Kind
8118 and then Ekind (Target) in Access_Kind
8119 and then Target_Strict_Alignment
8120 and then Present (Designated_Type (Source))
8121 and then Present (Designated_Type (Target))
8124 D_Source : constant Entity_Id := Designated_Type (Source);
8125 D_Target : constant Entity_Id := Designated_Type (Target);
8128 if Known_Alignment (D_Source)
8129 and then Known_Alignment (D_Target)
8132 Source_Align : constant Uint := Alignment (D_Source);
8133 Target_Align : constant Uint := Alignment (D_Target);
8136 if Source_Align < Target_Align
8137 and then not Is_Tagged_Type (D_Source)
8139 -- Suppress warning if warnings suppressed on either
8140 -- type or either designated type. Note the use of
8141 -- OR here instead of OR ELSE. That is intentional,
8142 -- we would like to set flag Warnings_Off_Used in
8143 -- all types for which warnings are suppressed.
8145 and then not (Has_Warnings_Off (D_Source)
8147 Has_Warnings_Off (D_Target)
8149 Has_Warnings_Off (Source)
8151 Has_Warnings_Off (Target))
8153 Error_Msg_Uint_1 := Target_Align;
8154 Error_Msg_Uint_2 := Source_Align;
8155 Error_Msg_Node_1 := D_Target;
8156 Error_Msg_Node_2 := D_Source;
8158 ("?alignment of & (^) is stricter than " &
8159 "alignment of & (^)!", Eloc);
8161 ("\?resulting access value may have invalid " &
8162 "alignment!", Eloc);
8170 end Validate_Unchecked_Conversions;
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