1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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;
63 with Warnsw; use Warnsw;
65 with GNAT.Heap_Sort_G;
67 package body Sem_Ch13 is
69 SSU : constant Pos := System_Storage_Unit;
70 -- Convenient short hand for commonly used constant
72 -----------------------
73 -- Local Subprograms --
74 -----------------------
76 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint);
77 -- This routine is called after setting one of the sizes of type entity
78 -- Typ to Size. The purpose is to deal with the situation of a derived
79 -- type whose inherited alignment is no longer appropriate for the new
80 -- size value. In this case, we reset the Alignment to unknown.
82 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
83 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
84 -- then either there are pragma Invariant entries on the rep chain for the
85 -- type (note that Predicate aspects are converted to pragma Predicate), or
86 -- there are inherited aspects from a parent type, or ancestor subtypes.
87 -- This procedure builds the spec and body for the Predicate function that
88 -- tests these predicates. N is the freeze node for the type. The spec of
89 -- the function is inserted before the freeze node, and the body of the
90 -- function is inserted after the freeze node.
92 procedure Build_Static_Predicate
96 -- Given a predicated type Typ, where Typ is a discrete static subtype,
97 -- whose predicate expression is Expr, tests if Expr is a static predicate,
98 -- and if so, builds the predicate range list. Nam is the name of the one
99 -- argument to the predicate function. Occurrences of the type name in the
100 -- predicate expression have been replaced by identifier references to this
101 -- name, which is unique, so any identifier with Chars matching Nam must be
102 -- a reference to the type. If the predicate is non-static, this procedure
103 -- returns doing nothing. If the predicate is static, then the predicate
104 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
105 -- a canonicalized membership operation.
107 function Get_Alignment_Value (Expr : Node_Id) return Uint;
108 -- Given the expression for an alignment value, returns the corresponding
109 -- Uint value. If the value is inappropriate, then error messages are
110 -- posted as required, and a value of No_Uint is returned.
112 function Is_Operational_Item (N : Node_Id) return Boolean;
113 -- A specification for a stream attribute is allowed before the full type
114 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
115 -- that do not specify a representation characteristic are operational
118 procedure New_Stream_Subprogram
122 Nam : TSS_Name_Type);
123 -- Create a subprogram renaming of a given stream attribute to the
124 -- designated subprogram and then in the tagged case, provide this as a
125 -- primitive operation, or in the non-tagged case make an appropriate TSS
126 -- entry. This is more properly an expansion activity than just semantics,
127 -- but the presence of user-defined stream functions for limited types is a
128 -- legality check, which is why this takes place here rather than in
129 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
130 -- function to be generated.
132 -- To avoid elaboration anomalies with freeze nodes, for untagged types
133 -- we generate both a subprogram declaration and a subprogram renaming
134 -- declaration, so that the attribute specification is handled as a
135 -- renaming_as_body. For tagged types, the specification is one of the
139 with procedure Replace_Type_Reference (N : Node_Id);
140 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
141 -- This is used to scan an expression for a predicate or invariant aspect
142 -- replacing occurrences of the name TName (the name of the subtype to
143 -- which the aspect applies) with appropriate references to the parameter
144 -- of the predicate function or invariant procedure. The procedure passed
145 -- as a generic parameter does the actual replacement of node N, which is
146 -- either a simple direct reference to TName, or a selected component that
147 -- represents an appropriately qualified occurrence of TName.
153 Biased : Boolean := True);
154 -- If Biased is True, sets Has_Biased_Representation flag for E, and
155 -- outputs a warning message at node N if Warn_On_Biased_Representation is
156 -- is True. This warning inserts the string Msg to describe the construct
159 ----------------------------------------------
160 -- Table for Validate_Unchecked_Conversions --
161 ----------------------------------------------
163 -- The following table collects unchecked conversions for validation.
164 -- Entries are made by Validate_Unchecked_Conversion and then the
165 -- call to Validate_Unchecked_Conversions does the actual error
166 -- checking and posting of warnings. The reason for this delayed
167 -- processing is to take advantage of back-annotations of size and
168 -- alignment values performed by the back end.
170 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
171 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
172 -- will already have modified all Sloc values if the -gnatD option is set.
174 type UC_Entry is record
175 Eloc : Source_Ptr; -- node used for posting warnings
176 Source : Entity_Id; -- source type for unchecked conversion
177 Target : Entity_Id; -- target type for unchecked conversion
180 package Unchecked_Conversions is new Table.Table (
181 Table_Component_Type => UC_Entry,
182 Table_Index_Type => Int,
183 Table_Low_Bound => 1,
185 Table_Increment => 200,
186 Table_Name => "Unchecked_Conversions");
188 ----------------------------------------
189 -- Table for Validate_Address_Clauses --
190 ----------------------------------------
192 -- If an address clause has the form
194 -- for X'Address use Expr
196 -- where Expr is of the form Y'Address or recursively is a reference
197 -- to a constant of either of these forms, and X and Y are entities of
198 -- objects, then if Y has a smaller alignment than X, that merits a
199 -- warning about possible bad alignment. The following table collects
200 -- address clauses of this kind. We put these in a table so that they
201 -- can be checked after the back end has completed annotation of the
202 -- alignments of objects, since we can catch more cases that way.
204 type Address_Clause_Check_Record is record
206 -- The address clause
209 -- The entity of the object overlaying Y
212 -- The entity of the object being overlaid
215 -- Whether the address is offset within Y
218 package Address_Clause_Checks is new Table.Table (
219 Table_Component_Type => Address_Clause_Check_Record,
220 Table_Index_Type => Int,
221 Table_Low_Bound => 1,
223 Table_Increment => 200,
224 Table_Name => "Address_Clause_Checks");
226 -----------------------------------------
227 -- Adjust_Record_For_Reverse_Bit_Order --
228 -----------------------------------------
230 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
235 -- Processing depends on version of Ada
237 -- For Ada 95, we just renumber bits within a storage unit. We do the
238 -- same for Ada 83 mode, since we recognize the Bit_Order attribute in
239 -- Ada 83, and are free to add this extension.
241 if Ada_Version < Ada_2005 then
242 Comp := First_Component_Or_Discriminant (R);
243 while Present (Comp) loop
244 CC := Component_Clause (Comp);
246 -- If component clause is present, then deal with the non-default
247 -- bit order case for Ada 95 mode.
249 -- We only do this processing for the base type, and in fact that
250 -- is important, since otherwise if there are record subtypes, we
251 -- could reverse the bits once for each subtype, which is wrong.
254 and then Ekind (R) = E_Record_Type
257 CFB : constant Uint := Component_Bit_Offset (Comp);
258 CSZ : constant Uint := Esize (Comp);
259 CLC : constant Node_Id := Component_Clause (Comp);
260 Pos : constant Node_Id := Position (CLC);
261 FB : constant Node_Id := First_Bit (CLC);
263 Storage_Unit_Offset : constant Uint :=
264 CFB / System_Storage_Unit;
266 Start_Bit : constant Uint :=
267 CFB mod System_Storage_Unit;
270 -- Cases where field goes over storage unit boundary
272 if Start_Bit + CSZ > System_Storage_Unit then
274 -- Allow multi-byte field but generate warning
276 if Start_Bit mod System_Storage_Unit = 0
277 and then CSZ mod System_Storage_Unit = 0
280 ("multi-byte field specified with non-standard"
281 & " Bit_Order?", CLC);
283 if Bytes_Big_Endian then
285 ("bytes are not reversed "
286 & "(component is big-endian)?", CLC);
289 ("bytes are not reversed "
290 & "(component is little-endian)?", CLC);
293 -- Do not allow non-contiguous field
297 ("attempt to specify non-contiguous field "
298 & "not permitted", CLC);
300 ("\caused by non-standard Bit_Order "
303 ("\consider possibility of using "
304 & "Ada 2005 mode here", CLC);
307 -- Case where field fits in one storage unit
310 -- Give warning if suspicious component clause
312 if Intval (FB) >= System_Storage_Unit
313 and then Warn_On_Reverse_Bit_Order
316 ("?Bit_Order clause does not affect " &
317 "byte ordering", Pos);
319 Intval (Pos) + Intval (FB) /
322 ("?position normalized to ^ before bit " &
323 "order interpreted", Pos);
326 -- Here is where we fix up the Component_Bit_Offset value
327 -- to account for the reverse bit order. Some examples of
328 -- what needs to be done are:
330 -- First_Bit .. Last_Bit Component_Bit_Offset
342 -- The rule is that the first bit is is obtained by
343 -- subtracting the old ending bit from storage_unit - 1.
345 Set_Component_Bit_Offset
347 (Storage_Unit_Offset * System_Storage_Unit) +
348 (System_Storage_Unit - 1) -
349 (Start_Bit + CSZ - 1));
351 Set_Normalized_First_Bit
353 Component_Bit_Offset (Comp) mod
354 System_Storage_Unit);
359 Next_Component_Or_Discriminant (Comp);
362 -- For Ada 2005, we do machine scalar processing, as fully described In
363 -- AI-133. This involves gathering all components which start at the
364 -- same byte offset and processing them together. Same approach is still
365 -- valid in later versions including Ada 2012.
369 Max_Machine_Scalar_Size : constant Uint :=
371 (Standard_Long_Long_Integer_Size);
372 -- We use this as the maximum machine scalar size
375 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
378 -- This first loop through components does two things. First it
379 -- deals with the case of components with component clauses whose
380 -- length is greater than the maximum machine scalar size (either
381 -- accepting them or rejecting as needed). Second, it counts the
382 -- number of components with component clauses whose length does
383 -- not exceed this maximum for later processing.
386 Comp := First_Component_Or_Discriminant (R);
387 while Present (Comp) loop
388 CC := Component_Clause (Comp);
392 Fbit : constant Uint :=
393 Static_Integer (First_Bit (CC));
394 Lbit : constant Uint :=
395 Static_Integer (Last_Bit (CC));
398 -- Case of component with last bit >= max machine scalar
400 if Lbit >= Max_Machine_Scalar_Size then
402 -- This is allowed only if first bit is zero, and
403 -- last bit + 1 is a multiple of storage unit size.
405 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
407 -- This is the case to give a warning if enabled
409 if Warn_On_Reverse_Bit_Order then
411 ("multi-byte field specified with "
412 & " non-standard Bit_Order?", CC);
414 if Bytes_Big_Endian then
416 ("\bytes are not reversed "
417 & "(component is big-endian)?", CC);
420 ("\bytes are not reversed "
421 & "(component is little-endian)?", CC);
425 -- Give error message for RM 13.4.1(10) violation
429 ("machine scalar rules not followed for&",
430 First_Bit (CC), Comp);
432 Error_Msg_Uint_1 := Lbit;
433 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
435 ("\last bit (^) exceeds maximum machine "
439 if (Lbit + 1) mod SSU /= 0 then
440 Error_Msg_Uint_1 := SSU;
442 ("\and is not a multiple of Storage_Unit (^) "
447 Error_Msg_Uint_1 := Fbit;
449 ("\and first bit (^) is non-zero "
455 -- OK case of machine scalar related component clause,
456 -- For now, just count them.
459 Num_CC := Num_CC + 1;
464 Next_Component_Or_Discriminant (Comp);
467 -- We need to sort the component clauses on the basis of the
468 -- Position values in the clause, so we can group clauses with
469 -- the same Position. together to determine the relevant machine
473 Comps : array (0 .. Num_CC) of Entity_Id;
474 -- Array to collect component and discriminant entities. The
475 -- data starts at index 1, the 0'th entry is for the sort
478 function CP_Lt (Op1, Op2 : Natural) return Boolean;
479 -- Compare routine for Sort
481 procedure CP_Move (From : Natural; To : Natural);
482 -- Move routine for Sort
484 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
488 -- Start and stop positions in the component list of the set of
489 -- components with the same starting position (that constitute
490 -- components in a single machine scalar).
493 -- Maximum last bit value of any component in this set
496 -- Corresponding machine scalar size
502 function CP_Lt (Op1, Op2 : Natural) return Boolean is
504 return Position (Component_Clause (Comps (Op1))) <
505 Position (Component_Clause (Comps (Op2)));
512 procedure CP_Move (From : Natural; To : Natural) is
514 Comps (To) := Comps (From);
517 -- Start of processing for Sort_CC
520 -- Collect the machine scalar relevant component clauses
523 Comp := First_Component_Or_Discriminant (R);
524 while Present (Comp) loop
526 CC : constant Node_Id := Component_Clause (Comp);
529 -- Collect only component clauses whose last bit is less
530 -- than machine scalar size. Any component clause whose
531 -- last bit exceeds this value does not take part in
532 -- machine scalar layout considerations. The test for
533 -- Error_Posted makes sure we exclude component clauses
534 -- for which we already posted an error.
537 and then not Error_Posted (Last_Bit (CC))
538 and then Static_Integer (Last_Bit (CC)) <
539 Max_Machine_Scalar_Size
541 Num_CC := Num_CC + 1;
542 Comps (Num_CC) := Comp;
546 Next_Component_Or_Discriminant (Comp);
549 -- Sort by ascending position number
551 Sorting.Sort (Num_CC);
553 -- We now have all the components whose size does not exceed
554 -- the max machine scalar value, sorted by starting position.
555 -- In this loop we gather groups of clauses starting at the
556 -- same position, to process them in accordance with AI-133.
559 while Stop < Num_CC loop
564 (Last_Bit (Component_Clause (Comps (Start))));
565 while Stop < Num_CC loop
567 (Position (Component_Clause (Comps (Stop + 1)))) =
569 (Position (Component_Clause (Comps (Stop))))
577 (Component_Clause (Comps (Stop)))));
583 -- Now we have a group of component clauses from Start to
584 -- Stop whose positions are identical, and MaxL is the
585 -- maximum last bit value of any of these components.
587 -- We need to determine the corresponding machine scalar
588 -- size. This loop assumes that machine scalar sizes are
589 -- even, and that each possible machine scalar has twice
590 -- as many bits as the next smaller one.
592 MSS := Max_Machine_Scalar_Size;
594 and then (MSS / 2) >= SSU
595 and then (MSS / 2) > MaxL
600 -- Here is where we fix up the Component_Bit_Offset value
601 -- to account for the reverse bit order. Some examples of
602 -- what needs to be done for the case of a machine scalar
605 -- First_Bit .. Last_Bit Component_Bit_Offset
617 -- The rule is that the first bit is obtained by subtracting
618 -- the old ending bit from machine scalar size - 1.
620 for C in Start .. Stop loop
622 Comp : constant Entity_Id := Comps (C);
623 CC : constant Node_Id :=
624 Component_Clause (Comp);
625 LB : constant Uint :=
626 Static_Integer (Last_Bit (CC));
627 NFB : constant Uint := MSS - Uint_1 - LB;
628 NLB : constant Uint := NFB + Esize (Comp) - 1;
629 Pos : constant Uint :=
630 Static_Integer (Position (CC));
633 if Warn_On_Reverse_Bit_Order then
634 Error_Msg_Uint_1 := MSS;
636 ("info: reverse bit order in machine " &
637 "scalar of length^?", First_Bit (CC));
638 Error_Msg_Uint_1 := NFB;
639 Error_Msg_Uint_2 := NLB;
641 if Bytes_Big_Endian then
643 ("?\info: big-endian range for "
644 & "component & is ^ .. ^",
645 First_Bit (CC), Comp);
648 ("?\info: little-endian range "
649 & "for component & is ^ .. ^",
650 First_Bit (CC), Comp);
654 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
655 Set_Normalized_First_Bit (Comp, NFB mod SSU);
662 end Adjust_Record_For_Reverse_Bit_Order;
664 -------------------------------------
665 -- Alignment_Check_For_Size_Change --
666 -------------------------------------
668 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint) is
670 -- If the alignment is known, and not set by a rep clause, and is
671 -- inconsistent with the size being set, then reset it to unknown,
672 -- we assume in this case that the size overrides the inherited
673 -- alignment, and that the alignment must be recomputed.
675 if Known_Alignment (Typ)
676 and then not Has_Alignment_Clause (Typ)
677 and then Size mod (Alignment (Typ) * SSU) /= 0
679 Init_Alignment (Typ);
681 end Alignment_Check_For_Size_Change;
683 -----------------------------------
684 -- Analyze_Aspect_Specifications --
685 -----------------------------------
687 procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is
692 L : constant List_Id := Aspect_Specifications (N);
694 Ins_Node : Node_Id := N;
695 -- Insert pragmas (except Pre/Post/Invariant/Predicate) after this node
697 -- The general processing involves building an attribute definition
698 -- clause or a pragma node that corresponds to the aspect. Then one
699 -- of two things happens:
701 -- If we are required to delay the evaluation of this aspect to the
702 -- freeze point, we attach the corresponding pragma/attribute definition
703 -- clause to the aspect specification node, which is then placed in the
704 -- Rep Item chain. In this case we mark the entity by setting the flag
705 -- Has_Delayed_Aspects and we evaluate the rep item at the freeze point.
707 -- If no delay is required, we just insert the pragma or attribute
708 -- after the declaration, and it will get processed by the normal
709 -- circuit. The From_Aspect_Specification flag is set on the pragma
710 -- or attribute definition node in either case to activate special
711 -- processing (e.g. not traversing the list of homonyms for inline).
713 Delay_Required : Boolean := False;
714 -- Set True if delay is required
717 pragma Assert (Present (L));
719 -- Loop through aspects
722 Aspect_Loop : while Present (Aspect) loop
724 Loc : constant Source_Ptr := Sloc (Aspect);
725 Id : constant Node_Id := Identifier (Aspect);
726 Expr : constant Node_Id := Expression (Aspect);
727 Nam : constant Name_Id := Chars (Id);
728 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
731 Eloc : Source_Ptr := Sloc (Expr);
732 -- Source location of expression, modified when we split PPC's
734 procedure Check_False_Aspect_For_Derived_Type;
735 -- This procedure checks for the case of a false aspect for a
736 -- derived type, which improperly tries to cancel an aspect
737 -- inherited from the parent;
739 -----------------------------------------
740 -- Check_False_Aspect_For_Derived_Type --
741 -----------------------------------------
743 procedure Check_False_Aspect_For_Derived_Type is
745 -- We are only checking derived types
747 if not Is_Derived_Type (E) then
752 when Aspect_Atomic | Aspect_Shared =>
753 if not Is_Atomic (E) then
757 when Aspect_Atomic_Components =>
758 if not Has_Atomic_Components (E) then
762 when Aspect_Discard_Names =>
763 if not Discard_Names (E) then
768 if not Is_Packed (E) then
772 when Aspect_Unchecked_Union =>
773 if not Is_Unchecked_Union (E) then
777 when Aspect_Volatile =>
778 if not Is_Volatile (E) then
782 when Aspect_Volatile_Components =>
783 if not Has_Volatile_Components (E) then
791 -- Fall through means we are canceling an inherited aspect
793 Error_Msg_Name_1 := Nam;
795 ("derived type& inherits aspect%, cannot cancel", Expr, E);
796 end Check_False_Aspect_For_Derived_Type;
798 -- Start of processing for Aspect_Loop
801 -- Skip aspect if already analyzed (not clear if this is needed)
803 if Analyzed (Aspect) then
807 -- Check restriction No_Implementation_Aspect_Specifications
809 if Impl_Defined_Aspects (A_Id) then
811 (No_Implementation_Aspect_Specifications, Aspect);
814 -- Check restriction No_Specification_Of_Aspect
816 Check_Restriction_No_Specification_Of_Aspect (Aspect);
818 -- Analyze this aspect
820 Set_Analyzed (Aspect);
821 Set_Entity (Aspect, E);
822 Ent := New_Occurrence_Of (E, Sloc (Id));
824 -- Check for duplicate aspect. Note that the Comes_From_Source
825 -- test allows duplicate Pre/Post's that we generate internally
826 -- to escape being flagged here.
828 if No_Duplicates_Allowed (A_Id) then
830 while Anod /= Aspect loop
832 (A_Id, Get_Aspect_Id (Chars (Identifier (Anod))))
833 and then Comes_From_Source (Aspect)
835 Error_Msg_Name_1 := Nam;
836 Error_Msg_Sloc := Sloc (Anod);
838 -- Case of same aspect specified twice
840 if Class_Present (Anod) = Class_Present (Aspect) then
841 if not Class_Present (Anod) then
843 ("aspect% for & previously given#",
847 ("aspect `%''Class` for & previously given#",
851 -- Case of Pre and Pre'Class both specified
853 elsif Nam = Name_Pre then
854 if Class_Present (Aspect) then
856 ("aspect `Pre''Class` for & is not allowed here",
859 ("\since aspect `Pre` previously given#",
864 ("aspect `Pre` for & is not allowed here",
867 ("\since aspect `Pre''Class` previously given#",
872 -- Allowed case of X and X'Class both specified
879 -- Copy expression for later processing by the procedures
880 -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations]
882 Set_Entity (Id, New_Copy_Tree (Expr));
884 -- Processing based on specific aspect
888 -- No_Aspect should be impossible
893 -- Aspects taking an optional boolean argument. For all of
894 -- these we just create a matching pragma and insert it, if
895 -- the expression is missing or set to True. If the expression
896 -- is False, we can ignore the aspect with the exception that
897 -- in the case of a derived type, we must check for an illegal
898 -- attempt to cancel an inherited aspect.
900 when Boolean_Aspects =>
901 Set_Is_Boolean_Aspect (Aspect);
904 and then Is_False (Static_Boolean (Expr))
906 Check_False_Aspect_For_Derived_Type;
910 -- If True, build corresponding pragma node
914 Pragma_Argument_Associations => New_List (Ent),
916 Make_Identifier (Sloc (Id), Chars (Id)));
918 -- Never need to delay for boolean aspects
920 pragma Assert (not Delay_Required);
922 -- Library unit aspects. These are boolean aspects, but we
923 -- have to do special things with the insertion, since the
924 -- pragma belongs inside the declarations of a package.
926 when Library_Unit_Aspects =>
928 and then Is_False (Static_Boolean (Expr))
933 -- Build corresponding pragma node
937 Pragma_Argument_Associations => New_List (Ent),
939 Make_Identifier (Sloc (Id), Chars (Id)));
941 -- This requires special handling in the case of a package
942 -- declaration, the pragma needs to be inserted in the list
943 -- of declarations for the associated package. There is no
944 -- issue of visibility delay for these aspects.
946 if Nkind (N) = N_Package_Declaration then
947 if Nkind (Parent (N)) /= N_Compilation_Unit then
949 ("incorrect context for library unit aspect&", Id);
952 (Aitem, Visible_Declarations (Specification (N)));
958 -- If not package declaration, no delay is required
960 pragma Assert (not Delay_Required);
962 -- Aspects related to container iterators. These aspects denote
963 -- subprograms, and thus must be delayed.
965 when Aspect_Constant_Indexing |
966 Aspect_Variable_Indexing =>
968 if not Is_Type (E) or else not Is_Tagged_Type (E) then
969 Error_Msg_N ("indexing applies to a tagged type", N);
973 Make_Attribute_Definition_Clause (Loc,
976 Expression => Relocate_Node (Expr));
978 Delay_Required := True;
979 Set_Is_Delayed_Aspect (Aspect);
981 when Aspect_Default_Iterator |
982 Aspect_Iterator_Element =>
985 Make_Attribute_Definition_Clause (Loc,
988 Expression => Relocate_Node (Expr));
990 Delay_Required := True;
991 Set_Is_Delayed_Aspect (Aspect);
993 when Aspect_Implicit_Dereference =>
995 or else not Has_Discriminants (E)
998 ("Aspect must apply to a type with discriminants", N);
1006 Disc := First_Discriminant (E);
1007 while Present (Disc) loop
1008 if Chars (Expr) = Chars (Disc)
1009 and then Ekind (Etype (Disc)) =
1010 E_Anonymous_Access_Type
1012 Set_Has_Implicit_Dereference (E);
1013 Set_Has_Implicit_Dereference (Disc);
1017 Next_Discriminant (Disc);
1020 -- Error if no proper access discriminant.
1023 ("not an access discriminant of&", Expr, E);
1029 -- Aspects corresponding to attribute definition clauses
1031 when Aspect_Address |
1034 Aspect_Component_Size |
1035 Aspect_External_Tag |
1037 Aspect_Machine_Radix |
1038 Aspect_Object_Size |
1043 Aspect_Storage_Pool |
1044 Aspect_Storage_Size |
1045 Aspect_Stream_Size |
1049 -- Construct the attribute definition clause
1052 Make_Attribute_Definition_Clause (Loc,
1054 Chars => Chars (Id),
1055 Expression => Relocate_Node (Expr));
1057 -- A delay is required except in the common case where
1058 -- the expression is a literal, in which case it is fine
1059 -- to take care of it right away.
1061 if Nkind_In (Expr, N_Integer_Literal, N_String_Literal) then
1062 pragma Assert (not Delay_Required);
1065 Delay_Required := True;
1066 Set_Is_Delayed_Aspect (Aspect);
1069 -- Aspects corresponding to pragmas with two arguments, where
1070 -- the first argument is a local name referring to the entity,
1071 -- and the second argument is the aspect definition expression
1072 -- which is an expression that does not get analyzed.
1074 when Aspect_Suppress |
1075 Aspect_Unsuppress =>
1077 -- Construct the pragma
1081 Pragma_Argument_Associations => New_List (
1082 New_Occurrence_Of (E, Loc),
1083 Relocate_Node (Expr)),
1084 Pragma_Identifier =>
1085 Make_Identifier (Sloc (Id), Chars (Id)));
1087 -- We don't have to play the delay game here, since the only
1088 -- values are check names which don't get analyzed anyway.
1090 pragma Assert (not Delay_Required);
1092 -- Aspects corresponding to pragmas with two arguments, where
1093 -- the second argument is a local name referring to the entity,
1094 -- and the first argument is the aspect definition expression.
1096 when Aspect_Warnings =>
1098 -- Construct the pragma
1102 Pragma_Argument_Associations => New_List (
1103 Relocate_Node (Expr),
1104 New_Occurrence_Of (E, Loc)),
1105 Pragma_Identifier =>
1106 Make_Identifier (Sloc (Id), Chars (Id)),
1107 Class_Present => Class_Present (Aspect));
1109 -- We don't have to play the delay game here, since the only
1110 -- values are ON/OFF which don't get analyzed anyway.
1112 pragma Assert (not Delay_Required);
1114 -- Default_Value and Default_Component_Value aspects. These
1115 -- are specially handled because they have no corresponding
1116 -- pragmas or attributes.
1118 when Aspect_Default_Value | Aspect_Default_Component_Value =>
1119 Error_Msg_Name_1 := Chars (Id);
1121 if not Is_Type (E) then
1122 Error_Msg_N ("aspect% can only apply to a type", Id);
1125 elsif not Is_First_Subtype (E) then
1126 Error_Msg_N ("aspect% cannot apply to subtype", Id);
1129 elsif A_Id = Aspect_Default_Value
1130 and then not Is_Scalar_Type (E)
1133 ("aspect% can only be applied to scalar type", Id);
1136 elsif A_Id = Aspect_Default_Component_Value then
1137 if not Is_Array_Type (E) then
1139 ("aspect% can only be applied to array type", Id);
1141 elsif not Is_Scalar_Type (Component_Type (E)) then
1143 ("aspect% requires scalar components", Id);
1149 Delay_Required := True;
1150 Set_Is_Delayed_Aspect (Aspect);
1151 Set_Has_Default_Aspect (Base_Type (Entity (Ent)));
1153 when Aspect_Attach_Handler =>
1156 Pragma_Identifier =>
1157 Make_Identifier (Sloc (Id), Name_Attach_Handler),
1158 Pragma_Argument_Associations =>
1159 New_List (Ent, Relocate_Node (Expr)));
1161 Set_From_Aspect_Specification (Aitem, True);
1162 Set_Corresponding_Aspect (Aitem, Aspect);
1164 pragma Assert (not Delay_Required);
1166 when Aspect_Priority |
1167 Aspect_Interrupt_Priority |
1168 Aspect_Dispatching_Domain |
1174 if A_Id = Aspect_Priority then
1175 Pname := Name_Priority;
1177 elsif A_Id = Aspect_Interrupt_Priority then
1178 Pname := Name_Interrupt_Priority;
1180 elsif A_Id = Aspect_CPU then
1184 Pname := Name_Dispatching_Domain;
1189 Pragma_Identifier =>
1190 Make_Identifier (Sloc (Id), Pname),
1191 Pragma_Argument_Associations =>
1193 (Make_Pragma_Argument_Association
1195 Expression => Relocate_Node (Expr))));
1197 Set_From_Aspect_Specification (Aitem, True);
1198 Set_Corresponding_Aspect (Aitem, Aspect);
1200 pragma Assert (not Delay_Required);
1203 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
1204 -- with a first argument that is the expression, and a second
1205 -- argument that is an informative message if the test fails.
1206 -- This is inserted right after the declaration, to get the
1207 -- required pragma placement. The processing for the pragmas
1208 -- takes care of the required delay.
1210 when Pre_Post_Aspects => declare
1214 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
1215 Pname := Name_Precondition;
1217 Pname := Name_Postcondition;
1220 -- If the expressions is of the form A and then B, then
1221 -- we generate separate Pre/Post aspects for the separate
1222 -- clauses. Since we allow multiple pragmas, there is no
1223 -- problem in allowing multiple Pre/Post aspects internally.
1224 -- These should be treated in reverse order (B first and
1225 -- A second) since they are later inserted just after N in
1226 -- the order they are treated. This way, the pragma for A
1227 -- ends up preceding the pragma for B, which may have an
1228 -- importance for the error raised (either constraint error
1229 -- or precondition error).
1231 -- We do not do this for Pre'Class, since we have to put
1232 -- these conditions together in a complex OR expression
1234 -- We do not do this in ASIS mode, as ASIS relies on the
1235 -- original node representing the complete expression, when
1236 -- retrieving it through the source aspect table.
1239 and then (Pname = Name_Postcondition
1240 or else not Class_Present (Aspect))
1242 while Nkind (Expr) = N_And_Then loop
1243 Insert_After (Aspect,
1244 Make_Aspect_Specification (Sloc (Left_Opnd (Expr)),
1245 Identifier => Identifier (Aspect),
1246 Expression => Relocate_Node (Left_Opnd (Expr)),
1247 Class_Present => Class_Present (Aspect),
1248 Split_PPC => True));
1249 Rewrite (Expr, Relocate_Node (Right_Opnd (Expr)));
1250 Eloc := Sloc (Expr);
1254 -- Build the precondition/postcondition pragma
1258 Pragma_Identifier =>
1259 Make_Identifier (Sloc (Id), Pname),
1260 Class_Present => Class_Present (Aspect),
1261 Split_PPC => Split_PPC (Aspect),
1262 Pragma_Argument_Associations => New_List (
1263 Make_Pragma_Argument_Association (Eloc,
1264 Chars => Name_Check,
1265 Expression => Relocate_Node (Expr))));
1267 -- Add message unless exception messages are suppressed
1269 if not Opt.Exception_Locations_Suppressed then
1270 Append_To (Pragma_Argument_Associations (Aitem),
1271 Make_Pragma_Argument_Association (Eloc,
1272 Chars => Name_Message,
1274 Make_String_Literal (Eloc,
1276 & Get_Name_String (Pname)
1278 & Build_Location_String (Eloc))));
1281 Set_From_Aspect_Specification (Aitem, True);
1282 Set_Corresponding_Aspect (Aitem, Aspect);
1283 Set_Is_Delayed_Aspect (Aspect);
1285 -- For Pre/Post cases, insert immediately after the entity
1286 -- declaration, since that is the required pragma placement.
1287 -- Note that for these aspects, we do not have to worry
1288 -- about delay issues, since the pragmas themselves deal
1289 -- with delay of visibility for the expression analysis.
1291 -- If the entity is a library-level subprogram, the pre/
1292 -- postconditions must be treated as late pragmas.
1294 if Nkind (Parent (N)) = N_Compilation_Unit then
1295 Add_Global_Declaration (Aitem);
1297 Insert_After (N, Aitem);
1303 -- Invariant aspects generate a corresponding pragma with a
1304 -- first argument that is the entity, a second argument that is
1305 -- the expression and a third argument that is an appropriate
1306 -- message. This is inserted right after the declaration, to
1307 -- get the required pragma placement. The pragma processing
1308 -- takes care of the required delay.
1310 when Aspect_Invariant |
1311 Aspect_Type_Invariant =>
1313 -- Analysis of the pragma will verify placement legality:
1314 -- an invariant must apply to a private type, or appear in
1315 -- the private part of a spec and apply to a completion.
1317 -- Construct the pragma
1321 Pragma_Argument_Associations =>
1322 New_List (Ent, Relocate_Node (Expr)),
1323 Class_Present => Class_Present (Aspect),
1324 Pragma_Identifier =>
1325 Make_Identifier (Sloc (Id), Name_Invariant));
1327 -- Add message unless exception messages are suppressed
1329 if not Opt.Exception_Locations_Suppressed then
1330 Append_To (Pragma_Argument_Associations (Aitem),
1331 Make_Pragma_Argument_Association (Eloc,
1332 Chars => Name_Message,
1334 Make_String_Literal (Eloc,
1335 Strval => "failed invariant from "
1336 & Build_Location_String (Eloc))));
1339 Set_From_Aspect_Specification (Aitem, True);
1340 Set_Corresponding_Aspect (Aitem, Aspect);
1341 Set_Is_Delayed_Aspect (Aspect);
1343 -- For Invariant case, insert immediately after the entity
1344 -- declaration. We do not have to worry about delay issues
1345 -- since the pragma processing takes care of this.
1347 Insert_After (N, Aitem);
1350 -- Predicate aspects generate a corresponding pragma with a
1351 -- first argument that is the entity, and the second argument
1352 -- is the expression.
1354 when Aspect_Dynamic_Predicate |
1356 Aspect_Static_Predicate =>
1358 -- Construct the pragma (always a pragma Predicate, with
1359 -- flags recording whether it is static/dynamic).
1363 Pragma_Argument_Associations =>
1364 New_List (Ent, Relocate_Node (Expr)),
1365 Class_Present => Class_Present (Aspect),
1366 Pragma_Identifier =>
1367 Make_Identifier (Sloc (Id), Name_Predicate));
1369 Set_From_Aspect_Specification (Aitem, True);
1370 Set_Corresponding_Aspect (Aitem, Aspect);
1372 -- Make sure we have a freeze node (it might otherwise be
1373 -- missing in cases like subtype X is Y, and we would not
1374 -- have a place to build the predicate function).
1376 Set_Has_Predicates (E);
1378 if Is_Private_Type (E)
1379 and then Present (Full_View (E))
1381 Set_Has_Predicates (Full_View (E));
1382 Set_Has_Delayed_Aspects (Full_View (E));
1385 Ensure_Freeze_Node (E);
1386 Set_Is_Delayed_Aspect (Aspect);
1387 Delay_Required := True;
1389 when Aspect_Test_Case => declare
1391 Comp_Expr : Node_Id;
1392 Comp_Assn : Node_Id;
1398 if Nkind (Parent (N)) = N_Compilation_Unit then
1400 ("incorrect placement of aspect `Test_Case`", E);
1404 if Nkind (Expr) /= N_Aggregate then
1406 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1410 -- Make pragma expressions refer to the original aspect
1411 -- expressions through the Original_Node link. This is used
1412 -- in semantic analysis for ASIS mode, so that the original
1413 -- expression also gets analyzed.
1415 Comp_Expr := First (Expressions (Expr));
1416 while Present (Comp_Expr) loop
1417 New_Expr := Relocate_Node (Comp_Expr);
1418 Set_Original_Node (New_Expr, Comp_Expr);
1420 (Make_Pragma_Argument_Association (Sloc (Comp_Expr),
1421 Expression => New_Expr),
1426 Comp_Assn := First (Component_Associations (Expr));
1427 while Present (Comp_Assn) loop
1428 if List_Length (Choices (Comp_Assn)) /= 1
1430 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
1433 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1437 New_Expr := Relocate_Node (Expression (Comp_Assn));
1438 Set_Original_Node (New_Expr, Expression (Comp_Assn));
1439 Append (Make_Pragma_Argument_Association (
1440 Sloc => Sloc (Comp_Assn),
1441 Chars => Chars (First (Choices (Comp_Assn))),
1442 Expression => New_Expr),
1447 -- Build the test-case pragma
1451 Pragma_Identifier =>
1452 Make_Identifier (Sloc (Id), Name_Test_Case),
1453 Pragma_Argument_Associations =>
1456 Set_From_Aspect_Specification (Aitem, True);
1457 Set_Corresponding_Aspect (Aitem, Aspect);
1458 Set_Is_Delayed_Aspect (Aspect);
1460 -- Insert immediately after the entity declaration
1462 Insert_After (N, Aitem);
1468 -- If a delay is required, we delay the freeze (not much point in
1469 -- delaying the aspect if we don't delay the freeze!). The pragma
1470 -- or attribute clause if there is one is then attached to the
1471 -- aspect specification which is placed in the rep item list.
1473 if Delay_Required then
1474 if Present (Aitem) then
1475 Set_From_Aspect_Specification (Aitem, True);
1477 if Nkind (Aitem) = N_Pragma then
1478 Set_Corresponding_Aspect (Aitem, Aspect);
1481 Set_Is_Delayed_Aspect (Aitem);
1482 Set_Aspect_Rep_Item (Aspect, Aitem);
1485 Ensure_Freeze_Node (E);
1486 Set_Has_Delayed_Aspects (E);
1487 Record_Rep_Item (E, Aspect);
1489 -- If no delay required, insert the pragma/clause in the tree
1492 Set_From_Aspect_Specification (Aitem, True);
1494 if Nkind (Aitem) = N_Pragma then
1495 Set_Corresponding_Aspect (Aitem, Aspect);
1498 -- If this is a compilation unit, we will put the pragma in
1499 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1501 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1503 Aux : constant Node_Id :=
1504 Aux_Decls_Node (Parent (Ins_Node));
1507 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1509 if No (Pragmas_After (Aux)) then
1510 Set_Pragmas_After (Aux, Empty_List);
1513 -- For Pre_Post put at start of list, otherwise at end
1515 if A_Id in Pre_Post_Aspects then
1516 Prepend (Aitem, Pragmas_After (Aux));
1518 Append (Aitem, Pragmas_After (Aux));
1522 -- Here if not compilation unit case
1527 -- For Pre/Post cases, insert immediately after the
1528 -- entity declaration, since that is the required pragma
1531 when Pre_Post_Aspects =>
1532 Insert_After (N, Aitem);
1534 -- For Priority aspects, insert into the task or
1535 -- protected definition, which we need to create if it's
1536 -- not there. The same applies to CPU and
1537 -- Dispatching_Domain but only to tasks.
1539 when Aspect_Priority |
1540 Aspect_Interrupt_Priority |
1541 Aspect_Dispatching_Domain |
1544 T : Node_Id; -- the type declaration
1545 L : List_Id; -- list of decls of task/protected
1548 if Nkind (N) = N_Object_Declaration then
1549 T := Parent (Etype (Defining_Identifier (N)));
1554 if Nkind (T) = N_Protected_Type_Declaration
1555 and then A_Id /= Aspect_Dispatching_Domain
1556 and then A_Id /= Aspect_CPU
1559 (Present (Protected_Definition (T)));
1561 L := Visible_Declarations
1562 (Protected_Definition (T));
1564 elsif Nkind (T) = N_Task_Type_Declaration then
1565 if No (Task_Definition (T)) then
1568 Make_Task_Definition
1570 Visible_Declarations => New_List,
1571 End_Label => Empty));
1574 L := Visible_Declarations (Task_Definition (T));
1577 raise Program_Error;
1580 Prepend (Aitem, To => L);
1582 -- Analyze rewritten pragma. Otherwise, its
1583 -- analysis is done too late, after the task or
1584 -- protected object has been created.
1589 -- For all other cases, insert in sequence
1592 Insert_After (Ins_Node, Aitem);
1601 end loop Aspect_Loop;
1602 end Analyze_Aspect_Specifications;
1604 -----------------------
1605 -- Analyze_At_Clause --
1606 -----------------------
1608 -- An at clause is replaced by the corresponding Address attribute
1609 -- definition clause that is the preferred approach in Ada 95.
1611 procedure Analyze_At_Clause (N : Node_Id) is
1612 CS : constant Boolean := Comes_From_Source (N);
1615 -- This is an obsolescent feature
1617 Check_Restriction (No_Obsolescent_Features, N);
1619 if Warn_On_Obsolescent_Feature then
1621 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1623 ("\use address attribute definition clause instead?", N);
1626 -- Rewrite as address clause
1629 Make_Attribute_Definition_Clause (Sloc (N),
1630 Name => Identifier (N),
1631 Chars => Name_Address,
1632 Expression => Expression (N)));
1634 -- We preserve Comes_From_Source, since logically the clause still
1635 -- comes from the source program even though it is changed in form.
1637 Set_Comes_From_Source (N, CS);
1639 -- Analyze rewritten clause
1641 Analyze_Attribute_Definition_Clause (N);
1642 end Analyze_At_Clause;
1644 -----------------------------------------
1645 -- Analyze_Attribute_Definition_Clause --
1646 -----------------------------------------
1648 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1649 Loc : constant Source_Ptr := Sloc (N);
1650 Nam : constant Node_Id := Name (N);
1651 Attr : constant Name_Id := Chars (N);
1652 Expr : constant Node_Id := Expression (N);
1653 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1656 -- The entity of Nam after it is analyzed. In the case of an incomplete
1657 -- type, this is the underlying type.
1660 -- The underlying entity to which the attribute applies. Generally this
1661 -- is the Underlying_Type of Ent, except in the case where the clause
1662 -- applies to full view of incomplete type or private type in which case
1663 -- U_Ent is just a copy of Ent.
1665 FOnly : Boolean := False;
1666 -- Reset to True for subtype specific attribute (Alignment, Size)
1667 -- and for stream attributes, i.e. those cases where in the call
1668 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1669 -- rules are checked. Note that the case of stream attributes is not
1670 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1671 -- disallow Storage_Size for derived task types, but that is also
1672 -- clearly unintentional.
1674 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1675 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1676 -- definition clauses.
1678 function Duplicate_Clause return Boolean;
1679 -- This routine checks if the aspect for U_Ent being given by attribute
1680 -- definition clause N is for an aspect that has already been specified,
1681 -- and if so gives an error message. If there is a duplicate, True is
1682 -- returned, otherwise if there is no error, False is returned.
1684 procedure Check_Indexing_Functions;
1685 -- Check that the function in Constant_Indexing or Variable_Indexing
1686 -- attribute has the proper type structure. If the name is overloaded,
1687 -- check that all interpretations are legal.
1689 procedure Check_Iterator_Functions;
1690 -- Check that there is a single function in Default_Iterator attribute
1691 -- has the proper type structure.
1693 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
1694 -- Common legality check for the previous two
1696 -----------------------------------
1697 -- Analyze_Stream_TSS_Definition --
1698 -----------------------------------
1700 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1701 Subp : Entity_Id := Empty;
1706 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1707 -- True for Read attribute, false for other attributes
1709 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1710 -- Return true if the entity is a subprogram with an appropriate
1711 -- profile for the attribute being defined.
1713 ----------------------
1714 -- Has_Good_Profile --
1715 ----------------------
1717 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1719 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1720 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1721 (False => E_Procedure, True => E_Function);
1725 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1729 F := First_Formal (Subp);
1732 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1733 or else Designated_Type (Etype (F)) /=
1734 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1739 if not Is_Function then
1743 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1744 (False => E_In_Parameter,
1745 True => E_Out_Parameter);
1747 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1755 Typ := Etype (Subp);
1758 return Base_Type (Typ) = Base_Type (Ent)
1759 and then No (Next_Formal (F));
1760 end Has_Good_Profile;
1762 -- Start of processing for Analyze_Stream_TSS_Definition
1767 if not Is_Type (U_Ent) then
1768 Error_Msg_N ("local name must be a subtype", Nam);
1772 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1774 -- If Pnam is present, it can be either inherited from an ancestor
1775 -- type (in which case it is legal to redefine it for this type), or
1776 -- be a previous definition of the attribute for the same type (in
1777 -- which case it is illegal).
1779 -- In the first case, it will have been analyzed already, and we
1780 -- can check that its profile does not match the expected profile
1781 -- for a stream attribute of U_Ent. In the second case, either Pnam
1782 -- has been analyzed (and has the expected profile), or it has not
1783 -- been analyzed yet (case of a type that has not been frozen yet
1784 -- and for which the stream attribute has been set using Set_TSS).
1787 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1789 Error_Msg_Sloc := Sloc (Pnam);
1790 Error_Msg_Name_1 := Attr;
1791 Error_Msg_N ("% attribute already defined #", Nam);
1797 if Is_Entity_Name (Expr) then
1798 if not Is_Overloaded (Expr) then
1799 if Has_Good_Profile (Entity (Expr)) then
1800 Subp := Entity (Expr);
1804 Get_First_Interp (Expr, I, It);
1805 while Present (It.Nam) loop
1806 if Has_Good_Profile (It.Nam) then
1811 Get_Next_Interp (I, It);
1816 if Present (Subp) then
1817 if Is_Abstract_Subprogram (Subp) then
1818 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1822 Set_Entity (Expr, Subp);
1823 Set_Etype (Expr, Etype (Subp));
1825 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1828 Error_Msg_Name_1 := Attr;
1829 Error_Msg_N ("incorrect expression for% attribute", Expr);
1831 end Analyze_Stream_TSS_Definition;
1833 ------------------------------
1834 -- Check_Indexing_Functions --
1835 ------------------------------
1837 procedure Check_Indexing_Functions is
1839 procedure Check_One_Function (Subp : Entity_Id);
1840 -- Check one possible interpretation
1842 ------------------------
1843 -- Check_One_Function --
1844 ------------------------
1846 procedure Check_One_Function (Subp : Entity_Id) is
1848 if not Check_Primitive_Function (Subp) then
1850 ("aspect Indexing requires a function that applies to type&",
1854 if not Has_Implicit_Dereference (Etype (Subp)) then
1856 ("function for indexing must return a reference type", Subp);
1858 end Check_One_Function;
1860 -- Start of processing for Check_Indexing_Functions
1869 if not Is_Overloaded (Expr) then
1870 Check_One_Function (Entity (Expr));
1878 Get_First_Interp (Expr, I, It);
1879 while Present (It.Nam) loop
1881 -- Note that analysis will have added the interpretation
1882 -- that corresponds to the dereference. We only check the
1883 -- subprogram itself.
1885 if Is_Overloadable (It.Nam) then
1886 Check_One_Function (It.Nam);
1889 Get_Next_Interp (I, It);
1893 end Check_Indexing_Functions;
1895 ------------------------------
1896 -- Check_Iterator_Functions --
1897 ------------------------------
1899 procedure Check_Iterator_Functions is
1900 Default : Entity_Id;
1902 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
1903 -- Check one possible interpretation for validity
1905 ----------------------------
1906 -- Valid_Default_Iterator --
1907 ----------------------------
1909 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
1913 if not Check_Primitive_Function (Subp) then
1916 Formal := First_Formal (Subp);
1919 -- False if any subsequent formal has no default expression
1921 Formal := Next_Formal (Formal);
1922 while Present (Formal) loop
1923 if No (Expression (Parent (Formal))) then
1927 Next_Formal (Formal);
1930 -- True if all subsequent formals have default expressions
1933 end Valid_Default_Iterator;
1935 -- Start of processing for Check_Iterator_Functions
1940 if not Is_Entity_Name (Expr) then
1941 Error_Msg_N ("aspect Iterator must be a function name", Expr);
1944 if not Is_Overloaded (Expr) then
1945 if not Check_Primitive_Function (Entity (Expr)) then
1947 ("aspect Indexing requires a function that applies to type&",
1948 Entity (Expr), Ent);
1951 if not Valid_Default_Iterator (Entity (Expr)) then
1952 Error_Msg_N ("improper function for default iterator", Expr);
1962 Get_First_Interp (Expr, I, It);
1963 while Present (It.Nam) loop
1964 if not Check_Primitive_Function (It.Nam)
1965 or else not Valid_Default_Iterator (It.Nam)
1969 elsif Present (Default) then
1970 Error_Msg_N ("default iterator must be unique", Expr);
1976 Get_Next_Interp (I, It);
1980 if Present (Default) then
1981 Set_Entity (Expr, Default);
1982 Set_Is_Overloaded (Expr, False);
1985 end Check_Iterator_Functions;
1987 -------------------------------
1988 -- Check_Primitive_Function --
1989 -------------------------------
1991 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
1995 if Ekind (Subp) /= E_Function then
1999 if No (First_Formal (Subp)) then
2002 Ctrl := Etype (First_Formal (Subp));
2006 or else Ctrl = Class_Wide_Type (Ent)
2008 (Ekind (Ctrl) = E_Anonymous_Access_Type
2010 (Designated_Type (Ctrl) = Ent
2011 or else Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
2020 end Check_Primitive_Function;
2022 ----------------------
2023 -- Duplicate_Clause --
2024 ----------------------
2026 function Duplicate_Clause return Boolean is
2030 -- Nothing to do if this attribute definition clause comes from
2031 -- an aspect specification, since we could not be duplicating an
2032 -- explicit clause, and we dealt with the case of duplicated aspects
2033 -- in Analyze_Aspect_Specifications.
2035 if From_Aspect_Specification (N) then
2039 -- Otherwise current clause may duplicate previous clause or a
2040 -- previously given aspect specification for the same aspect.
2042 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
2045 if Entity (A) = U_Ent then
2046 Error_Msg_Name_1 := Chars (N);
2047 Error_Msg_Sloc := Sloc (A);
2048 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
2054 end Duplicate_Clause;
2056 -- Start of processing for Analyze_Attribute_Definition_Clause
2059 -- The following code is a defense against recursion. Not clear that
2060 -- this can happen legitimately, but perhaps some error situations
2061 -- can cause it, and we did see this recursion during testing.
2063 if Analyzed (N) then
2066 Set_Analyzed (N, True);
2069 -- Process Ignore_Rep_Clauses option (we also ignore rep clauses in
2070 -- CodePeer mode or Alfa mode, since they are not relevant in these
2073 if Ignore_Rep_Clauses or CodePeer_Mode or Alfa_Mode then
2076 -- The following should be ignored. They do not affect legality
2077 -- and may be target dependent. The basic idea of -gnatI is to
2078 -- ignore any rep clauses that may be target dependent but do not
2079 -- affect legality (except possibly to be rejected because they
2080 -- are incompatible with the compilation target).
2082 when Attribute_Alignment |
2083 Attribute_Bit_Order |
2084 Attribute_Component_Size |
2085 Attribute_Machine_Radix |
2086 Attribute_Object_Size |
2088 Attribute_Stream_Size |
2089 Attribute_Value_Size =>
2090 Rewrite (N, Make_Null_Statement (Sloc (N)));
2093 -- We do not want too ignore 'Small in CodePeer_Mode or Alfa_Mode,
2094 -- since it has an impact on the exact computations performed.
2096 -- Perhaps 'Small should also not be ignored by
2097 -- Ignore_Rep_Clauses ???
2099 when Attribute_Small =>
2100 if Ignore_Rep_Clauses then
2101 Rewrite (N, Make_Null_Statement (Sloc (N)));
2105 -- The following should not be ignored, because in the first place
2106 -- they are reasonably portable, and should not cause problems in
2107 -- compiling code from another target, and also they do affect
2108 -- legality, e.g. failing to provide a stream attribute for a
2109 -- type may make a program illegal.
2111 when Attribute_External_Tag |
2115 Attribute_Storage_Pool |
2116 Attribute_Storage_Size |
2120 -- Other cases are errors ("attribute& cannot be set with
2121 -- definition clause"), which will be caught below.
2129 Ent := Entity (Nam);
2131 if Rep_Item_Too_Early (Ent, N) then
2135 -- Rep clause applies to full view of incomplete type or private type if
2136 -- we have one (if not, this is a premature use of the type). However,
2137 -- certain semantic checks need to be done on the specified entity (i.e.
2138 -- the private view), so we save it in Ent.
2140 if Is_Private_Type (Ent)
2141 and then Is_Derived_Type (Ent)
2142 and then not Is_Tagged_Type (Ent)
2143 and then No (Full_View (Ent))
2145 -- If this is a private type whose completion is a derivation from
2146 -- another private type, there is no full view, and the attribute
2147 -- belongs to the type itself, not its underlying parent.
2151 elsif Ekind (Ent) = E_Incomplete_Type then
2153 -- The attribute applies to the full view, set the entity of the
2154 -- attribute definition accordingly.
2156 Ent := Underlying_Type (Ent);
2158 Set_Entity (Nam, Ent);
2161 U_Ent := Underlying_Type (Ent);
2164 -- Complete other routine error checks
2166 if Etype (Nam) = Any_Type then
2169 elsif Scope (Ent) /= Current_Scope then
2170 Error_Msg_N ("entity must be declared in this scope", Nam);
2173 elsif No (U_Ent) then
2176 elsif Is_Type (U_Ent)
2177 and then not Is_First_Subtype (U_Ent)
2178 and then Id /= Attribute_Object_Size
2179 and then Id /= Attribute_Value_Size
2180 and then not From_At_Mod (N)
2182 Error_Msg_N ("cannot specify attribute for subtype", Nam);
2186 Set_Entity (N, U_Ent);
2188 -- Switch on particular attribute
2196 -- Address attribute definition clause
2198 when Attribute_Address => Address : begin
2200 -- A little error check, catch for X'Address use X'Address;
2202 if Nkind (Nam) = N_Identifier
2203 and then Nkind (Expr) = N_Attribute_Reference
2204 and then Attribute_Name (Expr) = Name_Address
2205 and then Nkind (Prefix (Expr)) = N_Identifier
2206 and then Chars (Nam) = Chars (Prefix (Expr))
2209 ("address for & is self-referencing", Prefix (Expr), Ent);
2213 -- Not that special case, carry on with analysis of expression
2215 Analyze_And_Resolve (Expr, RTE (RE_Address));
2217 -- Even when ignoring rep clauses we need to indicate that the
2218 -- entity has an address clause and thus it is legal to declare
2221 if Ignore_Rep_Clauses then
2222 if Ekind_In (U_Ent, E_Variable, E_Constant) then
2223 Record_Rep_Item (U_Ent, N);
2229 if Duplicate_Clause then
2232 -- Case of address clause for subprogram
2234 elsif Is_Subprogram (U_Ent) then
2235 if Has_Homonym (U_Ent) then
2237 ("address clause cannot be given " &
2238 "for overloaded subprogram",
2243 -- For subprograms, all address clauses are permitted, and we
2244 -- mark the subprogram as having a deferred freeze so that Gigi
2245 -- will not elaborate it too soon.
2247 -- Above needs more comments, what is too soon about???
2249 Set_Has_Delayed_Freeze (U_Ent);
2251 -- Case of address clause for entry
2253 elsif Ekind (U_Ent) = E_Entry then
2254 if Nkind (Parent (N)) = N_Task_Body then
2256 ("entry address must be specified in task spec", Nam);
2260 -- For entries, we require a constant address
2262 Check_Constant_Address_Clause (Expr, U_Ent);
2264 -- Special checks for task types
2266 if Is_Task_Type (Scope (U_Ent))
2267 and then Comes_From_Source (Scope (U_Ent))
2270 ("?entry address declared for entry in task type", N);
2272 ("\?only one task can be declared of this type", N);
2275 -- Entry address clauses are obsolescent
2277 Check_Restriction (No_Obsolescent_Features, N);
2279 if Warn_On_Obsolescent_Feature then
2281 ("attaching interrupt to task entry is an " &
2282 "obsolescent feature (RM J.7.1)?", N);
2284 ("\use interrupt procedure instead?", N);
2287 -- Case of an address clause for a controlled object which we
2288 -- consider to be erroneous.
2290 elsif Is_Controlled (Etype (U_Ent))
2291 or else Has_Controlled_Component (Etype (U_Ent))
2294 ("?controlled object& must not be overlaid", Nam, U_Ent);
2296 ("\?Program_Error will be raised at run time", Nam);
2297 Insert_Action (Declaration_Node (U_Ent),
2298 Make_Raise_Program_Error (Loc,
2299 Reason => PE_Overlaid_Controlled_Object));
2302 -- Case of address clause for a (non-controlled) object
2305 Ekind (U_Ent) = E_Variable
2307 Ekind (U_Ent) = E_Constant
2310 Expr : constant Node_Id := Expression (N);
2315 -- Exported variables cannot have an address clause, because
2316 -- this cancels the effect of the pragma Export.
2318 if Is_Exported (U_Ent) then
2320 ("cannot export object with address clause", Nam);
2324 Find_Overlaid_Entity (N, O_Ent, Off);
2326 -- Overlaying controlled objects is erroneous
2329 and then (Has_Controlled_Component (Etype (O_Ent))
2330 or else Is_Controlled (Etype (O_Ent)))
2333 ("?cannot overlay with controlled object", Expr);
2335 ("\?Program_Error will be raised at run time", Expr);
2336 Insert_Action (Declaration_Node (U_Ent),
2337 Make_Raise_Program_Error (Loc,
2338 Reason => PE_Overlaid_Controlled_Object));
2341 elsif Present (O_Ent)
2342 and then Ekind (U_Ent) = E_Constant
2343 and then not Is_Constant_Object (O_Ent)
2345 Error_Msg_N ("constant overlays a variable?", Expr);
2347 elsif Present (Renamed_Object (U_Ent)) then
2349 ("address clause not allowed"
2350 & " for a renaming declaration (RM 13.1(6))", Nam);
2353 -- Imported variables can have an address clause, but then
2354 -- the import is pretty meaningless except to suppress
2355 -- initializations, so we do not need such variables to
2356 -- be statically allocated (and in fact it causes trouble
2357 -- if the address clause is a local value).
2359 elsif Is_Imported (U_Ent) then
2360 Set_Is_Statically_Allocated (U_Ent, False);
2363 -- We mark a possible modification of a variable with an
2364 -- address clause, since it is likely aliasing is occurring.
2366 Note_Possible_Modification (Nam, Sure => False);
2368 -- Here we are checking for explicit overlap of one variable
2369 -- by another, and if we find this then mark the overlapped
2370 -- variable as also being volatile to prevent unwanted
2371 -- optimizations. This is a significant pessimization so
2372 -- avoid it when there is an offset, i.e. when the object
2373 -- is composite; they cannot be optimized easily anyway.
2376 and then Is_Object (O_Ent)
2379 Set_Treat_As_Volatile (O_Ent);
2382 -- Legality checks on the address clause for initialized
2383 -- objects is deferred until the freeze point, because
2384 -- a subsequent pragma might indicate that the object is
2385 -- imported and thus not initialized.
2387 Set_Has_Delayed_Freeze (U_Ent);
2389 -- If an initialization call has been generated for this
2390 -- object, it needs to be deferred to after the freeze node
2391 -- we have just now added, otherwise GIGI will see a
2392 -- reference to the variable (as actual to the IP call)
2393 -- before its definition.
2396 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
2398 if Present (Init_Call) then
2400 Append_Freeze_Action (U_Ent, Init_Call);
2404 if Is_Exported (U_Ent) then
2406 ("& cannot be exported if an address clause is given",
2409 ("\define and export a variable " &
2410 "that holds its address instead",
2414 -- Entity has delayed freeze, so we will generate an
2415 -- alignment check at the freeze point unless suppressed.
2417 if not Range_Checks_Suppressed (U_Ent)
2418 and then not Alignment_Checks_Suppressed (U_Ent)
2420 Set_Check_Address_Alignment (N);
2423 -- Kill the size check code, since we are not allocating
2424 -- the variable, it is somewhere else.
2426 Kill_Size_Check_Code (U_Ent);
2428 -- If the address clause is of the form:
2430 -- for Y'Address use X'Address
2434 -- Const : constant Address := X'Address;
2436 -- for Y'Address use Const;
2438 -- then we make an entry in the table for checking the size
2439 -- and alignment of the overlaying variable. We defer this
2440 -- check till after code generation to take full advantage
2441 -- of the annotation done by the back end. This entry is
2442 -- only made if the address clause comes from source.
2444 -- If the entity has a generic type, the check will be
2445 -- performed in the instance if the actual type justifies
2446 -- it, and we do not insert the clause in the table to
2447 -- prevent spurious warnings.
2449 if Address_Clause_Overlay_Warnings
2450 and then Comes_From_Source (N)
2451 and then Present (O_Ent)
2452 and then Is_Object (O_Ent)
2454 if not Is_Generic_Type (Etype (U_Ent)) then
2455 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
2458 -- If variable overlays a constant view, and we are
2459 -- warning on overlays, then mark the variable as
2460 -- overlaying a constant (we will give warnings later
2461 -- if this variable is assigned).
2463 if Is_Constant_Object (O_Ent)
2464 and then Ekind (U_Ent) = E_Variable
2466 Set_Overlays_Constant (U_Ent);
2471 -- Not a valid entity for an address clause
2474 Error_Msg_N ("address cannot be given for &", Nam);
2482 -- Alignment attribute definition clause
2484 when Attribute_Alignment => Alignment : declare
2485 Align : constant Uint := Get_Alignment_Value (Expr);
2490 if not Is_Type (U_Ent)
2491 and then Ekind (U_Ent) /= E_Variable
2492 and then Ekind (U_Ent) /= E_Constant
2494 Error_Msg_N ("alignment cannot be given for &", Nam);
2496 elsif Duplicate_Clause then
2499 elsif Align /= No_Uint then
2500 Set_Has_Alignment_Clause (U_Ent);
2501 Set_Alignment (U_Ent, Align);
2503 -- For an array type, U_Ent is the first subtype. In that case,
2504 -- also set the alignment of the anonymous base type so that
2505 -- other subtypes (such as the itypes for aggregates of the
2506 -- type) also receive the expected alignment.
2508 if Is_Array_Type (U_Ent) then
2509 Set_Alignment (Base_Type (U_Ent), Align);
2518 -- Bit_Order attribute definition clause
2520 when Attribute_Bit_Order => Bit_Order : declare
2522 if not Is_Record_Type (U_Ent) then
2524 ("Bit_Order can only be defined for record type", Nam);
2526 elsif Duplicate_Clause then
2530 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
2532 if Etype (Expr) = Any_Type then
2535 elsif not Is_Static_Expression (Expr) then
2536 Flag_Non_Static_Expr
2537 ("Bit_Order requires static expression!", Expr);
2540 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
2541 Set_Reverse_Bit_Order (U_Ent, True);
2547 --------------------
2548 -- Component_Size --
2549 --------------------
2551 -- Component_Size attribute definition clause
2553 when Attribute_Component_Size => Component_Size_Case : declare
2554 Csize : constant Uint := Static_Integer (Expr);
2558 New_Ctyp : Entity_Id;
2562 if not Is_Array_Type (U_Ent) then
2563 Error_Msg_N ("component size requires array type", Nam);
2567 Btype := Base_Type (U_Ent);
2568 Ctyp := Component_Type (Btype);
2570 if Duplicate_Clause then
2573 elsif Rep_Item_Too_Early (Btype, N) then
2576 elsif Csize /= No_Uint then
2577 Check_Size (Expr, Ctyp, Csize, Biased);
2579 -- For the biased case, build a declaration for a subtype that
2580 -- will be used to represent the biased subtype that reflects
2581 -- the biased representation of components. We need the subtype
2582 -- to get proper conversions on referencing elements of the
2583 -- array. Note: component size clauses are ignored in VM mode.
2585 if VM_Target = No_VM then
2588 Make_Defining_Identifier (Loc,
2590 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2593 Make_Subtype_Declaration (Loc,
2594 Defining_Identifier => New_Ctyp,
2595 Subtype_Indication =>
2596 New_Occurrence_Of (Component_Type (Btype), Loc));
2598 Set_Parent (Decl, N);
2599 Analyze (Decl, Suppress => All_Checks);
2601 Set_Has_Delayed_Freeze (New_Ctyp, False);
2602 Set_Esize (New_Ctyp, Csize);
2603 Set_RM_Size (New_Ctyp, Csize);
2604 Init_Alignment (New_Ctyp);
2605 Set_Is_Itype (New_Ctyp, True);
2606 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2608 Set_Component_Type (Btype, New_Ctyp);
2609 Set_Biased (New_Ctyp, N, "component size clause");
2612 Set_Component_Size (Btype, Csize);
2614 -- For VM case, we ignore component size clauses
2617 -- Give a warning unless we are in GNAT mode, in which case
2618 -- the warning is suppressed since it is not useful.
2620 if not GNAT_Mode then
2622 ("?component size ignored in this configuration", N);
2626 -- Deal with warning on overridden size
2628 if Warn_On_Overridden_Size
2629 and then Has_Size_Clause (Ctyp)
2630 and then RM_Size (Ctyp) /= Csize
2633 ("?component size overrides size clause for&",
2637 Set_Has_Component_Size_Clause (Btype, True);
2638 Set_Has_Non_Standard_Rep (Btype, True);
2640 end Component_Size_Case;
2642 -----------------------
2643 -- Constant_Indexing --
2644 -----------------------
2646 when Attribute_Constant_Indexing =>
2647 Check_Indexing_Functions;
2649 ----------------------
2650 -- Default_Iterator --
2651 ----------------------
2653 when Attribute_Default_Iterator => Default_Iterator : declare
2657 if not Is_Tagged_Type (U_Ent) then
2659 ("aspect Default_Iterator applies to tagged type", Nam);
2662 Check_Iterator_Functions;
2666 if not Is_Entity_Name (Expr)
2667 or else Ekind (Entity (Expr)) /= E_Function
2669 Error_Msg_N ("aspect Iterator must be a function", Expr);
2671 Func := Entity (Expr);
2674 if No (First_Formal (Func))
2675 or else Etype (First_Formal (Func)) /= U_Ent
2678 ("Default Iterator must be a primitive of&", Func, U_Ent);
2680 end Default_Iterator;
2686 when Attribute_External_Tag => External_Tag :
2688 if not Is_Tagged_Type (U_Ent) then
2689 Error_Msg_N ("should be a tagged type", Nam);
2692 if Duplicate_Clause then
2696 Analyze_And_Resolve (Expr, Standard_String);
2698 if not Is_Static_Expression (Expr) then
2699 Flag_Non_Static_Expr
2700 ("static string required for tag name!", Nam);
2703 if VM_Target = No_VM then
2704 Set_Has_External_Tag_Rep_Clause (U_Ent);
2706 Error_Msg_Name_1 := Attr;
2708 ("% attribute unsupported in this configuration", Nam);
2711 if not Is_Library_Level_Entity (U_Ent) then
2713 ("?non-unique external tag supplied for &", N, U_Ent);
2715 ("?\same external tag applies to all subprogram calls", N);
2717 ("?\corresponding internal tag cannot be obtained", N);
2722 --------------------------
2723 -- Implicit_Dereference --
2724 --------------------------
2726 when Attribute_Implicit_Dereference =>
2728 -- Legality checks already performed at the point of
2729 -- the type declaration, aspect is not delayed.
2737 when Attribute_Input =>
2738 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2739 Set_Has_Specified_Stream_Input (Ent);
2741 ----------------------
2742 -- Iterator_Element --
2743 ----------------------
2745 when Attribute_Iterator_Element =>
2748 if not Is_Entity_Name (Expr)
2749 or else not Is_Type (Entity (Expr))
2751 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
2758 -- Machine radix attribute definition clause
2760 when Attribute_Machine_Radix => Machine_Radix : declare
2761 Radix : constant Uint := Static_Integer (Expr);
2764 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2765 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2767 elsif Duplicate_Clause then
2770 elsif Radix /= No_Uint then
2771 Set_Has_Machine_Radix_Clause (U_Ent);
2772 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2776 elsif Radix = 10 then
2777 Set_Machine_Radix_10 (U_Ent);
2779 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2788 -- Object_Size attribute definition clause
2790 when Attribute_Object_Size => Object_Size : declare
2791 Size : constant Uint := Static_Integer (Expr);
2794 pragma Warnings (Off, Biased);
2797 if not Is_Type (U_Ent) then
2798 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2800 elsif Duplicate_Clause then
2804 Check_Size (Expr, U_Ent, Size, Biased);
2812 UI_Mod (Size, 64) /= 0
2815 ("Object_Size must be 8, 16, 32, or multiple of 64",
2819 Set_Esize (U_Ent, Size);
2820 Set_Has_Object_Size_Clause (U_Ent);
2821 Alignment_Check_For_Size_Change (U_Ent, Size);
2829 when Attribute_Output =>
2830 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2831 Set_Has_Specified_Stream_Output (Ent);
2837 when Attribute_Read =>
2838 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2839 Set_Has_Specified_Stream_Read (Ent);
2845 -- Size attribute definition clause
2847 when Attribute_Size => Size : declare
2848 Size : constant Uint := Static_Integer (Expr);
2855 if Duplicate_Clause then
2858 elsif not Is_Type (U_Ent)
2859 and then Ekind (U_Ent) /= E_Variable
2860 and then Ekind (U_Ent) /= E_Constant
2862 Error_Msg_N ("size cannot be given for &", Nam);
2864 elsif Is_Array_Type (U_Ent)
2865 and then not Is_Constrained (U_Ent)
2868 ("size cannot be given for unconstrained array", Nam);
2870 elsif Size /= No_Uint then
2871 if VM_Target /= No_VM and then not GNAT_Mode then
2873 -- Size clause is not handled properly on VM targets.
2874 -- Display a warning unless we are in GNAT mode, in which
2875 -- case this is useless.
2878 ("?size clauses are ignored in this configuration", N);
2881 if Is_Type (U_Ent) then
2884 Etyp := Etype (U_Ent);
2887 -- Check size, note that Gigi is in charge of checking that the
2888 -- size of an array or record type is OK. Also we do not check
2889 -- the size in the ordinary fixed-point case, since it is too
2890 -- early to do so (there may be subsequent small clause that
2891 -- affects the size). We can check the size if a small clause
2892 -- has already been given.
2894 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2895 or else Has_Small_Clause (U_Ent)
2897 Check_Size (Expr, Etyp, Size, Biased);
2898 Set_Biased (U_Ent, N, "size clause", Biased);
2901 -- For types set RM_Size and Esize if possible
2903 if Is_Type (U_Ent) then
2904 Set_RM_Size (U_Ent, Size);
2906 -- For elementary types, increase Object_Size to power of 2,
2907 -- but not less than a storage unit in any case (normally
2908 -- this means it will be byte addressable).
2910 -- For all other types, nothing else to do, we leave Esize
2911 -- (object size) unset, the back end will set it from the
2912 -- size and alignment in an appropriate manner.
2914 -- In both cases, we check whether the alignment must be
2915 -- reset in the wake of the size change.
2917 if Is_Elementary_Type (U_Ent) then
2918 if Size <= System_Storage_Unit then
2919 Init_Esize (U_Ent, System_Storage_Unit);
2920 elsif Size <= 16 then
2921 Init_Esize (U_Ent, 16);
2922 elsif Size <= 32 then
2923 Init_Esize (U_Ent, 32);
2925 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2928 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
2930 Alignment_Check_For_Size_Change (U_Ent, Size);
2933 -- For objects, set Esize only
2936 if Is_Elementary_Type (Etyp) then
2937 if Size /= System_Storage_Unit
2939 Size /= System_Storage_Unit * 2
2941 Size /= System_Storage_Unit * 4
2943 Size /= System_Storage_Unit * 8
2945 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2946 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2948 ("size for primitive object must be a power of 2"
2949 & " in the range ^-^", N);
2953 Set_Esize (U_Ent, Size);
2956 Set_Has_Size_Clause (U_Ent);
2964 -- Small attribute definition clause
2966 when Attribute_Small => Small : declare
2967 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2971 Analyze_And_Resolve (Expr, Any_Real);
2973 if Etype (Expr) = Any_Type then
2976 elsif not Is_Static_Expression (Expr) then
2977 Flag_Non_Static_Expr
2978 ("small requires static expression!", Expr);
2982 Small := Expr_Value_R (Expr);
2984 if Small <= Ureal_0 then
2985 Error_Msg_N ("small value must be greater than zero", Expr);
2991 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2993 ("small requires an ordinary fixed point type", Nam);
2995 elsif Has_Small_Clause (U_Ent) then
2996 Error_Msg_N ("small already given for &", Nam);
2998 elsif Small > Delta_Value (U_Ent) then
3000 ("small value must not be greater then delta value", Nam);
3003 Set_Small_Value (U_Ent, Small);
3004 Set_Small_Value (Implicit_Base, Small);
3005 Set_Has_Small_Clause (U_Ent);
3006 Set_Has_Small_Clause (Implicit_Base);
3007 Set_Has_Non_Standard_Rep (Implicit_Base);
3015 -- Storage_Pool attribute definition clause
3017 when Attribute_Storage_Pool => Storage_Pool : declare
3022 if Ekind (U_Ent) = E_Access_Subprogram_Type then
3024 ("storage pool cannot be given for access-to-subprogram type",
3029 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
3032 ("storage pool can only be given for access types", Nam);
3035 elsif Is_Derived_Type (U_Ent) then
3037 ("storage pool cannot be given for a derived access type",
3040 elsif Duplicate_Clause then
3043 elsif Present (Associated_Storage_Pool (U_Ent)) then
3044 Error_Msg_N ("storage pool already given for &", Nam);
3049 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
3051 if not Denotes_Variable (Expr) then
3052 Error_Msg_N ("storage pool must be a variable", Expr);
3056 if Nkind (Expr) = N_Type_Conversion then
3057 T := Etype (Expression (Expr));
3062 -- The Stack_Bounded_Pool is used internally for implementing
3063 -- access types with a Storage_Size. Since it only work properly
3064 -- when used on one specific type, we need to check that it is not
3065 -- hijacked improperly:
3067 -- type T is access Integer;
3068 -- for T'Storage_Size use n;
3069 -- type Q is access Float;
3070 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
3072 if RTE_Available (RE_Stack_Bounded_Pool)
3073 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
3075 Error_Msg_N ("non-shareable internal Pool", Expr);
3079 -- If the argument is a name that is not an entity name, then
3080 -- we construct a renaming operation to define an entity of
3081 -- type storage pool.
3083 if not Is_Entity_Name (Expr)
3084 and then Is_Object_Reference (Expr)
3086 Pool := Make_Temporary (Loc, 'P', Expr);
3089 Rnode : constant Node_Id :=
3090 Make_Object_Renaming_Declaration (Loc,
3091 Defining_Identifier => Pool,
3093 New_Occurrence_Of (Etype (Expr), Loc),
3097 Insert_Before (N, Rnode);
3099 Set_Associated_Storage_Pool (U_Ent, Pool);
3102 elsif Is_Entity_Name (Expr) then
3103 Pool := Entity (Expr);
3105 -- If pool is a renamed object, get original one. This can
3106 -- happen with an explicit renaming, and within instances.
3108 while Present (Renamed_Object (Pool))
3109 and then Is_Entity_Name (Renamed_Object (Pool))
3111 Pool := Entity (Renamed_Object (Pool));
3114 if Present (Renamed_Object (Pool))
3115 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
3116 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
3118 Pool := Entity (Expression (Renamed_Object (Pool)));
3121 Set_Associated_Storage_Pool (U_Ent, Pool);
3123 elsif Nkind (Expr) = N_Type_Conversion
3124 and then Is_Entity_Name (Expression (Expr))
3125 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
3127 Pool := Entity (Expression (Expr));
3128 Set_Associated_Storage_Pool (U_Ent, Pool);
3131 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
3140 -- Storage_Size attribute definition clause
3142 when Attribute_Storage_Size => Storage_Size : declare
3143 Btype : constant Entity_Id := Base_Type (U_Ent);
3147 if Is_Task_Type (U_Ent) then
3148 Check_Restriction (No_Obsolescent_Features, N);
3150 if Warn_On_Obsolescent_Feature then
3152 ("storage size clause for task is an " &
3153 "obsolescent feature (RM J.9)?", N);
3154 Error_Msg_N ("\use Storage_Size pragma instead?", N);
3160 if not Is_Access_Type (U_Ent)
3161 and then Ekind (U_Ent) /= E_Task_Type
3163 Error_Msg_N ("storage size cannot be given for &", Nam);
3165 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
3167 ("storage size cannot be given for a derived access type",
3170 elsif Duplicate_Clause then
3174 Analyze_And_Resolve (Expr, Any_Integer);
3176 if Is_Access_Type (U_Ent) then
3177 if Present (Associated_Storage_Pool (U_Ent)) then
3178 Error_Msg_N ("storage pool already given for &", Nam);
3182 if Is_OK_Static_Expression (Expr)
3183 and then Expr_Value (Expr) = 0
3185 Set_No_Pool_Assigned (Btype);
3188 else -- Is_Task_Type (U_Ent)
3189 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
3191 if Present (Sprag) then
3192 Error_Msg_Sloc := Sloc (Sprag);
3194 ("Storage_Size already specified#", Nam);
3199 Set_Has_Storage_Size_Clause (Btype);
3207 when Attribute_Stream_Size => Stream_Size : declare
3208 Size : constant Uint := Static_Integer (Expr);
3211 if Ada_Version <= Ada_95 then
3212 Check_Restriction (No_Implementation_Attributes, N);
3215 if Duplicate_Clause then
3218 elsif Is_Elementary_Type (U_Ent) then
3219 if Size /= System_Storage_Unit
3221 Size /= System_Storage_Unit * 2
3223 Size /= System_Storage_Unit * 4
3225 Size /= System_Storage_Unit * 8
3227 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
3229 ("stream size for elementary type must be a"
3230 & " power of 2 and at least ^", N);
3232 elsif RM_Size (U_Ent) > Size then
3233 Error_Msg_Uint_1 := RM_Size (U_Ent);
3235 ("stream size for elementary type must be a"
3236 & " power of 2 and at least ^", N);
3239 Set_Has_Stream_Size_Clause (U_Ent);
3242 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
3250 -- Value_Size attribute definition clause
3252 when Attribute_Value_Size => Value_Size : declare
3253 Size : constant Uint := Static_Integer (Expr);
3257 if not Is_Type (U_Ent) then
3258 Error_Msg_N ("Value_Size cannot be given for &", Nam);
3260 elsif Duplicate_Clause then
3263 elsif Is_Array_Type (U_Ent)
3264 and then not Is_Constrained (U_Ent)
3267 ("Value_Size cannot be given for unconstrained array", Nam);
3270 if Is_Elementary_Type (U_Ent) then
3271 Check_Size (Expr, U_Ent, Size, Biased);
3272 Set_Biased (U_Ent, N, "value size clause", Biased);
3275 Set_RM_Size (U_Ent, Size);
3279 -----------------------
3280 -- Variable_Indexing --
3281 -----------------------
3283 when Attribute_Variable_Indexing =>
3284 Check_Indexing_Functions;
3290 when Attribute_Write =>
3291 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
3292 Set_Has_Specified_Stream_Write (Ent);
3294 -- All other attributes cannot be set
3298 ("attribute& cannot be set with definition clause", N);
3301 -- The test for the type being frozen must be performed after any
3302 -- expression the clause has been analyzed since the expression itself
3303 -- might cause freezing that makes the clause illegal.
3305 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
3308 end Analyze_Attribute_Definition_Clause;
3310 ----------------------------
3311 -- Analyze_Code_Statement --
3312 ----------------------------
3314 procedure Analyze_Code_Statement (N : Node_Id) is
3315 HSS : constant Node_Id := Parent (N);
3316 SBody : constant Node_Id := Parent (HSS);
3317 Subp : constant Entity_Id := Current_Scope;
3324 -- Analyze and check we get right type, note that this implements the
3325 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
3326 -- is the only way that Asm_Insn could possibly be visible.
3328 Analyze_And_Resolve (Expression (N));
3330 if Etype (Expression (N)) = Any_Type then
3332 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
3333 Error_Msg_N ("incorrect type for code statement", N);
3337 Check_Code_Statement (N);
3339 -- Make sure we appear in the handled statement sequence of a
3340 -- subprogram (RM 13.8(3)).
3342 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
3343 or else Nkind (SBody) /= N_Subprogram_Body
3346 ("code statement can only appear in body of subprogram", N);
3350 -- Do remaining checks (RM 13.8(3)) if not already done
3352 if not Is_Machine_Code_Subprogram (Subp) then
3353 Set_Is_Machine_Code_Subprogram (Subp);
3355 -- No exception handlers allowed
3357 if Present (Exception_Handlers (HSS)) then
3359 ("exception handlers not permitted in machine code subprogram",
3360 First (Exception_Handlers (HSS)));
3363 -- No declarations other than use clauses and pragmas (we allow
3364 -- certain internally generated declarations as well).
3366 Decl := First (Declarations (SBody));
3367 while Present (Decl) loop
3368 DeclO := Original_Node (Decl);
3369 if Comes_From_Source (DeclO)
3370 and not Nkind_In (DeclO, N_Pragma,
3371 N_Use_Package_Clause,
3373 N_Implicit_Label_Declaration)
3376 ("this declaration not allowed in machine code subprogram",
3383 -- No statements other than code statements, pragmas, and labels.
3384 -- Again we allow certain internally generated statements.
3386 -- In Ada 2012, qualified expressions are names, and the code
3387 -- statement is initially parsed as a procedure call.
3389 Stmt := First (Statements (HSS));
3390 while Present (Stmt) loop
3391 StmtO := Original_Node (Stmt);
3393 -- A procedure call transformed into a code statement is OK.
3395 if Ada_Version >= Ada_2012
3396 and then Nkind (StmtO) = N_Procedure_Call_Statement
3397 and then Nkind (Name (StmtO)) = N_Qualified_Expression
3401 elsif Comes_From_Source (StmtO)
3402 and then not Nkind_In (StmtO, N_Pragma,
3407 ("this statement is not allowed in machine code subprogram",
3414 end Analyze_Code_Statement;
3416 -----------------------------------------------
3417 -- Analyze_Enumeration_Representation_Clause --
3418 -----------------------------------------------
3420 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
3421 Ident : constant Node_Id := Identifier (N);
3422 Aggr : constant Node_Id := Array_Aggregate (N);
3423 Enumtype : Entity_Id;
3430 Err : Boolean := False;
3431 -- Set True to avoid cascade errors and crashes on incorrect source code
3433 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
3434 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
3435 -- Allowed range of universal integer (= allowed range of enum lit vals)
3439 -- Minimum and maximum values of entries
3442 -- Pointer to node for literal providing max value
3445 if Ignore_Rep_Clauses then
3449 -- First some basic error checks
3452 Enumtype := Entity (Ident);
3454 if Enumtype = Any_Type
3455 or else Rep_Item_Too_Early (Enumtype, N)
3459 Enumtype := Underlying_Type (Enumtype);
3462 if not Is_Enumeration_Type (Enumtype) then
3464 ("enumeration type required, found}",
3465 Ident, First_Subtype (Enumtype));
3469 -- Ignore rep clause on generic actual type. This will already have
3470 -- been flagged on the template as an error, and this is the safest
3471 -- way to ensure we don't get a junk cascaded message in the instance.
3473 if Is_Generic_Actual_Type (Enumtype) then
3476 -- Type must be in current scope
3478 elsif Scope (Enumtype) /= Current_Scope then
3479 Error_Msg_N ("type must be declared in this scope", Ident);
3482 -- Type must be a first subtype
3484 elsif not Is_First_Subtype (Enumtype) then
3485 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
3488 -- Ignore duplicate rep clause
3490 elsif Has_Enumeration_Rep_Clause (Enumtype) then
3491 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
3494 -- Don't allow rep clause for standard [wide_[wide_]]character
3496 elsif Is_Standard_Character_Type (Enumtype) then
3497 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
3500 -- Check that the expression is a proper aggregate (no parentheses)
3502 elsif Paren_Count (Aggr) /= 0 then
3504 ("extra parentheses surrounding aggregate not allowed",
3508 -- All tests passed, so set rep clause in place
3511 Set_Has_Enumeration_Rep_Clause (Enumtype);
3512 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
3515 -- Now we process the aggregate. Note that we don't use the normal
3516 -- aggregate code for this purpose, because we don't want any of the
3517 -- normal expansion activities, and a number of special semantic
3518 -- rules apply (including the component type being any integer type)
3520 Elit := First_Literal (Enumtype);
3522 -- First the positional entries if any
3524 if Present (Expressions (Aggr)) then
3525 Expr := First (Expressions (Aggr));
3526 while Present (Expr) loop
3528 Error_Msg_N ("too many entries in aggregate", Expr);
3532 Val := Static_Integer (Expr);
3534 -- Err signals that we found some incorrect entries processing
3535 -- the list. The final checks for completeness and ordering are
3536 -- skipped in this case.
3538 if Val = No_Uint then
3540 elsif Val < Lo or else Hi < Val then
3541 Error_Msg_N ("value outside permitted range", Expr);
3545 Set_Enumeration_Rep (Elit, Val);
3546 Set_Enumeration_Rep_Expr (Elit, Expr);
3552 -- Now process the named entries if present
3554 if Present (Component_Associations (Aggr)) then
3555 Assoc := First (Component_Associations (Aggr));
3556 while Present (Assoc) loop
3557 Choice := First (Choices (Assoc));
3559 if Present (Next (Choice)) then
3561 ("multiple choice not allowed here", Next (Choice));
3565 if Nkind (Choice) = N_Others_Choice then
3566 Error_Msg_N ("others choice not allowed here", Choice);
3569 elsif Nkind (Choice) = N_Range then
3571 -- ??? should allow zero/one element range here
3573 Error_Msg_N ("range not allowed here", Choice);
3577 Analyze_And_Resolve (Choice, Enumtype);
3579 if Error_Posted (Choice) then
3584 if Is_Entity_Name (Choice)
3585 and then Is_Type (Entity (Choice))
3587 Error_Msg_N ("subtype name not allowed here", Choice);
3590 -- ??? should allow static subtype with zero/one entry
3592 elsif Etype (Choice) = Base_Type (Enumtype) then
3593 if not Is_Static_Expression (Choice) then
3594 Flag_Non_Static_Expr
3595 ("non-static expression used for choice!", Choice);
3599 Elit := Expr_Value_E (Choice);
3601 if Present (Enumeration_Rep_Expr (Elit)) then
3603 Sloc (Enumeration_Rep_Expr (Elit));
3605 ("representation for& previously given#",
3610 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
3612 Expr := Expression (Assoc);
3613 Val := Static_Integer (Expr);
3615 if Val = No_Uint then
3618 elsif Val < Lo or else Hi < Val then
3619 Error_Msg_N ("value outside permitted range", Expr);
3623 Set_Enumeration_Rep (Elit, Val);
3633 -- Aggregate is fully processed. Now we check that a full set of
3634 -- representations was given, and that they are in range and in order.
3635 -- These checks are only done if no other errors occurred.
3641 Elit := First_Literal (Enumtype);
3642 while Present (Elit) loop
3643 if No (Enumeration_Rep_Expr (Elit)) then
3644 Error_Msg_NE ("missing representation for&!", N, Elit);
3647 Val := Enumeration_Rep (Elit);
3649 if Min = No_Uint then
3653 if Val /= No_Uint then
3654 if Max /= No_Uint and then Val <= Max then
3656 ("enumeration value for& not ordered!",
3657 Enumeration_Rep_Expr (Elit), Elit);
3660 Max_Node := Enumeration_Rep_Expr (Elit);
3664 -- If there is at least one literal whose representation is not
3665 -- equal to the Pos value, then note that this enumeration type
3666 -- has a non-standard representation.
3668 if Val /= Enumeration_Pos (Elit) then
3669 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3676 -- Now set proper size information
3679 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3682 if Has_Size_Clause (Enumtype) then
3684 -- All OK, if size is OK now
3686 if RM_Size (Enumtype) >= Minsize then
3690 -- Try if we can get by with biasing
3693 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3695 -- Error message if even biasing does not work
3697 if RM_Size (Enumtype) < Minsize then
3698 Error_Msg_Uint_1 := RM_Size (Enumtype);
3699 Error_Msg_Uint_2 := Max;
3701 ("previously given size (^) is too small "
3702 & "for this value (^)", Max_Node);
3704 -- If biasing worked, indicate that we now have biased rep
3708 (Enumtype, Size_Clause (Enumtype), "size clause");
3713 Set_RM_Size (Enumtype, Minsize);
3714 Set_Enum_Esize (Enumtype);
3717 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3718 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3719 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3723 -- We repeat the too late test in case it froze itself!
3725 if Rep_Item_Too_Late (Enumtype, N) then
3728 end Analyze_Enumeration_Representation_Clause;
3730 ----------------------------
3731 -- Analyze_Free_Statement --
3732 ----------------------------
3734 procedure Analyze_Free_Statement (N : Node_Id) is
3736 Analyze (Expression (N));
3737 end Analyze_Free_Statement;
3739 ---------------------------
3740 -- Analyze_Freeze_Entity --
3741 ---------------------------
3743 procedure Analyze_Freeze_Entity (N : Node_Id) is
3744 E : constant Entity_Id := Entity (N);
3747 -- Remember that we are processing a freezing entity. Required to
3748 -- ensure correct decoration of internal entities associated with
3749 -- interfaces (see New_Overloaded_Entity).
3751 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3753 -- For tagged types covering interfaces add internal entities that link
3754 -- the primitives of the interfaces with the primitives that cover them.
3755 -- Note: These entities were originally generated only when generating
3756 -- code because their main purpose was to provide support to initialize
3757 -- the secondary dispatch tables. They are now generated also when
3758 -- compiling with no code generation to provide ASIS the relationship
3759 -- between interface primitives and tagged type primitives. They are
3760 -- also used to locate primitives covering interfaces when processing
3761 -- generics (see Derive_Subprograms).
3763 if Ada_Version >= Ada_2005
3764 and then Ekind (E) = E_Record_Type
3765 and then Is_Tagged_Type (E)
3766 and then not Is_Interface (E)
3767 and then Has_Interfaces (E)
3769 -- This would be a good common place to call the routine that checks
3770 -- overriding of interface primitives (and thus factorize calls to
3771 -- Check_Abstract_Overriding located at different contexts in the
3772 -- compiler). However, this is not possible because it causes
3773 -- spurious errors in case of late overriding.
3775 Add_Internal_Interface_Entities (E);
3780 if Ekind (E) = E_Record_Type
3781 and then Is_CPP_Class (E)
3782 and then Is_Tagged_Type (E)
3783 and then Tagged_Type_Expansion
3784 and then Expander_Active
3786 if CPP_Num_Prims (E) = 0 then
3788 -- If the CPP type has user defined components then it must import
3789 -- primitives from C++. This is required because if the C++ class
3790 -- has no primitives then the C++ compiler does not added the _tag
3791 -- component to the type.
3793 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3795 if First_Entity (E) /= Last_Entity (E) then
3797 ("?'C'P'P type must import at least one primitive from C++",
3802 -- Check that all its primitives are abstract or imported from C++.
3803 -- Check also availability of the C++ constructor.
3806 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3808 Error_Reported : Boolean := False;
3812 Elmt := First_Elmt (Primitive_Operations (E));
3813 while Present (Elmt) loop
3814 Prim := Node (Elmt);
3816 if Comes_From_Source (Prim) then
3817 if Is_Abstract_Subprogram (Prim) then
3820 elsif not Is_Imported (Prim)
3821 or else Convention (Prim) /= Convention_CPP
3824 ("?primitives of 'C'P'P types must be imported from C++"
3825 & " or abstract", Prim);
3827 elsif not Has_Constructors
3828 and then not Error_Reported
3830 Error_Msg_Name_1 := Chars (E);
3832 ("?'C'P'P constructor required for type %", Prim);
3833 Error_Reported := True;
3842 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3844 -- If we have a type with predicates, build predicate function
3846 if Is_Type (E) and then Has_Predicates (E) then
3847 Build_Predicate_Function (E, N);
3850 -- If type has delayed aspects, this is where we do the preanalysis at
3851 -- the freeze point, as part of the consistent visibility check. Note
3852 -- that this must be done after calling Build_Predicate_Function or
3853 -- Build_Invariant_Procedure since these subprograms fix occurrences of
3854 -- the subtype name in the saved expression so that they will not cause
3855 -- trouble in the preanalysis.
3857 if Has_Delayed_Aspects (E) then
3862 -- Look for aspect specification entries for this entity
3864 Ritem := First_Rep_Item (E);
3865 while Present (Ritem) loop
3866 if Nkind (Ritem) = N_Aspect_Specification
3867 and then Entity (Ritem) = E
3868 and then Is_Delayed_Aspect (Ritem)
3869 and then Scope (E) = Current_Scope
3871 Check_Aspect_At_Freeze_Point (Ritem);
3874 Next_Rep_Item (Ritem);
3878 end Analyze_Freeze_Entity;
3880 ------------------------------------------
3881 -- Analyze_Record_Representation_Clause --
3882 ------------------------------------------
3884 -- Note: we check as much as we can here, but we can't do any checks
3885 -- based on the position values (e.g. overlap checks) until freeze time
3886 -- because especially in Ada 2005 (machine scalar mode), the processing
3887 -- for non-standard bit order can substantially change the positions.
3888 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3889 -- for the remainder of this processing.
3891 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3892 Ident : constant Node_Id := Identifier (N);
3897 Hbit : Uint := Uint_0;
3901 Rectype : Entity_Id;
3903 CR_Pragma : Node_Id := Empty;
3904 -- Points to N_Pragma node if Complete_Representation pragma present
3907 if Ignore_Rep_Clauses then
3912 Rectype := Entity (Ident);
3914 if Rectype = Any_Type
3915 or else Rep_Item_Too_Early (Rectype, N)
3919 Rectype := Underlying_Type (Rectype);
3922 -- First some basic error checks
3924 if not Is_Record_Type (Rectype) then
3926 ("record type required, found}", Ident, First_Subtype (Rectype));
3929 elsif Scope (Rectype) /= Current_Scope then
3930 Error_Msg_N ("type must be declared in this scope", N);
3933 elsif not Is_First_Subtype (Rectype) then
3934 Error_Msg_N ("cannot give record rep clause for subtype", N);
3937 elsif Has_Record_Rep_Clause (Rectype) then
3938 Error_Msg_N ("duplicate record rep clause ignored", N);
3941 elsif Rep_Item_Too_Late (Rectype, N) then
3945 if Present (Mod_Clause (N)) then
3947 Loc : constant Source_Ptr := Sloc (N);
3948 M : constant Node_Id := Mod_Clause (N);
3949 P : constant List_Id := Pragmas_Before (M);
3953 pragma Warnings (Off, Mod_Val);
3956 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3958 if Warn_On_Obsolescent_Feature then
3960 ("mod clause is an obsolescent feature (RM J.8)?", N);
3962 ("\use alignment attribute definition clause instead?", N);
3969 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3970 -- the Mod clause into an alignment clause anyway, so that the
3971 -- back-end can compute and back-annotate properly the size and
3972 -- alignment of types that may include this record.
3974 -- This seems dubious, this destroys the source tree in a manner
3975 -- not detectable by ASIS ???
3977 if Operating_Mode = Check_Semantics and then ASIS_Mode then
3979 Make_Attribute_Definition_Clause (Loc,
3980 Name => New_Reference_To (Base_Type (Rectype), Loc),
3981 Chars => Name_Alignment,
3982 Expression => Relocate_Node (Expression (M)));
3984 Set_From_At_Mod (AtM_Nod);
3985 Insert_After (N, AtM_Nod);
3986 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3987 Set_Mod_Clause (N, Empty);
3990 -- Get the alignment value to perform error checking
3992 Mod_Val := Get_Alignment_Value (Expression (M));
3997 -- For untagged types, clear any existing component clauses for the
3998 -- type. If the type is derived, this is what allows us to override
3999 -- a rep clause for the parent. For type extensions, the representation
4000 -- of the inherited components is inherited, so we want to keep previous
4001 -- component clauses for completeness.
4003 if not Is_Tagged_Type (Rectype) then
4004 Comp := First_Component_Or_Discriminant (Rectype);
4005 while Present (Comp) loop
4006 Set_Component_Clause (Comp, Empty);
4007 Next_Component_Or_Discriminant (Comp);
4011 -- All done if no component clauses
4013 CC := First (Component_Clauses (N));
4019 -- A representation like this applies to the base type
4021 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
4022 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
4023 Set_Has_Specified_Layout (Base_Type (Rectype));
4025 -- Process the component clauses
4027 while Present (CC) loop
4031 if Nkind (CC) = N_Pragma then
4034 -- The only pragma of interest is Complete_Representation
4036 if Pragma_Name (CC) = Name_Complete_Representation then
4040 -- Processing for real component clause
4043 Posit := Static_Integer (Position (CC));
4044 Fbit := Static_Integer (First_Bit (CC));
4045 Lbit := Static_Integer (Last_Bit (CC));
4048 and then Fbit /= No_Uint
4049 and then Lbit /= No_Uint
4053 ("position cannot be negative", Position (CC));
4057 ("first bit cannot be negative", First_Bit (CC));
4059 -- The Last_Bit specified in a component clause must not be
4060 -- less than the First_Bit minus one (RM-13.5.1(10)).
4062 elsif Lbit < Fbit - 1 then
4064 ("last bit cannot be less than first bit minus one",
4067 -- Values look OK, so find the corresponding record component
4068 -- Even though the syntax allows an attribute reference for
4069 -- implementation-defined components, GNAT does not allow the
4070 -- tag to get an explicit position.
4072 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
4073 if Attribute_Name (Component_Name (CC)) = Name_Tag then
4074 Error_Msg_N ("position of tag cannot be specified", CC);
4076 Error_Msg_N ("illegal component name", CC);
4080 Comp := First_Entity (Rectype);
4081 while Present (Comp) loop
4082 exit when Chars (Comp) = Chars (Component_Name (CC));
4088 -- Maybe component of base type that is absent from
4089 -- statically constrained first subtype.
4091 Comp := First_Entity (Base_Type (Rectype));
4092 while Present (Comp) loop
4093 exit when Chars (Comp) = Chars (Component_Name (CC));
4100 ("component clause is for non-existent field", CC);
4102 -- Ada 2012 (AI05-0026): Any name that denotes a
4103 -- discriminant of an object of an unchecked union type
4104 -- shall not occur within a record_representation_clause.
4106 -- The general restriction of using record rep clauses on
4107 -- Unchecked_Union types has now been lifted. Since it is
4108 -- possible to introduce a record rep clause which mentions
4109 -- the discriminant of an Unchecked_Union in non-Ada 2012
4110 -- code, this check is applied to all versions of the
4113 elsif Ekind (Comp) = E_Discriminant
4114 and then Is_Unchecked_Union (Rectype)
4117 ("cannot reference discriminant of Unchecked_Union",
4118 Component_Name (CC));
4120 elsif Present (Component_Clause (Comp)) then
4122 -- Diagnose duplicate rep clause, or check consistency
4123 -- if this is an inherited component. In a double fault,
4124 -- there may be a duplicate inconsistent clause for an
4125 -- inherited component.
4127 if Scope (Original_Record_Component (Comp)) = Rectype
4128 or else Parent (Component_Clause (Comp)) = N
4130 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
4131 Error_Msg_N ("component clause previously given#", CC);
4135 Rep1 : constant Node_Id := Component_Clause (Comp);
4137 if Intval (Position (Rep1)) /=
4138 Intval (Position (CC))
4139 or else Intval (First_Bit (Rep1)) /=
4140 Intval (First_Bit (CC))
4141 or else Intval (Last_Bit (Rep1)) /=
4142 Intval (Last_Bit (CC))
4144 Error_Msg_N ("component clause inconsistent "
4145 & "with representation of ancestor", CC);
4146 elsif Warn_On_Redundant_Constructs then
4147 Error_Msg_N ("?redundant component clause "
4148 & "for inherited component!", CC);
4153 -- Normal case where this is the first component clause we
4154 -- have seen for this entity, so set it up properly.
4157 -- Make reference for field in record rep clause and set
4158 -- appropriate entity field in the field identifier.
4161 (Comp, Component_Name (CC), Set_Ref => False);
4162 Set_Entity (Component_Name (CC), Comp);
4164 -- Update Fbit and Lbit to the actual bit number
4166 Fbit := Fbit + UI_From_Int (SSU) * Posit;
4167 Lbit := Lbit + UI_From_Int (SSU) * Posit;
4169 if Has_Size_Clause (Rectype)
4170 and then RM_Size (Rectype) <= Lbit
4173 ("bit number out of range of specified size",
4176 Set_Component_Clause (Comp, CC);
4177 Set_Component_Bit_Offset (Comp, Fbit);
4178 Set_Esize (Comp, 1 + (Lbit - Fbit));
4179 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
4180 Set_Normalized_Position (Comp, Fbit / SSU);
4182 if Warn_On_Overridden_Size
4183 and then Has_Size_Clause (Etype (Comp))
4184 and then RM_Size (Etype (Comp)) /= Esize (Comp)
4187 ("?component size overrides size clause for&",
4188 Component_Name (CC), Etype (Comp));
4191 -- This information is also set in the corresponding
4192 -- component of the base type, found by accessing the
4193 -- Original_Record_Component link if it is present.
4195 Ocomp := Original_Record_Component (Comp);
4202 (Component_Name (CC),
4208 (Comp, First_Node (CC), "component clause", Biased);
4210 if Present (Ocomp) then
4211 Set_Component_Clause (Ocomp, CC);
4212 Set_Component_Bit_Offset (Ocomp, Fbit);
4213 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
4214 Set_Normalized_Position (Ocomp, Fbit / SSU);
4215 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
4217 Set_Normalized_Position_Max
4218 (Ocomp, Normalized_Position (Ocomp));
4220 -- Note: we don't use Set_Biased here, because we
4221 -- already gave a warning above if needed, and we
4222 -- would get a duplicate for the same name here.
4224 Set_Has_Biased_Representation
4225 (Ocomp, Has_Biased_Representation (Comp));
4228 if Esize (Comp) < 0 then
4229 Error_Msg_N ("component size is negative", CC);
4240 -- Check missing components if Complete_Representation pragma appeared
4242 if Present (CR_Pragma) then
4243 Comp := First_Component_Or_Discriminant (Rectype);
4244 while Present (Comp) loop
4245 if No (Component_Clause (Comp)) then
4247 ("missing component clause for &", CR_Pragma, Comp);
4250 Next_Component_Or_Discriminant (Comp);
4253 -- If no Complete_Representation pragma, warn if missing components
4255 elsif Warn_On_Unrepped_Components then
4257 Num_Repped_Components : Nat := 0;
4258 Num_Unrepped_Components : Nat := 0;
4261 -- First count number of repped and unrepped components
4263 Comp := First_Component_Or_Discriminant (Rectype);
4264 while Present (Comp) loop
4265 if Present (Component_Clause (Comp)) then
4266 Num_Repped_Components := Num_Repped_Components + 1;
4268 Num_Unrepped_Components := Num_Unrepped_Components + 1;
4271 Next_Component_Or_Discriminant (Comp);
4274 -- We are only interested in the case where there is at least one
4275 -- unrepped component, and at least half the components have rep
4276 -- clauses. We figure that if less than half have them, then the
4277 -- partial rep clause is really intentional. If the component
4278 -- type has no underlying type set at this point (as for a generic
4279 -- formal type), we don't know enough to give a warning on the
4282 if Num_Unrepped_Components > 0
4283 and then Num_Unrepped_Components < Num_Repped_Components
4285 Comp := First_Component_Or_Discriminant (Rectype);
4286 while Present (Comp) loop
4287 if No (Component_Clause (Comp))
4288 and then Comes_From_Source (Comp)
4289 and then Present (Underlying_Type (Etype (Comp)))
4290 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
4291 or else Size_Known_At_Compile_Time
4292 (Underlying_Type (Etype (Comp))))
4293 and then not Has_Warnings_Off (Rectype)
4295 Error_Msg_Sloc := Sloc (Comp);
4297 ("?no component clause given for & declared #",
4301 Next_Component_Or_Discriminant (Comp);
4306 end Analyze_Record_Representation_Clause;
4308 -------------------------------
4309 -- Build_Invariant_Procedure --
4310 -------------------------------
4312 -- The procedure that is constructed here has the form
4314 -- procedure typInvariant (Ixxx : typ) is
4316 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4317 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4319 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
4321 -- end typInvariant;
4323 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
4324 Loc : constant Source_Ptr := Sloc (Typ);
4331 Visible_Decls : constant List_Id := Visible_Declarations (N);
4332 Private_Decls : constant List_Id := Private_Declarations (N);
4334 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
4335 -- Appends statements to Stmts for any invariants in the rep item chain
4336 -- of the given type. If Inherit is False, then we only process entries
4337 -- on the chain for the type Typ. If Inherit is True, then we ignore any
4338 -- Invariant aspects, but we process all Invariant'Class aspects, adding
4339 -- "inherited" to the exception message and generating an informational
4340 -- message about the inheritance of an invariant.
4342 Object_Name : constant Name_Id := New_Internal_Name ('I');
4343 -- Name for argument of invariant procedure
4345 Object_Entity : constant Node_Id :=
4346 Make_Defining_Identifier (Loc, Object_Name);
4347 -- The procedure declaration entity for the argument
4349 --------------------
4350 -- Add_Invariants --
4351 --------------------
4353 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
4363 procedure Replace_Type_Reference (N : Node_Id);
4364 -- Replace a single occurrence N of the subtype name with a reference
4365 -- to the formal of the predicate function. N can be an identifier
4366 -- referencing the subtype, or a selected component, representing an
4367 -- appropriately qualified occurrence of the subtype name.
4369 procedure Replace_Type_References is
4370 new Replace_Type_References_Generic (Replace_Type_Reference);
4371 -- Traverse an expression replacing all occurrences of the subtype
4372 -- name with appropriate references to the object that is the formal
4373 -- parameter of the predicate function. Note that we must ensure
4374 -- that the type and entity information is properly set in the
4375 -- replacement node, since we will do a Preanalyze call of this
4376 -- expression without proper visibility of the procedure argument.
4378 ----------------------------
4379 -- Replace_Type_Reference --
4380 ----------------------------
4382 procedure Replace_Type_Reference (N : Node_Id) is
4384 -- Invariant'Class, replace with T'Class (obj)
4386 if Class_Present (Ritem) then
4388 Make_Type_Conversion (Loc,
4390 Make_Attribute_Reference (Loc,
4391 Prefix => New_Occurrence_Of (T, Loc),
4392 Attribute_Name => Name_Class),
4393 Expression => Make_Identifier (Loc, Object_Name)));
4395 Set_Entity (Expression (N), Object_Entity);
4396 Set_Etype (Expression (N), Typ);
4398 -- Invariant, replace with obj
4401 Rewrite (N, Make_Identifier (Loc, Object_Name));
4402 Set_Entity (N, Object_Entity);
4405 end Replace_Type_Reference;
4407 -- Start of processing for Add_Invariants
4410 Ritem := First_Rep_Item (T);
4411 while Present (Ritem) loop
4412 if Nkind (Ritem) = N_Pragma
4413 and then Pragma_Name (Ritem) = Name_Invariant
4415 Arg1 := First (Pragma_Argument_Associations (Ritem));
4416 Arg2 := Next (Arg1);
4417 Arg3 := Next (Arg2);
4419 Arg1 := Get_Pragma_Arg (Arg1);
4420 Arg2 := Get_Pragma_Arg (Arg2);
4422 -- For Inherit case, ignore Invariant, process only Class case
4425 if not Class_Present (Ritem) then
4429 -- For Inherit false, process only item for right type
4432 if Entity (Arg1) /= Typ then
4438 Stmts := Empty_List;
4441 Exp := New_Copy_Tree (Arg2);
4444 -- We need to replace any occurrences of the name of the type
4445 -- with references to the object, converted to type'Class in
4446 -- the case of Invariant'Class aspects.
4448 Replace_Type_References (Exp, Chars (T));
4450 -- If this invariant comes from an aspect, find the aspect
4451 -- specification, and replace the saved expression because
4452 -- we need the subtype references replaced for the calls to
4453 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4454 -- and Check_Aspect_At_End_Of_Declarations.
4456 if From_Aspect_Specification (Ritem) then
4461 -- Loop to find corresponding aspect, note that this
4462 -- must be present given the pragma is marked delayed.
4464 Aitem := Next_Rep_Item (Ritem);
4465 while Present (Aitem) loop
4466 if Nkind (Aitem) = N_Aspect_Specification
4467 and then Aspect_Rep_Item (Aitem) = Ritem
4470 (Identifier (Aitem), New_Copy_Tree (Exp));
4474 Aitem := Next_Rep_Item (Aitem);
4479 -- Now we need to preanalyze the expression to properly capture
4480 -- the visibility in the visible part. The expression will not
4481 -- be analyzed for real until the body is analyzed, but that is
4482 -- at the end of the private part and has the wrong visibility.
4484 Set_Parent (Exp, N);
4485 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
4487 -- Build first two arguments for Check pragma
4490 Make_Pragma_Argument_Association (Loc,
4491 Expression => Make_Identifier (Loc, Name_Invariant)),
4492 Make_Pragma_Argument_Association (Loc, Expression => Exp));
4494 -- Add message if present in Invariant pragma
4496 if Present (Arg3) then
4497 Str := Strval (Get_Pragma_Arg (Arg3));
4499 -- If inherited case, and message starts "failed invariant",
4500 -- change it to be "failed inherited invariant".
4503 String_To_Name_Buffer (Str);
4505 if Name_Buffer (1 .. 16) = "failed invariant" then
4506 Insert_Str_In_Name_Buffer ("inherited ", 8);
4507 Str := String_From_Name_Buffer;
4512 Make_Pragma_Argument_Association (Loc,
4513 Expression => Make_String_Literal (Loc, Str)));
4516 -- Add Check pragma to list of statements
4520 Pragma_Identifier =>
4521 Make_Identifier (Loc, Name_Check),
4522 Pragma_Argument_Associations => Assoc));
4524 -- If Inherited case and option enabled, output info msg. Note
4525 -- that we know this is a case of Invariant'Class.
4527 if Inherit and Opt.List_Inherited_Aspects then
4528 Error_Msg_Sloc := Sloc (Ritem);
4530 ("?info: & inherits `Invariant''Class` aspect from #",
4536 Next_Rep_Item (Ritem);
4540 -- Start of processing for Build_Invariant_Procedure
4546 Set_Etype (Object_Entity, Typ);
4548 -- Add invariants for the current type
4550 Add_Invariants (Typ, Inherit => False);
4552 -- Add invariants for parent types
4555 Current_Typ : Entity_Id;
4556 Parent_Typ : Entity_Id;
4561 Parent_Typ := Etype (Current_Typ);
4563 if Is_Private_Type (Parent_Typ)
4564 and then Present (Full_View (Base_Type (Parent_Typ)))
4566 Parent_Typ := Full_View (Base_Type (Parent_Typ));
4569 exit when Parent_Typ = Current_Typ;
4571 Current_Typ := Parent_Typ;
4572 Add_Invariants (Current_Typ, Inherit => True);
4576 -- Build the procedure if we generated at least one Check pragma
4578 if Stmts /= No_List then
4580 -- Build procedure declaration
4583 Make_Defining_Identifier (Loc,
4584 Chars => New_External_Name (Chars (Typ), "Invariant"));
4585 Set_Has_Invariants (SId);
4586 Set_Invariant_Procedure (Typ, SId);
4589 Make_Procedure_Specification (Loc,
4590 Defining_Unit_Name => SId,
4591 Parameter_Specifications => New_List (
4592 Make_Parameter_Specification (Loc,
4593 Defining_Identifier => Object_Entity,
4594 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4596 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4598 -- Build procedure body
4601 Make_Defining_Identifier (Loc,
4602 Chars => New_External_Name (Chars (Typ), "Invariant"));
4605 Make_Procedure_Specification (Loc,
4606 Defining_Unit_Name => SId,
4607 Parameter_Specifications => New_List (
4608 Make_Parameter_Specification (Loc,
4609 Defining_Identifier =>
4610 Make_Defining_Identifier (Loc, Object_Name),
4611 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4614 Make_Subprogram_Body (Loc,
4615 Specification => Spec,
4616 Declarations => Empty_List,
4617 Handled_Statement_Sequence =>
4618 Make_Handled_Sequence_Of_Statements (Loc,
4619 Statements => Stmts));
4621 -- Insert procedure declaration and spec at the appropriate points.
4622 -- Skip this if there are no private declarations (that's an error
4623 -- that will be diagnosed elsewhere, and there is no point in having
4624 -- an invariant procedure set if the full declaration is missing).
4626 if Present (Private_Decls) then
4628 -- The spec goes at the end of visible declarations, but they have
4629 -- already been analyzed, so we need to explicitly do the analyze.
4631 Append_To (Visible_Decls, PDecl);
4634 -- The body goes at the end of the private declarations, which we
4635 -- have not analyzed yet, so we do not need to perform an explicit
4636 -- analyze call. We skip this if there are no private declarations
4637 -- (this is an error that will be caught elsewhere);
4639 Append_To (Private_Decls, PBody);
4642 end Build_Invariant_Procedure;
4644 ------------------------------
4645 -- Build_Predicate_Function --
4646 ------------------------------
4648 -- The procedure that is constructed here has the form
4650 -- function typPredicate (Ixxx : typ) return Boolean is
4653 -- exp1 and then exp2 and then ...
4654 -- and then typ1Predicate (typ1 (Ixxx))
4655 -- and then typ2Predicate (typ2 (Ixxx))
4657 -- end typPredicate;
4659 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4660 -- this is the point at which these expressions get analyzed, providing the
4661 -- required delay, and typ1, typ2, are entities from which predicates are
4662 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4663 -- use this function even if checks are off, e.g. for membership tests.
4665 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4666 Loc : constant Source_Ptr := Sloc (Typ);
4673 -- This is the expression for the return statement in the function. It
4674 -- is build by connecting the component predicates with AND THEN.
4676 procedure Add_Call (T : Entity_Id);
4677 -- Includes a call to the predicate function for type T in Expr if T
4678 -- has predicates and Predicate_Function (T) is non-empty.
4680 procedure Add_Predicates;
4681 -- Appends expressions for any Predicate pragmas in the rep item chain
4682 -- Typ to Expr. Note that we look only at items for this exact entity.
4683 -- Inheritance of predicates for the parent type is done by calling the
4684 -- Predicate_Function of the parent type, using Add_Call above.
4686 Object_Name : constant Name_Id := New_Internal_Name ('I');
4687 -- Name for argument of Predicate procedure
4689 Object_Entity : constant Entity_Id :=
4690 Make_Defining_Identifier (Loc, Object_Name);
4691 -- The entity for the spec entity for the argument
4693 Dynamic_Predicate_Present : Boolean := False;
4694 -- Set True if a dynamic predicate is present, results in the entire
4695 -- predicate being considered dynamic even if it looks static
4697 Static_Predicate_Present : Node_Id := Empty;
4698 -- Set to N_Pragma node for a static predicate if one is encountered.
4704 procedure Add_Call (T : Entity_Id) is
4708 if Present (T) and then Present (Predicate_Function (T)) then
4709 Set_Has_Predicates (Typ);
4711 -- Build the call to the predicate function of T
4715 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4717 -- Add call to evolving expression, using AND THEN if needed
4724 Left_Opnd => Relocate_Node (Expr),
4728 -- Output info message on inheritance if required. Note we do not
4729 -- give this information for generic actual types, since it is
4730 -- unwelcome noise in that case in instantiations. We also
4731 -- generally suppress the message in instantiations, and also
4732 -- if it involves internal names.
4734 if Opt.List_Inherited_Aspects
4735 and then not Is_Generic_Actual_Type (Typ)
4736 and then Instantiation_Depth (Sloc (Typ)) = 0
4737 and then not Is_Internal_Name (Chars (T))
4738 and then not Is_Internal_Name (Chars (Typ))
4740 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4741 Error_Msg_Node_2 := T;
4742 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4747 --------------------
4748 -- Add_Predicates --
4749 --------------------
4751 procedure Add_Predicates is
4756 procedure Replace_Type_Reference (N : Node_Id);
4757 -- Replace a single occurrence N of the subtype name with a reference
4758 -- to the formal of the predicate function. N can be an identifier
4759 -- referencing the subtype, or a selected component, representing an
4760 -- appropriately qualified occurrence of the subtype name.
4762 procedure Replace_Type_References is
4763 new Replace_Type_References_Generic (Replace_Type_Reference);
4764 -- Traverse an expression changing every occurrence of an identifier
4765 -- whose name matches the name of the subtype with a reference to
4766 -- the formal parameter of the predicate function.
4768 ----------------------------
4769 -- Replace_Type_Reference --
4770 ----------------------------
4772 procedure Replace_Type_Reference (N : Node_Id) is
4774 Rewrite (N, Make_Identifier (Loc, Object_Name));
4775 Set_Entity (N, Object_Entity);
4777 end Replace_Type_Reference;
4779 -- Start of processing for Add_Predicates
4782 Ritem := First_Rep_Item (Typ);
4783 while Present (Ritem) loop
4784 if Nkind (Ritem) = N_Pragma
4785 and then Pragma_Name (Ritem) = Name_Predicate
4787 if Present (Corresponding_Aspect (Ritem)) then
4788 case Chars (Identifier (Corresponding_Aspect (Ritem))) is
4789 when Name_Dynamic_Predicate =>
4790 Dynamic_Predicate_Present := True;
4791 when Name_Static_Predicate =>
4792 Static_Predicate_Present := Ritem;
4798 -- Acquire arguments
4800 Arg1 := First (Pragma_Argument_Associations (Ritem));
4801 Arg2 := Next (Arg1);
4803 Arg1 := Get_Pragma_Arg (Arg1);
4804 Arg2 := Get_Pragma_Arg (Arg2);
4806 -- See if this predicate pragma is for the current type or for
4807 -- its full view. A predicate on a private completion is placed
4808 -- on the partial view beause this is the visible entity that
4811 if Entity (Arg1) = Typ
4812 or else Full_View (Entity (Arg1)) = Typ
4815 -- We have a match, this entry is for our subtype
4817 -- We need to replace any occurrences of the name of the
4818 -- type with references to the object.
4820 Replace_Type_References (Arg2, Chars (Typ));
4822 -- If this predicate comes from an aspect, find the aspect
4823 -- specification, and replace the saved expression because
4824 -- we need the subtype references replaced for the calls to
4825 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4826 -- and Check_Aspect_At_End_Of_Declarations.
4828 if From_Aspect_Specification (Ritem) then
4833 -- Loop to find corresponding aspect, note that this
4834 -- must be present given the pragma is marked delayed.
4836 Aitem := Next_Rep_Item (Ritem);
4838 if Nkind (Aitem) = N_Aspect_Specification
4839 and then Aspect_Rep_Item (Aitem) = Ritem
4842 (Identifier (Aitem), New_Copy_Tree (Arg2));
4846 Aitem := Next_Rep_Item (Aitem);
4851 -- Now we can add the expression
4854 Expr := Relocate_Node (Arg2);
4856 -- There already was a predicate, so add to it
4861 Left_Opnd => Relocate_Node (Expr),
4862 Right_Opnd => Relocate_Node (Arg2));
4867 Next_Rep_Item (Ritem);
4871 -- Start of processing for Build_Predicate_Function
4874 -- Initialize for construction of statement list
4878 -- Return if already built or if type does not have predicates
4880 if not Has_Predicates (Typ)
4881 or else Present (Predicate_Function (Typ))
4886 -- Add Predicates for the current type
4890 -- Add predicates for ancestor if present
4893 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4895 if Present (Atyp) then
4900 -- If we have predicates, build the function
4902 if Present (Expr) then
4904 -- Build function declaration
4906 pragma Assert (Has_Predicates (Typ));
4908 Make_Defining_Identifier (Loc,
4909 Chars => New_External_Name (Chars (Typ), "Predicate"));
4910 Set_Has_Predicates (SId);
4911 Set_Predicate_Function (Typ, SId);
4914 Make_Function_Specification (Loc,
4915 Defining_Unit_Name => SId,
4916 Parameter_Specifications => New_List (
4917 Make_Parameter_Specification (Loc,
4918 Defining_Identifier => Object_Entity,
4919 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4920 Result_Definition =>
4921 New_Occurrence_Of (Standard_Boolean, Loc));
4923 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4925 -- Build function body
4928 Make_Defining_Identifier (Loc,
4929 Chars => New_External_Name (Chars (Typ), "Predicate"));
4932 Make_Function_Specification (Loc,
4933 Defining_Unit_Name => SId,
4934 Parameter_Specifications => New_List (
4935 Make_Parameter_Specification (Loc,
4936 Defining_Identifier =>
4937 Make_Defining_Identifier (Loc, Object_Name),
4939 New_Occurrence_Of (Typ, Loc))),
4940 Result_Definition =>
4941 New_Occurrence_Of (Standard_Boolean, Loc));
4944 Make_Subprogram_Body (Loc,
4945 Specification => Spec,
4946 Declarations => Empty_List,
4947 Handled_Statement_Sequence =>
4948 Make_Handled_Sequence_Of_Statements (Loc,
4949 Statements => New_List (
4950 Make_Simple_Return_Statement (Loc,
4951 Expression => Expr))));
4953 -- Insert declaration before freeze node and body after
4955 Insert_Before_And_Analyze (N, FDecl);
4956 Insert_After_And_Analyze (N, FBody);
4958 -- Deal with static predicate case
4960 if Ekind_In (Typ, E_Enumeration_Subtype,
4961 E_Modular_Integer_Subtype,
4962 E_Signed_Integer_Subtype)
4963 and then Is_Static_Subtype (Typ)
4964 and then not Dynamic_Predicate_Present
4966 Build_Static_Predicate (Typ, Expr, Object_Name);
4968 if Present (Static_Predicate_Present)
4969 and No (Static_Predicate (Typ))
4972 ("expression does not have required form for "
4973 & "static predicate",
4974 Next (First (Pragma_Argument_Associations
4975 (Static_Predicate_Present))));
4979 end Build_Predicate_Function;
4981 ----------------------------
4982 -- Build_Static_Predicate --
4983 ----------------------------
4985 procedure Build_Static_Predicate
4990 Loc : constant Source_Ptr := Sloc (Expr);
4992 Non_Static : exception;
4993 -- Raised if something non-static is found
4995 Btyp : constant Entity_Id := Base_Type (Typ);
4997 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4998 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4999 -- Low bound and high bound value of base type of Typ
5001 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
5002 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
5003 -- Low bound and high bound values of static subtype Typ
5008 -- One entry in a Rlist value, a single REnt (range entry) value
5009 -- denotes one range from Lo to Hi. To represent a single value
5010 -- range Lo = Hi = value.
5012 type RList is array (Nat range <>) of REnt;
5013 -- A list of ranges. The ranges are sorted in increasing order,
5014 -- and are disjoint (there is a gap of at least one value between
5015 -- each range in the table). A value is in the set of ranges in
5016 -- Rlist if it lies within one of these ranges
5018 False_Range : constant RList :=
5019 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
5020 -- An empty set of ranges represents a range list that can never be
5021 -- satisfied, since there are no ranges in which the value could lie,
5022 -- so it does not lie in any of them. False_Range is a canonical value
5023 -- for this empty set, but general processing should test for an Rlist
5024 -- with length zero (see Is_False predicate), since other null ranges
5025 -- may appear which must be treated as False.
5027 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
5028 -- Range representing True, value must be in the base range
5030 function "and" (Left, Right : RList) return RList;
5031 -- And's together two range lists, returning a range list. This is
5032 -- a set intersection operation.
5034 function "or" (Left, Right : RList) return RList;
5035 -- Or's together two range lists, returning a range list. This is a
5036 -- set union operation.
5038 function "not" (Right : RList) return RList;
5039 -- Returns complement of a given range list, i.e. a range list
5040 -- representing all the values in TLo .. THi that are not in the
5041 -- input operand Right.
5043 function Build_Val (V : Uint) return Node_Id;
5044 -- Return an analyzed N_Identifier node referencing this value, suitable
5045 -- for use as an entry in the Static_Predicate list. This node is typed
5046 -- with the base type.
5048 function Build_Range (Lo, Hi : Uint) return Node_Id;
5049 -- Return an analyzed N_Range node referencing this range, suitable
5050 -- for use as an entry in the Static_Predicate list. This node is typed
5051 -- with the base type.
5053 function Get_RList (Exp : Node_Id) return RList;
5054 -- This is a recursive routine that converts the given expression into
5055 -- a list of ranges, suitable for use in building the static predicate.
5057 function Is_False (R : RList) return Boolean;
5058 pragma Inline (Is_False);
5059 -- Returns True if the given range list is empty, and thus represents
5060 -- a False list of ranges that can never be satisfied.
5062 function Is_True (R : RList) return Boolean;
5063 -- Returns True if R trivially represents the True predicate by having
5064 -- a single range from BLo to BHi.
5066 function Is_Type_Ref (N : Node_Id) return Boolean;
5067 pragma Inline (Is_Type_Ref);
5068 -- Returns if True if N is a reference to the type for the predicate in
5069 -- the expression (i.e. if it is an identifier whose Chars field matches
5070 -- the Nam given in the call).
5072 function Lo_Val (N : Node_Id) return Uint;
5073 -- Given static expression or static range from a Static_Predicate list,
5074 -- gets expression value or low bound of range.
5076 function Hi_Val (N : Node_Id) return Uint;
5077 -- Given static expression or static range from a Static_Predicate list,
5078 -- gets expression value of high bound of range.
5080 function Membership_Entry (N : Node_Id) return RList;
5081 -- Given a single membership entry (range, value, or subtype), returns
5082 -- the corresponding range list. Raises Static_Error if not static.
5084 function Membership_Entries (N : Node_Id) return RList;
5085 -- Given an element on an alternatives list of a membership operation,
5086 -- returns the range list corresponding to this entry and all following
5087 -- entries (i.e. returns the "or" of this list of values).
5089 function Stat_Pred (Typ : Entity_Id) return RList;
5090 -- Given a type, if it has a static predicate, then return the predicate
5091 -- as a range list, otherwise raise Non_Static.
5097 function "and" (Left, Right : RList) return RList is
5099 -- First range of result
5101 SLeft : Nat := Left'First;
5102 -- Start of rest of left entries
5104 SRight : Nat := Right'First;
5105 -- Start of rest of right entries
5108 -- If either range is True, return the other
5110 if Is_True (Left) then
5112 elsif Is_True (Right) then
5116 -- If either range is False, return False
5118 if Is_False (Left) or else Is_False (Right) then
5122 -- Loop to remove entries at start that are disjoint, and thus
5123 -- just get discarded from the result entirely.
5126 -- If no operands left in either operand, result is false
5128 if SLeft > Left'Last or else SRight > Right'Last then
5131 -- Discard first left operand entry if disjoint with right
5133 elsif Left (SLeft).Hi < Right (SRight).Lo then
5136 -- Discard first right operand entry if disjoint with left
5138 elsif Right (SRight).Hi < Left (SLeft).Lo then
5139 SRight := SRight + 1;
5141 -- Otherwise we have an overlapping entry
5148 -- Now we have two non-null operands, and first entries overlap.
5149 -- The first entry in the result will be the overlapping part of
5150 -- these two entries.
5152 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
5153 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
5155 -- Now we can remove the entry that ended at a lower value, since
5156 -- its contribution is entirely contained in Fent.
5158 if Left (SLeft).Hi <= Right (SRight).Hi then
5161 SRight := SRight + 1;
5164 -- Compute result by concatenating this first entry with the "and"
5165 -- of the remaining parts of the left and right operands. Note that
5166 -- if either of these is empty, "and" will yield empty, so that we
5167 -- will end up with just Fent, which is what we want in that case.
5170 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
5177 function "not" (Right : RList) return RList is
5179 -- Return True if False range
5181 if Is_False (Right) then
5185 -- Return False if True range
5187 if Is_True (Right) then
5191 -- Here if not trivial case
5194 Result : RList (1 .. Right'Length + 1);
5195 -- May need one more entry for gap at beginning and end
5198 -- Number of entries stored in Result
5203 if Right (Right'First).Lo > TLo then
5205 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
5208 -- Gaps between ranges
5210 for J in Right'First .. Right'Last - 1 loop
5213 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
5218 if Right (Right'Last).Hi < THi then
5220 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
5223 return Result (1 .. Count);
5231 function "or" (Left, Right : RList) return RList is
5233 -- First range of result
5235 SLeft : Nat := Left'First;
5236 -- Start of rest of left entries
5238 SRight : Nat := Right'First;
5239 -- Start of rest of right entries
5242 -- If either range is True, return True
5244 if Is_True (Left) or else Is_True (Right) then
5248 -- If either range is False (empty), return the other
5250 if Is_False (Left) then
5252 elsif Is_False (Right) then
5256 -- Initialize result first entry from left or right operand
5257 -- depending on which starts with the lower range.
5259 if Left (SLeft).Lo < Right (SRight).Lo then
5260 FEnt := Left (SLeft);
5263 FEnt := Right (SRight);
5264 SRight := SRight + 1;
5267 -- This loop eats ranges from left and right operands that
5268 -- are contiguous with the first range we are gathering.
5271 -- Eat first entry in left operand if contiguous or
5272 -- overlapped by gathered first operand of result.
5274 if SLeft <= Left'Last
5275 and then Left (SLeft).Lo <= FEnt.Hi + 1
5277 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
5280 -- Eat first entry in right operand if contiguous or
5281 -- overlapped by gathered right operand of result.
5283 elsif SRight <= Right'Last
5284 and then Right (SRight).Lo <= FEnt.Hi + 1
5286 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
5287 SRight := SRight + 1;
5289 -- All done if no more entries to eat!
5296 -- Obtain result as the first entry we just computed, concatenated
5297 -- to the "or" of the remaining results (if one operand is empty,
5298 -- this will just concatenate with the other
5301 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
5308 function Build_Range (Lo, Hi : Uint) return Node_Id is
5312 return Build_Val (Hi);
5316 Low_Bound => Build_Val (Lo),
5317 High_Bound => Build_Val (Hi));
5318 Set_Etype (Result, Btyp);
5319 Set_Analyzed (Result);
5328 function Build_Val (V : Uint) return Node_Id is
5332 if Is_Enumeration_Type (Typ) then
5333 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
5335 Result := Make_Integer_Literal (Loc, V);
5338 Set_Etype (Result, Btyp);
5339 Set_Is_Static_Expression (Result);
5340 Set_Analyzed (Result);
5348 function Get_RList (Exp : Node_Id) return RList is
5353 -- Static expression can only be true or false
5355 if Is_OK_Static_Expression (Exp) then
5359 if Expr_Value (Exp) = 0 then
5366 -- Otherwise test node type
5374 when N_Op_And | N_And_Then =>
5375 return Get_RList (Left_Opnd (Exp))
5377 Get_RList (Right_Opnd (Exp));
5381 when N_Op_Or | N_Or_Else =>
5382 return Get_RList (Left_Opnd (Exp))
5384 Get_RList (Right_Opnd (Exp));
5389 return not Get_RList (Right_Opnd (Exp));
5391 -- Comparisons of type with static value
5393 when N_Op_Compare =>
5394 -- Type is left operand
5396 if Is_Type_Ref (Left_Opnd (Exp))
5397 and then Is_OK_Static_Expression (Right_Opnd (Exp))
5399 Val := Expr_Value (Right_Opnd (Exp));
5401 -- Typ is right operand
5403 elsif Is_Type_Ref (Right_Opnd (Exp))
5404 and then Is_OK_Static_Expression (Left_Opnd (Exp))
5406 Val := Expr_Value (Left_Opnd (Exp));
5408 -- Invert sense of comparison
5411 when N_Op_Gt => Op := N_Op_Lt;
5412 when N_Op_Lt => Op := N_Op_Gt;
5413 when N_Op_Ge => Op := N_Op_Le;
5414 when N_Op_Le => Op := N_Op_Ge;
5415 when others => null;
5418 -- Other cases are non-static
5424 -- Construct range according to comparison operation
5428 return RList'(1 => REnt'(Val, Val));
5431 return RList'(1 => REnt'(Val, BHi));
5434 return RList'(1 => REnt'(Val + 1, BHi));
5437 return RList'(1 => REnt'(BLo, Val));
5440 return RList'(1 => REnt'(BLo, Val - 1));
5443 return RList'(REnt'(BLo, Val - 1),
5444 REnt'(Val + 1, BHi));
5447 raise Program_Error;
5453 if not Is_Type_Ref (Left_Opnd (Exp)) then
5457 if Present (Right_Opnd (Exp)) then
5458 return Membership_Entry (Right_Opnd (Exp));
5460 return Membership_Entries (First (Alternatives (Exp)));
5463 -- Negative membership (NOT IN)
5466 if not Is_Type_Ref (Left_Opnd (Exp)) then
5470 if Present (Right_Opnd (Exp)) then
5471 return not Membership_Entry (Right_Opnd (Exp));
5473 return not Membership_Entries (First (Alternatives (Exp)));
5476 -- Function call, may be call to static predicate
5478 when N_Function_Call =>
5479 if Is_Entity_Name (Name (Exp)) then
5481 Ent : constant Entity_Id := Entity (Name (Exp));
5483 if Has_Predicates (Ent) then
5484 return Stat_Pred (Etype (First_Formal (Ent)));
5489 -- Other function call cases are non-static
5493 -- Qualified expression, dig out the expression
5495 when N_Qualified_Expression =>
5496 return Get_RList (Expression (Exp));
5501 return (Get_RList (Left_Opnd (Exp))
5502 and not Get_RList (Right_Opnd (Exp)))
5503 or (Get_RList (Right_Opnd (Exp))
5504 and not Get_RList (Left_Opnd (Exp)));
5506 -- Any other node type is non-static
5517 function Hi_Val (N : Node_Id) return Uint is
5519 if Is_Static_Expression (N) then
5520 return Expr_Value (N);
5522 pragma Assert (Nkind (N) = N_Range);
5523 return Expr_Value (High_Bound (N));
5531 function Is_False (R : RList) return Boolean is
5533 return R'Length = 0;
5540 function Is_True (R : RList) return Boolean is
5543 and then R (R'First).Lo = BLo
5544 and then R (R'First).Hi = BHi;
5551 function Is_Type_Ref (N : Node_Id) return Boolean is
5553 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
5560 function Lo_Val (N : Node_Id) return Uint is
5562 if Is_Static_Expression (N) then
5563 return Expr_Value (N);
5565 pragma Assert (Nkind (N) = N_Range);
5566 return Expr_Value (Low_Bound (N));
5570 ------------------------
5571 -- Membership_Entries --
5572 ------------------------
5574 function Membership_Entries (N : Node_Id) return RList is
5576 if No (Next (N)) then
5577 return Membership_Entry (N);
5579 return Membership_Entry (N) or Membership_Entries (Next (N));
5581 end Membership_Entries;
5583 ----------------------
5584 -- Membership_Entry --
5585 ----------------------
5587 function Membership_Entry (N : Node_Id) return RList is
5595 if Nkind (N) = N_Range then
5596 if not Is_Static_Expression (Low_Bound (N))
5598 not Is_Static_Expression (High_Bound (N))
5602 SLo := Expr_Value (Low_Bound (N));
5603 SHi := Expr_Value (High_Bound (N));
5604 return RList'(1 => REnt'(SLo, SHi));
5607 -- Static expression case
5609 elsif Is_Static_Expression (N) then
5610 Val := Expr_Value (N);
5611 return RList'(1 => REnt'(Val, Val));
5613 -- Identifier (other than static expression) case
5615 else pragma Assert (Nkind (N) = N_Identifier);
5619 if Is_Type (Entity (N)) then
5621 -- If type has predicates, process them
5623 if Has_Predicates (Entity (N)) then
5624 return Stat_Pred (Entity (N));
5626 -- For static subtype without predicates, get range
5628 elsif Is_Static_Subtype (Entity (N)) then
5629 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
5630 SHi := Expr_Value (Type_High_Bound (Entity (N)));
5631 return RList'(1 => REnt'(SLo, SHi));
5633 -- Any other type makes us non-static
5639 -- Any other kind of identifier in predicate (e.g. a non-static
5640 -- expression value) means this is not a static predicate.
5646 end Membership_Entry;
5652 function Stat_Pred (Typ : Entity_Id) return RList is
5654 -- Not static if type does not have static predicates
5656 if not Has_Predicates (Typ)
5657 or else No (Static_Predicate (Typ))
5662 -- Otherwise we convert the predicate list to a range list
5665 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5669 P := First (Static_Predicate (Typ));
5670 for J in Result'Range loop
5671 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5679 -- Start of processing for Build_Static_Predicate
5682 -- Now analyze the expression to see if it is a static predicate
5685 Ranges : constant RList := Get_RList (Expr);
5686 -- Range list from expression if it is static
5691 -- Convert range list into a form for the static predicate. In the
5692 -- Ranges array, we just have raw ranges, these must be converted
5693 -- to properly typed and analyzed static expressions or range nodes.
5695 -- Note: here we limit ranges to the ranges of the subtype, so that
5696 -- a predicate is always false for values outside the subtype. That
5697 -- seems fine, such values are invalid anyway, and considering them
5698 -- to fail the predicate seems allowed and friendly, and furthermore
5699 -- simplifies processing for case statements and loops.
5703 for J in Ranges'Range loop
5705 Lo : Uint := Ranges (J).Lo;
5706 Hi : Uint := Ranges (J).Hi;
5709 -- Ignore completely out of range entry
5711 if Hi < TLo or else Lo > THi then
5714 -- Otherwise process entry
5717 -- Adjust out of range value to subtype range
5727 -- Convert range into required form
5730 Append_To (Plist, Build_Val (Lo));
5732 Append_To (Plist, Build_Range (Lo, Hi));
5738 -- Processing was successful and all entries were static, so now we
5739 -- can store the result as the predicate list.
5741 Set_Static_Predicate (Typ, Plist);
5743 -- The processing for static predicates put the expression into
5744 -- canonical form as a series of ranges. It also eliminated
5745 -- duplicates and collapsed and combined ranges. We might as well
5746 -- replace the alternatives list of the right operand of the
5747 -- membership test with the static predicate list, which will
5748 -- usually be more efficient.
5751 New_Alts : constant List_Id := New_List;
5756 Old_Node := First (Plist);
5757 while Present (Old_Node) loop
5758 New_Node := New_Copy (Old_Node);
5760 if Nkind (New_Node) = N_Range then
5761 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5762 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5765 Append_To (New_Alts, New_Node);
5769 -- If empty list, replace by False
5771 if Is_Empty_List (New_Alts) then
5772 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5774 -- Else replace by set membership test
5779 Left_Opnd => Make_Identifier (Loc, Nam),
5780 Right_Opnd => Empty,
5781 Alternatives => New_Alts));
5783 -- Resolve new expression in function context
5785 Install_Formals (Predicate_Function (Typ));
5786 Push_Scope (Predicate_Function (Typ));
5787 Analyze_And_Resolve (Expr, Standard_Boolean);
5793 -- If non-static, return doing nothing
5798 end Build_Static_Predicate;
5800 -----------------------------------------
5801 -- Check_Aspect_At_End_Of_Declarations --
5802 -----------------------------------------
5804 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5805 Ent : constant Entity_Id := Entity (ASN);
5806 Ident : constant Node_Id := Identifier (ASN);
5808 Freeze_Expr : constant Node_Id := Expression (ASN);
5809 -- Expression from call to Check_Aspect_At_Freeze_Point
5811 End_Decl_Expr : constant Node_Id := Entity (Ident);
5812 -- Expression to be analyzed at end of declarations
5814 T : constant Entity_Id := Etype (Freeze_Expr);
5815 -- Type required for preanalyze call
5817 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5820 -- Set False if error
5822 -- On entry to this procedure, Entity (Ident) contains a copy of the
5823 -- original expression from the aspect, saved for this purpose, and
5824 -- but Expression (Ident) is a preanalyzed copy of the expression,
5825 -- preanalyzed just after the freeze point.
5828 -- Case of stream attributes, just have to compare entities
5830 if A_Id = Aspect_Input or else
5831 A_Id = Aspect_Output or else
5832 A_Id = Aspect_Read or else
5835 Analyze (End_Decl_Expr);
5836 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5838 elsif A_Id = Aspect_Variable_Indexing or else
5839 A_Id = Aspect_Constant_Indexing or else
5840 A_Id = Aspect_Default_Iterator or else
5841 A_Id = Aspect_Iterator_Element
5843 -- Make type unfrozen before analysis, to prevent spurious errors
5844 -- about late attributes.
5846 Set_Is_Frozen (Ent, False);
5847 Analyze (End_Decl_Expr);
5848 Analyze (Aspect_Rep_Item (ASN));
5849 Set_Is_Frozen (Ent, True);
5851 -- If the end of declarations comes before any other freeze
5852 -- point, the Freeze_Expr is not analyzed: no check needed.
5855 Analyzed (Freeze_Expr)
5856 and then not In_Instance
5857 and then Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5862 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5863 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5866 -- Output error message if error
5870 ("visibility of aspect for& changes after freeze point",
5873 ("?info: & is frozen here, aspects evaluated at this point",
5874 Freeze_Node (Ent), Ent);
5876 end Check_Aspect_At_End_Of_Declarations;
5878 ----------------------------------
5879 -- Check_Aspect_At_Freeze_Point --
5880 ----------------------------------
5882 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5883 Ident : constant Node_Id := Identifier (ASN);
5884 -- Identifier (use Entity field to save expression)
5887 -- Type required for preanalyze call
5889 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5892 -- On entry to this procedure, Entity (Ident) contains a copy of the
5893 -- original expression from the aspect, saved for this purpose.
5895 -- On exit from this procedure Entity (Ident) is unchanged, still
5896 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5897 -- of the expression, preanalyzed just after the freeze point.
5899 -- Make a copy of the expression to be preanalyed
5901 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5903 -- Find type for preanalyze call
5907 -- No_Aspect should be impossible
5910 raise Program_Error;
5912 -- Library unit aspects should be impossible (never delayed)
5914 when Library_Unit_Aspects =>
5915 raise Program_Error;
5917 -- Aspects taking an optional boolean argument. Should be impossible
5918 -- since these are never delayed.
5920 when Boolean_Aspects =>
5921 raise Program_Error;
5923 -- Test_Case aspect applies to entries and subprograms, hence should
5924 -- never be delayed.
5926 when Aspect_Test_Case =>
5927 raise Program_Error;
5929 when Aspect_Attach_Handler =>
5930 T := RTE (RE_Interrupt_ID);
5932 -- Default_Value is resolved with the type entity in question
5934 when Aspect_Default_Value =>
5937 -- Default_Component_Value is resolved with the component type
5939 when Aspect_Default_Component_Value =>
5940 T := Component_Type (Entity (ASN));
5942 -- Aspects corresponding to attribute definition clauses
5944 when Aspect_Address =>
5945 T := RTE (RE_Address);
5947 when Aspect_Bit_Order =>
5948 T := RTE (RE_Bit_Order);
5951 T := RTE (RE_CPU_Range);
5953 when Aspect_Dispatching_Domain =>
5954 T := RTE (RE_Dispatching_Domain);
5956 when Aspect_External_Tag =>
5957 T := Standard_String;
5959 when Aspect_Priority | Aspect_Interrupt_Priority =>
5960 T := Standard_Integer;
5962 when Aspect_Small =>
5963 T := Universal_Real;
5965 when Aspect_Storage_Pool =>
5966 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5968 when Aspect_Alignment |
5969 Aspect_Component_Size |
5970 Aspect_Machine_Radix |
5971 Aspect_Object_Size |
5973 Aspect_Storage_Size |
5974 Aspect_Stream_Size |
5975 Aspect_Value_Size =>
5978 -- Stream attribute. Special case, the expression is just an entity
5979 -- that does not need any resolution, so just analyze.
5985 Analyze (Expression (ASN));
5988 -- Same for Iterator aspects, where the expression is a function
5989 -- name. Legality rules are checked separately.
5991 when Aspect_Constant_Indexing |
5992 Aspect_Default_Iterator |
5993 Aspect_Iterator_Element |
5994 Aspect_Implicit_Dereference |
5995 Aspect_Variable_Indexing =>
5996 Analyze (Expression (ASN));
5999 -- Suppress/Unsuppress/Warnings should never be delayed
6001 when Aspect_Suppress |
6004 raise Program_Error;
6006 -- Pre/Post/Invariant/Predicate take boolean expressions
6008 when Aspect_Dynamic_Predicate |
6011 Aspect_Precondition |
6013 Aspect_Postcondition |
6015 Aspect_Static_Predicate |
6016 Aspect_Type_Invariant =>
6017 T := Standard_Boolean;
6020 -- Do the preanalyze call
6022 Preanalyze_Spec_Expression (Expression (ASN), T);
6023 end Check_Aspect_At_Freeze_Point;
6025 -----------------------------------
6026 -- Check_Constant_Address_Clause --
6027 -----------------------------------
6029 procedure Check_Constant_Address_Clause
6033 procedure Check_At_Constant_Address (Nod : Node_Id);
6034 -- Checks that the given node N represents a name whose 'Address is
6035 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
6036 -- address value is the same at the point of declaration of U_Ent and at
6037 -- the time of elaboration of the address clause.
6039 procedure Check_Expr_Constants (Nod : Node_Id);
6040 -- Checks that Nod meets the requirements for a constant address clause
6041 -- in the sense of the enclosing procedure.
6043 procedure Check_List_Constants (Lst : List_Id);
6044 -- Check that all elements of list Lst meet the requirements for a
6045 -- constant address clause in the sense of the enclosing procedure.
6047 -------------------------------
6048 -- Check_At_Constant_Address --
6049 -------------------------------
6051 procedure Check_At_Constant_Address (Nod : Node_Id) is
6053 if Is_Entity_Name (Nod) then
6054 if Present (Address_Clause (Entity ((Nod)))) then
6056 ("invalid address clause for initialized object &!",
6059 ("address for& cannot" &
6060 " depend on another address clause! (RM 13.1(22))!",
6063 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
6064 and then Sloc (U_Ent) < Sloc (Entity (Nod))
6067 ("invalid address clause for initialized object &!",
6069 Error_Msg_Node_2 := U_Ent;
6071 ("\& must be defined before & (RM 13.1(22))!",
6075 elsif Nkind (Nod) = N_Selected_Component then
6077 T : constant Entity_Id := Etype (Prefix (Nod));
6080 if (Is_Record_Type (T)
6081 and then Has_Discriminants (T))
6084 and then Is_Record_Type (Designated_Type (T))
6085 and then Has_Discriminants (Designated_Type (T)))
6088 ("invalid address clause for initialized object &!",
6091 ("\address cannot depend on component" &
6092 " of discriminated record (RM 13.1(22))!",
6095 Check_At_Constant_Address (Prefix (Nod));
6099 elsif Nkind (Nod) = N_Indexed_Component then
6100 Check_At_Constant_Address (Prefix (Nod));
6101 Check_List_Constants (Expressions (Nod));
6104 Check_Expr_Constants (Nod);
6106 end Check_At_Constant_Address;
6108 --------------------------
6109 -- Check_Expr_Constants --
6110 --------------------------
6112 procedure Check_Expr_Constants (Nod : Node_Id) is
6113 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
6114 Ent : Entity_Id := Empty;
6117 if Nkind (Nod) in N_Has_Etype
6118 and then Etype (Nod) = Any_Type
6124 when N_Empty | N_Error =>
6127 when N_Identifier | N_Expanded_Name =>
6128 Ent := Entity (Nod);
6130 -- We need to look at the original node if it is different
6131 -- from the node, since we may have rewritten things and
6132 -- substituted an identifier representing the rewrite.
6134 if Original_Node (Nod) /= Nod then
6135 Check_Expr_Constants (Original_Node (Nod));
6137 -- If the node is an object declaration without initial
6138 -- value, some code has been expanded, and the expression
6139 -- is not constant, even if the constituents might be
6140 -- acceptable, as in A'Address + offset.
6142 if Ekind (Ent) = E_Variable
6144 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
6146 No (Expression (Declaration_Node (Ent)))
6149 ("invalid address clause for initialized object &!",
6152 -- If entity is constant, it may be the result of expanding
6153 -- a check. We must verify that its declaration appears
6154 -- before the object in question, else we also reject the
6157 elsif Ekind (Ent) = E_Constant
6158 and then In_Same_Source_Unit (Ent, U_Ent)
6159 and then Sloc (Ent) > Loc_U_Ent
6162 ("invalid address clause for initialized object &!",
6169 -- Otherwise look at the identifier and see if it is OK
6171 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
6172 or else Is_Type (Ent)
6177 Ekind (Ent) = E_Constant
6179 Ekind (Ent) = E_In_Parameter
6181 -- This is the case where we must have Ent defined before
6182 -- U_Ent. Clearly if they are in different units this
6183 -- requirement is met since the unit containing Ent is
6184 -- already processed.
6186 if not In_Same_Source_Unit (Ent, U_Ent) then
6189 -- Otherwise location of Ent must be before the location
6190 -- of U_Ent, that's what prior defined means.
6192 elsif Sloc (Ent) < Loc_U_Ent then
6197 ("invalid address clause for initialized object &!",
6199 Error_Msg_Node_2 := U_Ent;
6201 ("\& must be defined before & (RM 13.1(22))!",
6205 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
6206 Check_Expr_Constants (Original_Node (Nod));
6210 ("invalid address clause for initialized object &!",
6213 if Comes_From_Source (Ent) then
6215 ("\reference to variable& not allowed"
6216 & " (RM 13.1(22))!", Nod, Ent);
6219 ("non-static expression not allowed"
6220 & " (RM 13.1(22))!", Nod);
6224 when N_Integer_Literal =>
6226 -- If this is a rewritten unchecked conversion, in a system
6227 -- where Address is an integer type, always use the base type
6228 -- for a literal value. This is user-friendly and prevents
6229 -- order-of-elaboration issues with instances of unchecked
6232 if Nkind (Original_Node (Nod)) = N_Function_Call then
6233 Set_Etype (Nod, Base_Type (Etype (Nod)));
6236 when N_Real_Literal |
6238 N_Character_Literal =>
6242 Check_Expr_Constants (Low_Bound (Nod));
6243 Check_Expr_Constants (High_Bound (Nod));
6245 when N_Explicit_Dereference =>
6246 Check_Expr_Constants (Prefix (Nod));
6248 when N_Indexed_Component =>
6249 Check_Expr_Constants (Prefix (Nod));
6250 Check_List_Constants (Expressions (Nod));
6253 Check_Expr_Constants (Prefix (Nod));
6254 Check_Expr_Constants (Discrete_Range (Nod));
6256 when N_Selected_Component =>
6257 Check_Expr_Constants (Prefix (Nod));
6259 when N_Attribute_Reference =>
6260 if Attribute_Name (Nod) = Name_Address
6262 Attribute_Name (Nod) = Name_Access
6264 Attribute_Name (Nod) = Name_Unchecked_Access
6266 Attribute_Name (Nod) = Name_Unrestricted_Access
6268 Check_At_Constant_Address (Prefix (Nod));
6271 Check_Expr_Constants (Prefix (Nod));
6272 Check_List_Constants (Expressions (Nod));
6276 Check_List_Constants (Component_Associations (Nod));
6277 Check_List_Constants (Expressions (Nod));
6279 when N_Component_Association =>
6280 Check_Expr_Constants (Expression (Nod));
6282 when N_Extension_Aggregate =>
6283 Check_Expr_Constants (Ancestor_Part (Nod));
6284 Check_List_Constants (Component_Associations (Nod));
6285 Check_List_Constants (Expressions (Nod));
6290 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
6291 Check_Expr_Constants (Left_Opnd (Nod));
6292 Check_Expr_Constants (Right_Opnd (Nod));
6295 Check_Expr_Constants (Right_Opnd (Nod));
6297 when N_Type_Conversion |
6298 N_Qualified_Expression |
6300 Check_Expr_Constants (Expression (Nod));
6302 when N_Unchecked_Type_Conversion =>
6303 Check_Expr_Constants (Expression (Nod));
6305 -- If this is a rewritten unchecked conversion, subtypes in
6306 -- this node are those created within the instance. To avoid
6307 -- order of elaboration issues, replace them with their base
6308 -- types. Note that address clauses can cause order of
6309 -- elaboration problems because they are elaborated by the
6310 -- back-end at the point of definition, and may mention
6311 -- entities declared in between (as long as everything is
6312 -- static). It is user-friendly to allow unchecked conversions
6315 if Nkind (Original_Node (Nod)) = N_Function_Call then
6316 Set_Etype (Expression (Nod),
6317 Base_Type (Etype (Expression (Nod))));
6318 Set_Etype (Nod, Base_Type (Etype (Nod)));
6321 when N_Function_Call =>
6322 if not Is_Pure (Entity (Name (Nod))) then
6324 ("invalid address clause for initialized object &!",
6328 ("\function & is not pure (RM 13.1(22))!",
6329 Nod, Entity (Name (Nod)));
6332 Check_List_Constants (Parameter_Associations (Nod));
6335 when N_Parameter_Association =>
6336 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
6340 ("invalid address clause for initialized object &!",
6343 ("\must be constant defined before& (RM 13.1(22))!",
6346 end Check_Expr_Constants;
6348 --------------------------
6349 -- Check_List_Constants --
6350 --------------------------
6352 procedure Check_List_Constants (Lst : List_Id) is
6356 if Present (Lst) then
6357 Nod1 := First (Lst);
6358 while Present (Nod1) loop
6359 Check_Expr_Constants (Nod1);
6363 end Check_List_Constants;
6365 -- Start of processing for Check_Constant_Address_Clause
6368 -- If rep_clauses are to be ignored, no need for legality checks. In
6369 -- particular, no need to pester user about rep clauses that violate
6370 -- the rule on constant addresses, given that these clauses will be
6371 -- removed by Freeze before they reach the back end.
6373 if not Ignore_Rep_Clauses then
6374 Check_Expr_Constants (Expr);
6376 end Check_Constant_Address_Clause;
6378 ----------------------------------------
6379 -- Check_Record_Representation_Clause --
6380 ----------------------------------------
6382 procedure Check_Record_Representation_Clause (N : Node_Id) is
6383 Loc : constant Source_Ptr := Sloc (N);
6384 Ident : constant Node_Id := Identifier (N);
6385 Rectype : Entity_Id;
6390 Hbit : Uint := Uint_0;
6394 Max_Bit_So_Far : Uint;
6395 -- Records the maximum bit position so far. If all field positions
6396 -- are monotonically increasing, then we can skip the circuit for
6397 -- checking for overlap, since no overlap is possible.
6399 Tagged_Parent : Entity_Id := Empty;
6400 -- This is set in the case of a derived tagged type for which we have
6401 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
6402 -- positioned by record representation clauses). In this case we must
6403 -- check for overlap between components of this tagged type, and the
6404 -- components of its parent. Tagged_Parent will point to this parent
6405 -- type. For all other cases Tagged_Parent is left set to Empty.
6407 Parent_Last_Bit : Uint;
6408 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
6409 -- last bit position for any field in the parent type. We only need to
6410 -- check overlap for fields starting below this point.
6412 Overlap_Check_Required : Boolean;
6413 -- Used to keep track of whether or not an overlap check is required
6415 Overlap_Detected : Boolean := False;
6416 -- Set True if an overlap is detected
6418 Ccount : Natural := 0;
6419 -- Number of component clauses in record rep clause
6421 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
6422 -- Given two entities for record components or discriminants, checks
6423 -- if they have overlapping component clauses and issues errors if so.
6425 procedure Find_Component;
6426 -- Finds component entity corresponding to current component clause (in
6427 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
6428 -- start/stop bits for the field. If there is no matching component or
6429 -- if the matching component does not have a component clause, then
6430 -- that's an error and Comp is set to Empty, but no error message is
6431 -- issued, since the message was already given. Comp is also set to
6432 -- Empty if the current "component clause" is in fact a pragma.
6434 -----------------------------
6435 -- Check_Component_Overlap --
6436 -----------------------------
6438 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
6439 CC1 : constant Node_Id := Component_Clause (C1_Ent);
6440 CC2 : constant Node_Id := Component_Clause (C2_Ent);
6443 if Present (CC1) and then Present (CC2) then
6445 -- Exclude odd case where we have two tag fields in the same
6446 -- record, both at location zero. This seems a bit strange, but
6447 -- it seems to happen in some circumstances, perhaps on an error.
6449 if Chars (C1_Ent) = Name_uTag
6451 Chars (C2_Ent) = Name_uTag
6456 -- Here we check if the two fields overlap
6459 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
6460 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
6461 E1 : constant Uint := S1 + Esize (C1_Ent);
6462 E2 : constant Uint := S2 + Esize (C2_Ent);
6465 if E2 <= S1 or else E1 <= S2 then
6468 Error_Msg_Node_2 := Component_Name (CC2);
6469 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6470 Error_Msg_Node_1 := Component_Name (CC1);
6472 ("component& overlaps & #", Component_Name (CC1));
6473 Overlap_Detected := True;
6477 end Check_Component_Overlap;
6479 --------------------
6480 -- Find_Component --
6481 --------------------
6483 procedure Find_Component is
6485 procedure Search_Component (R : Entity_Id);
6486 -- Search components of R for a match. If found, Comp is set.
6488 ----------------------
6489 -- Search_Component --
6490 ----------------------
6492 procedure Search_Component (R : Entity_Id) is
6494 Comp := First_Component_Or_Discriminant (R);
6495 while Present (Comp) loop
6497 -- Ignore error of attribute name for component name (we
6498 -- already gave an error message for this, so no need to
6501 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
6504 exit when Chars (Comp) = Chars (Component_Name (CC));
6507 Next_Component_Or_Discriminant (Comp);
6509 end Search_Component;
6511 -- Start of processing for Find_Component
6514 -- Return with Comp set to Empty if we have a pragma
6516 if Nkind (CC) = N_Pragma then
6521 -- Search current record for matching component
6523 Search_Component (Rectype);
6525 -- If not found, maybe component of base type that is absent from
6526 -- statically constrained first subtype.
6529 Search_Component (Base_Type (Rectype));
6532 -- If no component, or the component does not reference the component
6533 -- clause in question, then there was some previous error for which
6534 -- we already gave a message, so just return with Comp Empty.
6537 or else Component_Clause (Comp) /= CC
6541 -- Normal case where we have a component clause
6544 Fbit := Component_Bit_Offset (Comp);
6545 Lbit := Fbit + Esize (Comp) - 1;
6549 -- Start of processing for Check_Record_Representation_Clause
6553 Rectype := Entity (Ident);
6555 if Rectype = Any_Type then
6558 Rectype := Underlying_Type (Rectype);
6561 -- See if we have a fully repped derived tagged type
6564 PS : constant Entity_Id := Parent_Subtype (Rectype);
6567 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
6568 Tagged_Parent := PS;
6570 -- Find maximum bit of any component of the parent type
6572 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
6573 Pcomp := First_Entity (Tagged_Parent);
6574 while Present (Pcomp) loop
6575 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
6576 if Component_Bit_Offset (Pcomp) /= No_Uint
6577 and then Known_Static_Esize (Pcomp)
6582 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
6585 Next_Entity (Pcomp);
6591 -- All done if no component clauses
6593 CC := First (Component_Clauses (N));
6599 -- If a tag is present, then create a component clause that places it
6600 -- at the start of the record (otherwise gigi may place it after other
6601 -- fields that have rep clauses).
6603 Fent := First_Entity (Rectype);
6605 if Nkind (Fent) = N_Defining_Identifier
6606 and then Chars (Fent) = Name_uTag
6608 Set_Component_Bit_Offset (Fent, Uint_0);
6609 Set_Normalized_Position (Fent, Uint_0);
6610 Set_Normalized_First_Bit (Fent, Uint_0);
6611 Set_Normalized_Position_Max (Fent, Uint_0);
6612 Init_Esize (Fent, System_Address_Size);
6614 Set_Component_Clause (Fent,
6615 Make_Component_Clause (Loc,
6616 Component_Name => Make_Identifier (Loc, Name_uTag),
6618 Position => Make_Integer_Literal (Loc, Uint_0),
6619 First_Bit => Make_Integer_Literal (Loc, Uint_0),
6621 Make_Integer_Literal (Loc,
6622 UI_From_Int (System_Address_Size))));
6624 Ccount := Ccount + 1;
6627 Max_Bit_So_Far := Uint_Minus_1;
6628 Overlap_Check_Required := False;
6630 -- Process the component clauses
6632 while Present (CC) loop
6635 if Present (Comp) then
6636 Ccount := Ccount + 1;
6638 -- We need a full overlap check if record positions non-monotonic
6640 if Fbit <= Max_Bit_So_Far then
6641 Overlap_Check_Required := True;
6644 Max_Bit_So_Far := Lbit;
6646 -- Check bit position out of range of specified size
6648 if Has_Size_Clause (Rectype)
6649 and then RM_Size (Rectype) <= Lbit
6652 ("bit number out of range of specified size",
6655 -- Check for overlap with tag field
6658 if Is_Tagged_Type (Rectype)
6659 and then Fbit < System_Address_Size
6662 ("component overlaps tag field of&",
6663 Component_Name (CC), Rectype);
6664 Overlap_Detected := True;
6672 -- Check parent overlap if component might overlap parent field
6674 if Present (Tagged_Parent)
6675 and then Fbit <= Parent_Last_Bit
6677 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
6678 while Present (Pcomp) loop
6679 if not Is_Tag (Pcomp)
6680 and then Chars (Pcomp) /= Name_uParent
6682 Check_Component_Overlap (Comp, Pcomp);
6685 Next_Component_Or_Discriminant (Pcomp);
6693 -- Now that we have processed all the component clauses, check for
6694 -- overlap. We have to leave this till last, since the components can
6695 -- appear in any arbitrary order in the representation clause.
6697 -- We do not need this check if all specified ranges were monotonic,
6698 -- as recorded by Overlap_Check_Required being False at this stage.
6700 -- This first section checks if there are any overlapping entries at
6701 -- all. It does this by sorting all entries and then seeing if there are
6702 -- any overlaps. If there are none, then that is decisive, but if there
6703 -- are overlaps, they may still be OK (they may result from fields in
6704 -- different variants).
6706 if Overlap_Check_Required then
6707 Overlap_Check1 : declare
6709 OC_Fbit : array (0 .. Ccount) of Uint;
6710 -- First-bit values for component clauses, the value is the offset
6711 -- of the first bit of the field from start of record. The zero
6712 -- entry is for use in sorting.
6714 OC_Lbit : array (0 .. Ccount) of Uint;
6715 -- Last-bit values for component clauses, the value is the offset
6716 -- of the last bit of the field from start of record. The zero
6717 -- entry is for use in sorting.
6719 OC_Count : Natural := 0;
6720 -- Count of entries in OC_Fbit and OC_Lbit
6722 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6723 -- Compare routine for Sort
6725 procedure OC_Move (From : Natural; To : Natural);
6726 -- Move routine for Sort
6728 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6734 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6736 return OC_Fbit (Op1) < OC_Fbit (Op2);
6743 procedure OC_Move (From : Natural; To : Natural) is
6745 OC_Fbit (To) := OC_Fbit (From);
6746 OC_Lbit (To) := OC_Lbit (From);
6749 -- Start of processing for Overlap_Check
6752 CC := First (Component_Clauses (N));
6753 while Present (CC) loop
6755 -- Exclude component clause already marked in error
6757 if not Error_Posted (CC) then
6760 if Present (Comp) then
6761 OC_Count := OC_Count + 1;
6762 OC_Fbit (OC_Count) := Fbit;
6763 OC_Lbit (OC_Count) := Lbit;
6770 Sorting.Sort (OC_Count);
6772 Overlap_Check_Required := False;
6773 for J in 1 .. OC_Count - 1 loop
6774 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6775 Overlap_Check_Required := True;
6782 -- If Overlap_Check_Required is still True, then we have to do the full
6783 -- scale overlap check, since we have at least two fields that do
6784 -- overlap, and we need to know if that is OK since they are in
6785 -- different variant, or whether we have a definite problem.
6787 if Overlap_Check_Required then
6788 Overlap_Check2 : declare
6789 C1_Ent, C2_Ent : Entity_Id;
6790 -- Entities of components being checked for overlap
6793 -- Component_List node whose Component_Items are being checked
6796 -- Component declaration for component being checked
6799 C1_Ent := First_Entity (Base_Type (Rectype));
6801 -- Loop through all components in record. For each component check
6802 -- for overlap with any of the preceding elements on the component
6803 -- list containing the component and also, if the component is in
6804 -- a variant, check against components outside the case structure.
6805 -- This latter test is repeated recursively up the variant tree.
6807 Main_Component_Loop : while Present (C1_Ent) loop
6808 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6809 goto Continue_Main_Component_Loop;
6812 -- Skip overlap check if entity has no declaration node. This
6813 -- happens with discriminants in constrained derived types.
6814 -- Possibly we are missing some checks as a result, but that
6815 -- does not seem terribly serious.
6817 if No (Declaration_Node (C1_Ent)) then
6818 goto Continue_Main_Component_Loop;
6821 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6823 -- Loop through component lists that need checking. Check the
6824 -- current component list and all lists in variants above us.
6826 Component_List_Loop : loop
6828 -- If derived type definition, go to full declaration
6829 -- If at outer level, check discriminants if there are any.
6831 if Nkind (Clist) = N_Derived_Type_Definition then
6832 Clist := Parent (Clist);
6835 -- Outer level of record definition, check discriminants
6837 if Nkind_In (Clist, N_Full_Type_Declaration,
6838 N_Private_Type_Declaration)
6840 if Has_Discriminants (Defining_Identifier (Clist)) then
6842 First_Discriminant (Defining_Identifier (Clist));
6843 while Present (C2_Ent) loop
6844 exit when C1_Ent = C2_Ent;
6845 Check_Component_Overlap (C1_Ent, C2_Ent);
6846 Next_Discriminant (C2_Ent);
6850 -- Record extension case
6852 elsif Nkind (Clist) = N_Derived_Type_Definition then
6855 -- Otherwise check one component list
6858 Citem := First (Component_Items (Clist));
6859 while Present (Citem) loop
6860 if Nkind (Citem) = N_Component_Declaration then
6861 C2_Ent := Defining_Identifier (Citem);
6862 exit when C1_Ent = C2_Ent;
6863 Check_Component_Overlap (C1_Ent, C2_Ent);
6870 -- Check for variants above us (the parent of the Clist can
6871 -- be a variant, in which case its parent is a variant part,
6872 -- and the parent of the variant part is a component list
6873 -- whose components must all be checked against the current
6874 -- component for overlap).
6876 if Nkind (Parent (Clist)) = N_Variant then
6877 Clist := Parent (Parent (Parent (Clist)));
6879 -- Check for possible discriminant part in record, this
6880 -- is treated essentially as another level in the
6881 -- recursion. For this case the parent of the component
6882 -- list is the record definition, and its parent is the
6883 -- full type declaration containing the discriminant
6886 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6887 Clist := Parent (Parent ((Clist)));
6889 -- If neither of these two cases, we are at the top of
6893 exit Component_List_Loop;
6895 end loop Component_List_Loop;
6897 <<Continue_Main_Component_Loop>>
6898 Next_Entity (C1_Ent);
6900 end loop Main_Component_Loop;
6904 -- The following circuit deals with warning on record holes (gaps). We
6905 -- skip this check if overlap was detected, since it makes sense for the
6906 -- programmer to fix this illegality before worrying about warnings.
6908 if not Overlap_Detected and Warn_On_Record_Holes then
6909 Record_Hole_Check : declare
6910 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6911 -- Full declaration of record type
6913 procedure Check_Component_List
6917 -- Check component list CL for holes. The starting bit should be
6918 -- Sbit. which is zero for the main record component list and set
6919 -- appropriately for recursive calls for variants. DS is set to
6920 -- a list of discriminant specifications to be included in the
6921 -- consideration of components. It is No_List if none to consider.
6923 --------------------------
6924 -- Check_Component_List --
6925 --------------------------
6927 procedure Check_Component_List
6935 Compl := Integer (List_Length (Component_Items (CL)));
6937 if DS /= No_List then
6938 Compl := Compl + Integer (List_Length (DS));
6942 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6943 -- Gather components (zero entry is for sort routine)
6945 Ncomps : Natural := 0;
6946 -- Number of entries stored in Comps (starting at Comps (1))
6949 -- One component item or discriminant specification
6952 -- Starting bit for next component
6960 function Lt (Op1, Op2 : Natural) return Boolean;
6961 -- Compare routine for Sort
6963 procedure Move (From : Natural; To : Natural);
6964 -- Move routine for Sort
6966 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6972 function Lt (Op1, Op2 : Natural) return Boolean is
6974 return Component_Bit_Offset (Comps (Op1))
6976 Component_Bit_Offset (Comps (Op2));
6983 procedure Move (From : Natural; To : Natural) is
6985 Comps (To) := Comps (From);
6989 -- Gather discriminants into Comp
6991 if DS /= No_List then
6992 Citem := First (DS);
6993 while Present (Citem) loop
6994 if Nkind (Citem) = N_Discriminant_Specification then
6996 Ent : constant Entity_Id :=
6997 Defining_Identifier (Citem);
6999 if Ekind (Ent) = E_Discriminant then
7000 Ncomps := Ncomps + 1;
7001 Comps (Ncomps) := Ent;
7010 -- Gather component entities into Comp
7012 Citem := First (Component_Items (CL));
7013 while Present (Citem) loop
7014 if Nkind (Citem) = N_Component_Declaration then
7015 Ncomps := Ncomps + 1;
7016 Comps (Ncomps) := Defining_Identifier (Citem);
7022 -- Now sort the component entities based on the first bit.
7023 -- Note we already know there are no overlapping components.
7025 Sorting.Sort (Ncomps);
7027 -- Loop through entries checking for holes
7030 for J in 1 .. Ncomps loop
7032 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
7034 if Error_Msg_Uint_1 > 0 then
7036 ("?^-bit gap before component&",
7037 Component_Name (Component_Clause (CEnt)), CEnt);
7040 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
7043 -- Process variant parts recursively if present
7045 if Present (Variant_Part (CL)) then
7046 Variant := First (Variants (Variant_Part (CL)));
7047 while Present (Variant) loop
7048 Check_Component_List
7049 (Component_List (Variant), Nbit, No_List);
7054 end Check_Component_List;
7056 -- Start of processing for Record_Hole_Check
7063 if Is_Tagged_Type (Rectype) then
7064 Sbit := UI_From_Int (System_Address_Size);
7069 if Nkind (Decl) = N_Full_Type_Declaration
7070 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
7072 Check_Component_List
7073 (Component_List (Type_Definition (Decl)),
7075 Discriminant_Specifications (Decl));
7078 end Record_Hole_Check;
7081 -- For records that have component clauses for all components, and whose
7082 -- size is less than or equal to 32, we need to know the size in the
7083 -- front end to activate possible packed array processing where the
7084 -- component type is a record.
7086 -- At this stage Hbit + 1 represents the first unused bit from all the
7087 -- component clauses processed, so if the component clauses are
7088 -- complete, then this is the length of the record.
7090 -- For records longer than System.Storage_Unit, and for those where not
7091 -- all components have component clauses, the back end determines the
7092 -- length (it may for example be appropriate to round up the size
7093 -- to some convenient boundary, based on alignment considerations, etc).
7095 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
7097 -- Nothing to do if at least one component has no component clause
7099 Comp := First_Component_Or_Discriminant (Rectype);
7100 while Present (Comp) loop
7101 exit when No (Component_Clause (Comp));
7102 Next_Component_Or_Discriminant (Comp);
7105 -- If we fall out of loop, all components have component clauses
7106 -- and so we can set the size to the maximum value.
7109 Set_RM_Size (Rectype, Hbit + 1);
7112 end Check_Record_Representation_Clause;
7118 procedure Check_Size
7122 Biased : out Boolean)
7124 UT : constant Entity_Id := Underlying_Type (T);
7130 -- Dismiss cases for generic types or types with previous errors
7133 or else UT = Any_Type
7134 or else Is_Generic_Type (UT)
7135 or else Is_Generic_Type (Root_Type (UT))
7139 -- Check case of bit packed array
7141 elsif Is_Array_Type (UT)
7142 and then Known_Static_Component_Size (UT)
7143 and then Is_Bit_Packed_Array (UT)
7151 Asiz := Component_Size (UT);
7152 Indx := First_Index (UT);
7154 Ityp := Etype (Indx);
7156 -- If non-static bound, then we are not in the business of
7157 -- trying to check the length, and indeed an error will be
7158 -- issued elsewhere, since sizes of non-static array types
7159 -- cannot be set implicitly or explicitly.
7161 if not Is_Static_Subtype (Ityp) then
7165 -- Otherwise accumulate next dimension
7167 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
7168 Expr_Value (Type_Low_Bound (Ityp)) +
7172 exit when No (Indx);
7178 Error_Msg_Uint_1 := Asiz;
7180 ("size for& too small, minimum allowed is ^", N, T);
7181 Set_Esize (T, Asiz);
7182 Set_RM_Size (T, Asiz);
7186 -- All other composite types are ignored
7188 elsif Is_Composite_Type (UT) then
7191 -- For fixed-point types, don't check minimum if type is not frozen,
7192 -- since we don't know all the characteristics of the type that can
7193 -- affect the size (e.g. a specified small) till freeze time.
7195 elsif Is_Fixed_Point_Type (UT)
7196 and then not Is_Frozen (UT)
7200 -- Cases for which a minimum check is required
7203 -- Ignore if specified size is correct for the type
7205 if Known_Esize (UT) and then Siz = Esize (UT) then
7209 -- Otherwise get minimum size
7211 M := UI_From_Int (Minimum_Size (UT));
7215 -- Size is less than minimum size, but one possibility remains
7216 -- that we can manage with the new size if we bias the type.
7218 M := UI_From_Int (Minimum_Size (UT, Biased => True));
7221 Error_Msg_Uint_1 := M;
7223 ("size for& too small, minimum allowed is ^", N, T);
7233 -------------------------
7234 -- Get_Alignment_Value --
7235 -------------------------
7237 function Get_Alignment_Value (Expr : Node_Id) return Uint is
7238 Align : constant Uint := Static_Integer (Expr);
7241 if Align = No_Uint then
7244 elsif Align <= 0 then
7245 Error_Msg_N ("alignment value must be positive", Expr);
7249 for J in Int range 0 .. 64 loop
7251 M : constant Uint := Uint_2 ** J;
7254 exit when M = Align;
7258 ("alignment value must be power of 2", Expr);
7266 end Get_Alignment_Value;
7272 procedure Initialize is
7274 Address_Clause_Checks.Init;
7275 Independence_Checks.Init;
7276 Unchecked_Conversions.Init;
7279 -------------------------
7280 -- Is_Operational_Item --
7281 -------------------------
7283 function Is_Operational_Item (N : Node_Id) return Boolean is
7285 if Nkind (N) /= N_Attribute_Definition_Clause then
7289 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
7291 return Id = Attribute_Input
7292 or else Id = Attribute_Output
7293 or else Id = Attribute_Read
7294 or else Id = Attribute_Write
7295 or else Id = Attribute_External_Tag;
7298 end Is_Operational_Item;
7304 function Minimum_Size
7306 Biased : Boolean := False) return Nat
7308 Lo : Uint := No_Uint;
7309 Hi : Uint := No_Uint;
7310 LoR : Ureal := No_Ureal;
7311 HiR : Ureal := No_Ureal;
7312 LoSet : Boolean := False;
7313 HiSet : Boolean := False;
7317 R_Typ : constant Entity_Id := Root_Type (T);
7320 -- If bad type, return 0
7322 if T = Any_Type then
7325 -- For generic types, just return zero. There cannot be any legitimate
7326 -- need to know such a size, but this routine may be called with a
7327 -- generic type as part of normal processing.
7329 elsif Is_Generic_Type (R_Typ)
7330 or else R_Typ = Any_Type
7334 -- Access types. Normally an access type cannot have a size smaller
7335 -- than the size of System.Address. The exception is on VMS, where
7336 -- we have short and long addresses, and it is possible for an access
7337 -- type to have a short address size (and thus be less than the size
7338 -- of System.Address itself). We simply skip the check for VMS, and
7339 -- leave it to the back end to do the check.
7341 elsif Is_Access_Type (T) then
7342 if OpenVMS_On_Target then
7345 return System_Address_Size;
7348 -- Floating-point types
7350 elsif Is_Floating_Point_Type (T) then
7351 return UI_To_Int (Esize (R_Typ));
7355 elsif Is_Discrete_Type (T) then
7357 -- The following loop is looking for the nearest compile time known
7358 -- bounds following the ancestor subtype chain. The idea is to find
7359 -- the most restrictive known bounds information.
7363 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7368 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
7369 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
7376 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
7377 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
7383 Ancest := Ancestor_Subtype (Ancest);
7386 Ancest := Base_Type (T);
7388 if Is_Generic_Type (Ancest) then
7394 -- Fixed-point types. We can't simply use Expr_Value to get the
7395 -- Corresponding_Integer_Value values of the bounds, since these do not
7396 -- get set till the type is frozen, and this routine can be called
7397 -- before the type is frozen. Similarly the test for bounds being static
7398 -- needs to include the case where we have unanalyzed real literals for
7401 elsif Is_Fixed_Point_Type (T) then
7403 -- The following loop is looking for the nearest compile time known
7404 -- bounds following the ancestor subtype chain. The idea is to find
7405 -- the most restrictive known bounds information.
7409 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7413 -- Note: In the following two tests for LoSet and HiSet, it may
7414 -- seem redundant to test for N_Real_Literal here since normally
7415 -- one would assume that the test for the value being known at
7416 -- compile time includes this case. However, there is a glitch.
7417 -- If the real literal comes from folding a non-static expression,
7418 -- then we don't consider any non- static expression to be known
7419 -- at compile time if we are in configurable run time mode (needed
7420 -- in some cases to give a clearer definition of what is and what
7421 -- is not accepted). So the test is indeed needed. Without it, we
7422 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
7425 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
7426 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
7428 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
7435 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
7436 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
7438 HiR := Expr_Value_R (Type_High_Bound (Ancest));
7444 Ancest := Ancestor_Subtype (Ancest);
7447 Ancest := Base_Type (T);
7449 if Is_Generic_Type (Ancest) then
7455 Lo := UR_To_Uint (LoR / Small_Value (T));
7456 Hi := UR_To_Uint (HiR / Small_Value (T));
7458 -- No other types allowed
7461 raise Program_Error;
7464 -- Fall through with Hi and Lo set. Deal with biased case
7467 and then not Is_Fixed_Point_Type (T)
7468 and then not (Is_Enumeration_Type (T)
7469 and then Has_Non_Standard_Rep (T)))
7470 or else Has_Biased_Representation (T)
7476 -- Signed case. Note that we consider types like range 1 .. -1 to be
7477 -- signed for the purpose of computing the size, since the bounds have
7478 -- to be accommodated in the base type.
7480 if Lo < 0 or else Hi < 0 then
7484 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
7485 -- Note that we accommodate the case where the bounds cross. This
7486 -- can happen either because of the way the bounds are declared
7487 -- or because of the algorithm in Freeze_Fixed_Point_Type.
7501 -- If both bounds are positive, make sure that both are represen-
7502 -- table in the case where the bounds are crossed. This can happen
7503 -- either because of the way the bounds are declared, or because of
7504 -- the algorithm in Freeze_Fixed_Point_Type.
7510 -- S = size, (can accommodate 0 .. (2**size - 1))
7513 while Hi >= Uint_2 ** S loop
7521 ---------------------------
7522 -- New_Stream_Subprogram --
7523 ---------------------------
7525 procedure New_Stream_Subprogram
7529 Nam : TSS_Name_Type)
7531 Loc : constant Source_Ptr := Sloc (N);
7532 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
7533 Subp_Id : Entity_Id;
7534 Subp_Decl : Node_Id;
7538 Defer_Declaration : constant Boolean :=
7539 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
7540 -- For a tagged type, there is a declaration for each stream attribute
7541 -- at the freeze point, and we must generate only a completion of this
7542 -- declaration. We do the same for private types, because the full view
7543 -- might be tagged. Otherwise we generate a declaration at the point of
7544 -- the attribute definition clause.
7546 function Build_Spec return Node_Id;
7547 -- Used for declaration and renaming declaration, so that this is
7548 -- treated as a renaming_as_body.
7554 function Build_Spec return Node_Id is
7555 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
7558 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
7561 Subp_Id := Make_Defining_Identifier (Loc, Sname);
7563 -- S : access Root_Stream_Type'Class
7565 Formals := New_List (
7566 Make_Parameter_Specification (Loc,
7567 Defining_Identifier =>
7568 Make_Defining_Identifier (Loc, Name_S),
7570 Make_Access_Definition (Loc,
7573 Designated_Type (Etype (F)), Loc))));
7575 if Nam = TSS_Stream_Input then
7576 Spec := Make_Function_Specification (Loc,
7577 Defining_Unit_Name => Subp_Id,
7578 Parameter_Specifications => Formals,
7579 Result_Definition => T_Ref);
7584 Make_Parameter_Specification (Loc,
7585 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
7586 Out_Present => Out_P,
7587 Parameter_Type => T_Ref));
7590 Make_Procedure_Specification (Loc,
7591 Defining_Unit_Name => Subp_Id,
7592 Parameter_Specifications => Formals);
7598 -- Start of processing for New_Stream_Subprogram
7601 F := First_Formal (Subp);
7603 if Ekind (Subp) = E_Procedure then
7604 Etyp := Etype (Next_Formal (F));
7606 Etyp := Etype (Subp);
7609 -- Prepare subprogram declaration and insert it as an action on the
7610 -- clause node. The visibility for this entity is used to test for
7611 -- visibility of the attribute definition clause (in the sense of
7612 -- 8.3(23) as amended by AI-195).
7614 if not Defer_Declaration then
7616 Make_Subprogram_Declaration (Loc,
7617 Specification => Build_Spec);
7619 -- For a tagged type, there is always a visible declaration for each
7620 -- stream TSS (it is a predefined primitive operation), and the
7621 -- completion of this declaration occurs at the freeze point, which is
7622 -- not always visible at places where the attribute definition clause is
7623 -- visible. So, we create a dummy entity here for the purpose of
7624 -- tracking the visibility of the attribute definition clause itself.
7628 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
7630 Make_Object_Declaration (Loc,
7631 Defining_Identifier => Subp_Id,
7632 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
7635 Insert_Action (N, Subp_Decl);
7636 Set_Entity (N, Subp_Id);
7639 Make_Subprogram_Renaming_Declaration (Loc,
7640 Specification => Build_Spec,
7641 Name => New_Reference_To (Subp, Loc));
7643 if Defer_Declaration then
7644 Set_TSS (Base_Type (Ent), Subp_Id);
7646 Insert_Action (N, Subp_Decl);
7647 Copy_TSS (Subp_Id, Base_Type (Ent));
7649 end New_Stream_Subprogram;
7651 ------------------------
7652 -- Rep_Item_Too_Early --
7653 ------------------------
7655 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
7657 -- Cannot apply non-operational rep items to generic types
7659 if Is_Operational_Item (N) then
7663 and then Is_Generic_Type (Root_Type (T))
7665 Error_Msg_N ("representation item not allowed for generic type", N);
7669 -- Otherwise check for incomplete type
7671 if Is_Incomplete_Or_Private_Type (T)
7672 and then No (Underlying_Type (T))
7674 (Nkind (N) /= N_Pragma
7675 or else Get_Pragma_Id (N) /= Pragma_Import)
7678 ("representation item must be after full type declaration", N);
7681 -- If the type has incomplete components, a representation clause is
7682 -- illegal but stream attributes and Convention pragmas are correct.
7684 elsif Has_Private_Component (T) then
7685 if Nkind (N) = N_Pragma then
7689 ("representation item must appear after type is fully defined",
7696 end Rep_Item_Too_Early;
7698 -----------------------
7699 -- Rep_Item_Too_Late --
7700 -----------------------
7702 function Rep_Item_Too_Late
7705 FOnly : Boolean := False) return Boolean
7708 Parent_Type : Entity_Id;
7711 -- Output the too late message. Note that this is not considered a
7712 -- serious error, since the effect is simply that we ignore the
7713 -- representation clause in this case.
7719 procedure Too_Late is
7721 Error_Msg_N ("|representation item appears too late!", N);
7724 -- Start of processing for Rep_Item_Too_Late
7727 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7728 -- types, which may be frozen if they appear in a representation clause
7729 -- for a local type.
7732 and then not From_With_Type (T)
7735 S := First_Subtype (T);
7737 if Present (Freeze_Node (S)) then
7739 ("?no more representation items for }", Freeze_Node (S), S);
7744 -- Check for case of non-tagged derived type whose parent either has
7745 -- primitive operations, or is a by reference type (RM 13.1(10)).
7749 and then Is_Derived_Type (T)
7750 and then not Is_Tagged_Type (T)
7752 Parent_Type := Etype (Base_Type (T));
7754 if Has_Primitive_Operations (Parent_Type) then
7757 ("primitive operations already defined for&!", N, Parent_Type);
7760 elsif Is_By_Reference_Type (Parent_Type) then
7763 ("parent type & is a by reference type!", N, Parent_Type);
7768 -- No error, link item into head of chain of rep items for the entity,
7769 -- but avoid chaining if we have an overloadable entity, and the pragma
7770 -- is one that can apply to multiple overloaded entities.
7772 if Is_Overloadable (T)
7773 and then Nkind (N) = N_Pragma
7776 Pname : constant Name_Id := Pragma_Name (N);
7778 if Pname = Name_Convention or else
7779 Pname = Name_Import or else
7780 Pname = Name_Export or else
7781 Pname = Name_External or else
7782 Pname = Name_Interface
7789 Record_Rep_Item (T, N);
7791 end Rep_Item_Too_Late;
7793 -------------------------------------
7794 -- Replace_Type_References_Generic --
7795 -------------------------------------
7797 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7799 function Replace_Node (N : Node_Id) return Traverse_Result;
7800 -- Processes a single node in the traversal procedure below, checking
7801 -- if node N should be replaced, and if so, doing the replacement.
7803 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7804 -- This instantiation provides the body of Replace_Type_References
7810 function Replace_Node (N : Node_Id) return Traverse_Result is
7815 -- Case of identifier
7817 if Nkind (N) = N_Identifier then
7819 -- If not the type name, all done with this node
7821 if Chars (N) /= TName then
7824 -- Otherwise do the replacement and we are done with this node
7827 Replace_Type_Reference (N);
7831 -- Case of selected component (which is what a qualification
7832 -- looks like in the unanalyzed tree, which is what we have.
7834 elsif Nkind (N) = N_Selected_Component then
7836 -- If selector name is not our type, keeping going (we might
7837 -- still have an occurrence of the type in the prefix).
7839 if Nkind (Selector_Name (N)) /= N_Identifier
7840 or else Chars (Selector_Name (N)) /= TName
7844 -- Selector name is our type, check qualification
7847 -- Loop through scopes and prefixes, doing comparison
7852 -- Continue if no more scopes or scope with no name
7854 if No (S) or else Nkind (S) not in N_Has_Chars then
7858 -- Do replace if prefix is an identifier matching the
7859 -- scope that we are currently looking at.
7861 if Nkind (P) = N_Identifier
7862 and then Chars (P) = Chars (S)
7864 Replace_Type_Reference (N);
7868 -- Go check scope above us if prefix is itself of the
7869 -- form of a selected component, whose selector matches
7870 -- the scope we are currently looking at.
7872 if Nkind (P) = N_Selected_Component
7873 and then Nkind (Selector_Name (P)) = N_Identifier
7874 and then Chars (Selector_Name (P)) = Chars (S)
7879 -- For anything else, we don't have a match, so keep on
7880 -- going, there are still some weird cases where we may
7881 -- still have a replacement within the prefix.
7889 -- Continue for any other node kind
7897 Replace_Type_Refs (N);
7898 end Replace_Type_References_Generic;
7900 -------------------------
7901 -- Same_Representation --
7902 -------------------------
7904 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7905 T1 : constant Entity_Id := Underlying_Type (Typ1);
7906 T2 : constant Entity_Id := Underlying_Type (Typ2);
7909 -- A quick check, if base types are the same, then we definitely have
7910 -- the same representation, because the subtype specific representation
7911 -- attributes (Size and Alignment) do not affect representation from
7912 -- the point of view of this test.
7914 if Base_Type (T1) = Base_Type (T2) then
7917 elsif Is_Private_Type (Base_Type (T2))
7918 and then Base_Type (T1) = Full_View (Base_Type (T2))
7923 -- Tagged types never have differing representations
7925 if Is_Tagged_Type (T1) then
7929 -- Representations are definitely different if conventions differ
7931 if Convention (T1) /= Convention (T2) then
7935 -- Representations are different if component alignments differ
7937 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7939 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7940 and then Component_Alignment (T1) /= Component_Alignment (T2)
7945 -- For arrays, the only real issue is component size. If we know the
7946 -- component size for both arrays, and it is the same, then that's
7947 -- good enough to know we don't have a change of representation.
7949 if Is_Array_Type (T1) then
7950 if Known_Component_Size (T1)
7951 and then Known_Component_Size (T2)
7952 and then Component_Size (T1) = Component_Size (T2)
7954 if VM_Target = No_VM then
7957 -- In VM targets the representation of arrays with aliased
7958 -- components differs from arrays with non-aliased components
7961 return Has_Aliased_Components (Base_Type (T1))
7963 Has_Aliased_Components (Base_Type (T2));
7968 -- Types definitely have same representation if neither has non-standard
7969 -- representation since default representations are always consistent.
7970 -- If only one has non-standard representation, and the other does not,
7971 -- then we consider that they do not have the same representation. They
7972 -- might, but there is no way of telling early enough.
7974 if Has_Non_Standard_Rep (T1) then
7975 if not Has_Non_Standard_Rep (T2) then
7979 return not Has_Non_Standard_Rep (T2);
7982 -- Here the two types both have non-standard representation, and we need
7983 -- to determine if they have the same non-standard representation.
7985 -- For arrays, we simply need to test if the component sizes are the
7986 -- same. Pragma Pack is reflected in modified component sizes, so this
7987 -- check also deals with pragma Pack.
7989 if Is_Array_Type (T1) then
7990 return Component_Size (T1) = Component_Size (T2);
7992 -- Tagged types always have the same representation, because it is not
7993 -- possible to specify different representations for common fields.
7995 elsif Is_Tagged_Type (T1) then
7998 -- Case of record types
8000 elsif Is_Record_Type (T1) then
8002 -- Packed status must conform
8004 if Is_Packed (T1) /= Is_Packed (T2) then
8007 -- Otherwise we must check components. Typ2 maybe a constrained
8008 -- subtype with fewer components, so we compare the components
8009 -- of the base types.
8012 Record_Case : declare
8013 CD1, CD2 : Entity_Id;
8015 function Same_Rep return Boolean;
8016 -- CD1 and CD2 are either components or discriminants. This
8017 -- function tests whether the two have the same representation
8023 function Same_Rep return Boolean is
8025 if No (Component_Clause (CD1)) then
8026 return No (Component_Clause (CD2));
8030 Present (Component_Clause (CD2))
8032 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
8034 Esize (CD1) = Esize (CD2);
8038 -- Start of processing for Record_Case
8041 if Has_Discriminants (T1) then
8042 CD1 := First_Discriminant (T1);
8043 CD2 := First_Discriminant (T2);
8045 -- The number of discriminants may be different if the
8046 -- derived type has fewer (constrained by values). The
8047 -- invisible discriminants retain the representation of
8048 -- the original, so the discrepancy does not per se
8049 -- indicate a different representation.
8052 and then Present (CD2)
8054 if not Same_Rep then
8057 Next_Discriminant (CD1);
8058 Next_Discriminant (CD2);
8063 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
8064 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
8066 while Present (CD1) loop
8067 if not Same_Rep then
8070 Next_Component (CD1);
8071 Next_Component (CD2);
8079 -- For enumeration types, we must check each literal to see if the
8080 -- representation is the same. Note that we do not permit enumeration
8081 -- representation clauses for Character and Wide_Character, so these
8082 -- cases were already dealt with.
8084 elsif Is_Enumeration_Type (T1) then
8085 Enumeration_Case : declare
8089 L1 := First_Literal (T1);
8090 L2 := First_Literal (T2);
8092 while Present (L1) loop
8093 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
8103 end Enumeration_Case;
8105 -- Any other types have the same representation for these purposes
8110 end Same_Representation;
8116 procedure Set_Biased
8120 Biased : Boolean := True)
8124 Set_Has_Biased_Representation (E);
8126 if Warn_On_Biased_Representation then
8128 ("?" & Msg & " forces biased representation for&", N, E);
8133 --------------------
8134 -- Set_Enum_Esize --
8135 --------------------
8137 procedure Set_Enum_Esize (T : Entity_Id) is
8145 -- Find the minimum standard size (8,16,32,64) that fits
8147 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
8148 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
8151 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
8152 Sz := Standard_Character_Size; -- May be > 8 on some targets
8154 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
8157 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
8160 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
8165 if Hi < Uint_2**08 then
8166 Sz := Standard_Character_Size; -- May be > 8 on some targets
8168 elsif Hi < Uint_2**16 then
8171 elsif Hi < Uint_2**32 then
8174 else pragma Assert (Hi < Uint_2**63);
8179 -- That minimum is the proper size unless we have a foreign convention
8180 -- and the size required is 32 or less, in which case we bump the size
8181 -- up to 32. This is required for C and C++ and seems reasonable for
8182 -- all other foreign conventions.
8184 if Has_Foreign_Convention (T)
8185 and then Esize (T) < Standard_Integer_Size
8187 Init_Esize (T, Standard_Integer_Size);
8193 ------------------------------
8194 -- Validate_Address_Clauses --
8195 ------------------------------
8197 procedure Validate_Address_Clauses is
8199 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
8201 ACCR : Address_Clause_Check_Record
8202 renames Address_Clause_Checks.Table (J);
8213 -- Skip processing of this entry if warning already posted
8215 if not Address_Warning_Posted (ACCR.N) then
8217 Expr := Original_Node (Expression (ACCR.N));
8221 X_Alignment := Alignment (ACCR.X);
8222 Y_Alignment := Alignment (ACCR.Y);
8224 -- Similarly obtain sizes
8226 X_Size := Esize (ACCR.X);
8227 Y_Size := Esize (ACCR.Y);
8229 -- Check for large object overlaying smaller one
8232 and then X_Size > Uint_0
8233 and then X_Size > Y_Size
8236 ("?& overlays smaller object", ACCR.N, ACCR.X);
8238 ("\?program execution may be erroneous", ACCR.N);
8239 Error_Msg_Uint_1 := X_Size;
8241 ("\?size of & is ^", ACCR.N, ACCR.X);
8242 Error_Msg_Uint_1 := Y_Size;
8244 ("\?size of & is ^", ACCR.N, ACCR.Y);
8246 -- Check for inadequate alignment, both of the base object
8247 -- and of the offset, if any.
8249 -- Note: we do not check the alignment if we gave a size
8250 -- warning, since it would likely be redundant.
8252 elsif Y_Alignment /= Uint_0
8253 and then (Y_Alignment < X_Alignment
8256 Nkind (Expr) = N_Attribute_Reference
8258 Attribute_Name (Expr) = Name_Address
8260 Has_Compatible_Alignment
8261 (ACCR.X, Prefix (Expr))
8262 /= Known_Compatible))
8265 ("?specified address for& may be inconsistent "
8269 ("\?program execution may be erroneous (RM 13.3(27))",
8271 Error_Msg_Uint_1 := X_Alignment;
8273 ("\?alignment of & is ^",
8275 Error_Msg_Uint_1 := Y_Alignment;
8277 ("\?alignment of & is ^",
8279 if Y_Alignment >= X_Alignment then
8281 ("\?but offset is not multiple of alignment",
8288 end Validate_Address_Clauses;
8290 ---------------------------
8291 -- Validate_Independence --
8292 ---------------------------
8294 procedure Validate_Independence is
8295 SU : constant Uint := UI_From_Int (System_Storage_Unit);
8303 procedure Check_Array_Type (Atyp : Entity_Id);
8304 -- Checks if the array type Atyp has independent components, and
8305 -- if not, outputs an appropriate set of error messages.
8307 procedure No_Independence;
8308 -- Output message that independence cannot be guaranteed
8310 function OK_Component (C : Entity_Id) return Boolean;
8311 -- Checks one component to see if it is independently accessible, and
8312 -- if so yields True, otherwise yields False if independent access
8313 -- cannot be guaranteed. This is a conservative routine, it only
8314 -- returns True if it knows for sure, it returns False if it knows
8315 -- there is a problem, or it cannot be sure there is no problem.
8317 procedure Reason_Bad_Component (C : Entity_Id);
8318 -- Outputs continuation message if a reason can be determined for
8319 -- the component C being bad.
8321 ----------------------
8322 -- Check_Array_Type --
8323 ----------------------
8325 procedure Check_Array_Type (Atyp : Entity_Id) is
8326 Ctyp : constant Entity_Id := Component_Type (Atyp);
8329 -- OK if no alignment clause, no pack, and no component size
8331 if not Has_Component_Size_Clause (Atyp)
8332 and then not Has_Alignment_Clause (Atyp)
8333 and then not Is_Packed (Atyp)
8338 -- Check actual component size
8340 if not Known_Component_Size (Atyp)
8341 or else not (Addressable (Component_Size (Atyp))
8342 and then Component_Size (Atyp) < 64)
8343 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
8347 -- Bad component size, check reason
8349 if Has_Component_Size_Clause (Atyp) then
8351 Get_Attribute_Definition_Clause
8352 (Atyp, Attribute_Component_Size);
8355 Error_Msg_Sloc := Sloc (P);
8356 Error_Msg_N ("\because of Component_Size clause#", N);
8361 if Is_Packed (Atyp) then
8362 P := Get_Rep_Pragma (Atyp, Name_Pack);
8365 Error_Msg_Sloc := Sloc (P);
8366 Error_Msg_N ("\because of pragma Pack#", N);
8371 -- No reason found, just return
8376 -- Array type is OK independence-wise
8379 end Check_Array_Type;
8381 ---------------------
8382 -- No_Independence --
8383 ---------------------
8385 procedure No_Independence is
8387 if Pragma_Name (N) = Name_Independent then
8389 ("independence cannot be guaranteed for&", N, E);
8392 ("independent components cannot be guaranteed for&", N, E);
8394 end No_Independence;
8400 function OK_Component (C : Entity_Id) return Boolean is
8401 Rec : constant Entity_Id := Scope (C);
8402 Ctyp : constant Entity_Id := Etype (C);
8405 -- OK if no component clause, no Pack, and no alignment clause
8407 if No (Component_Clause (C))
8408 and then not Is_Packed (Rec)
8409 and then not Has_Alignment_Clause (Rec)
8414 -- Here we look at the actual component layout. A component is
8415 -- addressable if its size is a multiple of the Esize of the
8416 -- component type, and its starting position in the record has
8417 -- appropriate alignment, and the record itself has appropriate
8418 -- alignment to guarantee the component alignment.
8420 -- Make sure sizes are static, always assume the worst for any
8421 -- cases where we cannot check static values.
8423 if not (Known_Static_Esize (C)
8424 and then Known_Static_Esize (Ctyp))
8429 -- Size of component must be addressable or greater than 64 bits
8430 -- and a multiple of bytes.
8432 if not Addressable (Esize (C))
8433 and then Esize (C) < Uint_64
8438 -- Check size is proper multiple
8440 if Esize (C) mod Esize (Ctyp) /= 0 then
8444 -- Check alignment of component is OK
8446 if not Known_Component_Bit_Offset (C)
8447 or else Component_Bit_Offset (C) < Uint_0
8448 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
8453 -- Check alignment of record type is OK
8455 if not Known_Alignment (Rec)
8456 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8461 -- All tests passed, component is addressable
8466 --------------------------
8467 -- Reason_Bad_Component --
8468 --------------------------
8470 procedure Reason_Bad_Component (C : Entity_Id) is
8471 Rec : constant Entity_Id := Scope (C);
8472 Ctyp : constant Entity_Id := Etype (C);
8475 -- If component clause present assume that's the problem
8477 if Present (Component_Clause (C)) then
8478 Error_Msg_Sloc := Sloc (Component_Clause (C));
8479 Error_Msg_N ("\because of Component_Clause#", N);
8483 -- If pragma Pack clause present, assume that's the problem
8485 if Is_Packed (Rec) then
8486 P := Get_Rep_Pragma (Rec, Name_Pack);
8489 Error_Msg_Sloc := Sloc (P);
8490 Error_Msg_N ("\because of pragma Pack#", N);
8495 -- See if record has bad alignment clause
8497 if Has_Alignment_Clause (Rec)
8498 and then Known_Alignment (Rec)
8499 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8501 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
8504 Error_Msg_Sloc := Sloc (P);
8505 Error_Msg_N ("\because of Alignment clause#", N);
8509 -- Couldn't find a reason, so return without a message
8512 end Reason_Bad_Component;
8514 -- Start of processing for Validate_Independence
8517 for J in Independence_Checks.First .. Independence_Checks.Last loop
8518 N := Independence_Checks.Table (J).N;
8519 E := Independence_Checks.Table (J).E;
8520 IC := Pragma_Name (N) = Name_Independent_Components;
8522 -- Deal with component case
8524 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
8525 if not OK_Component (E) then
8527 Reason_Bad_Component (E);
8532 -- Deal with record with Independent_Components
8534 if IC and then Is_Record_Type (E) then
8535 Comp := First_Component_Or_Discriminant (E);
8536 while Present (Comp) loop
8537 if not OK_Component (Comp) then
8539 Reason_Bad_Component (Comp);
8543 Next_Component_Or_Discriminant (Comp);
8547 -- Deal with address clause case
8549 if Is_Object (E) then
8550 Addr := Address_Clause (E);
8552 if Present (Addr) then
8554 Error_Msg_Sloc := Sloc (Addr);
8555 Error_Msg_N ("\because of Address clause#", N);
8560 -- Deal with independent components for array type
8562 if IC and then Is_Array_Type (E) then
8563 Check_Array_Type (E);
8566 -- Deal with independent components for array object
8568 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
8569 Check_Array_Type (Etype (E));
8574 end Validate_Independence;
8576 -----------------------------------
8577 -- Validate_Unchecked_Conversion --
8578 -----------------------------------
8580 procedure Validate_Unchecked_Conversion
8582 Act_Unit : Entity_Id)
8589 -- Obtain source and target types. Note that we call Ancestor_Subtype
8590 -- here because the processing for generic instantiation always makes
8591 -- subtypes, and we want the original frozen actual types.
8593 -- If we are dealing with private types, then do the check on their
8594 -- fully declared counterparts if the full declarations have been
8595 -- encountered (they don't have to be visible, but they must exist!)
8597 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
8599 if Is_Private_Type (Source)
8600 and then Present (Underlying_Type (Source))
8602 Source := Underlying_Type (Source);
8605 Target := Ancestor_Subtype (Etype (Act_Unit));
8607 -- If either type is generic, the instantiation happens within a generic
8608 -- unit, and there is nothing to check. The proper check
8609 -- will happen when the enclosing generic is instantiated.
8611 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
8615 if Is_Private_Type (Target)
8616 and then Present (Underlying_Type (Target))
8618 Target := Underlying_Type (Target);
8621 -- Source may be unconstrained array, but not target
8623 if Is_Array_Type (Target)
8624 and then not Is_Constrained (Target)
8627 ("unchecked conversion to unconstrained array not allowed", N);
8631 -- Warn if conversion between two different convention pointers
8633 if Is_Access_Type (Target)
8634 and then Is_Access_Type (Source)
8635 and then Convention (Target) /= Convention (Source)
8636 and then Warn_On_Unchecked_Conversion
8638 -- Give warnings for subprogram pointers only on most targets. The
8639 -- exception is VMS, where data pointers can have different lengths
8640 -- depending on the pointer convention.
8642 if Is_Access_Subprogram_Type (Target)
8643 or else Is_Access_Subprogram_Type (Source)
8644 or else OpenVMS_On_Target
8647 ("?conversion between pointers with different conventions!", N);
8651 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
8652 -- warning when compiling GNAT-related sources.
8654 if Warn_On_Unchecked_Conversion
8655 and then not In_Predefined_Unit (N)
8656 and then RTU_Loaded (Ada_Calendar)
8658 (Chars (Source) = Name_Time
8660 Chars (Target) = Name_Time)
8662 -- If Ada.Calendar is loaded and the name of one of the operands is
8663 -- Time, there is a good chance that this is Ada.Calendar.Time.
8666 Calendar_Time : constant Entity_Id :=
8667 Full_View (RTE (RO_CA_Time));
8669 pragma Assert (Present (Calendar_Time));
8671 if Source = Calendar_Time
8672 or else Target = Calendar_Time
8675 ("?representation of 'Time values may change between " &
8676 "'G'N'A'T versions", N);
8681 -- Make entry in unchecked conversion table for later processing by
8682 -- Validate_Unchecked_Conversions, which will check sizes and alignments
8683 -- (using values set by the back-end where possible). This is only done
8684 -- if the appropriate warning is active.
8686 if Warn_On_Unchecked_Conversion then
8687 Unchecked_Conversions.Append
8688 (New_Val => UC_Entry'
8693 -- If both sizes are known statically now, then back end annotation
8694 -- is not required to do a proper check but if either size is not
8695 -- known statically, then we need the annotation.
8697 if Known_Static_RM_Size (Source)
8698 and then Known_Static_RM_Size (Target)
8702 Back_Annotate_Rep_Info := True;
8706 -- If unchecked conversion to access type, and access type is declared
8707 -- in the same unit as the unchecked conversion, then set the
8708 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
8711 if Is_Access_Type (Target) and then
8712 In_Same_Source_Unit (Target, N)
8714 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
8717 -- Generate N_Validate_Unchecked_Conversion node for back end in
8718 -- case the back end needs to perform special validation checks.
8720 -- Shouldn't this be in Exp_Ch13, since the check only gets done
8721 -- if we have full expansion and the back end is called ???
8724 Make_Validate_Unchecked_Conversion (Sloc (N));
8725 Set_Source_Type (Vnode, Source);
8726 Set_Target_Type (Vnode, Target);
8728 -- If the unchecked conversion node is in a list, just insert before it.
8729 -- If not we have some strange case, not worth bothering about.
8731 if Is_List_Member (N) then
8732 Insert_After (N, Vnode);
8734 end Validate_Unchecked_Conversion;
8736 ------------------------------------
8737 -- Validate_Unchecked_Conversions --
8738 ------------------------------------
8740 procedure Validate_Unchecked_Conversions is
8742 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8744 T : UC_Entry renames Unchecked_Conversions.Table (N);
8746 Eloc : constant Source_Ptr := T.Eloc;
8747 Source : constant Entity_Id := T.Source;
8748 Target : constant Entity_Id := T.Target;
8754 -- This validation check, which warns if we have unequal sizes for
8755 -- unchecked conversion, and thus potentially implementation
8756 -- dependent semantics, is one of the few occasions on which we
8757 -- use the official RM size instead of Esize. See description in
8758 -- Einfo "Handling of Type'Size Values" for details.
8760 if Serious_Errors_Detected = 0
8761 and then Known_Static_RM_Size (Source)
8762 and then Known_Static_RM_Size (Target)
8764 -- Don't do the check if warnings off for either type, note the
8765 -- deliberate use of OR here instead of OR ELSE to get the flag
8766 -- Warnings_Off_Used set for both types if appropriate.
8768 and then not (Has_Warnings_Off (Source)
8770 Has_Warnings_Off (Target))
8772 Source_Siz := RM_Size (Source);
8773 Target_Siz := RM_Size (Target);
8775 if Source_Siz /= Target_Siz then
8777 ("?types for unchecked conversion have different sizes!",
8780 if All_Errors_Mode then
8781 Error_Msg_Name_1 := Chars (Source);
8782 Error_Msg_Uint_1 := Source_Siz;
8783 Error_Msg_Name_2 := Chars (Target);
8784 Error_Msg_Uint_2 := Target_Siz;
8785 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8787 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8789 if Is_Discrete_Type (Source)
8790 and then Is_Discrete_Type (Target)
8792 if Source_Siz > Target_Siz then
8794 ("\?^ high order bits of source will be ignored!",
8797 elsif Is_Unsigned_Type (Source) then
8799 ("\?source will be extended with ^ high order " &
8800 "zero bits?!", Eloc);
8804 ("\?source will be extended with ^ high order " &
8809 elsif Source_Siz < Target_Siz then
8810 if Is_Discrete_Type (Target) then
8811 if Bytes_Big_Endian then
8813 ("\?target value will include ^ undefined " &
8818 ("\?target value will include ^ undefined " &
8825 ("\?^ trailing bits of target value will be " &
8826 "undefined!", Eloc);
8829 else pragma Assert (Source_Siz > Target_Siz);
8831 ("\?^ trailing bits of source will be ignored!",
8838 -- If both types are access types, we need to check the alignment.
8839 -- If the alignment of both is specified, we can do it here.
8841 if Serious_Errors_Detected = 0
8842 and then Ekind (Source) in Access_Kind
8843 and then Ekind (Target) in Access_Kind
8844 and then Target_Strict_Alignment
8845 and then Present (Designated_Type (Source))
8846 and then Present (Designated_Type (Target))
8849 D_Source : constant Entity_Id := Designated_Type (Source);
8850 D_Target : constant Entity_Id := Designated_Type (Target);
8853 if Known_Alignment (D_Source)
8854 and then Known_Alignment (D_Target)
8857 Source_Align : constant Uint := Alignment (D_Source);
8858 Target_Align : constant Uint := Alignment (D_Target);
8861 if Source_Align < Target_Align
8862 and then not Is_Tagged_Type (D_Source)
8864 -- Suppress warning if warnings suppressed on either
8865 -- type or either designated type. Note the use of
8866 -- OR here instead of OR ELSE. That is intentional,
8867 -- we would like to set flag Warnings_Off_Used in
8868 -- all types for which warnings are suppressed.
8870 and then not (Has_Warnings_Off (D_Source)
8872 Has_Warnings_Off (D_Target)
8874 Has_Warnings_Off (Source)
8876 Has_Warnings_Off (Target))
8878 Error_Msg_Uint_1 := Target_Align;
8879 Error_Msg_Uint_2 := Source_Align;
8880 Error_Msg_Node_1 := D_Target;
8881 Error_Msg_Node_2 := D_Source;
8883 ("?alignment of & (^) is stricter than " &
8884 "alignment of & (^)!", Eloc);
8886 ("\?resulting access value may have invalid " &
8887 "alignment!", Eloc);
8895 end Validate_Unchecked_Conversions;
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