1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Disp; use Exp_Disp;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
43 with Rtsfind; use Rtsfind;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Ch3; use Sem_Ch3;
47 with Sem_Ch6; use Sem_Ch6;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Res; use Sem_Res;
51 with Sem_Type; use Sem_Type;
52 with Sem_Util; use Sem_Util;
53 with Sem_Warn; use Sem_Warn;
54 with Sinput; use Sinput;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Stringt; use Stringt;
59 with Targparm; use Targparm;
60 with Ttypes; use Ttypes;
61 with Tbuild; use Tbuild;
62 with Urealp; use Urealp;
64 with GNAT.Heap_Sort_G;
66 package body Sem_Ch13 is
68 SSU : constant Pos := System_Storage_Unit;
69 -- Convenient short hand for commonly used constant
71 -----------------------
72 -- Local Subprograms --
73 -----------------------
75 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id);
76 -- This routine is called after setting the Esize of type entity Typ.
77 -- The purpose is to deal with the situation where an alignment has been
78 -- inherited from a derived type that is no longer appropriate for the
79 -- new Esize value. In this case, we reset the Alignment to unknown.
81 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
82 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
83 -- then either there are pragma Invariant entries on the rep chain for the
84 -- type (note that Predicate aspects are converted to pragam Predicate), or
85 -- there are inherited aspects from a parent type, or ancestor subtypes.
86 -- This procedure builds the spec and body for the Predicate function that
87 -- tests these predicates. N is the freeze node for the type. The spec of
88 -- the function is inserted before the freeze node, and the body of the
89 -- funtion is inserted after the freeze node.
91 procedure Build_Static_Predicate
95 -- Given a predicated type Typ, where Typ is a discrete static subtype,
96 -- whose predicate expression is Expr, tests if Expr is a static predicate,
97 -- and if so, builds the predicate range list. Nam is the name of the one
98 -- argument to the predicate function. Occurrences of the type name in the
99 -- predicate expression have been replaced by identifer references to this
100 -- name, which is unique, so any identifier with Chars matching Nam must be
101 -- a reference to the type. If the predicate is non-static, this procedure
102 -- returns doing nothing. If the predicate is static, then the predicate
103 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
104 -- a canonicalized membership operation.
106 function Get_Alignment_Value (Expr : Node_Id) return Uint;
107 -- Given the expression for an alignment value, returns the corresponding
108 -- Uint value. If the value is inappropriate, then error messages are
109 -- posted as required, and a value of No_Uint is returned.
111 function Is_Operational_Item (N : Node_Id) return Boolean;
112 -- A specification for a stream attribute is allowed before the full type
113 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
114 -- that do not specify a representation characteristic are operational
117 procedure New_Stream_Subprogram
121 Nam : TSS_Name_Type);
122 -- Create a subprogram renaming of a given stream attribute to the
123 -- designated subprogram and then in the tagged case, provide this as a
124 -- primitive operation, or in the non-tagged case make an appropriate TSS
125 -- entry. This is more properly an expansion activity than just semantics,
126 -- but the presence of user-defined stream functions for limited types is a
127 -- legality check, which is why this takes place here rather than in
128 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
129 -- function to be generated.
131 -- To avoid elaboration anomalies with freeze nodes, for untagged types
132 -- we generate both a subprogram declaration and a subprogram renaming
133 -- declaration, so that the attribute specification is handled as a
134 -- renaming_as_body. For tagged types, the specification is one of the
138 with procedure Replace_Type_Reference (N : Node_Id);
139 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
140 -- This is used to scan an expression for a predicate or invariant aspect
141 -- replacing occurrences of the name TName (the name of the subtype to
142 -- which the aspect applies) with appropriate references to the parameter
143 -- of the predicate function or invariant procedure. The procedure passed
144 -- as a generic parameter does the actual replacement of node N, which is
145 -- either a simple direct reference to TName, or a selected component that
146 -- represents an appropriately qualified occurrence of TName.
152 Biased : Boolean := True);
153 -- If Biased is True, sets Has_Biased_Representation flag for E, and
154 -- outputs a warning message at node N if Warn_On_Biased_Representation is
155 -- is True. This warning inserts the string Msg to describe the construct
158 ----------------------------------------------
159 -- Table for Validate_Unchecked_Conversions --
160 ----------------------------------------------
162 -- The following table collects unchecked conversions for validation.
163 -- Entries are made by Validate_Unchecked_Conversion and then the
164 -- call to Validate_Unchecked_Conversions does the actual error
165 -- checking and posting of warnings. The reason for this delayed
166 -- processing is to take advantage of back-annotations of size and
167 -- alignment values performed by the back end.
169 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
170 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
171 -- will already have modified all Sloc values if the -gnatD option is set.
173 type UC_Entry is record
174 Eloc : Source_Ptr; -- node used for posting warnings
175 Source : Entity_Id; -- source type for unchecked conversion
176 Target : Entity_Id; -- target type for unchecked conversion
179 package Unchecked_Conversions is new Table.Table (
180 Table_Component_Type => UC_Entry,
181 Table_Index_Type => Int,
182 Table_Low_Bound => 1,
184 Table_Increment => 200,
185 Table_Name => "Unchecked_Conversions");
187 ----------------------------------------
188 -- Table for Validate_Address_Clauses --
189 ----------------------------------------
191 -- If an address clause has the form
193 -- for X'Address use Expr
195 -- where Expr is of the form Y'Address or recursively is a reference
196 -- to a constant of either of these forms, and X and Y are entities of
197 -- objects, then if Y has a smaller alignment than X, that merits a
198 -- warning about possible bad alignment. The following table collects
199 -- address clauses of this kind. We put these in a table so that they
200 -- can be checked after the back end has completed annotation of the
201 -- alignments of objects, since we can catch more cases that way.
203 type Address_Clause_Check_Record is record
205 -- The address clause
208 -- The entity of the object overlaying Y
211 -- The entity of the object being overlaid
214 -- Whether the address is offseted within Y
217 package Address_Clause_Checks is new Table.Table (
218 Table_Component_Type => Address_Clause_Check_Record,
219 Table_Index_Type => Int,
220 Table_Low_Bound => 1,
222 Table_Increment => 200,
223 Table_Name => "Address_Clause_Checks");
225 -----------------------------------------
226 -- Adjust_Record_For_Reverse_Bit_Order --
227 -----------------------------------------
229 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
234 -- Processing depends on version of Ada
236 -- For Ada 95, we just renumber bits within a storage unit. We do the
237 -- same for Ada 83 mode, since we recognize pragma Bit_Order in Ada 83,
238 -- and are free to add this extension.
240 if Ada_Version < Ada_2005 then
241 Comp := First_Component_Or_Discriminant (R);
242 while Present (Comp) loop
243 CC := Component_Clause (Comp);
245 -- If component clause is present, then deal with the non-default
246 -- bit order case for Ada 95 mode.
248 -- We only do this processing for the base type, and in fact that
249 -- is important, since otherwise if there are record subtypes, we
250 -- could reverse the bits once for each subtype, which is wrong.
253 and then Ekind (R) = E_Record_Type
256 CFB : constant Uint := Component_Bit_Offset (Comp);
257 CSZ : constant Uint := Esize (Comp);
258 CLC : constant Node_Id := Component_Clause (Comp);
259 Pos : constant Node_Id := Position (CLC);
260 FB : constant Node_Id := First_Bit (CLC);
262 Storage_Unit_Offset : constant Uint :=
263 CFB / System_Storage_Unit;
265 Start_Bit : constant Uint :=
266 CFB mod System_Storage_Unit;
269 -- Cases where field goes over storage unit boundary
271 if Start_Bit + CSZ > System_Storage_Unit then
273 -- Allow multi-byte field but generate warning
275 if Start_Bit mod System_Storage_Unit = 0
276 and then CSZ mod System_Storage_Unit = 0
279 ("multi-byte field specified with non-standard"
280 & " Bit_Order?", CLC);
282 if Bytes_Big_Endian then
284 ("bytes are not reversed "
285 & "(component is big-endian)?", CLC);
288 ("bytes are not reversed "
289 & "(component is little-endian)?", CLC);
292 -- Do not allow non-contiguous field
296 ("attempt to specify non-contiguous field "
297 & "not permitted", CLC);
299 ("\caused by non-standard Bit_Order "
302 ("\consider possibility of using "
303 & "Ada 2005 mode here", CLC);
306 -- Case where field fits in one storage unit
309 -- Give warning if suspicious component clause
311 if Intval (FB) >= System_Storage_Unit
312 and then Warn_On_Reverse_Bit_Order
315 ("?Bit_Order clause does not affect " &
316 "byte ordering", Pos);
318 Intval (Pos) + Intval (FB) /
321 ("?position normalized to ^ before bit " &
322 "order interpreted", Pos);
325 -- Here is where we fix up the Component_Bit_Offset value
326 -- to account for the reverse bit order. Some examples of
327 -- what needs to be done are:
329 -- First_Bit .. Last_Bit Component_Bit_Offset
341 -- The rule is that the first bit is is obtained by
342 -- subtracting the old ending bit from storage_unit - 1.
344 Set_Component_Bit_Offset
346 (Storage_Unit_Offset * System_Storage_Unit) +
347 (System_Storage_Unit - 1) -
348 (Start_Bit + CSZ - 1));
350 Set_Normalized_First_Bit
352 Component_Bit_Offset (Comp) mod
353 System_Storage_Unit);
358 Next_Component_Or_Discriminant (Comp);
361 -- For Ada 2005, we do machine scalar processing, as fully described In
362 -- AI-133. This involves gathering all components which start at the
363 -- same byte offset and processing them together. Same approach is still
364 -- valid in later versions including Ada 2012.
368 Max_Machine_Scalar_Size : constant Uint :=
370 (Standard_Long_Long_Integer_Size);
371 -- We use this as the maximum machine scalar size
374 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
377 -- This first loop through components does two things. First it
378 -- deals with the case of components with component clauses whose
379 -- length is greater than the maximum machine scalar size (either
380 -- accepting them or rejecting as needed). Second, it counts the
381 -- number of components with component clauses whose length does
382 -- not exceed this maximum for later processing.
385 Comp := First_Component_Or_Discriminant (R);
386 while Present (Comp) loop
387 CC := Component_Clause (Comp);
391 Fbit : constant Uint :=
392 Static_Integer (First_Bit (CC));
393 Lbit : constant Uint :=
394 Static_Integer (Last_Bit (CC));
397 -- Case of component with last bit >= max machine scalar
399 if Lbit >= Max_Machine_Scalar_Size then
401 -- This is allowed only if first bit is zero, and
402 -- last bit + 1 is a multiple of storage unit size.
404 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
406 -- This is the case to give a warning if enabled
408 if Warn_On_Reverse_Bit_Order then
410 ("multi-byte field specified with "
411 & " non-standard Bit_Order?", CC);
413 if Bytes_Big_Endian then
415 ("\bytes are not reversed "
416 & "(component is big-endian)?", CC);
419 ("\bytes are not reversed "
420 & "(component is little-endian)?", CC);
424 -- Give error message for RM 13.4.1(10) violation
428 ("machine scalar rules not followed for&",
429 First_Bit (CC), Comp);
431 Error_Msg_Uint_1 := Lbit;
432 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
434 ("\last bit (^) exceeds maximum machine "
438 if (Lbit + 1) mod SSU /= 0 then
439 Error_Msg_Uint_1 := SSU;
441 ("\and is not a multiple of Storage_Unit (^) "
442 & "('R'M 13.4.1(10))",
446 Error_Msg_Uint_1 := Fbit;
448 ("\and first bit (^) is non-zero "
449 & "('R'M 13.4.1(10))",
454 -- OK case of machine scalar related component clause,
455 -- For now, just count them.
458 Num_CC := Num_CC + 1;
463 Next_Component_Or_Discriminant (Comp);
466 -- We need to sort the component clauses on the basis of the
467 -- Position values in the clause, so we can group clauses with
468 -- the same Position. together to determine the relevant machine
472 Comps : array (0 .. Num_CC) of Entity_Id;
473 -- Array to collect component and discriminant entities. The
474 -- data starts at index 1, the 0'th entry is for the sort
477 function CP_Lt (Op1, Op2 : Natural) return Boolean;
478 -- Compare routine for Sort
480 procedure CP_Move (From : Natural; To : Natural);
481 -- Move routine for Sort
483 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
487 -- Start and stop positions in the component list of the set of
488 -- components with the same starting position (that constitute
489 -- components in a single machine scalar).
492 -- Maximum last bit value of any component in this set
495 -- Corresponding machine scalar size
501 function CP_Lt (Op1, Op2 : Natural) return Boolean is
503 return Position (Component_Clause (Comps (Op1))) <
504 Position (Component_Clause (Comps (Op2)));
511 procedure CP_Move (From : Natural; To : Natural) is
513 Comps (To) := Comps (From);
516 -- Start of processing for Sort_CC
519 -- Collect the machine scalar relevant component clauses
522 Comp := First_Component_Or_Discriminant (R);
523 while Present (Comp) loop
525 CC : constant Node_Id := Component_Clause (Comp);
528 -- Collect only component clauses whose last bit is less
529 -- than machine scalar size. Any component clause whose
530 -- last bit exceeds this value does not take part in
531 -- machine scalar layout considerations. The test for
532 -- Error_Posted makes sure we exclude component clauses
533 -- for which we already posted an error.
536 and then not Error_Posted (Last_Bit (CC))
537 and then Static_Integer (Last_Bit (CC)) <
538 Max_Machine_Scalar_Size
540 Num_CC := Num_CC + 1;
541 Comps (Num_CC) := Comp;
545 Next_Component_Or_Discriminant (Comp);
548 -- Sort by ascending position number
550 Sorting.Sort (Num_CC);
552 -- We now have all the components whose size does not exceed
553 -- the max machine scalar value, sorted by starting position.
554 -- In this loop we gather groups of clauses starting at the
555 -- same position, to process them in accordance with AI-133.
558 while Stop < Num_CC loop
563 (Last_Bit (Component_Clause (Comps (Start))));
564 while Stop < Num_CC loop
566 (Position (Component_Clause (Comps (Stop + 1)))) =
568 (Position (Component_Clause (Comps (Stop))))
576 (Component_Clause (Comps (Stop)))));
582 -- Now we have a group of component clauses from Start to
583 -- Stop whose positions are identical, and MaxL is the
584 -- maximum last bit value of any of these components.
586 -- We need to determine the corresponding machine scalar
587 -- size. This loop assumes that machine scalar sizes are
588 -- even, and that each possible machine scalar has twice
589 -- as many bits as the next smaller one.
591 MSS := Max_Machine_Scalar_Size;
593 and then (MSS / 2) >= SSU
594 and then (MSS / 2) > MaxL
599 -- Here is where we fix up the Component_Bit_Offset value
600 -- to account for the reverse bit order. Some examples of
601 -- what needs to be done for the case of a machine scalar
604 -- First_Bit .. Last_Bit Component_Bit_Offset
616 -- The rule is that the first bit is obtained by subtracting
617 -- the old ending bit from machine scalar size - 1.
619 for C in Start .. Stop loop
621 Comp : constant Entity_Id := Comps (C);
622 CC : constant Node_Id :=
623 Component_Clause (Comp);
624 LB : constant Uint :=
625 Static_Integer (Last_Bit (CC));
626 NFB : constant Uint := MSS - Uint_1 - LB;
627 NLB : constant Uint := NFB + Esize (Comp) - 1;
628 Pos : constant Uint :=
629 Static_Integer (Position (CC));
632 if Warn_On_Reverse_Bit_Order then
633 Error_Msg_Uint_1 := MSS;
635 ("info: reverse bit order in machine " &
636 "scalar of length^?", First_Bit (CC));
637 Error_Msg_Uint_1 := NFB;
638 Error_Msg_Uint_2 := NLB;
640 if Bytes_Big_Endian then
642 ("?\info: big-endian range for "
643 & "component & is ^ .. ^",
644 First_Bit (CC), Comp);
647 ("?\info: little-endian range "
648 & "for component & is ^ .. ^",
649 First_Bit (CC), Comp);
653 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
654 Set_Normalized_First_Bit (Comp, NFB mod SSU);
661 end Adjust_Record_For_Reverse_Bit_Order;
663 --------------------------------------
664 -- Alignment_Check_For_Esize_Change --
665 --------------------------------------
667 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id) is
669 -- If the alignment is known, and not set by a rep clause, and is
670 -- inconsistent with the size being set, then reset it to unknown,
671 -- we assume in this case that the size overrides the inherited
672 -- alignment, and that the alignment must be recomputed.
674 if Known_Alignment (Typ)
675 and then not Has_Alignment_Clause (Typ)
676 and then Esize (Typ) mod (Alignment (Typ) * SSU) /= 0
678 Init_Alignment (Typ);
680 end Alignment_Check_For_Esize_Change;
682 -----------------------------------
683 -- Analyze_Aspect_Specifications --
684 -----------------------------------
686 procedure Analyze_Aspect_Specifications
695 Ins_Node : Node_Id := N;
696 -- Insert pragmas (except Pre/Post/Invariant/Predicate) after this node
698 -- The general processing involves building an attribute definition
699 -- clause or a pragma node that corresponds to the access type. Then
700 -- one of two things happens:
702 -- If we are required to delay the evaluation of this aspect to the
703 -- freeze point, we preanalyze the relevant argument, and then attach
704 -- the corresponding pragma/attribute definition clause to the aspect
705 -- specification node, which is then placed in the Rep Item chain.
706 -- In this case we mark the entity with the Has_Delayed_Aspects flag,
707 -- and we evaluate the rep item at the freeze point.
709 -- If no delay is required, we just insert the pragma or attribute
710 -- after the declaration, and it will get processed by the normal
711 -- circuit. The From_Aspect_Specification flag is set on the pragma
712 -- or attribute definition node in either case to activate special
713 -- processing (e.g. not traversing the list of homonyms for inline).
715 Delay_Required : Boolean;
716 -- Set True if delay is required
719 -- Return if no aspects
725 -- Return if already analyzed (avoids duplicate calls in some cases
726 -- where type declarations get rewritten and proessed twice).
732 -- Loop through apsects
735 while Present (Aspect) loop
737 Loc : constant Source_Ptr := Sloc (Aspect);
738 Id : constant Node_Id := Identifier (Aspect);
739 Expr : constant Node_Id := Expression (Aspect);
740 Nam : constant Name_Id := Chars (Id);
741 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
745 Eloc : Source_Ptr := Sloc (Expr);
746 -- Source location of expression, modified when we split PPC's
749 Set_Entity (Aspect, E);
750 Ent := New_Occurrence_Of (E, Sloc (Id));
752 -- Check for duplicate aspect. Note that the Comes_From_Source
753 -- test allows duplicate Pre/Post's that we generate internally
754 -- to escape being flagged here.
757 while Anod /= Aspect loop
758 if Nam = Chars (Identifier (Anod))
759 and then Comes_From_Source (Aspect)
761 Error_Msg_Name_1 := Nam;
762 Error_Msg_Sloc := Sloc (Anod);
764 -- Case of same aspect specified twice
766 if Class_Present (Anod) = Class_Present (Aspect) then
767 if not Class_Present (Anod) then
769 ("aspect% for & previously given#",
773 ("aspect `%''Class` for & previously given#",
777 -- Case of Pre and Pre'Class both specified
779 elsif Nam = Name_Pre then
780 if Class_Present (Aspect) then
782 ("aspect `Pre''Class` for & is not allowed here",
785 ("\since aspect `Pre` previously given#",
790 ("aspect `Pre` for & is not allowed here",
793 ("\since aspect `Pre''Class` previously given#",
804 -- Processing based on specific aspect
808 -- No_Aspect should be impossible
813 -- Aspects taking an optional boolean argument. For all of
814 -- these we just create a matching pragma and insert it,
815 -- setting flag Cancel_Aspect if the expression is False.
817 when Aspect_Ada_2005 |
820 Aspect_Atomic_Components |
821 Aspect_Discard_Names |
822 Aspect_Favor_Top_Level |
824 Aspect_Inline_Always |
827 Aspect_Persistent_BSS |
828 Aspect_Preelaborable_Initialization |
829 Aspect_Pure_Function |
831 Aspect_Suppress_Debug_Info |
832 Aspect_Unchecked_Union |
833 Aspect_Universal_Aliasing |
835 Aspect_Unreferenced |
836 Aspect_Unreferenced_Objects |
838 Aspect_Volatile_Components =>
840 -- Build corresponding pragma node
844 Pragma_Argument_Associations => New_List (Ent),
846 Make_Identifier (Sloc (Id), Chars (Id)));
848 -- Deal with missing expression case, delay never needed
851 Delay_Required := False;
853 -- Expression is present
856 Preanalyze_Spec_Expression (Expr, Standard_Boolean);
858 -- If preanalysis gives a static expression, we don't
859 -- need to delay (this will happen often in practice).
861 if Is_OK_Static_Expression (Expr) then
862 Delay_Required := False;
864 if Is_False (Expr_Value (Expr)) then
865 Set_Aspect_Cancel (Aitem);
868 -- If we don't get a static expression, then delay, the
869 -- expression may turn out static by freeze time.
872 Delay_Required := True;
876 -- Aspects corresponding to attribute definition clauses
878 when Aspect_Address |
881 Aspect_Component_Size |
882 Aspect_External_Tag |
883 Aspect_Machine_Radix |
886 Aspect_Storage_Pool |
887 Aspect_Storage_Size |
891 -- Preanalyze the expression with the appropriate type
894 when Aspect_Address =>
895 T := RTE (RE_Address);
896 when Aspect_Bit_Order =>
897 T := RTE (RE_Bit_Order);
898 when Aspect_External_Tag =>
899 T := Standard_String;
900 when Aspect_Storage_Pool =>
901 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
906 Preanalyze_Spec_Expression (Expr, T);
908 -- Construct the attribute definition clause
911 Make_Attribute_Definition_Clause (Loc,
914 Expression => Relocate_Node (Expr));
916 -- We do not need a delay if we have a static expression
918 if Is_OK_Static_Expression (Expression (Aitem)) then
919 Delay_Required := False;
921 -- Here a delay is required
924 Delay_Required := True;
927 -- Aspects corresponding to pragmas with two arguments, where
928 -- the first argument is a local name referring to the entity,
929 -- and the second argument is the aspect definition expression.
931 when Aspect_Suppress |
934 -- Construct the pragma
938 Pragma_Argument_Associations => New_List (
939 New_Occurrence_Of (E, Eloc),
940 Relocate_Node (Expr)),
942 Make_Identifier (Sloc (Id), Chars (Id)));
944 -- We don't have to play the delay game here, since the only
945 -- values are check names which don't get analyzed anyway.
947 Delay_Required := False;
949 -- Aspects corresponding to stream routines
956 -- Construct the attribute definition clause
959 Make_Attribute_Definition_Clause (Loc,
962 Expression => Relocate_Node (Expr));
964 -- These are always delayed (typically the subprogram that
965 -- is referenced cannot have been declared yet, since it has
966 -- a reference to the type for which this aspect is defined.
968 Delay_Required := True;
970 -- Aspects corresponding to pragmas with two arguments, where
971 -- the second argument is a local name referring to the entity,
972 -- and the first argument is the aspect definition expression.
974 when Aspect_Warnings =>
976 -- Construct the pragma
980 Pragma_Argument_Associations => New_List (
981 Relocate_Node (Expr),
982 New_Occurrence_Of (E, Eloc)),
984 Make_Identifier (Sloc (Id), Chars (Id)),
985 Class_Present => Class_Present (Aspect));
987 -- We don't have to play the delay game here, since the only
988 -- values are check names which don't get analyzed anyway.
990 Delay_Required := False;
992 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
993 -- with a first argument that is the expression, and a second
994 -- argument that is an informative message if the test fails.
995 -- This is inserted right after the declaration, to get the
996 -- required pragma placement. The processing for the pragmas
997 -- takes care of the required delay.
999 when Aspect_Pre | Aspect_Post => declare
1003 if A_Id = Aspect_Pre then
1004 Pname := Name_Precondition;
1006 Pname := Name_Postcondition;
1009 -- If the expressions is of the form A and then B, then
1010 -- we generate separate Pre/Post aspects for the separate
1011 -- clauses. Since we allow multiple pragmas, there is no
1012 -- problem in allowing multiple Pre/Post aspects internally.
1014 -- We do not do this for Pre'Class, since we have to put
1015 -- these conditions together in a complex OR expression
1017 if Pname = Name_Postcondition
1018 or else not Class_Present (Aspect)
1020 while Nkind (Expr) = N_And_Then loop
1021 Insert_After (Aspect,
1022 Make_Aspect_Specification (Sloc (Right_Opnd (Expr)),
1023 Identifier => Identifier (Aspect),
1024 Expression => Relocate_Node (Right_Opnd (Expr)),
1025 Class_Present => Class_Present (Aspect),
1026 Split_PPC => True));
1027 Rewrite (Expr, Relocate_Node (Left_Opnd (Expr)));
1028 Eloc := Sloc (Expr);
1032 -- Build the precondition/postcondition pragma
1036 Pragma_Identifier =>
1037 Make_Identifier (Sloc (Id), Pname),
1038 Class_Present => Class_Present (Aspect),
1039 Split_PPC => Split_PPC (Aspect),
1040 Pragma_Argument_Associations => New_List (
1041 Make_Pragma_Argument_Association (Eloc,
1042 Chars => Name_Check,
1043 Expression => Relocate_Node (Expr))));
1045 -- Add message unless exception messages are suppressed
1047 if not Opt.Exception_Locations_Suppressed then
1048 Append_To (Pragma_Argument_Associations (Aitem),
1049 Make_Pragma_Argument_Association (Eloc,
1050 Chars => Name_Message,
1052 Make_String_Literal (Eloc,
1054 & Get_Name_String (Pname)
1056 & Build_Location_String (Eloc))));
1059 Set_From_Aspect_Specification (Aitem, True);
1061 -- For Pre/Post cases, insert immediately after the entity
1062 -- declaration, since that is the required pragma placement.
1063 -- Note that for these aspects, we do not have to worry
1064 -- about delay issues, since the pragmas themselves deal
1065 -- with delay of visibility for the expression analysis.
1067 -- If the entity is a library-level subprogram, the pre/
1068 -- postconditions must be treated as late pragmas.
1070 if Nkind (Parent (N)) = N_Compilation_Unit then
1071 Add_Global_Declaration (Aitem);
1073 Insert_After (N, Aitem);
1079 -- Invariant aspects generate a corresponding pragma with a
1080 -- first argument that is the entity, and the second argument
1081 -- is the expression and anthird argument with an appropriate
1082 -- message. This is inserted right after the declaration, to
1083 -- get the required pragma placement. The pragma processing
1084 -- takes care of the required delay.
1086 when Aspect_Invariant =>
1088 -- Construct the pragma
1092 Pragma_Argument_Associations =>
1093 New_List (Ent, Relocate_Node (Expr)),
1094 Class_Present => Class_Present (Aspect),
1095 Pragma_Identifier =>
1096 Make_Identifier (Sloc (Id), Name_Invariant));
1098 -- Add message unless exception messages are suppressed
1100 if not Opt.Exception_Locations_Suppressed then
1101 Append_To (Pragma_Argument_Associations (Aitem),
1102 Make_Pragma_Argument_Association (Eloc,
1103 Chars => Name_Message,
1105 Make_String_Literal (Eloc,
1106 Strval => "failed invariant from "
1107 & Build_Location_String (Eloc))));
1110 Set_From_Aspect_Specification (Aitem, True);
1112 -- For Invariant case, insert immediately after the entity
1113 -- declaration. We do not have to worry about delay issues
1114 -- since the pragma processing takes care of this.
1116 Insert_After (N, Aitem);
1119 -- Predicate aspects generate a corresponding pragma with a
1120 -- first argument that is the entity, and the second argument
1121 -- is the expression. This is inserted immediately after the
1122 -- declaration, to get the required pragma placement. The
1123 -- pragma processing takes care of the required delay.
1125 when Aspect_Predicate =>
1127 -- Construct the pragma
1131 Pragma_Argument_Associations =>
1132 New_List (Ent, Relocate_Node (Expr)),
1133 Class_Present => Class_Present (Aspect),
1134 Pragma_Identifier =>
1135 Make_Identifier (Sloc (Id), Name_Predicate));
1137 Set_From_Aspect_Specification (Aitem, True);
1139 -- Make sure we have a freeze node (it might otherwise be
1140 -- missing in cases like subtype X is Y, and we would not
1141 -- have a place to build the predicate function).
1143 Ensure_Freeze_Node (E);
1145 -- For Predicate case, insert immediately after the entity
1146 -- declaration. We do not have to worry about delay issues
1147 -- since the pragma processing takes care of this.
1149 Insert_After (N, Aitem);
1153 Set_From_Aspect_Specification (Aitem, True);
1155 -- If a delay is required, we delay the freeze (not much point in
1156 -- delaying the aspect if we don't delay the freeze!). The pragma
1157 -- or clause is then attached to the aspect specification which
1158 -- is placed in the rep item list.
1160 if Delay_Required then
1161 Ensure_Freeze_Node (E);
1162 Set_Is_Delayed_Aspect (Aitem);
1163 Set_Has_Delayed_Aspects (E);
1164 Set_Aspect_Rep_Item (Aspect, Aitem);
1165 Record_Rep_Item (E, Aspect);
1167 -- If no delay required, insert the pragma/clause in the tree
1170 -- For Pre/Post cases, insert immediately after the entity
1171 -- declaration, since that is the required pragma placement.
1173 if A_Id = Aspect_Pre or else A_Id = Aspect_Post then
1174 Insert_After (N, Aitem);
1176 -- For all other cases, insert in sequence
1179 Insert_After (Ins_Node, Aitem);
1188 end Analyze_Aspect_Specifications;
1190 -----------------------
1191 -- Analyze_At_Clause --
1192 -----------------------
1194 -- An at clause is replaced by the corresponding Address attribute
1195 -- definition clause that is the preferred approach in Ada 95.
1197 procedure Analyze_At_Clause (N : Node_Id) is
1198 CS : constant Boolean := Comes_From_Source (N);
1201 -- This is an obsolescent feature
1203 Check_Restriction (No_Obsolescent_Features, N);
1205 if Warn_On_Obsolescent_Feature then
1207 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1209 ("\use address attribute definition clause instead?", N);
1212 -- Rewrite as address clause
1215 Make_Attribute_Definition_Clause (Sloc (N),
1216 Name => Identifier (N),
1217 Chars => Name_Address,
1218 Expression => Expression (N)));
1220 -- We preserve Comes_From_Source, since logically the clause still
1221 -- comes from the source program even though it is changed in form.
1223 Set_Comes_From_Source (N, CS);
1225 -- Analyze rewritten clause
1227 Analyze_Attribute_Definition_Clause (N);
1228 end Analyze_At_Clause;
1230 -----------------------------------------
1231 -- Analyze_Attribute_Definition_Clause --
1232 -----------------------------------------
1234 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1235 Loc : constant Source_Ptr := Sloc (N);
1236 Nam : constant Node_Id := Name (N);
1237 Attr : constant Name_Id := Chars (N);
1238 Expr : constant Node_Id := Expression (N);
1239 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1243 FOnly : Boolean := False;
1244 -- Reset to True for subtype specific attribute (Alignment, Size)
1245 -- and for stream attributes, i.e. those cases where in the call
1246 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1247 -- rules are checked. Note that the case of stream attributes is not
1248 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1249 -- disallow Storage_Size for derived task types, but that is also
1250 -- clearly unintentional.
1252 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1253 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1254 -- definition clauses.
1256 function Duplicate_Clause return Boolean;
1257 -- This routine checks if the aspect for U_Ent being given by attribute
1258 -- definition clause N is for an aspect that has already been specified,
1259 -- and if so gives an error message. If there is a duplicate, True is
1260 -- returned, otherwise if there is no error, False is returned.
1262 -----------------------------------
1263 -- Analyze_Stream_TSS_Definition --
1264 -----------------------------------
1266 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1267 Subp : Entity_Id := Empty;
1272 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1274 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1275 -- Return true if the entity is a subprogram with an appropriate
1276 -- profile for the attribute being defined.
1278 ----------------------
1279 -- Has_Good_Profile --
1280 ----------------------
1282 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1284 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1285 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1286 (False => E_Procedure, True => E_Function);
1290 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1294 F := First_Formal (Subp);
1297 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1298 or else Designated_Type (Etype (F)) /=
1299 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1304 if not Is_Function then
1308 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1309 (False => E_In_Parameter,
1310 True => E_Out_Parameter);
1312 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1320 Typ := Etype (Subp);
1323 return Base_Type (Typ) = Base_Type (Ent)
1324 and then No (Next_Formal (F));
1325 end Has_Good_Profile;
1327 -- Start of processing for Analyze_Stream_TSS_Definition
1332 if not Is_Type (U_Ent) then
1333 Error_Msg_N ("local name must be a subtype", Nam);
1337 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1339 -- If Pnam is present, it can be either inherited from an ancestor
1340 -- type (in which case it is legal to redefine it for this type), or
1341 -- be a previous definition of the attribute for the same type (in
1342 -- which case it is illegal).
1344 -- In the first case, it will have been analyzed already, and we
1345 -- can check that its profile does not match the expected profile
1346 -- for a stream attribute of U_Ent. In the second case, either Pnam
1347 -- has been analyzed (and has the expected profile), or it has not
1348 -- been analyzed yet (case of a type that has not been frozen yet
1349 -- and for which the stream attribute has been set using Set_TSS).
1352 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1354 Error_Msg_Sloc := Sloc (Pnam);
1355 Error_Msg_Name_1 := Attr;
1356 Error_Msg_N ("% attribute already defined #", Nam);
1362 if Is_Entity_Name (Expr) then
1363 if not Is_Overloaded (Expr) then
1364 if Has_Good_Profile (Entity (Expr)) then
1365 Subp := Entity (Expr);
1369 Get_First_Interp (Expr, I, It);
1370 while Present (It.Nam) loop
1371 if Has_Good_Profile (It.Nam) then
1376 Get_Next_Interp (I, It);
1381 if Present (Subp) then
1382 if Is_Abstract_Subprogram (Subp) then
1383 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1387 Set_Entity (Expr, Subp);
1388 Set_Etype (Expr, Etype (Subp));
1390 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1393 Error_Msg_Name_1 := Attr;
1394 Error_Msg_N ("incorrect expression for% attribute", Expr);
1396 end Analyze_Stream_TSS_Definition;
1398 ----------------------
1399 -- Duplicate_Clause --
1400 ----------------------
1402 function Duplicate_Clause return Boolean is
1406 -- Nothing to do if this attribute definition clause comes from
1407 -- an aspect specification, since we could not be duplicating an
1408 -- explicit clause, and we dealt with the case of duplicated aspects
1409 -- in Analyze_Aspect_Specifications.
1411 if From_Aspect_Specification (N) then
1415 -- Otherwise current clause may duplicate previous clause or a
1416 -- previously given aspect specification for the same aspect.
1418 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
1421 if Entity (A) = U_Ent then
1422 Error_Msg_Name_1 := Chars (N);
1423 Error_Msg_Sloc := Sloc (A);
1424 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
1430 end Duplicate_Clause;
1432 -- Start of processing for Analyze_Attribute_Definition_Clause
1435 -- Process Ignore_Rep_Clauses option
1437 if Ignore_Rep_Clauses then
1440 -- The following should be ignored. They do not affect legality
1441 -- and may be target dependent. The basic idea of -gnatI is to
1442 -- ignore any rep clauses that may be target dependent but do not
1443 -- affect legality (except possibly to be rejected because they
1444 -- are incompatible with the compilation target).
1446 when Attribute_Alignment |
1447 Attribute_Bit_Order |
1448 Attribute_Component_Size |
1449 Attribute_Machine_Radix |
1450 Attribute_Object_Size |
1453 Attribute_Stream_Size |
1454 Attribute_Value_Size =>
1456 Rewrite (N, Make_Null_Statement (Sloc (N)));
1459 -- The following should not be ignored, because in the first place
1460 -- they are reasonably portable, and should not cause problems in
1461 -- compiling code from another target, and also they do affect
1462 -- legality, e.g. failing to provide a stream attribute for a
1463 -- type may make a program illegal.
1465 when Attribute_External_Tag |
1469 Attribute_Storage_Pool |
1470 Attribute_Storage_Size |
1474 -- Other cases are errors ("attribute& cannot be set with
1475 -- definition clause"), which will be caught below.
1483 Ent := Entity (Nam);
1485 if Rep_Item_Too_Early (Ent, N) then
1489 -- Rep clause applies to full view of incomplete type or private type if
1490 -- we have one (if not, this is a premature use of the type). However,
1491 -- certain semantic checks need to be done on the specified entity (i.e.
1492 -- the private view), so we save it in Ent.
1494 if Is_Private_Type (Ent)
1495 and then Is_Derived_Type (Ent)
1496 and then not Is_Tagged_Type (Ent)
1497 and then No (Full_View (Ent))
1499 -- If this is a private type whose completion is a derivation from
1500 -- another private type, there is no full view, and the attribute
1501 -- belongs to the type itself, not its underlying parent.
1505 elsif Ekind (Ent) = E_Incomplete_Type then
1507 -- The attribute applies to the full view, set the entity of the
1508 -- attribute definition accordingly.
1510 Ent := Underlying_Type (Ent);
1512 Set_Entity (Nam, Ent);
1515 U_Ent := Underlying_Type (Ent);
1518 -- Complete other routine error checks
1520 if Etype (Nam) = Any_Type then
1523 elsif Scope (Ent) /= Current_Scope then
1524 Error_Msg_N ("entity must be declared in this scope", Nam);
1527 elsif No (U_Ent) then
1530 elsif Is_Type (U_Ent)
1531 and then not Is_First_Subtype (U_Ent)
1532 and then Id /= Attribute_Object_Size
1533 and then Id /= Attribute_Value_Size
1534 and then not From_At_Mod (N)
1536 Error_Msg_N ("cannot specify attribute for subtype", Nam);
1540 Set_Entity (N, U_Ent);
1542 -- Switch on particular attribute
1550 -- Address attribute definition clause
1552 when Attribute_Address => Address : begin
1554 -- A little error check, catch for X'Address use X'Address;
1556 if Nkind (Nam) = N_Identifier
1557 and then Nkind (Expr) = N_Attribute_Reference
1558 and then Attribute_Name (Expr) = Name_Address
1559 and then Nkind (Prefix (Expr)) = N_Identifier
1560 and then Chars (Nam) = Chars (Prefix (Expr))
1563 ("address for & is self-referencing", Prefix (Expr), Ent);
1567 -- Not that special case, carry on with analysis of expression
1569 Analyze_And_Resolve (Expr, RTE (RE_Address));
1571 -- Even when ignoring rep clauses we need to indicate that the
1572 -- entity has an address clause and thus it is legal to declare
1575 if Ignore_Rep_Clauses then
1576 if Ekind_In (U_Ent, E_Variable, E_Constant) then
1577 Record_Rep_Item (U_Ent, N);
1583 if Duplicate_Clause then
1586 -- Case of address clause for subprogram
1588 elsif Is_Subprogram (U_Ent) then
1589 if Has_Homonym (U_Ent) then
1591 ("address clause cannot be given " &
1592 "for overloaded subprogram",
1597 -- For subprograms, all address clauses are permitted, and we
1598 -- mark the subprogram as having a deferred freeze so that Gigi
1599 -- will not elaborate it too soon.
1601 -- Above needs more comments, what is too soon about???
1603 Set_Has_Delayed_Freeze (U_Ent);
1605 -- Case of address clause for entry
1607 elsif Ekind (U_Ent) = E_Entry then
1608 if Nkind (Parent (N)) = N_Task_Body then
1610 ("entry address must be specified in task spec", Nam);
1614 -- For entries, we require a constant address
1616 Check_Constant_Address_Clause (Expr, U_Ent);
1618 -- Special checks for task types
1620 if Is_Task_Type (Scope (U_Ent))
1621 and then Comes_From_Source (Scope (U_Ent))
1624 ("?entry address declared for entry in task type", N);
1626 ("\?only one task can be declared of this type", N);
1629 -- Entry address clauses are obsolescent
1631 Check_Restriction (No_Obsolescent_Features, N);
1633 if Warn_On_Obsolescent_Feature then
1635 ("attaching interrupt to task entry is an " &
1636 "obsolescent feature (RM J.7.1)?", N);
1638 ("\use interrupt procedure instead?", N);
1641 -- Case of an address clause for a controlled object which we
1642 -- consider to be erroneous.
1644 elsif Is_Controlled (Etype (U_Ent))
1645 or else Has_Controlled_Component (Etype (U_Ent))
1648 ("?controlled object& must not be overlaid", Nam, U_Ent);
1650 ("\?Program_Error will be raised at run time", Nam);
1651 Insert_Action (Declaration_Node (U_Ent),
1652 Make_Raise_Program_Error (Loc,
1653 Reason => PE_Overlaid_Controlled_Object));
1656 -- Case of address clause for a (non-controlled) object
1659 Ekind (U_Ent) = E_Variable
1661 Ekind (U_Ent) = E_Constant
1664 Expr : constant Node_Id := Expression (N);
1669 -- Exported variables cannot have an address clause, because
1670 -- this cancels the effect of the pragma Export.
1672 if Is_Exported (U_Ent) then
1674 ("cannot export object with address clause", Nam);
1678 Find_Overlaid_Entity (N, O_Ent, Off);
1680 -- Overlaying controlled objects is erroneous
1683 and then (Has_Controlled_Component (Etype (O_Ent))
1684 or else Is_Controlled (Etype (O_Ent)))
1687 ("?cannot overlay with controlled object", Expr);
1689 ("\?Program_Error will be raised at run time", Expr);
1690 Insert_Action (Declaration_Node (U_Ent),
1691 Make_Raise_Program_Error (Loc,
1692 Reason => PE_Overlaid_Controlled_Object));
1695 elsif Present (O_Ent)
1696 and then Ekind (U_Ent) = E_Constant
1697 and then not Is_Constant_Object (O_Ent)
1699 Error_Msg_N ("constant overlays a variable?", Expr);
1701 elsif Present (Renamed_Object (U_Ent)) then
1703 ("address clause not allowed"
1704 & " for a renaming declaration (RM 13.1(6))", Nam);
1707 -- Imported variables can have an address clause, but then
1708 -- the import is pretty meaningless except to suppress
1709 -- initializations, so we do not need such variables to
1710 -- be statically allocated (and in fact it causes trouble
1711 -- if the address clause is a local value).
1713 elsif Is_Imported (U_Ent) then
1714 Set_Is_Statically_Allocated (U_Ent, False);
1717 -- We mark a possible modification of a variable with an
1718 -- address clause, since it is likely aliasing is occurring.
1720 Note_Possible_Modification (Nam, Sure => False);
1722 -- Here we are checking for explicit overlap of one variable
1723 -- by another, and if we find this then mark the overlapped
1724 -- variable as also being volatile to prevent unwanted
1725 -- optimizations. This is a significant pessimization so
1726 -- avoid it when there is an offset, i.e. when the object
1727 -- is composite; they cannot be optimized easily anyway.
1730 and then Is_Object (O_Ent)
1733 Set_Treat_As_Volatile (O_Ent);
1736 -- Legality checks on the address clause for initialized
1737 -- objects is deferred until the freeze point, because
1738 -- a subsequent pragma might indicate that the object is
1739 -- imported and thus not initialized.
1741 Set_Has_Delayed_Freeze (U_Ent);
1743 -- If an initialization call has been generated for this
1744 -- object, it needs to be deferred to after the freeze node
1745 -- we have just now added, otherwise GIGI will see a
1746 -- reference to the variable (as actual to the IP call)
1747 -- before its definition.
1750 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
1752 if Present (Init_Call) then
1754 Append_Freeze_Action (U_Ent, Init_Call);
1758 if Is_Exported (U_Ent) then
1760 ("& cannot be exported if an address clause is given",
1763 ("\define and export a variable " &
1764 "that holds its address instead",
1768 -- Entity has delayed freeze, so we will generate an
1769 -- alignment check at the freeze point unless suppressed.
1771 if not Range_Checks_Suppressed (U_Ent)
1772 and then not Alignment_Checks_Suppressed (U_Ent)
1774 Set_Check_Address_Alignment (N);
1777 -- Kill the size check code, since we are not allocating
1778 -- the variable, it is somewhere else.
1780 Kill_Size_Check_Code (U_Ent);
1782 -- If the address clause is of the form:
1784 -- for Y'Address use X'Address
1788 -- Const : constant Address := X'Address;
1790 -- for Y'Address use Const;
1792 -- then we make an entry in the table for checking the size
1793 -- and alignment of the overlaying variable. We defer this
1794 -- check till after code generation to take full advantage
1795 -- of the annotation done by the back end. This entry is
1796 -- only made if the address clause comes from source.
1797 -- If the entity has a generic type, the check will be
1798 -- performed in the instance if the actual type justifies
1799 -- it, and we do not insert the clause in the table to
1800 -- prevent spurious warnings.
1802 if Address_Clause_Overlay_Warnings
1803 and then Comes_From_Source (N)
1804 and then Present (O_Ent)
1805 and then Is_Object (O_Ent)
1807 if not Is_Generic_Type (Etype (U_Ent)) then
1808 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
1811 -- If variable overlays a constant view, and we are
1812 -- warning on overlays, then mark the variable as
1813 -- overlaying a constant (we will give warnings later
1814 -- if this variable is assigned).
1816 if Is_Constant_Object (O_Ent)
1817 and then Ekind (U_Ent) = E_Variable
1819 Set_Overlays_Constant (U_Ent);
1824 -- Not a valid entity for an address clause
1827 Error_Msg_N ("address cannot be given for &", Nam);
1835 -- Alignment attribute definition clause
1837 when Attribute_Alignment => Alignment : declare
1838 Align : constant Uint := Get_Alignment_Value (Expr);
1843 if not Is_Type (U_Ent)
1844 and then Ekind (U_Ent) /= E_Variable
1845 and then Ekind (U_Ent) /= E_Constant
1847 Error_Msg_N ("alignment cannot be given for &", Nam);
1849 elsif Duplicate_Clause then
1852 elsif Align /= No_Uint then
1853 Set_Has_Alignment_Clause (U_Ent);
1854 Set_Alignment (U_Ent, Align);
1856 -- For an array type, U_Ent is the first subtype. In that case,
1857 -- also set the alignment of the anonymous base type so that
1858 -- other subtypes (such as the itypes for aggregates of the
1859 -- type) also receive the expected alignment.
1861 if Is_Array_Type (U_Ent) then
1862 Set_Alignment (Base_Type (U_Ent), Align);
1871 -- Bit_Order attribute definition clause
1873 when Attribute_Bit_Order => Bit_Order : declare
1875 if not Is_Record_Type (U_Ent) then
1877 ("Bit_Order can only be defined for record type", Nam);
1879 elsif Duplicate_Clause then
1883 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
1885 if Etype (Expr) = Any_Type then
1888 elsif not Is_Static_Expression (Expr) then
1889 Flag_Non_Static_Expr
1890 ("Bit_Order requires static expression!", Expr);
1893 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
1894 Set_Reverse_Bit_Order (U_Ent, True);
1900 --------------------
1901 -- Component_Size --
1902 --------------------
1904 -- Component_Size attribute definition clause
1906 when Attribute_Component_Size => Component_Size_Case : declare
1907 Csize : constant Uint := Static_Integer (Expr);
1911 New_Ctyp : Entity_Id;
1915 if not Is_Array_Type (U_Ent) then
1916 Error_Msg_N ("component size requires array type", Nam);
1920 Btype := Base_Type (U_Ent);
1921 Ctyp := Component_Type (Btype);
1923 if Duplicate_Clause then
1926 elsif Rep_Item_Too_Early (Btype, N) then
1929 elsif Csize /= No_Uint then
1930 Check_Size (Expr, Ctyp, Csize, Biased);
1932 -- For the biased case, build a declaration for a subtype that
1933 -- will be used to represent the biased subtype that reflects
1934 -- the biased representation of components. We need the subtype
1935 -- to get proper conversions on referencing elements of the
1936 -- array. Note: component size clauses are ignored in VM mode.
1938 if VM_Target = No_VM then
1941 Make_Defining_Identifier (Loc,
1943 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
1946 Make_Subtype_Declaration (Loc,
1947 Defining_Identifier => New_Ctyp,
1948 Subtype_Indication =>
1949 New_Occurrence_Of (Component_Type (Btype), Loc));
1951 Set_Parent (Decl, N);
1952 Analyze (Decl, Suppress => All_Checks);
1954 Set_Has_Delayed_Freeze (New_Ctyp, False);
1955 Set_Esize (New_Ctyp, Csize);
1956 Set_RM_Size (New_Ctyp, Csize);
1957 Init_Alignment (New_Ctyp);
1958 Set_Is_Itype (New_Ctyp, True);
1959 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
1961 Set_Component_Type (Btype, New_Ctyp);
1962 Set_Biased (New_Ctyp, N, "component size clause");
1965 Set_Component_Size (Btype, Csize);
1967 -- For VM case, we ignore component size clauses
1970 -- Give a warning unless we are in GNAT mode, in which case
1971 -- the warning is suppressed since it is not useful.
1973 if not GNAT_Mode then
1975 ("?component size ignored in this configuration", N);
1979 -- Deal with warning on overridden size
1981 if Warn_On_Overridden_Size
1982 and then Has_Size_Clause (Ctyp)
1983 and then RM_Size (Ctyp) /= Csize
1986 ("?component size overrides size clause for&",
1990 Set_Has_Component_Size_Clause (Btype, True);
1991 Set_Has_Non_Standard_Rep (Btype, True);
1993 end Component_Size_Case;
1999 when Attribute_External_Tag => External_Tag :
2001 if not Is_Tagged_Type (U_Ent) then
2002 Error_Msg_N ("should be a tagged type", Nam);
2005 if Duplicate_Clause then
2009 Analyze_And_Resolve (Expr, Standard_String);
2011 if not Is_Static_Expression (Expr) then
2012 Flag_Non_Static_Expr
2013 ("static string required for tag name!", Nam);
2016 if VM_Target = No_VM then
2017 Set_Has_External_Tag_Rep_Clause (U_Ent);
2019 Error_Msg_Name_1 := Attr;
2021 ("% attribute unsupported in this configuration", Nam);
2024 if not Is_Library_Level_Entity (U_Ent) then
2026 ("?non-unique external tag supplied for &", N, U_Ent);
2028 ("?\same external tag applies to all subprogram calls", N);
2030 ("?\corresponding internal tag cannot be obtained", N);
2039 when Attribute_Input =>
2040 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2041 Set_Has_Specified_Stream_Input (Ent);
2047 -- Machine radix attribute definition clause
2049 when Attribute_Machine_Radix => Machine_Radix : declare
2050 Radix : constant Uint := Static_Integer (Expr);
2053 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2054 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2056 elsif Duplicate_Clause then
2059 elsif Radix /= No_Uint then
2060 Set_Has_Machine_Radix_Clause (U_Ent);
2061 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2065 elsif Radix = 10 then
2066 Set_Machine_Radix_10 (U_Ent);
2068 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2077 -- Object_Size attribute definition clause
2079 when Attribute_Object_Size => Object_Size : declare
2080 Size : constant Uint := Static_Integer (Expr);
2083 pragma Warnings (Off, Biased);
2086 if not Is_Type (U_Ent) then
2087 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2089 elsif Duplicate_Clause then
2093 Check_Size (Expr, U_Ent, Size, Biased);
2101 UI_Mod (Size, 64) /= 0
2104 ("Object_Size must be 8, 16, 32, or multiple of 64",
2108 Set_Esize (U_Ent, Size);
2109 Set_Has_Object_Size_Clause (U_Ent);
2110 Alignment_Check_For_Esize_Change (U_Ent);
2118 when Attribute_Output =>
2119 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2120 Set_Has_Specified_Stream_Output (Ent);
2126 when Attribute_Read =>
2127 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2128 Set_Has_Specified_Stream_Read (Ent);
2134 -- Size attribute definition clause
2136 when Attribute_Size => Size : declare
2137 Size : constant Uint := Static_Integer (Expr);
2144 if Duplicate_Clause then
2147 elsif not Is_Type (U_Ent)
2148 and then Ekind (U_Ent) /= E_Variable
2149 and then Ekind (U_Ent) /= E_Constant
2151 Error_Msg_N ("size cannot be given for &", Nam);
2153 elsif Is_Array_Type (U_Ent)
2154 and then not Is_Constrained (U_Ent)
2157 ("size cannot be given for unconstrained array", Nam);
2159 elsif Size /= No_Uint then
2161 if VM_Target /= No_VM and then not GNAT_Mode then
2163 -- Size clause is not handled properly on VM targets.
2164 -- Display a warning unless we are in GNAT mode, in which
2165 -- case this is useless.
2168 ("?size clauses are ignored in this configuration", N);
2171 if Is_Type (U_Ent) then
2174 Etyp := Etype (U_Ent);
2177 -- Check size, note that Gigi is in charge of checking that the
2178 -- size of an array or record type is OK. Also we do not check
2179 -- the size in the ordinary fixed-point case, since it is too
2180 -- early to do so (there may be subsequent small clause that
2181 -- affects the size). We can check the size if a small clause
2182 -- has already been given.
2184 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2185 or else Has_Small_Clause (U_Ent)
2187 Check_Size (Expr, Etyp, Size, Biased);
2188 Set_Biased (U_Ent, N, "size clause", Biased);
2191 -- For types set RM_Size and Esize if possible
2193 if Is_Type (U_Ent) then
2194 Set_RM_Size (U_Ent, Size);
2196 -- For scalar types, increase Object_Size to power of 2, but
2197 -- not less than a storage unit in any case (i.e., normally
2198 -- this means it will be byte addressable).
2200 if Is_Scalar_Type (U_Ent) then
2201 if Size <= System_Storage_Unit then
2202 Init_Esize (U_Ent, System_Storage_Unit);
2203 elsif Size <= 16 then
2204 Init_Esize (U_Ent, 16);
2205 elsif Size <= 32 then
2206 Init_Esize (U_Ent, 32);
2208 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2211 -- For all other types, object size = value size. The
2212 -- backend will adjust as needed.
2215 Set_Esize (U_Ent, Size);
2218 Alignment_Check_For_Esize_Change (U_Ent);
2220 -- For objects, set Esize only
2223 if Is_Elementary_Type (Etyp) then
2224 if Size /= System_Storage_Unit
2226 Size /= System_Storage_Unit * 2
2228 Size /= System_Storage_Unit * 4
2230 Size /= System_Storage_Unit * 8
2232 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2233 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2235 ("size for primitive object must be a power of 2"
2236 & " in the range ^-^", N);
2240 Set_Esize (U_Ent, Size);
2243 Set_Has_Size_Clause (U_Ent);
2251 -- Small attribute definition clause
2253 when Attribute_Small => Small : declare
2254 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2258 Analyze_And_Resolve (Expr, Any_Real);
2260 if Etype (Expr) = Any_Type then
2263 elsif not Is_Static_Expression (Expr) then
2264 Flag_Non_Static_Expr
2265 ("small requires static expression!", Expr);
2269 Small := Expr_Value_R (Expr);
2271 if Small <= Ureal_0 then
2272 Error_Msg_N ("small value must be greater than zero", Expr);
2278 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2280 ("small requires an ordinary fixed point type", Nam);
2282 elsif Has_Small_Clause (U_Ent) then
2283 Error_Msg_N ("small already given for &", Nam);
2285 elsif Small > Delta_Value (U_Ent) then
2287 ("small value must not be greater then delta value", Nam);
2290 Set_Small_Value (U_Ent, Small);
2291 Set_Small_Value (Implicit_Base, Small);
2292 Set_Has_Small_Clause (U_Ent);
2293 Set_Has_Small_Clause (Implicit_Base);
2294 Set_Has_Non_Standard_Rep (Implicit_Base);
2302 -- Storage_Pool attribute definition clause
2304 when Attribute_Storage_Pool => Storage_Pool : declare
2309 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2311 ("storage pool cannot be given for access-to-subprogram type",
2316 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2319 ("storage pool can only be given for access types", Nam);
2322 elsif Is_Derived_Type (U_Ent) then
2324 ("storage pool cannot be given for a derived access type",
2327 elsif Duplicate_Clause then
2330 elsif Present (Associated_Storage_Pool (U_Ent)) then
2331 Error_Msg_N ("storage pool already given for &", Nam);
2336 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
2338 if not Denotes_Variable (Expr) then
2339 Error_Msg_N ("storage pool must be a variable", Expr);
2343 if Nkind (Expr) = N_Type_Conversion then
2344 T := Etype (Expression (Expr));
2349 -- The Stack_Bounded_Pool is used internally for implementing
2350 -- access types with a Storage_Size. Since it only work
2351 -- properly when used on one specific type, we need to check
2352 -- that it is not hijacked improperly:
2353 -- type T is access Integer;
2354 -- for T'Storage_Size use n;
2355 -- type Q is access Float;
2356 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
2358 if RTE_Available (RE_Stack_Bounded_Pool)
2359 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
2361 Error_Msg_N ("non-shareable internal Pool", Expr);
2365 -- If the argument is a name that is not an entity name, then
2366 -- we construct a renaming operation to define an entity of
2367 -- type storage pool.
2369 if not Is_Entity_Name (Expr)
2370 and then Is_Object_Reference (Expr)
2372 Pool := Make_Temporary (Loc, 'P', Expr);
2375 Rnode : constant Node_Id :=
2376 Make_Object_Renaming_Declaration (Loc,
2377 Defining_Identifier => Pool,
2379 New_Occurrence_Of (Etype (Expr), Loc),
2383 Insert_Before (N, Rnode);
2385 Set_Associated_Storage_Pool (U_Ent, Pool);
2388 elsif Is_Entity_Name (Expr) then
2389 Pool := Entity (Expr);
2391 -- If pool is a renamed object, get original one. This can
2392 -- happen with an explicit renaming, and within instances.
2394 while Present (Renamed_Object (Pool))
2395 and then Is_Entity_Name (Renamed_Object (Pool))
2397 Pool := Entity (Renamed_Object (Pool));
2400 if Present (Renamed_Object (Pool))
2401 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
2402 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
2404 Pool := Entity (Expression (Renamed_Object (Pool)));
2407 Set_Associated_Storage_Pool (U_Ent, Pool);
2409 elsif Nkind (Expr) = N_Type_Conversion
2410 and then Is_Entity_Name (Expression (Expr))
2411 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
2413 Pool := Entity (Expression (Expr));
2414 Set_Associated_Storage_Pool (U_Ent, Pool);
2417 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
2426 -- Storage_Size attribute definition clause
2428 when Attribute_Storage_Size => Storage_Size : declare
2429 Btype : constant Entity_Id := Base_Type (U_Ent);
2433 if Is_Task_Type (U_Ent) then
2434 Check_Restriction (No_Obsolescent_Features, N);
2436 if Warn_On_Obsolescent_Feature then
2438 ("storage size clause for task is an " &
2439 "obsolescent feature (RM J.9)?", N);
2440 Error_Msg_N ("\use Storage_Size pragma instead?", N);
2446 if not Is_Access_Type (U_Ent)
2447 and then Ekind (U_Ent) /= E_Task_Type
2449 Error_Msg_N ("storage size cannot be given for &", Nam);
2451 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
2453 ("storage size cannot be given for a derived access type",
2456 elsif Duplicate_Clause then
2460 Analyze_And_Resolve (Expr, Any_Integer);
2462 if Is_Access_Type (U_Ent) then
2463 if Present (Associated_Storage_Pool (U_Ent)) then
2464 Error_Msg_N ("storage pool already given for &", Nam);
2468 if Is_OK_Static_Expression (Expr)
2469 and then Expr_Value (Expr) = 0
2471 Set_No_Pool_Assigned (Btype);
2474 else -- Is_Task_Type (U_Ent)
2475 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
2477 if Present (Sprag) then
2478 Error_Msg_Sloc := Sloc (Sprag);
2480 ("Storage_Size already specified#", Nam);
2485 Set_Has_Storage_Size_Clause (Btype);
2493 when Attribute_Stream_Size => Stream_Size : declare
2494 Size : constant Uint := Static_Integer (Expr);
2497 if Ada_Version <= Ada_95 then
2498 Check_Restriction (No_Implementation_Attributes, N);
2501 if Duplicate_Clause then
2504 elsif Is_Elementary_Type (U_Ent) then
2505 if Size /= System_Storage_Unit
2507 Size /= System_Storage_Unit * 2
2509 Size /= System_Storage_Unit * 4
2511 Size /= System_Storage_Unit * 8
2513 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2515 ("stream size for elementary type must be a"
2516 & " power of 2 and at least ^", N);
2518 elsif RM_Size (U_Ent) > Size then
2519 Error_Msg_Uint_1 := RM_Size (U_Ent);
2521 ("stream size for elementary type must be a"
2522 & " power of 2 and at least ^", N);
2525 Set_Has_Stream_Size_Clause (U_Ent);
2528 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
2536 -- Value_Size attribute definition clause
2538 when Attribute_Value_Size => Value_Size : declare
2539 Size : constant Uint := Static_Integer (Expr);
2543 if not Is_Type (U_Ent) then
2544 Error_Msg_N ("Value_Size cannot be given for &", Nam);
2546 elsif Duplicate_Clause then
2549 elsif Is_Array_Type (U_Ent)
2550 and then not Is_Constrained (U_Ent)
2553 ("Value_Size cannot be given for unconstrained array", Nam);
2556 if Is_Elementary_Type (U_Ent) then
2557 Check_Size (Expr, U_Ent, Size, Biased);
2558 Set_Biased (U_Ent, N, "value size clause", Biased);
2561 Set_RM_Size (U_Ent, Size);
2569 when Attribute_Write =>
2570 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
2571 Set_Has_Specified_Stream_Write (Ent);
2573 -- All other attributes cannot be set
2577 ("attribute& cannot be set with definition clause", N);
2580 -- The test for the type being frozen must be performed after
2581 -- any expression the clause has been analyzed since the expression
2582 -- itself might cause freezing that makes the clause illegal.
2584 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
2587 end Analyze_Attribute_Definition_Clause;
2589 ----------------------------
2590 -- Analyze_Code_Statement --
2591 ----------------------------
2593 procedure Analyze_Code_Statement (N : Node_Id) is
2594 HSS : constant Node_Id := Parent (N);
2595 SBody : constant Node_Id := Parent (HSS);
2596 Subp : constant Entity_Id := Current_Scope;
2603 -- Analyze and check we get right type, note that this implements the
2604 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
2605 -- is the only way that Asm_Insn could possibly be visible.
2607 Analyze_And_Resolve (Expression (N));
2609 if Etype (Expression (N)) = Any_Type then
2611 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
2612 Error_Msg_N ("incorrect type for code statement", N);
2616 Check_Code_Statement (N);
2618 -- Make sure we appear in the handled statement sequence of a
2619 -- subprogram (RM 13.8(3)).
2621 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
2622 or else Nkind (SBody) /= N_Subprogram_Body
2625 ("code statement can only appear in body of subprogram", N);
2629 -- Do remaining checks (RM 13.8(3)) if not already done
2631 if not Is_Machine_Code_Subprogram (Subp) then
2632 Set_Is_Machine_Code_Subprogram (Subp);
2634 -- No exception handlers allowed
2636 if Present (Exception_Handlers (HSS)) then
2638 ("exception handlers not permitted in machine code subprogram",
2639 First (Exception_Handlers (HSS)));
2642 -- No declarations other than use clauses and pragmas (we allow
2643 -- certain internally generated declarations as well).
2645 Decl := First (Declarations (SBody));
2646 while Present (Decl) loop
2647 DeclO := Original_Node (Decl);
2648 if Comes_From_Source (DeclO)
2649 and not Nkind_In (DeclO, N_Pragma,
2650 N_Use_Package_Clause,
2652 N_Implicit_Label_Declaration)
2655 ("this declaration not allowed in machine code subprogram",
2662 -- No statements other than code statements, pragmas, and labels.
2663 -- Again we allow certain internally generated statements.
2665 Stmt := First (Statements (HSS));
2666 while Present (Stmt) loop
2667 StmtO := Original_Node (Stmt);
2668 if Comes_From_Source (StmtO)
2669 and then not Nkind_In (StmtO, N_Pragma,
2674 ("this statement is not allowed in machine code subprogram",
2681 end Analyze_Code_Statement;
2683 -----------------------------------------------
2684 -- Analyze_Enumeration_Representation_Clause --
2685 -----------------------------------------------
2687 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
2688 Ident : constant Node_Id := Identifier (N);
2689 Aggr : constant Node_Id := Array_Aggregate (N);
2690 Enumtype : Entity_Id;
2696 Err : Boolean := False;
2698 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
2699 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
2700 -- Allowed range of universal integer (= allowed range of enum lit vals)
2704 -- Minimum and maximum values of entries
2707 -- Pointer to node for literal providing max value
2710 if Ignore_Rep_Clauses then
2714 -- First some basic error checks
2717 Enumtype := Entity (Ident);
2719 if Enumtype = Any_Type
2720 or else Rep_Item_Too_Early (Enumtype, N)
2724 Enumtype := Underlying_Type (Enumtype);
2727 if not Is_Enumeration_Type (Enumtype) then
2729 ("enumeration type required, found}",
2730 Ident, First_Subtype (Enumtype));
2734 -- Ignore rep clause on generic actual type. This will already have
2735 -- been flagged on the template as an error, and this is the safest
2736 -- way to ensure we don't get a junk cascaded message in the instance.
2738 if Is_Generic_Actual_Type (Enumtype) then
2741 -- Type must be in current scope
2743 elsif Scope (Enumtype) /= Current_Scope then
2744 Error_Msg_N ("type must be declared in this scope", Ident);
2747 -- Type must be a first subtype
2749 elsif not Is_First_Subtype (Enumtype) then
2750 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
2753 -- Ignore duplicate rep clause
2755 elsif Has_Enumeration_Rep_Clause (Enumtype) then
2756 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
2759 -- Don't allow rep clause for standard [wide_[wide_]]character
2761 elsif Is_Standard_Character_Type (Enumtype) then
2762 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
2765 -- Check that the expression is a proper aggregate (no parentheses)
2767 elsif Paren_Count (Aggr) /= 0 then
2769 ("extra parentheses surrounding aggregate not allowed",
2773 -- All tests passed, so set rep clause in place
2776 Set_Has_Enumeration_Rep_Clause (Enumtype);
2777 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
2780 -- Now we process the aggregate. Note that we don't use the normal
2781 -- aggregate code for this purpose, because we don't want any of the
2782 -- normal expansion activities, and a number of special semantic
2783 -- rules apply (including the component type being any integer type)
2785 Elit := First_Literal (Enumtype);
2787 -- First the positional entries if any
2789 if Present (Expressions (Aggr)) then
2790 Expr := First (Expressions (Aggr));
2791 while Present (Expr) loop
2793 Error_Msg_N ("too many entries in aggregate", Expr);
2797 Val := Static_Integer (Expr);
2799 -- Err signals that we found some incorrect entries processing
2800 -- the list. The final checks for completeness and ordering are
2801 -- skipped in this case.
2803 if Val = No_Uint then
2805 elsif Val < Lo or else Hi < Val then
2806 Error_Msg_N ("value outside permitted range", Expr);
2810 Set_Enumeration_Rep (Elit, Val);
2811 Set_Enumeration_Rep_Expr (Elit, Expr);
2817 -- Now process the named entries if present
2819 if Present (Component_Associations (Aggr)) then
2820 Assoc := First (Component_Associations (Aggr));
2821 while Present (Assoc) loop
2822 Choice := First (Choices (Assoc));
2824 if Present (Next (Choice)) then
2826 ("multiple choice not allowed here", Next (Choice));
2830 if Nkind (Choice) = N_Others_Choice then
2831 Error_Msg_N ("others choice not allowed here", Choice);
2834 elsif Nkind (Choice) = N_Range then
2835 -- ??? should allow zero/one element range here
2836 Error_Msg_N ("range not allowed here", Choice);
2840 Analyze_And_Resolve (Choice, Enumtype);
2842 if Is_Entity_Name (Choice)
2843 and then Is_Type (Entity (Choice))
2845 Error_Msg_N ("subtype name not allowed here", Choice);
2847 -- ??? should allow static subtype with zero/one entry
2849 elsif Etype (Choice) = Base_Type (Enumtype) then
2850 if not Is_Static_Expression (Choice) then
2851 Flag_Non_Static_Expr
2852 ("non-static expression used for choice!", Choice);
2856 Elit := Expr_Value_E (Choice);
2858 if Present (Enumeration_Rep_Expr (Elit)) then
2859 Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit));
2861 ("representation for& previously given#",
2866 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
2868 Expr := Expression (Assoc);
2869 Val := Static_Integer (Expr);
2871 if Val = No_Uint then
2874 elsif Val < Lo or else Hi < Val then
2875 Error_Msg_N ("value outside permitted range", Expr);
2879 Set_Enumeration_Rep (Elit, Val);
2888 -- Aggregate is fully processed. Now we check that a full set of
2889 -- representations was given, and that they are in range and in order.
2890 -- These checks are only done if no other errors occurred.
2896 Elit := First_Literal (Enumtype);
2897 while Present (Elit) loop
2898 if No (Enumeration_Rep_Expr (Elit)) then
2899 Error_Msg_NE ("missing representation for&!", N, Elit);
2902 Val := Enumeration_Rep (Elit);
2904 if Min = No_Uint then
2908 if Val /= No_Uint then
2909 if Max /= No_Uint and then Val <= Max then
2911 ("enumeration value for& not ordered!",
2912 Enumeration_Rep_Expr (Elit), Elit);
2915 Max_Node := Enumeration_Rep_Expr (Elit);
2919 -- If there is at least one literal whose representation is not
2920 -- equal to the Pos value, then note that this enumeration type
2921 -- has a non-standard representation.
2923 if Val /= Enumeration_Pos (Elit) then
2924 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
2931 -- Now set proper size information
2934 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
2937 if Has_Size_Clause (Enumtype) then
2939 -- All OK, if size is OK now
2941 if RM_Size (Enumtype) >= Minsize then
2945 -- Try if we can get by with biasing
2948 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
2950 -- Error message if even biasing does not work
2952 if RM_Size (Enumtype) < Minsize then
2953 Error_Msg_Uint_1 := RM_Size (Enumtype);
2954 Error_Msg_Uint_2 := Max;
2956 ("previously given size (^) is too small "
2957 & "for this value (^)", Max_Node);
2959 -- If biasing worked, indicate that we now have biased rep
2963 (Enumtype, Size_Clause (Enumtype), "size clause");
2968 Set_RM_Size (Enumtype, Minsize);
2969 Set_Enum_Esize (Enumtype);
2972 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
2973 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
2974 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
2978 -- We repeat the too late test in case it froze itself!
2980 if Rep_Item_Too_Late (Enumtype, N) then
2983 end Analyze_Enumeration_Representation_Clause;
2985 ----------------------------
2986 -- Analyze_Free_Statement --
2987 ----------------------------
2989 procedure Analyze_Free_Statement (N : Node_Id) is
2991 Analyze (Expression (N));
2992 end Analyze_Free_Statement;
2994 ---------------------------
2995 -- Analyze_Freeze_Entity --
2996 ---------------------------
2998 procedure Analyze_Freeze_Entity (N : Node_Id) is
2999 E : constant Entity_Id := Entity (N);
3002 -- Remember that we are processing a freezing entity. Required to
3003 -- ensure correct decoration of internal entities associated with
3004 -- interfaces (see New_Overloaded_Entity).
3006 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3008 -- For tagged types covering interfaces add internal entities that link
3009 -- the primitives of the interfaces with the primitives that cover them.
3010 -- Note: These entities were originally generated only when generating
3011 -- code because their main purpose was to provide support to initialize
3012 -- the secondary dispatch tables. They are now generated also when
3013 -- compiling with no code generation to provide ASIS the relationship
3014 -- between interface primitives and tagged type primitives. They are
3015 -- also used to locate primitives covering interfaces when processing
3016 -- generics (see Derive_Subprograms).
3018 if Ada_Version >= Ada_2005
3019 and then Ekind (E) = E_Record_Type
3020 and then Is_Tagged_Type (E)
3021 and then not Is_Interface (E)
3022 and then Has_Interfaces (E)
3024 -- This would be a good common place to call the routine that checks
3025 -- overriding of interface primitives (and thus factorize calls to
3026 -- Check_Abstract_Overriding located at different contexts in the
3027 -- compiler). However, this is not possible because it causes
3028 -- spurious errors in case of late overriding.
3030 Add_Internal_Interface_Entities (E);
3035 if Ekind (E) = E_Record_Type
3036 and then Is_CPP_Class (E)
3037 and then Is_Tagged_Type (E)
3038 and then Tagged_Type_Expansion
3039 and then Expander_Active
3041 if CPP_Num_Prims (E) = 0 then
3043 -- If the CPP type has user defined components then it must import
3044 -- primitives from C++. This is required because if the C++ class
3045 -- has no primitives then the C++ compiler does not added the _tag
3046 -- component to the type.
3048 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3050 if First_Entity (E) /= Last_Entity (E) then
3052 ("?'C'P'P type must import at least one primitive from C++",
3057 -- Check that all its primitives are abstract or imported from C++.
3058 -- Check also availability of the C++ constructor.
3061 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3063 Error_Reported : Boolean := False;
3067 Elmt := First_Elmt (Primitive_Operations (E));
3068 while Present (Elmt) loop
3069 Prim := Node (Elmt);
3071 if Comes_From_Source (Prim) then
3072 if Is_Abstract_Subprogram (Prim) then
3075 elsif not Is_Imported (Prim)
3076 or else Convention (Prim) /= Convention_CPP
3079 ("?primitives of 'C'P'P types must be imported from C++"
3080 & " or abstract", Prim);
3082 elsif not Has_Constructors
3083 and then not Error_Reported
3085 Error_Msg_Name_1 := Chars (E);
3087 ("?'C'P'P constructor required for type %", Prim);
3088 Error_Reported := True;
3097 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3099 -- If we have a type with predicates, build predicate function
3101 if Is_Type (E) and then Has_Predicates (E) then
3102 Build_Predicate_Function (E, N);
3104 end Analyze_Freeze_Entity;
3106 ------------------------------------------
3107 -- Analyze_Record_Representation_Clause --
3108 ------------------------------------------
3110 -- Note: we check as much as we can here, but we can't do any checks
3111 -- based on the position values (e.g. overlap checks) until freeze time
3112 -- because especially in Ada 2005 (machine scalar mode), the processing
3113 -- for non-standard bit order can substantially change the positions.
3114 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3115 -- for the remainder of this processing.
3117 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3118 Ident : constant Node_Id := Identifier (N);
3123 Hbit : Uint := Uint_0;
3127 Rectype : Entity_Id;
3129 CR_Pragma : Node_Id := Empty;
3130 -- Points to N_Pragma node if Complete_Representation pragma present
3133 if Ignore_Rep_Clauses then
3138 Rectype := Entity (Ident);
3140 if Rectype = Any_Type
3141 or else Rep_Item_Too_Early (Rectype, N)
3145 Rectype := Underlying_Type (Rectype);
3148 -- First some basic error checks
3150 if not Is_Record_Type (Rectype) then
3152 ("record type required, found}", Ident, First_Subtype (Rectype));
3155 elsif Scope (Rectype) /= Current_Scope then
3156 Error_Msg_N ("type must be declared in this scope", N);
3159 elsif not Is_First_Subtype (Rectype) then
3160 Error_Msg_N ("cannot give record rep clause for subtype", N);
3163 elsif Has_Record_Rep_Clause (Rectype) then
3164 Error_Msg_N ("duplicate record rep clause ignored", N);
3167 elsif Rep_Item_Too_Late (Rectype, N) then
3171 if Present (Mod_Clause (N)) then
3173 Loc : constant Source_Ptr := Sloc (N);
3174 M : constant Node_Id := Mod_Clause (N);
3175 P : constant List_Id := Pragmas_Before (M);
3179 pragma Warnings (Off, Mod_Val);
3182 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3184 if Warn_On_Obsolescent_Feature then
3186 ("mod clause is an obsolescent feature (RM J.8)?", N);
3188 ("\use alignment attribute definition clause instead?", N);
3195 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3196 -- the Mod clause into an alignment clause anyway, so that the
3197 -- back-end can compute and back-annotate properly the size and
3198 -- alignment of types that may include this record.
3200 -- This seems dubious, this destroys the source tree in a manner
3201 -- not detectable by ASIS ???
3203 if Operating_Mode = Check_Semantics
3207 Make_Attribute_Definition_Clause (Loc,
3208 Name => New_Reference_To (Base_Type (Rectype), Loc),
3209 Chars => Name_Alignment,
3210 Expression => Relocate_Node (Expression (M)));
3212 Set_From_At_Mod (AtM_Nod);
3213 Insert_After (N, AtM_Nod);
3214 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3215 Set_Mod_Clause (N, Empty);
3218 -- Get the alignment value to perform error checking
3220 Mod_Val := Get_Alignment_Value (Expression (M));
3225 -- For untagged types, clear any existing component clauses for the
3226 -- type. If the type is derived, this is what allows us to override
3227 -- a rep clause for the parent. For type extensions, the representation
3228 -- of the inherited components is inherited, so we want to keep previous
3229 -- component clauses for completeness.
3231 if not Is_Tagged_Type (Rectype) then
3232 Comp := First_Component_Or_Discriminant (Rectype);
3233 while Present (Comp) loop
3234 Set_Component_Clause (Comp, Empty);
3235 Next_Component_Or_Discriminant (Comp);
3239 -- All done if no component clauses
3241 CC := First (Component_Clauses (N));
3247 -- A representation like this applies to the base type
3249 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3250 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3251 Set_Has_Specified_Layout (Base_Type (Rectype));
3253 -- Process the component clauses
3255 while Present (CC) loop
3259 if Nkind (CC) = N_Pragma then
3262 -- The only pragma of interest is Complete_Representation
3264 if Pragma_Name (CC) = Name_Complete_Representation then
3268 -- Processing for real component clause
3271 Posit := Static_Integer (Position (CC));
3272 Fbit := Static_Integer (First_Bit (CC));
3273 Lbit := Static_Integer (Last_Bit (CC));
3276 and then Fbit /= No_Uint
3277 and then Lbit /= No_Uint
3281 ("position cannot be negative", Position (CC));
3285 ("first bit cannot be negative", First_Bit (CC));
3287 -- The Last_Bit specified in a component clause must not be
3288 -- less than the First_Bit minus one (RM-13.5.1(10)).
3290 elsif Lbit < Fbit - 1 then
3292 ("last bit cannot be less than first bit minus one",
3295 -- Values look OK, so find the corresponding record component
3296 -- Even though the syntax allows an attribute reference for
3297 -- implementation-defined components, GNAT does not allow the
3298 -- tag to get an explicit position.
3300 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
3301 if Attribute_Name (Component_Name (CC)) = Name_Tag then
3302 Error_Msg_N ("position of tag cannot be specified", CC);
3304 Error_Msg_N ("illegal component name", CC);
3308 Comp := First_Entity (Rectype);
3309 while Present (Comp) loop
3310 exit when Chars (Comp) = Chars (Component_Name (CC));
3316 -- Maybe component of base type that is absent from
3317 -- statically constrained first subtype.
3319 Comp := First_Entity (Base_Type (Rectype));
3320 while Present (Comp) loop
3321 exit when Chars (Comp) = Chars (Component_Name (CC));
3328 ("component clause is for non-existent field", CC);
3330 -- Ada 2012 (AI05-0026): Any name that denotes a
3331 -- discriminant of an object of an unchecked union type
3332 -- shall not occur within a record_representation_clause.
3334 -- The general restriction of using record rep clauses on
3335 -- Unchecked_Union types has now been lifted. Since it is
3336 -- possible to introduce a record rep clause which mentions
3337 -- the discriminant of an Unchecked_Union in non-Ada 2012
3338 -- code, this check is applied to all versions of the
3341 elsif Ekind (Comp) = E_Discriminant
3342 and then Is_Unchecked_Union (Rectype)
3345 ("cannot reference discriminant of Unchecked_Union",
3346 Component_Name (CC));
3348 elsif Present (Component_Clause (Comp)) then
3350 -- Diagnose duplicate rep clause, or check consistency
3351 -- if this is an inherited component. In a double fault,
3352 -- there may be a duplicate inconsistent clause for an
3353 -- inherited component.
3355 if Scope (Original_Record_Component (Comp)) = Rectype
3356 or else Parent (Component_Clause (Comp)) = N
3358 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
3359 Error_Msg_N ("component clause previously given#", CC);
3363 Rep1 : constant Node_Id := Component_Clause (Comp);
3365 if Intval (Position (Rep1)) /=
3366 Intval (Position (CC))
3367 or else Intval (First_Bit (Rep1)) /=
3368 Intval (First_Bit (CC))
3369 or else Intval (Last_Bit (Rep1)) /=
3370 Intval (Last_Bit (CC))
3372 Error_Msg_N ("component clause inconsistent "
3373 & "with representation of ancestor", CC);
3374 elsif Warn_On_Redundant_Constructs then
3375 Error_Msg_N ("?redundant component clause "
3376 & "for inherited component!", CC);
3381 -- Normal case where this is the first component clause we
3382 -- have seen for this entity, so set it up properly.
3385 -- Make reference for field in record rep clause and set
3386 -- appropriate entity field in the field identifier.
3389 (Comp, Component_Name (CC), Set_Ref => False);
3390 Set_Entity (Component_Name (CC), Comp);
3392 -- Update Fbit and Lbit to the actual bit number
3394 Fbit := Fbit + UI_From_Int (SSU) * Posit;
3395 Lbit := Lbit + UI_From_Int (SSU) * Posit;
3397 if Has_Size_Clause (Rectype)
3398 and then Esize (Rectype) <= Lbit
3401 ("bit number out of range of specified size",
3404 Set_Component_Clause (Comp, CC);
3405 Set_Component_Bit_Offset (Comp, Fbit);
3406 Set_Esize (Comp, 1 + (Lbit - Fbit));
3407 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
3408 Set_Normalized_Position (Comp, Fbit / SSU);
3410 if Warn_On_Overridden_Size
3411 and then Has_Size_Clause (Etype (Comp))
3412 and then RM_Size (Etype (Comp)) /= Esize (Comp)
3415 ("?component size overrides size clause for&",
3416 Component_Name (CC), Etype (Comp));
3419 -- This information is also set in the corresponding
3420 -- component of the base type, found by accessing the
3421 -- Original_Record_Component link if it is present.
3423 Ocomp := Original_Record_Component (Comp);
3430 (Component_Name (CC),
3436 (Comp, First_Node (CC), "component clause", Biased);
3438 if Present (Ocomp) then
3439 Set_Component_Clause (Ocomp, CC);
3440 Set_Component_Bit_Offset (Ocomp, Fbit);
3441 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
3442 Set_Normalized_Position (Ocomp, Fbit / SSU);
3443 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
3445 Set_Normalized_Position_Max
3446 (Ocomp, Normalized_Position (Ocomp));
3448 -- Note: we don't use Set_Biased here, because we
3449 -- already gave a warning above if needed, and we
3450 -- would get a duplicate for the same name here.
3452 Set_Has_Biased_Representation
3453 (Ocomp, Has_Biased_Representation (Comp));
3456 if Esize (Comp) < 0 then
3457 Error_Msg_N ("component size is negative", CC);
3468 -- Check missing components if Complete_Representation pragma appeared
3470 if Present (CR_Pragma) then
3471 Comp := First_Component_Or_Discriminant (Rectype);
3472 while Present (Comp) loop
3473 if No (Component_Clause (Comp)) then
3475 ("missing component clause for &", CR_Pragma, Comp);
3478 Next_Component_Or_Discriminant (Comp);
3481 -- If no Complete_Representation pragma, warn if missing components
3483 elsif Warn_On_Unrepped_Components then
3485 Num_Repped_Components : Nat := 0;
3486 Num_Unrepped_Components : Nat := 0;
3489 -- First count number of repped and unrepped components
3491 Comp := First_Component_Or_Discriminant (Rectype);
3492 while Present (Comp) loop
3493 if Present (Component_Clause (Comp)) then
3494 Num_Repped_Components := Num_Repped_Components + 1;
3496 Num_Unrepped_Components := Num_Unrepped_Components + 1;
3499 Next_Component_Or_Discriminant (Comp);
3502 -- We are only interested in the case where there is at least one
3503 -- unrepped component, and at least half the components have rep
3504 -- clauses. We figure that if less than half have them, then the
3505 -- partial rep clause is really intentional. If the component
3506 -- type has no underlying type set at this point (as for a generic
3507 -- formal type), we don't know enough to give a warning on the
3510 if Num_Unrepped_Components > 0
3511 and then Num_Unrepped_Components < Num_Repped_Components
3513 Comp := First_Component_Or_Discriminant (Rectype);
3514 while Present (Comp) loop
3515 if No (Component_Clause (Comp))
3516 and then Comes_From_Source (Comp)
3517 and then Present (Underlying_Type (Etype (Comp)))
3518 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
3519 or else Size_Known_At_Compile_Time
3520 (Underlying_Type (Etype (Comp))))
3521 and then not Has_Warnings_Off (Rectype)
3523 Error_Msg_Sloc := Sloc (Comp);
3525 ("?no component clause given for & declared #",
3529 Next_Component_Or_Discriminant (Comp);
3534 end Analyze_Record_Representation_Clause;
3536 -------------------------------
3537 -- Build_Invariant_Procedure --
3538 -------------------------------
3540 -- The procedure that is constructed here has the form
3542 -- procedure typInvariant (Ixxx : typ) is
3544 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3545 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3547 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
3549 -- end typInvariant;
3551 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
3552 Loc : constant Source_Ptr := Sloc (Typ);
3559 Visible_Decls : constant List_Id := Visible_Declarations (N);
3560 Private_Decls : constant List_Id := Private_Declarations (N);
3562 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
3563 -- Appends statements to Stmts for any invariants in the rep item chain
3564 -- of the given type. If Inherit is False, then we only process entries
3565 -- on the chain for the type Typ. If Inherit is True, then we ignore any
3566 -- Invariant aspects, but we process all Invariant'Class aspects, adding
3567 -- "inherited" to the exception message and generating an informational
3568 -- message about the inheritance of an invariant.
3570 Object_Name : constant Name_Id := New_Internal_Name ('I');
3571 -- Name for argument of invariant procedure
3573 Object_Entity : constant Node_Id :=
3574 Make_Defining_Identifier (Loc, Object_Name);
3575 -- The procedure declaration entity for the argument
3577 --------------------
3578 -- Add_Invariants --
3579 --------------------
3581 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
3591 procedure Replace_Type_Reference (N : Node_Id);
3592 -- Replace a single occurrence N of the subtype name with a reference
3593 -- to the formal of the predicate function. N can be an identifier
3594 -- referencing the subtype, or a selected component, representing an
3595 -- appropriately qualified occurrence of the subtype name.
3597 procedure Replace_Type_References is
3598 new Replace_Type_References_Generic (Replace_Type_Reference);
3599 -- Traverse an expression replacing all occurrences of the subtype
3600 -- name with appropriate references to the object that is the formal
3601 -- parameter of the predicate function. Note that we must ensure
3602 -- that the type and entity information is properly set in the
3603 -- replacement node, since we will do a Preanalyze call of this
3604 -- expression without proper visibility of the procedure argument.
3606 ----------------------------
3607 -- Replace_Type_Reference --
3608 ----------------------------
3610 procedure Replace_Type_Reference (N : Node_Id) is
3612 -- Invariant'Class, replace with T'Class (obj)
3614 if Class_Present (Ritem) then
3616 Make_Type_Conversion (Loc,
3618 Make_Attribute_Reference (Loc,
3619 Prefix => New_Occurrence_Of (T, Loc),
3620 Attribute_Name => Name_Class),
3621 Expression => Make_Identifier (Loc, Object_Name)));
3623 Set_Entity (Expression (N), Object_Entity);
3624 Set_Etype (Expression (N), Typ);
3626 -- Invariant, replace with obj
3629 Rewrite (N, Make_Identifier (Loc, Object_Name));
3630 Set_Entity (N, Object_Entity);
3633 end Replace_Type_Reference;
3635 -- Start of processing for Add_Invariants
3638 Ritem := First_Rep_Item (T);
3639 while Present (Ritem) loop
3640 if Nkind (Ritem) = N_Pragma
3641 and then Pragma_Name (Ritem) = Name_Invariant
3643 Arg1 := First (Pragma_Argument_Associations (Ritem));
3644 Arg2 := Next (Arg1);
3645 Arg3 := Next (Arg2);
3647 Arg1 := Get_Pragma_Arg (Arg1);
3648 Arg2 := Get_Pragma_Arg (Arg2);
3650 -- For Inherit case, ignore Invariant, process only Class case
3653 if not Class_Present (Ritem) then
3657 -- For Inherit false, process only item for right type
3660 if Entity (Arg1) /= Typ then
3666 Stmts := Empty_List;
3669 Exp := New_Copy_Tree (Arg2);
3672 -- We need to replace any occurrences of the name of the type
3673 -- with references to the object, converted to type'Class in
3674 -- the case of Invariant'Class aspects.
3676 Replace_Type_References (Exp, Chars (T));
3678 -- Now we need to preanalyze the expression to properly capture
3679 -- the visibility in the visible part. The expression will not
3680 -- be analyzed for real until the body is analyzed, but that is
3681 -- at the end of the private part and has the wrong visibility.
3683 Set_Parent (Exp, N);
3684 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
3686 -- Build first two arguments for Check pragma
3689 Make_Pragma_Argument_Association (Loc,
3690 Expression => Make_Identifier (Loc, Name_Invariant)),
3691 Make_Pragma_Argument_Association (Loc, Expression => Exp));
3693 -- Add message if present in Invariant pragma
3695 if Present (Arg3) then
3696 Str := Strval (Get_Pragma_Arg (Arg3));
3698 -- If inherited case, and message starts "failed invariant",
3699 -- change it to be "failed inherited invariant".
3702 String_To_Name_Buffer (Str);
3704 if Name_Buffer (1 .. 16) = "failed invariant" then
3705 Insert_Str_In_Name_Buffer ("inherited ", 8);
3706 Str := String_From_Name_Buffer;
3711 Make_Pragma_Argument_Association (Loc,
3712 Expression => Make_String_Literal (Loc, Str)));
3715 -- Add Check pragma to list of statements
3719 Pragma_Identifier =>
3720 Make_Identifier (Loc, Name_Check),
3721 Pragma_Argument_Associations => Assoc));
3723 -- If Inherited case and option enabled, output info msg. Note
3724 -- that we know this is a case of Invariant'Class.
3726 if Inherit and Opt.List_Inherited_Aspects then
3727 Error_Msg_Sloc := Sloc (Ritem);
3729 ("?info: & inherits `Invariant''Class` aspect from #",
3735 Next_Rep_Item (Ritem);
3739 -- Start of processing for Build_Invariant_Procedure
3745 Set_Etype (Object_Entity, Typ);
3747 -- Add invariants for the current type
3749 Add_Invariants (Typ, Inherit => False);
3751 -- Add invariants for parent types
3754 Current_Typ : Entity_Id;
3755 Parent_Typ : Entity_Id;
3760 Parent_Typ := Etype (Current_Typ);
3762 if Is_Private_Type (Parent_Typ)
3763 and then Present (Full_View (Base_Type (Parent_Typ)))
3765 Parent_Typ := Full_View (Base_Type (Parent_Typ));
3768 exit when Parent_Typ = Current_Typ;
3770 Current_Typ := Parent_Typ;
3771 Add_Invariants (Current_Typ, Inherit => True);
3775 -- Build the procedure if we generated at least one Check pragma
3777 if Stmts /= No_List then
3779 -- Build procedure declaration
3782 Make_Defining_Identifier (Loc,
3783 Chars => New_External_Name (Chars (Typ), "Invariant"));
3784 Set_Has_Invariants (SId);
3785 Set_Invariant_Procedure (Typ, SId);
3788 Make_Procedure_Specification (Loc,
3789 Defining_Unit_Name => SId,
3790 Parameter_Specifications => New_List (
3791 Make_Parameter_Specification (Loc,
3792 Defining_Identifier => Object_Entity,
3793 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3795 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
3797 -- Build procedure body
3800 Make_Defining_Identifier (Loc,
3801 Chars => New_External_Name (Chars (Typ), "Invariant"));
3804 Make_Procedure_Specification (Loc,
3805 Defining_Unit_Name => SId,
3806 Parameter_Specifications => New_List (
3807 Make_Parameter_Specification (Loc,
3808 Defining_Identifier =>
3809 Make_Defining_Identifier (Loc, Object_Name),
3810 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3813 Make_Subprogram_Body (Loc,
3814 Specification => Spec,
3815 Declarations => Empty_List,
3816 Handled_Statement_Sequence =>
3817 Make_Handled_Sequence_Of_Statements (Loc,
3818 Statements => Stmts));
3820 -- Insert procedure declaration and spec at the appropriate points.
3821 -- Skip this if there are no private declarations (that's an error
3822 -- that will be diagnosed elsewhere, and there is no point in having
3823 -- an invariant procedure set if the full declaration is missing).
3825 if Present (Private_Decls) then
3827 -- The spec goes at the end of visible declarations, but they have
3828 -- already been analyzed, so we need to explicitly do the analyze.
3830 Append_To (Visible_Decls, PDecl);
3833 -- The body goes at the end of the private declarations, which we
3834 -- have not analyzed yet, so we do not need to perform an explicit
3835 -- analyze call. We skip this if there are no private declarations
3836 -- (this is an error that will be caught elsewhere);
3838 Append_To (Private_Decls, PBody);
3841 end Build_Invariant_Procedure;
3843 ------------------------------
3844 -- Build_Predicate_Function --
3845 ------------------------------
3847 -- The procedure that is constructed here has the form
3849 -- function typPredicate (Ixxx : typ) return Boolean is
3852 -- exp1 and then exp2 and then ...
3853 -- and then typ1Predicate (typ1 (Ixxx))
3854 -- and then typ2Predicate (typ2 (Ixxx))
3856 -- end typPredicate;
3858 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
3859 -- this is the point at which these expressions get analyzed, providing the
3860 -- required delay, and typ1, typ2, are entities from which predicates are
3861 -- inherited. Note that we do NOT generate Check pragmas, that's because we
3862 -- use this function even if checks are off, e.g. for membership tests.
3864 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
3865 Loc : constant Source_Ptr := Sloc (Typ);
3872 -- This is the expression for the return statement in the function. It
3873 -- is build by connecting the component predicates with AND THEN.
3875 procedure Add_Call (T : Entity_Id);
3876 -- Includes a call to the predicate function for type T in Expr if T
3877 -- has predicates and Predicate_Function (T) is non-empty.
3879 procedure Add_Predicates;
3880 -- Appends expressions for any Predicate pragmas in the rep item chain
3881 -- Typ to Expr. Note that we look only at items for this exact entity.
3882 -- Inheritance of predicates for the parent type is done by calling the
3883 -- Predicate_Function of the parent type, using Add_Call above.
3885 Object_Name : constant Name_Id := New_Internal_Name ('I');
3886 -- Name for argument of Predicate procedure
3892 procedure Add_Call (T : Entity_Id) is
3896 if Present (T) and then Present (Predicate_Function (T)) then
3897 Set_Has_Predicates (Typ);
3899 -- Build the call to the predicate function of T
3903 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
3905 -- Add call to evolving expression, using AND THEN if needed
3912 Left_Opnd => Relocate_Node (Expr),
3916 -- Output info message on inheritance if required. Note we do not
3917 -- give this information for generic actual types, since it is
3918 -- unwelcome noise in that case in instantiations. We also
3919 -- generally suppress the message in instantiations, and also
3920 -- if it involves internal names.
3922 if Opt.List_Inherited_Aspects
3923 and then not Is_Generic_Actual_Type (Typ)
3924 and then Instantiation_Depth (Sloc (Typ)) = 0
3925 and then not Is_Internal_Name (Chars (T))
3926 and then not Is_Internal_Name (Chars (Typ))
3928 Error_Msg_Sloc := Sloc (Predicate_Function (T));
3929 Error_Msg_Node_2 := T;
3930 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
3935 --------------------
3936 -- Add_Predicates --
3937 --------------------
3939 procedure Add_Predicates is
3944 procedure Replace_Type_Reference (N : Node_Id);
3945 -- Replace a single occurrence N of the subtype name with a reference
3946 -- to the formal of the predicate function. N can be an identifier
3947 -- referencing the subtype, or a selected component, representing an
3948 -- appropriately qualified occurrence of the subtype name.
3950 procedure Replace_Type_References is
3951 new Replace_Type_References_Generic (Replace_Type_Reference);
3952 -- Traverse an expression changing every occurrence of an identifier
3953 -- whose name mathches the name of the subtype with a reference to
3954 -- the formal parameter of the predicate function.
3956 ----------------------------
3957 -- Replace_Type_Reference --
3958 ----------------------------
3960 procedure Replace_Type_Reference (N : Node_Id) is
3962 Rewrite (N, Make_Identifier (Loc, Object_Name));
3963 end Replace_Type_Reference;
3965 -- Start of processing for Add_Predicates
3968 Ritem := First_Rep_Item (Typ);
3969 while Present (Ritem) loop
3970 if Nkind (Ritem) = N_Pragma
3971 and then Pragma_Name (Ritem) = Name_Predicate
3973 Arg1 := First (Pragma_Argument_Associations (Ritem));
3974 Arg2 := Next (Arg1);
3976 Arg1 := Get_Pragma_Arg (Arg1);
3977 Arg2 := Get_Pragma_Arg (Arg2);
3979 -- See if this predicate pragma is for the current type
3981 if Entity (Arg1) = Typ then
3983 -- We have a match, this entry is for our subtype
3985 -- First We need to replace any occurrences of the name of
3986 -- the type with references to the object.
3988 Replace_Type_References (Arg2, Chars (Typ));
3990 -- OK, replacement complete, now we can add the expression
3993 Expr := Relocate_Node (Arg2);
3995 -- There already was a predicate, so add to it
4000 Left_Opnd => Relocate_Node (Expr),
4001 Right_Opnd => Relocate_Node (Arg2));
4006 Next_Rep_Item (Ritem);
4010 -- Start of processing for Build_Predicate_Function
4013 -- Initialize for construction of statement list
4017 -- Return if already built or if type does not have predicates
4019 if not Has_Predicates (Typ)
4020 or else Present (Predicate_Function (Typ))
4025 -- Add Predicates for the current type
4029 -- Add predicates for ancestor if present
4032 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4034 if Present (Atyp) then
4039 -- If we have predicates, build the function
4041 if Present (Expr) then
4043 -- Build function declaration
4045 pragma Assert (Has_Predicates (Typ));
4047 Make_Defining_Identifier (Loc,
4048 Chars => New_External_Name (Chars (Typ), "Predicate"));
4049 Set_Has_Predicates (SId);
4050 Set_Predicate_Function (Typ, SId);
4053 Make_Function_Specification (Loc,
4054 Defining_Unit_Name => SId,
4055 Parameter_Specifications => New_List (
4056 Make_Parameter_Specification (Loc,
4057 Defining_Identifier =>
4058 Make_Defining_Identifier (Loc, Object_Name),
4059 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4060 Result_Definition =>
4061 New_Occurrence_Of (Standard_Boolean, Loc));
4063 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4065 -- Build function body
4068 Make_Defining_Identifier (Loc,
4069 Chars => New_External_Name (Chars (Typ), "Predicate"));
4072 Make_Function_Specification (Loc,
4073 Defining_Unit_Name => SId,
4074 Parameter_Specifications => New_List (
4075 Make_Parameter_Specification (Loc,
4076 Defining_Identifier =>
4077 Make_Defining_Identifier (Loc, Object_Name),
4079 New_Occurrence_Of (Typ, Loc))),
4080 Result_Definition =>
4081 New_Occurrence_Of (Standard_Boolean, Loc));
4084 Make_Subprogram_Body (Loc,
4085 Specification => Spec,
4086 Declarations => Empty_List,
4087 Handled_Statement_Sequence =>
4088 Make_Handled_Sequence_Of_Statements (Loc,
4089 Statements => New_List (
4090 Make_Simple_Return_Statement (Loc,
4091 Expression => Expr))));
4093 -- Insert declaration before freeze node and body after
4095 Insert_Before_And_Analyze (N, FDecl);
4096 Insert_After_And_Analyze (N, FBody);
4098 -- Deal with static predicate case
4100 if Ekind_In (Typ, E_Enumeration_Subtype,
4101 E_Modular_Integer_Subtype,
4102 E_Signed_Integer_Subtype)
4103 and then Is_Static_Subtype (Typ)
4105 Build_Static_Predicate (Typ, Expr, Object_Name);
4108 end Build_Predicate_Function;
4110 ----------------------------
4111 -- Build_Static_Predicate --
4112 ----------------------------
4114 procedure Build_Static_Predicate
4119 Loc : constant Source_Ptr := Sloc (Expr);
4121 Non_Static : exception;
4122 -- Raised if something non-static is found
4124 Btyp : constant Entity_Id := Base_Type (Typ);
4126 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4127 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4128 -- Low bound and high bound value of base type of Typ
4130 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4131 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4132 -- Low bound and high bound values of static subtype Typ
4137 -- One entry in a Rlist value, a single REnt (range entry) value
4138 -- denotes one range from Lo to Hi. To represent a single value
4139 -- range Lo = Hi = value.
4141 type RList is array (Nat range <>) of REnt;
4142 -- A list of ranges. The ranges are sorted in increasing order,
4143 -- and are disjoint (there is a gap of at least one value between
4144 -- each range in the table). A value is in the set of ranges in
4145 -- Rlist if it lies within one of these ranges
4147 False_Range : constant RList :=
4148 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4149 -- An empty set of ranges represents a range list that can never be
4150 -- satisfied, since there are no ranges in which the value could lie,
4151 -- so it does not lie in any of them. False_Range is a canonical value
4152 -- for this empty set, but general processing should test for an Rlist
4153 -- with length zero (see Is_False predicate), since other null ranges
4154 -- may appear which must be treated as False.
4156 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4157 -- Range representing True, value must be in the base range
4159 function "and" (Left, Right : RList) return RList;
4160 -- And's together two range lists, returning a range list. This is
4161 -- a set intersection operation.
4163 function "or" (Left, Right : RList) return RList;
4164 -- Or's together two range lists, returning a range list. This is a
4165 -- set union operation.
4167 function "not" (Right : RList) return RList;
4168 -- Returns complement of a given range list, i.e. a range list
4169 -- representing all the values in TLo .. THi that are not in the
4170 -- input operand Right.
4172 function Build_Val (V : Uint) return Node_Id;
4173 -- Return an analyzed N_Identifier node referencing this value, suitable
4174 -- for use as an entry in the Static_Predicate list. This node is typed
4175 -- with the base type.
4177 function Build_Range (Lo, Hi : Uint) return Node_Id;
4178 -- Return an analyzed N_Range node referencing this range, suitable
4179 -- for use as an entry in the Static_Predicate list. This node is typed
4180 -- with the base type.
4182 function Get_RList (Exp : Node_Id) return RList;
4183 -- This is a recursive routine that converts the given expression into
4184 -- a list of ranges, suitable for use in building the static predicate.
4186 function Is_False (R : RList) return Boolean;
4187 pragma Inline (Is_False);
4188 -- Returns True if the given range list is empty, and thus represents
4189 -- a False list of ranges that can never be satsified.
4191 function Is_True (R : RList) return Boolean;
4192 -- Returns True if R trivially represents the True predicate by having
4193 -- a single range from BLo to BHi.
4195 function Is_Type_Ref (N : Node_Id) return Boolean;
4196 pragma Inline (Is_Type_Ref);
4197 -- Returns if True if N is a reference to the type for the predicate in
4198 -- the expression (i.e. if it is an identifier whose Chars field matches
4199 -- the Nam given in the call).
4201 function Lo_Val (N : Node_Id) return Uint;
4202 -- Given static expression or static range from a Static_Predicate list,
4203 -- gets expression value or low bound of range.
4205 function Hi_Val (N : Node_Id) return Uint;
4206 -- Given static expression or static range from a Static_Predicate list,
4207 -- gets expression value of high bound of range.
4209 function Membership_Entry (N : Node_Id) return RList;
4210 -- Given a single membership entry (range, value, or subtype), returns
4211 -- the corresponding range list. Raises Static_Error if not static.
4213 function Membership_Entries (N : Node_Id) return RList;
4214 -- Given an element on an alternatives list of a membership operation,
4215 -- returns the range list corresponding to this entry and all following
4216 -- entries (i.e. returns the "or" of this list of values).
4218 function Stat_Pred (Typ : Entity_Id) return RList;
4219 -- Given a type, if it has a static predicate, then return the predicate
4220 -- as a range list, otherwise raise Non_Static.
4226 function "and" (Left, Right : RList) return RList is
4228 -- First range of result
4230 SLeft : Nat := Left'First;
4231 -- Start of rest of left entries
4233 SRight : Nat := Right'First;
4234 -- Start of rest of right entries
4237 -- If either range is True, return the other
4239 if Is_True (Left) then
4241 elsif Is_True (Right) then
4245 -- If either range is False, return False
4247 if Is_False (Left) or else Is_False (Right) then
4251 -- Loop to remove entries at start that are disjoint, and thus
4252 -- just get discarded from the result entirely.
4255 -- If no operands left in either operand, result is false
4257 if SLeft > Left'Last or else SRight > Right'Last then
4260 -- Discard first left operand entry if disjoint with right
4262 elsif Left (SLeft).Hi < Right (SRight).Lo then
4265 -- Discard first right operand entry if disjoint with left
4267 elsif Right (SRight).Hi < Left (SLeft).Lo then
4268 SRight := SRight + 1;
4270 -- Otherwise we have an overlapping entry
4277 -- Now we have two non-null operands, and first entries overlap.
4278 -- The first entry in the result will be the overlapping part of
4279 -- these two entries.
4281 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
4282 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
4284 -- Now we can remove the entry that ended at a lower value, since
4285 -- its contribution is entirely contained in Fent.
4287 if Left (SLeft).Hi <= Right (SRight).Hi then
4290 SRight := SRight + 1;
4293 -- Compute result by concatenating this first entry with the "and"
4294 -- of the remaining parts of the left and right operands. Note that
4295 -- if either of these is empty, "and" will yield empty, so that we
4296 -- will end up with just Fent, which is what we want in that case.
4299 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
4306 function "not" (Right : RList) return RList is
4308 -- Return True if False range
4310 if Is_False (Right) then
4314 -- Return False if True range
4316 if Is_True (Right) then
4320 -- Here if not trivial case
4323 Result : RList (1 .. Right'Length + 1);
4324 -- May need one more entry for gap at beginning and end
4327 -- Number of entries stored in Result
4332 if Right (Right'First).Lo > TLo then
4334 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
4337 -- Gaps between ranges
4339 for J in Right'First .. Right'Last - 1 loop
4342 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
4347 if Right (Right'Last).Hi < THi then
4349 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
4352 return Result (1 .. Count);
4360 function "or" (Left, Right : RList) return RList is
4362 -- First range of result
4364 SLeft : Nat := Left'First;
4365 -- Start of rest of left entries
4367 SRight : Nat := Right'First;
4368 -- Start of rest of right entries
4371 -- If either range is True, return True
4373 if Is_True (Left) or else Is_True (Right) then
4377 -- If either range is False (empty), return the other
4379 if Is_False (Left) then
4381 elsif Is_False (Right) then
4385 -- Initialize result first entry from left or right operand
4386 -- depending on which starts with the lower range.
4388 if Left (SLeft).Lo < Right (SRight).Lo then
4389 FEnt := Left (SLeft);
4392 FEnt := Right (SRight);
4393 SRight := SRight + 1;
4396 -- This loop eats ranges from left and right operands that
4397 -- are contiguous with the first range we are gathering.
4400 -- Eat first entry in left operand if contiguous or
4401 -- overlapped by gathered first operand of result.
4403 if SLeft <= Left'Last
4404 and then Left (SLeft).Lo <= FEnt.Hi + 1
4406 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
4409 -- Eat first entry in right operand if contiguous or
4410 -- overlapped by gathered right operand of result.
4412 elsif SRight <= Right'Last
4413 and then Right (SRight).Lo <= FEnt.Hi + 1
4415 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
4416 SRight := SRight + 1;
4418 -- All done if no more entries to eat!
4425 -- Obtain result as the first entry we just computed, concatenated
4426 -- to the "or" of the remaining results (if one operand is empty,
4427 -- this will just concatenate with the other
4430 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
4437 function Build_Range (Lo, Hi : Uint) return Node_Id is
4441 return Build_Val (Hi);
4445 Low_Bound => Build_Val (Lo),
4446 High_Bound => Build_Val (Hi));
4447 Set_Etype (Result, Btyp);
4448 Set_Analyzed (Result);
4457 function Build_Val (V : Uint) return Node_Id is
4461 if Is_Enumeration_Type (Typ) then
4462 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
4464 Result := Make_Integer_Literal (Loc, V);
4467 Set_Etype (Result, Btyp);
4468 Set_Is_Static_Expression (Result);
4469 Set_Analyzed (Result);
4477 function Get_RList (Exp : Node_Id) return RList is
4482 -- Static expression can only be true or false
4484 if Is_OK_Static_Expression (Exp) then
4488 if Expr_Value (Exp) = 0 then
4495 -- Otherwise test node type
4503 when N_Op_And | N_And_Then =>
4504 return Get_RList (Left_Opnd (Exp))
4506 Get_RList (Right_Opnd (Exp));
4510 when N_Op_Or | N_Or_Else =>
4511 return Get_RList (Left_Opnd (Exp))
4513 Get_RList (Right_Opnd (Exp));
4518 return not Get_RList (Right_Opnd (Exp));
4520 -- Comparisons of type with static value
4522 when N_Op_Compare =>
4523 -- Type is left operand
4525 if Is_Type_Ref (Left_Opnd (Exp))
4526 and then Is_OK_Static_Expression (Right_Opnd (Exp))
4528 Val := Expr_Value (Right_Opnd (Exp));
4530 -- Typ is right operand
4532 elsif Is_Type_Ref (Right_Opnd (Exp))
4533 and then Is_OK_Static_Expression (Left_Opnd (Exp))
4535 Val := Expr_Value (Left_Opnd (Exp));
4537 -- Invert sense of comparison
4540 when N_Op_Gt => Op := N_Op_Lt;
4541 when N_Op_Lt => Op := N_Op_Gt;
4542 when N_Op_Ge => Op := N_Op_Le;
4543 when N_Op_Le => Op := N_Op_Ge;
4544 when others => null;
4547 -- Other cases are non-static
4553 -- Construct range according to comparison operation
4557 return RList'(1 => REnt'(Val, Val));
4560 return RList'(1 => REnt'(Val, BHi));
4563 return RList'(1 => REnt'(Val + 1, BHi));
4566 return RList'(1 => REnt'(BLo, Val));
4569 return RList'(1 => REnt'(BLo, Val - 1));
4572 return RList'(REnt'(BLo, Val - 1),
4573 REnt'(Val + 1, BHi));
4576 raise Program_Error;
4582 if not Is_Type_Ref (Left_Opnd (Exp)) then
4586 if Present (Right_Opnd (Exp)) then
4587 return Membership_Entry (Right_Opnd (Exp));
4589 return Membership_Entries (First (Alternatives (Exp)));
4592 -- Negative membership (NOT IN)
4595 if not Is_Type_Ref (Left_Opnd (Exp)) then
4599 if Present (Right_Opnd (Exp)) then
4600 return not Membership_Entry (Right_Opnd (Exp));
4602 return not Membership_Entries (First (Alternatives (Exp)));
4605 -- Function call, may be call to static predicate
4607 when N_Function_Call =>
4608 if Is_Entity_Name (Name (Exp)) then
4610 Ent : constant Entity_Id := Entity (Name (Exp));
4612 if Has_Predicates (Ent) then
4613 return Stat_Pred (Etype (First_Formal (Ent)));
4618 -- Other function call cases are non-static
4622 -- Qualified expression, dig out the expression
4624 when N_Qualified_Expression =>
4625 return Get_RList (Expression (Exp));
4630 return (Get_RList (Left_Opnd (Exp))
4631 and not Get_RList (Right_Opnd (Exp)))
4632 or (Get_RList (Right_Opnd (Exp))
4633 and not Get_RList (Left_Opnd (Exp)));
4635 -- Any other node type is non-static
4646 function Hi_Val (N : Node_Id) return Uint is
4648 if Is_Static_Expression (N) then
4649 return Expr_Value (N);
4651 pragma Assert (Nkind (N) = N_Range);
4652 return Expr_Value (High_Bound (N));
4660 function Is_False (R : RList) return Boolean is
4662 return R'Length = 0;
4669 function Is_True (R : RList) return Boolean is
4672 and then R (R'First).Lo = BLo
4673 and then R (R'First).Hi = BHi;
4680 function Is_Type_Ref (N : Node_Id) return Boolean is
4682 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
4689 function Lo_Val (N : Node_Id) return Uint is
4691 if Is_Static_Expression (N) then
4692 return Expr_Value (N);
4694 pragma Assert (Nkind (N) = N_Range);
4695 return Expr_Value (Low_Bound (N));
4699 ------------------------
4700 -- Membership_Entries --
4701 ------------------------
4703 function Membership_Entries (N : Node_Id) return RList is
4705 if No (Next (N)) then
4706 return Membership_Entry (N);
4708 return Membership_Entry (N) or Membership_Entries (Next (N));
4710 end Membership_Entries;
4712 ----------------------
4713 -- Membership_Entry --
4714 ----------------------
4716 function Membership_Entry (N : Node_Id) return RList is
4724 if Nkind (N) = N_Range then
4725 if not Is_Static_Expression (Low_Bound (N))
4727 not Is_Static_Expression (High_Bound (N))
4731 SLo := Expr_Value (Low_Bound (N));
4732 SHi := Expr_Value (High_Bound (N));
4733 return RList'(1 => REnt'(SLo, SHi));
4736 -- Static expression case
4738 elsif Is_Static_Expression (N) then
4739 Val := Expr_Value (N);
4740 return RList'(1 => REnt'(Val, Val));
4742 -- Identifier (other than static expression) case
4744 else pragma Assert (Nkind (N) = N_Identifier);
4748 if Is_Type (Entity (N)) then
4750 -- If type has predicates, process them
4752 if Has_Predicates (Entity (N)) then
4753 return Stat_Pred (Entity (N));
4755 -- For static subtype without predicates, get range
4757 elsif Is_Static_Subtype (Entity (N)) then
4758 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
4759 SHi := Expr_Value (Type_High_Bound (Entity (N)));
4760 return RList'(1 => REnt'(SLo, SHi));
4762 -- Any other type makes us non-static
4768 -- Any other kind of identifier in predicate (e.g. a non-static
4769 -- expression value) means this is not a static predicate.
4775 end Membership_Entry;
4781 function Stat_Pred (Typ : Entity_Id) return RList is
4783 -- Not static if type does not have static predicates
4785 if not Has_Predicates (Typ)
4786 or else No (Static_Predicate (Typ))
4791 -- Otherwise we convert the predicate list to a range list
4794 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
4798 P := First (Static_Predicate (Typ));
4799 for J in Result'Range loop
4800 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
4808 -- Start of processing for Build_Static_Predicate
4811 -- Now analyze the expression to see if it is a static predicate
4814 Ranges : constant RList := Get_RList (Expr);
4815 -- Range list from expression if it is static
4820 -- Convert range list into a form for the static predicate. In the
4821 -- Ranges array, we just have raw ranges, these must be converted
4822 -- to properly typed and analyzed static expressions or range nodes.
4824 -- Note: here we limit ranges to the ranges of the subtype, so that
4825 -- a predicate is always false for values outside the subtype. That
4826 -- seems fine, such values are invalid anyway, and considering them
4827 -- to fail the predicate seems allowed and friendly, and furthermore
4828 -- simplifies processing for case statements and loops.
4832 for J in Ranges'Range loop
4834 Lo : Uint := Ranges (J).Lo;
4835 Hi : Uint := Ranges (J).Hi;
4838 -- Ignore completely out of range entry
4840 if Hi < TLo or else Lo > THi then
4843 -- Otherwise process entry
4846 -- Adjust out of range value to subtype range
4856 -- Convert range into required form
4859 Append_To (Plist, Build_Val (Lo));
4861 Append_To (Plist, Build_Range (Lo, Hi));
4867 -- Processing was successful and all entries were static, so now we
4868 -- can store the result as the predicate list.
4870 Set_Static_Predicate (Typ, Plist);
4872 -- The processing for static predicates put the expression into
4873 -- canonical form as a series of ranges. It also eliminated
4874 -- duplicates and collapsed and combined ranges. We might as well
4875 -- replace the alternatives list of the right operand of the
4876 -- membership test with the static predicate list, which will
4877 -- usually be more efficient.
4880 New_Alts : constant List_Id := New_List;
4885 Old_Node := First (Plist);
4886 while Present (Old_Node) loop
4887 New_Node := New_Copy (Old_Node);
4889 if Nkind (New_Node) = N_Range then
4890 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
4891 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
4894 Append_To (New_Alts, New_Node);
4898 -- If empty list, replace by False
4900 if Is_Empty_List (New_Alts) then
4901 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
4903 -- Else replace by set membership test
4908 Left_Opnd => Make_Identifier (Loc, Nam),
4909 Right_Opnd => Empty,
4910 Alternatives => New_Alts));
4912 -- Resolve new expression in function context
4914 Install_Formals (Predicate_Function (Typ));
4915 Push_Scope (Predicate_Function (Typ));
4916 Analyze_And_Resolve (Expr, Standard_Boolean);
4922 -- If non-static, return doing nothing
4927 end Build_Static_Predicate;
4929 -----------------------------------
4930 -- Check_Constant_Address_Clause --
4931 -----------------------------------
4933 procedure Check_Constant_Address_Clause
4937 procedure Check_At_Constant_Address (Nod : Node_Id);
4938 -- Checks that the given node N represents a name whose 'Address is
4939 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
4940 -- address value is the same at the point of declaration of U_Ent and at
4941 -- the time of elaboration of the address clause.
4943 procedure Check_Expr_Constants (Nod : Node_Id);
4944 -- Checks that Nod meets the requirements for a constant address clause
4945 -- in the sense of the enclosing procedure.
4947 procedure Check_List_Constants (Lst : List_Id);
4948 -- Check that all elements of list Lst meet the requirements for a
4949 -- constant address clause in the sense of the enclosing procedure.
4951 -------------------------------
4952 -- Check_At_Constant_Address --
4953 -------------------------------
4955 procedure Check_At_Constant_Address (Nod : Node_Id) is
4957 if Is_Entity_Name (Nod) then
4958 if Present (Address_Clause (Entity ((Nod)))) then
4960 ("invalid address clause for initialized object &!",
4963 ("address for& cannot" &
4964 " depend on another address clause! (RM 13.1(22))!",
4967 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
4968 and then Sloc (U_Ent) < Sloc (Entity (Nod))
4971 ("invalid address clause for initialized object &!",
4973 Error_Msg_Node_2 := U_Ent;
4975 ("\& must be defined before & (RM 13.1(22))!",
4979 elsif Nkind (Nod) = N_Selected_Component then
4981 T : constant Entity_Id := Etype (Prefix (Nod));
4984 if (Is_Record_Type (T)
4985 and then Has_Discriminants (T))
4988 and then Is_Record_Type (Designated_Type (T))
4989 and then Has_Discriminants (Designated_Type (T)))
4992 ("invalid address clause for initialized object &!",
4995 ("\address cannot depend on component" &
4996 " of discriminated record (RM 13.1(22))!",
4999 Check_At_Constant_Address (Prefix (Nod));
5003 elsif Nkind (Nod) = N_Indexed_Component then
5004 Check_At_Constant_Address (Prefix (Nod));
5005 Check_List_Constants (Expressions (Nod));
5008 Check_Expr_Constants (Nod);
5010 end Check_At_Constant_Address;
5012 --------------------------
5013 -- Check_Expr_Constants --
5014 --------------------------
5016 procedure Check_Expr_Constants (Nod : Node_Id) is
5017 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
5018 Ent : Entity_Id := Empty;
5021 if Nkind (Nod) in N_Has_Etype
5022 and then Etype (Nod) = Any_Type
5028 when N_Empty | N_Error =>
5031 when N_Identifier | N_Expanded_Name =>
5032 Ent := Entity (Nod);
5034 -- We need to look at the original node if it is different
5035 -- from the node, since we may have rewritten things and
5036 -- substituted an identifier representing the rewrite.
5038 if Original_Node (Nod) /= Nod then
5039 Check_Expr_Constants (Original_Node (Nod));
5041 -- If the node is an object declaration without initial
5042 -- value, some code has been expanded, and the expression
5043 -- is not constant, even if the constituents might be
5044 -- acceptable, as in A'Address + offset.
5046 if Ekind (Ent) = E_Variable
5048 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
5050 No (Expression (Declaration_Node (Ent)))
5053 ("invalid address clause for initialized object &!",
5056 -- If entity is constant, it may be the result of expanding
5057 -- a check. We must verify that its declaration appears
5058 -- before the object in question, else we also reject the
5061 elsif Ekind (Ent) = E_Constant
5062 and then In_Same_Source_Unit (Ent, U_Ent)
5063 and then Sloc (Ent) > Loc_U_Ent
5066 ("invalid address clause for initialized object &!",
5073 -- Otherwise look at the identifier and see if it is OK
5075 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
5076 or else Is_Type (Ent)
5081 Ekind (Ent) = E_Constant
5083 Ekind (Ent) = E_In_Parameter
5085 -- This is the case where we must have Ent defined before
5086 -- U_Ent. Clearly if they are in different units this
5087 -- requirement is met since the unit containing Ent is
5088 -- already processed.
5090 if not In_Same_Source_Unit (Ent, U_Ent) then
5093 -- Otherwise location of Ent must be before the location
5094 -- of U_Ent, that's what prior defined means.
5096 elsif Sloc (Ent) < Loc_U_Ent then
5101 ("invalid address clause for initialized object &!",
5103 Error_Msg_Node_2 := U_Ent;
5105 ("\& must be defined before & (RM 13.1(22))!",
5109 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
5110 Check_Expr_Constants (Original_Node (Nod));
5114 ("invalid address clause for initialized object &!",
5117 if Comes_From_Source (Ent) then
5119 ("\reference to variable& not allowed"
5120 & " (RM 13.1(22))!", Nod, Ent);
5123 ("non-static expression not allowed"
5124 & " (RM 13.1(22))!", Nod);
5128 when N_Integer_Literal =>
5130 -- If this is a rewritten unchecked conversion, in a system
5131 -- where Address is an integer type, always use the base type
5132 -- for a literal value. This is user-friendly and prevents
5133 -- order-of-elaboration issues with instances of unchecked
5136 if Nkind (Original_Node (Nod)) = N_Function_Call then
5137 Set_Etype (Nod, Base_Type (Etype (Nod)));
5140 when N_Real_Literal |
5142 N_Character_Literal =>
5146 Check_Expr_Constants (Low_Bound (Nod));
5147 Check_Expr_Constants (High_Bound (Nod));
5149 when N_Explicit_Dereference =>
5150 Check_Expr_Constants (Prefix (Nod));
5152 when N_Indexed_Component =>
5153 Check_Expr_Constants (Prefix (Nod));
5154 Check_List_Constants (Expressions (Nod));
5157 Check_Expr_Constants (Prefix (Nod));
5158 Check_Expr_Constants (Discrete_Range (Nod));
5160 when N_Selected_Component =>
5161 Check_Expr_Constants (Prefix (Nod));
5163 when N_Attribute_Reference =>
5164 if Attribute_Name (Nod) = Name_Address
5166 Attribute_Name (Nod) = Name_Access
5168 Attribute_Name (Nod) = Name_Unchecked_Access
5170 Attribute_Name (Nod) = Name_Unrestricted_Access
5172 Check_At_Constant_Address (Prefix (Nod));
5175 Check_Expr_Constants (Prefix (Nod));
5176 Check_List_Constants (Expressions (Nod));
5180 Check_List_Constants (Component_Associations (Nod));
5181 Check_List_Constants (Expressions (Nod));
5183 when N_Component_Association =>
5184 Check_Expr_Constants (Expression (Nod));
5186 when N_Extension_Aggregate =>
5187 Check_Expr_Constants (Ancestor_Part (Nod));
5188 Check_List_Constants (Component_Associations (Nod));
5189 Check_List_Constants (Expressions (Nod));
5194 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
5195 Check_Expr_Constants (Left_Opnd (Nod));
5196 Check_Expr_Constants (Right_Opnd (Nod));
5199 Check_Expr_Constants (Right_Opnd (Nod));
5201 when N_Type_Conversion |
5202 N_Qualified_Expression |
5204 Check_Expr_Constants (Expression (Nod));
5206 when N_Unchecked_Type_Conversion =>
5207 Check_Expr_Constants (Expression (Nod));
5209 -- If this is a rewritten unchecked conversion, subtypes in
5210 -- this node are those created within the instance. To avoid
5211 -- order of elaboration issues, replace them with their base
5212 -- types. Note that address clauses can cause order of
5213 -- elaboration problems because they are elaborated by the
5214 -- back-end at the point of definition, and may mention
5215 -- entities declared in between (as long as everything is
5216 -- static). It is user-friendly to allow unchecked conversions
5219 if Nkind (Original_Node (Nod)) = N_Function_Call then
5220 Set_Etype (Expression (Nod),
5221 Base_Type (Etype (Expression (Nod))));
5222 Set_Etype (Nod, Base_Type (Etype (Nod)));
5225 when N_Function_Call =>
5226 if not Is_Pure (Entity (Name (Nod))) then
5228 ("invalid address clause for initialized object &!",
5232 ("\function & is not pure (RM 13.1(22))!",
5233 Nod, Entity (Name (Nod)));
5236 Check_List_Constants (Parameter_Associations (Nod));
5239 when N_Parameter_Association =>
5240 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
5244 ("invalid address clause for initialized object &!",
5247 ("\must be constant defined before& (RM 13.1(22))!",
5250 end Check_Expr_Constants;
5252 --------------------------
5253 -- Check_List_Constants --
5254 --------------------------
5256 procedure Check_List_Constants (Lst : List_Id) is
5260 if Present (Lst) then
5261 Nod1 := First (Lst);
5262 while Present (Nod1) loop
5263 Check_Expr_Constants (Nod1);
5267 end Check_List_Constants;
5269 -- Start of processing for Check_Constant_Address_Clause
5272 -- If rep_clauses are to be ignored, no need for legality checks. In
5273 -- particular, no need to pester user about rep clauses that violate
5274 -- the rule on constant addresses, given that these clauses will be
5275 -- removed by Freeze before they reach the back end.
5277 if not Ignore_Rep_Clauses then
5278 Check_Expr_Constants (Expr);
5280 end Check_Constant_Address_Clause;
5282 ----------------------------------------
5283 -- Check_Record_Representation_Clause --
5284 ----------------------------------------
5286 procedure Check_Record_Representation_Clause (N : Node_Id) is
5287 Loc : constant Source_Ptr := Sloc (N);
5288 Ident : constant Node_Id := Identifier (N);
5289 Rectype : Entity_Id;
5294 Hbit : Uint := Uint_0;
5298 Max_Bit_So_Far : Uint;
5299 -- Records the maximum bit position so far. If all field positions
5300 -- are monotonically increasing, then we can skip the circuit for
5301 -- checking for overlap, since no overlap is possible.
5303 Tagged_Parent : Entity_Id := Empty;
5304 -- This is set in the case of a derived tagged type for which we have
5305 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
5306 -- positioned by record representation clauses). In this case we must
5307 -- check for overlap between components of this tagged type, and the
5308 -- components of its parent. Tagged_Parent will point to this parent
5309 -- type. For all other cases Tagged_Parent is left set to Empty.
5311 Parent_Last_Bit : Uint;
5312 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
5313 -- last bit position for any field in the parent type. We only need to
5314 -- check overlap for fields starting below this point.
5316 Overlap_Check_Required : Boolean;
5317 -- Used to keep track of whether or not an overlap check is required
5319 Overlap_Detected : Boolean := False;
5320 -- Set True if an overlap is detected
5322 Ccount : Natural := 0;
5323 -- Number of component clauses in record rep clause
5325 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
5326 -- Given two entities for record components or discriminants, checks
5327 -- if they have overlapping component clauses and issues errors if so.
5329 procedure Find_Component;
5330 -- Finds component entity corresponding to current component clause (in
5331 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
5332 -- start/stop bits for the field. If there is no matching component or
5333 -- if the matching component does not have a component clause, then
5334 -- that's an error and Comp is set to Empty, but no error message is
5335 -- issued, since the message was already given. Comp is also set to
5336 -- Empty if the current "component clause" is in fact a pragma.
5338 -----------------------------
5339 -- Check_Component_Overlap --
5340 -----------------------------
5342 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
5343 CC1 : constant Node_Id := Component_Clause (C1_Ent);
5344 CC2 : constant Node_Id := Component_Clause (C2_Ent);
5347 if Present (CC1) and then Present (CC2) then
5349 -- Exclude odd case where we have two tag fields in the same
5350 -- record, both at location zero. This seems a bit strange, but
5351 -- it seems to happen in some circumstances, perhaps on an error.
5353 if Chars (C1_Ent) = Name_uTag
5355 Chars (C2_Ent) = Name_uTag
5360 -- Here we check if the two fields overlap
5363 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
5364 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
5365 E1 : constant Uint := S1 + Esize (C1_Ent);
5366 E2 : constant Uint := S2 + Esize (C2_Ent);
5369 if E2 <= S1 or else E1 <= S2 then
5372 Error_Msg_Node_2 := Component_Name (CC2);
5373 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
5374 Error_Msg_Node_1 := Component_Name (CC1);
5376 ("component& overlaps & #", Component_Name (CC1));
5377 Overlap_Detected := True;
5381 end Check_Component_Overlap;
5383 --------------------
5384 -- Find_Component --
5385 --------------------
5387 procedure Find_Component is
5389 procedure Search_Component (R : Entity_Id);
5390 -- Search components of R for a match. If found, Comp is set.
5392 ----------------------
5393 -- Search_Component --
5394 ----------------------
5396 procedure Search_Component (R : Entity_Id) is
5398 Comp := First_Component_Or_Discriminant (R);
5399 while Present (Comp) loop
5401 -- Ignore error of attribute name for component name (we
5402 -- already gave an error message for this, so no need to
5405 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
5408 exit when Chars (Comp) = Chars (Component_Name (CC));
5411 Next_Component_Or_Discriminant (Comp);
5413 end Search_Component;
5415 -- Start of processing for Find_Component
5418 -- Return with Comp set to Empty if we have a pragma
5420 if Nkind (CC) = N_Pragma then
5425 -- Search current record for matching component
5427 Search_Component (Rectype);
5429 -- If not found, maybe component of base type that is absent from
5430 -- statically constrained first subtype.
5433 Search_Component (Base_Type (Rectype));
5436 -- If no component, or the component does not reference the component
5437 -- clause in question, then there was some previous error for which
5438 -- we already gave a message, so just return with Comp Empty.
5441 or else Component_Clause (Comp) /= CC
5445 -- Normal case where we have a component clause
5448 Fbit := Component_Bit_Offset (Comp);
5449 Lbit := Fbit + Esize (Comp) - 1;
5453 -- Start of processing for Check_Record_Representation_Clause
5457 Rectype := Entity (Ident);
5459 if Rectype = Any_Type then
5462 Rectype := Underlying_Type (Rectype);
5465 -- See if we have a fully repped derived tagged type
5468 PS : constant Entity_Id := Parent_Subtype (Rectype);
5471 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
5472 Tagged_Parent := PS;
5474 -- Find maximum bit of any component of the parent type
5476 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
5477 Pcomp := First_Entity (Tagged_Parent);
5478 while Present (Pcomp) loop
5479 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
5480 if Component_Bit_Offset (Pcomp) /= No_Uint
5481 and then Known_Static_Esize (Pcomp)
5486 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
5489 Next_Entity (Pcomp);
5495 -- All done if no component clauses
5497 CC := First (Component_Clauses (N));
5503 -- If a tag is present, then create a component clause that places it
5504 -- at the start of the record (otherwise gigi may place it after other
5505 -- fields that have rep clauses).
5507 Fent := First_Entity (Rectype);
5509 if Nkind (Fent) = N_Defining_Identifier
5510 and then Chars (Fent) = Name_uTag
5512 Set_Component_Bit_Offset (Fent, Uint_0);
5513 Set_Normalized_Position (Fent, Uint_0);
5514 Set_Normalized_First_Bit (Fent, Uint_0);
5515 Set_Normalized_Position_Max (Fent, Uint_0);
5516 Init_Esize (Fent, System_Address_Size);
5518 Set_Component_Clause (Fent,
5519 Make_Component_Clause (Loc,
5520 Component_Name => Make_Identifier (Loc, Name_uTag),
5522 Position => Make_Integer_Literal (Loc, Uint_0),
5523 First_Bit => Make_Integer_Literal (Loc, Uint_0),
5525 Make_Integer_Literal (Loc,
5526 UI_From_Int (System_Address_Size))));
5528 Ccount := Ccount + 1;
5531 Max_Bit_So_Far := Uint_Minus_1;
5532 Overlap_Check_Required := False;
5534 -- Process the component clauses
5536 while Present (CC) loop
5539 if Present (Comp) then
5540 Ccount := Ccount + 1;
5542 -- We need a full overlap check if record positions non-monotonic
5544 if Fbit <= Max_Bit_So_Far then
5545 Overlap_Check_Required := True;
5548 Max_Bit_So_Far := Lbit;
5550 -- Check bit position out of range of specified size
5552 if Has_Size_Clause (Rectype)
5553 and then Esize (Rectype) <= Lbit
5556 ("bit number out of range of specified size",
5559 -- Check for overlap with tag field
5562 if Is_Tagged_Type (Rectype)
5563 and then Fbit < System_Address_Size
5566 ("component overlaps tag field of&",
5567 Component_Name (CC), Rectype);
5568 Overlap_Detected := True;
5576 -- Check parent overlap if component might overlap parent field
5578 if Present (Tagged_Parent)
5579 and then Fbit <= Parent_Last_Bit
5581 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
5582 while Present (Pcomp) loop
5583 if not Is_Tag (Pcomp)
5584 and then Chars (Pcomp) /= Name_uParent
5586 Check_Component_Overlap (Comp, Pcomp);
5589 Next_Component_Or_Discriminant (Pcomp);
5597 -- Now that we have processed all the component clauses, check for
5598 -- overlap. We have to leave this till last, since the components can
5599 -- appear in any arbitrary order in the representation clause.
5601 -- We do not need this check if all specified ranges were monotonic,
5602 -- as recorded by Overlap_Check_Required being False at this stage.
5604 -- This first section checks if there are any overlapping entries at
5605 -- all. It does this by sorting all entries and then seeing if there are
5606 -- any overlaps. If there are none, then that is decisive, but if there
5607 -- are overlaps, they may still be OK (they may result from fields in
5608 -- different variants).
5610 if Overlap_Check_Required then
5611 Overlap_Check1 : declare
5613 OC_Fbit : array (0 .. Ccount) of Uint;
5614 -- First-bit values for component clauses, the value is the offset
5615 -- of the first bit of the field from start of record. The zero
5616 -- entry is for use in sorting.
5618 OC_Lbit : array (0 .. Ccount) of Uint;
5619 -- Last-bit values for component clauses, the value is the offset
5620 -- of the last bit of the field from start of record. The zero
5621 -- entry is for use in sorting.
5623 OC_Count : Natural := 0;
5624 -- Count of entries in OC_Fbit and OC_Lbit
5626 function OC_Lt (Op1, Op2 : Natural) return Boolean;
5627 -- Compare routine for Sort
5629 procedure OC_Move (From : Natural; To : Natural);
5630 -- Move routine for Sort
5632 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
5638 function OC_Lt (Op1, Op2 : Natural) return Boolean is
5640 return OC_Fbit (Op1) < OC_Fbit (Op2);
5647 procedure OC_Move (From : Natural; To : Natural) is
5649 OC_Fbit (To) := OC_Fbit (From);
5650 OC_Lbit (To) := OC_Lbit (From);
5653 -- Start of processing for Overlap_Check
5656 CC := First (Component_Clauses (N));
5657 while Present (CC) loop
5659 -- Exclude component clause already marked in error
5661 if not Error_Posted (CC) then
5664 if Present (Comp) then
5665 OC_Count := OC_Count + 1;
5666 OC_Fbit (OC_Count) := Fbit;
5667 OC_Lbit (OC_Count) := Lbit;
5674 Sorting.Sort (OC_Count);
5676 Overlap_Check_Required := False;
5677 for J in 1 .. OC_Count - 1 loop
5678 if OC_Lbit (J) >= OC_Fbit (J + 1) then
5679 Overlap_Check_Required := True;
5686 -- If Overlap_Check_Required is still True, then we have to do the full
5687 -- scale overlap check, since we have at least two fields that do
5688 -- overlap, and we need to know if that is OK since they are in
5689 -- different variant, or whether we have a definite problem.
5691 if Overlap_Check_Required then
5692 Overlap_Check2 : declare
5693 C1_Ent, C2_Ent : Entity_Id;
5694 -- Entities of components being checked for overlap
5697 -- Component_List node whose Component_Items are being checked
5700 -- Component declaration for component being checked
5703 C1_Ent := First_Entity (Base_Type (Rectype));
5705 -- Loop through all components in record. For each component check
5706 -- for overlap with any of the preceding elements on the component
5707 -- list containing the component and also, if the component is in
5708 -- a variant, check against components outside the case structure.
5709 -- This latter test is repeated recursively up the variant tree.
5711 Main_Component_Loop : while Present (C1_Ent) loop
5712 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
5713 goto Continue_Main_Component_Loop;
5716 -- Skip overlap check if entity has no declaration node. This
5717 -- happens with discriminants in constrained derived types.
5718 -- Possibly we are missing some checks as a result, but that
5719 -- does not seem terribly serious.
5721 if No (Declaration_Node (C1_Ent)) then
5722 goto Continue_Main_Component_Loop;
5725 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
5727 -- Loop through component lists that need checking. Check the
5728 -- current component list and all lists in variants above us.
5730 Component_List_Loop : loop
5732 -- If derived type definition, go to full declaration
5733 -- If at outer level, check discriminants if there are any.
5735 if Nkind (Clist) = N_Derived_Type_Definition then
5736 Clist := Parent (Clist);
5739 -- Outer level of record definition, check discriminants
5741 if Nkind_In (Clist, N_Full_Type_Declaration,
5742 N_Private_Type_Declaration)
5744 if Has_Discriminants (Defining_Identifier (Clist)) then
5746 First_Discriminant (Defining_Identifier (Clist));
5747 while Present (C2_Ent) loop
5748 exit when C1_Ent = C2_Ent;
5749 Check_Component_Overlap (C1_Ent, C2_Ent);
5750 Next_Discriminant (C2_Ent);
5754 -- Record extension case
5756 elsif Nkind (Clist) = N_Derived_Type_Definition then
5759 -- Otherwise check one component list
5762 Citem := First (Component_Items (Clist));
5763 while Present (Citem) loop
5764 if Nkind (Citem) = N_Component_Declaration then
5765 C2_Ent := Defining_Identifier (Citem);
5766 exit when C1_Ent = C2_Ent;
5767 Check_Component_Overlap (C1_Ent, C2_Ent);
5774 -- Check for variants above us (the parent of the Clist can
5775 -- be a variant, in which case its parent is a variant part,
5776 -- and the parent of the variant part is a component list
5777 -- whose components must all be checked against the current
5778 -- component for overlap).
5780 if Nkind (Parent (Clist)) = N_Variant then
5781 Clist := Parent (Parent (Parent (Clist)));
5783 -- Check for possible discriminant part in record, this
5784 -- is treated essentially as another level in the
5785 -- recursion. For this case the parent of the component
5786 -- list is the record definition, and its parent is the
5787 -- full type declaration containing the discriminant
5790 elsif Nkind (Parent (Clist)) = N_Record_Definition then
5791 Clist := Parent (Parent ((Clist)));
5793 -- If neither of these two cases, we are at the top of
5797 exit Component_List_Loop;
5799 end loop Component_List_Loop;
5801 <<Continue_Main_Component_Loop>>
5802 Next_Entity (C1_Ent);
5804 end loop Main_Component_Loop;
5808 -- The following circuit deals with warning on record holes (gaps). We
5809 -- skip this check if overlap was detected, since it makes sense for the
5810 -- programmer to fix this illegality before worrying about warnings.
5812 if not Overlap_Detected and Warn_On_Record_Holes then
5813 Record_Hole_Check : declare
5814 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
5815 -- Full declaration of record type
5817 procedure Check_Component_List
5821 -- Check component list CL for holes. The starting bit should be
5822 -- Sbit. which is zero for the main record component list and set
5823 -- appropriately for recursive calls for variants. DS is set to
5824 -- a list of discriminant specifications to be included in the
5825 -- consideration of components. It is No_List if none to consider.
5827 --------------------------
5828 -- Check_Component_List --
5829 --------------------------
5831 procedure Check_Component_List
5839 Compl := Integer (List_Length (Component_Items (CL)));
5841 if DS /= No_List then
5842 Compl := Compl + Integer (List_Length (DS));
5846 Comps : array (Natural range 0 .. Compl) of Entity_Id;
5847 -- Gather components (zero entry is for sort routine)
5849 Ncomps : Natural := 0;
5850 -- Number of entries stored in Comps (starting at Comps (1))
5853 -- One component item or discriminant specification
5856 -- Starting bit for next component
5864 function Lt (Op1, Op2 : Natural) return Boolean;
5865 -- Compare routine for Sort
5867 procedure Move (From : Natural; To : Natural);
5868 -- Move routine for Sort
5870 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
5876 function Lt (Op1, Op2 : Natural) return Boolean is
5878 return Component_Bit_Offset (Comps (Op1))
5880 Component_Bit_Offset (Comps (Op2));
5887 procedure Move (From : Natural; To : Natural) is
5889 Comps (To) := Comps (From);
5893 -- Gather discriminants into Comp
5895 if DS /= No_List then
5896 Citem := First (DS);
5897 while Present (Citem) loop
5898 if Nkind (Citem) = N_Discriminant_Specification then
5900 Ent : constant Entity_Id :=
5901 Defining_Identifier (Citem);
5903 if Ekind (Ent) = E_Discriminant then
5904 Ncomps := Ncomps + 1;
5905 Comps (Ncomps) := Ent;
5914 -- Gather component entities into Comp
5916 Citem := First (Component_Items (CL));
5917 while Present (Citem) loop
5918 if Nkind (Citem) = N_Component_Declaration then
5919 Ncomps := Ncomps + 1;
5920 Comps (Ncomps) := Defining_Identifier (Citem);
5926 -- Now sort the component entities based on the first bit.
5927 -- Note we already know there are no overlapping components.
5929 Sorting.Sort (Ncomps);
5931 -- Loop through entries checking for holes
5934 for J in 1 .. Ncomps loop
5936 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
5938 if Error_Msg_Uint_1 > 0 then
5940 ("?^-bit gap before component&",
5941 Component_Name (Component_Clause (CEnt)), CEnt);
5944 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
5947 -- Process variant parts recursively if present
5949 if Present (Variant_Part (CL)) then
5950 Variant := First (Variants (Variant_Part (CL)));
5951 while Present (Variant) loop
5952 Check_Component_List
5953 (Component_List (Variant), Nbit, No_List);
5958 end Check_Component_List;
5960 -- Start of processing for Record_Hole_Check
5967 if Is_Tagged_Type (Rectype) then
5968 Sbit := UI_From_Int (System_Address_Size);
5973 if Nkind (Decl) = N_Full_Type_Declaration
5974 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
5976 Check_Component_List
5977 (Component_List (Type_Definition (Decl)),
5979 Discriminant_Specifications (Decl));
5982 end Record_Hole_Check;
5985 -- For records that have component clauses for all components, and whose
5986 -- size is less than or equal to 32, we need to know the size in the
5987 -- front end to activate possible packed array processing where the
5988 -- component type is a record.
5990 -- At this stage Hbit + 1 represents the first unused bit from all the
5991 -- component clauses processed, so if the component clauses are
5992 -- complete, then this is the length of the record.
5994 -- For records longer than System.Storage_Unit, and for those where not
5995 -- all components have component clauses, the back end determines the
5996 -- length (it may for example be appropriate to round up the size
5997 -- to some convenient boundary, based on alignment considerations, etc).
5999 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
6001 -- Nothing to do if at least one component has no component clause
6003 Comp := First_Component_Or_Discriminant (Rectype);
6004 while Present (Comp) loop
6005 exit when No (Component_Clause (Comp));
6006 Next_Component_Or_Discriminant (Comp);
6009 -- If we fall out of loop, all components have component clauses
6010 -- and so we can set the size to the maximum value.
6013 Set_RM_Size (Rectype, Hbit + 1);
6016 end Check_Record_Representation_Clause;
6022 procedure Check_Size
6026 Biased : out Boolean)
6028 UT : constant Entity_Id := Underlying_Type (T);
6034 -- Dismiss cases for generic types or types with previous errors
6037 or else UT = Any_Type
6038 or else Is_Generic_Type (UT)
6039 or else Is_Generic_Type (Root_Type (UT))
6043 -- Check case of bit packed array
6045 elsif Is_Array_Type (UT)
6046 and then Known_Static_Component_Size (UT)
6047 and then Is_Bit_Packed_Array (UT)
6055 Asiz := Component_Size (UT);
6056 Indx := First_Index (UT);
6058 Ityp := Etype (Indx);
6060 -- If non-static bound, then we are not in the business of
6061 -- trying to check the length, and indeed an error will be
6062 -- issued elsewhere, since sizes of non-static array types
6063 -- cannot be set implicitly or explicitly.
6065 if not Is_Static_Subtype (Ityp) then
6069 -- Otherwise accumulate next dimension
6071 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
6072 Expr_Value (Type_Low_Bound (Ityp)) +
6076 exit when No (Indx);
6082 Error_Msg_Uint_1 := Asiz;
6084 ("size for& too small, minimum allowed is ^", N, T);
6085 Set_Esize (T, Asiz);
6086 Set_RM_Size (T, Asiz);
6090 -- All other composite types are ignored
6092 elsif Is_Composite_Type (UT) then
6095 -- For fixed-point types, don't check minimum if type is not frozen,
6096 -- since we don't know all the characteristics of the type that can
6097 -- affect the size (e.g. a specified small) till freeze time.
6099 elsif Is_Fixed_Point_Type (UT)
6100 and then not Is_Frozen (UT)
6104 -- Cases for which a minimum check is required
6107 -- Ignore if specified size is correct for the type
6109 if Known_Esize (UT) and then Siz = Esize (UT) then
6113 -- Otherwise get minimum size
6115 M := UI_From_Int (Minimum_Size (UT));
6119 -- Size is less than minimum size, but one possibility remains
6120 -- that we can manage with the new size if we bias the type.
6122 M := UI_From_Int (Minimum_Size (UT, Biased => True));
6125 Error_Msg_Uint_1 := M;
6127 ("size for& too small, minimum allowed is ^", N, T);
6137 -------------------------
6138 -- Get_Alignment_Value --
6139 -------------------------
6141 function Get_Alignment_Value (Expr : Node_Id) return Uint is
6142 Align : constant Uint := Static_Integer (Expr);
6145 if Align = No_Uint then
6148 elsif Align <= 0 then
6149 Error_Msg_N ("alignment value must be positive", Expr);
6153 for J in Int range 0 .. 64 loop
6155 M : constant Uint := Uint_2 ** J;
6158 exit when M = Align;
6162 ("alignment value must be power of 2", Expr);
6170 end Get_Alignment_Value;
6176 procedure Initialize is
6178 Address_Clause_Checks.Init;
6179 Independence_Checks.Init;
6180 Unchecked_Conversions.Init;
6183 -------------------------
6184 -- Is_Operational_Item --
6185 -------------------------
6187 function Is_Operational_Item (N : Node_Id) return Boolean is
6189 if Nkind (N) /= N_Attribute_Definition_Clause then
6193 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
6195 return Id = Attribute_Input
6196 or else Id = Attribute_Output
6197 or else Id = Attribute_Read
6198 or else Id = Attribute_Write
6199 or else Id = Attribute_External_Tag;
6202 end Is_Operational_Item;
6208 function Minimum_Size
6210 Biased : Boolean := False) return Nat
6212 Lo : Uint := No_Uint;
6213 Hi : Uint := No_Uint;
6214 LoR : Ureal := No_Ureal;
6215 HiR : Ureal := No_Ureal;
6216 LoSet : Boolean := False;
6217 HiSet : Boolean := False;
6221 R_Typ : constant Entity_Id := Root_Type (T);
6224 -- If bad type, return 0
6226 if T = Any_Type then
6229 -- For generic types, just return zero. There cannot be any legitimate
6230 -- need to know such a size, but this routine may be called with a
6231 -- generic type as part of normal processing.
6233 elsif Is_Generic_Type (R_Typ)
6234 or else R_Typ = Any_Type
6238 -- Access types. Normally an access type cannot have a size smaller
6239 -- than the size of System.Address. The exception is on VMS, where
6240 -- we have short and long addresses, and it is possible for an access
6241 -- type to have a short address size (and thus be less than the size
6242 -- of System.Address itself). We simply skip the check for VMS, and
6243 -- leave it to the back end to do the check.
6245 elsif Is_Access_Type (T) then
6246 if OpenVMS_On_Target then
6249 return System_Address_Size;
6252 -- Floating-point types
6254 elsif Is_Floating_Point_Type (T) then
6255 return UI_To_Int (Esize (R_Typ));
6259 elsif Is_Discrete_Type (T) then
6261 -- The following loop is looking for the nearest compile time known
6262 -- bounds following the ancestor subtype chain. The idea is to find
6263 -- the most restrictive known bounds information.
6267 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6272 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
6273 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
6280 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
6281 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
6287 Ancest := Ancestor_Subtype (Ancest);
6290 Ancest := Base_Type (T);
6292 if Is_Generic_Type (Ancest) then
6298 -- Fixed-point types. We can't simply use Expr_Value to get the
6299 -- Corresponding_Integer_Value values of the bounds, since these do not
6300 -- get set till the type is frozen, and this routine can be called
6301 -- before the type is frozen. Similarly the test for bounds being static
6302 -- needs to include the case where we have unanalyzed real literals for
6305 elsif Is_Fixed_Point_Type (T) then
6307 -- The following loop is looking for the nearest compile time known
6308 -- bounds following the ancestor subtype chain. The idea is to find
6309 -- the most restrictive known bounds information.
6313 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6317 -- Note: In the following two tests for LoSet and HiSet, it may
6318 -- seem redundant to test for N_Real_Literal here since normally
6319 -- one would assume that the test for the value being known at
6320 -- compile time includes this case. However, there is a glitch.
6321 -- If the real literal comes from folding a non-static expression,
6322 -- then we don't consider any non- static expression to be known
6323 -- at compile time if we are in configurable run time mode (needed
6324 -- in some cases to give a clearer definition of what is and what
6325 -- is not accepted). So the test is indeed needed. Without it, we
6326 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
6329 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
6330 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
6332 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
6339 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
6340 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
6342 HiR := Expr_Value_R (Type_High_Bound (Ancest));
6348 Ancest := Ancestor_Subtype (Ancest);
6351 Ancest := Base_Type (T);
6353 if Is_Generic_Type (Ancest) then
6359 Lo := UR_To_Uint (LoR / Small_Value (T));
6360 Hi := UR_To_Uint (HiR / Small_Value (T));
6362 -- No other types allowed
6365 raise Program_Error;
6368 -- Fall through with Hi and Lo set. Deal with biased case
6371 and then not Is_Fixed_Point_Type (T)
6372 and then not (Is_Enumeration_Type (T)
6373 and then Has_Non_Standard_Rep (T)))
6374 or else Has_Biased_Representation (T)
6380 -- Signed case. Note that we consider types like range 1 .. -1 to be
6381 -- signed for the purpose of computing the size, since the bounds have
6382 -- to be accommodated in the base type.
6384 if Lo < 0 or else Hi < 0 then
6388 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
6389 -- Note that we accommodate the case where the bounds cross. This
6390 -- can happen either because of the way the bounds are declared
6391 -- or because of the algorithm in Freeze_Fixed_Point_Type.
6405 -- If both bounds are positive, make sure that both are represen-
6406 -- table in the case where the bounds are crossed. This can happen
6407 -- either because of the way the bounds are declared, or because of
6408 -- the algorithm in Freeze_Fixed_Point_Type.
6414 -- S = size, (can accommodate 0 .. (2**size - 1))
6417 while Hi >= Uint_2 ** S loop
6425 ---------------------------
6426 -- New_Stream_Subprogram --
6427 ---------------------------
6429 procedure New_Stream_Subprogram
6433 Nam : TSS_Name_Type)
6435 Loc : constant Source_Ptr := Sloc (N);
6436 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
6437 Subp_Id : Entity_Id;
6438 Subp_Decl : Node_Id;
6442 Defer_Declaration : constant Boolean :=
6443 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
6444 -- For a tagged type, there is a declaration for each stream attribute
6445 -- at the freeze point, and we must generate only a completion of this
6446 -- declaration. We do the same for private types, because the full view
6447 -- might be tagged. Otherwise we generate a declaration at the point of
6448 -- the attribute definition clause.
6450 function Build_Spec return Node_Id;
6451 -- Used for declaration and renaming declaration, so that this is
6452 -- treated as a renaming_as_body.
6458 function Build_Spec return Node_Id is
6459 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
6462 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
6465 Subp_Id := Make_Defining_Identifier (Loc, Sname);
6467 -- S : access Root_Stream_Type'Class
6469 Formals := New_List (
6470 Make_Parameter_Specification (Loc,
6471 Defining_Identifier =>
6472 Make_Defining_Identifier (Loc, Name_S),
6474 Make_Access_Definition (Loc,
6477 Designated_Type (Etype (F)), Loc))));
6479 if Nam = TSS_Stream_Input then
6480 Spec := Make_Function_Specification (Loc,
6481 Defining_Unit_Name => Subp_Id,
6482 Parameter_Specifications => Formals,
6483 Result_Definition => T_Ref);
6488 Make_Parameter_Specification (Loc,
6489 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
6490 Out_Present => Out_P,
6491 Parameter_Type => T_Ref));
6494 Make_Procedure_Specification (Loc,
6495 Defining_Unit_Name => Subp_Id,
6496 Parameter_Specifications => Formals);
6502 -- Start of processing for New_Stream_Subprogram
6505 F := First_Formal (Subp);
6507 if Ekind (Subp) = E_Procedure then
6508 Etyp := Etype (Next_Formal (F));
6510 Etyp := Etype (Subp);
6513 -- Prepare subprogram declaration and insert it as an action on the
6514 -- clause node. The visibility for this entity is used to test for
6515 -- visibility of the attribute definition clause (in the sense of
6516 -- 8.3(23) as amended by AI-195).
6518 if not Defer_Declaration then
6520 Make_Subprogram_Declaration (Loc,
6521 Specification => Build_Spec);
6523 -- For a tagged type, there is always a visible declaration for each
6524 -- stream TSS (it is a predefined primitive operation), and the
6525 -- completion of this declaration occurs at the freeze point, which is
6526 -- not always visible at places where the attribute definition clause is
6527 -- visible. So, we create a dummy entity here for the purpose of
6528 -- tracking the visibility of the attribute definition clause itself.
6532 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
6534 Make_Object_Declaration (Loc,
6535 Defining_Identifier => Subp_Id,
6536 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
6539 Insert_Action (N, Subp_Decl);
6540 Set_Entity (N, Subp_Id);
6543 Make_Subprogram_Renaming_Declaration (Loc,
6544 Specification => Build_Spec,
6545 Name => New_Reference_To (Subp, Loc));
6547 if Defer_Declaration then
6548 Set_TSS (Base_Type (Ent), Subp_Id);
6550 Insert_Action (N, Subp_Decl);
6551 Copy_TSS (Subp_Id, Base_Type (Ent));
6553 end New_Stream_Subprogram;
6555 ------------------------
6556 -- Rep_Item_Too_Early --
6557 ------------------------
6559 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
6561 -- Cannot apply non-operational rep items to generic types
6563 if Is_Operational_Item (N) then
6567 and then Is_Generic_Type (Root_Type (T))
6569 Error_Msg_N ("representation item not allowed for generic type", N);
6573 -- Otherwise check for incomplete type
6575 if Is_Incomplete_Or_Private_Type (T)
6576 and then No (Underlying_Type (T))
6579 ("representation item must be after full type declaration", N);
6582 -- If the type has incomplete components, a representation clause is
6583 -- illegal but stream attributes and Convention pragmas are correct.
6585 elsif Has_Private_Component (T) then
6586 if Nkind (N) = N_Pragma then
6590 ("representation item must appear after type is fully defined",
6597 end Rep_Item_Too_Early;
6599 -----------------------
6600 -- Rep_Item_Too_Late --
6601 -----------------------
6603 function Rep_Item_Too_Late
6606 FOnly : Boolean := False) return Boolean
6609 Parent_Type : Entity_Id;
6612 -- Output the too late message. Note that this is not considered a
6613 -- serious error, since the effect is simply that we ignore the
6614 -- representation clause in this case.
6620 procedure Too_Late is
6622 Error_Msg_N ("|representation item appears too late!", N);
6625 -- Start of processing for Rep_Item_Too_Late
6628 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
6629 -- types, which may be frozen if they appear in a representation clause
6630 -- for a local type.
6633 and then not From_With_Type (T)
6636 S := First_Subtype (T);
6638 if Present (Freeze_Node (S)) then
6640 ("?no more representation items for }", Freeze_Node (S), S);
6645 -- Check for case of non-tagged derived type whose parent either has
6646 -- primitive operations, or is a by reference type (RM 13.1(10)).
6650 and then Is_Derived_Type (T)
6651 and then not Is_Tagged_Type (T)
6653 Parent_Type := Etype (Base_Type (T));
6655 if Has_Primitive_Operations (Parent_Type) then
6658 ("primitive operations already defined for&!", N, Parent_Type);
6661 elsif Is_By_Reference_Type (Parent_Type) then
6664 ("parent type & is a by reference type!", N, Parent_Type);
6669 -- No error, link item into head of chain of rep items for the entity,
6670 -- but avoid chaining if we have an overloadable entity, and the pragma
6671 -- is one that can apply to multiple overloaded entities.
6673 if Is_Overloadable (T)
6674 and then Nkind (N) = N_Pragma
6677 Pname : constant Name_Id := Pragma_Name (N);
6679 if Pname = Name_Convention or else
6680 Pname = Name_Import or else
6681 Pname = Name_Export or else
6682 Pname = Name_External or else
6683 Pname = Name_Interface
6690 Record_Rep_Item (T, N);
6692 end Rep_Item_Too_Late;
6694 -------------------------------------
6695 -- Replace_Type_References_Generic --
6696 -------------------------------------
6698 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
6700 function Replace_Node (N : Node_Id) return Traverse_Result;
6701 -- Processes a single node in the traversal procedure below, checking
6702 -- if node N should be replaced, and if so, doing the replacement.
6704 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
6705 -- This instantiation provides the body of Replace_Type_References
6711 function Replace_Node (N : Node_Id) return Traverse_Result is
6716 -- Case of identifier
6718 if Nkind (N) = N_Identifier then
6720 -- If not the type name, all done with this node
6722 if Chars (N) /= TName then
6725 -- Otherwise do the replacement and we are done with this node
6728 Replace_Type_Reference (N);
6732 -- Case of selected component (which is what a qualification
6733 -- looks like in the unanalyzed tree, which is what we have.
6735 elsif Nkind (N) = N_Selected_Component then
6737 -- If selector name is not our type, keeping going (we might
6738 -- still have an occurrence of the type in the prefix).
6740 if Nkind (Selector_Name (N)) /= N_Identifier
6741 or else Chars (Selector_Name (N)) /= TName
6745 -- Selector name is our type, check qualification
6748 -- Loop through scopes and prefixes, doing comparison
6753 -- Continue if no more scopes or scope with no name
6755 if No (S) or else Nkind (S) not in N_Has_Chars then
6759 -- Do replace if prefix is an identifier matching the
6760 -- scope that we are currently looking at.
6762 if Nkind (P) = N_Identifier
6763 and then Chars (P) = Chars (S)
6765 Replace_Type_Reference (N);
6769 -- Go check scope above us if prefix is itself of the
6770 -- form of a selected component, whose selector matches
6771 -- the scope we are currently looking at.
6773 if Nkind (P) = N_Selected_Component
6774 and then Nkind (Selector_Name (P)) = N_Identifier
6775 and then Chars (Selector_Name (P)) = Chars (S)
6780 -- For anything else, we don't have a match, so keep on
6781 -- going, there are still some weird cases where we may
6782 -- still have a replacement within the prefix.
6790 -- Continue for any other node kind
6798 Replace_Type_Refs (N);
6799 end Replace_Type_References_Generic;
6801 -------------------------
6802 -- Same_Representation --
6803 -------------------------
6805 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
6806 T1 : constant Entity_Id := Underlying_Type (Typ1);
6807 T2 : constant Entity_Id := Underlying_Type (Typ2);
6810 -- A quick check, if base types are the same, then we definitely have
6811 -- the same representation, because the subtype specific representation
6812 -- attributes (Size and Alignment) do not affect representation from
6813 -- the point of view of this test.
6815 if Base_Type (T1) = Base_Type (T2) then
6818 elsif Is_Private_Type (Base_Type (T2))
6819 and then Base_Type (T1) = Full_View (Base_Type (T2))
6824 -- Tagged types never have differing representations
6826 if Is_Tagged_Type (T1) then
6830 -- Representations are definitely different if conventions differ
6832 if Convention (T1) /= Convention (T2) then
6836 -- Representations are different if component alignments differ
6838 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
6840 (Is_Record_Type (T2) or else Is_Array_Type (T2))
6841 and then Component_Alignment (T1) /= Component_Alignment (T2)
6846 -- For arrays, the only real issue is component size. If we know the
6847 -- component size for both arrays, and it is the same, then that's
6848 -- good enough to know we don't have a change of representation.
6850 if Is_Array_Type (T1) then
6851 if Known_Component_Size (T1)
6852 and then Known_Component_Size (T2)
6853 and then Component_Size (T1) = Component_Size (T2)
6859 -- Types definitely have same representation if neither has non-standard
6860 -- representation since default representations are always consistent.
6861 -- If only one has non-standard representation, and the other does not,
6862 -- then we consider that they do not have the same representation. They
6863 -- might, but there is no way of telling early enough.
6865 if Has_Non_Standard_Rep (T1) then
6866 if not Has_Non_Standard_Rep (T2) then
6870 return not Has_Non_Standard_Rep (T2);
6873 -- Here the two types both have non-standard representation, and we need
6874 -- to determine if they have the same non-standard representation.
6876 -- For arrays, we simply need to test if the component sizes are the
6877 -- same. Pragma Pack is reflected in modified component sizes, so this
6878 -- check also deals with pragma Pack.
6880 if Is_Array_Type (T1) then
6881 return Component_Size (T1) = Component_Size (T2);
6883 -- Tagged types always have the same representation, because it is not
6884 -- possible to specify different representations for common fields.
6886 elsif Is_Tagged_Type (T1) then
6889 -- Case of record types
6891 elsif Is_Record_Type (T1) then
6893 -- Packed status must conform
6895 if Is_Packed (T1) /= Is_Packed (T2) then
6898 -- Otherwise we must check components. Typ2 maybe a constrained
6899 -- subtype with fewer components, so we compare the components
6900 -- of the base types.
6903 Record_Case : declare
6904 CD1, CD2 : Entity_Id;
6906 function Same_Rep return Boolean;
6907 -- CD1 and CD2 are either components or discriminants. This
6908 -- function tests whether the two have the same representation
6914 function Same_Rep return Boolean is
6916 if No (Component_Clause (CD1)) then
6917 return No (Component_Clause (CD2));
6921 Present (Component_Clause (CD2))
6923 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
6925 Esize (CD1) = Esize (CD2);
6929 -- Start of processing for Record_Case
6932 if Has_Discriminants (T1) then
6933 CD1 := First_Discriminant (T1);
6934 CD2 := First_Discriminant (T2);
6936 -- The number of discriminants may be different if the
6937 -- derived type has fewer (constrained by values). The
6938 -- invisible discriminants retain the representation of
6939 -- the original, so the discrepancy does not per se
6940 -- indicate a different representation.
6943 and then Present (CD2)
6945 if not Same_Rep then
6948 Next_Discriminant (CD1);
6949 Next_Discriminant (CD2);
6954 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
6955 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
6957 while Present (CD1) loop
6958 if not Same_Rep then
6961 Next_Component (CD1);
6962 Next_Component (CD2);
6970 -- For enumeration types, we must check each literal to see if the
6971 -- representation is the same. Note that we do not permit enumeration
6972 -- representation clauses for Character and Wide_Character, so these
6973 -- cases were already dealt with.
6975 elsif Is_Enumeration_Type (T1) then
6976 Enumeration_Case : declare
6980 L1 := First_Literal (T1);
6981 L2 := First_Literal (T2);
6983 while Present (L1) loop
6984 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
6994 end Enumeration_Case;
6996 -- Any other types have the same representation for these purposes
7001 end Same_Representation;
7007 procedure Set_Biased
7011 Biased : Boolean := True)
7015 Set_Has_Biased_Representation (E);
7017 if Warn_On_Biased_Representation then
7019 ("?" & Msg & " forces biased representation for&", N, E);
7024 --------------------
7025 -- Set_Enum_Esize --
7026 --------------------
7028 procedure Set_Enum_Esize (T : Entity_Id) is
7036 -- Find the minimum standard size (8,16,32,64) that fits
7038 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
7039 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
7042 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
7043 Sz := Standard_Character_Size; -- May be > 8 on some targets
7045 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
7048 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
7051 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
7056 if Hi < Uint_2**08 then
7057 Sz := Standard_Character_Size; -- May be > 8 on some targets
7059 elsif Hi < Uint_2**16 then
7062 elsif Hi < Uint_2**32 then
7065 else pragma Assert (Hi < Uint_2**63);
7070 -- That minimum is the proper size unless we have a foreign convention
7071 -- and the size required is 32 or less, in which case we bump the size
7072 -- up to 32. This is required for C and C++ and seems reasonable for
7073 -- all other foreign conventions.
7075 if Has_Foreign_Convention (T)
7076 and then Esize (T) < Standard_Integer_Size
7078 Init_Esize (T, Standard_Integer_Size);
7084 ------------------------------
7085 -- Validate_Address_Clauses --
7086 ------------------------------
7088 procedure Validate_Address_Clauses is
7090 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
7092 ACCR : Address_Clause_Check_Record
7093 renames Address_Clause_Checks.Table (J);
7104 -- Skip processing of this entry if warning already posted
7106 if not Address_Warning_Posted (ACCR.N) then
7108 Expr := Original_Node (Expression (ACCR.N));
7112 X_Alignment := Alignment (ACCR.X);
7113 Y_Alignment := Alignment (ACCR.Y);
7115 -- Similarly obtain sizes
7117 X_Size := Esize (ACCR.X);
7118 Y_Size := Esize (ACCR.Y);
7120 -- Check for large object overlaying smaller one
7123 and then X_Size > Uint_0
7124 and then X_Size > Y_Size
7127 ("?& overlays smaller object", ACCR.N, ACCR.X);
7129 ("\?program execution may be erroneous", ACCR.N);
7130 Error_Msg_Uint_1 := X_Size;
7132 ("\?size of & is ^", ACCR.N, ACCR.X);
7133 Error_Msg_Uint_1 := Y_Size;
7135 ("\?size of & is ^", ACCR.N, ACCR.Y);
7137 -- Check for inadequate alignment, both of the base object
7138 -- and of the offset, if any.
7140 -- Note: we do not check the alignment if we gave a size
7141 -- warning, since it would likely be redundant.
7143 elsif Y_Alignment /= Uint_0
7144 and then (Y_Alignment < X_Alignment
7147 Nkind (Expr) = N_Attribute_Reference
7149 Attribute_Name (Expr) = Name_Address
7151 Has_Compatible_Alignment
7152 (ACCR.X, Prefix (Expr))
7153 /= Known_Compatible))
7156 ("?specified address for& may be inconsistent "
7160 ("\?program execution may be erroneous (RM 13.3(27))",
7162 Error_Msg_Uint_1 := X_Alignment;
7164 ("\?alignment of & is ^",
7166 Error_Msg_Uint_1 := Y_Alignment;
7168 ("\?alignment of & is ^",
7170 if Y_Alignment >= X_Alignment then
7172 ("\?but offset is not multiple of alignment",
7179 end Validate_Address_Clauses;
7181 ---------------------------
7182 -- Validate_Independence --
7183 ---------------------------
7185 procedure Validate_Independence is
7186 SU : constant Uint := UI_From_Int (System_Storage_Unit);
7194 procedure Check_Array_Type (Atyp : Entity_Id);
7195 -- Checks if the array type Atyp has independent components, and
7196 -- if not, outputs an appropriate set of error messages.
7198 procedure No_Independence;
7199 -- Output message that independence cannot be guaranteed
7201 function OK_Component (C : Entity_Id) return Boolean;
7202 -- Checks one component to see if it is independently accessible, and
7203 -- if so yields True, otherwise yields False if independent access
7204 -- cannot be guaranteed. This is a conservative routine, it only
7205 -- returns True if it knows for sure, it returns False if it knows
7206 -- there is a problem, or it cannot be sure there is no problem.
7208 procedure Reason_Bad_Component (C : Entity_Id);
7209 -- Outputs continuation message if a reason can be determined for
7210 -- the component C being bad.
7212 ----------------------
7213 -- Check_Array_Type --
7214 ----------------------
7216 procedure Check_Array_Type (Atyp : Entity_Id) is
7217 Ctyp : constant Entity_Id := Component_Type (Atyp);
7220 -- OK if no alignment clause, no pack, and no component size
7222 if not Has_Component_Size_Clause (Atyp)
7223 and then not Has_Alignment_Clause (Atyp)
7224 and then not Is_Packed (Atyp)
7229 -- Check actual component size
7231 if not Known_Component_Size (Atyp)
7232 or else not (Addressable (Component_Size (Atyp))
7233 and then Component_Size (Atyp) < 64)
7234 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
7238 -- Bad component size, check reason
7240 if Has_Component_Size_Clause (Atyp) then
7242 Get_Attribute_Definition_Clause
7243 (Atyp, Attribute_Component_Size);
7246 Error_Msg_Sloc := Sloc (P);
7247 Error_Msg_N ("\because of Component_Size clause#", N);
7252 if Is_Packed (Atyp) then
7253 P := Get_Rep_Pragma (Atyp, Name_Pack);
7256 Error_Msg_Sloc := Sloc (P);
7257 Error_Msg_N ("\because of pragma Pack#", N);
7262 -- No reason found, just return
7267 -- Array type is OK independence-wise
7270 end Check_Array_Type;
7272 ---------------------
7273 -- No_Independence --
7274 ---------------------
7276 procedure No_Independence is
7278 if Pragma_Name (N) = Name_Independent then
7280 ("independence cannot be guaranteed for&", N, E);
7283 ("independent components cannot be guaranteed for&", N, E);
7285 end No_Independence;
7291 function OK_Component (C : Entity_Id) return Boolean is
7292 Rec : constant Entity_Id := Scope (C);
7293 Ctyp : constant Entity_Id := Etype (C);
7296 -- OK if no component clause, no Pack, and no alignment clause
7298 if No (Component_Clause (C))
7299 and then not Is_Packed (Rec)
7300 and then not Has_Alignment_Clause (Rec)
7305 -- Here we look at the actual component layout. A component is
7306 -- addressable if its size is a multiple of the Esize of the
7307 -- component type, and its starting position in the record has
7308 -- appropriate alignment, and the record itself has appropriate
7309 -- alignment to guarantee the component alignment.
7311 -- Make sure sizes are static, always assume the worst for any
7312 -- cases where we cannot check static values.
7314 if not (Known_Static_Esize (C)
7315 and then Known_Static_Esize (Ctyp))
7320 -- Size of component must be addressable or greater than 64 bits
7321 -- and a multiple of bytes.
7323 if not Addressable (Esize (C))
7324 and then Esize (C) < Uint_64
7329 -- Check size is proper multiple
7331 if Esize (C) mod Esize (Ctyp) /= 0 then
7335 -- Check alignment of component is OK
7337 if not Known_Component_Bit_Offset (C)
7338 or else Component_Bit_Offset (C) < Uint_0
7339 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
7344 -- Check alignment of record type is OK
7346 if not Known_Alignment (Rec)
7347 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7352 -- All tests passed, component is addressable
7357 --------------------------
7358 -- Reason_Bad_Component --
7359 --------------------------
7361 procedure Reason_Bad_Component (C : Entity_Id) is
7362 Rec : constant Entity_Id := Scope (C);
7363 Ctyp : constant Entity_Id := Etype (C);
7366 -- If component clause present assume that's the problem
7368 if Present (Component_Clause (C)) then
7369 Error_Msg_Sloc := Sloc (Component_Clause (C));
7370 Error_Msg_N ("\because of Component_Clause#", N);
7374 -- If pragma Pack clause present, assume that's the problem
7376 if Is_Packed (Rec) then
7377 P := Get_Rep_Pragma (Rec, Name_Pack);
7380 Error_Msg_Sloc := Sloc (P);
7381 Error_Msg_N ("\because of pragma Pack#", N);
7386 -- See if record has bad alignment clause
7388 if Has_Alignment_Clause (Rec)
7389 and then Known_Alignment (Rec)
7390 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7392 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
7395 Error_Msg_Sloc := Sloc (P);
7396 Error_Msg_N ("\because of Alignment clause#", N);
7400 -- Couldn't find a reason, so return without a message
7403 end Reason_Bad_Component;
7405 -- Start of processing for Validate_Independence
7408 for J in Independence_Checks.First .. Independence_Checks.Last loop
7409 N := Independence_Checks.Table (J).N;
7410 E := Independence_Checks.Table (J).E;
7411 IC := Pragma_Name (N) = Name_Independent_Components;
7413 -- Deal with component case
7415 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
7416 if not OK_Component (E) then
7418 Reason_Bad_Component (E);
7423 -- Deal with record with Independent_Components
7425 if IC and then Is_Record_Type (E) then
7426 Comp := First_Component_Or_Discriminant (E);
7427 while Present (Comp) loop
7428 if not OK_Component (Comp) then
7430 Reason_Bad_Component (Comp);
7434 Next_Component_Or_Discriminant (Comp);
7438 -- Deal with address clause case
7440 if Is_Object (E) then
7441 Addr := Address_Clause (E);
7443 if Present (Addr) then
7445 Error_Msg_Sloc := Sloc (Addr);
7446 Error_Msg_N ("\because of Address clause#", N);
7451 -- Deal with independent components for array type
7453 if IC and then Is_Array_Type (E) then
7454 Check_Array_Type (E);
7457 -- Deal with independent components for array object
7459 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
7460 Check_Array_Type (Etype (E));
7465 end Validate_Independence;
7467 -----------------------------------
7468 -- Validate_Unchecked_Conversion --
7469 -----------------------------------
7471 procedure Validate_Unchecked_Conversion
7473 Act_Unit : Entity_Id)
7480 -- Obtain source and target types. Note that we call Ancestor_Subtype
7481 -- here because the processing for generic instantiation always makes
7482 -- subtypes, and we want the original frozen actual types.
7484 -- If we are dealing with private types, then do the check on their
7485 -- fully declared counterparts if the full declarations have been
7486 -- encountered (they don't have to be visible, but they must exist!)
7488 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
7490 if Is_Private_Type (Source)
7491 and then Present (Underlying_Type (Source))
7493 Source := Underlying_Type (Source);
7496 Target := Ancestor_Subtype (Etype (Act_Unit));
7498 -- If either type is generic, the instantiation happens within a generic
7499 -- unit, and there is nothing to check. The proper check
7500 -- will happen when the enclosing generic is instantiated.
7502 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
7506 if Is_Private_Type (Target)
7507 and then Present (Underlying_Type (Target))
7509 Target := Underlying_Type (Target);
7512 -- Source may be unconstrained array, but not target
7514 if Is_Array_Type (Target)
7515 and then not Is_Constrained (Target)
7518 ("unchecked conversion to unconstrained array not allowed", N);
7522 -- Warn if conversion between two different convention pointers
7524 if Is_Access_Type (Target)
7525 and then Is_Access_Type (Source)
7526 and then Convention (Target) /= Convention (Source)
7527 and then Warn_On_Unchecked_Conversion
7529 -- Give warnings for subprogram pointers only on most targets. The
7530 -- exception is VMS, where data pointers can have different lengths
7531 -- depending on the pointer convention.
7533 if Is_Access_Subprogram_Type (Target)
7534 or else Is_Access_Subprogram_Type (Source)
7535 or else OpenVMS_On_Target
7538 ("?conversion between pointers with different conventions!", N);
7542 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
7543 -- warning when compiling GNAT-related sources.
7545 if Warn_On_Unchecked_Conversion
7546 and then not In_Predefined_Unit (N)
7547 and then RTU_Loaded (Ada_Calendar)
7549 (Chars (Source) = Name_Time
7551 Chars (Target) = Name_Time)
7553 -- If Ada.Calendar is loaded and the name of one of the operands is
7554 -- Time, there is a good chance that this is Ada.Calendar.Time.
7557 Calendar_Time : constant Entity_Id :=
7558 Full_View (RTE (RO_CA_Time));
7560 pragma Assert (Present (Calendar_Time));
7562 if Source = Calendar_Time
7563 or else Target = Calendar_Time
7566 ("?representation of 'Time values may change between " &
7567 "'G'N'A'T versions", N);
7572 -- Make entry in unchecked conversion table for later processing by
7573 -- Validate_Unchecked_Conversions, which will check sizes and alignments
7574 -- (using values set by the back-end where possible). This is only done
7575 -- if the appropriate warning is active.
7577 if Warn_On_Unchecked_Conversion then
7578 Unchecked_Conversions.Append
7579 (New_Val => UC_Entry'
7584 -- If both sizes are known statically now, then back end annotation
7585 -- is not required to do a proper check but if either size is not
7586 -- known statically, then we need the annotation.
7588 if Known_Static_RM_Size (Source)
7589 and then Known_Static_RM_Size (Target)
7593 Back_Annotate_Rep_Info := True;
7597 -- If unchecked conversion to access type, and access type is declared
7598 -- in the same unit as the unchecked conversion, then set the
7599 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
7602 if Is_Access_Type (Target) and then
7603 In_Same_Source_Unit (Target, N)
7605 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
7608 -- Generate N_Validate_Unchecked_Conversion node for back end in
7609 -- case the back end needs to perform special validation checks.
7611 -- Shouldn't this be in Exp_Ch13, since the check only gets done
7612 -- if we have full expansion and the back end is called ???
7615 Make_Validate_Unchecked_Conversion (Sloc (N));
7616 Set_Source_Type (Vnode, Source);
7617 Set_Target_Type (Vnode, Target);
7619 -- If the unchecked conversion node is in a list, just insert before it.
7620 -- If not we have some strange case, not worth bothering about.
7622 if Is_List_Member (N) then
7623 Insert_After (N, Vnode);
7625 end Validate_Unchecked_Conversion;
7627 ------------------------------------
7628 -- Validate_Unchecked_Conversions --
7629 ------------------------------------
7631 procedure Validate_Unchecked_Conversions is
7633 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
7635 T : UC_Entry renames Unchecked_Conversions.Table (N);
7637 Eloc : constant Source_Ptr := T.Eloc;
7638 Source : constant Entity_Id := T.Source;
7639 Target : constant Entity_Id := T.Target;
7645 -- This validation check, which warns if we have unequal sizes for
7646 -- unchecked conversion, and thus potentially implementation
7647 -- dependent semantics, is one of the few occasions on which we
7648 -- use the official RM size instead of Esize. See description in
7649 -- Einfo "Handling of Type'Size Values" for details.
7651 if Serious_Errors_Detected = 0
7652 and then Known_Static_RM_Size (Source)
7653 and then Known_Static_RM_Size (Target)
7655 -- Don't do the check if warnings off for either type, note the
7656 -- deliberate use of OR here instead of OR ELSE to get the flag
7657 -- Warnings_Off_Used set for both types if appropriate.
7659 and then not (Has_Warnings_Off (Source)
7661 Has_Warnings_Off (Target))
7663 Source_Siz := RM_Size (Source);
7664 Target_Siz := RM_Size (Target);
7666 if Source_Siz /= Target_Siz then
7668 ("?types for unchecked conversion have different sizes!",
7671 if All_Errors_Mode then
7672 Error_Msg_Name_1 := Chars (Source);
7673 Error_Msg_Uint_1 := Source_Siz;
7674 Error_Msg_Name_2 := Chars (Target);
7675 Error_Msg_Uint_2 := Target_Siz;
7676 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
7678 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
7680 if Is_Discrete_Type (Source)
7681 and then Is_Discrete_Type (Target)
7683 if Source_Siz > Target_Siz then
7685 ("\?^ high order bits of source will be ignored!",
7688 elsif Is_Unsigned_Type (Source) then
7690 ("\?source will be extended with ^ high order " &
7691 "zero bits?!", Eloc);
7695 ("\?source will be extended with ^ high order " &
7700 elsif Source_Siz < Target_Siz then
7701 if Is_Discrete_Type (Target) then
7702 if Bytes_Big_Endian then
7704 ("\?target value will include ^ undefined " &
7709 ("\?target value will include ^ undefined " &
7716 ("\?^ trailing bits of target value will be " &
7717 "undefined!", Eloc);
7720 else pragma Assert (Source_Siz > Target_Siz);
7722 ("\?^ trailing bits of source will be ignored!",
7729 -- If both types are access types, we need to check the alignment.
7730 -- If the alignment of both is specified, we can do it here.
7732 if Serious_Errors_Detected = 0
7733 and then Ekind (Source) in Access_Kind
7734 and then Ekind (Target) in Access_Kind
7735 and then Target_Strict_Alignment
7736 and then Present (Designated_Type (Source))
7737 and then Present (Designated_Type (Target))
7740 D_Source : constant Entity_Id := Designated_Type (Source);
7741 D_Target : constant Entity_Id := Designated_Type (Target);
7744 if Known_Alignment (D_Source)
7745 and then Known_Alignment (D_Target)
7748 Source_Align : constant Uint := Alignment (D_Source);
7749 Target_Align : constant Uint := Alignment (D_Target);
7752 if Source_Align < Target_Align
7753 and then not Is_Tagged_Type (D_Source)
7755 -- Suppress warning if warnings suppressed on either
7756 -- type or either designated type. Note the use of
7757 -- OR here instead of OR ELSE. That is intentional,
7758 -- we would like to set flag Warnings_Off_Used in
7759 -- all types for which warnings are suppressed.
7761 and then not (Has_Warnings_Off (D_Source)
7763 Has_Warnings_Off (D_Target)
7765 Has_Warnings_Off (Source)
7767 Has_Warnings_Off (Target))
7769 Error_Msg_Uint_1 := Target_Align;
7770 Error_Msg_Uint_2 := Source_Align;
7771 Error_Msg_Node_1 := D_Target;
7772 Error_Msg_Node_2 := D_Source;
7774 ("?alignment of & (^) is stricter than " &
7775 "alignment of & (^)!", Eloc);
7777 ("\?resulting access value may have invalid " &
7778 "alignment!", Eloc);
7786 end Validate_Unchecked_Conversions;
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