1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Disp; use Exp_Disp;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
43 with Rtsfind; use Rtsfind;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Ch3; use Sem_Ch3;
47 with Sem_Ch6; use Sem_Ch6;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Res; use Sem_Res;
51 with Sem_Type; use Sem_Type;
52 with Sem_Util; use Sem_Util;
53 with Sem_Warn; use Sem_Warn;
54 with Sinput; use Sinput;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Stringt; use Stringt;
59 with Targparm; use Targparm;
60 with Ttypes; use Ttypes;
61 with Tbuild; use Tbuild;
62 with Urealp; use Urealp;
64 with GNAT.Heap_Sort_G;
66 package body Sem_Ch13 is
68 SSU : constant Pos := System_Storage_Unit;
69 -- Convenient short hand for commonly used constant
71 -----------------------
72 -- Local Subprograms --
73 -----------------------
75 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id);
76 -- This routine is called after setting the Esize of type entity Typ.
77 -- The purpose is to deal with the situation where an alignment has been
78 -- inherited from a derived type that is no longer appropriate for the
79 -- new Esize value. In this case, we reset the Alignment to unknown.
81 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
82 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
83 -- then either there are pragma Invariant entries on the rep chain for the
84 -- type (note that Predicate aspects are converted to pragma Predicate), or
85 -- there are inherited aspects from a parent type, or ancestor subtypes.
86 -- This procedure builds the spec and body for the Predicate function that
87 -- tests these predicates. N is the freeze node for the type. The spec of
88 -- the function is inserted before the freeze node, and the body of the
89 -- function is inserted after the freeze node.
91 procedure Build_Static_Predicate
95 -- Given a predicated type Typ, where Typ is a discrete static subtype,
96 -- whose predicate expression is Expr, tests if Expr is a static predicate,
97 -- and if so, builds the predicate range list. Nam is the name of the one
98 -- argument to the predicate function. Occurrences of the type name in the
99 -- predicate expression have been replaced by identifier references to this
100 -- name, which is unique, so any identifier with Chars matching Nam must be
101 -- a reference to the type. If the predicate is non-static, this procedure
102 -- returns doing nothing. If the predicate is static, then the predicate
103 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
104 -- a canonicalized membership operation.
106 function Get_Alignment_Value (Expr : Node_Id) return Uint;
107 -- Given the expression for an alignment value, returns the corresponding
108 -- Uint value. If the value is inappropriate, then error messages are
109 -- posted as required, and a value of No_Uint is returned.
111 function Is_Operational_Item (N : Node_Id) return Boolean;
112 -- A specification for a stream attribute is allowed before the full type
113 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
114 -- that do not specify a representation characteristic are operational
117 procedure New_Stream_Subprogram
121 Nam : TSS_Name_Type);
122 -- Create a subprogram renaming of a given stream attribute to the
123 -- designated subprogram and then in the tagged case, provide this as a
124 -- primitive operation, or in the non-tagged case make an appropriate TSS
125 -- entry. This is more properly an expansion activity than just semantics,
126 -- but the presence of user-defined stream functions for limited types is a
127 -- legality check, which is why this takes place here rather than in
128 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
129 -- function to be generated.
131 -- To avoid elaboration anomalies with freeze nodes, for untagged types
132 -- we generate both a subprogram declaration and a subprogram renaming
133 -- declaration, so that the attribute specification is handled as a
134 -- renaming_as_body. For tagged types, the specification is one of the
138 with procedure Replace_Type_Reference (N : Node_Id);
139 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
140 -- This is used to scan an expression for a predicate or invariant aspect
141 -- replacing occurrences of the name TName (the name of the subtype to
142 -- which the aspect applies) with appropriate references to the parameter
143 -- of the predicate function or invariant procedure. The procedure passed
144 -- as a generic parameter does the actual replacement of node N, which is
145 -- either a simple direct reference to TName, or a selected component that
146 -- represents an appropriately qualified occurrence of TName.
152 Biased : Boolean := True);
153 -- If Biased is True, sets Has_Biased_Representation flag for E, and
154 -- outputs a warning message at node N if Warn_On_Biased_Representation is
155 -- is True. This warning inserts the string Msg to describe the construct
158 ----------------------------------------------
159 -- Table for Validate_Unchecked_Conversions --
160 ----------------------------------------------
162 -- The following table collects unchecked conversions for validation.
163 -- Entries are made by Validate_Unchecked_Conversion and then the
164 -- call to Validate_Unchecked_Conversions does the actual error
165 -- checking and posting of warnings. The reason for this delayed
166 -- processing is to take advantage of back-annotations of size and
167 -- alignment values performed by the back end.
169 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
170 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
171 -- will already have modified all Sloc values if the -gnatD option is set.
173 type UC_Entry is record
174 Eloc : Source_Ptr; -- node used for posting warnings
175 Source : Entity_Id; -- source type for unchecked conversion
176 Target : Entity_Id; -- target type for unchecked conversion
179 package Unchecked_Conversions is new Table.Table (
180 Table_Component_Type => UC_Entry,
181 Table_Index_Type => Int,
182 Table_Low_Bound => 1,
184 Table_Increment => 200,
185 Table_Name => "Unchecked_Conversions");
187 ----------------------------------------
188 -- Table for Validate_Address_Clauses --
189 ----------------------------------------
191 -- If an address clause has the form
193 -- for X'Address use Expr
195 -- where Expr is of the form Y'Address or recursively is a reference
196 -- to a constant of either of these forms, and X and Y are entities of
197 -- objects, then if Y has a smaller alignment than X, that merits a
198 -- warning about possible bad alignment. The following table collects
199 -- address clauses of this kind. We put these in a table so that they
200 -- can be checked after the back end has completed annotation of the
201 -- alignments of objects, since we can catch more cases that way.
203 type Address_Clause_Check_Record is record
205 -- The address clause
208 -- The entity of the object overlaying Y
211 -- The entity of the object being overlaid
214 -- Whether the address is offset within Y
217 package Address_Clause_Checks is new Table.Table (
218 Table_Component_Type => Address_Clause_Check_Record,
219 Table_Index_Type => Int,
220 Table_Low_Bound => 1,
222 Table_Increment => 200,
223 Table_Name => "Address_Clause_Checks");
225 -----------------------------------------
226 -- Adjust_Record_For_Reverse_Bit_Order --
227 -----------------------------------------
229 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
234 -- Processing depends on version of Ada
236 -- For Ada 95, we just renumber bits within a storage unit. We do the
237 -- same for Ada 83 mode, since we recognize pragma Bit_Order in Ada 83,
238 -- and are free to add this extension.
240 if Ada_Version < Ada_2005 then
241 Comp := First_Component_Or_Discriminant (R);
242 while Present (Comp) loop
243 CC := Component_Clause (Comp);
245 -- If component clause is present, then deal with the non-default
246 -- bit order case for Ada 95 mode.
248 -- We only do this processing for the base type, and in fact that
249 -- is important, since otherwise if there are record subtypes, we
250 -- could reverse the bits once for each subtype, which is wrong.
253 and then Ekind (R) = E_Record_Type
256 CFB : constant Uint := Component_Bit_Offset (Comp);
257 CSZ : constant Uint := Esize (Comp);
258 CLC : constant Node_Id := Component_Clause (Comp);
259 Pos : constant Node_Id := Position (CLC);
260 FB : constant Node_Id := First_Bit (CLC);
262 Storage_Unit_Offset : constant Uint :=
263 CFB / System_Storage_Unit;
265 Start_Bit : constant Uint :=
266 CFB mod System_Storage_Unit;
269 -- Cases where field goes over storage unit boundary
271 if Start_Bit + CSZ > System_Storage_Unit then
273 -- Allow multi-byte field but generate warning
275 if Start_Bit mod System_Storage_Unit = 0
276 and then CSZ mod System_Storage_Unit = 0
279 ("multi-byte field specified with non-standard"
280 & " Bit_Order?", CLC);
282 if Bytes_Big_Endian then
284 ("bytes are not reversed "
285 & "(component is big-endian)?", CLC);
288 ("bytes are not reversed "
289 & "(component is little-endian)?", CLC);
292 -- Do not allow non-contiguous field
296 ("attempt to specify non-contiguous field "
297 & "not permitted", CLC);
299 ("\caused by non-standard Bit_Order "
302 ("\consider possibility of using "
303 & "Ada 2005 mode here", CLC);
306 -- Case where field fits in one storage unit
309 -- Give warning if suspicious component clause
311 if Intval (FB) >= System_Storage_Unit
312 and then Warn_On_Reverse_Bit_Order
315 ("?Bit_Order clause does not affect " &
316 "byte ordering", Pos);
318 Intval (Pos) + Intval (FB) /
321 ("?position normalized to ^ before bit " &
322 "order interpreted", Pos);
325 -- Here is where we fix up the Component_Bit_Offset value
326 -- to account for the reverse bit order. Some examples of
327 -- what needs to be done are:
329 -- First_Bit .. Last_Bit Component_Bit_Offset
341 -- The rule is that the first bit is is obtained by
342 -- subtracting the old ending bit from storage_unit - 1.
344 Set_Component_Bit_Offset
346 (Storage_Unit_Offset * System_Storage_Unit) +
347 (System_Storage_Unit - 1) -
348 (Start_Bit + CSZ - 1));
350 Set_Normalized_First_Bit
352 Component_Bit_Offset (Comp) mod
353 System_Storage_Unit);
358 Next_Component_Or_Discriminant (Comp);
361 -- For Ada 2005, we do machine scalar processing, as fully described In
362 -- AI-133. This involves gathering all components which start at the
363 -- same byte offset and processing them together. Same approach is still
364 -- valid in later versions including Ada 2012.
368 Max_Machine_Scalar_Size : constant Uint :=
370 (Standard_Long_Long_Integer_Size);
371 -- We use this as the maximum machine scalar size
374 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
377 -- This first loop through components does two things. First it
378 -- deals with the case of components with component clauses whose
379 -- length is greater than the maximum machine scalar size (either
380 -- accepting them or rejecting as needed). Second, it counts the
381 -- number of components with component clauses whose length does
382 -- not exceed this maximum for later processing.
385 Comp := First_Component_Or_Discriminant (R);
386 while Present (Comp) loop
387 CC := Component_Clause (Comp);
391 Fbit : constant Uint :=
392 Static_Integer (First_Bit (CC));
393 Lbit : constant Uint :=
394 Static_Integer (Last_Bit (CC));
397 -- Case of component with last bit >= max machine scalar
399 if Lbit >= Max_Machine_Scalar_Size then
401 -- This is allowed only if first bit is zero, and
402 -- last bit + 1 is a multiple of storage unit size.
404 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
406 -- This is the case to give a warning if enabled
408 if Warn_On_Reverse_Bit_Order then
410 ("multi-byte field specified with "
411 & " non-standard Bit_Order?", CC);
413 if Bytes_Big_Endian then
415 ("\bytes are not reversed "
416 & "(component is big-endian)?", CC);
419 ("\bytes are not reversed "
420 & "(component is little-endian)?", CC);
424 -- Give error message for RM 13.4.1(10) violation
428 ("machine scalar rules not followed for&",
429 First_Bit (CC), Comp);
431 Error_Msg_Uint_1 := Lbit;
432 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
434 ("\last bit (^) exceeds maximum machine "
438 if (Lbit + 1) mod SSU /= 0 then
439 Error_Msg_Uint_1 := SSU;
441 ("\and is not a multiple of Storage_Unit (^) "
442 & "('R'M 13.4.1(10))",
446 Error_Msg_Uint_1 := Fbit;
448 ("\and first bit (^) is non-zero "
449 & "('R'M 13.4.1(10))",
454 -- OK case of machine scalar related component clause,
455 -- For now, just count them.
458 Num_CC := Num_CC + 1;
463 Next_Component_Or_Discriminant (Comp);
466 -- We need to sort the component clauses on the basis of the
467 -- Position values in the clause, so we can group clauses with
468 -- the same Position. together to determine the relevant machine
472 Comps : array (0 .. Num_CC) of Entity_Id;
473 -- Array to collect component and discriminant entities. The
474 -- data starts at index 1, the 0'th entry is for the sort
477 function CP_Lt (Op1, Op2 : Natural) return Boolean;
478 -- Compare routine for Sort
480 procedure CP_Move (From : Natural; To : Natural);
481 -- Move routine for Sort
483 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
487 -- Start and stop positions in the component list of the set of
488 -- components with the same starting position (that constitute
489 -- components in a single machine scalar).
492 -- Maximum last bit value of any component in this set
495 -- Corresponding machine scalar size
501 function CP_Lt (Op1, Op2 : Natural) return Boolean is
503 return Position (Component_Clause (Comps (Op1))) <
504 Position (Component_Clause (Comps (Op2)));
511 procedure CP_Move (From : Natural; To : Natural) is
513 Comps (To) := Comps (From);
516 -- Start of processing for Sort_CC
519 -- Collect the machine scalar relevant component clauses
522 Comp := First_Component_Or_Discriminant (R);
523 while Present (Comp) loop
525 CC : constant Node_Id := Component_Clause (Comp);
528 -- Collect only component clauses whose last bit is less
529 -- than machine scalar size. Any component clause whose
530 -- last bit exceeds this value does not take part in
531 -- machine scalar layout considerations. The test for
532 -- Error_Posted makes sure we exclude component clauses
533 -- for which we already posted an error.
536 and then not Error_Posted (Last_Bit (CC))
537 and then Static_Integer (Last_Bit (CC)) <
538 Max_Machine_Scalar_Size
540 Num_CC := Num_CC + 1;
541 Comps (Num_CC) := Comp;
545 Next_Component_Or_Discriminant (Comp);
548 -- Sort by ascending position number
550 Sorting.Sort (Num_CC);
552 -- We now have all the components whose size does not exceed
553 -- the max machine scalar value, sorted by starting position.
554 -- In this loop we gather groups of clauses starting at the
555 -- same position, to process them in accordance with AI-133.
558 while Stop < Num_CC loop
563 (Last_Bit (Component_Clause (Comps (Start))));
564 while Stop < Num_CC loop
566 (Position (Component_Clause (Comps (Stop + 1)))) =
568 (Position (Component_Clause (Comps (Stop))))
576 (Component_Clause (Comps (Stop)))));
582 -- Now we have a group of component clauses from Start to
583 -- Stop whose positions are identical, and MaxL is the
584 -- maximum last bit value of any of these components.
586 -- We need to determine the corresponding machine scalar
587 -- size. This loop assumes that machine scalar sizes are
588 -- even, and that each possible machine scalar has twice
589 -- as many bits as the next smaller one.
591 MSS := Max_Machine_Scalar_Size;
593 and then (MSS / 2) >= SSU
594 and then (MSS / 2) > MaxL
599 -- Here is where we fix up the Component_Bit_Offset value
600 -- to account for the reverse bit order. Some examples of
601 -- what needs to be done for the case of a machine scalar
604 -- First_Bit .. Last_Bit Component_Bit_Offset
616 -- The rule is that the first bit is obtained by subtracting
617 -- the old ending bit from machine scalar size - 1.
619 for C in Start .. Stop loop
621 Comp : constant Entity_Id := Comps (C);
622 CC : constant Node_Id :=
623 Component_Clause (Comp);
624 LB : constant Uint :=
625 Static_Integer (Last_Bit (CC));
626 NFB : constant Uint := MSS - Uint_1 - LB;
627 NLB : constant Uint := NFB + Esize (Comp) - 1;
628 Pos : constant Uint :=
629 Static_Integer (Position (CC));
632 if Warn_On_Reverse_Bit_Order then
633 Error_Msg_Uint_1 := MSS;
635 ("info: reverse bit order in machine " &
636 "scalar of length^?", First_Bit (CC));
637 Error_Msg_Uint_1 := NFB;
638 Error_Msg_Uint_2 := NLB;
640 if Bytes_Big_Endian then
642 ("?\info: big-endian range for "
643 & "component & is ^ .. ^",
644 First_Bit (CC), Comp);
647 ("?\info: little-endian range "
648 & "for component & is ^ .. ^",
649 First_Bit (CC), Comp);
653 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
654 Set_Normalized_First_Bit (Comp, NFB mod SSU);
661 end Adjust_Record_For_Reverse_Bit_Order;
663 --------------------------------------
664 -- Alignment_Check_For_Esize_Change --
665 --------------------------------------
667 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id) is
669 -- If the alignment is known, and not set by a rep clause, and is
670 -- inconsistent with the size being set, then reset it to unknown,
671 -- we assume in this case that the size overrides the inherited
672 -- alignment, and that the alignment must be recomputed.
674 if Known_Alignment (Typ)
675 and then not Has_Alignment_Clause (Typ)
676 and then Esize (Typ) mod (Alignment (Typ) * SSU) /= 0
678 Init_Alignment (Typ);
680 end Alignment_Check_For_Esize_Change;
682 -----------------------------------
683 -- Analyze_Aspect_Specifications --
684 -----------------------------------
686 procedure Analyze_Aspect_Specifications
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 attach the corresponding pragma/attribute definition
704 -- clause to the aspect specification node, which is then placed in the
705 -- Rep Item chain. In this case we mark the entity by setting the flag
706 -- Has_Delayed_Aspects and we evaluate the rep item at the freeze point.
708 -- If no delay is required, we just insert the pragma or attribute
709 -- after the declaration, and it will get processed by the normal
710 -- circuit. The From_Aspect_Specification flag is set on the pragma
711 -- or attribute definition node in either case to activate special
712 -- processing (e.g. not traversing the list of homonyms for inline).
714 Delay_Required : Boolean;
715 -- Set True if delay is required
718 -- Return if no aspects
724 -- Loop through aspects
727 while Present (Aspect) loop
729 Loc : constant Source_Ptr := Sloc (Aspect);
730 Id : constant Node_Id := Identifier (Aspect);
731 Expr : constant Node_Id := Expression (Aspect);
732 Nam : constant Name_Id := Chars (Id);
733 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
736 Eloc : Source_Ptr := Sloc (Expr);
737 -- Source location of expression, modified when we split PPC's
740 -- Skip aspect if already analyzed (not clear if this is needed)
742 if Analyzed (Aspect) then
746 Set_Analyzed (Aspect);
747 Set_Entity (Aspect, E);
748 Ent := New_Occurrence_Of (E, Sloc (Id));
750 -- Check for duplicate aspect. Note that the Comes_From_Source
751 -- test allows duplicate Pre/Post's that we generate internally
752 -- to escape being flagged here.
755 while Anod /= Aspect loop
756 if Same_Aspect (A_Id, Get_Aspect_Id (Chars (Identifier (Anod))))
757 and then Comes_From_Source (Aspect)
759 Error_Msg_Name_1 := Nam;
760 Error_Msg_Sloc := Sloc (Anod);
762 -- Case of same aspect specified twice
764 if Class_Present (Anod) = Class_Present (Aspect) then
765 if not Class_Present (Anod) then
767 ("aspect% for & previously given#",
771 ("aspect `%''Class` for & previously given#",
775 -- Case of Pre and Pre'Class both specified
777 elsif Nam = Name_Pre then
778 if Class_Present (Aspect) then
780 ("aspect `Pre''Class` for & is not allowed here",
783 ("\since aspect `Pre` previously given#",
788 ("aspect `Pre` for & is not allowed here",
791 ("\since aspect `Pre''Class` previously given#",
802 -- Copy expression for later processing by the procedures
803 -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations]
805 Set_Entity (Id, New_Copy_Tree (Expr));
807 -- Processing based on specific aspect
811 -- No_Aspect should be impossible
816 -- Aspects taking an optional boolean argument. For all of
817 -- these we just create a matching pragma and insert it. When
818 -- the aspect is processed to insert the pragma, the expression
819 -- is analyzed, setting Cancel_Aspect if the value is False.
821 when Boolean_Aspects =>
822 Set_Is_Boolean_Aspect (Aspect);
824 -- Build corresponding pragma node
828 Pragma_Argument_Associations => New_List (Ent),
830 Make_Identifier (Sloc (Id), Chars (Id)));
832 -- No delay required if no expression (nothing to delay!)
835 Delay_Required := False;
837 -- Expression is present, delay is required. Note that
838 -- even if the expression is "True", some idiot might
839 -- define True as False before the freeze point!
842 Delay_Required := True;
843 Set_Is_Delayed_Aspect (Aspect);
846 -- Aspects corresponding to attribute definition clauses
848 when Aspect_Address |
851 Aspect_Component_Size |
852 Aspect_External_Tag |
854 Aspect_Machine_Radix |
859 Aspect_Storage_Pool |
860 Aspect_Storage_Size |
865 -- Construct the attribute definition clause
868 Make_Attribute_Definition_Clause (Loc,
871 Expression => Relocate_Node (Expr));
873 -- A delay is required except in the common case where
874 -- the expression is a literal, in which case it is fine
875 -- to take care of it right away.
877 if Nkind_In (Expr, N_Integer_Literal, N_String_Literal) then
878 Delay_Required := False;
880 Delay_Required := True;
881 Set_Is_Delayed_Aspect (Aspect);
884 -- Aspects corresponding to pragmas with two arguments, where
885 -- the first argument is a local name referring to the entity,
886 -- and the second argument is the aspect definition expression.
888 when Aspect_Suppress |
891 -- Construct the pragma
895 Pragma_Argument_Associations => New_List (
896 New_Occurrence_Of (E, Eloc),
897 Relocate_Node (Expr)),
899 Make_Identifier (Sloc (Id), Chars (Id)));
901 -- We don't have to play the delay game here, since the only
902 -- values are check names which don't get analyzed anyway.
904 Delay_Required := False;
906 -- Aspects corresponding to pragmas with two arguments, where
907 -- the second argument is a local name referring to the entity,
908 -- and the first argument is the aspect definition expression.
910 when Aspect_Warnings =>
912 -- Construct the pragma
916 Pragma_Argument_Associations => New_List (
917 Relocate_Node (Expr),
918 New_Occurrence_Of (E, Eloc)),
920 Make_Identifier (Sloc (Id), Chars (Id)),
921 Class_Present => Class_Present (Aspect));
923 -- We don't have to play the delay game here, since the only
924 -- values are ON/OFF which don't get analyzed anyway.
926 Delay_Required := False;
928 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
929 -- with a first argument that is the expression, and a second
930 -- argument that is an informative message if the test fails.
931 -- This is inserted right after the declaration, to get the
932 -- required pragma placement. The processing for the pragmas
933 -- takes care of the required delay.
936 Aspect_Precondition |
938 Aspect_Postcondition =>
943 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
944 Pname := Name_Precondition;
946 Pname := Name_Postcondition;
949 -- If the expressions is of the form A and then B, then
950 -- we generate separate Pre/Post aspects for the separate
951 -- clauses. Since we allow multiple pragmas, there is no
952 -- problem in allowing multiple Pre/Post aspects internally.
954 -- We do not do this for Pre'Class, since we have to put
955 -- these conditions together in a complex OR expression
957 if Pname = Name_Postcondition
958 or else not Class_Present (Aspect)
960 while Nkind (Expr) = N_And_Then loop
961 Insert_After (Aspect,
962 Make_Aspect_Specification (Sloc (Right_Opnd (Expr)),
963 Identifier => Identifier (Aspect),
964 Expression => Relocate_Node (Right_Opnd (Expr)),
965 Class_Present => Class_Present (Aspect),
967 Rewrite (Expr, Relocate_Node (Left_Opnd (Expr)));
972 -- Build the precondition/postcondition pragma
977 Make_Identifier (Sloc (Id), Pname),
978 Class_Present => Class_Present (Aspect),
979 Split_PPC => Split_PPC (Aspect),
980 Pragma_Argument_Associations => New_List (
981 Make_Pragma_Argument_Association (Eloc,
983 Expression => Relocate_Node (Expr))));
985 -- Add message unless exception messages are suppressed
987 if not Opt.Exception_Locations_Suppressed then
988 Append_To (Pragma_Argument_Associations (Aitem),
989 Make_Pragma_Argument_Association (Eloc,
990 Chars => Name_Message,
992 Make_String_Literal (Eloc,
994 & Get_Name_String (Pname)
996 & Build_Location_String (Eloc))));
999 Set_From_Aspect_Specification (Aitem, True);
1000 Set_Is_Delayed_Aspect (Aspect);
1002 -- For Pre/Post cases, insert immediately after the entity
1003 -- declaration, since that is the required pragma placement.
1004 -- Note that for these aspects, we do not have to worry
1005 -- about delay issues, since the pragmas themselves deal
1006 -- with delay of visibility for the expression analysis.
1008 -- If the entity is a library-level subprogram, the pre/
1009 -- postconditions must be treated as late pragmas.
1011 if Nkind (Parent (N)) = N_Compilation_Unit then
1012 Add_Global_Declaration (Aitem);
1014 Insert_After (N, Aitem);
1020 -- Invariant aspects generate a corresponding pragma with a
1021 -- first argument that is the entity, a second argument that is
1022 -- the expression and a third argument that is an appropriate
1023 -- message. This is inserted right after the declaration, to
1024 -- get the required pragma placement. The pragma processing
1025 -- takes care of the required delay.
1027 when Aspect_Invariant |
1028 Aspect_Type_Invariant =>
1030 -- Construct the pragma
1034 Pragma_Argument_Associations =>
1035 New_List (Ent, Relocate_Node (Expr)),
1036 Class_Present => Class_Present (Aspect),
1037 Pragma_Identifier =>
1038 Make_Identifier (Sloc (Id), Name_Invariant));
1040 -- Add message unless exception messages are suppressed
1042 if not Opt.Exception_Locations_Suppressed then
1043 Append_To (Pragma_Argument_Associations (Aitem),
1044 Make_Pragma_Argument_Association (Eloc,
1045 Chars => Name_Message,
1047 Make_String_Literal (Eloc,
1048 Strval => "failed invariant from "
1049 & Build_Location_String (Eloc))));
1052 Set_From_Aspect_Specification (Aitem, True);
1053 Set_Is_Delayed_Aspect (Aspect);
1055 -- For Invariant case, insert immediately after the entity
1056 -- declaration. We do not have to worry about delay issues
1057 -- since the pragma processing takes care of this.
1059 Insert_After (N, Aitem);
1062 -- Predicate aspects generate a corresponding pragma with a
1063 -- first argument that is the entity, and the second argument
1064 -- is the expression.
1066 when Aspect_Dynamic_Predicate |
1068 Aspect_Static_Predicate =>
1070 -- Construct the pragma (always a pragma Predicate, with
1071 -- flags recording whether
1075 Pragma_Argument_Associations =>
1076 New_List (Ent, Relocate_Node (Expr)),
1077 Class_Present => Class_Present (Aspect),
1078 Pragma_Identifier =>
1079 Make_Identifier (Sloc (Id), Name_Predicate));
1081 Set_From_Aspect_Specification (Aitem, True);
1083 -- Set special flags for dynamic/static cases
1085 if A_Id = Aspect_Dynamic_Predicate then
1086 Set_From_Dynamic_Predicate (Aitem);
1087 elsif A_Id = Aspect_Static_Predicate then
1088 Set_From_Static_Predicate (Aitem);
1091 -- Make sure we have a freeze node (it might otherwise be
1092 -- missing in cases like subtype X is Y, and we would not
1093 -- have a place to build the predicate function).
1095 Set_Has_Predicates (E);
1096 Ensure_Freeze_Node (E);
1097 Set_Is_Delayed_Aspect (Aspect);
1098 Delay_Required := True;
1101 Set_From_Aspect_Specification (Aitem, True);
1103 -- If a delay is required, we delay the freeze (not much point in
1104 -- delaying the aspect if we don't delay the freeze!). The pragma
1105 -- or clause is then attached to the aspect specification which
1106 -- is placed in the rep item list.
1108 if Delay_Required then
1109 Ensure_Freeze_Node (E);
1110 Set_Is_Delayed_Aspect (Aitem);
1111 Set_Has_Delayed_Aspects (E);
1112 Set_Aspect_Rep_Item (Aspect, Aitem);
1113 Record_Rep_Item (E, Aspect);
1115 -- If no delay required, insert the pragma/clause in the tree
1118 -- For Pre/Post cases, insert immediately after the entity
1119 -- declaration, since that is the required pragma placement.
1121 if A_Id = Aspect_Pre or else
1122 A_Id = Aspect_Post or else
1123 A_Id = Aspect_Precondition or else
1124 A_Id = Aspect_Postcondition
1126 Insert_After (N, Aitem);
1128 -- For all other cases, insert in sequence
1131 Insert_After (Ins_Node, Aitem);
1140 end Analyze_Aspect_Specifications;
1142 -----------------------
1143 -- Analyze_At_Clause --
1144 -----------------------
1146 -- An at clause is replaced by the corresponding Address attribute
1147 -- definition clause that is the preferred approach in Ada 95.
1149 procedure Analyze_At_Clause (N : Node_Id) is
1150 CS : constant Boolean := Comes_From_Source (N);
1153 -- This is an obsolescent feature
1155 Check_Restriction (No_Obsolescent_Features, N);
1157 if Warn_On_Obsolescent_Feature then
1159 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1161 ("\use address attribute definition clause instead?", N);
1164 -- Rewrite as address clause
1167 Make_Attribute_Definition_Clause (Sloc (N),
1168 Name => Identifier (N),
1169 Chars => Name_Address,
1170 Expression => Expression (N)));
1172 -- We preserve Comes_From_Source, since logically the clause still
1173 -- comes from the source program even though it is changed in form.
1175 Set_Comes_From_Source (N, CS);
1177 -- Analyze rewritten clause
1179 Analyze_Attribute_Definition_Clause (N);
1180 end Analyze_At_Clause;
1182 -----------------------------------------
1183 -- Analyze_Attribute_Definition_Clause --
1184 -----------------------------------------
1186 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1187 Loc : constant Source_Ptr := Sloc (N);
1188 Nam : constant Node_Id := Name (N);
1189 Attr : constant Name_Id := Chars (N);
1190 Expr : constant Node_Id := Expression (N);
1191 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1195 FOnly : Boolean := False;
1196 -- Reset to True for subtype specific attribute (Alignment, Size)
1197 -- and for stream attributes, i.e. those cases where in the call
1198 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1199 -- rules are checked. Note that the case of stream attributes is not
1200 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1201 -- disallow Storage_Size for derived task types, but that is also
1202 -- clearly unintentional.
1204 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1205 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1206 -- definition clauses.
1208 function Duplicate_Clause return Boolean;
1209 -- This routine checks if the aspect for U_Ent being given by attribute
1210 -- definition clause N is for an aspect that has already been specified,
1211 -- and if so gives an error message. If there is a duplicate, True is
1212 -- returned, otherwise if there is no error, False is returned.
1214 -----------------------------------
1215 -- Analyze_Stream_TSS_Definition --
1216 -----------------------------------
1218 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1219 Subp : Entity_Id := Empty;
1224 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1226 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1227 -- Return true if the entity is a subprogram with an appropriate
1228 -- profile for the attribute being defined.
1230 ----------------------
1231 -- Has_Good_Profile --
1232 ----------------------
1234 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1236 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1237 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1238 (False => E_Procedure, True => E_Function);
1242 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1246 F := First_Formal (Subp);
1249 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1250 or else Designated_Type (Etype (F)) /=
1251 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1256 if not Is_Function then
1260 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1261 (False => E_In_Parameter,
1262 True => E_Out_Parameter);
1264 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1272 Typ := Etype (Subp);
1275 return Base_Type (Typ) = Base_Type (Ent)
1276 and then No (Next_Formal (F));
1277 end Has_Good_Profile;
1279 -- Start of processing for Analyze_Stream_TSS_Definition
1284 if not Is_Type (U_Ent) then
1285 Error_Msg_N ("local name must be a subtype", Nam);
1289 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1291 -- If Pnam is present, it can be either inherited from an ancestor
1292 -- type (in which case it is legal to redefine it for this type), or
1293 -- be a previous definition of the attribute for the same type (in
1294 -- which case it is illegal).
1296 -- In the first case, it will have been analyzed already, and we
1297 -- can check that its profile does not match the expected profile
1298 -- for a stream attribute of U_Ent. In the second case, either Pnam
1299 -- has been analyzed (and has the expected profile), or it has not
1300 -- been analyzed yet (case of a type that has not been frozen yet
1301 -- and for which the stream attribute has been set using Set_TSS).
1304 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1306 Error_Msg_Sloc := Sloc (Pnam);
1307 Error_Msg_Name_1 := Attr;
1308 Error_Msg_N ("% attribute already defined #", Nam);
1314 if Is_Entity_Name (Expr) then
1315 if not Is_Overloaded (Expr) then
1316 if Has_Good_Profile (Entity (Expr)) then
1317 Subp := Entity (Expr);
1321 Get_First_Interp (Expr, I, It);
1322 while Present (It.Nam) loop
1323 if Has_Good_Profile (It.Nam) then
1328 Get_Next_Interp (I, It);
1333 if Present (Subp) then
1334 if Is_Abstract_Subprogram (Subp) then
1335 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1339 Set_Entity (Expr, Subp);
1340 Set_Etype (Expr, Etype (Subp));
1342 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1345 Error_Msg_Name_1 := Attr;
1346 Error_Msg_N ("incorrect expression for% attribute", Expr);
1348 end Analyze_Stream_TSS_Definition;
1350 ----------------------
1351 -- Duplicate_Clause --
1352 ----------------------
1354 function Duplicate_Clause return Boolean is
1358 -- Nothing to do if this attribute definition clause comes from
1359 -- an aspect specification, since we could not be duplicating an
1360 -- explicit clause, and we dealt with the case of duplicated aspects
1361 -- in Analyze_Aspect_Specifications.
1363 if From_Aspect_Specification (N) then
1367 -- Otherwise current clause may duplicate previous clause or a
1368 -- previously given aspect specification for the same aspect.
1370 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
1373 if Entity (A) = U_Ent then
1374 Error_Msg_Name_1 := Chars (N);
1375 Error_Msg_Sloc := Sloc (A);
1376 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
1382 end Duplicate_Clause;
1384 -- Start of processing for Analyze_Attribute_Definition_Clause
1387 -- Process Ignore_Rep_Clauses option
1389 if Ignore_Rep_Clauses then
1392 -- The following should be ignored. They do not affect legality
1393 -- and may be target dependent. The basic idea of -gnatI is to
1394 -- ignore any rep clauses that may be target dependent but do not
1395 -- affect legality (except possibly to be rejected because they
1396 -- are incompatible with the compilation target).
1398 when Attribute_Alignment |
1399 Attribute_Bit_Order |
1400 Attribute_Component_Size |
1401 Attribute_Machine_Radix |
1402 Attribute_Object_Size |
1405 Attribute_Stream_Size |
1406 Attribute_Value_Size =>
1408 Rewrite (N, Make_Null_Statement (Sloc (N)));
1411 -- The following should not be ignored, because in the first place
1412 -- they are reasonably portable, and should not cause problems in
1413 -- compiling code from another target, and also they do affect
1414 -- legality, e.g. failing to provide a stream attribute for a
1415 -- type may make a program illegal.
1417 when Attribute_External_Tag |
1421 Attribute_Storage_Pool |
1422 Attribute_Storage_Size |
1426 -- Other cases are errors ("attribute& cannot be set with
1427 -- definition clause"), which will be caught below.
1435 Ent := Entity (Nam);
1437 if Rep_Item_Too_Early (Ent, N) then
1441 -- Rep clause applies to full view of incomplete type or private type if
1442 -- we have one (if not, this is a premature use of the type). However,
1443 -- certain semantic checks need to be done on the specified entity (i.e.
1444 -- the private view), so we save it in Ent.
1446 if Is_Private_Type (Ent)
1447 and then Is_Derived_Type (Ent)
1448 and then not Is_Tagged_Type (Ent)
1449 and then No (Full_View (Ent))
1451 -- If this is a private type whose completion is a derivation from
1452 -- another private type, there is no full view, and the attribute
1453 -- belongs to the type itself, not its underlying parent.
1457 elsif Ekind (Ent) = E_Incomplete_Type then
1459 -- The attribute applies to the full view, set the entity of the
1460 -- attribute definition accordingly.
1462 Ent := Underlying_Type (Ent);
1464 Set_Entity (Nam, Ent);
1467 U_Ent := Underlying_Type (Ent);
1470 -- Complete other routine error checks
1472 if Etype (Nam) = Any_Type then
1475 elsif Scope (Ent) /= Current_Scope then
1476 Error_Msg_N ("entity must be declared in this scope", Nam);
1479 elsif No (U_Ent) then
1482 elsif Is_Type (U_Ent)
1483 and then not Is_First_Subtype (U_Ent)
1484 and then Id /= Attribute_Object_Size
1485 and then Id /= Attribute_Value_Size
1486 and then not From_At_Mod (N)
1488 Error_Msg_N ("cannot specify attribute for subtype", Nam);
1492 Set_Entity (N, U_Ent);
1494 -- Switch on particular attribute
1502 -- Address attribute definition clause
1504 when Attribute_Address => Address : begin
1506 -- A little error check, catch for X'Address use X'Address;
1508 if Nkind (Nam) = N_Identifier
1509 and then Nkind (Expr) = N_Attribute_Reference
1510 and then Attribute_Name (Expr) = Name_Address
1511 and then Nkind (Prefix (Expr)) = N_Identifier
1512 and then Chars (Nam) = Chars (Prefix (Expr))
1515 ("address for & is self-referencing", Prefix (Expr), Ent);
1519 -- Not that special case, carry on with analysis of expression
1521 Analyze_And_Resolve (Expr, RTE (RE_Address));
1523 -- Even when ignoring rep clauses we need to indicate that the
1524 -- entity has an address clause and thus it is legal to declare
1527 if Ignore_Rep_Clauses then
1528 if Ekind_In (U_Ent, E_Variable, E_Constant) then
1529 Record_Rep_Item (U_Ent, N);
1535 if Duplicate_Clause then
1538 -- Case of address clause for subprogram
1540 elsif Is_Subprogram (U_Ent) then
1541 if Has_Homonym (U_Ent) then
1543 ("address clause cannot be given " &
1544 "for overloaded subprogram",
1549 -- For subprograms, all address clauses are permitted, and we
1550 -- mark the subprogram as having a deferred freeze so that Gigi
1551 -- will not elaborate it too soon.
1553 -- Above needs more comments, what is too soon about???
1555 Set_Has_Delayed_Freeze (U_Ent);
1557 -- Case of address clause for entry
1559 elsif Ekind (U_Ent) = E_Entry then
1560 if Nkind (Parent (N)) = N_Task_Body then
1562 ("entry address must be specified in task spec", Nam);
1566 -- For entries, we require a constant address
1568 Check_Constant_Address_Clause (Expr, U_Ent);
1570 -- Special checks for task types
1572 if Is_Task_Type (Scope (U_Ent))
1573 and then Comes_From_Source (Scope (U_Ent))
1576 ("?entry address declared for entry in task type", N);
1578 ("\?only one task can be declared of this type", N);
1581 -- Entry address clauses are obsolescent
1583 Check_Restriction (No_Obsolescent_Features, N);
1585 if Warn_On_Obsolescent_Feature then
1587 ("attaching interrupt to task entry is an " &
1588 "obsolescent feature (RM J.7.1)?", N);
1590 ("\use interrupt procedure instead?", N);
1593 -- Case of an address clause for a controlled object which we
1594 -- consider to be erroneous.
1596 elsif Is_Controlled (Etype (U_Ent))
1597 or else Has_Controlled_Component (Etype (U_Ent))
1600 ("?controlled object& must not be overlaid", Nam, U_Ent);
1602 ("\?Program_Error will be raised at run time", Nam);
1603 Insert_Action (Declaration_Node (U_Ent),
1604 Make_Raise_Program_Error (Loc,
1605 Reason => PE_Overlaid_Controlled_Object));
1608 -- Case of address clause for a (non-controlled) object
1611 Ekind (U_Ent) = E_Variable
1613 Ekind (U_Ent) = E_Constant
1616 Expr : constant Node_Id := Expression (N);
1621 -- Exported variables cannot have an address clause, because
1622 -- this cancels the effect of the pragma Export.
1624 if Is_Exported (U_Ent) then
1626 ("cannot export object with address clause", Nam);
1630 Find_Overlaid_Entity (N, O_Ent, Off);
1632 -- Overlaying controlled objects is erroneous
1635 and then (Has_Controlled_Component (Etype (O_Ent))
1636 or else Is_Controlled (Etype (O_Ent)))
1639 ("?cannot overlay with controlled object", Expr);
1641 ("\?Program_Error will be raised at run time", Expr);
1642 Insert_Action (Declaration_Node (U_Ent),
1643 Make_Raise_Program_Error (Loc,
1644 Reason => PE_Overlaid_Controlled_Object));
1647 elsif Present (O_Ent)
1648 and then Ekind (U_Ent) = E_Constant
1649 and then not Is_Constant_Object (O_Ent)
1651 Error_Msg_N ("constant overlays a variable?", Expr);
1653 elsif Present (Renamed_Object (U_Ent)) then
1655 ("address clause not allowed"
1656 & " for a renaming declaration (RM 13.1(6))", Nam);
1659 -- Imported variables can have an address clause, but then
1660 -- the import is pretty meaningless except to suppress
1661 -- initializations, so we do not need such variables to
1662 -- be statically allocated (and in fact it causes trouble
1663 -- if the address clause is a local value).
1665 elsif Is_Imported (U_Ent) then
1666 Set_Is_Statically_Allocated (U_Ent, False);
1669 -- We mark a possible modification of a variable with an
1670 -- address clause, since it is likely aliasing is occurring.
1672 Note_Possible_Modification (Nam, Sure => False);
1674 -- Here we are checking for explicit overlap of one variable
1675 -- by another, and if we find this then mark the overlapped
1676 -- variable as also being volatile to prevent unwanted
1677 -- optimizations. This is a significant pessimization so
1678 -- avoid it when there is an offset, i.e. when the object
1679 -- is composite; they cannot be optimized easily anyway.
1682 and then Is_Object (O_Ent)
1685 Set_Treat_As_Volatile (O_Ent);
1688 -- Legality checks on the address clause for initialized
1689 -- objects is deferred until the freeze point, because
1690 -- a subsequent pragma might indicate that the object is
1691 -- imported and thus not initialized.
1693 Set_Has_Delayed_Freeze (U_Ent);
1695 -- If an initialization call has been generated for this
1696 -- object, it needs to be deferred to after the freeze node
1697 -- we have just now added, otherwise GIGI will see a
1698 -- reference to the variable (as actual to the IP call)
1699 -- before its definition.
1702 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
1704 if Present (Init_Call) then
1706 Append_Freeze_Action (U_Ent, Init_Call);
1710 if Is_Exported (U_Ent) then
1712 ("& cannot be exported if an address clause is given",
1715 ("\define and export a variable " &
1716 "that holds its address instead",
1720 -- Entity has delayed freeze, so we will generate an
1721 -- alignment check at the freeze point unless suppressed.
1723 if not Range_Checks_Suppressed (U_Ent)
1724 and then not Alignment_Checks_Suppressed (U_Ent)
1726 Set_Check_Address_Alignment (N);
1729 -- Kill the size check code, since we are not allocating
1730 -- the variable, it is somewhere else.
1732 Kill_Size_Check_Code (U_Ent);
1734 -- If the address clause is of the form:
1736 -- for Y'Address use X'Address
1740 -- Const : constant Address := X'Address;
1742 -- for Y'Address use Const;
1744 -- then we make an entry in the table for checking the size
1745 -- and alignment of the overlaying variable. We defer this
1746 -- check till after code generation to take full advantage
1747 -- of the annotation done by the back end. This entry is
1748 -- only made if the address clause comes from source.
1749 -- If the entity has a generic type, the check will be
1750 -- performed in the instance if the actual type justifies
1751 -- it, and we do not insert the clause in the table to
1752 -- prevent spurious warnings.
1754 if Address_Clause_Overlay_Warnings
1755 and then Comes_From_Source (N)
1756 and then Present (O_Ent)
1757 and then Is_Object (O_Ent)
1759 if not Is_Generic_Type (Etype (U_Ent)) then
1760 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
1763 -- If variable overlays a constant view, and we are
1764 -- warning on overlays, then mark the variable as
1765 -- overlaying a constant (we will give warnings later
1766 -- if this variable is assigned).
1768 if Is_Constant_Object (O_Ent)
1769 and then Ekind (U_Ent) = E_Variable
1771 Set_Overlays_Constant (U_Ent);
1776 -- Not a valid entity for an address clause
1779 Error_Msg_N ("address cannot be given for &", Nam);
1787 -- Alignment attribute definition clause
1789 when Attribute_Alignment => Alignment : declare
1790 Align : constant Uint := Get_Alignment_Value (Expr);
1795 if not Is_Type (U_Ent)
1796 and then Ekind (U_Ent) /= E_Variable
1797 and then Ekind (U_Ent) /= E_Constant
1799 Error_Msg_N ("alignment cannot be given for &", Nam);
1801 elsif Duplicate_Clause then
1804 elsif Align /= No_Uint then
1805 Set_Has_Alignment_Clause (U_Ent);
1806 Set_Alignment (U_Ent, Align);
1808 -- For an array type, U_Ent is the first subtype. In that case,
1809 -- also set the alignment of the anonymous base type so that
1810 -- other subtypes (such as the itypes for aggregates of the
1811 -- type) also receive the expected alignment.
1813 if Is_Array_Type (U_Ent) then
1814 Set_Alignment (Base_Type (U_Ent), Align);
1823 -- Bit_Order attribute definition clause
1825 when Attribute_Bit_Order => Bit_Order : declare
1827 if not Is_Record_Type (U_Ent) then
1829 ("Bit_Order can only be defined for record type", Nam);
1831 elsif Duplicate_Clause then
1835 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
1837 if Etype (Expr) = Any_Type then
1840 elsif not Is_Static_Expression (Expr) then
1841 Flag_Non_Static_Expr
1842 ("Bit_Order requires static expression!", Expr);
1845 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
1846 Set_Reverse_Bit_Order (U_Ent, True);
1852 --------------------
1853 -- Component_Size --
1854 --------------------
1856 -- Component_Size attribute definition clause
1858 when Attribute_Component_Size => Component_Size_Case : declare
1859 Csize : constant Uint := Static_Integer (Expr);
1863 New_Ctyp : Entity_Id;
1867 if not Is_Array_Type (U_Ent) then
1868 Error_Msg_N ("component size requires array type", Nam);
1872 Btype := Base_Type (U_Ent);
1873 Ctyp := Component_Type (Btype);
1875 if Duplicate_Clause then
1878 elsif Rep_Item_Too_Early (Btype, N) then
1881 elsif Csize /= No_Uint then
1882 Check_Size (Expr, Ctyp, Csize, Biased);
1884 -- For the biased case, build a declaration for a subtype that
1885 -- will be used to represent the biased subtype that reflects
1886 -- the biased representation of components. We need the subtype
1887 -- to get proper conversions on referencing elements of the
1888 -- array. Note: component size clauses are ignored in VM mode.
1890 if VM_Target = No_VM then
1893 Make_Defining_Identifier (Loc,
1895 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
1898 Make_Subtype_Declaration (Loc,
1899 Defining_Identifier => New_Ctyp,
1900 Subtype_Indication =>
1901 New_Occurrence_Of (Component_Type (Btype), Loc));
1903 Set_Parent (Decl, N);
1904 Analyze (Decl, Suppress => All_Checks);
1906 Set_Has_Delayed_Freeze (New_Ctyp, False);
1907 Set_Esize (New_Ctyp, Csize);
1908 Set_RM_Size (New_Ctyp, Csize);
1909 Init_Alignment (New_Ctyp);
1910 Set_Is_Itype (New_Ctyp, True);
1911 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
1913 Set_Component_Type (Btype, New_Ctyp);
1914 Set_Biased (New_Ctyp, N, "component size clause");
1917 Set_Component_Size (Btype, Csize);
1919 -- For VM case, we ignore component size clauses
1922 -- Give a warning unless we are in GNAT mode, in which case
1923 -- the warning is suppressed since it is not useful.
1925 if not GNAT_Mode then
1927 ("?component size ignored in this configuration", N);
1931 -- Deal with warning on overridden size
1933 if Warn_On_Overridden_Size
1934 and then Has_Size_Clause (Ctyp)
1935 and then RM_Size (Ctyp) /= Csize
1938 ("?component size overrides size clause for&",
1942 Set_Has_Component_Size_Clause (Btype, True);
1943 Set_Has_Non_Standard_Rep (Btype, True);
1945 end Component_Size_Case;
1951 when Attribute_External_Tag => External_Tag :
1953 if not Is_Tagged_Type (U_Ent) then
1954 Error_Msg_N ("should be a tagged type", Nam);
1957 if Duplicate_Clause then
1961 Analyze_And_Resolve (Expr, Standard_String);
1963 if not Is_Static_Expression (Expr) then
1964 Flag_Non_Static_Expr
1965 ("static string required for tag name!", Nam);
1968 if VM_Target = No_VM then
1969 Set_Has_External_Tag_Rep_Clause (U_Ent);
1971 Error_Msg_Name_1 := Attr;
1973 ("% attribute unsupported in this configuration", Nam);
1976 if not Is_Library_Level_Entity (U_Ent) then
1978 ("?non-unique external tag supplied for &", N, U_Ent);
1980 ("?\same external tag applies to all subprogram calls", N);
1982 ("?\corresponding internal tag cannot be obtained", N);
1991 when Attribute_Input =>
1992 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
1993 Set_Has_Specified_Stream_Input (Ent);
1999 -- Machine radix attribute definition clause
2001 when Attribute_Machine_Radix => Machine_Radix : declare
2002 Radix : constant Uint := Static_Integer (Expr);
2005 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2006 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2008 elsif Duplicate_Clause then
2011 elsif Radix /= No_Uint then
2012 Set_Has_Machine_Radix_Clause (U_Ent);
2013 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2017 elsif Radix = 10 then
2018 Set_Machine_Radix_10 (U_Ent);
2020 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2029 -- Object_Size attribute definition clause
2031 when Attribute_Object_Size => Object_Size : declare
2032 Size : constant Uint := Static_Integer (Expr);
2035 pragma Warnings (Off, Biased);
2038 if not Is_Type (U_Ent) then
2039 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2041 elsif Duplicate_Clause then
2045 Check_Size (Expr, U_Ent, Size, Biased);
2053 UI_Mod (Size, 64) /= 0
2056 ("Object_Size must be 8, 16, 32, or multiple of 64",
2060 Set_Esize (U_Ent, Size);
2061 Set_Has_Object_Size_Clause (U_Ent);
2062 Alignment_Check_For_Esize_Change (U_Ent);
2070 when Attribute_Output =>
2071 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2072 Set_Has_Specified_Stream_Output (Ent);
2078 when Attribute_Read =>
2079 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2080 Set_Has_Specified_Stream_Read (Ent);
2086 -- Size attribute definition clause
2088 when Attribute_Size => Size : declare
2089 Size : constant Uint := Static_Integer (Expr);
2096 if Duplicate_Clause then
2099 elsif not Is_Type (U_Ent)
2100 and then Ekind (U_Ent) /= E_Variable
2101 and then Ekind (U_Ent) /= E_Constant
2103 Error_Msg_N ("size cannot be given for &", Nam);
2105 elsif Is_Array_Type (U_Ent)
2106 and then not Is_Constrained (U_Ent)
2109 ("size cannot be given for unconstrained array", Nam);
2111 elsif Size /= No_Uint then
2113 if VM_Target /= No_VM and then not GNAT_Mode then
2115 -- Size clause is not handled properly on VM targets.
2116 -- Display a warning unless we are in GNAT mode, in which
2117 -- case this is useless.
2120 ("?size clauses are ignored in this configuration", N);
2123 if Is_Type (U_Ent) then
2126 Etyp := Etype (U_Ent);
2129 -- Check size, note that Gigi is in charge of checking that the
2130 -- size of an array or record type is OK. Also we do not check
2131 -- the size in the ordinary fixed-point case, since it is too
2132 -- early to do so (there may be subsequent small clause that
2133 -- affects the size). We can check the size if a small clause
2134 -- has already been given.
2136 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2137 or else Has_Small_Clause (U_Ent)
2139 Check_Size (Expr, Etyp, Size, Biased);
2140 Set_Biased (U_Ent, N, "size clause", Biased);
2143 -- For types set RM_Size and Esize if possible
2145 if Is_Type (U_Ent) then
2146 Set_RM_Size (U_Ent, Size);
2148 -- For scalar types, increase Object_Size to power of 2, but
2149 -- not less than a storage unit in any case (i.e., normally
2150 -- this means it will be byte addressable).
2152 if Is_Scalar_Type (U_Ent) then
2153 if Size <= System_Storage_Unit then
2154 Init_Esize (U_Ent, System_Storage_Unit);
2155 elsif Size <= 16 then
2156 Init_Esize (U_Ent, 16);
2157 elsif Size <= 32 then
2158 Init_Esize (U_Ent, 32);
2160 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2163 -- For all other types, object size = value size. The
2164 -- backend will adjust as needed.
2167 Set_Esize (U_Ent, Size);
2170 Alignment_Check_For_Esize_Change (U_Ent);
2172 -- For objects, set Esize only
2175 if Is_Elementary_Type (Etyp) then
2176 if Size /= System_Storage_Unit
2178 Size /= System_Storage_Unit * 2
2180 Size /= System_Storage_Unit * 4
2182 Size /= System_Storage_Unit * 8
2184 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2185 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2187 ("size for primitive object must be a power of 2"
2188 & " in the range ^-^", N);
2192 Set_Esize (U_Ent, Size);
2195 Set_Has_Size_Clause (U_Ent);
2203 -- Small attribute definition clause
2205 when Attribute_Small => Small : declare
2206 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2210 Analyze_And_Resolve (Expr, Any_Real);
2212 if Etype (Expr) = Any_Type then
2215 elsif not Is_Static_Expression (Expr) then
2216 Flag_Non_Static_Expr
2217 ("small requires static expression!", Expr);
2221 Small := Expr_Value_R (Expr);
2223 if Small <= Ureal_0 then
2224 Error_Msg_N ("small value must be greater than zero", Expr);
2230 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2232 ("small requires an ordinary fixed point type", Nam);
2234 elsif Has_Small_Clause (U_Ent) then
2235 Error_Msg_N ("small already given for &", Nam);
2237 elsif Small > Delta_Value (U_Ent) then
2239 ("small value must not be greater then delta value", Nam);
2242 Set_Small_Value (U_Ent, Small);
2243 Set_Small_Value (Implicit_Base, Small);
2244 Set_Has_Small_Clause (U_Ent);
2245 Set_Has_Small_Clause (Implicit_Base);
2246 Set_Has_Non_Standard_Rep (Implicit_Base);
2254 -- Storage_Pool attribute definition clause
2256 when Attribute_Storage_Pool => Storage_Pool : declare
2261 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2263 ("storage pool cannot be given for access-to-subprogram type",
2268 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2271 ("storage pool can only be given for access types", Nam);
2274 elsif Is_Derived_Type (U_Ent) then
2276 ("storage pool cannot be given for a derived access type",
2279 elsif Duplicate_Clause then
2282 elsif Present (Associated_Storage_Pool (U_Ent)) then
2283 Error_Msg_N ("storage pool already given for &", Nam);
2288 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
2290 if not Denotes_Variable (Expr) then
2291 Error_Msg_N ("storage pool must be a variable", Expr);
2295 if Nkind (Expr) = N_Type_Conversion then
2296 T := Etype (Expression (Expr));
2301 -- The Stack_Bounded_Pool is used internally for implementing
2302 -- access types with a Storage_Size. Since it only work
2303 -- properly when used on one specific type, we need to check
2304 -- that it is not hijacked improperly:
2305 -- type T is access Integer;
2306 -- for T'Storage_Size use n;
2307 -- type Q is access Float;
2308 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
2310 if RTE_Available (RE_Stack_Bounded_Pool)
2311 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
2313 Error_Msg_N ("non-shareable internal Pool", Expr);
2317 -- If the argument is a name that is not an entity name, then
2318 -- we construct a renaming operation to define an entity of
2319 -- type storage pool.
2321 if not Is_Entity_Name (Expr)
2322 and then Is_Object_Reference (Expr)
2324 Pool := Make_Temporary (Loc, 'P', Expr);
2327 Rnode : constant Node_Id :=
2328 Make_Object_Renaming_Declaration (Loc,
2329 Defining_Identifier => Pool,
2331 New_Occurrence_Of (Etype (Expr), Loc),
2335 Insert_Before (N, Rnode);
2337 Set_Associated_Storage_Pool (U_Ent, Pool);
2340 elsif Is_Entity_Name (Expr) then
2341 Pool := Entity (Expr);
2343 -- If pool is a renamed object, get original one. This can
2344 -- happen with an explicit renaming, and within instances.
2346 while Present (Renamed_Object (Pool))
2347 and then Is_Entity_Name (Renamed_Object (Pool))
2349 Pool := Entity (Renamed_Object (Pool));
2352 if Present (Renamed_Object (Pool))
2353 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
2354 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
2356 Pool := Entity (Expression (Renamed_Object (Pool)));
2359 Set_Associated_Storage_Pool (U_Ent, Pool);
2361 elsif Nkind (Expr) = N_Type_Conversion
2362 and then Is_Entity_Name (Expression (Expr))
2363 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
2365 Pool := Entity (Expression (Expr));
2366 Set_Associated_Storage_Pool (U_Ent, Pool);
2369 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
2378 -- Storage_Size attribute definition clause
2380 when Attribute_Storage_Size => Storage_Size : declare
2381 Btype : constant Entity_Id := Base_Type (U_Ent);
2385 if Is_Task_Type (U_Ent) then
2386 Check_Restriction (No_Obsolescent_Features, N);
2388 if Warn_On_Obsolescent_Feature then
2390 ("storage size clause for task is an " &
2391 "obsolescent feature (RM J.9)?", N);
2392 Error_Msg_N ("\use Storage_Size pragma instead?", N);
2398 if not Is_Access_Type (U_Ent)
2399 and then Ekind (U_Ent) /= E_Task_Type
2401 Error_Msg_N ("storage size cannot be given for &", Nam);
2403 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
2405 ("storage size cannot be given for a derived access type",
2408 elsif Duplicate_Clause then
2412 Analyze_And_Resolve (Expr, Any_Integer);
2414 if Is_Access_Type (U_Ent) then
2415 if Present (Associated_Storage_Pool (U_Ent)) then
2416 Error_Msg_N ("storage pool already given for &", Nam);
2420 if Is_OK_Static_Expression (Expr)
2421 and then Expr_Value (Expr) = 0
2423 Set_No_Pool_Assigned (Btype);
2426 else -- Is_Task_Type (U_Ent)
2427 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
2429 if Present (Sprag) then
2430 Error_Msg_Sloc := Sloc (Sprag);
2432 ("Storage_Size already specified#", Nam);
2437 Set_Has_Storage_Size_Clause (Btype);
2445 when Attribute_Stream_Size => Stream_Size : declare
2446 Size : constant Uint := Static_Integer (Expr);
2449 if Ada_Version <= Ada_95 then
2450 Check_Restriction (No_Implementation_Attributes, N);
2453 if Duplicate_Clause then
2456 elsif Is_Elementary_Type (U_Ent) then
2457 if Size /= System_Storage_Unit
2459 Size /= System_Storage_Unit * 2
2461 Size /= System_Storage_Unit * 4
2463 Size /= System_Storage_Unit * 8
2465 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2467 ("stream size for elementary type must be a"
2468 & " power of 2 and at least ^", N);
2470 elsif RM_Size (U_Ent) > Size then
2471 Error_Msg_Uint_1 := RM_Size (U_Ent);
2473 ("stream size for elementary type must be a"
2474 & " power of 2 and at least ^", N);
2477 Set_Has_Stream_Size_Clause (U_Ent);
2480 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
2488 -- Value_Size attribute definition clause
2490 when Attribute_Value_Size => Value_Size : declare
2491 Size : constant Uint := Static_Integer (Expr);
2495 if not Is_Type (U_Ent) then
2496 Error_Msg_N ("Value_Size cannot be given for &", Nam);
2498 elsif Duplicate_Clause then
2501 elsif Is_Array_Type (U_Ent)
2502 and then not Is_Constrained (U_Ent)
2505 ("Value_Size cannot be given for unconstrained array", Nam);
2508 if Is_Elementary_Type (U_Ent) then
2509 Check_Size (Expr, U_Ent, Size, Biased);
2510 Set_Biased (U_Ent, N, "value size clause", Biased);
2513 Set_RM_Size (U_Ent, Size);
2521 when Attribute_Write =>
2522 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
2523 Set_Has_Specified_Stream_Write (Ent);
2525 -- All other attributes cannot be set
2529 ("attribute& cannot be set with definition clause", N);
2532 -- The test for the type being frozen must be performed after
2533 -- any expression the clause has been analyzed since the expression
2534 -- itself might cause freezing that makes the clause illegal.
2536 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
2539 end Analyze_Attribute_Definition_Clause;
2541 ----------------------------
2542 -- Analyze_Code_Statement --
2543 ----------------------------
2545 procedure Analyze_Code_Statement (N : Node_Id) is
2546 HSS : constant Node_Id := Parent (N);
2547 SBody : constant Node_Id := Parent (HSS);
2548 Subp : constant Entity_Id := Current_Scope;
2555 -- Analyze and check we get right type, note that this implements the
2556 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
2557 -- is the only way that Asm_Insn could possibly be visible.
2559 Analyze_And_Resolve (Expression (N));
2561 if Etype (Expression (N)) = Any_Type then
2563 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
2564 Error_Msg_N ("incorrect type for code statement", N);
2568 Check_Code_Statement (N);
2570 -- Make sure we appear in the handled statement sequence of a
2571 -- subprogram (RM 13.8(3)).
2573 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
2574 or else Nkind (SBody) /= N_Subprogram_Body
2577 ("code statement can only appear in body of subprogram", N);
2581 -- Do remaining checks (RM 13.8(3)) if not already done
2583 if not Is_Machine_Code_Subprogram (Subp) then
2584 Set_Is_Machine_Code_Subprogram (Subp);
2586 -- No exception handlers allowed
2588 if Present (Exception_Handlers (HSS)) then
2590 ("exception handlers not permitted in machine code subprogram",
2591 First (Exception_Handlers (HSS)));
2594 -- No declarations other than use clauses and pragmas (we allow
2595 -- certain internally generated declarations as well).
2597 Decl := First (Declarations (SBody));
2598 while Present (Decl) loop
2599 DeclO := Original_Node (Decl);
2600 if Comes_From_Source (DeclO)
2601 and not Nkind_In (DeclO, N_Pragma,
2602 N_Use_Package_Clause,
2604 N_Implicit_Label_Declaration)
2607 ("this declaration not allowed in machine code subprogram",
2614 -- No statements other than code statements, pragmas, and labels.
2615 -- Again we allow certain internally generated statements.
2617 Stmt := First (Statements (HSS));
2618 while Present (Stmt) loop
2619 StmtO := Original_Node (Stmt);
2620 if Comes_From_Source (StmtO)
2621 and then not Nkind_In (StmtO, N_Pragma,
2626 ("this statement is not allowed in machine code subprogram",
2633 end Analyze_Code_Statement;
2635 -----------------------------------------------
2636 -- Analyze_Enumeration_Representation_Clause --
2637 -----------------------------------------------
2639 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
2640 Ident : constant Node_Id := Identifier (N);
2641 Aggr : constant Node_Id := Array_Aggregate (N);
2642 Enumtype : Entity_Id;
2648 Err : Boolean := False;
2650 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
2651 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
2652 -- Allowed range of universal integer (= allowed range of enum lit vals)
2656 -- Minimum and maximum values of entries
2659 -- Pointer to node for literal providing max value
2662 if Ignore_Rep_Clauses then
2666 -- First some basic error checks
2669 Enumtype := Entity (Ident);
2671 if Enumtype = Any_Type
2672 or else Rep_Item_Too_Early (Enumtype, N)
2676 Enumtype := Underlying_Type (Enumtype);
2679 if not Is_Enumeration_Type (Enumtype) then
2681 ("enumeration type required, found}",
2682 Ident, First_Subtype (Enumtype));
2686 -- Ignore rep clause on generic actual type. This will already have
2687 -- been flagged on the template as an error, and this is the safest
2688 -- way to ensure we don't get a junk cascaded message in the instance.
2690 if Is_Generic_Actual_Type (Enumtype) then
2693 -- Type must be in current scope
2695 elsif Scope (Enumtype) /= Current_Scope then
2696 Error_Msg_N ("type must be declared in this scope", Ident);
2699 -- Type must be a first subtype
2701 elsif not Is_First_Subtype (Enumtype) then
2702 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
2705 -- Ignore duplicate rep clause
2707 elsif Has_Enumeration_Rep_Clause (Enumtype) then
2708 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
2711 -- Don't allow rep clause for standard [wide_[wide_]]character
2713 elsif Is_Standard_Character_Type (Enumtype) then
2714 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
2717 -- Check that the expression is a proper aggregate (no parentheses)
2719 elsif Paren_Count (Aggr) /= 0 then
2721 ("extra parentheses surrounding aggregate not allowed",
2725 -- All tests passed, so set rep clause in place
2728 Set_Has_Enumeration_Rep_Clause (Enumtype);
2729 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
2732 -- Now we process the aggregate. Note that we don't use the normal
2733 -- aggregate code for this purpose, because we don't want any of the
2734 -- normal expansion activities, and a number of special semantic
2735 -- rules apply (including the component type being any integer type)
2737 Elit := First_Literal (Enumtype);
2739 -- First the positional entries if any
2741 if Present (Expressions (Aggr)) then
2742 Expr := First (Expressions (Aggr));
2743 while Present (Expr) loop
2745 Error_Msg_N ("too many entries in aggregate", Expr);
2749 Val := Static_Integer (Expr);
2751 -- Err signals that we found some incorrect entries processing
2752 -- the list. The final checks for completeness and ordering are
2753 -- skipped in this case.
2755 if Val = No_Uint then
2757 elsif Val < Lo or else Hi < Val then
2758 Error_Msg_N ("value outside permitted range", Expr);
2762 Set_Enumeration_Rep (Elit, Val);
2763 Set_Enumeration_Rep_Expr (Elit, Expr);
2769 -- Now process the named entries if present
2771 if Present (Component_Associations (Aggr)) then
2772 Assoc := First (Component_Associations (Aggr));
2773 while Present (Assoc) loop
2774 Choice := First (Choices (Assoc));
2776 if Present (Next (Choice)) then
2778 ("multiple choice not allowed here", Next (Choice));
2782 if Nkind (Choice) = N_Others_Choice then
2783 Error_Msg_N ("others choice not allowed here", Choice);
2786 elsif Nkind (Choice) = N_Range then
2787 -- ??? should allow zero/one element range here
2788 Error_Msg_N ("range not allowed here", Choice);
2792 Analyze_And_Resolve (Choice, Enumtype);
2794 if Is_Entity_Name (Choice)
2795 and then Is_Type (Entity (Choice))
2797 Error_Msg_N ("subtype name not allowed here", Choice);
2799 -- ??? should allow static subtype with zero/one entry
2801 elsif Etype (Choice) = Base_Type (Enumtype) then
2802 if not Is_Static_Expression (Choice) then
2803 Flag_Non_Static_Expr
2804 ("non-static expression used for choice!", Choice);
2808 Elit := Expr_Value_E (Choice);
2810 if Present (Enumeration_Rep_Expr (Elit)) then
2811 Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit));
2813 ("representation for& previously given#",
2818 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
2820 Expr := Expression (Assoc);
2821 Val := Static_Integer (Expr);
2823 if Val = No_Uint then
2826 elsif Val < Lo or else Hi < Val then
2827 Error_Msg_N ("value outside permitted range", Expr);
2831 Set_Enumeration_Rep (Elit, Val);
2840 -- Aggregate is fully processed. Now we check that a full set of
2841 -- representations was given, and that they are in range and in order.
2842 -- These checks are only done if no other errors occurred.
2848 Elit := First_Literal (Enumtype);
2849 while Present (Elit) loop
2850 if No (Enumeration_Rep_Expr (Elit)) then
2851 Error_Msg_NE ("missing representation for&!", N, Elit);
2854 Val := Enumeration_Rep (Elit);
2856 if Min = No_Uint then
2860 if Val /= No_Uint then
2861 if Max /= No_Uint and then Val <= Max then
2863 ("enumeration value for& not ordered!",
2864 Enumeration_Rep_Expr (Elit), Elit);
2867 Max_Node := Enumeration_Rep_Expr (Elit);
2871 -- If there is at least one literal whose representation is not
2872 -- equal to the Pos value, then note that this enumeration type
2873 -- has a non-standard representation.
2875 if Val /= Enumeration_Pos (Elit) then
2876 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
2883 -- Now set proper size information
2886 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
2889 if Has_Size_Clause (Enumtype) then
2891 -- All OK, if size is OK now
2893 if RM_Size (Enumtype) >= Minsize then
2897 -- Try if we can get by with biasing
2900 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
2902 -- Error message if even biasing does not work
2904 if RM_Size (Enumtype) < Minsize then
2905 Error_Msg_Uint_1 := RM_Size (Enumtype);
2906 Error_Msg_Uint_2 := Max;
2908 ("previously given size (^) is too small "
2909 & "for this value (^)", Max_Node);
2911 -- If biasing worked, indicate that we now have biased rep
2915 (Enumtype, Size_Clause (Enumtype), "size clause");
2920 Set_RM_Size (Enumtype, Minsize);
2921 Set_Enum_Esize (Enumtype);
2924 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
2925 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
2926 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
2930 -- We repeat the too late test in case it froze itself!
2932 if Rep_Item_Too_Late (Enumtype, N) then
2935 end Analyze_Enumeration_Representation_Clause;
2937 ----------------------------
2938 -- Analyze_Free_Statement --
2939 ----------------------------
2941 procedure Analyze_Free_Statement (N : Node_Id) is
2943 Analyze (Expression (N));
2944 end Analyze_Free_Statement;
2946 ---------------------------
2947 -- Analyze_Freeze_Entity --
2948 ---------------------------
2950 procedure Analyze_Freeze_Entity (N : Node_Id) is
2951 E : constant Entity_Id := Entity (N);
2954 -- Remember that we are processing a freezing entity. Required to
2955 -- ensure correct decoration of internal entities associated with
2956 -- interfaces (see New_Overloaded_Entity).
2958 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
2960 -- For tagged types covering interfaces add internal entities that link
2961 -- the primitives of the interfaces with the primitives that cover them.
2962 -- Note: These entities were originally generated only when generating
2963 -- code because their main purpose was to provide support to initialize
2964 -- the secondary dispatch tables. They are now generated also when
2965 -- compiling with no code generation to provide ASIS the relationship
2966 -- between interface primitives and tagged type primitives. They are
2967 -- also used to locate primitives covering interfaces when processing
2968 -- generics (see Derive_Subprograms).
2970 if Ada_Version >= Ada_2005
2971 and then Ekind (E) = E_Record_Type
2972 and then Is_Tagged_Type (E)
2973 and then not Is_Interface (E)
2974 and then Has_Interfaces (E)
2976 -- This would be a good common place to call the routine that checks
2977 -- overriding of interface primitives (and thus factorize calls to
2978 -- Check_Abstract_Overriding located at different contexts in the
2979 -- compiler). However, this is not possible because it causes
2980 -- spurious errors in case of late overriding.
2982 Add_Internal_Interface_Entities (E);
2987 if Ekind (E) = E_Record_Type
2988 and then Is_CPP_Class (E)
2989 and then Is_Tagged_Type (E)
2990 and then Tagged_Type_Expansion
2991 and then Expander_Active
2993 if CPP_Num_Prims (E) = 0 then
2995 -- If the CPP type has user defined components then it must import
2996 -- primitives from C++. This is required because if the C++ class
2997 -- has no primitives then the C++ compiler does not added the _tag
2998 -- component to the type.
3000 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3002 if First_Entity (E) /= Last_Entity (E) then
3004 ("?'C'P'P type must import at least one primitive from C++",
3009 -- Check that all its primitives are abstract or imported from C++.
3010 -- Check also availability of the C++ constructor.
3013 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3015 Error_Reported : Boolean := False;
3019 Elmt := First_Elmt (Primitive_Operations (E));
3020 while Present (Elmt) loop
3021 Prim := Node (Elmt);
3023 if Comes_From_Source (Prim) then
3024 if Is_Abstract_Subprogram (Prim) then
3027 elsif not Is_Imported (Prim)
3028 or else Convention (Prim) /= Convention_CPP
3031 ("?primitives of 'C'P'P types must be imported from C++"
3032 & " or abstract", Prim);
3034 elsif not Has_Constructors
3035 and then not Error_Reported
3037 Error_Msg_Name_1 := Chars (E);
3039 ("?'C'P'P constructor required for type %", Prim);
3040 Error_Reported := True;
3049 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3051 -- If we have a type with predicates, build predicate function
3053 if Is_Type (E) and then Has_Predicates (E) then
3054 Build_Predicate_Function (E, N);
3057 -- If type has delayed aspects, this is where we do the preanalysis
3058 -- at the freeze point, as part of the consistent visibility check.
3059 -- Note that this must be done after calling Build_Predicate_Function,
3060 -- since that call marks occurrences of the subtype name in the saved
3061 -- expression so that they will not cause trouble in the preanalysis.
3063 if Has_Delayed_Aspects (E) then
3068 -- Look for aspect specification entries for this entity
3070 Ritem := First_Rep_Item (E);
3071 while Present (Ritem) loop
3072 if Nkind (Ritem) = N_Aspect_Specification
3073 and then Entity (Ritem) = E
3074 and then Is_Delayed_Aspect (Ritem)
3076 Check_Aspect_At_Freeze_Point (Ritem);
3079 Next_Rep_Item (Ritem);
3083 end Analyze_Freeze_Entity;
3085 ------------------------------------------
3086 -- Analyze_Record_Representation_Clause --
3087 ------------------------------------------
3089 -- Note: we check as much as we can here, but we can't do any checks
3090 -- based on the position values (e.g. overlap checks) until freeze time
3091 -- because especially in Ada 2005 (machine scalar mode), the processing
3092 -- for non-standard bit order can substantially change the positions.
3093 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3094 -- for the remainder of this processing.
3096 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3097 Ident : constant Node_Id := Identifier (N);
3102 Hbit : Uint := Uint_0;
3106 Rectype : Entity_Id;
3108 CR_Pragma : Node_Id := Empty;
3109 -- Points to N_Pragma node if Complete_Representation pragma present
3112 if Ignore_Rep_Clauses then
3117 Rectype := Entity (Ident);
3119 if Rectype = Any_Type
3120 or else Rep_Item_Too_Early (Rectype, N)
3124 Rectype := Underlying_Type (Rectype);
3127 -- First some basic error checks
3129 if not Is_Record_Type (Rectype) then
3131 ("record type required, found}", Ident, First_Subtype (Rectype));
3134 elsif Scope (Rectype) /= Current_Scope then
3135 Error_Msg_N ("type must be declared in this scope", N);
3138 elsif not Is_First_Subtype (Rectype) then
3139 Error_Msg_N ("cannot give record rep clause for subtype", N);
3142 elsif Has_Record_Rep_Clause (Rectype) then
3143 Error_Msg_N ("duplicate record rep clause ignored", N);
3146 elsif Rep_Item_Too_Late (Rectype, N) then
3150 if Present (Mod_Clause (N)) then
3152 Loc : constant Source_Ptr := Sloc (N);
3153 M : constant Node_Id := Mod_Clause (N);
3154 P : constant List_Id := Pragmas_Before (M);
3158 pragma Warnings (Off, Mod_Val);
3161 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3163 if Warn_On_Obsolescent_Feature then
3165 ("mod clause is an obsolescent feature (RM J.8)?", N);
3167 ("\use alignment attribute definition clause instead?", N);
3174 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3175 -- the Mod clause into an alignment clause anyway, so that the
3176 -- back-end can compute and back-annotate properly the size and
3177 -- alignment of types that may include this record.
3179 -- This seems dubious, this destroys the source tree in a manner
3180 -- not detectable by ASIS ???
3182 if Operating_Mode = Check_Semantics
3186 Make_Attribute_Definition_Clause (Loc,
3187 Name => New_Reference_To (Base_Type (Rectype), Loc),
3188 Chars => Name_Alignment,
3189 Expression => Relocate_Node (Expression (M)));
3191 Set_From_At_Mod (AtM_Nod);
3192 Insert_After (N, AtM_Nod);
3193 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3194 Set_Mod_Clause (N, Empty);
3197 -- Get the alignment value to perform error checking
3199 Mod_Val := Get_Alignment_Value (Expression (M));
3204 -- For untagged types, clear any existing component clauses for the
3205 -- type. If the type is derived, this is what allows us to override
3206 -- a rep clause for the parent. For type extensions, the representation
3207 -- of the inherited components is inherited, so we want to keep previous
3208 -- component clauses for completeness.
3210 if not Is_Tagged_Type (Rectype) then
3211 Comp := First_Component_Or_Discriminant (Rectype);
3212 while Present (Comp) loop
3213 Set_Component_Clause (Comp, Empty);
3214 Next_Component_Or_Discriminant (Comp);
3218 -- All done if no component clauses
3220 CC := First (Component_Clauses (N));
3226 -- A representation like this applies to the base type
3228 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3229 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3230 Set_Has_Specified_Layout (Base_Type (Rectype));
3232 -- Process the component clauses
3234 while Present (CC) loop
3238 if Nkind (CC) = N_Pragma then
3241 -- The only pragma of interest is Complete_Representation
3243 if Pragma_Name (CC) = Name_Complete_Representation then
3247 -- Processing for real component clause
3250 Posit := Static_Integer (Position (CC));
3251 Fbit := Static_Integer (First_Bit (CC));
3252 Lbit := Static_Integer (Last_Bit (CC));
3255 and then Fbit /= No_Uint
3256 and then Lbit /= No_Uint
3260 ("position cannot be negative", Position (CC));
3264 ("first bit cannot be negative", First_Bit (CC));
3266 -- The Last_Bit specified in a component clause must not be
3267 -- less than the First_Bit minus one (RM-13.5.1(10)).
3269 elsif Lbit < Fbit - 1 then
3271 ("last bit cannot be less than first bit minus one",
3274 -- Values look OK, so find the corresponding record component
3275 -- Even though the syntax allows an attribute reference for
3276 -- implementation-defined components, GNAT does not allow the
3277 -- tag to get an explicit position.
3279 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
3280 if Attribute_Name (Component_Name (CC)) = Name_Tag then
3281 Error_Msg_N ("position of tag cannot be specified", CC);
3283 Error_Msg_N ("illegal component name", CC);
3287 Comp := First_Entity (Rectype);
3288 while Present (Comp) loop
3289 exit when Chars (Comp) = Chars (Component_Name (CC));
3295 -- Maybe component of base type that is absent from
3296 -- statically constrained first subtype.
3298 Comp := First_Entity (Base_Type (Rectype));
3299 while Present (Comp) loop
3300 exit when Chars (Comp) = Chars (Component_Name (CC));
3307 ("component clause is for non-existent field", CC);
3309 -- Ada 2012 (AI05-0026): Any name that denotes a
3310 -- discriminant of an object of an unchecked union type
3311 -- shall not occur within a record_representation_clause.
3313 -- The general restriction of using record rep clauses on
3314 -- Unchecked_Union types has now been lifted. Since it is
3315 -- possible to introduce a record rep clause which mentions
3316 -- the discriminant of an Unchecked_Union in non-Ada 2012
3317 -- code, this check is applied to all versions of the
3320 elsif Ekind (Comp) = E_Discriminant
3321 and then Is_Unchecked_Union (Rectype)
3324 ("cannot reference discriminant of Unchecked_Union",
3325 Component_Name (CC));
3327 elsif Present (Component_Clause (Comp)) then
3329 -- Diagnose duplicate rep clause, or check consistency
3330 -- if this is an inherited component. In a double fault,
3331 -- there may be a duplicate inconsistent clause for an
3332 -- inherited component.
3334 if Scope (Original_Record_Component (Comp)) = Rectype
3335 or else Parent (Component_Clause (Comp)) = N
3337 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
3338 Error_Msg_N ("component clause previously given#", CC);
3342 Rep1 : constant Node_Id := Component_Clause (Comp);
3344 if Intval (Position (Rep1)) /=
3345 Intval (Position (CC))
3346 or else Intval (First_Bit (Rep1)) /=
3347 Intval (First_Bit (CC))
3348 or else Intval (Last_Bit (Rep1)) /=
3349 Intval (Last_Bit (CC))
3351 Error_Msg_N ("component clause inconsistent "
3352 & "with representation of ancestor", CC);
3353 elsif Warn_On_Redundant_Constructs then
3354 Error_Msg_N ("?redundant component clause "
3355 & "for inherited component!", CC);
3360 -- Normal case where this is the first component clause we
3361 -- have seen for this entity, so set it up properly.
3364 -- Make reference for field in record rep clause and set
3365 -- appropriate entity field in the field identifier.
3368 (Comp, Component_Name (CC), Set_Ref => False);
3369 Set_Entity (Component_Name (CC), Comp);
3371 -- Update Fbit and Lbit to the actual bit number
3373 Fbit := Fbit + UI_From_Int (SSU) * Posit;
3374 Lbit := Lbit + UI_From_Int (SSU) * Posit;
3376 if Has_Size_Clause (Rectype)
3377 and then Esize (Rectype) <= Lbit
3380 ("bit number out of range of specified size",
3383 Set_Component_Clause (Comp, CC);
3384 Set_Component_Bit_Offset (Comp, Fbit);
3385 Set_Esize (Comp, 1 + (Lbit - Fbit));
3386 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
3387 Set_Normalized_Position (Comp, Fbit / SSU);
3389 if Warn_On_Overridden_Size
3390 and then Has_Size_Clause (Etype (Comp))
3391 and then RM_Size (Etype (Comp)) /= Esize (Comp)
3394 ("?component size overrides size clause for&",
3395 Component_Name (CC), Etype (Comp));
3398 -- This information is also set in the corresponding
3399 -- component of the base type, found by accessing the
3400 -- Original_Record_Component link if it is present.
3402 Ocomp := Original_Record_Component (Comp);
3409 (Component_Name (CC),
3415 (Comp, First_Node (CC), "component clause", Biased);
3417 if Present (Ocomp) then
3418 Set_Component_Clause (Ocomp, CC);
3419 Set_Component_Bit_Offset (Ocomp, Fbit);
3420 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
3421 Set_Normalized_Position (Ocomp, Fbit / SSU);
3422 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
3424 Set_Normalized_Position_Max
3425 (Ocomp, Normalized_Position (Ocomp));
3427 -- Note: we don't use Set_Biased here, because we
3428 -- already gave a warning above if needed, and we
3429 -- would get a duplicate for the same name here.
3431 Set_Has_Biased_Representation
3432 (Ocomp, Has_Biased_Representation (Comp));
3435 if Esize (Comp) < 0 then
3436 Error_Msg_N ("component size is negative", CC);
3447 -- Check missing components if Complete_Representation pragma appeared
3449 if Present (CR_Pragma) then
3450 Comp := First_Component_Or_Discriminant (Rectype);
3451 while Present (Comp) loop
3452 if No (Component_Clause (Comp)) then
3454 ("missing component clause for &", CR_Pragma, Comp);
3457 Next_Component_Or_Discriminant (Comp);
3460 -- If no Complete_Representation pragma, warn if missing components
3462 elsif Warn_On_Unrepped_Components then
3464 Num_Repped_Components : Nat := 0;
3465 Num_Unrepped_Components : Nat := 0;
3468 -- First count number of repped and unrepped components
3470 Comp := First_Component_Or_Discriminant (Rectype);
3471 while Present (Comp) loop
3472 if Present (Component_Clause (Comp)) then
3473 Num_Repped_Components := Num_Repped_Components + 1;
3475 Num_Unrepped_Components := Num_Unrepped_Components + 1;
3478 Next_Component_Or_Discriminant (Comp);
3481 -- We are only interested in the case where there is at least one
3482 -- unrepped component, and at least half the components have rep
3483 -- clauses. We figure that if less than half have them, then the
3484 -- partial rep clause is really intentional. If the component
3485 -- type has no underlying type set at this point (as for a generic
3486 -- formal type), we don't know enough to give a warning on the
3489 if Num_Unrepped_Components > 0
3490 and then Num_Unrepped_Components < Num_Repped_Components
3492 Comp := First_Component_Or_Discriminant (Rectype);
3493 while Present (Comp) loop
3494 if No (Component_Clause (Comp))
3495 and then Comes_From_Source (Comp)
3496 and then Present (Underlying_Type (Etype (Comp)))
3497 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
3498 or else Size_Known_At_Compile_Time
3499 (Underlying_Type (Etype (Comp))))
3500 and then not Has_Warnings_Off (Rectype)
3502 Error_Msg_Sloc := Sloc (Comp);
3504 ("?no component clause given for & declared #",
3508 Next_Component_Or_Discriminant (Comp);
3513 end Analyze_Record_Representation_Clause;
3515 -------------------------------
3516 -- Build_Invariant_Procedure --
3517 -------------------------------
3519 -- The procedure that is constructed here has the form
3521 -- procedure typInvariant (Ixxx : typ) is
3523 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3524 -- pragma Check (Invariant, exp, "failed invariant from xxx");
3526 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
3528 -- end typInvariant;
3530 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
3531 Loc : constant Source_Ptr := Sloc (Typ);
3538 Visible_Decls : constant List_Id := Visible_Declarations (N);
3539 Private_Decls : constant List_Id := Private_Declarations (N);
3541 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
3542 -- Appends statements to Stmts for any invariants in the rep item chain
3543 -- of the given type. If Inherit is False, then we only process entries
3544 -- on the chain for the type Typ. If Inherit is True, then we ignore any
3545 -- Invariant aspects, but we process all Invariant'Class aspects, adding
3546 -- "inherited" to the exception message and generating an informational
3547 -- message about the inheritance of an invariant.
3549 Object_Name : constant Name_Id := New_Internal_Name ('I');
3550 -- Name for argument of invariant procedure
3552 Object_Entity : constant Node_Id :=
3553 Make_Defining_Identifier (Loc, Object_Name);
3554 -- The procedure declaration entity for the argument
3556 --------------------
3557 -- Add_Invariants --
3558 --------------------
3560 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
3570 procedure Replace_Type_Reference (N : Node_Id);
3571 -- Replace a single occurrence N of the subtype name with a reference
3572 -- to the formal of the predicate function. N can be an identifier
3573 -- referencing the subtype, or a selected component, representing an
3574 -- appropriately qualified occurrence of the subtype name.
3576 procedure Replace_Type_References is
3577 new Replace_Type_References_Generic (Replace_Type_Reference);
3578 -- Traverse an expression replacing all occurrences of the subtype
3579 -- name with appropriate references to the object that is the formal
3580 -- parameter of the predicate function. Note that we must ensure
3581 -- that the type and entity information is properly set in the
3582 -- replacement node, since we will do a Preanalyze call of this
3583 -- expression without proper visibility of the procedure argument.
3585 ----------------------------
3586 -- Replace_Type_Reference --
3587 ----------------------------
3589 procedure Replace_Type_Reference (N : Node_Id) is
3591 -- Invariant'Class, replace with T'Class (obj)
3593 if Class_Present (Ritem) then
3595 Make_Type_Conversion (Loc,
3597 Make_Attribute_Reference (Loc,
3598 Prefix => New_Occurrence_Of (T, Loc),
3599 Attribute_Name => Name_Class),
3600 Expression => Make_Identifier (Loc, Object_Name)));
3602 Set_Entity (Expression (N), Object_Entity);
3603 Set_Etype (Expression (N), Typ);
3605 -- Invariant, replace with obj
3608 Rewrite (N, Make_Identifier (Loc, Object_Name));
3609 Set_Entity (N, Object_Entity);
3612 end Replace_Type_Reference;
3614 -- Start of processing for Add_Invariants
3617 Ritem := First_Rep_Item (T);
3618 while Present (Ritem) loop
3619 if Nkind (Ritem) = N_Pragma
3620 and then Pragma_Name (Ritem) = Name_Invariant
3622 Arg1 := First (Pragma_Argument_Associations (Ritem));
3623 Arg2 := Next (Arg1);
3624 Arg3 := Next (Arg2);
3626 Arg1 := Get_Pragma_Arg (Arg1);
3627 Arg2 := Get_Pragma_Arg (Arg2);
3629 -- For Inherit case, ignore Invariant, process only Class case
3632 if not Class_Present (Ritem) then
3636 -- For Inherit false, process only item for right type
3639 if Entity (Arg1) /= Typ then
3645 Stmts := Empty_List;
3648 Exp := New_Copy_Tree (Arg2);
3651 -- We need to replace any occurrences of the name of the type
3652 -- with references to the object, converted to type'Class in
3653 -- the case of Invariant'Class aspects.
3655 Replace_Type_References (Exp, Chars (T));
3657 -- If this invariant comes from an aspect, find the aspect
3658 -- specification, and replace the saved expression because
3659 -- we need the subtype references replaced for the calls to
3660 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
3661 -- and Check_Aspect_At_End_Of_Declarations.
3663 if From_Aspect_Specification (Ritem) then
3668 -- Loop to find corresponding aspect, note that this
3669 -- must be present given the pragma is marked delayed.
3671 Aitem := Next_Rep_Item (Ritem);
3672 while Present (Aitem) loop
3673 if Nkind (Aitem) = N_Aspect_Specification
3674 and then Aspect_Rep_Item (Aitem) = Ritem
3677 (Identifier (Aitem), New_Copy_Tree (Exp));
3681 Aitem := Next_Rep_Item (Aitem);
3686 -- Now we need to preanalyze the expression to properly capture
3687 -- the visibility in the visible part. The expression will not
3688 -- be analyzed for real until the body is analyzed, but that is
3689 -- at the end of the private part and has the wrong visibility.
3691 Set_Parent (Exp, N);
3692 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
3694 -- Build first two arguments for Check pragma
3697 Make_Pragma_Argument_Association (Loc,
3698 Expression => Make_Identifier (Loc, Name_Invariant)),
3699 Make_Pragma_Argument_Association (Loc, Expression => Exp));
3701 -- Add message if present in Invariant pragma
3703 if Present (Arg3) then
3704 Str := Strval (Get_Pragma_Arg (Arg3));
3706 -- If inherited case, and message starts "failed invariant",
3707 -- change it to be "failed inherited invariant".
3710 String_To_Name_Buffer (Str);
3712 if Name_Buffer (1 .. 16) = "failed invariant" then
3713 Insert_Str_In_Name_Buffer ("inherited ", 8);
3714 Str := String_From_Name_Buffer;
3719 Make_Pragma_Argument_Association (Loc,
3720 Expression => Make_String_Literal (Loc, Str)));
3723 -- Add Check pragma to list of statements
3727 Pragma_Identifier =>
3728 Make_Identifier (Loc, Name_Check),
3729 Pragma_Argument_Associations => Assoc));
3731 -- If Inherited case and option enabled, output info msg. Note
3732 -- that we know this is a case of Invariant'Class.
3734 if Inherit and Opt.List_Inherited_Aspects then
3735 Error_Msg_Sloc := Sloc (Ritem);
3737 ("?info: & inherits `Invariant''Class` aspect from #",
3743 Next_Rep_Item (Ritem);
3747 -- Start of processing for Build_Invariant_Procedure
3753 Set_Etype (Object_Entity, Typ);
3755 -- Add invariants for the current type
3757 Add_Invariants (Typ, Inherit => False);
3759 -- Add invariants for parent types
3762 Current_Typ : Entity_Id;
3763 Parent_Typ : Entity_Id;
3768 Parent_Typ := Etype (Current_Typ);
3770 if Is_Private_Type (Parent_Typ)
3771 and then Present (Full_View (Base_Type (Parent_Typ)))
3773 Parent_Typ := Full_View (Base_Type (Parent_Typ));
3776 exit when Parent_Typ = Current_Typ;
3778 Current_Typ := Parent_Typ;
3779 Add_Invariants (Current_Typ, Inherit => True);
3783 -- Build the procedure if we generated at least one Check pragma
3785 if Stmts /= No_List then
3787 -- Build procedure declaration
3790 Make_Defining_Identifier (Loc,
3791 Chars => New_External_Name (Chars (Typ), "Invariant"));
3792 Set_Has_Invariants (SId);
3793 Set_Invariant_Procedure (Typ, SId);
3796 Make_Procedure_Specification (Loc,
3797 Defining_Unit_Name => SId,
3798 Parameter_Specifications => New_List (
3799 Make_Parameter_Specification (Loc,
3800 Defining_Identifier => Object_Entity,
3801 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3803 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
3805 -- Build procedure body
3808 Make_Defining_Identifier (Loc,
3809 Chars => New_External_Name (Chars (Typ), "Invariant"));
3812 Make_Procedure_Specification (Loc,
3813 Defining_Unit_Name => SId,
3814 Parameter_Specifications => New_List (
3815 Make_Parameter_Specification (Loc,
3816 Defining_Identifier =>
3817 Make_Defining_Identifier (Loc, Object_Name),
3818 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
3821 Make_Subprogram_Body (Loc,
3822 Specification => Spec,
3823 Declarations => Empty_List,
3824 Handled_Statement_Sequence =>
3825 Make_Handled_Sequence_Of_Statements (Loc,
3826 Statements => Stmts));
3828 -- Insert procedure declaration and spec at the appropriate points.
3829 -- Skip this if there are no private declarations (that's an error
3830 -- that will be diagnosed elsewhere, and there is no point in having
3831 -- an invariant procedure set if the full declaration is missing).
3833 if Present (Private_Decls) then
3835 -- The spec goes at the end of visible declarations, but they have
3836 -- already been analyzed, so we need to explicitly do the analyze.
3838 Append_To (Visible_Decls, PDecl);
3841 -- The body goes at the end of the private declarations, which we
3842 -- have not analyzed yet, so we do not need to perform an explicit
3843 -- analyze call. We skip this if there are no private declarations
3844 -- (this is an error that will be caught elsewhere);
3846 Append_To (Private_Decls, PBody);
3849 end Build_Invariant_Procedure;
3851 ------------------------------
3852 -- Build_Predicate_Function --
3853 ------------------------------
3855 -- The procedure that is constructed here has the form
3857 -- function typPredicate (Ixxx : typ) return Boolean is
3860 -- exp1 and then exp2 and then ...
3861 -- and then typ1Predicate (typ1 (Ixxx))
3862 -- and then typ2Predicate (typ2 (Ixxx))
3864 -- end typPredicate;
3866 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
3867 -- this is the point at which these expressions get analyzed, providing the
3868 -- required delay, and typ1, typ2, are entities from which predicates are
3869 -- inherited. Note that we do NOT generate Check pragmas, that's because we
3870 -- use this function even if checks are off, e.g. for membership tests.
3872 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
3873 Loc : constant Source_Ptr := Sloc (Typ);
3880 -- This is the expression for the return statement in the function. It
3881 -- is build by connecting the component predicates with AND THEN.
3883 procedure Add_Call (T : Entity_Id);
3884 -- Includes a call to the predicate function for type T in Expr if T
3885 -- has predicates and Predicate_Function (T) is non-empty.
3887 procedure Add_Predicates;
3888 -- Appends expressions for any Predicate pragmas in the rep item chain
3889 -- Typ to Expr. Note that we look only at items for this exact entity.
3890 -- Inheritance of predicates for the parent type is done by calling the
3891 -- Predicate_Function of the parent type, using Add_Call above.
3893 Object_Name : constant Name_Id := New_Internal_Name ('I');
3894 -- Name for argument of Predicate procedure
3896 Object_Entity : constant Entity_Id :=
3897 Make_Defining_Identifier (Loc, Object_Name);
3898 -- The entity for the spec entity for the argument
3900 Dynamic_Predicate_Present : Boolean := False;
3901 -- Set True if a dynamic predicate is present, results in the entire
3902 -- predicate being considered dynamic even if it looks static
3904 Static_Predicate_Present : Node_Id := Empty;
3905 -- Set to N_Pragma node for a static predicate if one is encountered.
3911 procedure Add_Call (T : Entity_Id) is
3915 if Present (T) and then Present (Predicate_Function (T)) then
3916 Set_Has_Predicates (Typ);
3918 -- Build the call to the predicate function of T
3922 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
3924 -- Add call to evolving expression, using AND THEN if needed
3931 Left_Opnd => Relocate_Node (Expr),
3935 -- Output info message on inheritance if required. Note we do not
3936 -- give this information for generic actual types, since it is
3937 -- unwelcome noise in that case in instantiations. We also
3938 -- generally suppress the message in instantiations, and also
3939 -- if it involves internal names.
3941 if Opt.List_Inherited_Aspects
3942 and then not Is_Generic_Actual_Type (Typ)
3943 and then Instantiation_Depth (Sloc (Typ)) = 0
3944 and then not Is_Internal_Name (Chars (T))
3945 and then not Is_Internal_Name (Chars (Typ))
3947 Error_Msg_Sloc := Sloc (Predicate_Function (T));
3948 Error_Msg_Node_2 := T;
3949 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
3954 --------------------
3955 -- Add_Predicates --
3956 --------------------
3958 procedure Add_Predicates is
3963 procedure Replace_Type_Reference (N : Node_Id);
3964 -- Replace a single occurrence N of the subtype name with a reference
3965 -- to the formal of the predicate function. N can be an identifier
3966 -- referencing the subtype, or a selected component, representing an
3967 -- appropriately qualified occurrence of the subtype name.
3969 procedure Replace_Type_References is
3970 new Replace_Type_References_Generic (Replace_Type_Reference);
3971 -- Traverse an expression changing every occurrence of an identifier
3972 -- whose name matches the name of the subtype with a reference to
3973 -- the formal parameter of the predicate function.
3975 ----------------------------
3976 -- Replace_Type_Reference --
3977 ----------------------------
3979 procedure Replace_Type_Reference (N : Node_Id) is
3981 Rewrite (N, Make_Identifier (Loc, Object_Name));
3982 Set_Entity (N, Object_Entity);
3984 end Replace_Type_Reference;
3986 -- Start of processing for Add_Predicates
3989 Ritem := First_Rep_Item (Typ);
3990 while Present (Ritem) loop
3991 if Nkind (Ritem) = N_Pragma
3992 and then Pragma_Name (Ritem) = Name_Predicate
3994 if From_Dynamic_Predicate (Ritem) then
3995 Dynamic_Predicate_Present := True;
3996 elsif From_Static_Predicate (Ritem) then
3997 Static_Predicate_Present := Ritem;
4000 -- Acquire arguments
4002 Arg1 := First (Pragma_Argument_Associations (Ritem));
4003 Arg2 := Next (Arg1);
4005 Arg1 := Get_Pragma_Arg (Arg1);
4006 Arg2 := Get_Pragma_Arg (Arg2);
4008 -- See if this predicate pragma is for the current type
4010 if Entity (Arg1) = Typ then
4012 -- We have a match, this entry is for our subtype
4014 -- We need to replace any occurrences of the name of the
4015 -- type with references to the object.
4017 Replace_Type_References (Arg2, Chars (Typ));
4019 -- If this predicate comes from an aspect, find the aspect
4020 -- specification, and replace the saved expression because
4021 -- we need the subtype references replaced for the calls to
4022 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4023 -- and Check_Aspect_At_End_Of_Declarations.
4025 if From_Aspect_Specification (Ritem) then
4030 -- Loop to find corresponding aspect, note that this
4031 -- must be present given the pragma is marked delayed.
4033 Aitem := Next_Rep_Item (Ritem);
4035 if Nkind (Aitem) = N_Aspect_Specification
4036 and then Aspect_Rep_Item (Aitem) = Ritem
4039 (Identifier (Aitem), New_Copy_Tree (Arg2));
4043 Aitem := Next_Rep_Item (Aitem);
4048 -- Now we can add the expression
4051 Expr := Relocate_Node (Arg2);
4053 -- There already was a predicate, so add to it
4058 Left_Opnd => Relocate_Node (Expr),
4059 Right_Opnd => Relocate_Node (Arg2));
4064 Next_Rep_Item (Ritem);
4068 -- Start of processing for Build_Predicate_Function
4071 -- Initialize for construction of statement list
4075 -- Return if already built or if type does not have predicates
4077 if not Has_Predicates (Typ)
4078 or else Present (Predicate_Function (Typ))
4083 -- Add Predicates for the current type
4087 -- Add predicates for ancestor if present
4090 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4092 if Present (Atyp) then
4097 -- If we have predicates, build the function
4099 if Present (Expr) then
4101 -- Build function declaration
4103 pragma Assert (Has_Predicates (Typ));
4105 Make_Defining_Identifier (Loc,
4106 Chars => New_External_Name (Chars (Typ), "Predicate"));
4107 Set_Has_Predicates (SId);
4108 Set_Predicate_Function (Typ, SId);
4111 Make_Function_Specification (Loc,
4112 Defining_Unit_Name => SId,
4113 Parameter_Specifications => New_List (
4114 Make_Parameter_Specification (Loc,
4115 Defining_Identifier => Object_Entity,
4116 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4117 Result_Definition =>
4118 New_Occurrence_Of (Standard_Boolean, Loc));
4120 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4122 -- Build function body
4125 Make_Defining_Identifier (Loc,
4126 Chars => New_External_Name (Chars (Typ), "Predicate"));
4129 Make_Function_Specification (Loc,
4130 Defining_Unit_Name => SId,
4131 Parameter_Specifications => New_List (
4132 Make_Parameter_Specification (Loc,
4133 Defining_Identifier =>
4134 Make_Defining_Identifier (Loc, Object_Name),
4136 New_Occurrence_Of (Typ, Loc))),
4137 Result_Definition =>
4138 New_Occurrence_Of (Standard_Boolean, Loc));
4141 Make_Subprogram_Body (Loc,
4142 Specification => Spec,
4143 Declarations => Empty_List,
4144 Handled_Statement_Sequence =>
4145 Make_Handled_Sequence_Of_Statements (Loc,
4146 Statements => New_List (
4147 Make_Simple_Return_Statement (Loc,
4148 Expression => Expr))));
4150 -- Insert declaration before freeze node and body after
4152 Insert_Before_And_Analyze (N, FDecl);
4153 Insert_After_And_Analyze (N, FBody);
4155 -- Deal with static predicate case
4157 if Ekind_In (Typ, E_Enumeration_Subtype,
4158 E_Modular_Integer_Subtype,
4159 E_Signed_Integer_Subtype)
4160 and then Is_Static_Subtype (Typ)
4161 and then not Dynamic_Predicate_Present
4163 Build_Static_Predicate (Typ, Expr, Object_Name);
4165 if Present (Static_Predicate_Present)
4166 and No (Static_Predicate (Typ))
4169 ("expression does not have required form for "
4170 & "static predicate",
4171 Next (First (Pragma_Argument_Associations
4172 (Static_Predicate_Present))));
4176 end Build_Predicate_Function;
4178 ----------------------------
4179 -- Build_Static_Predicate --
4180 ----------------------------
4182 procedure Build_Static_Predicate
4187 Loc : constant Source_Ptr := Sloc (Expr);
4189 Non_Static : exception;
4190 -- Raised if something non-static is found
4192 Btyp : constant Entity_Id := Base_Type (Typ);
4194 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4195 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4196 -- Low bound and high bound value of base type of Typ
4198 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4199 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4200 -- Low bound and high bound values of static subtype Typ
4205 -- One entry in a Rlist value, a single REnt (range entry) value
4206 -- denotes one range from Lo to Hi. To represent a single value
4207 -- range Lo = Hi = value.
4209 type RList is array (Nat range <>) of REnt;
4210 -- A list of ranges. The ranges are sorted in increasing order,
4211 -- and are disjoint (there is a gap of at least one value between
4212 -- each range in the table). A value is in the set of ranges in
4213 -- Rlist if it lies within one of these ranges
4215 False_Range : constant RList :=
4216 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4217 -- An empty set of ranges represents a range list that can never be
4218 -- satisfied, since there are no ranges in which the value could lie,
4219 -- so it does not lie in any of them. False_Range is a canonical value
4220 -- for this empty set, but general processing should test for an Rlist
4221 -- with length zero (see Is_False predicate), since other null ranges
4222 -- may appear which must be treated as False.
4224 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4225 -- Range representing True, value must be in the base range
4227 function "and" (Left, Right : RList) return RList;
4228 -- And's together two range lists, returning a range list. This is
4229 -- a set intersection operation.
4231 function "or" (Left, Right : RList) return RList;
4232 -- Or's together two range lists, returning a range list. This is a
4233 -- set union operation.
4235 function "not" (Right : RList) return RList;
4236 -- Returns complement of a given range list, i.e. a range list
4237 -- representing all the values in TLo .. THi that are not in the
4238 -- input operand Right.
4240 function Build_Val (V : Uint) return Node_Id;
4241 -- Return an analyzed N_Identifier node referencing this value, suitable
4242 -- for use as an entry in the Static_Predicate list. This node is typed
4243 -- with the base type.
4245 function Build_Range (Lo, Hi : Uint) return Node_Id;
4246 -- Return an analyzed N_Range node referencing this range, suitable
4247 -- for use as an entry in the Static_Predicate list. This node is typed
4248 -- with the base type.
4250 function Get_RList (Exp : Node_Id) return RList;
4251 -- This is a recursive routine that converts the given expression into
4252 -- a list of ranges, suitable for use in building the static predicate.
4254 function Is_False (R : RList) return Boolean;
4255 pragma Inline (Is_False);
4256 -- Returns True if the given range list is empty, and thus represents
4257 -- a False list of ranges that can never be satisfied.
4259 function Is_True (R : RList) return Boolean;
4260 -- Returns True if R trivially represents the True predicate by having
4261 -- a single range from BLo to BHi.
4263 function Is_Type_Ref (N : Node_Id) return Boolean;
4264 pragma Inline (Is_Type_Ref);
4265 -- Returns if True if N is a reference to the type for the predicate in
4266 -- the expression (i.e. if it is an identifier whose Chars field matches
4267 -- the Nam given in the call).
4269 function Lo_Val (N : Node_Id) return Uint;
4270 -- Given static expression or static range from a Static_Predicate list,
4271 -- gets expression value or low bound of range.
4273 function Hi_Val (N : Node_Id) return Uint;
4274 -- Given static expression or static range from a Static_Predicate list,
4275 -- gets expression value of high bound of range.
4277 function Membership_Entry (N : Node_Id) return RList;
4278 -- Given a single membership entry (range, value, or subtype), returns
4279 -- the corresponding range list. Raises Static_Error if not static.
4281 function Membership_Entries (N : Node_Id) return RList;
4282 -- Given an element on an alternatives list of a membership operation,
4283 -- returns the range list corresponding to this entry and all following
4284 -- entries (i.e. returns the "or" of this list of values).
4286 function Stat_Pred (Typ : Entity_Id) return RList;
4287 -- Given a type, if it has a static predicate, then return the predicate
4288 -- as a range list, otherwise raise Non_Static.
4294 function "and" (Left, Right : RList) return RList is
4296 -- First range of result
4298 SLeft : Nat := Left'First;
4299 -- Start of rest of left entries
4301 SRight : Nat := Right'First;
4302 -- Start of rest of right entries
4305 -- If either range is True, return the other
4307 if Is_True (Left) then
4309 elsif Is_True (Right) then
4313 -- If either range is False, return False
4315 if Is_False (Left) or else Is_False (Right) then
4319 -- Loop to remove entries at start that are disjoint, and thus
4320 -- just get discarded from the result entirely.
4323 -- If no operands left in either operand, result is false
4325 if SLeft > Left'Last or else SRight > Right'Last then
4328 -- Discard first left operand entry if disjoint with right
4330 elsif Left (SLeft).Hi < Right (SRight).Lo then
4333 -- Discard first right operand entry if disjoint with left
4335 elsif Right (SRight).Hi < Left (SLeft).Lo then
4336 SRight := SRight + 1;
4338 -- Otherwise we have an overlapping entry
4345 -- Now we have two non-null operands, and first entries overlap.
4346 -- The first entry in the result will be the overlapping part of
4347 -- these two entries.
4349 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
4350 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
4352 -- Now we can remove the entry that ended at a lower value, since
4353 -- its contribution is entirely contained in Fent.
4355 if Left (SLeft).Hi <= Right (SRight).Hi then
4358 SRight := SRight + 1;
4361 -- Compute result by concatenating this first entry with the "and"
4362 -- of the remaining parts of the left and right operands. Note that
4363 -- if either of these is empty, "and" will yield empty, so that we
4364 -- will end up with just Fent, which is what we want in that case.
4367 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
4374 function "not" (Right : RList) return RList is
4376 -- Return True if False range
4378 if Is_False (Right) then
4382 -- Return False if True range
4384 if Is_True (Right) then
4388 -- Here if not trivial case
4391 Result : RList (1 .. Right'Length + 1);
4392 -- May need one more entry for gap at beginning and end
4395 -- Number of entries stored in Result
4400 if Right (Right'First).Lo > TLo then
4402 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
4405 -- Gaps between ranges
4407 for J in Right'First .. Right'Last - 1 loop
4410 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
4415 if Right (Right'Last).Hi < THi then
4417 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
4420 return Result (1 .. Count);
4428 function "or" (Left, Right : RList) return RList is
4430 -- First range of result
4432 SLeft : Nat := Left'First;
4433 -- Start of rest of left entries
4435 SRight : Nat := Right'First;
4436 -- Start of rest of right entries
4439 -- If either range is True, return True
4441 if Is_True (Left) or else Is_True (Right) then
4445 -- If either range is False (empty), return the other
4447 if Is_False (Left) then
4449 elsif Is_False (Right) then
4453 -- Initialize result first entry from left or right operand
4454 -- depending on which starts with the lower range.
4456 if Left (SLeft).Lo < Right (SRight).Lo then
4457 FEnt := Left (SLeft);
4460 FEnt := Right (SRight);
4461 SRight := SRight + 1;
4464 -- This loop eats ranges from left and right operands that
4465 -- are contiguous with the first range we are gathering.
4468 -- Eat first entry in left operand if contiguous or
4469 -- overlapped by gathered first operand of result.
4471 if SLeft <= Left'Last
4472 and then Left (SLeft).Lo <= FEnt.Hi + 1
4474 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
4477 -- Eat first entry in right operand if contiguous or
4478 -- overlapped by gathered right operand of result.
4480 elsif SRight <= Right'Last
4481 and then Right (SRight).Lo <= FEnt.Hi + 1
4483 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
4484 SRight := SRight + 1;
4486 -- All done if no more entries to eat!
4493 -- Obtain result as the first entry we just computed, concatenated
4494 -- to the "or" of the remaining results (if one operand is empty,
4495 -- this will just concatenate with the other
4498 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
4505 function Build_Range (Lo, Hi : Uint) return Node_Id is
4509 return Build_Val (Hi);
4513 Low_Bound => Build_Val (Lo),
4514 High_Bound => Build_Val (Hi));
4515 Set_Etype (Result, Btyp);
4516 Set_Analyzed (Result);
4525 function Build_Val (V : Uint) return Node_Id is
4529 if Is_Enumeration_Type (Typ) then
4530 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
4532 Result := Make_Integer_Literal (Loc, V);
4535 Set_Etype (Result, Btyp);
4536 Set_Is_Static_Expression (Result);
4537 Set_Analyzed (Result);
4545 function Get_RList (Exp : Node_Id) return RList is
4550 -- Static expression can only be true or false
4552 if Is_OK_Static_Expression (Exp) then
4556 if Expr_Value (Exp) = 0 then
4563 -- Otherwise test node type
4571 when N_Op_And | N_And_Then =>
4572 return Get_RList (Left_Opnd (Exp))
4574 Get_RList (Right_Opnd (Exp));
4578 when N_Op_Or | N_Or_Else =>
4579 return Get_RList (Left_Opnd (Exp))
4581 Get_RList (Right_Opnd (Exp));
4586 return not Get_RList (Right_Opnd (Exp));
4588 -- Comparisons of type with static value
4590 when N_Op_Compare =>
4591 -- Type is left operand
4593 if Is_Type_Ref (Left_Opnd (Exp))
4594 and then Is_OK_Static_Expression (Right_Opnd (Exp))
4596 Val := Expr_Value (Right_Opnd (Exp));
4598 -- Typ is right operand
4600 elsif Is_Type_Ref (Right_Opnd (Exp))
4601 and then Is_OK_Static_Expression (Left_Opnd (Exp))
4603 Val := Expr_Value (Left_Opnd (Exp));
4605 -- Invert sense of comparison
4608 when N_Op_Gt => Op := N_Op_Lt;
4609 when N_Op_Lt => Op := N_Op_Gt;
4610 when N_Op_Ge => Op := N_Op_Le;
4611 when N_Op_Le => Op := N_Op_Ge;
4612 when others => null;
4615 -- Other cases are non-static
4621 -- Construct range according to comparison operation
4625 return RList'(1 => REnt'(Val, Val));
4628 return RList'(1 => REnt'(Val, BHi));
4631 return RList'(1 => REnt'(Val + 1, BHi));
4634 return RList'(1 => REnt'(BLo, Val));
4637 return RList'(1 => REnt'(BLo, Val - 1));
4640 return RList'(REnt'(BLo, Val - 1),
4641 REnt'(Val + 1, BHi));
4644 raise Program_Error;
4650 if not Is_Type_Ref (Left_Opnd (Exp)) then
4654 if Present (Right_Opnd (Exp)) then
4655 return Membership_Entry (Right_Opnd (Exp));
4657 return Membership_Entries (First (Alternatives (Exp)));
4660 -- Negative membership (NOT IN)
4663 if not Is_Type_Ref (Left_Opnd (Exp)) then
4667 if Present (Right_Opnd (Exp)) then
4668 return not Membership_Entry (Right_Opnd (Exp));
4670 return not Membership_Entries (First (Alternatives (Exp)));
4673 -- Function call, may be call to static predicate
4675 when N_Function_Call =>
4676 if Is_Entity_Name (Name (Exp)) then
4678 Ent : constant Entity_Id := Entity (Name (Exp));
4680 if Has_Predicates (Ent) then
4681 return Stat_Pred (Etype (First_Formal (Ent)));
4686 -- Other function call cases are non-static
4690 -- Qualified expression, dig out the expression
4692 when N_Qualified_Expression =>
4693 return Get_RList (Expression (Exp));
4698 return (Get_RList (Left_Opnd (Exp))
4699 and not Get_RList (Right_Opnd (Exp)))
4700 or (Get_RList (Right_Opnd (Exp))
4701 and not Get_RList (Left_Opnd (Exp)));
4703 -- Any other node type is non-static
4714 function Hi_Val (N : Node_Id) return Uint is
4716 if Is_Static_Expression (N) then
4717 return Expr_Value (N);
4719 pragma Assert (Nkind (N) = N_Range);
4720 return Expr_Value (High_Bound (N));
4728 function Is_False (R : RList) return Boolean is
4730 return R'Length = 0;
4737 function Is_True (R : RList) return Boolean is
4740 and then R (R'First).Lo = BLo
4741 and then R (R'First).Hi = BHi;
4748 function Is_Type_Ref (N : Node_Id) return Boolean is
4750 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
4757 function Lo_Val (N : Node_Id) return Uint is
4759 if Is_Static_Expression (N) then
4760 return Expr_Value (N);
4762 pragma Assert (Nkind (N) = N_Range);
4763 return Expr_Value (Low_Bound (N));
4767 ------------------------
4768 -- Membership_Entries --
4769 ------------------------
4771 function Membership_Entries (N : Node_Id) return RList is
4773 if No (Next (N)) then
4774 return Membership_Entry (N);
4776 return Membership_Entry (N) or Membership_Entries (Next (N));
4778 end Membership_Entries;
4780 ----------------------
4781 -- Membership_Entry --
4782 ----------------------
4784 function Membership_Entry (N : Node_Id) return RList is
4792 if Nkind (N) = N_Range then
4793 if not Is_Static_Expression (Low_Bound (N))
4795 not Is_Static_Expression (High_Bound (N))
4799 SLo := Expr_Value (Low_Bound (N));
4800 SHi := Expr_Value (High_Bound (N));
4801 return RList'(1 => REnt'(SLo, SHi));
4804 -- Static expression case
4806 elsif Is_Static_Expression (N) then
4807 Val := Expr_Value (N);
4808 return RList'(1 => REnt'(Val, Val));
4810 -- Identifier (other than static expression) case
4812 else pragma Assert (Nkind (N) = N_Identifier);
4816 if Is_Type (Entity (N)) then
4818 -- If type has predicates, process them
4820 if Has_Predicates (Entity (N)) then
4821 return Stat_Pred (Entity (N));
4823 -- For static subtype without predicates, get range
4825 elsif Is_Static_Subtype (Entity (N)) then
4826 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
4827 SHi := Expr_Value (Type_High_Bound (Entity (N)));
4828 return RList'(1 => REnt'(SLo, SHi));
4830 -- Any other type makes us non-static
4836 -- Any other kind of identifier in predicate (e.g. a non-static
4837 -- expression value) means this is not a static predicate.
4843 end Membership_Entry;
4849 function Stat_Pred (Typ : Entity_Id) return RList is
4851 -- Not static if type does not have static predicates
4853 if not Has_Predicates (Typ)
4854 or else No (Static_Predicate (Typ))
4859 -- Otherwise we convert the predicate list to a range list
4862 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
4866 P := First (Static_Predicate (Typ));
4867 for J in Result'Range loop
4868 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
4876 -- Start of processing for Build_Static_Predicate
4879 -- Now analyze the expression to see if it is a static predicate
4882 Ranges : constant RList := Get_RList (Expr);
4883 -- Range list from expression if it is static
4888 -- Convert range list into a form for the static predicate. In the
4889 -- Ranges array, we just have raw ranges, these must be converted
4890 -- to properly typed and analyzed static expressions or range nodes.
4892 -- Note: here we limit ranges to the ranges of the subtype, so that
4893 -- a predicate is always false for values outside the subtype. That
4894 -- seems fine, such values are invalid anyway, and considering them
4895 -- to fail the predicate seems allowed and friendly, and furthermore
4896 -- simplifies processing for case statements and loops.
4900 for J in Ranges'Range loop
4902 Lo : Uint := Ranges (J).Lo;
4903 Hi : Uint := Ranges (J).Hi;
4906 -- Ignore completely out of range entry
4908 if Hi < TLo or else Lo > THi then
4911 -- Otherwise process entry
4914 -- Adjust out of range value to subtype range
4924 -- Convert range into required form
4927 Append_To (Plist, Build_Val (Lo));
4929 Append_To (Plist, Build_Range (Lo, Hi));
4935 -- Processing was successful and all entries were static, so now we
4936 -- can store the result as the predicate list.
4938 Set_Static_Predicate (Typ, Plist);
4940 -- The processing for static predicates put the expression into
4941 -- canonical form as a series of ranges. It also eliminated
4942 -- duplicates and collapsed and combined ranges. We might as well
4943 -- replace the alternatives list of the right operand of the
4944 -- membership test with the static predicate list, which will
4945 -- usually be more efficient.
4948 New_Alts : constant List_Id := New_List;
4953 Old_Node := First (Plist);
4954 while Present (Old_Node) loop
4955 New_Node := New_Copy (Old_Node);
4957 if Nkind (New_Node) = N_Range then
4958 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
4959 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
4962 Append_To (New_Alts, New_Node);
4966 -- If empty list, replace by False
4968 if Is_Empty_List (New_Alts) then
4969 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
4971 -- Else replace by set membership test
4976 Left_Opnd => Make_Identifier (Loc, Nam),
4977 Right_Opnd => Empty,
4978 Alternatives => New_Alts));
4980 -- Resolve new expression in function context
4982 Install_Formals (Predicate_Function (Typ));
4983 Push_Scope (Predicate_Function (Typ));
4984 Analyze_And_Resolve (Expr, Standard_Boolean);
4990 -- If non-static, return doing nothing
4995 end Build_Static_Predicate;
4997 -----------------------------------------
4998 -- Check_Aspect_At_End_Of_Declarations --
4999 -----------------------------------------
5001 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5002 Ent : constant Entity_Id := Entity (ASN);
5003 Ident : constant Node_Id := Identifier (ASN);
5005 Freeze_Expr : constant Node_Id := Expression (ASN);
5006 -- Preanalyzed expression from call to Check_Aspect_At_Freeze_Point
5008 End_Decl_Expr : constant Node_Id := Entity (Ident);
5009 -- Expression to be analyzed at end of declarations
5011 T : constant Entity_Id := Etype (Freeze_Expr);
5012 -- Type required for preanalyze call
5014 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5017 -- Set False if error
5019 -- On entry to this procedure, Entity (Ident) contains a copy of the
5020 -- original expression from the aspect, saved for this purpose, and
5021 -- but Expression (Ident) is a preanalyzed copy of the expression,
5022 -- preanalyzed just after the freeze point.
5025 -- Case of stream attributes, just have to compare entities
5027 if A_Id = Aspect_Input or else
5028 A_Id = Aspect_Output or else
5029 A_Id = Aspect_Read or else
5032 Analyze (End_Decl_Expr);
5033 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5038 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5039 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5042 -- Output error message if error
5046 ("visibility of aspect for& changes after freeze point",
5049 ("?info: & is frozen here, aspects evaluated at this point",
5050 Freeze_Node (Ent), Ent);
5052 end Check_Aspect_At_End_Of_Declarations;
5054 ----------------------------------
5055 -- Check_Aspect_At_Freeze_Point --
5056 ----------------------------------
5058 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5059 Ident : constant Node_Id := Identifier (ASN);
5060 -- Identifier (use Entity field to save expression)
5063 -- Type required for preanalyze call
5065 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5068 -- On entry to this procedure, Entity (Ident) contains a copy of the
5069 -- original expression from the aspect, saved for this purpose.
5071 -- On exit from this procedure Entity (Ident) is unchanged, still
5072 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5073 -- of the expression, preanalyzed just after the freeze point.
5075 -- Make a copy of the expression to be preanalyed
5077 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5079 -- Find type for preanalyze call
5083 -- No_Aspect should be impossible
5086 raise Program_Error;
5088 -- Aspects taking an optional boolean argument. Note that we will
5089 -- never be called with an empty expression, because such aspects
5090 -- never need to be delayed anyway.
5092 when Boolean_Aspects =>
5093 pragma Assert (Present (Expression (ASN)));
5094 T := Standard_Boolean;
5096 -- Aspects corresponding to attribute definition clauses
5098 when Aspect_Address =>
5099 T := RTE (RE_Address);
5101 when Aspect_Bit_Order =>
5102 T := RTE (RE_Bit_Order);
5104 when Aspect_External_Tag =>
5105 T := Standard_String;
5107 when Aspect_Storage_Pool =>
5108 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5112 Aspect_Component_Size |
5113 Aspect_Machine_Radix |
5114 Aspect_Object_Size |
5116 Aspect_Storage_Size |
5117 Aspect_Stream_Size |
5118 Aspect_Value_Size =>
5121 -- Stream attribute. Special case, the expression is just an entity
5122 -- that does not need any resolution, so just analyze.
5128 Analyze (Expression (ASN));
5131 -- Suppress/Unsupress/Warnings should never be delayed
5133 when Aspect_Suppress |
5136 raise Program_Error;
5138 -- Pre/Post/Invariant/Predicate take boolean expressions
5140 when Aspect_Dynamic_Predicate |
5143 Aspect_Precondition |
5145 Aspect_Postcondition |
5147 Aspect_Static_Predicate |
5148 Aspect_Type_Invariant =>
5149 T := Standard_Boolean;
5152 -- Do the preanalyze call
5154 Preanalyze_Spec_Expression (Expression (ASN), T);
5155 end Check_Aspect_At_Freeze_Point;
5157 -----------------------------------
5158 -- Check_Constant_Address_Clause --
5159 -----------------------------------
5161 procedure Check_Constant_Address_Clause
5165 procedure Check_At_Constant_Address (Nod : Node_Id);
5166 -- Checks that the given node N represents a name whose 'Address is
5167 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5168 -- address value is the same at the point of declaration of U_Ent and at
5169 -- the time of elaboration of the address clause.
5171 procedure Check_Expr_Constants (Nod : Node_Id);
5172 -- Checks that Nod meets the requirements for a constant address clause
5173 -- in the sense of the enclosing procedure.
5175 procedure Check_List_Constants (Lst : List_Id);
5176 -- Check that all elements of list Lst meet the requirements for a
5177 -- constant address clause in the sense of the enclosing procedure.
5179 -------------------------------
5180 -- Check_At_Constant_Address --
5181 -------------------------------
5183 procedure Check_At_Constant_Address (Nod : Node_Id) is
5185 if Is_Entity_Name (Nod) then
5186 if Present (Address_Clause (Entity ((Nod)))) then
5188 ("invalid address clause for initialized object &!",
5191 ("address for& cannot" &
5192 " depend on another address clause! (RM 13.1(22))!",
5195 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
5196 and then Sloc (U_Ent) < Sloc (Entity (Nod))
5199 ("invalid address clause for initialized object &!",
5201 Error_Msg_Node_2 := U_Ent;
5203 ("\& must be defined before & (RM 13.1(22))!",
5207 elsif Nkind (Nod) = N_Selected_Component then
5209 T : constant Entity_Id := Etype (Prefix (Nod));
5212 if (Is_Record_Type (T)
5213 and then Has_Discriminants (T))
5216 and then Is_Record_Type (Designated_Type (T))
5217 and then Has_Discriminants (Designated_Type (T)))
5220 ("invalid address clause for initialized object &!",
5223 ("\address cannot depend on component" &
5224 " of discriminated record (RM 13.1(22))!",
5227 Check_At_Constant_Address (Prefix (Nod));
5231 elsif Nkind (Nod) = N_Indexed_Component then
5232 Check_At_Constant_Address (Prefix (Nod));
5233 Check_List_Constants (Expressions (Nod));
5236 Check_Expr_Constants (Nod);
5238 end Check_At_Constant_Address;
5240 --------------------------
5241 -- Check_Expr_Constants --
5242 --------------------------
5244 procedure Check_Expr_Constants (Nod : Node_Id) is
5245 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
5246 Ent : Entity_Id := Empty;
5249 if Nkind (Nod) in N_Has_Etype
5250 and then Etype (Nod) = Any_Type
5256 when N_Empty | N_Error =>
5259 when N_Identifier | N_Expanded_Name =>
5260 Ent := Entity (Nod);
5262 -- We need to look at the original node if it is different
5263 -- from the node, since we may have rewritten things and
5264 -- substituted an identifier representing the rewrite.
5266 if Original_Node (Nod) /= Nod then
5267 Check_Expr_Constants (Original_Node (Nod));
5269 -- If the node is an object declaration without initial
5270 -- value, some code has been expanded, and the expression
5271 -- is not constant, even if the constituents might be
5272 -- acceptable, as in A'Address + offset.
5274 if Ekind (Ent) = E_Variable
5276 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
5278 No (Expression (Declaration_Node (Ent)))
5281 ("invalid address clause for initialized object &!",
5284 -- If entity is constant, it may be the result of expanding
5285 -- a check. We must verify that its declaration appears
5286 -- before the object in question, else we also reject the
5289 elsif Ekind (Ent) = E_Constant
5290 and then In_Same_Source_Unit (Ent, U_Ent)
5291 and then Sloc (Ent) > Loc_U_Ent
5294 ("invalid address clause for initialized object &!",
5301 -- Otherwise look at the identifier and see if it is OK
5303 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
5304 or else Is_Type (Ent)
5309 Ekind (Ent) = E_Constant
5311 Ekind (Ent) = E_In_Parameter
5313 -- This is the case where we must have Ent defined before
5314 -- U_Ent. Clearly if they are in different units this
5315 -- requirement is met since the unit containing Ent is
5316 -- already processed.
5318 if not In_Same_Source_Unit (Ent, U_Ent) then
5321 -- Otherwise location of Ent must be before the location
5322 -- of U_Ent, that's what prior defined means.
5324 elsif Sloc (Ent) < Loc_U_Ent then
5329 ("invalid address clause for initialized object &!",
5331 Error_Msg_Node_2 := U_Ent;
5333 ("\& must be defined before & (RM 13.1(22))!",
5337 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
5338 Check_Expr_Constants (Original_Node (Nod));
5342 ("invalid address clause for initialized object &!",
5345 if Comes_From_Source (Ent) then
5347 ("\reference to variable& not allowed"
5348 & " (RM 13.1(22))!", Nod, Ent);
5351 ("non-static expression not allowed"
5352 & " (RM 13.1(22))!", Nod);
5356 when N_Integer_Literal =>
5358 -- If this is a rewritten unchecked conversion, in a system
5359 -- where Address is an integer type, always use the base type
5360 -- for a literal value. This is user-friendly and prevents
5361 -- order-of-elaboration issues with instances of unchecked
5364 if Nkind (Original_Node (Nod)) = N_Function_Call then
5365 Set_Etype (Nod, Base_Type (Etype (Nod)));
5368 when N_Real_Literal |
5370 N_Character_Literal =>
5374 Check_Expr_Constants (Low_Bound (Nod));
5375 Check_Expr_Constants (High_Bound (Nod));
5377 when N_Explicit_Dereference =>
5378 Check_Expr_Constants (Prefix (Nod));
5380 when N_Indexed_Component =>
5381 Check_Expr_Constants (Prefix (Nod));
5382 Check_List_Constants (Expressions (Nod));
5385 Check_Expr_Constants (Prefix (Nod));
5386 Check_Expr_Constants (Discrete_Range (Nod));
5388 when N_Selected_Component =>
5389 Check_Expr_Constants (Prefix (Nod));
5391 when N_Attribute_Reference =>
5392 if Attribute_Name (Nod) = Name_Address
5394 Attribute_Name (Nod) = Name_Access
5396 Attribute_Name (Nod) = Name_Unchecked_Access
5398 Attribute_Name (Nod) = Name_Unrestricted_Access
5400 Check_At_Constant_Address (Prefix (Nod));
5403 Check_Expr_Constants (Prefix (Nod));
5404 Check_List_Constants (Expressions (Nod));
5408 Check_List_Constants (Component_Associations (Nod));
5409 Check_List_Constants (Expressions (Nod));
5411 when N_Component_Association =>
5412 Check_Expr_Constants (Expression (Nod));
5414 when N_Extension_Aggregate =>
5415 Check_Expr_Constants (Ancestor_Part (Nod));
5416 Check_List_Constants (Component_Associations (Nod));
5417 Check_List_Constants (Expressions (Nod));
5422 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
5423 Check_Expr_Constants (Left_Opnd (Nod));
5424 Check_Expr_Constants (Right_Opnd (Nod));
5427 Check_Expr_Constants (Right_Opnd (Nod));
5429 when N_Type_Conversion |
5430 N_Qualified_Expression |
5432 Check_Expr_Constants (Expression (Nod));
5434 when N_Unchecked_Type_Conversion =>
5435 Check_Expr_Constants (Expression (Nod));
5437 -- If this is a rewritten unchecked conversion, subtypes in
5438 -- this node are those created within the instance. To avoid
5439 -- order of elaboration issues, replace them with their base
5440 -- types. Note that address clauses can cause order of
5441 -- elaboration problems because they are elaborated by the
5442 -- back-end at the point of definition, and may mention
5443 -- entities declared in between (as long as everything is
5444 -- static). It is user-friendly to allow unchecked conversions
5447 if Nkind (Original_Node (Nod)) = N_Function_Call then
5448 Set_Etype (Expression (Nod),
5449 Base_Type (Etype (Expression (Nod))));
5450 Set_Etype (Nod, Base_Type (Etype (Nod)));
5453 when N_Function_Call =>
5454 if not Is_Pure (Entity (Name (Nod))) then
5456 ("invalid address clause for initialized object &!",
5460 ("\function & is not pure (RM 13.1(22))!",
5461 Nod, Entity (Name (Nod)));
5464 Check_List_Constants (Parameter_Associations (Nod));
5467 when N_Parameter_Association =>
5468 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
5472 ("invalid address clause for initialized object &!",
5475 ("\must be constant defined before& (RM 13.1(22))!",
5478 end Check_Expr_Constants;
5480 --------------------------
5481 -- Check_List_Constants --
5482 --------------------------
5484 procedure Check_List_Constants (Lst : List_Id) is
5488 if Present (Lst) then
5489 Nod1 := First (Lst);
5490 while Present (Nod1) loop
5491 Check_Expr_Constants (Nod1);
5495 end Check_List_Constants;
5497 -- Start of processing for Check_Constant_Address_Clause
5500 -- If rep_clauses are to be ignored, no need for legality checks. In
5501 -- particular, no need to pester user about rep clauses that violate
5502 -- the rule on constant addresses, given that these clauses will be
5503 -- removed by Freeze before they reach the back end.
5505 if not Ignore_Rep_Clauses then
5506 Check_Expr_Constants (Expr);
5508 end Check_Constant_Address_Clause;
5510 ----------------------------------------
5511 -- Check_Record_Representation_Clause --
5512 ----------------------------------------
5514 procedure Check_Record_Representation_Clause (N : Node_Id) is
5515 Loc : constant Source_Ptr := Sloc (N);
5516 Ident : constant Node_Id := Identifier (N);
5517 Rectype : Entity_Id;
5522 Hbit : Uint := Uint_0;
5526 Max_Bit_So_Far : Uint;
5527 -- Records the maximum bit position so far. If all field positions
5528 -- are monotonically increasing, then we can skip the circuit for
5529 -- checking for overlap, since no overlap is possible.
5531 Tagged_Parent : Entity_Id := Empty;
5532 -- This is set in the case of a derived tagged type for which we have
5533 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
5534 -- positioned by record representation clauses). In this case we must
5535 -- check for overlap between components of this tagged type, and the
5536 -- components of its parent. Tagged_Parent will point to this parent
5537 -- type. For all other cases Tagged_Parent is left set to Empty.
5539 Parent_Last_Bit : Uint;
5540 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
5541 -- last bit position for any field in the parent type. We only need to
5542 -- check overlap for fields starting below this point.
5544 Overlap_Check_Required : Boolean;
5545 -- Used to keep track of whether or not an overlap check is required
5547 Overlap_Detected : Boolean := False;
5548 -- Set True if an overlap is detected
5550 Ccount : Natural := 0;
5551 -- Number of component clauses in record rep clause
5553 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
5554 -- Given two entities for record components or discriminants, checks
5555 -- if they have overlapping component clauses and issues errors if so.
5557 procedure Find_Component;
5558 -- Finds component entity corresponding to current component clause (in
5559 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
5560 -- start/stop bits for the field. If there is no matching component or
5561 -- if the matching component does not have a component clause, then
5562 -- that's an error and Comp is set to Empty, but no error message is
5563 -- issued, since the message was already given. Comp is also set to
5564 -- Empty if the current "component clause" is in fact a pragma.
5566 -----------------------------
5567 -- Check_Component_Overlap --
5568 -----------------------------
5570 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
5571 CC1 : constant Node_Id := Component_Clause (C1_Ent);
5572 CC2 : constant Node_Id := Component_Clause (C2_Ent);
5575 if Present (CC1) and then Present (CC2) then
5577 -- Exclude odd case where we have two tag fields in the same
5578 -- record, both at location zero. This seems a bit strange, but
5579 -- it seems to happen in some circumstances, perhaps on an error.
5581 if Chars (C1_Ent) = Name_uTag
5583 Chars (C2_Ent) = Name_uTag
5588 -- Here we check if the two fields overlap
5591 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
5592 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
5593 E1 : constant Uint := S1 + Esize (C1_Ent);
5594 E2 : constant Uint := S2 + Esize (C2_Ent);
5597 if E2 <= S1 or else E1 <= S2 then
5600 Error_Msg_Node_2 := Component_Name (CC2);
5601 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
5602 Error_Msg_Node_1 := Component_Name (CC1);
5604 ("component& overlaps & #", Component_Name (CC1));
5605 Overlap_Detected := True;
5609 end Check_Component_Overlap;
5611 --------------------
5612 -- Find_Component --
5613 --------------------
5615 procedure Find_Component is
5617 procedure Search_Component (R : Entity_Id);
5618 -- Search components of R for a match. If found, Comp is set.
5620 ----------------------
5621 -- Search_Component --
5622 ----------------------
5624 procedure Search_Component (R : Entity_Id) is
5626 Comp := First_Component_Or_Discriminant (R);
5627 while Present (Comp) loop
5629 -- Ignore error of attribute name for component name (we
5630 -- already gave an error message for this, so no need to
5633 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
5636 exit when Chars (Comp) = Chars (Component_Name (CC));
5639 Next_Component_Or_Discriminant (Comp);
5641 end Search_Component;
5643 -- Start of processing for Find_Component
5646 -- Return with Comp set to Empty if we have a pragma
5648 if Nkind (CC) = N_Pragma then
5653 -- Search current record for matching component
5655 Search_Component (Rectype);
5657 -- If not found, maybe component of base type that is absent from
5658 -- statically constrained first subtype.
5661 Search_Component (Base_Type (Rectype));
5664 -- If no component, or the component does not reference the component
5665 -- clause in question, then there was some previous error for which
5666 -- we already gave a message, so just return with Comp Empty.
5669 or else Component_Clause (Comp) /= CC
5673 -- Normal case where we have a component clause
5676 Fbit := Component_Bit_Offset (Comp);
5677 Lbit := Fbit + Esize (Comp) - 1;
5681 -- Start of processing for Check_Record_Representation_Clause
5685 Rectype := Entity (Ident);
5687 if Rectype = Any_Type then
5690 Rectype := Underlying_Type (Rectype);
5693 -- See if we have a fully repped derived tagged type
5696 PS : constant Entity_Id := Parent_Subtype (Rectype);
5699 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
5700 Tagged_Parent := PS;
5702 -- Find maximum bit of any component of the parent type
5704 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
5705 Pcomp := First_Entity (Tagged_Parent);
5706 while Present (Pcomp) loop
5707 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
5708 if Component_Bit_Offset (Pcomp) /= No_Uint
5709 and then Known_Static_Esize (Pcomp)
5714 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
5717 Next_Entity (Pcomp);
5723 -- All done if no component clauses
5725 CC := First (Component_Clauses (N));
5731 -- If a tag is present, then create a component clause that places it
5732 -- at the start of the record (otherwise gigi may place it after other
5733 -- fields that have rep clauses).
5735 Fent := First_Entity (Rectype);
5737 if Nkind (Fent) = N_Defining_Identifier
5738 and then Chars (Fent) = Name_uTag
5740 Set_Component_Bit_Offset (Fent, Uint_0);
5741 Set_Normalized_Position (Fent, Uint_0);
5742 Set_Normalized_First_Bit (Fent, Uint_0);
5743 Set_Normalized_Position_Max (Fent, Uint_0);
5744 Init_Esize (Fent, System_Address_Size);
5746 Set_Component_Clause (Fent,
5747 Make_Component_Clause (Loc,
5748 Component_Name => Make_Identifier (Loc, Name_uTag),
5750 Position => Make_Integer_Literal (Loc, Uint_0),
5751 First_Bit => Make_Integer_Literal (Loc, Uint_0),
5753 Make_Integer_Literal (Loc,
5754 UI_From_Int (System_Address_Size))));
5756 Ccount := Ccount + 1;
5759 Max_Bit_So_Far := Uint_Minus_1;
5760 Overlap_Check_Required := False;
5762 -- Process the component clauses
5764 while Present (CC) loop
5767 if Present (Comp) then
5768 Ccount := Ccount + 1;
5770 -- We need a full overlap check if record positions non-monotonic
5772 if Fbit <= Max_Bit_So_Far then
5773 Overlap_Check_Required := True;
5776 Max_Bit_So_Far := Lbit;
5778 -- Check bit position out of range of specified size
5780 if Has_Size_Clause (Rectype)
5781 and then Esize (Rectype) <= Lbit
5784 ("bit number out of range of specified size",
5787 -- Check for overlap with tag field
5790 if Is_Tagged_Type (Rectype)
5791 and then Fbit < System_Address_Size
5794 ("component overlaps tag field of&",
5795 Component_Name (CC), Rectype);
5796 Overlap_Detected := True;
5804 -- Check parent overlap if component might overlap parent field
5806 if Present (Tagged_Parent)
5807 and then Fbit <= Parent_Last_Bit
5809 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
5810 while Present (Pcomp) loop
5811 if not Is_Tag (Pcomp)
5812 and then Chars (Pcomp) /= Name_uParent
5814 Check_Component_Overlap (Comp, Pcomp);
5817 Next_Component_Or_Discriminant (Pcomp);
5825 -- Now that we have processed all the component clauses, check for
5826 -- overlap. We have to leave this till last, since the components can
5827 -- appear in any arbitrary order in the representation clause.
5829 -- We do not need this check if all specified ranges were monotonic,
5830 -- as recorded by Overlap_Check_Required being False at this stage.
5832 -- This first section checks if there are any overlapping entries at
5833 -- all. It does this by sorting all entries and then seeing if there are
5834 -- any overlaps. If there are none, then that is decisive, but if there
5835 -- are overlaps, they may still be OK (they may result from fields in
5836 -- different variants).
5838 if Overlap_Check_Required then
5839 Overlap_Check1 : declare
5841 OC_Fbit : array (0 .. Ccount) of Uint;
5842 -- First-bit values for component clauses, the value is the offset
5843 -- of the first bit of the field from start of record. The zero
5844 -- entry is for use in sorting.
5846 OC_Lbit : array (0 .. Ccount) of Uint;
5847 -- Last-bit values for component clauses, the value is the offset
5848 -- of the last bit of the field from start of record. The zero
5849 -- entry is for use in sorting.
5851 OC_Count : Natural := 0;
5852 -- Count of entries in OC_Fbit and OC_Lbit
5854 function OC_Lt (Op1, Op2 : Natural) return Boolean;
5855 -- Compare routine for Sort
5857 procedure OC_Move (From : Natural; To : Natural);
5858 -- Move routine for Sort
5860 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
5866 function OC_Lt (Op1, Op2 : Natural) return Boolean is
5868 return OC_Fbit (Op1) < OC_Fbit (Op2);
5875 procedure OC_Move (From : Natural; To : Natural) is
5877 OC_Fbit (To) := OC_Fbit (From);
5878 OC_Lbit (To) := OC_Lbit (From);
5881 -- Start of processing for Overlap_Check
5884 CC := First (Component_Clauses (N));
5885 while Present (CC) loop
5887 -- Exclude component clause already marked in error
5889 if not Error_Posted (CC) then
5892 if Present (Comp) then
5893 OC_Count := OC_Count + 1;
5894 OC_Fbit (OC_Count) := Fbit;
5895 OC_Lbit (OC_Count) := Lbit;
5902 Sorting.Sort (OC_Count);
5904 Overlap_Check_Required := False;
5905 for J in 1 .. OC_Count - 1 loop
5906 if OC_Lbit (J) >= OC_Fbit (J + 1) then
5907 Overlap_Check_Required := True;
5914 -- If Overlap_Check_Required is still True, then we have to do the full
5915 -- scale overlap check, since we have at least two fields that do
5916 -- overlap, and we need to know if that is OK since they are in
5917 -- different variant, or whether we have a definite problem.
5919 if Overlap_Check_Required then
5920 Overlap_Check2 : declare
5921 C1_Ent, C2_Ent : Entity_Id;
5922 -- Entities of components being checked for overlap
5925 -- Component_List node whose Component_Items are being checked
5928 -- Component declaration for component being checked
5931 C1_Ent := First_Entity (Base_Type (Rectype));
5933 -- Loop through all components in record. For each component check
5934 -- for overlap with any of the preceding elements on the component
5935 -- list containing the component and also, if the component is in
5936 -- a variant, check against components outside the case structure.
5937 -- This latter test is repeated recursively up the variant tree.
5939 Main_Component_Loop : while Present (C1_Ent) loop
5940 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
5941 goto Continue_Main_Component_Loop;
5944 -- Skip overlap check if entity has no declaration node. This
5945 -- happens with discriminants in constrained derived types.
5946 -- Possibly we are missing some checks as a result, but that
5947 -- does not seem terribly serious.
5949 if No (Declaration_Node (C1_Ent)) then
5950 goto Continue_Main_Component_Loop;
5953 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
5955 -- Loop through component lists that need checking. Check the
5956 -- current component list and all lists in variants above us.
5958 Component_List_Loop : loop
5960 -- If derived type definition, go to full declaration
5961 -- If at outer level, check discriminants if there are any.
5963 if Nkind (Clist) = N_Derived_Type_Definition then
5964 Clist := Parent (Clist);
5967 -- Outer level of record definition, check discriminants
5969 if Nkind_In (Clist, N_Full_Type_Declaration,
5970 N_Private_Type_Declaration)
5972 if Has_Discriminants (Defining_Identifier (Clist)) then
5974 First_Discriminant (Defining_Identifier (Clist));
5975 while Present (C2_Ent) loop
5976 exit when C1_Ent = C2_Ent;
5977 Check_Component_Overlap (C1_Ent, C2_Ent);
5978 Next_Discriminant (C2_Ent);
5982 -- Record extension case
5984 elsif Nkind (Clist) = N_Derived_Type_Definition then
5987 -- Otherwise check one component list
5990 Citem := First (Component_Items (Clist));
5991 while Present (Citem) loop
5992 if Nkind (Citem) = N_Component_Declaration then
5993 C2_Ent := Defining_Identifier (Citem);
5994 exit when C1_Ent = C2_Ent;
5995 Check_Component_Overlap (C1_Ent, C2_Ent);
6002 -- Check for variants above us (the parent of the Clist can
6003 -- be a variant, in which case its parent is a variant part,
6004 -- and the parent of the variant part is a component list
6005 -- whose components must all be checked against the current
6006 -- component for overlap).
6008 if Nkind (Parent (Clist)) = N_Variant then
6009 Clist := Parent (Parent (Parent (Clist)));
6011 -- Check for possible discriminant part in record, this
6012 -- is treated essentially as another level in the
6013 -- recursion. For this case the parent of the component
6014 -- list is the record definition, and its parent is the
6015 -- full type declaration containing the discriminant
6018 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6019 Clist := Parent (Parent ((Clist)));
6021 -- If neither of these two cases, we are at the top of
6025 exit Component_List_Loop;
6027 end loop Component_List_Loop;
6029 <<Continue_Main_Component_Loop>>
6030 Next_Entity (C1_Ent);
6032 end loop Main_Component_Loop;
6036 -- The following circuit deals with warning on record holes (gaps). We
6037 -- skip this check if overlap was detected, since it makes sense for the
6038 -- programmer to fix this illegality before worrying about warnings.
6040 if not Overlap_Detected and Warn_On_Record_Holes then
6041 Record_Hole_Check : declare
6042 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6043 -- Full declaration of record type
6045 procedure Check_Component_List
6049 -- Check component list CL for holes. The starting bit should be
6050 -- Sbit. which is zero for the main record component list and set
6051 -- appropriately for recursive calls for variants. DS is set to
6052 -- a list of discriminant specifications to be included in the
6053 -- consideration of components. It is No_List if none to consider.
6055 --------------------------
6056 -- Check_Component_List --
6057 --------------------------
6059 procedure Check_Component_List
6067 Compl := Integer (List_Length (Component_Items (CL)));
6069 if DS /= No_List then
6070 Compl := Compl + Integer (List_Length (DS));
6074 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6075 -- Gather components (zero entry is for sort routine)
6077 Ncomps : Natural := 0;
6078 -- Number of entries stored in Comps (starting at Comps (1))
6081 -- One component item or discriminant specification
6084 -- Starting bit for next component
6092 function Lt (Op1, Op2 : Natural) return Boolean;
6093 -- Compare routine for Sort
6095 procedure Move (From : Natural; To : Natural);
6096 -- Move routine for Sort
6098 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6104 function Lt (Op1, Op2 : Natural) return Boolean is
6106 return Component_Bit_Offset (Comps (Op1))
6108 Component_Bit_Offset (Comps (Op2));
6115 procedure Move (From : Natural; To : Natural) is
6117 Comps (To) := Comps (From);
6121 -- Gather discriminants into Comp
6123 if DS /= No_List then
6124 Citem := First (DS);
6125 while Present (Citem) loop
6126 if Nkind (Citem) = N_Discriminant_Specification then
6128 Ent : constant Entity_Id :=
6129 Defining_Identifier (Citem);
6131 if Ekind (Ent) = E_Discriminant then
6132 Ncomps := Ncomps + 1;
6133 Comps (Ncomps) := Ent;
6142 -- Gather component entities into Comp
6144 Citem := First (Component_Items (CL));
6145 while Present (Citem) loop
6146 if Nkind (Citem) = N_Component_Declaration then
6147 Ncomps := Ncomps + 1;
6148 Comps (Ncomps) := Defining_Identifier (Citem);
6154 -- Now sort the component entities based on the first bit.
6155 -- Note we already know there are no overlapping components.
6157 Sorting.Sort (Ncomps);
6159 -- Loop through entries checking for holes
6162 for J in 1 .. Ncomps loop
6164 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6166 if Error_Msg_Uint_1 > 0 then
6168 ("?^-bit gap before component&",
6169 Component_Name (Component_Clause (CEnt)), CEnt);
6172 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
6175 -- Process variant parts recursively if present
6177 if Present (Variant_Part (CL)) then
6178 Variant := First (Variants (Variant_Part (CL)));
6179 while Present (Variant) loop
6180 Check_Component_List
6181 (Component_List (Variant), Nbit, No_List);
6186 end Check_Component_List;
6188 -- Start of processing for Record_Hole_Check
6195 if Is_Tagged_Type (Rectype) then
6196 Sbit := UI_From_Int (System_Address_Size);
6201 if Nkind (Decl) = N_Full_Type_Declaration
6202 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6204 Check_Component_List
6205 (Component_List (Type_Definition (Decl)),
6207 Discriminant_Specifications (Decl));
6210 end Record_Hole_Check;
6213 -- For records that have component clauses for all components, and whose
6214 -- size is less than or equal to 32, we need to know the size in the
6215 -- front end to activate possible packed array processing where the
6216 -- component type is a record.
6218 -- At this stage Hbit + 1 represents the first unused bit from all the
6219 -- component clauses processed, so if the component clauses are
6220 -- complete, then this is the length of the record.
6222 -- For records longer than System.Storage_Unit, and for those where not
6223 -- all components have component clauses, the back end determines the
6224 -- length (it may for example be appropriate to round up the size
6225 -- to some convenient boundary, based on alignment considerations, etc).
6227 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
6229 -- Nothing to do if at least one component has no component clause
6231 Comp := First_Component_Or_Discriminant (Rectype);
6232 while Present (Comp) loop
6233 exit when No (Component_Clause (Comp));
6234 Next_Component_Or_Discriminant (Comp);
6237 -- If we fall out of loop, all components have component clauses
6238 -- and so we can set the size to the maximum value.
6241 Set_RM_Size (Rectype, Hbit + 1);
6244 end Check_Record_Representation_Clause;
6250 procedure Check_Size
6254 Biased : out Boolean)
6256 UT : constant Entity_Id := Underlying_Type (T);
6262 -- Dismiss cases for generic types or types with previous errors
6265 or else UT = Any_Type
6266 or else Is_Generic_Type (UT)
6267 or else Is_Generic_Type (Root_Type (UT))
6271 -- Check case of bit packed array
6273 elsif Is_Array_Type (UT)
6274 and then Known_Static_Component_Size (UT)
6275 and then Is_Bit_Packed_Array (UT)
6283 Asiz := Component_Size (UT);
6284 Indx := First_Index (UT);
6286 Ityp := Etype (Indx);
6288 -- If non-static bound, then we are not in the business of
6289 -- trying to check the length, and indeed an error will be
6290 -- issued elsewhere, since sizes of non-static array types
6291 -- cannot be set implicitly or explicitly.
6293 if not Is_Static_Subtype (Ityp) then
6297 -- Otherwise accumulate next dimension
6299 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
6300 Expr_Value (Type_Low_Bound (Ityp)) +
6304 exit when No (Indx);
6310 Error_Msg_Uint_1 := Asiz;
6312 ("size for& too small, minimum allowed is ^", N, T);
6313 Set_Esize (T, Asiz);
6314 Set_RM_Size (T, Asiz);
6318 -- All other composite types are ignored
6320 elsif Is_Composite_Type (UT) then
6323 -- For fixed-point types, don't check minimum if type is not frozen,
6324 -- since we don't know all the characteristics of the type that can
6325 -- affect the size (e.g. a specified small) till freeze time.
6327 elsif Is_Fixed_Point_Type (UT)
6328 and then not Is_Frozen (UT)
6332 -- Cases for which a minimum check is required
6335 -- Ignore if specified size is correct for the type
6337 if Known_Esize (UT) and then Siz = Esize (UT) then
6341 -- Otherwise get minimum size
6343 M := UI_From_Int (Minimum_Size (UT));
6347 -- Size is less than minimum size, but one possibility remains
6348 -- that we can manage with the new size if we bias the type.
6350 M := UI_From_Int (Minimum_Size (UT, Biased => True));
6353 Error_Msg_Uint_1 := M;
6355 ("size for& too small, minimum allowed is ^", N, T);
6365 -------------------------
6366 -- Get_Alignment_Value --
6367 -------------------------
6369 function Get_Alignment_Value (Expr : Node_Id) return Uint is
6370 Align : constant Uint := Static_Integer (Expr);
6373 if Align = No_Uint then
6376 elsif Align <= 0 then
6377 Error_Msg_N ("alignment value must be positive", Expr);
6381 for J in Int range 0 .. 64 loop
6383 M : constant Uint := Uint_2 ** J;
6386 exit when M = Align;
6390 ("alignment value must be power of 2", Expr);
6398 end Get_Alignment_Value;
6404 procedure Initialize is
6406 Address_Clause_Checks.Init;
6407 Independence_Checks.Init;
6408 Unchecked_Conversions.Init;
6411 -------------------------
6412 -- Is_Operational_Item --
6413 -------------------------
6415 function Is_Operational_Item (N : Node_Id) return Boolean is
6417 if Nkind (N) /= N_Attribute_Definition_Clause then
6421 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
6423 return Id = Attribute_Input
6424 or else Id = Attribute_Output
6425 or else Id = Attribute_Read
6426 or else Id = Attribute_Write
6427 or else Id = Attribute_External_Tag;
6430 end Is_Operational_Item;
6436 function Minimum_Size
6438 Biased : Boolean := False) return Nat
6440 Lo : Uint := No_Uint;
6441 Hi : Uint := No_Uint;
6442 LoR : Ureal := No_Ureal;
6443 HiR : Ureal := No_Ureal;
6444 LoSet : Boolean := False;
6445 HiSet : Boolean := False;
6449 R_Typ : constant Entity_Id := Root_Type (T);
6452 -- If bad type, return 0
6454 if T = Any_Type then
6457 -- For generic types, just return zero. There cannot be any legitimate
6458 -- need to know such a size, but this routine may be called with a
6459 -- generic type as part of normal processing.
6461 elsif Is_Generic_Type (R_Typ)
6462 or else R_Typ = Any_Type
6466 -- Access types. Normally an access type cannot have a size smaller
6467 -- than the size of System.Address. The exception is on VMS, where
6468 -- we have short and long addresses, and it is possible for an access
6469 -- type to have a short address size (and thus be less than the size
6470 -- of System.Address itself). We simply skip the check for VMS, and
6471 -- leave it to the back end to do the check.
6473 elsif Is_Access_Type (T) then
6474 if OpenVMS_On_Target then
6477 return System_Address_Size;
6480 -- Floating-point types
6482 elsif Is_Floating_Point_Type (T) then
6483 return UI_To_Int (Esize (R_Typ));
6487 elsif Is_Discrete_Type (T) then
6489 -- The following loop is looking for the nearest compile time known
6490 -- bounds following the ancestor subtype chain. The idea is to find
6491 -- the most restrictive known bounds information.
6495 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6500 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
6501 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
6508 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
6509 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
6515 Ancest := Ancestor_Subtype (Ancest);
6518 Ancest := Base_Type (T);
6520 if Is_Generic_Type (Ancest) then
6526 -- Fixed-point types. We can't simply use Expr_Value to get the
6527 -- Corresponding_Integer_Value values of the bounds, since these do not
6528 -- get set till the type is frozen, and this routine can be called
6529 -- before the type is frozen. Similarly the test for bounds being static
6530 -- needs to include the case where we have unanalyzed real literals for
6533 elsif Is_Fixed_Point_Type (T) then
6535 -- The following loop is looking for the nearest compile time known
6536 -- bounds following the ancestor subtype chain. The idea is to find
6537 -- the most restrictive known bounds information.
6541 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
6545 -- Note: In the following two tests for LoSet and HiSet, it may
6546 -- seem redundant to test for N_Real_Literal here since normally
6547 -- one would assume that the test for the value being known at
6548 -- compile time includes this case. However, there is a glitch.
6549 -- If the real literal comes from folding a non-static expression,
6550 -- then we don't consider any non- static expression to be known
6551 -- at compile time if we are in configurable run time mode (needed
6552 -- in some cases to give a clearer definition of what is and what
6553 -- is not accepted). So the test is indeed needed. Without it, we
6554 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
6557 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
6558 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
6560 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
6567 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
6568 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
6570 HiR := Expr_Value_R (Type_High_Bound (Ancest));
6576 Ancest := Ancestor_Subtype (Ancest);
6579 Ancest := Base_Type (T);
6581 if Is_Generic_Type (Ancest) then
6587 Lo := UR_To_Uint (LoR / Small_Value (T));
6588 Hi := UR_To_Uint (HiR / Small_Value (T));
6590 -- No other types allowed
6593 raise Program_Error;
6596 -- Fall through with Hi and Lo set. Deal with biased case
6599 and then not Is_Fixed_Point_Type (T)
6600 and then not (Is_Enumeration_Type (T)
6601 and then Has_Non_Standard_Rep (T)))
6602 or else Has_Biased_Representation (T)
6608 -- Signed case. Note that we consider types like range 1 .. -1 to be
6609 -- signed for the purpose of computing the size, since the bounds have
6610 -- to be accommodated in the base type.
6612 if Lo < 0 or else Hi < 0 then
6616 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
6617 -- Note that we accommodate the case where the bounds cross. This
6618 -- can happen either because of the way the bounds are declared
6619 -- or because of the algorithm in Freeze_Fixed_Point_Type.
6633 -- If both bounds are positive, make sure that both are represen-
6634 -- table in the case where the bounds are crossed. This can happen
6635 -- either because of the way the bounds are declared, or because of
6636 -- the algorithm in Freeze_Fixed_Point_Type.
6642 -- S = size, (can accommodate 0 .. (2**size - 1))
6645 while Hi >= Uint_2 ** S loop
6653 ---------------------------
6654 -- New_Stream_Subprogram --
6655 ---------------------------
6657 procedure New_Stream_Subprogram
6661 Nam : TSS_Name_Type)
6663 Loc : constant Source_Ptr := Sloc (N);
6664 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
6665 Subp_Id : Entity_Id;
6666 Subp_Decl : Node_Id;
6670 Defer_Declaration : constant Boolean :=
6671 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
6672 -- For a tagged type, there is a declaration for each stream attribute
6673 -- at the freeze point, and we must generate only a completion of this
6674 -- declaration. We do the same for private types, because the full view
6675 -- might be tagged. Otherwise we generate a declaration at the point of
6676 -- the attribute definition clause.
6678 function Build_Spec return Node_Id;
6679 -- Used for declaration and renaming declaration, so that this is
6680 -- treated as a renaming_as_body.
6686 function Build_Spec return Node_Id is
6687 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
6690 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
6693 Subp_Id := Make_Defining_Identifier (Loc, Sname);
6695 -- S : access Root_Stream_Type'Class
6697 Formals := New_List (
6698 Make_Parameter_Specification (Loc,
6699 Defining_Identifier =>
6700 Make_Defining_Identifier (Loc, Name_S),
6702 Make_Access_Definition (Loc,
6705 Designated_Type (Etype (F)), Loc))));
6707 if Nam = TSS_Stream_Input then
6708 Spec := Make_Function_Specification (Loc,
6709 Defining_Unit_Name => Subp_Id,
6710 Parameter_Specifications => Formals,
6711 Result_Definition => T_Ref);
6716 Make_Parameter_Specification (Loc,
6717 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
6718 Out_Present => Out_P,
6719 Parameter_Type => T_Ref));
6722 Make_Procedure_Specification (Loc,
6723 Defining_Unit_Name => Subp_Id,
6724 Parameter_Specifications => Formals);
6730 -- Start of processing for New_Stream_Subprogram
6733 F := First_Formal (Subp);
6735 if Ekind (Subp) = E_Procedure then
6736 Etyp := Etype (Next_Formal (F));
6738 Etyp := Etype (Subp);
6741 -- Prepare subprogram declaration and insert it as an action on the
6742 -- clause node. The visibility for this entity is used to test for
6743 -- visibility of the attribute definition clause (in the sense of
6744 -- 8.3(23) as amended by AI-195).
6746 if not Defer_Declaration then
6748 Make_Subprogram_Declaration (Loc,
6749 Specification => Build_Spec);
6751 -- For a tagged type, there is always a visible declaration for each
6752 -- stream TSS (it is a predefined primitive operation), and the
6753 -- completion of this declaration occurs at the freeze point, which is
6754 -- not always visible at places where the attribute definition clause is
6755 -- visible. So, we create a dummy entity here for the purpose of
6756 -- tracking the visibility of the attribute definition clause itself.
6760 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
6762 Make_Object_Declaration (Loc,
6763 Defining_Identifier => Subp_Id,
6764 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
6767 Insert_Action (N, Subp_Decl);
6768 Set_Entity (N, Subp_Id);
6771 Make_Subprogram_Renaming_Declaration (Loc,
6772 Specification => Build_Spec,
6773 Name => New_Reference_To (Subp, Loc));
6775 if Defer_Declaration then
6776 Set_TSS (Base_Type (Ent), Subp_Id);
6778 Insert_Action (N, Subp_Decl);
6779 Copy_TSS (Subp_Id, Base_Type (Ent));
6781 end New_Stream_Subprogram;
6783 ------------------------
6784 -- Rep_Item_Too_Early --
6785 ------------------------
6787 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
6789 -- Cannot apply non-operational rep items to generic types
6791 if Is_Operational_Item (N) then
6795 and then Is_Generic_Type (Root_Type (T))
6797 Error_Msg_N ("representation item not allowed for generic type", N);
6801 -- Otherwise check for incomplete type
6803 if Is_Incomplete_Or_Private_Type (T)
6804 and then No (Underlying_Type (T))
6807 ("representation item must be after full type declaration", N);
6810 -- If the type has incomplete components, a representation clause is
6811 -- illegal but stream attributes and Convention pragmas are correct.
6813 elsif Has_Private_Component (T) then
6814 if Nkind (N) = N_Pragma then
6818 ("representation item must appear after type is fully defined",
6825 end Rep_Item_Too_Early;
6827 -----------------------
6828 -- Rep_Item_Too_Late --
6829 -----------------------
6831 function Rep_Item_Too_Late
6834 FOnly : Boolean := False) return Boolean
6837 Parent_Type : Entity_Id;
6840 -- Output the too late message. Note that this is not considered a
6841 -- serious error, since the effect is simply that we ignore the
6842 -- representation clause in this case.
6848 procedure Too_Late is
6850 Error_Msg_N ("|representation item appears too late!", N);
6853 -- Start of processing for Rep_Item_Too_Late
6856 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
6857 -- types, which may be frozen if they appear in a representation clause
6858 -- for a local type.
6861 and then not From_With_Type (T)
6864 S := First_Subtype (T);
6866 if Present (Freeze_Node (S)) then
6868 ("?no more representation items for }", Freeze_Node (S), S);
6873 -- Check for case of non-tagged derived type whose parent either has
6874 -- primitive operations, or is a by reference type (RM 13.1(10)).
6878 and then Is_Derived_Type (T)
6879 and then not Is_Tagged_Type (T)
6881 Parent_Type := Etype (Base_Type (T));
6883 if Has_Primitive_Operations (Parent_Type) then
6886 ("primitive operations already defined for&!", N, Parent_Type);
6889 elsif Is_By_Reference_Type (Parent_Type) then
6892 ("parent type & is a by reference type!", N, Parent_Type);
6897 -- No error, link item into head of chain of rep items for the entity,
6898 -- but avoid chaining if we have an overloadable entity, and the pragma
6899 -- is one that can apply to multiple overloaded entities.
6901 if Is_Overloadable (T)
6902 and then Nkind (N) = N_Pragma
6905 Pname : constant Name_Id := Pragma_Name (N);
6907 if Pname = Name_Convention or else
6908 Pname = Name_Import or else
6909 Pname = Name_Export or else
6910 Pname = Name_External or else
6911 Pname = Name_Interface
6918 Record_Rep_Item (T, N);
6920 end Rep_Item_Too_Late;
6922 -------------------------------------
6923 -- Replace_Type_References_Generic --
6924 -------------------------------------
6926 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
6928 function Replace_Node (N : Node_Id) return Traverse_Result;
6929 -- Processes a single node in the traversal procedure below, checking
6930 -- if node N should be replaced, and if so, doing the replacement.
6932 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
6933 -- This instantiation provides the body of Replace_Type_References
6939 function Replace_Node (N : Node_Id) return Traverse_Result is
6944 -- Case of identifier
6946 if Nkind (N) = N_Identifier then
6948 -- If not the type name, all done with this node
6950 if Chars (N) /= TName then
6953 -- Otherwise do the replacement and we are done with this node
6956 Replace_Type_Reference (N);
6960 -- Case of selected component (which is what a qualification
6961 -- looks like in the unanalyzed tree, which is what we have.
6963 elsif Nkind (N) = N_Selected_Component then
6965 -- If selector name is not our type, keeping going (we might
6966 -- still have an occurrence of the type in the prefix).
6968 if Nkind (Selector_Name (N)) /= N_Identifier
6969 or else Chars (Selector_Name (N)) /= TName
6973 -- Selector name is our type, check qualification
6976 -- Loop through scopes and prefixes, doing comparison
6981 -- Continue if no more scopes or scope with no name
6983 if No (S) or else Nkind (S) not in N_Has_Chars then
6987 -- Do replace if prefix is an identifier matching the
6988 -- scope that we are currently looking at.
6990 if Nkind (P) = N_Identifier
6991 and then Chars (P) = Chars (S)
6993 Replace_Type_Reference (N);
6997 -- Go check scope above us if prefix is itself of the
6998 -- form of a selected component, whose selector matches
6999 -- the scope we are currently looking at.
7001 if Nkind (P) = N_Selected_Component
7002 and then Nkind (Selector_Name (P)) = N_Identifier
7003 and then Chars (Selector_Name (P)) = Chars (S)
7008 -- For anything else, we don't have a match, so keep on
7009 -- going, there are still some weird cases where we may
7010 -- still have a replacement within the prefix.
7018 -- Continue for any other node kind
7026 Replace_Type_Refs (N);
7027 end Replace_Type_References_Generic;
7029 -------------------------
7030 -- Same_Representation --
7031 -------------------------
7033 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7034 T1 : constant Entity_Id := Underlying_Type (Typ1);
7035 T2 : constant Entity_Id := Underlying_Type (Typ2);
7038 -- A quick check, if base types are the same, then we definitely have
7039 -- the same representation, because the subtype specific representation
7040 -- attributes (Size and Alignment) do not affect representation from
7041 -- the point of view of this test.
7043 if Base_Type (T1) = Base_Type (T2) then
7046 elsif Is_Private_Type (Base_Type (T2))
7047 and then Base_Type (T1) = Full_View (Base_Type (T2))
7052 -- Tagged types never have differing representations
7054 if Is_Tagged_Type (T1) then
7058 -- Representations are definitely different if conventions differ
7060 if Convention (T1) /= Convention (T2) then
7064 -- Representations are different if component alignments differ
7066 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7068 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7069 and then Component_Alignment (T1) /= Component_Alignment (T2)
7074 -- For arrays, the only real issue is component size. If we know the
7075 -- component size for both arrays, and it is the same, then that's
7076 -- good enough to know we don't have a change of representation.
7078 if Is_Array_Type (T1) then
7079 if Known_Component_Size (T1)
7080 and then Known_Component_Size (T2)
7081 and then Component_Size (T1) = Component_Size (T2)
7087 -- Types definitely have same representation if neither has non-standard
7088 -- representation since default representations are always consistent.
7089 -- If only one has non-standard representation, and the other does not,
7090 -- then we consider that they do not have the same representation. They
7091 -- might, but there is no way of telling early enough.
7093 if Has_Non_Standard_Rep (T1) then
7094 if not Has_Non_Standard_Rep (T2) then
7098 return not Has_Non_Standard_Rep (T2);
7101 -- Here the two types both have non-standard representation, and we need
7102 -- to determine if they have the same non-standard representation.
7104 -- For arrays, we simply need to test if the component sizes are the
7105 -- same. Pragma Pack is reflected in modified component sizes, so this
7106 -- check also deals with pragma Pack.
7108 if Is_Array_Type (T1) then
7109 return Component_Size (T1) = Component_Size (T2);
7111 -- Tagged types always have the same representation, because it is not
7112 -- possible to specify different representations for common fields.
7114 elsif Is_Tagged_Type (T1) then
7117 -- Case of record types
7119 elsif Is_Record_Type (T1) then
7121 -- Packed status must conform
7123 if Is_Packed (T1) /= Is_Packed (T2) then
7126 -- Otherwise we must check components. Typ2 maybe a constrained
7127 -- subtype with fewer components, so we compare the components
7128 -- of the base types.
7131 Record_Case : declare
7132 CD1, CD2 : Entity_Id;
7134 function Same_Rep return Boolean;
7135 -- CD1 and CD2 are either components or discriminants. This
7136 -- function tests whether the two have the same representation
7142 function Same_Rep return Boolean is
7144 if No (Component_Clause (CD1)) then
7145 return No (Component_Clause (CD2));
7149 Present (Component_Clause (CD2))
7151 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7153 Esize (CD1) = Esize (CD2);
7157 -- Start of processing for Record_Case
7160 if Has_Discriminants (T1) then
7161 CD1 := First_Discriminant (T1);
7162 CD2 := First_Discriminant (T2);
7164 -- The number of discriminants may be different if the
7165 -- derived type has fewer (constrained by values). The
7166 -- invisible discriminants retain the representation of
7167 -- the original, so the discrepancy does not per se
7168 -- indicate a different representation.
7171 and then Present (CD2)
7173 if not Same_Rep then
7176 Next_Discriminant (CD1);
7177 Next_Discriminant (CD2);
7182 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
7183 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
7185 while Present (CD1) loop
7186 if not Same_Rep then
7189 Next_Component (CD1);
7190 Next_Component (CD2);
7198 -- For enumeration types, we must check each literal to see if the
7199 -- representation is the same. Note that we do not permit enumeration
7200 -- representation clauses for Character and Wide_Character, so these
7201 -- cases were already dealt with.
7203 elsif Is_Enumeration_Type (T1) then
7204 Enumeration_Case : declare
7208 L1 := First_Literal (T1);
7209 L2 := First_Literal (T2);
7211 while Present (L1) loop
7212 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
7222 end Enumeration_Case;
7224 -- Any other types have the same representation for these purposes
7229 end Same_Representation;
7235 procedure Set_Biased
7239 Biased : Boolean := True)
7243 Set_Has_Biased_Representation (E);
7245 if Warn_On_Biased_Representation then
7247 ("?" & Msg & " forces biased representation for&", N, E);
7252 --------------------
7253 -- Set_Enum_Esize --
7254 --------------------
7256 procedure Set_Enum_Esize (T : Entity_Id) is
7264 -- Find the minimum standard size (8,16,32,64) that fits
7266 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
7267 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
7270 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
7271 Sz := Standard_Character_Size; -- May be > 8 on some targets
7273 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
7276 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
7279 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
7284 if Hi < Uint_2**08 then
7285 Sz := Standard_Character_Size; -- May be > 8 on some targets
7287 elsif Hi < Uint_2**16 then
7290 elsif Hi < Uint_2**32 then
7293 else pragma Assert (Hi < Uint_2**63);
7298 -- That minimum is the proper size unless we have a foreign convention
7299 -- and the size required is 32 or less, in which case we bump the size
7300 -- up to 32. This is required for C and C++ and seems reasonable for
7301 -- all other foreign conventions.
7303 if Has_Foreign_Convention (T)
7304 and then Esize (T) < Standard_Integer_Size
7306 Init_Esize (T, Standard_Integer_Size);
7312 ------------------------------
7313 -- Validate_Address_Clauses --
7314 ------------------------------
7316 procedure Validate_Address_Clauses is
7318 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
7320 ACCR : Address_Clause_Check_Record
7321 renames Address_Clause_Checks.Table (J);
7332 -- Skip processing of this entry if warning already posted
7334 if not Address_Warning_Posted (ACCR.N) then
7336 Expr := Original_Node (Expression (ACCR.N));
7340 X_Alignment := Alignment (ACCR.X);
7341 Y_Alignment := Alignment (ACCR.Y);
7343 -- Similarly obtain sizes
7345 X_Size := Esize (ACCR.X);
7346 Y_Size := Esize (ACCR.Y);
7348 -- Check for large object overlaying smaller one
7351 and then X_Size > Uint_0
7352 and then X_Size > Y_Size
7355 ("?& overlays smaller object", ACCR.N, ACCR.X);
7357 ("\?program execution may be erroneous", ACCR.N);
7358 Error_Msg_Uint_1 := X_Size;
7360 ("\?size of & is ^", ACCR.N, ACCR.X);
7361 Error_Msg_Uint_1 := Y_Size;
7363 ("\?size of & is ^", ACCR.N, ACCR.Y);
7365 -- Check for inadequate alignment, both of the base object
7366 -- and of the offset, if any.
7368 -- Note: we do not check the alignment if we gave a size
7369 -- warning, since it would likely be redundant.
7371 elsif Y_Alignment /= Uint_0
7372 and then (Y_Alignment < X_Alignment
7375 Nkind (Expr) = N_Attribute_Reference
7377 Attribute_Name (Expr) = Name_Address
7379 Has_Compatible_Alignment
7380 (ACCR.X, Prefix (Expr))
7381 /= Known_Compatible))
7384 ("?specified address for& may be inconsistent "
7388 ("\?program execution may be erroneous (RM 13.3(27))",
7390 Error_Msg_Uint_1 := X_Alignment;
7392 ("\?alignment of & is ^",
7394 Error_Msg_Uint_1 := Y_Alignment;
7396 ("\?alignment of & is ^",
7398 if Y_Alignment >= X_Alignment then
7400 ("\?but offset is not multiple of alignment",
7407 end Validate_Address_Clauses;
7409 ---------------------------
7410 -- Validate_Independence --
7411 ---------------------------
7413 procedure Validate_Independence is
7414 SU : constant Uint := UI_From_Int (System_Storage_Unit);
7422 procedure Check_Array_Type (Atyp : Entity_Id);
7423 -- Checks if the array type Atyp has independent components, and
7424 -- if not, outputs an appropriate set of error messages.
7426 procedure No_Independence;
7427 -- Output message that independence cannot be guaranteed
7429 function OK_Component (C : Entity_Id) return Boolean;
7430 -- Checks one component to see if it is independently accessible, and
7431 -- if so yields True, otherwise yields False if independent access
7432 -- cannot be guaranteed. This is a conservative routine, it only
7433 -- returns True if it knows for sure, it returns False if it knows
7434 -- there is a problem, or it cannot be sure there is no problem.
7436 procedure Reason_Bad_Component (C : Entity_Id);
7437 -- Outputs continuation message if a reason can be determined for
7438 -- the component C being bad.
7440 ----------------------
7441 -- Check_Array_Type --
7442 ----------------------
7444 procedure Check_Array_Type (Atyp : Entity_Id) is
7445 Ctyp : constant Entity_Id := Component_Type (Atyp);
7448 -- OK if no alignment clause, no pack, and no component size
7450 if not Has_Component_Size_Clause (Atyp)
7451 and then not Has_Alignment_Clause (Atyp)
7452 and then not Is_Packed (Atyp)
7457 -- Check actual component size
7459 if not Known_Component_Size (Atyp)
7460 or else not (Addressable (Component_Size (Atyp))
7461 and then Component_Size (Atyp) < 64)
7462 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
7466 -- Bad component size, check reason
7468 if Has_Component_Size_Clause (Atyp) then
7470 Get_Attribute_Definition_Clause
7471 (Atyp, Attribute_Component_Size);
7474 Error_Msg_Sloc := Sloc (P);
7475 Error_Msg_N ("\because of Component_Size clause#", N);
7480 if Is_Packed (Atyp) then
7481 P := Get_Rep_Pragma (Atyp, Name_Pack);
7484 Error_Msg_Sloc := Sloc (P);
7485 Error_Msg_N ("\because of pragma Pack#", N);
7490 -- No reason found, just return
7495 -- Array type is OK independence-wise
7498 end Check_Array_Type;
7500 ---------------------
7501 -- No_Independence --
7502 ---------------------
7504 procedure No_Independence is
7506 if Pragma_Name (N) = Name_Independent then
7508 ("independence cannot be guaranteed for&", N, E);
7511 ("independent components cannot be guaranteed for&", N, E);
7513 end No_Independence;
7519 function OK_Component (C : Entity_Id) return Boolean is
7520 Rec : constant Entity_Id := Scope (C);
7521 Ctyp : constant Entity_Id := Etype (C);
7524 -- OK if no component clause, no Pack, and no alignment clause
7526 if No (Component_Clause (C))
7527 and then not Is_Packed (Rec)
7528 and then not Has_Alignment_Clause (Rec)
7533 -- Here we look at the actual component layout. A component is
7534 -- addressable if its size is a multiple of the Esize of the
7535 -- component type, and its starting position in the record has
7536 -- appropriate alignment, and the record itself has appropriate
7537 -- alignment to guarantee the component alignment.
7539 -- Make sure sizes are static, always assume the worst for any
7540 -- cases where we cannot check static values.
7542 if not (Known_Static_Esize (C)
7543 and then Known_Static_Esize (Ctyp))
7548 -- Size of component must be addressable or greater than 64 bits
7549 -- and a multiple of bytes.
7551 if not Addressable (Esize (C))
7552 and then Esize (C) < Uint_64
7557 -- Check size is proper multiple
7559 if Esize (C) mod Esize (Ctyp) /= 0 then
7563 -- Check alignment of component is OK
7565 if not Known_Component_Bit_Offset (C)
7566 or else Component_Bit_Offset (C) < Uint_0
7567 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
7572 -- Check alignment of record type is OK
7574 if not Known_Alignment (Rec)
7575 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7580 -- All tests passed, component is addressable
7585 --------------------------
7586 -- Reason_Bad_Component --
7587 --------------------------
7589 procedure Reason_Bad_Component (C : Entity_Id) is
7590 Rec : constant Entity_Id := Scope (C);
7591 Ctyp : constant Entity_Id := Etype (C);
7594 -- If component clause present assume that's the problem
7596 if Present (Component_Clause (C)) then
7597 Error_Msg_Sloc := Sloc (Component_Clause (C));
7598 Error_Msg_N ("\because of Component_Clause#", N);
7602 -- If pragma Pack clause present, assume that's the problem
7604 if Is_Packed (Rec) then
7605 P := Get_Rep_Pragma (Rec, Name_Pack);
7608 Error_Msg_Sloc := Sloc (P);
7609 Error_Msg_N ("\because of pragma Pack#", N);
7614 -- See if record has bad alignment clause
7616 if Has_Alignment_Clause (Rec)
7617 and then Known_Alignment (Rec)
7618 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
7620 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
7623 Error_Msg_Sloc := Sloc (P);
7624 Error_Msg_N ("\because of Alignment clause#", N);
7628 -- Couldn't find a reason, so return without a message
7631 end Reason_Bad_Component;
7633 -- Start of processing for Validate_Independence
7636 for J in Independence_Checks.First .. Independence_Checks.Last loop
7637 N := Independence_Checks.Table (J).N;
7638 E := Independence_Checks.Table (J).E;
7639 IC := Pragma_Name (N) = Name_Independent_Components;
7641 -- Deal with component case
7643 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
7644 if not OK_Component (E) then
7646 Reason_Bad_Component (E);
7651 -- Deal with record with Independent_Components
7653 if IC and then Is_Record_Type (E) then
7654 Comp := First_Component_Or_Discriminant (E);
7655 while Present (Comp) loop
7656 if not OK_Component (Comp) then
7658 Reason_Bad_Component (Comp);
7662 Next_Component_Or_Discriminant (Comp);
7666 -- Deal with address clause case
7668 if Is_Object (E) then
7669 Addr := Address_Clause (E);
7671 if Present (Addr) then
7673 Error_Msg_Sloc := Sloc (Addr);
7674 Error_Msg_N ("\because of Address clause#", N);
7679 -- Deal with independent components for array type
7681 if IC and then Is_Array_Type (E) then
7682 Check_Array_Type (E);
7685 -- Deal with independent components for array object
7687 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
7688 Check_Array_Type (Etype (E));
7693 end Validate_Independence;
7695 -----------------------------------
7696 -- Validate_Unchecked_Conversion --
7697 -----------------------------------
7699 procedure Validate_Unchecked_Conversion
7701 Act_Unit : Entity_Id)
7708 -- Obtain source and target types. Note that we call Ancestor_Subtype
7709 -- here because the processing for generic instantiation always makes
7710 -- subtypes, and we want the original frozen actual types.
7712 -- If we are dealing with private types, then do the check on their
7713 -- fully declared counterparts if the full declarations have been
7714 -- encountered (they don't have to be visible, but they must exist!)
7716 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
7718 if Is_Private_Type (Source)
7719 and then Present (Underlying_Type (Source))
7721 Source := Underlying_Type (Source);
7724 Target := Ancestor_Subtype (Etype (Act_Unit));
7726 -- If either type is generic, the instantiation happens within a generic
7727 -- unit, and there is nothing to check. The proper check
7728 -- will happen when the enclosing generic is instantiated.
7730 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
7734 if Is_Private_Type (Target)
7735 and then Present (Underlying_Type (Target))
7737 Target := Underlying_Type (Target);
7740 -- Source may be unconstrained array, but not target
7742 if Is_Array_Type (Target)
7743 and then not Is_Constrained (Target)
7746 ("unchecked conversion to unconstrained array not allowed", N);
7750 -- Warn if conversion between two different convention pointers
7752 if Is_Access_Type (Target)
7753 and then Is_Access_Type (Source)
7754 and then Convention (Target) /= Convention (Source)
7755 and then Warn_On_Unchecked_Conversion
7757 -- Give warnings for subprogram pointers only on most targets. The
7758 -- exception is VMS, where data pointers can have different lengths
7759 -- depending on the pointer convention.
7761 if Is_Access_Subprogram_Type (Target)
7762 or else Is_Access_Subprogram_Type (Source)
7763 or else OpenVMS_On_Target
7766 ("?conversion between pointers with different conventions!", N);
7770 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
7771 -- warning when compiling GNAT-related sources.
7773 if Warn_On_Unchecked_Conversion
7774 and then not In_Predefined_Unit (N)
7775 and then RTU_Loaded (Ada_Calendar)
7777 (Chars (Source) = Name_Time
7779 Chars (Target) = Name_Time)
7781 -- If Ada.Calendar is loaded and the name of one of the operands is
7782 -- Time, there is a good chance that this is Ada.Calendar.Time.
7785 Calendar_Time : constant Entity_Id :=
7786 Full_View (RTE (RO_CA_Time));
7788 pragma Assert (Present (Calendar_Time));
7790 if Source = Calendar_Time
7791 or else Target = Calendar_Time
7794 ("?representation of 'Time values may change between " &
7795 "'G'N'A'T versions", N);
7800 -- Make entry in unchecked conversion table for later processing by
7801 -- Validate_Unchecked_Conversions, which will check sizes and alignments
7802 -- (using values set by the back-end where possible). This is only done
7803 -- if the appropriate warning is active.
7805 if Warn_On_Unchecked_Conversion then
7806 Unchecked_Conversions.Append
7807 (New_Val => UC_Entry'
7812 -- If both sizes are known statically now, then back end annotation
7813 -- is not required to do a proper check but if either size is not
7814 -- known statically, then we need the annotation.
7816 if Known_Static_RM_Size (Source)
7817 and then Known_Static_RM_Size (Target)
7821 Back_Annotate_Rep_Info := True;
7825 -- If unchecked conversion to access type, and access type is declared
7826 -- in the same unit as the unchecked conversion, then set the
7827 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
7830 if Is_Access_Type (Target) and then
7831 In_Same_Source_Unit (Target, N)
7833 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
7836 -- Generate N_Validate_Unchecked_Conversion node for back end in
7837 -- case the back end needs to perform special validation checks.
7839 -- Shouldn't this be in Exp_Ch13, since the check only gets done
7840 -- if we have full expansion and the back end is called ???
7843 Make_Validate_Unchecked_Conversion (Sloc (N));
7844 Set_Source_Type (Vnode, Source);
7845 Set_Target_Type (Vnode, Target);
7847 -- If the unchecked conversion node is in a list, just insert before it.
7848 -- If not we have some strange case, not worth bothering about.
7850 if Is_List_Member (N) then
7851 Insert_After (N, Vnode);
7853 end Validate_Unchecked_Conversion;
7855 ------------------------------------
7856 -- Validate_Unchecked_Conversions --
7857 ------------------------------------
7859 procedure Validate_Unchecked_Conversions is
7861 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
7863 T : UC_Entry renames Unchecked_Conversions.Table (N);
7865 Eloc : constant Source_Ptr := T.Eloc;
7866 Source : constant Entity_Id := T.Source;
7867 Target : constant Entity_Id := T.Target;
7873 -- This validation check, which warns if we have unequal sizes for
7874 -- unchecked conversion, and thus potentially implementation
7875 -- dependent semantics, is one of the few occasions on which we
7876 -- use the official RM size instead of Esize. See description in
7877 -- Einfo "Handling of Type'Size Values" for details.
7879 if Serious_Errors_Detected = 0
7880 and then Known_Static_RM_Size (Source)
7881 and then Known_Static_RM_Size (Target)
7883 -- Don't do the check if warnings off for either type, note the
7884 -- deliberate use of OR here instead of OR ELSE to get the flag
7885 -- Warnings_Off_Used set for both types if appropriate.
7887 and then not (Has_Warnings_Off (Source)
7889 Has_Warnings_Off (Target))
7891 Source_Siz := RM_Size (Source);
7892 Target_Siz := RM_Size (Target);
7894 if Source_Siz /= Target_Siz then
7896 ("?types for unchecked conversion have different sizes!",
7899 if All_Errors_Mode then
7900 Error_Msg_Name_1 := Chars (Source);
7901 Error_Msg_Uint_1 := Source_Siz;
7902 Error_Msg_Name_2 := Chars (Target);
7903 Error_Msg_Uint_2 := Target_Siz;
7904 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
7906 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
7908 if Is_Discrete_Type (Source)
7909 and then Is_Discrete_Type (Target)
7911 if Source_Siz > Target_Siz then
7913 ("\?^ high order bits of source will be ignored!",
7916 elsif Is_Unsigned_Type (Source) then
7918 ("\?source will be extended with ^ high order " &
7919 "zero bits?!", Eloc);
7923 ("\?source will be extended with ^ high order " &
7928 elsif Source_Siz < Target_Siz then
7929 if Is_Discrete_Type (Target) then
7930 if Bytes_Big_Endian then
7932 ("\?target value will include ^ undefined " &
7937 ("\?target value will include ^ undefined " &
7944 ("\?^ trailing bits of target value will be " &
7945 "undefined!", Eloc);
7948 else pragma Assert (Source_Siz > Target_Siz);
7950 ("\?^ trailing bits of source will be ignored!",
7957 -- If both types are access types, we need to check the alignment.
7958 -- If the alignment of both is specified, we can do it here.
7960 if Serious_Errors_Detected = 0
7961 and then Ekind (Source) in Access_Kind
7962 and then Ekind (Target) in Access_Kind
7963 and then Target_Strict_Alignment
7964 and then Present (Designated_Type (Source))
7965 and then Present (Designated_Type (Target))
7968 D_Source : constant Entity_Id := Designated_Type (Source);
7969 D_Target : constant Entity_Id := Designated_Type (Target);
7972 if Known_Alignment (D_Source)
7973 and then Known_Alignment (D_Target)
7976 Source_Align : constant Uint := Alignment (D_Source);
7977 Target_Align : constant Uint := Alignment (D_Target);
7980 if Source_Align < Target_Align
7981 and then not Is_Tagged_Type (D_Source)
7983 -- Suppress warning if warnings suppressed on either
7984 -- type or either designated type. Note the use of
7985 -- OR here instead of OR ELSE. That is intentional,
7986 -- we would like to set flag Warnings_Off_Used in
7987 -- all types for which warnings are suppressed.
7989 and then not (Has_Warnings_Off (D_Source)
7991 Has_Warnings_Off (D_Target)
7993 Has_Warnings_Off (Source)
7995 Has_Warnings_Off (Target))
7997 Error_Msg_Uint_1 := Target_Align;
7998 Error_Msg_Uint_2 := Source_Align;
7999 Error_Msg_Node_1 := D_Target;
8000 Error_Msg_Node_2 := D_Source;
8002 ("?alignment of & (^) is stricter than " &
8003 "alignment of & (^)!", Eloc);
8005 ("\?resulting access value may have invalid " &
8006 "alignment!", Eloc);
8014 end Validate_Unchecked_Conversions;
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