1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Disp; use Exp_Disp;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
43 with Rtsfind; use Rtsfind;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Ch3; use Sem_Ch3;
47 with Sem_Ch6; use Sem_Ch6;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Res; use Sem_Res;
51 with Sem_Type; use Sem_Type;
52 with Sem_Util; use Sem_Util;
53 with Sem_Warn; use Sem_Warn;
54 with Sinput; use Sinput;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Stringt; use Stringt;
59 with Targparm; use Targparm;
60 with Ttypes; use Ttypes;
61 with Tbuild; use Tbuild;
62 with Urealp; use Urealp;
63 with Warnsw; use Warnsw;
65 with GNAT.Heap_Sort_G;
67 package body Sem_Ch13 is
69 SSU : constant Pos := System_Storage_Unit;
70 -- Convenient short hand for commonly used constant
72 -----------------------
73 -- Local Subprograms --
74 -----------------------
76 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint);
77 -- This routine is called after setting one of the sizes of type entity
78 -- Typ to Size. The purpose is to deal with the situation of a derived
79 -- type whose inherited alignment is no longer appropriate for the new
80 -- size value. In this case, we reset the Alignment to unknown.
82 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
83 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
84 -- then either there are pragma Invariant entries on the rep chain for the
85 -- type (note that Predicate aspects are converted to pragma Predicate), or
86 -- there are inherited aspects from a parent type, or ancestor subtypes.
87 -- This procedure builds the spec and body for the Predicate function that
88 -- tests these predicates. N is the freeze node for the type. The spec of
89 -- the function is inserted before the freeze node, and the body of the
90 -- function is inserted after the freeze node.
92 procedure Build_Static_Predicate
96 -- Given a predicated type Typ, where Typ is a discrete static subtype,
97 -- whose predicate expression is Expr, tests if Expr is a static predicate,
98 -- and if so, builds the predicate range list. Nam is the name of the one
99 -- argument to the predicate function. Occurrences of the type name in the
100 -- predicate expression have been replaced by identifier references to this
101 -- name, which is unique, so any identifier with Chars matching Nam must be
102 -- a reference to the type. If the predicate is non-static, this procedure
103 -- returns doing nothing. If the predicate is static, then the predicate
104 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
105 -- a canonicalized membership operation.
107 function Get_Alignment_Value (Expr : Node_Id) return Uint;
108 -- Given the expression for an alignment value, returns the corresponding
109 -- Uint value. If the value is inappropriate, then error messages are
110 -- posted as required, and a value of No_Uint is returned.
112 function Is_Operational_Item (N : Node_Id) return Boolean;
113 -- A specification for a stream attribute is allowed before the full type
114 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
115 -- that do not specify a representation characteristic are operational
118 procedure New_Stream_Subprogram
122 Nam : TSS_Name_Type);
123 -- Create a subprogram renaming of a given stream attribute to the
124 -- designated subprogram and then in the tagged case, provide this as a
125 -- primitive operation, or in the non-tagged case make an appropriate TSS
126 -- entry. This is more properly an expansion activity than just semantics,
127 -- but the presence of user-defined stream functions for limited types is a
128 -- legality check, which is why this takes place here rather than in
129 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
130 -- function to be generated.
132 -- To avoid elaboration anomalies with freeze nodes, for untagged types
133 -- we generate both a subprogram declaration and a subprogram renaming
134 -- declaration, so that the attribute specification is handled as a
135 -- renaming_as_body. For tagged types, the specification is one of the
139 with procedure Replace_Type_Reference (N : Node_Id);
140 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
141 -- This is used to scan an expression for a predicate or invariant aspect
142 -- replacing occurrences of the name TName (the name of the subtype to
143 -- which the aspect applies) with appropriate references to the parameter
144 -- of the predicate function or invariant procedure. The procedure passed
145 -- as a generic parameter does the actual replacement of node N, which is
146 -- either a simple direct reference to TName, or a selected component that
147 -- represents an appropriately qualified occurrence of TName.
153 Biased : Boolean := True);
154 -- If Biased is True, sets Has_Biased_Representation flag for E, and
155 -- outputs a warning message at node N if Warn_On_Biased_Representation is
156 -- is True. This warning inserts the string Msg to describe the construct
159 ----------------------------------------------
160 -- Table for Validate_Unchecked_Conversions --
161 ----------------------------------------------
163 -- The following table collects unchecked conversions for validation.
164 -- Entries are made by Validate_Unchecked_Conversion and then the
165 -- call to Validate_Unchecked_Conversions does the actual error
166 -- checking and posting of warnings. The reason for this delayed
167 -- processing is to take advantage of back-annotations of size and
168 -- alignment values performed by the back end.
170 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
171 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
172 -- will already have modified all Sloc values if the -gnatD option is set.
174 type UC_Entry is record
175 Eloc : Source_Ptr; -- node used for posting warnings
176 Source : Entity_Id; -- source type for unchecked conversion
177 Target : Entity_Id; -- target type for unchecked conversion
180 package Unchecked_Conversions is new Table.Table (
181 Table_Component_Type => UC_Entry,
182 Table_Index_Type => Int,
183 Table_Low_Bound => 1,
185 Table_Increment => 200,
186 Table_Name => "Unchecked_Conversions");
188 ----------------------------------------
189 -- Table for Validate_Address_Clauses --
190 ----------------------------------------
192 -- If an address clause has the form
194 -- for X'Address use Expr
196 -- where Expr is of the form Y'Address or recursively is a reference
197 -- to a constant of either of these forms, and X and Y are entities of
198 -- objects, then if Y has a smaller alignment than X, that merits a
199 -- warning about possible bad alignment. The following table collects
200 -- address clauses of this kind. We put these in a table so that they
201 -- can be checked after the back end has completed annotation of the
202 -- alignments of objects, since we can catch more cases that way.
204 type Address_Clause_Check_Record is record
206 -- The address clause
209 -- The entity of the object overlaying Y
212 -- The entity of the object being overlaid
215 -- Whether the address is offset within Y
218 package Address_Clause_Checks is new Table.Table (
219 Table_Component_Type => Address_Clause_Check_Record,
220 Table_Index_Type => Int,
221 Table_Low_Bound => 1,
223 Table_Increment => 200,
224 Table_Name => "Address_Clause_Checks");
226 -----------------------------------------
227 -- Adjust_Record_For_Reverse_Bit_Order --
228 -----------------------------------------
230 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
235 -- Processing depends on version of Ada
237 -- For Ada 95, we just renumber bits within a storage unit. We do the
238 -- same for Ada 83 mode, since we recognize the Bit_Order attribute in
239 -- Ada 83, and are free to add this extension.
241 if Ada_Version < Ada_2005 then
242 Comp := First_Component_Or_Discriminant (R);
243 while Present (Comp) loop
244 CC := Component_Clause (Comp);
246 -- If component clause is present, then deal with the non-default
247 -- bit order case for Ada 95 mode.
249 -- We only do this processing for the base type, and in fact that
250 -- is important, since otherwise if there are record subtypes, we
251 -- could reverse the bits once for each subtype, which is wrong.
254 and then Ekind (R) = E_Record_Type
257 CFB : constant Uint := Component_Bit_Offset (Comp);
258 CSZ : constant Uint := Esize (Comp);
259 CLC : constant Node_Id := Component_Clause (Comp);
260 Pos : constant Node_Id := Position (CLC);
261 FB : constant Node_Id := First_Bit (CLC);
263 Storage_Unit_Offset : constant Uint :=
264 CFB / System_Storage_Unit;
266 Start_Bit : constant Uint :=
267 CFB mod System_Storage_Unit;
270 -- Cases where field goes over storage unit boundary
272 if Start_Bit + CSZ > System_Storage_Unit then
274 -- Allow multi-byte field but generate warning
276 if Start_Bit mod System_Storage_Unit = 0
277 and then CSZ mod System_Storage_Unit = 0
280 ("multi-byte field specified with non-standard"
281 & " Bit_Order?", CLC);
283 if Bytes_Big_Endian then
285 ("bytes are not reversed "
286 & "(component is big-endian)?", CLC);
289 ("bytes are not reversed "
290 & "(component is little-endian)?", CLC);
293 -- Do not allow non-contiguous field
297 ("attempt to specify non-contiguous field "
298 & "not permitted", CLC);
300 ("\caused by non-standard Bit_Order "
303 ("\consider possibility of using "
304 & "Ada 2005 mode here", CLC);
307 -- Case where field fits in one storage unit
310 -- Give warning if suspicious component clause
312 if Intval (FB) >= System_Storage_Unit
313 and then Warn_On_Reverse_Bit_Order
316 ("?Bit_Order clause does not affect " &
317 "byte ordering", Pos);
319 Intval (Pos) + Intval (FB) /
322 ("?position normalized to ^ before bit " &
323 "order interpreted", Pos);
326 -- Here is where we fix up the Component_Bit_Offset value
327 -- to account for the reverse bit order. Some examples of
328 -- what needs to be done are:
330 -- First_Bit .. Last_Bit Component_Bit_Offset
342 -- The rule is that the first bit is is obtained by
343 -- subtracting the old ending bit from storage_unit - 1.
345 Set_Component_Bit_Offset
347 (Storage_Unit_Offset * System_Storage_Unit) +
348 (System_Storage_Unit - 1) -
349 (Start_Bit + CSZ - 1));
351 Set_Normalized_First_Bit
353 Component_Bit_Offset (Comp) mod
354 System_Storage_Unit);
359 Next_Component_Or_Discriminant (Comp);
362 -- For Ada 2005, we do machine scalar processing, as fully described In
363 -- AI-133. This involves gathering all components which start at the
364 -- same byte offset and processing them together. Same approach is still
365 -- valid in later versions including Ada 2012.
369 Max_Machine_Scalar_Size : constant Uint :=
371 (Standard_Long_Long_Integer_Size);
372 -- We use this as the maximum machine scalar size
375 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
378 -- This first loop through components does two things. First it
379 -- deals with the case of components with component clauses whose
380 -- length is greater than the maximum machine scalar size (either
381 -- accepting them or rejecting as needed). Second, it counts the
382 -- number of components with component clauses whose length does
383 -- not exceed this maximum for later processing.
386 Comp := First_Component_Or_Discriminant (R);
387 while Present (Comp) loop
388 CC := Component_Clause (Comp);
392 Fbit : constant Uint :=
393 Static_Integer (First_Bit (CC));
394 Lbit : constant Uint :=
395 Static_Integer (Last_Bit (CC));
398 -- Case of component with last bit >= max machine scalar
400 if Lbit >= Max_Machine_Scalar_Size then
402 -- This is allowed only if first bit is zero, and
403 -- last bit + 1 is a multiple of storage unit size.
405 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
407 -- This is the case to give a warning if enabled
409 if Warn_On_Reverse_Bit_Order then
411 ("multi-byte field specified with "
412 & " non-standard Bit_Order?", CC);
414 if Bytes_Big_Endian then
416 ("\bytes are not reversed "
417 & "(component is big-endian)?", CC);
420 ("\bytes are not reversed "
421 & "(component is little-endian)?", CC);
425 -- Give error message for RM 13.4.1(10) violation
429 ("machine scalar rules not followed for&",
430 First_Bit (CC), Comp);
432 Error_Msg_Uint_1 := Lbit;
433 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
435 ("\last bit (^) exceeds maximum machine "
439 if (Lbit + 1) mod SSU /= 0 then
440 Error_Msg_Uint_1 := SSU;
442 ("\and is not a multiple of Storage_Unit (^) "
447 Error_Msg_Uint_1 := Fbit;
449 ("\and first bit (^) is non-zero "
455 -- OK case of machine scalar related component clause,
456 -- For now, just count them.
459 Num_CC := Num_CC + 1;
464 Next_Component_Or_Discriminant (Comp);
467 -- We need to sort the component clauses on the basis of the
468 -- Position values in the clause, so we can group clauses with
469 -- the same Position. together to determine the relevant machine
473 Comps : array (0 .. Num_CC) of Entity_Id;
474 -- Array to collect component and discriminant entities. The
475 -- data starts at index 1, the 0'th entry is for the sort
478 function CP_Lt (Op1, Op2 : Natural) return Boolean;
479 -- Compare routine for Sort
481 procedure CP_Move (From : Natural; To : Natural);
482 -- Move routine for Sort
484 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
488 -- Start and stop positions in the component list of the set of
489 -- components with the same starting position (that constitute
490 -- components in a single machine scalar).
493 -- Maximum last bit value of any component in this set
496 -- Corresponding machine scalar size
502 function CP_Lt (Op1, Op2 : Natural) return Boolean is
504 return Position (Component_Clause (Comps (Op1))) <
505 Position (Component_Clause (Comps (Op2)));
512 procedure CP_Move (From : Natural; To : Natural) is
514 Comps (To) := Comps (From);
517 -- Start of processing for Sort_CC
520 -- Collect the machine scalar relevant component clauses
523 Comp := First_Component_Or_Discriminant (R);
524 while Present (Comp) loop
526 CC : constant Node_Id := Component_Clause (Comp);
529 -- Collect only component clauses whose last bit is less
530 -- than machine scalar size. Any component clause whose
531 -- last bit exceeds this value does not take part in
532 -- machine scalar layout considerations. The test for
533 -- Error_Posted makes sure we exclude component clauses
534 -- for which we already posted an error.
537 and then not Error_Posted (Last_Bit (CC))
538 and then Static_Integer (Last_Bit (CC)) <
539 Max_Machine_Scalar_Size
541 Num_CC := Num_CC + 1;
542 Comps (Num_CC) := Comp;
546 Next_Component_Or_Discriminant (Comp);
549 -- Sort by ascending position number
551 Sorting.Sort (Num_CC);
553 -- We now have all the components whose size does not exceed
554 -- the max machine scalar value, sorted by starting position.
555 -- In this loop we gather groups of clauses starting at the
556 -- same position, to process them in accordance with AI-133.
559 while Stop < Num_CC loop
564 (Last_Bit (Component_Clause (Comps (Start))));
565 while Stop < Num_CC loop
567 (Position (Component_Clause (Comps (Stop + 1)))) =
569 (Position (Component_Clause (Comps (Stop))))
577 (Component_Clause (Comps (Stop)))));
583 -- Now we have a group of component clauses from Start to
584 -- Stop whose positions are identical, and MaxL is the
585 -- maximum last bit value of any of these components.
587 -- We need to determine the corresponding machine scalar
588 -- size. This loop assumes that machine scalar sizes are
589 -- even, and that each possible machine scalar has twice
590 -- as many bits as the next smaller one.
592 MSS := Max_Machine_Scalar_Size;
594 and then (MSS / 2) >= SSU
595 and then (MSS / 2) > MaxL
600 -- Here is where we fix up the Component_Bit_Offset value
601 -- to account for the reverse bit order. Some examples of
602 -- what needs to be done for the case of a machine scalar
605 -- First_Bit .. Last_Bit Component_Bit_Offset
617 -- The rule is that the first bit is obtained by subtracting
618 -- the old ending bit from machine scalar size - 1.
620 for C in Start .. Stop loop
622 Comp : constant Entity_Id := Comps (C);
623 CC : constant Node_Id :=
624 Component_Clause (Comp);
625 LB : constant Uint :=
626 Static_Integer (Last_Bit (CC));
627 NFB : constant Uint := MSS - Uint_1 - LB;
628 NLB : constant Uint := NFB + Esize (Comp) - 1;
629 Pos : constant Uint :=
630 Static_Integer (Position (CC));
633 if Warn_On_Reverse_Bit_Order then
634 Error_Msg_Uint_1 := MSS;
636 ("info: reverse bit order in machine " &
637 "scalar of length^?", First_Bit (CC));
638 Error_Msg_Uint_1 := NFB;
639 Error_Msg_Uint_2 := NLB;
641 if Bytes_Big_Endian then
643 ("?\info: big-endian range for "
644 & "component & is ^ .. ^",
645 First_Bit (CC), Comp);
648 ("?\info: little-endian range "
649 & "for component & is ^ .. ^",
650 First_Bit (CC), Comp);
654 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
655 Set_Normalized_First_Bit (Comp, NFB mod SSU);
662 end Adjust_Record_For_Reverse_Bit_Order;
664 -------------------------------------
665 -- Alignment_Check_For_Size_Change --
666 -------------------------------------
668 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint) is
670 -- If the alignment is known, and not set by a rep clause, and is
671 -- inconsistent with the size being set, then reset it to unknown,
672 -- we assume in this case that the size overrides the inherited
673 -- alignment, and that the alignment must be recomputed.
675 if Known_Alignment (Typ)
676 and then not Has_Alignment_Clause (Typ)
677 and then Size mod (Alignment (Typ) * SSU) /= 0
679 Init_Alignment (Typ);
681 end Alignment_Check_For_Size_Change;
683 -----------------------------------
684 -- Analyze_Aspect_Specifications --
685 -----------------------------------
687 procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is
692 L : constant List_Id := Aspect_Specifications (N);
694 Ins_Node : Node_Id := N;
695 -- Insert pragmas (except Pre/Post/Invariant/Predicate) after this node
697 -- The general processing involves building an attribute definition
698 -- clause or a pragma node that corresponds to the aspect. Then one
699 -- of two things happens:
701 -- If we are required to delay the evaluation of this aspect to the
702 -- freeze point, we attach the corresponding pragma/attribute definition
703 -- clause to the aspect specification node, which is then placed in the
704 -- Rep Item chain. In this case we mark the entity by setting the flag
705 -- Has_Delayed_Aspects and we evaluate the rep item at the freeze point.
707 -- If no delay is required, we just insert the pragma or attribute
708 -- after the declaration, and it will get processed by the normal
709 -- circuit. The From_Aspect_Specification flag is set on the pragma
710 -- or attribute definition node in either case to activate special
711 -- processing (e.g. not traversing the list of homonyms for inline).
713 Delay_Required : Boolean;
714 -- Set True if delay is required
717 pragma Assert (Present (L));
719 -- Loop through aspects
722 Aspect_Loop : while Present (Aspect) loop
724 Loc : constant Source_Ptr := Sloc (Aspect);
725 Id : constant Node_Id := Identifier (Aspect);
726 Expr : constant Node_Id := Expression (Aspect);
727 Nam : constant Name_Id := Chars (Id);
728 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
731 Eloc : Source_Ptr := Sloc (Expr);
732 -- Source location of expression, modified when we split PPC's
734 procedure Check_False_Aspect_For_Derived_Type;
735 -- This procedure checks for the case of a false aspect for a
736 -- derived type, which improperly tries to cancel an aspect
737 -- inherited from the parent;
739 -----------------------------------------
740 -- Check_False_Aspect_For_Derived_Type --
741 -----------------------------------------
743 procedure Check_False_Aspect_For_Derived_Type is
745 -- We are only checking derived types
747 if not Is_Derived_Type (E) then
752 when Aspect_Atomic | Aspect_Shared =>
753 if not Is_Atomic (E) then
757 when Aspect_Atomic_Components =>
758 if not Has_Atomic_Components (E) then
762 when Aspect_Discard_Names =>
763 if not Discard_Names (E) then
768 if not Is_Packed (E) then
772 when Aspect_Unchecked_Union =>
773 if not Is_Unchecked_Union (E) then
777 when Aspect_Volatile =>
778 if not Is_Volatile (E) then
782 when Aspect_Volatile_Components =>
783 if not Has_Volatile_Components (E) then
791 -- Fall through means we are canceling an inherited aspect
793 Error_Msg_Name_1 := Nam;
795 ("derived type& inherits aspect%, cannot cancel", Expr, E);
796 end Check_False_Aspect_For_Derived_Type;
798 -- Start of processing for Aspect_Loop
801 -- Skip aspect if already analyzed (not clear if this is needed)
803 if Analyzed (Aspect) then
807 Set_Analyzed (Aspect);
808 Set_Entity (Aspect, E);
809 Ent := New_Occurrence_Of (E, Sloc (Id));
811 -- Check for duplicate aspect. Note that the Comes_From_Source
812 -- test allows duplicate Pre/Post's that we generate internally
813 -- to escape being flagged here.
815 if No_Duplicates_Allowed (A_Id) then
817 while Anod /= Aspect loop
819 (A_Id, Get_Aspect_Id (Chars (Identifier (Anod))))
820 and then Comes_From_Source (Aspect)
822 Error_Msg_Name_1 := Nam;
823 Error_Msg_Sloc := Sloc (Anod);
825 -- Case of same aspect specified twice
827 if Class_Present (Anod) = Class_Present (Aspect) then
828 if not Class_Present (Anod) then
830 ("aspect% for & previously given#",
834 ("aspect `%''Class` for & previously given#",
838 -- Case of Pre and Pre'Class both specified
840 elsif Nam = Name_Pre then
841 if Class_Present (Aspect) then
843 ("aspect `Pre''Class` for & is not allowed here",
846 ("\since aspect `Pre` previously given#",
851 ("aspect `Pre` for & is not allowed here",
854 ("\since aspect `Pre''Class` previously given#",
859 -- Allowed case of X and X'Class both specified
866 -- Copy expression for later processing by the procedures
867 -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations]
869 Set_Entity (Id, New_Copy_Tree (Expr));
871 -- Processing based on specific aspect
875 -- No_Aspect should be impossible
880 -- Aspects taking an optional boolean argument. For all of
881 -- these we just create a matching pragma and insert it, if
882 -- the expression is missing or set to True. If the expression
883 -- is False, we can ignore the aspect with the exception that
884 -- in the case of a derived type, we must check for an illegal
885 -- attempt to cancel an inherited aspect.
887 when Boolean_Aspects =>
888 Set_Is_Boolean_Aspect (Aspect);
891 and then Is_False (Static_Boolean (Expr))
893 Check_False_Aspect_For_Derived_Type;
897 -- If True, build corresponding pragma node
901 Pragma_Argument_Associations => New_List (Ent),
903 Make_Identifier (Sloc (Id), Chars (Id)));
905 -- Never need to delay for boolean aspects
907 Delay_Required := False;
909 -- Library unit aspects. These are boolean aspects, but we
910 -- have to do special things with the insertion, since the
911 -- pragma belongs inside the declarations of a package.
913 when Library_Unit_Aspects =>
915 and then Is_False (Static_Boolean (Expr))
920 -- Build corresponding pragma node
924 Pragma_Argument_Associations => New_List (Ent),
926 Make_Identifier (Sloc (Id), Chars (Id)));
928 -- This requires special handling in the case of a package
929 -- declaration, the pragma needs to be inserted in the list
930 -- of declarations for the associated package. There is no
931 -- issue of visibility delay for these aspects.
933 if Nkind (N) = N_Package_Declaration then
934 if Nkind (Parent (N)) /= N_Compilation_Unit then
936 ("incorrect context for library unit aspect&", Id);
939 (Aitem, Visible_Declarations (Specification (N)));
945 -- If not package declaration, no delay is required
947 Delay_Required := False;
949 -- Aspects related to container iterators. These aspects denote
950 -- subprograms, and thus must be delayed.
952 when Aspect_Constant_Indexing |
953 Aspect_Variable_Indexing =>
955 if not Is_Type (E) or else not Is_Tagged_Type (E) then
956 Error_Msg_N ("indexing applies to a tagged type", N);
960 Make_Attribute_Definition_Clause (Loc,
963 Expression => Relocate_Node (Expr));
965 Delay_Required := True;
966 Set_Is_Delayed_Aspect (Aspect);
968 when Aspect_Default_Iterator |
969 Aspect_Iterator_Element =>
972 Make_Attribute_Definition_Clause (Loc,
975 Expression => Relocate_Node (Expr));
977 Delay_Required := True;
978 Set_Is_Delayed_Aspect (Aspect);
980 when Aspect_Implicit_Dereference =>
982 or else not Has_Discriminants (E)
985 ("Aspect must apply to a type with discriminants", N);
993 Disc := First_Discriminant (E);
994 while Present (Disc) loop
995 if Chars (Expr) = Chars (Disc)
996 and then Ekind (Etype (Disc)) =
997 E_Anonymous_Access_Type
999 Set_Has_Implicit_Dereference (E);
1000 Set_Has_Implicit_Dereference (Disc);
1004 Next_Discriminant (Disc);
1007 -- Error if no proper access discriminant.
1010 ("not an access discriminant of&", Expr, E);
1016 -- Aspects corresponding to attribute definition clauses
1018 when Aspect_Address |
1021 Aspect_Component_Size |
1022 Aspect_External_Tag |
1024 Aspect_Machine_Radix |
1025 Aspect_Object_Size |
1029 Aspect_Storage_Pool |
1030 Aspect_Storage_Size |
1031 Aspect_Stream_Size |
1035 -- Construct the attribute definition clause
1038 Make_Attribute_Definition_Clause (Loc,
1040 Chars => Chars (Id),
1041 Expression => Relocate_Node (Expr));
1043 -- A delay is required except in the common case where
1044 -- the expression is a literal, in which case it is fine
1045 -- to take care of it right away.
1047 if Nkind_In (Expr, N_Integer_Literal, N_String_Literal) then
1048 Delay_Required := False;
1050 Delay_Required := True;
1051 Set_Is_Delayed_Aspect (Aspect);
1054 -- Aspects corresponding to pragmas with two arguments, where
1055 -- the first argument is a local name referring to the entity,
1056 -- and the second argument is the aspect definition expression
1057 -- which is an expression that does not get analyzed.
1059 when Aspect_Suppress |
1060 Aspect_Unsuppress =>
1062 -- Construct the pragma
1066 Pragma_Argument_Associations => New_List (
1067 New_Occurrence_Of (E, Loc),
1068 Relocate_Node (Expr)),
1069 Pragma_Identifier =>
1070 Make_Identifier (Sloc (Id), Chars (Id)));
1072 -- We don't have to play the delay game here, since the only
1073 -- values are check names which don't get analyzed anyway.
1075 Delay_Required := False;
1077 -- Aspects corresponding to pragmas with two arguments, where
1078 -- the second argument is a local name referring to the entity,
1079 -- and the first argument is the aspect definition expression.
1081 when Aspect_Warnings =>
1083 -- Construct the pragma
1087 Pragma_Argument_Associations => New_List (
1088 Relocate_Node (Expr),
1089 New_Occurrence_Of (E, Loc)),
1090 Pragma_Identifier =>
1091 Make_Identifier (Sloc (Id), Chars (Id)),
1092 Class_Present => Class_Present (Aspect));
1094 -- We don't have to play the delay game here, since the only
1095 -- values are ON/OFF which don't get analyzed anyway.
1097 Delay_Required := False;
1099 -- Default_Value and Default_Component_Value aspects. These
1100 -- are specially handled because they have no corresponding
1101 -- pragmas or attributes.
1103 when Aspect_Default_Value | Aspect_Default_Component_Value =>
1104 Error_Msg_Name_1 := Chars (Id);
1106 if not Is_Type (E) then
1107 Error_Msg_N ("aspect% can only apply to a type", Id);
1110 elsif not Is_First_Subtype (E) then
1111 Error_Msg_N ("aspect% cannot apply to subtype", Id);
1114 elsif A_Id = Aspect_Default_Value
1115 and then not Is_Scalar_Type (E)
1118 ("aspect% can only be applied to scalar type", Id);
1121 elsif A_Id = Aspect_Default_Component_Value then
1122 if not Is_Array_Type (E) then
1124 ("aspect% can only be applied to array type", Id);
1126 elsif not Is_Scalar_Type (Component_Type (E)) then
1128 ("aspect% requires scalar components", Id);
1134 Delay_Required := True;
1135 Set_Is_Delayed_Aspect (Aspect);
1136 Set_Has_Default_Aspect (Base_Type (Entity (Ent)));
1138 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
1139 -- with a first argument that is the expression, and a second
1140 -- argument that is an informative message if the test fails.
1141 -- This is inserted right after the declaration, to get the
1142 -- required pragma placement. The processing for the pragmas
1143 -- takes care of the required delay.
1145 when Pre_Post_Aspects => declare
1149 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
1150 Pname := Name_Precondition;
1152 Pname := Name_Postcondition;
1155 -- If the expressions is of the form A and then B, then
1156 -- we generate separate Pre/Post aspects for the separate
1157 -- clauses. Since we allow multiple pragmas, there is no
1158 -- problem in allowing multiple Pre/Post aspects internally.
1159 -- These should be treated in reverse order (B first and
1160 -- A second) since they are later inserted just after N in
1161 -- the order they are treated. This way, the pragma for A
1162 -- ends up preceding the pragma for B, which may have an
1163 -- importance for the error raised (either constraint error
1164 -- or precondition error).
1166 -- We do not do this for Pre'Class, since we have to put
1167 -- these conditions together in a complex OR expression
1169 if Pname = Name_Postcondition
1170 or else not Class_Present (Aspect)
1172 while Nkind (Expr) = N_And_Then loop
1173 Insert_After (Aspect,
1174 Make_Aspect_Specification (Sloc (Left_Opnd (Expr)),
1175 Identifier => Identifier (Aspect),
1176 Expression => Relocate_Node (Left_Opnd (Expr)),
1177 Class_Present => Class_Present (Aspect),
1178 Split_PPC => True));
1179 Rewrite (Expr, Relocate_Node (Right_Opnd (Expr)));
1180 Eloc := Sloc (Expr);
1184 -- Build the precondition/postcondition pragma
1188 Pragma_Identifier =>
1189 Make_Identifier (Sloc (Id), Pname),
1190 Class_Present => Class_Present (Aspect),
1191 Split_PPC => Split_PPC (Aspect),
1192 Pragma_Argument_Associations => New_List (
1193 Make_Pragma_Argument_Association (Eloc,
1194 Chars => Name_Check,
1195 Expression => Relocate_Node (Expr))));
1197 -- Add message unless exception messages are suppressed
1199 if not Opt.Exception_Locations_Suppressed then
1200 Append_To (Pragma_Argument_Associations (Aitem),
1201 Make_Pragma_Argument_Association (Eloc,
1202 Chars => Name_Message,
1204 Make_String_Literal (Eloc,
1206 & Get_Name_String (Pname)
1208 & Build_Location_String (Eloc))));
1211 Set_From_Aspect_Specification (Aitem, True);
1212 Set_Is_Delayed_Aspect (Aspect);
1214 -- For Pre/Post cases, insert immediately after the entity
1215 -- declaration, since that is the required pragma placement.
1216 -- Note that for these aspects, we do not have to worry
1217 -- about delay issues, since the pragmas themselves deal
1218 -- with delay of visibility for the expression analysis.
1220 -- If the entity is a library-level subprogram, the pre/
1221 -- postconditions must be treated as late pragmas.
1223 if Nkind (Parent (N)) = N_Compilation_Unit then
1224 Add_Global_Declaration (Aitem);
1226 Insert_After (N, Aitem);
1232 -- Invariant aspects generate a corresponding pragma with a
1233 -- first argument that is the entity, a second argument that is
1234 -- the expression and a third argument that is an appropriate
1235 -- message. This is inserted right after the declaration, to
1236 -- get the required pragma placement. The pragma processing
1237 -- takes care of the required delay.
1239 when Aspect_Invariant |
1240 Aspect_Type_Invariant =>
1242 -- Check placement legality
1244 if not Nkind_In (N, N_Private_Type_Declaration,
1245 N_Private_Extension_Declaration)
1248 ("invariant aspect must apply to a private type", N);
1251 -- Construct the pragma
1255 Pragma_Argument_Associations =>
1256 New_List (Ent, Relocate_Node (Expr)),
1257 Class_Present => Class_Present (Aspect),
1258 Pragma_Identifier =>
1259 Make_Identifier (Sloc (Id), Name_Invariant));
1261 -- Add message unless exception messages are suppressed
1263 if not Opt.Exception_Locations_Suppressed then
1264 Append_To (Pragma_Argument_Associations (Aitem),
1265 Make_Pragma_Argument_Association (Eloc,
1266 Chars => Name_Message,
1268 Make_String_Literal (Eloc,
1269 Strval => "failed invariant from "
1270 & Build_Location_String (Eloc))));
1273 Set_From_Aspect_Specification (Aitem, True);
1274 Set_Is_Delayed_Aspect (Aspect);
1276 -- For Invariant case, insert immediately after the entity
1277 -- declaration. We do not have to worry about delay issues
1278 -- since the pragma processing takes care of this.
1280 Insert_After (N, Aitem);
1283 -- Predicate aspects generate a corresponding pragma with a
1284 -- first argument that is the entity, and the second argument
1285 -- is the expression.
1287 when Aspect_Dynamic_Predicate |
1289 Aspect_Static_Predicate =>
1291 -- Construct the pragma (always a pragma Predicate, with
1292 -- flags recording whether it is static/dynamic).
1296 Pragma_Argument_Associations =>
1297 New_List (Ent, Relocate_Node (Expr)),
1298 Class_Present => Class_Present (Aspect),
1299 Pragma_Identifier =>
1300 Make_Identifier (Sloc (Id), Name_Predicate));
1302 Set_From_Aspect_Specification (Aitem, True);
1304 -- Set special flags for dynamic/static cases
1306 if A_Id = Aspect_Dynamic_Predicate then
1307 Set_From_Dynamic_Predicate (Aitem);
1308 elsif A_Id = Aspect_Static_Predicate then
1309 Set_From_Static_Predicate (Aitem);
1312 -- Make sure we have a freeze node (it might otherwise be
1313 -- missing in cases like subtype X is Y, and we would not
1314 -- have a place to build the predicate function).
1316 Set_Has_Predicates (E);
1318 if Is_Private_Type (E)
1319 and then Present (Full_View (E))
1321 Set_Has_Predicates (Full_View (E));
1322 Set_Has_Delayed_Aspects (Full_View (E));
1325 Ensure_Freeze_Node (E);
1326 Set_Is_Delayed_Aspect (Aspect);
1327 Delay_Required := True;
1329 when Aspect_Test_Case => declare
1331 Comp_Expr : Node_Id;
1332 Comp_Assn : Node_Id;
1337 if Nkind (Expr) /= N_Aggregate then
1339 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1343 Comp_Expr := First (Expressions (Expr));
1344 while Present (Comp_Expr) loop
1345 Append (Relocate_Node (Comp_Expr), Args);
1349 Comp_Assn := First (Component_Associations (Expr));
1350 while Present (Comp_Assn) loop
1351 if List_Length (Choices (Comp_Assn)) /= 1
1353 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
1356 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1360 Append (Make_Pragma_Argument_Association (
1361 Sloc => Sloc (Comp_Assn),
1362 Chars => Chars (First (Choices (Comp_Assn))),
1363 Expression => Relocate_Node (Expression (Comp_Assn))),
1368 -- Build the test-case pragma
1372 Pragma_Identifier =>
1373 Make_Identifier (Sloc (Id), Name_Test_Case),
1374 Pragma_Argument_Associations =>
1377 Set_From_Aspect_Specification (Aitem, True);
1378 Set_Is_Delayed_Aspect (Aspect);
1380 -- Insert immediately after the entity declaration
1382 Insert_After (N, Aitem);
1388 -- If a delay is required, we delay the freeze (not much point in
1389 -- delaying the aspect if we don't delay the freeze!). The pragma
1390 -- or attribute clause if there is one is then attached to the
1391 -- aspect specification which is placed in the rep item list.
1393 if Delay_Required then
1394 if Present (Aitem) then
1395 Set_From_Aspect_Specification (Aitem, True);
1396 Set_Is_Delayed_Aspect (Aitem);
1397 Set_Aspect_Rep_Item (Aspect, Aitem);
1400 Ensure_Freeze_Node (E);
1401 Set_Has_Delayed_Aspects (E);
1402 Record_Rep_Item (E, Aspect);
1404 -- If no delay required, insert the pragma/clause in the tree
1407 Set_From_Aspect_Specification (Aitem, True);
1409 -- If this is a compilation unit, we will put the pragma in
1410 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1412 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1414 Aux : constant Node_Id :=
1415 Aux_Decls_Node (Parent (Ins_Node));
1418 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1420 if No (Pragmas_After (Aux)) then
1421 Set_Pragmas_After (Aux, Empty_List);
1424 -- For Pre_Post put at start of list, otherwise at end
1426 if A_Id in Pre_Post_Aspects then
1427 Prepend (Aitem, Pragmas_After (Aux));
1429 Append (Aitem, Pragmas_After (Aux));
1433 -- Here if not compilation unit case
1436 -- For Pre/Post cases, insert immediately after the entity
1437 -- declaration, since that is the required pragma placement.
1439 if A_Id in Pre_Post_Aspects then
1440 Insert_After (N, Aitem);
1442 -- For all other cases, insert in sequence
1445 Insert_After (Ins_Node, Aitem);
1454 end loop Aspect_Loop;
1455 end Analyze_Aspect_Specifications;
1457 -----------------------
1458 -- Analyze_At_Clause --
1459 -----------------------
1461 -- An at clause is replaced by the corresponding Address attribute
1462 -- definition clause that is the preferred approach in Ada 95.
1464 procedure Analyze_At_Clause (N : Node_Id) is
1465 CS : constant Boolean := Comes_From_Source (N);
1468 -- This is an obsolescent feature
1470 Check_Restriction (No_Obsolescent_Features, N);
1472 if Warn_On_Obsolescent_Feature then
1474 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1476 ("\use address attribute definition clause instead?", N);
1479 -- Rewrite as address clause
1482 Make_Attribute_Definition_Clause (Sloc (N),
1483 Name => Identifier (N),
1484 Chars => Name_Address,
1485 Expression => Expression (N)));
1487 -- We preserve Comes_From_Source, since logically the clause still
1488 -- comes from the source program even though it is changed in form.
1490 Set_Comes_From_Source (N, CS);
1492 -- Analyze rewritten clause
1494 Analyze_Attribute_Definition_Clause (N);
1495 end Analyze_At_Clause;
1497 -----------------------------------------
1498 -- Analyze_Attribute_Definition_Clause --
1499 -----------------------------------------
1501 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1502 Loc : constant Source_Ptr := Sloc (N);
1503 Nam : constant Node_Id := Name (N);
1504 Attr : constant Name_Id := Chars (N);
1505 Expr : constant Node_Id := Expression (N);
1506 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1509 -- The entity of Nam after it is analyzed. In the case of an incomplete
1510 -- type, this is the underlying type.
1513 -- The underlying entity to which the attribute applies. Generally this
1514 -- is the Underlying_Type of Ent, except in the case where the clause
1515 -- applies to full view of incomplete type or private type in which case
1516 -- U_Ent is just a copy of Ent.
1518 FOnly : Boolean := False;
1519 -- Reset to True for subtype specific attribute (Alignment, Size)
1520 -- and for stream attributes, i.e. those cases where in the call
1521 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1522 -- rules are checked. Note that the case of stream attributes is not
1523 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1524 -- disallow Storage_Size for derived task types, but that is also
1525 -- clearly unintentional.
1527 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1528 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1529 -- definition clauses.
1531 function Duplicate_Clause return Boolean;
1532 -- This routine checks if the aspect for U_Ent being given by attribute
1533 -- definition clause N is for an aspect that has already been specified,
1534 -- and if so gives an error message. If there is a duplicate, True is
1535 -- returned, otherwise if there is no error, False is returned.
1537 procedure Check_Indexing_Functions;
1538 -- Check that the function in Constant_Indexing or Variable_Indexing
1539 -- attribute has the proper type structure. If the name is overloaded,
1540 -- check that all interpretations are legal.
1542 procedure Check_Iterator_Functions;
1543 -- Check that there is a single function in Default_Iterator attribute
1544 -- has the proper type structure.
1546 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
1547 -- Common legality check for the previoous two
1549 -----------------------------------
1550 -- Analyze_Stream_TSS_Definition --
1551 -----------------------------------
1553 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1554 Subp : Entity_Id := Empty;
1559 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1560 -- True for Read attribute, false for other attributes
1562 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1563 -- Return true if the entity is a subprogram with an appropriate
1564 -- profile for the attribute being defined.
1566 ----------------------
1567 -- Has_Good_Profile --
1568 ----------------------
1570 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1572 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1573 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1574 (False => E_Procedure, True => E_Function);
1578 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1582 F := First_Formal (Subp);
1585 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1586 or else Designated_Type (Etype (F)) /=
1587 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1592 if not Is_Function then
1596 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1597 (False => E_In_Parameter,
1598 True => E_Out_Parameter);
1600 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1608 Typ := Etype (Subp);
1611 return Base_Type (Typ) = Base_Type (Ent)
1612 and then No (Next_Formal (F));
1613 end Has_Good_Profile;
1615 -- Start of processing for Analyze_Stream_TSS_Definition
1620 if not Is_Type (U_Ent) then
1621 Error_Msg_N ("local name must be a subtype", Nam);
1625 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1627 -- If Pnam is present, it can be either inherited from an ancestor
1628 -- type (in which case it is legal to redefine it for this type), or
1629 -- be a previous definition of the attribute for the same type (in
1630 -- which case it is illegal).
1632 -- In the first case, it will have been analyzed already, and we
1633 -- can check that its profile does not match the expected profile
1634 -- for a stream attribute of U_Ent. In the second case, either Pnam
1635 -- has been analyzed (and has the expected profile), or it has not
1636 -- been analyzed yet (case of a type that has not been frozen yet
1637 -- and for which the stream attribute has been set using Set_TSS).
1640 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1642 Error_Msg_Sloc := Sloc (Pnam);
1643 Error_Msg_Name_1 := Attr;
1644 Error_Msg_N ("% attribute already defined #", Nam);
1650 if Is_Entity_Name (Expr) then
1651 if not Is_Overloaded (Expr) then
1652 if Has_Good_Profile (Entity (Expr)) then
1653 Subp := Entity (Expr);
1657 Get_First_Interp (Expr, I, It);
1658 while Present (It.Nam) loop
1659 if Has_Good_Profile (It.Nam) then
1664 Get_Next_Interp (I, It);
1669 if Present (Subp) then
1670 if Is_Abstract_Subprogram (Subp) then
1671 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1675 Set_Entity (Expr, Subp);
1676 Set_Etype (Expr, Etype (Subp));
1678 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1681 Error_Msg_Name_1 := Attr;
1682 Error_Msg_N ("incorrect expression for% attribute", Expr);
1684 end Analyze_Stream_TSS_Definition;
1686 ------------------------------
1687 -- Check_Indexing_Functions --
1688 ------------------------------
1690 procedure Check_Indexing_Functions is
1692 procedure Check_One_Function (Subp : Entity_Id);
1693 -- Check one possible interpretation
1695 ------------------------
1696 -- Check_One_Function --
1697 ------------------------
1699 procedure Check_One_Function (Subp : Entity_Id) is
1701 if not Check_Primitive_Function (Subp) then
1703 ("aspect Indexing requires a function that applies to type&",
1707 if not Has_Implicit_Dereference (Etype (Subp)) then
1709 ("function for indexing must return a reference type", Subp);
1711 end Check_One_Function;
1713 -- Start of processing for Check_Indexing_Functions
1722 if not Is_Overloaded (Expr) then
1723 Check_One_Function (Entity (Expr));
1731 Get_First_Interp (Expr, I, It);
1732 while Present (It.Nam) loop
1734 -- Note that analysis will have added the interpretation
1735 -- that corresponds to the dereference. We only check the
1736 -- subprogram itself.
1738 if Is_Overloadable (It.Nam) then
1739 Check_One_Function (It.Nam);
1742 Get_Next_Interp (I, It);
1746 end Check_Indexing_Functions;
1748 ------------------------------
1749 -- Check_Iterator_Functions --
1750 ------------------------------
1752 procedure Check_Iterator_Functions is
1753 Default : Entity_Id;
1755 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
1756 -- Check one possible interpretation for validity
1758 ----------------------------
1759 -- Valid_Default_Iterator --
1760 ----------------------------
1762 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
1766 if not Check_Primitive_Function (Subp) then
1769 Formal := First_Formal (Subp);
1772 -- False if any subsequent formal has no default expression
1774 Formal := Next_Formal (Formal);
1775 while Present (Formal) loop
1776 if No (Expression (Parent (Formal))) then
1780 Next_Formal (Formal);
1783 -- True if all subsequent formals have default expressions
1786 end Valid_Default_Iterator;
1788 -- Start of processing for Check_Iterator_Functions
1793 if not Is_Entity_Name (Expr) then
1794 Error_Msg_N ("aspect Iterator must be a function name", Expr);
1797 if not Is_Overloaded (Expr) then
1798 if not Check_Primitive_Function (Entity (Expr)) then
1800 ("aspect Indexing requires a function that applies to type&",
1801 Entity (Expr), Ent);
1804 if not Valid_Default_Iterator (Entity (Expr)) then
1805 Error_Msg_N ("improper function for default iterator", Expr);
1815 Get_First_Interp (Expr, I, It);
1816 while Present (It.Nam) loop
1817 if not Check_Primitive_Function (It.Nam)
1818 or else Valid_Default_Iterator (It.Nam)
1822 elsif Present (Default) then
1823 Error_Msg_N ("default iterator must be unique", Expr);
1829 Get_Next_Interp (I, It);
1833 if Present (Default) then
1834 Set_Entity (Expr, Default);
1835 Set_Is_Overloaded (Expr, False);
1838 end Check_Iterator_Functions;
1840 -------------------------------
1841 -- Check_Primitive_Function --
1842 -------------------------------
1844 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
1848 if Ekind (Subp) /= E_Function then
1852 if No (First_Formal (Subp)) then
1855 Ctrl := Etype (First_Formal (Subp));
1859 or else Ctrl = Class_Wide_Type (Ent)
1861 (Ekind (Ctrl) = E_Anonymous_Access_Type
1863 (Designated_Type (Ctrl) = Ent
1864 or else Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
1873 end Check_Primitive_Function;
1875 ----------------------
1876 -- Duplicate_Clause --
1877 ----------------------
1879 function Duplicate_Clause return Boolean is
1883 -- Nothing to do if this attribute definition clause comes from
1884 -- an aspect specification, since we could not be duplicating an
1885 -- explicit clause, and we dealt with the case of duplicated aspects
1886 -- in Analyze_Aspect_Specifications.
1888 if From_Aspect_Specification (N) then
1892 -- Otherwise current clause may duplicate previous clause or a
1893 -- previously given aspect specification for the same aspect.
1895 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
1898 if Entity (A) = U_Ent then
1899 Error_Msg_Name_1 := Chars (N);
1900 Error_Msg_Sloc := Sloc (A);
1901 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
1907 end Duplicate_Clause;
1909 -- Start of processing for Analyze_Attribute_Definition_Clause
1912 -- The following code is a defense against recursion. Not clear that
1913 -- this can happen legitimately, but perhaps some error situations
1914 -- can cause it, and we did see this recursion during testing.
1916 if Analyzed (N) then
1919 Set_Analyzed (N, True);
1922 -- Process Ignore_Rep_Clauses option (we also ignore rep clauses in
1923 -- CodePeer mode, since they are not relevant in that context).
1925 if Ignore_Rep_Clauses or CodePeer_Mode then
1928 -- The following should be ignored. They do not affect legality
1929 -- and may be target dependent. The basic idea of -gnatI is to
1930 -- ignore any rep clauses that may be target dependent but do not
1931 -- affect legality (except possibly to be rejected because they
1932 -- are incompatible with the compilation target).
1934 when Attribute_Alignment |
1935 Attribute_Bit_Order |
1936 Attribute_Component_Size |
1937 Attribute_Machine_Radix |
1938 Attribute_Object_Size |
1940 Attribute_Stream_Size |
1941 Attribute_Value_Size =>
1942 Rewrite (N, Make_Null_Statement (Sloc (N)));
1945 -- We do not want too ignore 'Small in CodePeer_Mode, since it
1946 -- has an impact on the exact computations performed.
1948 -- Perhaps 'Small should also not be ignored by
1949 -- Ignore_Rep_Clauses ???
1951 when Attribute_Small =>
1952 if Ignore_Rep_Clauses then
1953 Rewrite (N, Make_Null_Statement (Sloc (N)));
1957 -- The following should not be ignored, because in the first place
1958 -- they are reasonably portable, and should not cause problems in
1959 -- compiling code from another target, and also they do affect
1960 -- legality, e.g. failing to provide a stream attribute for a
1961 -- type may make a program illegal.
1963 when Attribute_External_Tag |
1967 Attribute_Storage_Pool |
1968 Attribute_Storage_Size |
1972 -- Other cases are errors ("attribute& cannot be set with
1973 -- definition clause"), which will be caught below.
1981 Ent := Entity (Nam);
1983 if Rep_Item_Too_Early (Ent, N) then
1987 -- Rep clause applies to full view of incomplete type or private type if
1988 -- we have one (if not, this is a premature use of the type). However,
1989 -- certain semantic checks need to be done on the specified entity (i.e.
1990 -- the private view), so we save it in Ent.
1992 if Is_Private_Type (Ent)
1993 and then Is_Derived_Type (Ent)
1994 and then not Is_Tagged_Type (Ent)
1995 and then No (Full_View (Ent))
1997 -- If this is a private type whose completion is a derivation from
1998 -- another private type, there is no full view, and the attribute
1999 -- belongs to the type itself, not its underlying parent.
2003 elsif Ekind (Ent) = E_Incomplete_Type then
2005 -- The attribute applies to the full view, set the entity of the
2006 -- attribute definition accordingly.
2008 Ent := Underlying_Type (Ent);
2010 Set_Entity (Nam, Ent);
2013 U_Ent := Underlying_Type (Ent);
2016 -- Complete other routine error checks
2018 if Etype (Nam) = Any_Type then
2021 elsif Scope (Ent) /= Current_Scope then
2022 Error_Msg_N ("entity must be declared in this scope", Nam);
2025 elsif No (U_Ent) then
2028 elsif Is_Type (U_Ent)
2029 and then not Is_First_Subtype (U_Ent)
2030 and then Id /= Attribute_Object_Size
2031 and then Id /= Attribute_Value_Size
2032 and then not From_At_Mod (N)
2034 Error_Msg_N ("cannot specify attribute for subtype", Nam);
2038 Set_Entity (N, U_Ent);
2040 -- Switch on particular attribute
2048 -- Address attribute definition clause
2050 when Attribute_Address => Address : begin
2052 -- A little error check, catch for X'Address use X'Address;
2054 if Nkind (Nam) = N_Identifier
2055 and then Nkind (Expr) = N_Attribute_Reference
2056 and then Attribute_Name (Expr) = Name_Address
2057 and then Nkind (Prefix (Expr)) = N_Identifier
2058 and then Chars (Nam) = Chars (Prefix (Expr))
2061 ("address for & is self-referencing", Prefix (Expr), Ent);
2065 -- Not that special case, carry on with analysis of expression
2067 Analyze_And_Resolve (Expr, RTE (RE_Address));
2069 -- Even when ignoring rep clauses we need to indicate that the
2070 -- entity has an address clause and thus it is legal to declare
2073 if Ignore_Rep_Clauses then
2074 if Ekind_In (U_Ent, E_Variable, E_Constant) then
2075 Record_Rep_Item (U_Ent, N);
2081 if Duplicate_Clause then
2084 -- Case of address clause for subprogram
2086 elsif Is_Subprogram (U_Ent) then
2087 if Has_Homonym (U_Ent) then
2089 ("address clause cannot be given " &
2090 "for overloaded subprogram",
2095 -- For subprograms, all address clauses are permitted, and we
2096 -- mark the subprogram as having a deferred freeze so that Gigi
2097 -- will not elaborate it too soon.
2099 -- Above needs more comments, what is too soon about???
2101 Set_Has_Delayed_Freeze (U_Ent);
2103 -- Case of address clause for entry
2105 elsif Ekind (U_Ent) = E_Entry then
2106 if Nkind (Parent (N)) = N_Task_Body then
2108 ("entry address must be specified in task spec", Nam);
2112 -- For entries, we require a constant address
2114 Check_Constant_Address_Clause (Expr, U_Ent);
2116 -- Special checks for task types
2118 if Is_Task_Type (Scope (U_Ent))
2119 and then Comes_From_Source (Scope (U_Ent))
2122 ("?entry address declared for entry in task type", N);
2124 ("\?only one task can be declared of this type", N);
2127 -- Entry address clauses are obsolescent
2129 Check_Restriction (No_Obsolescent_Features, N);
2131 if Warn_On_Obsolescent_Feature then
2133 ("attaching interrupt to task entry is an " &
2134 "obsolescent feature (RM J.7.1)?", N);
2136 ("\use interrupt procedure instead?", N);
2139 -- Case of an address clause for a controlled object which we
2140 -- consider to be erroneous.
2142 elsif Is_Controlled (Etype (U_Ent))
2143 or else Has_Controlled_Component (Etype (U_Ent))
2146 ("?controlled object& must not be overlaid", Nam, U_Ent);
2148 ("\?Program_Error will be raised at run time", Nam);
2149 Insert_Action (Declaration_Node (U_Ent),
2150 Make_Raise_Program_Error (Loc,
2151 Reason => PE_Overlaid_Controlled_Object));
2154 -- Case of address clause for a (non-controlled) object
2157 Ekind (U_Ent) = E_Variable
2159 Ekind (U_Ent) = E_Constant
2162 Expr : constant Node_Id := Expression (N);
2167 -- Exported variables cannot have an address clause, because
2168 -- this cancels the effect of the pragma Export.
2170 if Is_Exported (U_Ent) then
2172 ("cannot export object with address clause", Nam);
2176 Find_Overlaid_Entity (N, O_Ent, Off);
2178 -- Overlaying controlled objects is erroneous
2181 and then (Has_Controlled_Component (Etype (O_Ent))
2182 or else Is_Controlled (Etype (O_Ent)))
2185 ("?cannot overlay with controlled object", Expr);
2187 ("\?Program_Error will be raised at run time", Expr);
2188 Insert_Action (Declaration_Node (U_Ent),
2189 Make_Raise_Program_Error (Loc,
2190 Reason => PE_Overlaid_Controlled_Object));
2193 elsif Present (O_Ent)
2194 and then Ekind (U_Ent) = E_Constant
2195 and then not Is_Constant_Object (O_Ent)
2197 Error_Msg_N ("constant overlays a variable?", Expr);
2199 elsif Present (Renamed_Object (U_Ent)) then
2201 ("address clause not allowed"
2202 & " for a renaming declaration (RM 13.1(6))", Nam);
2205 -- Imported variables can have an address clause, but then
2206 -- the import is pretty meaningless except to suppress
2207 -- initializations, so we do not need such variables to
2208 -- be statically allocated (and in fact it causes trouble
2209 -- if the address clause is a local value).
2211 elsif Is_Imported (U_Ent) then
2212 Set_Is_Statically_Allocated (U_Ent, False);
2215 -- We mark a possible modification of a variable with an
2216 -- address clause, since it is likely aliasing is occurring.
2218 Note_Possible_Modification (Nam, Sure => False);
2220 -- Here we are checking for explicit overlap of one variable
2221 -- by another, and if we find this then mark the overlapped
2222 -- variable as also being volatile to prevent unwanted
2223 -- optimizations. This is a significant pessimization so
2224 -- avoid it when there is an offset, i.e. when the object
2225 -- is composite; they cannot be optimized easily anyway.
2228 and then Is_Object (O_Ent)
2231 Set_Treat_As_Volatile (O_Ent);
2234 -- Legality checks on the address clause for initialized
2235 -- objects is deferred until the freeze point, because
2236 -- a subsequent pragma might indicate that the object is
2237 -- imported and thus not initialized.
2239 Set_Has_Delayed_Freeze (U_Ent);
2241 -- If an initialization call has been generated for this
2242 -- object, it needs to be deferred to after the freeze node
2243 -- we have just now added, otherwise GIGI will see a
2244 -- reference to the variable (as actual to the IP call)
2245 -- before its definition.
2248 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
2250 if Present (Init_Call) then
2252 Append_Freeze_Action (U_Ent, Init_Call);
2256 if Is_Exported (U_Ent) then
2258 ("& cannot be exported if an address clause is given",
2261 ("\define and export a variable " &
2262 "that holds its address instead",
2266 -- Entity has delayed freeze, so we will generate an
2267 -- alignment check at the freeze point unless suppressed.
2269 if not Range_Checks_Suppressed (U_Ent)
2270 and then not Alignment_Checks_Suppressed (U_Ent)
2272 Set_Check_Address_Alignment (N);
2275 -- Kill the size check code, since we are not allocating
2276 -- the variable, it is somewhere else.
2278 Kill_Size_Check_Code (U_Ent);
2280 -- If the address clause is of the form:
2282 -- for Y'Address use X'Address
2286 -- Const : constant Address := X'Address;
2288 -- for Y'Address use Const;
2290 -- then we make an entry in the table for checking the size
2291 -- and alignment of the overlaying variable. We defer this
2292 -- check till after code generation to take full advantage
2293 -- of the annotation done by the back end. This entry is
2294 -- only made if the address clause comes from source.
2296 -- If the entity has a generic type, the check will be
2297 -- performed in the instance if the actual type justifies
2298 -- it, and we do not insert the clause in the table to
2299 -- prevent spurious warnings.
2301 if Address_Clause_Overlay_Warnings
2302 and then Comes_From_Source (N)
2303 and then Present (O_Ent)
2304 and then Is_Object (O_Ent)
2306 if not Is_Generic_Type (Etype (U_Ent)) then
2307 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
2310 -- If variable overlays a constant view, and we are
2311 -- warning on overlays, then mark the variable as
2312 -- overlaying a constant (we will give warnings later
2313 -- if this variable is assigned).
2315 if Is_Constant_Object (O_Ent)
2316 and then Ekind (U_Ent) = E_Variable
2318 Set_Overlays_Constant (U_Ent);
2323 -- Not a valid entity for an address clause
2326 Error_Msg_N ("address cannot be given for &", Nam);
2334 -- Alignment attribute definition clause
2336 when Attribute_Alignment => Alignment : declare
2337 Align : constant Uint := Get_Alignment_Value (Expr);
2342 if not Is_Type (U_Ent)
2343 and then Ekind (U_Ent) /= E_Variable
2344 and then Ekind (U_Ent) /= E_Constant
2346 Error_Msg_N ("alignment cannot be given for &", Nam);
2348 elsif Duplicate_Clause then
2351 elsif Align /= No_Uint then
2352 Set_Has_Alignment_Clause (U_Ent);
2353 Set_Alignment (U_Ent, Align);
2355 -- For an array type, U_Ent is the first subtype. In that case,
2356 -- also set the alignment of the anonymous base type so that
2357 -- other subtypes (such as the itypes for aggregates of the
2358 -- type) also receive the expected alignment.
2360 if Is_Array_Type (U_Ent) then
2361 Set_Alignment (Base_Type (U_Ent), Align);
2370 -- Bit_Order attribute definition clause
2372 when Attribute_Bit_Order => Bit_Order : declare
2374 if not Is_Record_Type (U_Ent) then
2376 ("Bit_Order can only be defined for record type", Nam);
2378 elsif Duplicate_Clause then
2382 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
2384 if Etype (Expr) = Any_Type then
2387 elsif not Is_Static_Expression (Expr) then
2388 Flag_Non_Static_Expr
2389 ("Bit_Order requires static expression!", Expr);
2392 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
2393 Set_Reverse_Bit_Order (U_Ent, True);
2399 --------------------
2400 -- Component_Size --
2401 --------------------
2403 -- Component_Size attribute definition clause
2405 when Attribute_Component_Size => Component_Size_Case : declare
2406 Csize : constant Uint := Static_Integer (Expr);
2410 New_Ctyp : Entity_Id;
2414 if not Is_Array_Type (U_Ent) then
2415 Error_Msg_N ("component size requires array type", Nam);
2419 Btype := Base_Type (U_Ent);
2420 Ctyp := Component_Type (Btype);
2422 if Duplicate_Clause then
2425 elsif Rep_Item_Too_Early (Btype, N) then
2428 elsif Csize /= No_Uint then
2429 Check_Size (Expr, Ctyp, Csize, Biased);
2431 -- For the biased case, build a declaration for a subtype that
2432 -- will be used to represent the biased subtype that reflects
2433 -- the biased representation of components. We need the subtype
2434 -- to get proper conversions on referencing elements of the
2435 -- array. Note: component size clauses are ignored in VM mode.
2437 if VM_Target = No_VM then
2440 Make_Defining_Identifier (Loc,
2442 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2445 Make_Subtype_Declaration (Loc,
2446 Defining_Identifier => New_Ctyp,
2447 Subtype_Indication =>
2448 New_Occurrence_Of (Component_Type (Btype), Loc));
2450 Set_Parent (Decl, N);
2451 Analyze (Decl, Suppress => All_Checks);
2453 Set_Has_Delayed_Freeze (New_Ctyp, False);
2454 Set_Esize (New_Ctyp, Csize);
2455 Set_RM_Size (New_Ctyp, Csize);
2456 Init_Alignment (New_Ctyp);
2457 Set_Is_Itype (New_Ctyp, True);
2458 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2460 Set_Component_Type (Btype, New_Ctyp);
2461 Set_Biased (New_Ctyp, N, "component size clause");
2464 Set_Component_Size (Btype, Csize);
2466 -- For VM case, we ignore component size clauses
2469 -- Give a warning unless we are in GNAT mode, in which case
2470 -- the warning is suppressed since it is not useful.
2472 if not GNAT_Mode then
2474 ("?component size ignored in this configuration", N);
2478 -- Deal with warning on overridden size
2480 if Warn_On_Overridden_Size
2481 and then Has_Size_Clause (Ctyp)
2482 and then RM_Size (Ctyp) /= Csize
2485 ("?component size overrides size clause for&",
2489 Set_Has_Component_Size_Clause (Btype, True);
2490 Set_Has_Non_Standard_Rep (Btype, True);
2492 end Component_Size_Case;
2494 -----------------------
2495 -- Constant_Indexing --
2496 -----------------------
2498 when Attribute_Constant_Indexing =>
2499 Check_Indexing_Functions;
2501 ----------------------
2502 -- Default_Iterator --
2503 ----------------------
2505 when Attribute_Default_Iterator => Default_Iterator : declare
2509 if not Is_Tagged_Type (U_Ent) then
2511 ("aspect Default_Iterator applies to tagged type", Nam);
2514 Check_Iterator_Functions;
2518 if not Is_Entity_Name (Expr)
2519 or else Ekind (Entity (Expr)) /= E_Function
2521 Error_Msg_N ("aspect Iterator must be a function", Expr);
2523 Func := Entity (Expr);
2526 if No (First_Formal (Func))
2527 or else Etype (First_Formal (Func)) /= U_Ent
2530 ("Default Iterator must be a primitive of&", Func, U_Ent);
2532 end Default_Iterator;
2538 when Attribute_External_Tag => External_Tag :
2540 if not Is_Tagged_Type (U_Ent) then
2541 Error_Msg_N ("should be a tagged type", Nam);
2544 if Duplicate_Clause then
2548 Analyze_And_Resolve (Expr, Standard_String);
2550 if not Is_Static_Expression (Expr) then
2551 Flag_Non_Static_Expr
2552 ("static string required for tag name!", Nam);
2555 if VM_Target = No_VM then
2556 Set_Has_External_Tag_Rep_Clause (U_Ent);
2558 Error_Msg_Name_1 := Attr;
2560 ("% attribute unsupported in this configuration", Nam);
2563 if not Is_Library_Level_Entity (U_Ent) then
2565 ("?non-unique external tag supplied for &", N, U_Ent);
2567 ("?\same external tag applies to all subprogram calls", N);
2569 ("?\corresponding internal tag cannot be obtained", N);
2574 --------------------------
2575 -- Implicit_Dereference --
2576 --------------------------
2578 when Attribute_Implicit_Dereference =>
2580 -- Legality checks already performed at the point of
2581 -- the type declaration, aspect is not delayed.
2589 when Attribute_Input =>
2590 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2591 Set_Has_Specified_Stream_Input (Ent);
2593 ----------------------
2594 -- Iterator_Element --
2595 ----------------------
2597 when Attribute_Iterator_Element =>
2600 if not Is_Entity_Name (Expr)
2601 or else not Is_Type (Entity (Expr))
2603 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
2610 -- Machine radix attribute definition clause
2612 when Attribute_Machine_Radix => Machine_Radix : declare
2613 Radix : constant Uint := Static_Integer (Expr);
2616 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2617 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2619 elsif Duplicate_Clause then
2622 elsif Radix /= No_Uint then
2623 Set_Has_Machine_Radix_Clause (U_Ent);
2624 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2628 elsif Radix = 10 then
2629 Set_Machine_Radix_10 (U_Ent);
2631 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2640 -- Object_Size attribute definition clause
2642 when Attribute_Object_Size => Object_Size : declare
2643 Size : constant Uint := Static_Integer (Expr);
2646 pragma Warnings (Off, Biased);
2649 if not Is_Type (U_Ent) then
2650 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2652 elsif Duplicate_Clause then
2656 Check_Size (Expr, U_Ent, Size, Biased);
2664 UI_Mod (Size, 64) /= 0
2667 ("Object_Size must be 8, 16, 32, or multiple of 64",
2671 Set_Esize (U_Ent, Size);
2672 Set_Has_Object_Size_Clause (U_Ent);
2673 Alignment_Check_For_Size_Change (U_Ent, Size);
2681 when Attribute_Output =>
2682 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2683 Set_Has_Specified_Stream_Output (Ent);
2689 when Attribute_Read =>
2690 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2691 Set_Has_Specified_Stream_Read (Ent);
2697 -- Size attribute definition clause
2699 when Attribute_Size => Size : declare
2700 Size : constant Uint := Static_Integer (Expr);
2707 if Duplicate_Clause then
2710 elsif not Is_Type (U_Ent)
2711 and then Ekind (U_Ent) /= E_Variable
2712 and then Ekind (U_Ent) /= E_Constant
2714 Error_Msg_N ("size cannot be given for &", Nam);
2716 elsif Is_Array_Type (U_Ent)
2717 and then not Is_Constrained (U_Ent)
2720 ("size cannot be given for unconstrained array", Nam);
2722 elsif Size /= No_Uint then
2723 if VM_Target /= No_VM and then not GNAT_Mode then
2725 -- Size clause is not handled properly on VM targets.
2726 -- Display a warning unless we are in GNAT mode, in which
2727 -- case this is useless.
2730 ("?size clauses are ignored in this configuration", N);
2733 if Is_Type (U_Ent) then
2736 Etyp := Etype (U_Ent);
2739 -- Check size, note that Gigi is in charge of checking that the
2740 -- size of an array or record type is OK. Also we do not check
2741 -- the size in the ordinary fixed-point case, since it is too
2742 -- early to do so (there may be subsequent small clause that
2743 -- affects the size). We can check the size if a small clause
2744 -- has already been given.
2746 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2747 or else Has_Small_Clause (U_Ent)
2749 Check_Size (Expr, Etyp, Size, Biased);
2750 Set_Biased (U_Ent, N, "size clause", Biased);
2753 -- For types set RM_Size and Esize if possible
2755 if Is_Type (U_Ent) then
2756 Set_RM_Size (U_Ent, Size);
2758 -- For elementary types, increase Object_Size to power of 2,
2759 -- but not less than a storage unit in any case (normally
2760 -- this means it will be byte addressable).
2762 -- For all other types, nothing else to do, we leave Esize
2763 -- (object size) unset, the back end will set it from the
2764 -- size and alignment in an appropriate manner.
2766 -- In both cases, we check whether the alignment must be
2767 -- reset in the wake of the size change.
2769 if Is_Elementary_Type (U_Ent) then
2770 if Size <= System_Storage_Unit then
2771 Init_Esize (U_Ent, System_Storage_Unit);
2772 elsif Size <= 16 then
2773 Init_Esize (U_Ent, 16);
2774 elsif Size <= 32 then
2775 Init_Esize (U_Ent, 32);
2777 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2780 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
2782 Alignment_Check_For_Size_Change (U_Ent, Size);
2785 -- For objects, set Esize only
2788 if Is_Elementary_Type (Etyp) then
2789 if Size /= System_Storage_Unit
2791 Size /= System_Storage_Unit * 2
2793 Size /= System_Storage_Unit * 4
2795 Size /= System_Storage_Unit * 8
2797 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2798 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2800 ("size for primitive object must be a power of 2"
2801 & " in the range ^-^", N);
2805 Set_Esize (U_Ent, Size);
2808 Set_Has_Size_Clause (U_Ent);
2816 -- Small attribute definition clause
2818 when Attribute_Small => Small : declare
2819 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2823 Analyze_And_Resolve (Expr, Any_Real);
2825 if Etype (Expr) = Any_Type then
2828 elsif not Is_Static_Expression (Expr) then
2829 Flag_Non_Static_Expr
2830 ("small requires static expression!", Expr);
2834 Small := Expr_Value_R (Expr);
2836 if Small <= Ureal_0 then
2837 Error_Msg_N ("small value must be greater than zero", Expr);
2843 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2845 ("small requires an ordinary fixed point type", Nam);
2847 elsif Has_Small_Clause (U_Ent) then
2848 Error_Msg_N ("small already given for &", Nam);
2850 elsif Small > Delta_Value (U_Ent) then
2852 ("small value must not be greater then delta value", Nam);
2855 Set_Small_Value (U_Ent, Small);
2856 Set_Small_Value (Implicit_Base, Small);
2857 Set_Has_Small_Clause (U_Ent);
2858 Set_Has_Small_Clause (Implicit_Base);
2859 Set_Has_Non_Standard_Rep (Implicit_Base);
2867 -- Storage_Pool attribute definition clause
2869 when Attribute_Storage_Pool => Storage_Pool : declare
2874 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2876 ("storage pool cannot be given for access-to-subprogram type",
2881 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2884 ("storage pool can only be given for access types", Nam);
2887 elsif Is_Derived_Type (U_Ent) then
2889 ("storage pool cannot be given for a derived access type",
2892 elsif Duplicate_Clause then
2895 elsif Present (Associated_Storage_Pool (U_Ent)) then
2896 Error_Msg_N ("storage pool already given for &", Nam);
2901 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
2903 if not Denotes_Variable (Expr) then
2904 Error_Msg_N ("storage pool must be a variable", Expr);
2908 if Nkind (Expr) = N_Type_Conversion then
2909 T := Etype (Expression (Expr));
2914 -- The Stack_Bounded_Pool is used internally for implementing
2915 -- access types with a Storage_Size. Since it only work properly
2916 -- when used on one specific type, we need to check that it is not
2917 -- hijacked improperly:
2919 -- type T is access Integer;
2920 -- for T'Storage_Size use n;
2921 -- type Q is access Float;
2922 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
2924 if RTE_Available (RE_Stack_Bounded_Pool)
2925 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
2927 Error_Msg_N ("non-shareable internal Pool", Expr);
2931 -- If the argument is a name that is not an entity name, then
2932 -- we construct a renaming operation to define an entity of
2933 -- type storage pool.
2935 if not Is_Entity_Name (Expr)
2936 and then Is_Object_Reference (Expr)
2938 Pool := Make_Temporary (Loc, 'P', Expr);
2941 Rnode : constant Node_Id :=
2942 Make_Object_Renaming_Declaration (Loc,
2943 Defining_Identifier => Pool,
2945 New_Occurrence_Of (Etype (Expr), Loc),
2949 Insert_Before (N, Rnode);
2951 Set_Associated_Storage_Pool (U_Ent, Pool);
2954 elsif Is_Entity_Name (Expr) then
2955 Pool := Entity (Expr);
2957 -- If pool is a renamed object, get original one. This can
2958 -- happen with an explicit renaming, and within instances.
2960 while Present (Renamed_Object (Pool))
2961 and then Is_Entity_Name (Renamed_Object (Pool))
2963 Pool := Entity (Renamed_Object (Pool));
2966 if Present (Renamed_Object (Pool))
2967 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
2968 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
2970 Pool := Entity (Expression (Renamed_Object (Pool)));
2973 Set_Associated_Storage_Pool (U_Ent, Pool);
2975 elsif Nkind (Expr) = N_Type_Conversion
2976 and then Is_Entity_Name (Expression (Expr))
2977 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
2979 Pool := Entity (Expression (Expr));
2980 Set_Associated_Storage_Pool (U_Ent, Pool);
2983 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
2992 -- Storage_Size attribute definition clause
2994 when Attribute_Storage_Size => Storage_Size : declare
2995 Btype : constant Entity_Id := Base_Type (U_Ent);
2999 if Is_Task_Type (U_Ent) then
3000 Check_Restriction (No_Obsolescent_Features, N);
3002 if Warn_On_Obsolescent_Feature then
3004 ("storage size clause for task is an " &
3005 "obsolescent feature (RM J.9)?", N);
3006 Error_Msg_N ("\use Storage_Size pragma instead?", N);
3012 if not Is_Access_Type (U_Ent)
3013 and then Ekind (U_Ent) /= E_Task_Type
3015 Error_Msg_N ("storage size cannot be given for &", Nam);
3017 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
3019 ("storage size cannot be given for a derived access type",
3022 elsif Duplicate_Clause then
3026 Analyze_And_Resolve (Expr, Any_Integer);
3028 if Is_Access_Type (U_Ent) then
3029 if Present (Associated_Storage_Pool (U_Ent)) then
3030 Error_Msg_N ("storage pool already given for &", Nam);
3034 if Is_OK_Static_Expression (Expr)
3035 and then Expr_Value (Expr) = 0
3037 Set_No_Pool_Assigned (Btype);
3040 else -- Is_Task_Type (U_Ent)
3041 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
3043 if Present (Sprag) then
3044 Error_Msg_Sloc := Sloc (Sprag);
3046 ("Storage_Size already specified#", Nam);
3051 Set_Has_Storage_Size_Clause (Btype);
3059 when Attribute_Stream_Size => Stream_Size : declare
3060 Size : constant Uint := Static_Integer (Expr);
3063 if Ada_Version <= Ada_95 then
3064 Check_Restriction (No_Implementation_Attributes, N);
3067 if Duplicate_Clause then
3070 elsif Is_Elementary_Type (U_Ent) then
3071 if Size /= System_Storage_Unit
3073 Size /= System_Storage_Unit * 2
3075 Size /= System_Storage_Unit * 4
3077 Size /= System_Storage_Unit * 8
3079 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
3081 ("stream size for elementary type must be a"
3082 & " power of 2 and at least ^", N);
3084 elsif RM_Size (U_Ent) > Size then
3085 Error_Msg_Uint_1 := RM_Size (U_Ent);
3087 ("stream size for elementary type must be a"
3088 & " power of 2 and at least ^", N);
3091 Set_Has_Stream_Size_Clause (U_Ent);
3094 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
3102 -- Value_Size attribute definition clause
3104 when Attribute_Value_Size => Value_Size : declare
3105 Size : constant Uint := Static_Integer (Expr);
3109 if not Is_Type (U_Ent) then
3110 Error_Msg_N ("Value_Size cannot be given for &", Nam);
3112 elsif Duplicate_Clause then
3115 elsif Is_Array_Type (U_Ent)
3116 and then not Is_Constrained (U_Ent)
3119 ("Value_Size cannot be given for unconstrained array", Nam);
3122 if Is_Elementary_Type (U_Ent) then
3123 Check_Size (Expr, U_Ent, Size, Biased);
3124 Set_Biased (U_Ent, N, "value size clause", Biased);
3127 Set_RM_Size (U_Ent, Size);
3131 -----------------------
3132 -- Variable_Indexing --
3133 -----------------------
3135 when Attribute_Variable_Indexing =>
3136 Check_Indexing_Functions;
3142 when Attribute_Write =>
3143 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
3144 Set_Has_Specified_Stream_Write (Ent);
3146 -- All other attributes cannot be set
3150 ("attribute& cannot be set with definition clause", N);
3153 -- The test for the type being frozen must be performed after any
3154 -- expression the clause has been analyzed since the expression itself
3155 -- might cause freezing that makes the clause illegal.
3157 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
3160 end Analyze_Attribute_Definition_Clause;
3162 ----------------------------
3163 -- Analyze_Code_Statement --
3164 ----------------------------
3166 procedure Analyze_Code_Statement (N : Node_Id) is
3167 HSS : constant Node_Id := Parent (N);
3168 SBody : constant Node_Id := Parent (HSS);
3169 Subp : constant Entity_Id := Current_Scope;
3176 -- Analyze and check we get right type, note that this implements the
3177 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
3178 -- is the only way that Asm_Insn could possibly be visible.
3180 Analyze_And_Resolve (Expression (N));
3182 if Etype (Expression (N)) = Any_Type then
3184 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
3185 Error_Msg_N ("incorrect type for code statement", N);
3189 Check_Code_Statement (N);
3191 -- Make sure we appear in the handled statement sequence of a
3192 -- subprogram (RM 13.8(3)).
3194 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
3195 or else Nkind (SBody) /= N_Subprogram_Body
3198 ("code statement can only appear in body of subprogram", N);
3202 -- Do remaining checks (RM 13.8(3)) if not already done
3204 if not Is_Machine_Code_Subprogram (Subp) then
3205 Set_Is_Machine_Code_Subprogram (Subp);
3207 -- No exception handlers allowed
3209 if Present (Exception_Handlers (HSS)) then
3211 ("exception handlers not permitted in machine code subprogram",
3212 First (Exception_Handlers (HSS)));
3215 -- No declarations other than use clauses and pragmas (we allow
3216 -- certain internally generated declarations as well).
3218 Decl := First (Declarations (SBody));
3219 while Present (Decl) loop
3220 DeclO := Original_Node (Decl);
3221 if Comes_From_Source (DeclO)
3222 and not Nkind_In (DeclO, N_Pragma,
3223 N_Use_Package_Clause,
3225 N_Implicit_Label_Declaration)
3228 ("this declaration not allowed in machine code subprogram",
3235 -- No statements other than code statements, pragmas, and labels.
3236 -- Again we allow certain internally generated statements.
3238 Stmt := First (Statements (HSS));
3239 while Present (Stmt) loop
3240 StmtO := Original_Node (Stmt);
3241 if Comes_From_Source (StmtO)
3242 and then not Nkind_In (StmtO, N_Pragma,
3247 ("this statement is not allowed in machine code subprogram",
3254 end Analyze_Code_Statement;
3256 -----------------------------------------------
3257 -- Analyze_Enumeration_Representation_Clause --
3258 -----------------------------------------------
3260 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
3261 Ident : constant Node_Id := Identifier (N);
3262 Aggr : constant Node_Id := Array_Aggregate (N);
3263 Enumtype : Entity_Id;
3270 Err : Boolean := False;
3271 -- Set True to avoid cascade errors and crashes on incorrect source code
3273 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
3274 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
3275 -- Allowed range of universal integer (= allowed range of enum lit vals)
3279 -- Minimum and maximum values of entries
3282 -- Pointer to node for literal providing max value
3285 if Ignore_Rep_Clauses then
3289 -- First some basic error checks
3292 Enumtype := Entity (Ident);
3294 if Enumtype = Any_Type
3295 or else Rep_Item_Too_Early (Enumtype, N)
3299 Enumtype := Underlying_Type (Enumtype);
3302 if not Is_Enumeration_Type (Enumtype) then
3304 ("enumeration type required, found}",
3305 Ident, First_Subtype (Enumtype));
3309 -- Ignore rep clause on generic actual type. This will already have
3310 -- been flagged on the template as an error, and this is the safest
3311 -- way to ensure we don't get a junk cascaded message in the instance.
3313 if Is_Generic_Actual_Type (Enumtype) then
3316 -- Type must be in current scope
3318 elsif Scope (Enumtype) /= Current_Scope then
3319 Error_Msg_N ("type must be declared in this scope", Ident);
3322 -- Type must be a first subtype
3324 elsif not Is_First_Subtype (Enumtype) then
3325 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
3328 -- Ignore duplicate rep clause
3330 elsif Has_Enumeration_Rep_Clause (Enumtype) then
3331 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
3334 -- Don't allow rep clause for standard [wide_[wide_]]character
3336 elsif Is_Standard_Character_Type (Enumtype) then
3337 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
3340 -- Check that the expression is a proper aggregate (no parentheses)
3342 elsif Paren_Count (Aggr) /= 0 then
3344 ("extra parentheses surrounding aggregate not allowed",
3348 -- All tests passed, so set rep clause in place
3351 Set_Has_Enumeration_Rep_Clause (Enumtype);
3352 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
3355 -- Now we process the aggregate. Note that we don't use the normal
3356 -- aggregate code for this purpose, because we don't want any of the
3357 -- normal expansion activities, and a number of special semantic
3358 -- rules apply (including the component type being any integer type)
3360 Elit := First_Literal (Enumtype);
3362 -- First the positional entries if any
3364 if Present (Expressions (Aggr)) then
3365 Expr := First (Expressions (Aggr));
3366 while Present (Expr) loop
3368 Error_Msg_N ("too many entries in aggregate", Expr);
3372 Val := Static_Integer (Expr);
3374 -- Err signals that we found some incorrect entries processing
3375 -- the list. The final checks for completeness and ordering are
3376 -- skipped in this case.
3378 if Val = No_Uint then
3380 elsif Val < Lo or else Hi < Val then
3381 Error_Msg_N ("value outside permitted range", Expr);
3385 Set_Enumeration_Rep (Elit, Val);
3386 Set_Enumeration_Rep_Expr (Elit, Expr);
3392 -- Now process the named entries if present
3394 if Present (Component_Associations (Aggr)) then
3395 Assoc := First (Component_Associations (Aggr));
3396 while Present (Assoc) loop
3397 Choice := First (Choices (Assoc));
3399 if Present (Next (Choice)) then
3401 ("multiple choice not allowed here", Next (Choice));
3405 if Nkind (Choice) = N_Others_Choice then
3406 Error_Msg_N ("others choice not allowed here", Choice);
3409 elsif Nkind (Choice) = N_Range then
3411 -- ??? should allow zero/one element range here
3413 Error_Msg_N ("range not allowed here", Choice);
3417 Analyze_And_Resolve (Choice, Enumtype);
3419 if Error_Posted (Choice) then
3424 if Is_Entity_Name (Choice)
3425 and then Is_Type (Entity (Choice))
3427 Error_Msg_N ("subtype name not allowed here", Choice);
3430 -- ??? should allow static subtype with zero/one entry
3432 elsif Etype (Choice) = Base_Type (Enumtype) then
3433 if not Is_Static_Expression (Choice) then
3434 Flag_Non_Static_Expr
3435 ("non-static expression used for choice!", Choice);
3439 Elit := Expr_Value_E (Choice);
3441 if Present (Enumeration_Rep_Expr (Elit)) then
3443 Sloc (Enumeration_Rep_Expr (Elit));
3445 ("representation for& previously given#",
3450 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
3452 Expr := Expression (Assoc);
3453 Val := Static_Integer (Expr);
3455 if Val = No_Uint then
3458 elsif Val < Lo or else Hi < Val then
3459 Error_Msg_N ("value outside permitted range", Expr);
3463 Set_Enumeration_Rep (Elit, Val);
3473 -- Aggregate is fully processed. Now we check that a full set of
3474 -- representations was given, and that they are in range and in order.
3475 -- These checks are only done if no other errors occurred.
3481 Elit := First_Literal (Enumtype);
3482 while Present (Elit) loop
3483 if No (Enumeration_Rep_Expr (Elit)) then
3484 Error_Msg_NE ("missing representation for&!", N, Elit);
3487 Val := Enumeration_Rep (Elit);
3489 if Min = No_Uint then
3493 if Val /= No_Uint then
3494 if Max /= No_Uint and then Val <= Max then
3496 ("enumeration value for& not ordered!",
3497 Enumeration_Rep_Expr (Elit), Elit);
3500 Max_Node := Enumeration_Rep_Expr (Elit);
3504 -- If there is at least one literal whose representation is not
3505 -- equal to the Pos value, then note that this enumeration type
3506 -- has a non-standard representation.
3508 if Val /= Enumeration_Pos (Elit) then
3509 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3516 -- Now set proper size information
3519 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3522 if Has_Size_Clause (Enumtype) then
3524 -- All OK, if size is OK now
3526 if RM_Size (Enumtype) >= Minsize then
3530 -- Try if we can get by with biasing
3533 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3535 -- Error message if even biasing does not work
3537 if RM_Size (Enumtype) < Minsize then
3538 Error_Msg_Uint_1 := RM_Size (Enumtype);
3539 Error_Msg_Uint_2 := Max;
3541 ("previously given size (^) is too small "
3542 & "for this value (^)", Max_Node);
3544 -- If biasing worked, indicate that we now have biased rep
3548 (Enumtype, Size_Clause (Enumtype), "size clause");
3553 Set_RM_Size (Enumtype, Minsize);
3554 Set_Enum_Esize (Enumtype);
3557 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3558 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3559 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3563 -- We repeat the too late test in case it froze itself!
3565 if Rep_Item_Too_Late (Enumtype, N) then
3568 end Analyze_Enumeration_Representation_Clause;
3570 ----------------------------
3571 -- Analyze_Free_Statement --
3572 ----------------------------
3574 procedure Analyze_Free_Statement (N : Node_Id) is
3576 Analyze (Expression (N));
3577 end Analyze_Free_Statement;
3579 ---------------------------
3580 -- Analyze_Freeze_Entity --
3581 ---------------------------
3583 procedure Analyze_Freeze_Entity (N : Node_Id) is
3584 E : constant Entity_Id := Entity (N);
3587 -- Remember that we are processing a freezing entity. Required to
3588 -- ensure correct decoration of internal entities associated with
3589 -- interfaces (see New_Overloaded_Entity).
3591 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3593 -- For tagged types covering interfaces add internal entities that link
3594 -- the primitives of the interfaces with the primitives that cover them.
3595 -- Note: These entities were originally generated only when generating
3596 -- code because their main purpose was to provide support to initialize
3597 -- the secondary dispatch tables. They are now generated also when
3598 -- compiling with no code generation to provide ASIS the relationship
3599 -- between interface primitives and tagged type primitives. They are
3600 -- also used to locate primitives covering interfaces when processing
3601 -- generics (see Derive_Subprograms).
3603 if Ada_Version >= Ada_2005
3604 and then Ekind (E) = E_Record_Type
3605 and then Is_Tagged_Type (E)
3606 and then not Is_Interface (E)
3607 and then Has_Interfaces (E)
3609 -- This would be a good common place to call the routine that checks
3610 -- overriding of interface primitives (and thus factorize calls to
3611 -- Check_Abstract_Overriding located at different contexts in the
3612 -- compiler). However, this is not possible because it causes
3613 -- spurious errors in case of late overriding.
3615 Add_Internal_Interface_Entities (E);
3620 if Ekind (E) = E_Record_Type
3621 and then Is_CPP_Class (E)
3622 and then Is_Tagged_Type (E)
3623 and then Tagged_Type_Expansion
3624 and then Expander_Active
3626 if CPP_Num_Prims (E) = 0 then
3628 -- If the CPP type has user defined components then it must import
3629 -- primitives from C++. This is required because if the C++ class
3630 -- has no primitives then the C++ compiler does not added the _tag
3631 -- component to the type.
3633 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3635 if First_Entity (E) /= Last_Entity (E) then
3637 ("?'C'P'P type must import at least one primitive from C++",
3642 -- Check that all its primitives are abstract or imported from C++.
3643 -- Check also availability of the C++ constructor.
3646 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3648 Error_Reported : Boolean := False;
3652 Elmt := First_Elmt (Primitive_Operations (E));
3653 while Present (Elmt) loop
3654 Prim := Node (Elmt);
3656 if Comes_From_Source (Prim) then
3657 if Is_Abstract_Subprogram (Prim) then
3660 elsif not Is_Imported (Prim)
3661 or else Convention (Prim) /= Convention_CPP
3664 ("?primitives of 'C'P'P types must be imported from C++"
3665 & " or abstract", Prim);
3667 elsif not Has_Constructors
3668 and then not Error_Reported
3670 Error_Msg_Name_1 := Chars (E);
3672 ("?'C'P'P constructor required for type %", Prim);
3673 Error_Reported := True;
3682 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3684 -- If we have a type with predicates, build predicate function
3686 if Is_Type (E) and then Has_Predicates (E) then
3687 Build_Predicate_Function (E, N);
3690 -- If type has delayed aspects, this is where we do the preanalysis at
3691 -- the freeze point, as part of the consistent visibility check. Note
3692 -- that this must be done after calling Build_Predicate_Function or
3693 -- Build_Invariant_Procedure since these subprograms fix occurrences of
3694 -- the subtype name in the saved expression so that they will not cause
3695 -- trouble in the preanalysis.
3697 if Has_Delayed_Aspects (E) then
3702 -- Look for aspect specification entries for this entity
3704 Ritem := First_Rep_Item (E);
3705 while Present (Ritem) loop
3706 if Nkind (Ritem) = N_Aspect_Specification
3707 and then Entity (Ritem) = E
3708 and then Is_Delayed_Aspect (Ritem)
3709 and then Scope (E) = Current_Scope
3711 Check_Aspect_At_Freeze_Point (Ritem);
3714 Next_Rep_Item (Ritem);
3718 end Analyze_Freeze_Entity;
3720 ------------------------------------------
3721 -- Analyze_Record_Representation_Clause --
3722 ------------------------------------------
3724 -- Note: we check as much as we can here, but we can't do any checks
3725 -- based on the position values (e.g. overlap checks) until freeze time
3726 -- because especially in Ada 2005 (machine scalar mode), the processing
3727 -- for non-standard bit order can substantially change the positions.
3728 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3729 -- for the remainder of this processing.
3731 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3732 Ident : constant Node_Id := Identifier (N);
3737 Hbit : Uint := Uint_0;
3741 Rectype : Entity_Id;
3743 CR_Pragma : Node_Id := Empty;
3744 -- Points to N_Pragma node if Complete_Representation pragma present
3747 if Ignore_Rep_Clauses then
3752 Rectype := Entity (Ident);
3754 if Rectype = Any_Type
3755 or else Rep_Item_Too_Early (Rectype, N)
3759 Rectype := Underlying_Type (Rectype);
3762 -- First some basic error checks
3764 if not Is_Record_Type (Rectype) then
3766 ("record type required, found}", Ident, First_Subtype (Rectype));
3769 elsif Scope (Rectype) /= Current_Scope then
3770 Error_Msg_N ("type must be declared in this scope", N);
3773 elsif not Is_First_Subtype (Rectype) then
3774 Error_Msg_N ("cannot give record rep clause for subtype", N);
3777 elsif Has_Record_Rep_Clause (Rectype) then
3778 Error_Msg_N ("duplicate record rep clause ignored", N);
3781 elsif Rep_Item_Too_Late (Rectype, N) then
3785 if Present (Mod_Clause (N)) then
3787 Loc : constant Source_Ptr := Sloc (N);
3788 M : constant Node_Id := Mod_Clause (N);
3789 P : constant List_Id := Pragmas_Before (M);
3793 pragma Warnings (Off, Mod_Val);
3796 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3798 if Warn_On_Obsolescent_Feature then
3800 ("mod clause is an obsolescent feature (RM J.8)?", N);
3802 ("\use alignment attribute definition clause instead?", N);
3809 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3810 -- the Mod clause into an alignment clause anyway, so that the
3811 -- back-end can compute and back-annotate properly the size and
3812 -- alignment of types that may include this record.
3814 -- This seems dubious, this destroys the source tree in a manner
3815 -- not detectable by ASIS ???
3817 if Operating_Mode = Check_Semantics
3821 Make_Attribute_Definition_Clause (Loc,
3822 Name => New_Reference_To (Base_Type (Rectype), Loc),
3823 Chars => Name_Alignment,
3824 Expression => Relocate_Node (Expression (M)));
3826 Set_From_At_Mod (AtM_Nod);
3827 Insert_After (N, AtM_Nod);
3828 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3829 Set_Mod_Clause (N, Empty);
3832 -- Get the alignment value to perform error checking
3834 Mod_Val := Get_Alignment_Value (Expression (M));
3839 -- For untagged types, clear any existing component clauses for the
3840 -- type. If the type is derived, this is what allows us to override
3841 -- a rep clause for the parent. For type extensions, the representation
3842 -- of the inherited components is inherited, so we want to keep previous
3843 -- component clauses for completeness.
3845 if not Is_Tagged_Type (Rectype) then
3846 Comp := First_Component_Or_Discriminant (Rectype);
3847 while Present (Comp) loop
3848 Set_Component_Clause (Comp, Empty);
3849 Next_Component_Or_Discriminant (Comp);
3853 -- All done if no component clauses
3855 CC := First (Component_Clauses (N));
3861 -- A representation like this applies to the base type
3863 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3864 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3865 Set_Has_Specified_Layout (Base_Type (Rectype));
3867 -- Process the component clauses
3869 while Present (CC) loop
3873 if Nkind (CC) = N_Pragma then
3876 -- The only pragma of interest is Complete_Representation
3878 if Pragma_Name (CC) = Name_Complete_Representation then
3882 -- Processing for real component clause
3885 Posit := Static_Integer (Position (CC));
3886 Fbit := Static_Integer (First_Bit (CC));
3887 Lbit := Static_Integer (Last_Bit (CC));
3890 and then Fbit /= No_Uint
3891 and then Lbit /= No_Uint
3895 ("position cannot be negative", Position (CC));
3899 ("first bit cannot be negative", First_Bit (CC));
3901 -- The Last_Bit specified in a component clause must not be
3902 -- less than the First_Bit minus one (RM-13.5.1(10)).
3904 elsif Lbit < Fbit - 1 then
3906 ("last bit cannot be less than first bit minus one",
3909 -- Values look OK, so find the corresponding record component
3910 -- Even though the syntax allows an attribute reference for
3911 -- implementation-defined components, GNAT does not allow the
3912 -- tag to get an explicit position.
3914 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
3915 if Attribute_Name (Component_Name (CC)) = Name_Tag then
3916 Error_Msg_N ("position of tag cannot be specified", CC);
3918 Error_Msg_N ("illegal component name", CC);
3922 Comp := First_Entity (Rectype);
3923 while Present (Comp) loop
3924 exit when Chars (Comp) = Chars (Component_Name (CC));
3930 -- Maybe component of base type that is absent from
3931 -- statically constrained first subtype.
3933 Comp := First_Entity (Base_Type (Rectype));
3934 while Present (Comp) loop
3935 exit when Chars (Comp) = Chars (Component_Name (CC));
3942 ("component clause is for non-existent field", CC);
3944 -- Ada 2012 (AI05-0026): Any name that denotes a
3945 -- discriminant of an object of an unchecked union type
3946 -- shall not occur within a record_representation_clause.
3948 -- The general restriction of using record rep clauses on
3949 -- Unchecked_Union types has now been lifted. Since it is
3950 -- possible to introduce a record rep clause which mentions
3951 -- the discriminant of an Unchecked_Union in non-Ada 2012
3952 -- code, this check is applied to all versions of the
3955 elsif Ekind (Comp) = E_Discriminant
3956 and then Is_Unchecked_Union (Rectype)
3959 ("cannot reference discriminant of Unchecked_Union",
3960 Component_Name (CC));
3962 elsif Present (Component_Clause (Comp)) then
3964 -- Diagnose duplicate rep clause, or check consistency
3965 -- if this is an inherited component. In a double fault,
3966 -- there may be a duplicate inconsistent clause for an
3967 -- inherited component.
3969 if Scope (Original_Record_Component (Comp)) = Rectype
3970 or else Parent (Component_Clause (Comp)) = N
3972 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
3973 Error_Msg_N ("component clause previously given#", CC);
3977 Rep1 : constant Node_Id := Component_Clause (Comp);
3979 if Intval (Position (Rep1)) /=
3980 Intval (Position (CC))
3981 or else Intval (First_Bit (Rep1)) /=
3982 Intval (First_Bit (CC))
3983 or else Intval (Last_Bit (Rep1)) /=
3984 Intval (Last_Bit (CC))
3986 Error_Msg_N ("component clause inconsistent "
3987 & "with representation of ancestor", CC);
3988 elsif Warn_On_Redundant_Constructs then
3989 Error_Msg_N ("?redundant component clause "
3990 & "for inherited component!", CC);
3995 -- Normal case where this is the first component clause we
3996 -- have seen for this entity, so set it up properly.
3999 -- Make reference for field in record rep clause and set
4000 -- appropriate entity field in the field identifier.
4003 (Comp, Component_Name (CC), Set_Ref => False);
4004 Set_Entity (Component_Name (CC), Comp);
4006 -- Update Fbit and Lbit to the actual bit number
4008 Fbit := Fbit + UI_From_Int (SSU) * Posit;
4009 Lbit := Lbit + UI_From_Int (SSU) * Posit;
4011 if Has_Size_Clause (Rectype)
4012 and then RM_Size (Rectype) <= Lbit
4015 ("bit number out of range of specified size",
4018 Set_Component_Clause (Comp, CC);
4019 Set_Component_Bit_Offset (Comp, Fbit);
4020 Set_Esize (Comp, 1 + (Lbit - Fbit));
4021 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
4022 Set_Normalized_Position (Comp, Fbit / SSU);
4024 if Warn_On_Overridden_Size
4025 and then Has_Size_Clause (Etype (Comp))
4026 and then RM_Size (Etype (Comp)) /= Esize (Comp)
4029 ("?component size overrides size clause for&",
4030 Component_Name (CC), Etype (Comp));
4033 -- This information is also set in the corresponding
4034 -- component of the base type, found by accessing the
4035 -- Original_Record_Component link if it is present.
4037 Ocomp := Original_Record_Component (Comp);
4044 (Component_Name (CC),
4050 (Comp, First_Node (CC), "component clause", Biased);
4052 if Present (Ocomp) then
4053 Set_Component_Clause (Ocomp, CC);
4054 Set_Component_Bit_Offset (Ocomp, Fbit);
4055 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
4056 Set_Normalized_Position (Ocomp, Fbit / SSU);
4057 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
4059 Set_Normalized_Position_Max
4060 (Ocomp, Normalized_Position (Ocomp));
4062 -- Note: we don't use Set_Biased here, because we
4063 -- already gave a warning above if needed, and we
4064 -- would get a duplicate for the same name here.
4066 Set_Has_Biased_Representation
4067 (Ocomp, Has_Biased_Representation (Comp));
4070 if Esize (Comp) < 0 then
4071 Error_Msg_N ("component size is negative", CC);
4082 -- Check missing components if Complete_Representation pragma appeared
4084 if Present (CR_Pragma) then
4085 Comp := First_Component_Or_Discriminant (Rectype);
4086 while Present (Comp) loop
4087 if No (Component_Clause (Comp)) then
4089 ("missing component clause for &", CR_Pragma, Comp);
4092 Next_Component_Or_Discriminant (Comp);
4095 -- If no Complete_Representation pragma, warn if missing components
4097 elsif Warn_On_Unrepped_Components then
4099 Num_Repped_Components : Nat := 0;
4100 Num_Unrepped_Components : Nat := 0;
4103 -- First count number of repped and unrepped components
4105 Comp := First_Component_Or_Discriminant (Rectype);
4106 while Present (Comp) loop
4107 if Present (Component_Clause (Comp)) then
4108 Num_Repped_Components := Num_Repped_Components + 1;
4110 Num_Unrepped_Components := Num_Unrepped_Components + 1;
4113 Next_Component_Or_Discriminant (Comp);
4116 -- We are only interested in the case where there is at least one
4117 -- unrepped component, and at least half the components have rep
4118 -- clauses. We figure that if less than half have them, then the
4119 -- partial rep clause is really intentional. If the component
4120 -- type has no underlying type set at this point (as for a generic
4121 -- formal type), we don't know enough to give a warning on the
4124 if Num_Unrepped_Components > 0
4125 and then Num_Unrepped_Components < Num_Repped_Components
4127 Comp := First_Component_Or_Discriminant (Rectype);
4128 while Present (Comp) loop
4129 if No (Component_Clause (Comp))
4130 and then Comes_From_Source (Comp)
4131 and then Present (Underlying_Type (Etype (Comp)))
4132 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
4133 or else Size_Known_At_Compile_Time
4134 (Underlying_Type (Etype (Comp))))
4135 and then not Has_Warnings_Off (Rectype)
4137 Error_Msg_Sloc := Sloc (Comp);
4139 ("?no component clause given for & declared #",
4143 Next_Component_Or_Discriminant (Comp);
4148 end Analyze_Record_Representation_Clause;
4150 -------------------------------
4151 -- Build_Invariant_Procedure --
4152 -------------------------------
4154 -- The procedure that is constructed here has the form
4156 -- procedure typInvariant (Ixxx : typ) is
4158 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4159 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4161 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
4163 -- end typInvariant;
4165 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
4166 Loc : constant Source_Ptr := Sloc (Typ);
4173 Visible_Decls : constant List_Id := Visible_Declarations (N);
4174 Private_Decls : constant List_Id := Private_Declarations (N);
4176 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
4177 -- Appends statements to Stmts for any invariants in the rep item chain
4178 -- of the given type. If Inherit is False, then we only process entries
4179 -- on the chain for the type Typ. If Inherit is True, then we ignore any
4180 -- Invariant aspects, but we process all Invariant'Class aspects, adding
4181 -- "inherited" to the exception message and generating an informational
4182 -- message about the inheritance of an invariant.
4184 Object_Name : constant Name_Id := New_Internal_Name ('I');
4185 -- Name for argument of invariant procedure
4187 Object_Entity : constant Node_Id :=
4188 Make_Defining_Identifier (Loc, Object_Name);
4189 -- The procedure declaration entity for the argument
4191 --------------------
4192 -- Add_Invariants --
4193 --------------------
4195 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
4205 procedure Replace_Type_Reference (N : Node_Id);
4206 -- Replace a single occurrence N of the subtype name with a reference
4207 -- to the formal of the predicate function. N can be an identifier
4208 -- referencing the subtype, or a selected component, representing an
4209 -- appropriately qualified occurrence of the subtype name.
4211 procedure Replace_Type_References is
4212 new Replace_Type_References_Generic (Replace_Type_Reference);
4213 -- Traverse an expression replacing all occurrences of the subtype
4214 -- name with appropriate references to the object that is the formal
4215 -- parameter of the predicate function. Note that we must ensure
4216 -- that the type and entity information is properly set in the
4217 -- replacement node, since we will do a Preanalyze call of this
4218 -- expression without proper visibility of the procedure argument.
4220 ----------------------------
4221 -- Replace_Type_Reference --
4222 ----------------------------
4224 procedure Replace_Type_Reference (N : Node_Id) is
4226 -- Invariant'Class, replace with T'Class (obj)
4228 if Class_Present (Ritem) then
4230 Make_Type_Conversion (Loc,
4232 Make_Attribute_Reference (Loc,
4233 Prefix => New_Occurrence_Of (T, Loc),
4234 Attribute_Name => Name_Class),
4235 Expression => Make_Identifier (Loc, Object_Name)));
4237 Set_Entity (Expression (N), Object_Entity);
4238 Set_Etype (Expression (N), Typ);
4240 -- Invariant, replace with obj
4243 Rewrite (N, Make_Identifier (Loc, Object_Name));
4244 Set_Entity (N, Object_Entity);
4247 end Replace_Type_Reference;
4249 -- Start of processing for Add_Invariants
4252 Ritem := First_Rep_Item (T);
4253 while Present (Ritem) loop
4254 if Nkind (Ritem) = N_Pragma
4255 and then Pragma_Name (Ritem) = Name_Invariant
4257 Arg1 := First (Pragma_Argument_Associations (Ritem));
4258 Arg2 := Next (Arg1);
4259 Arg3 := Next (Arg2);
4261 Arg1 := Get_Pragma_Arg (Arg1);
4262 Arg2 := Get_Pragma_Arg (Arg2);
4264 -- For Inherit case, ignore Invariant, process only Class case
4267 if not Class_Present (Ritem) then
4271 -- For Inherit false, process only item for right type
4274 if Entity (Arg1) /= Typ then
4280 Stmts := Empty_List;
4283 Exp := New_Copy_Tree (Arg2);
4286 -- We need to replace any occurrences of the name of the type
4287 -- with references to the object, converted to type'Class in
4288 -- the case of Invariant'Class aspects.
4290 Replace_Type_References (Exp, Chars (T));
4292 -- If this invariant comes from an aspect, find the aspect
4293 -- specification, and replace the saved expression because
4294 -- we need the subtype references replaced for the calls to
4295 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4296 -- and Check_Aspect_At_End_Of_Declarations.
4298 if From_Aspect_Specification (Ritem) then
4303 -- Loop to find corresponding aspect, note that this
4304 -- must be present given the pragma is marked delayed.
4306 Aitem := Next_Rep_Item (Ritem);
4307 while Present (Aitem) loop
4308 if Nkind (Aitem) = N_Aspect_Specification
4309 and then Aspect_Rep_Item (Aitem) = Ritem
4312 (Identifier (Aitem), New_Copy_Tree (Exp));
4316 Aitem := Next_Rep_Item (Aitem);
4321 -- Now we need to preanalyze the expression to properly capture
4322 -- the visibility in the visible part. The expression will not
4323 -- be analyzed for real until the body is analyzed, but that is
4324 -- at the end of the private part and has the wrong visibility.
4326 Set_Parent (Exp, N);
4327 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
4329 -- Build first two arguments for Check pragma
4332 Make_Pragma_Argument_Association (Loc,
4333 Expression => Make_Identifier (Loc, Name_Invariant)),
4334 Make_Pragma_Argument_Association (Loc, Expression => Exp));
4336 -- Add message if present in Invariant pragma
4338 if Present (Arg3) then
4339 Str := Strval (Get_Pragma_Arg (Arg3));
4341 -- If inherited case, and message starts "failed invariant",
4342 -- change it to be "failed inherited invariant".
4345 String_To_Name_Buffer (Str);
4347 if Name_Buffer (1 .. 16) = "failed invariant" then
4348 Insert_Str_In_Name_Buffer ("inherited ", 8);
4349 Str := String_From_Name_Buffer;
4354 Make_Pragma_Argument_Association (Loc,
4355 Expression => Make_String_Literal (Loc, Str)));
4358 -- Add Check pragma to list of statements
4362 Pragma_Identifier =>
4363 Make_Identifier (Loc, Name_Check),
4364 Pragma_Argument_Associations => Assoc));
4366 -- If Inherited case and option enabled, output info msg. Note
4367 -- that we know this is a case of Invariant'Class.
4369 if Inherit and Opt.List_Inherited_Aspects then
4370 Error_Msg_Sloc := Sloc (Ritem);
4372 ("?info: & inherits `Invariant''Class` aspect from #",
4378 Next_Rep_Item (Ritem);
4382 -- Start of processing for Build_Invariant_Procedure
4388 Set_Etype (Object_Entity, Typ);
4390 -- Add invariants for the current type
4392 Add_Invariants (Typ, Inherit => False);
4394 -- Add invariants for parent types
4397 Current_Typ : Entity_Id;
4398 Parent_Typ : Entity_Id;
4403 Parent_Typ := Etype (Current_Typ);
4405 if Is_Private_Type (Parent_Typ)
4406 and then Present (Full_View (Base_Type (Parent_Typ)))
4408 Parent_Typ := Full_View (Base_Type (Parent_Typ));
4411 exit when Parent_Typ = Current_Typ;
4413 Current_Typ := Parent_Typ;
4414 Add_Invariants (Current_Typ, Inherit => True);
4418 -- Build the procedure if we generated at least one Check pragma
4420 if Stmts /= No_List then
4422 -- Build procedure declaration
4425 Make_Defining_Identifier (Loc,
4426 Chars => New_External_Name (Chars (Typ), "Invariant"));
4427 Set_Has_Invariants (SId);
4428 Set_Invariant_Procedure (Typ, SId);
4431 Make_Procedure_Specification (Loc,
4432 Defining_Unit_Name => SId,
4433 Parameter_Specifications => New_List (
4434 Make_Parameter_Specification (Loc,
4435 Defining_Identifier => Object_Entity,
4436 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4438 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4440 -- Build procedure body
4443 Make_Defining_Identifier (Loc,
4444 Chars => New_External_Name (Chars (Typ), "Invariant"));
4447 Make_Procedure_Specification (Loc,
4448 Defining_Unit_Name => SId,
4449 Parameter_Specifications => New_List (
4450 Make_Parameter_Specification (Loc,
4451 Defining_Identifier =>
4452 Make_Defining_Identifier (Loc, Object_Name),
4453 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4456 Make_Subprogram_Body (Loc,
4457 Specification => Spec,
4458 Declarations => Empty_List,
4459 Handled_Statement_Sequence =>
4460 Make_Handled_Sequence_Of_Statements (Loc,
4461 Statements => Stmts));
4463 -- Insert procedure declaration and spec at the appropriate points.
4464 -- Skip this if there are no private declarations (that's an error
4465 -- that will be diagnosed elsewhere, and there is no point in having
4466 -- an invariant procedure set if the full declaration is missing).
4468 if Present (Private_Decls) then
4470 -- The spec goes at the end of visible declarations, but they have
4471 -- already been analyzed, so we need to explicitly do the analyze.
4473 Append_To (Visible_Decls, PDecl);
4476 -- The body goes at the end of the private declarations, which we
4477 -- have not analyzed yet, so we do not need to perform an explicit
4478 -- analyze call. We skip this if there are no private declarations
4479 -- (this is an error that will be caught elsewhere);
4481 Append_To (Private_Decls, PBody);
4484 end Build_Invariant_Procedure;
4486 ------------------------------
4487 -- Build_Predicate_Function --
4488 ------------------------------
4490 -- The procedure that is constructed here has the form
4492 -- function typPredicate (Ixxx : typ) return Boolean is
4495 -- exp1 and then exp2 and then ...
4496 -- and then typ1Predicate (typ1 (Ixxx))
4497 -- and then typ2Predicate (typ2 (Ixxx))
4499 -- end typPredicate;
4501 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4502 -- this is the point at which these expressions get analyzed, providing the
4503 -- required delay, and typ1, typ2, are entities from which predicates are
4504 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4505 -- use this function even if checks are off, e.g. for membership tests.
4507 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4508 Loc : constant Source_Ptr := Sloc (Typ);
4515 -- This is the expression for the return statement in the function. It
4516 -- is build by connecting the component predicates with AND THEN.
4518 procedure Add_Call (T : Entity_Id);
4519 -- Includes a call to the predicate function for type T in Expr if T
4520 -- has predicates and Predicate_Function (T) is non-empty.
4522 procedure Add_Predicates;
4523 -- Appends expressions for any Predicate pragmas in the rep item chain
4524 -- Typ to Expr. Note that we look only at items for this exact entity.
4525 -- Inheritance of predicates for the parent type is done by calling the
4526 -- Predicate_Function of the parent type, using Add_Call above.
4528 Object_Name : constant Name_Id := New_Internal_Name ('I');
4529 -- Name for argument of Predicate procedure
4531 Object_Entity : constant Entity_Id :=
4532 Make_Defining_Identifier (Loc, Object_Name);
4533 -- The entity for the spec entity for the argument
4535 Dynamic_Predicate_Present : Boolean := False;
4536 -- Set True if a dynamic predicate is present, results in the entire
4537 -- predicate being considered dynamic even if it looks static
4539 Static_Predicate_Present : Node_Id := Empty;
4540 -- Set to N_Pragma node for a static predicate if one is encountered.
4546 procedure Add_Call (T : Entity_Id) is
4550 if Present (T) and then Present (Predicate_Function (T)) then
4551 Set_Has_Predicates (Typ);
4553 -- Build the call to the predicate function of T
4557 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4559 -- Add call to evolving expression, using AND THEN if needed
4566 Left_Opnd => Relocate_Node (Expr),
4570 -- Output info message on inheritance if required. Note we do not
4571 -- give this information for generic actual types, since it is
4572 -- unwelcome noise in that case in instantiations. We also
4573 -- generally suppress the message in instantiations, and also
4574 -- if it involves internal names.
4576 if Opt.List_Inherited_Aspects
4577 and then not Is_Generic_Actual_Type (Typ)
4578 and then Instantiation_Depth (Sloc (Typ)) = 0
4579 and then not Is_Internal_Name (Chars (T))
4580 and then not Is_Internal_Name (Chars (Typ))
4582 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4583 Error_Msg_Node_2 := T;
4584 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4589 --------------------
4590 -- Add_Predicates --
4591 --------------------
4593 procedure Add_Predicates is
4598 procedure Replace_Type_Reference (N : Node_Id);
4599 -- Replace a single occurrence N of the subtype name with a reference
4600 -- to the formal of the predicate function. N can be an identifier
4601 -- referencing the subtype, or a selected component, representing an
4602 -- appropriately qualified occurrence of the subtype name.
4604 procedure Replace_Type_References is
4605 new Replace_Type_References_Generic (Replace_Type_Reference);
4606 -- Traverse an expression changing every occurrence of an identifier
4607 -- whose name matches the name of the subtype with a reference to
4608 -- the formal parameter of the predicate function.
4610 ----------------------------
4611 -- Replace_Type_Reference --
4612 ----------------------------
4614 procedure Replace_Type_Reference (N : Node_Id) is
4616 Rewrite (N, Make_Identifier (Loc, Object_Name));
4617 Set_Entity (N, Object_Entity);
4619 end Replace_Type_Reference;
4621 -- Start of processing for Add_Predicates
4624 Ritem := First_Rep_Item (Typ);
4625 while Present (Ritem) loop
4626 if Nkind (Ritem) = N_Pragma
4627 and then Pragma_Name (Ritem) = Name_Predicate
4629 if From_Dynamic_Predicate (Ritem) then
4630 Dynamic_Predicate_Present := True;
4631 elsif From_Static_Predicate (Ritem) then
4632 Static_Predicate_Present := Ritem;
4635 -- Acquire arguments
4637 Arg1 := First (Pragma_Argument_Associations (Ritem));
4638 Arg2 := Next (Arg1);
4640 Arg1 := Get_Pragma_Arg (Arg1);
4641 Arg2 := Get_Pragma_Arg (Arg2);
4643 -- See if this predicate pragma is for the current type or for
4644 -- its full view. A predicate on a private completion is placed
4645 -- on the partial view beause this is the visible entity that
4648 if Entity (Arg1) = Typ
4649 or else Full_View (Entity (Arg1)) = Typ
4652 -- We have a match, this entry is for our subtype
4654 -- We need to replace any occurrences of the name of the
4655 -- type with references to the object.
4657 Replace_Type_References (Arg2, Chars (Typ));
4659 -- If this predicate comes from an aspect, find the aspect
4660 -- specification, and replace the saved expression because
4661 -- we need the subtype references replaced for the calls to
4662 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4663 -- and Check_Aspect_At_End_Of_Declarations.
4665 if From_Aspect_Specification (Ritem) then
4670 -- Loop to find corresponding aspect, note that this
4671 -- must be present given the pragma is marked delayed.
4673 Aitem := Next_Rep_Item (Ritem);
4675 if Nkind (Aitem) = N_Aspect_Specification
4676 and then Aspect_Rep_Item (Aitem) = Ritem
4679 (Identifier (Aitem), New_Copy_Tree (Arg2));
4683 Aitem := Next_Rep_Item (Aitem);
4688 -- Now we can add the expression
4691 Expr := Relocate_Node (Arg2);
4693 -- There already was a predicate, so add to it
4698 Left_Opnd => Relocate_Node (Expr),
4699 Right_Opnd => Relocate_Node (Arg2));
4704 Next_Rep_Item (Ritem);
4708 -- Start of processing for Build_Predicate_Function
4711 -- Initialize for construction of statement list
4715 -- Return if already built or if type does not have predicates
4717 if not Has_Predicates (Typ)
4718 or else Present (Predicate_Function (Typ))
4723 -- Add Predicates for the current type
4727 -- Add predicates for ancestor if present
4730 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4732 if Present (Atyp) then
4737 -- If we have predicates, build the function
4739 if Present (Expr) then
4741 -- Build function declaration
4743 pragma Assert (Has_Predicates (Typ));
4745 Make_Defining_Identifier (Loc,
4746 Chars => New_External_Name (Chars (Typ), "Predicate"));
4747 Set_Has_Predicates (SId);
4748 Set_Predicate_Function (Typ, SId);
4751 Make_Function_Specification (Loc,
4752 Defining_Unit_Name => SId,
4753 Parameter_Specifications => New_List (
4754 Make_Parameter_Specification (Loc,
4755 Defining_Identifier => Object_Entity,
4756 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4757 Result_Definition =>
4758 New_Occurrence_Of (Standard_Boolean, Loc));
4760 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4762 -- Build function body
4765 Make_Defining_Identifier (Loc,
4766 Chars => New_External_Name (Chars (Typ), "Predicate"));
4769 Make_Function_Specification (Loc,
4770 Defining_Unit_Name => SId,
4771 Parameter_Specifications => New_List (
4772 Make_Parameter_Specification (Loc,
4773 Defining_Identifier =>
4774 Make_Defining_Identifier (Loc, Object_Name),
4776 New_Occurrence_Of (Typ, Loc))),
4777 Result_Definition =>
4778 New_Occurrence_Of (Standard_Boolean, Loc));
4781 Make_Subprogram_Body (Loc,
4782 Specification => Spec,
4783 Declarations => Empty_List,
4784 Handled_Statement_Sequence =>
4785 Make_Handled_Sequence_Of_Statements (Loc,
4786 Statements => New_List (
4787 Make_Simple_Return_Statement (Loc,
4788 Expression => Expr))));
4790 -- Insert declaration before freeze node and body after
4792 Insert_Before_And_Analyze (N, FDecl);
4793 Insert_After_And_Analyze (N, FBody);
4795 -- Deal with static predicate case
4797 if Ekind_In (Typ, E_Enumeration_Subtype,
4798 E_Modular_Integer_Subtype,
4799 E_Signed_Integer_Subtype)
4800 and then Is_Static_Subtype (Typ)
4801 and then not Dynamic_Predicate_Present
4803 Build_Static_Predicate (Typ, Expr, Object_Name);
4805 if Present (Static_Predicate_Present)
4806 and No (Static_Predicate (Typ))
4809 ("expression does not have required form for "
4810 & "static predicate",
4811 Next (First (Pragma_Argument_Associations
4812 (Static_Predicate_Present))));
4816 end Build_Predicate_Function;
4818 ----------------------------
4819 -- Build_Static_Predicate --
4820 ----------------------------
4822 procedure Build_Static_Predicate
4827 Loc : constant Source_Ptr := Sloc (Expr);
4829 Non_Static : exception;
4830 -- Raised if something non-static is found
4832 Btyp : constant Entity_Id := Base_Type (Typ);
4834 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4835 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4836 -- Low bound and high bound value of base type of Typ
4838 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4839 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4840 -- Low bound and high bound values of static subtype Typ
4845 -- One entry in a Rlist value, a single REnt (range entry) value
4846 -- denotes one range from Lo to Hi. To represent a single value
4847 -- range Lo = Hi = value.
4849 type RList is array (Nat range <>) of REnt;
4850 -- A list of ranges. The ranges are sorted in increasing order,
4851 -- and are disjoint (there is a gap of at least one value between
4852 -- each range in the table). A value is in the set of ranges in
4853 -- Rlist if it lies within one of these ranges
4855 False_Range : constant RList :=
4856 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4857 -- An empty set of ranges represents a range list that can never be
4858 -- satisfied, since there are no ranges in which the value could lie,
4859 -- so it does not lie in any of them. False_Range is a canonical value
4860 -- for this empty set, but general processing should test for an Rlist
4861 -- with length zero (see Is_False predicate), since other null ranges
4862 -- may appear which must be treated as False.
4864 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4865 -- Range representing True, value must be in the base range
4867 function "and" (Left, Right : RList) return RList;
4868 -- And's together two range lists, returning a range list. This is
4869 -- a set intersection operation.
4871 function "or" (Left, Right : RList) return RList;
4872 -- Or's together two range lists, returning a range list. This is a
4873 -- set union operation.
4875 function "not" (Right : RList) return RList;
4876 -- Returns complement of a given range list, i.e. a range list
4877 -- representing all the values in TLo .. THi that are not in the
4878 -- input operand Right.
4880 function Build_Val (V : Uint) return Node_Id;
4881 -- Return an analyzed N_Identifier node referencing this value, suitable
4882 -- for use as an entry in the Static_Predicate list. This node is typed
4883 -- with the base type.
4885 function Build_Range (Lo, Hi : Uint) return Node_Id;
4886 -- Return an analyzed N_Range node referencing this range, suitable
4887 -- for use as an entry in the Static_Predicate list. This node is typed
4888 -- with the base type.
4890 function Get_RList (Exp : Node_Id) return RList;
4891 -- This is a recursive routine that converts the given expression into
4892 -- a list of ranges, suitable for use in building the static predicate.
4894 function Is_False (R : RList) return Boolean;
4895 pragma Inline (Is_False);
4896 -- Returns True if the given range list is empty, and thus represents
4897 -- a False list of ranges that can never be satisfied.
4899 function Is_True (R : RList) return Boolean;
4900 -- Returns True if R trivially represents the True predicate by having
4901 -- a single range from BLo to BHi.
4903 function Is_Type_Ref (N : Node_Id) return Boolean;
4904 pragma Inline (Is_Type_Ref);
4905 -- Returns if True if N is a reference to the type for the predicate in
4906 -- the expression (i.e. if it is an identifier whose Chars field matches
4907 -- the Nam given in the call).
4909 function Lo_Val (N : Node_Id) return Uint;
4910 -- Given static expression or static range from a Static_Predicate list,
4911 -- gets expression value or low bound of range.
4913 function Hi_Val (N : Node_Id) return Uint;
4914 -- Given static expression or static range from a Static_Predicate list,
4915 -- gets expression value of high bound of range.
4917 function Membership_Entry (N : Node_Id) return RList;
4918 -- Given a single membership entry (range, value, or subtype), returns
4919 -- the corresponding range list. Raises Static_Error if not static.
4921 function Membership_Entries (N : Node_Id) return RList;
4922 -- Given an element on an alternatives list of a membership operation,
4923 -- returns the range list corresponding to this entry and all following
4924 -- entries (i.e. returns the "or" of this list of values).
4926 function Stat_Pred (Typ : Entity_Id) return RList;
4927 -- Given a type, if it has a static predicate, then return the predicate
4928 -- as a range list, otherwise raise Non_Static.
4934 function "and" (Left, Right : RList) return RList is
4936 -- First range of result
4938 SLeft : Nat := Left'First;
4939 -- Start of rest of left entries
4941 SRight : Nat := Right'First;
4942 -- Start of rest of right entries
4945 -- If either range is True, return the other
4947 if Is_True (Left) then
4949 elsif Is_True (Right) then
4953 -- If either range is False, return False
4955 if Is_False (Left) or else Is_False (Right) then
4959 -- Loop to remove entries at start that are disjoint, and thus
4960 -- just get discarded from the result entirely.
4963 -- If no operands left in either operand, result is false
4965 if SLeft > Left'Last or else SRight > Right'Last then
4968 -- Discard first left operand entry if disjoint with right
4970 elsif Left (SLeft).Hi < Right (SRight).Lo then
4973 -- Discard first right operand entry if disjoint with left
4975 elsif Right (SRight).Hi < Left (SLeft).Lo then
4976 SRight := SRight + 1;
4978 -- Otherwise we have an overlapping entry
4985 -- Now we have two non-null operands, and first entries overlap.
4986 -- The first entry in the result will be the overlapping part of
4987 -- these two entries.
4989 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
4990 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
4992 -- Now we can remove the entry that ended at a lower value, since
4993 -- its contribution is entirely contained in Fent.
4995 if Left (SLeft).Hi <= Right (SRight).Hi then
4998 SRight := SRight + 1;
5001 -- Compute result by concatenating this first entry with the "and"
5002 -- of the remaining parts of the left and right operands. Note that
5003 -- if either of these is empty, "and" will yield empty, so that we
5004 -- will end up with just Fent, which is what we want in that case.
5007 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
5014 function "not" (Right : RList) return RList is
5016 -- Return True if False range
5018 if Is_False (Right) then
5022 -- Return False if True range
5024 if Is_True (Right) then
5028 -- Here if not trivial case
5031 Result : RList (1 .. Right'Length + 1);
5032 -- May need one more entry for gap at beginning and end
5035 -- Number of entries stored in Result
5040 if Right (Right'First).Lo > TLo then
5042 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
5045 -- Gaps between ranges
5047 for J in Right'First .. Right'Last - 1 loop
5050 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
5055 if Right (Right'Last).Hi < THi then
5057 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
5060 return Result (1 .. Count);
5068 function "or" (Left, Right : RList) return RList is
5070 -- First range of result
5072 SLeft : Nat := Left'First;
5073 -- Start of rest of left entries
5075 SRight : Nat := Right'First;
5076 -- Start of rest of right entries
5079 -- If either range is True, return True
5081 if Is_True (Left) or else Is_True (Right) then
5085 -- If either range is False (empty), return the other
5087 if Is_False (Left) then
5089 elsif Is_False (Right) then
5093 -- Initialize result first entry from left or right operand
5094 -- depending on which starts with the lower range.
5096 if Left (SLeft).Lo < Right (SRight).Lo then
5097 FEnt := Left (SLeft);
5100 FEnt := Right (SRight);
5101 SRight := SRight + 1;
5104 -- This loop eats ranges from left and right operands that
5105 -- are contiguous with the first range we are gathering.
5108 -- Eat first entry in left operand if contiguous or
5109 -- overlapped by gathered first operand of result.
5111 if SLeft <= Left'Last
5112 and then Left (SLeft).Lo <= FEnt.Hi + 1
5114 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
5117 -- Eat first entry in right operand if contiguous or
5118 -- overlapped by gathered right operand of result.
5120 elsif SRight <= Right'Last
5121 and then Right (SRight).Lo <= FEnt.Hi + 1
5123 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
5124 SRight := SRight + 1;
5126 -- All done if no more entries to eat!
5133 -- Obtain result as the first entry we just computed, concatenated
5134 -- to the "or" of the remaining results (if one operand is empty,
5135 -- this will just concatenate with the other
5138 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
5145 function Build_Range (Lo, Hi : Uint) return Node_Id is
5149 return Build_Val (Hi);
5153 Low_Bound => Build_Val (Lo),
5154 High_Bound => Build_Val (Hi));
5155 Set_Etype (Result, Btyp);
5156 Set_Analyzed (Result);
5165 function Build_Val (V : Uint) return Node_Id is
5169 if Is_Enumeration_Type (Typ) then
5170 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
5172 Result := Make_Integer_Literal (Loc, V);
5175 Set_Etype (Result, Btyp);
5176 Set_Is_Static_Expression (Result);
5177 Set_Analyzed (Result);
5185 function Get_RList (Exp : Node_Id) return RList is
5190 -- Static expression can only be true or false
5192 if Is_OK_Static_Expression (Exp) then
5196 if Expr_Value (Exp) = 0 then
5203 -- Otherwise test node type
5211 when N_Op_And | N_And_Then =>
5212 return Get_RList (Left_Opnd (Exp))
5214 Get_RList (Right_Opnd (Exp));
5218 when N_Op_Or | N_Or_Else =>
5219 return Get_RList (Left_Opnd (Exp))
5221 Get_RList (Right_Opnd (Exp));
5226 return not Get_RList (Right_Opnd (Exp));
5228 -- Comparisons of type with static value
5230 when N_Op_Compare =>
5231 -- Type is left operand
5233 if Is_Type_Ref (Left_Opnd (Exp))
5234 and then Is_OK_Static_Expression (Right_Opnd (Exp))
5236 Val := Expr_Value (Right_Opnd (Exp));
5238 -- Typ is right operand
5240 elsif Is_Type_Ref (Right_Opnd (Exp))
5241 and then Is_OK_Static_Expression (Left_Opnd (Exp))
5243 Val := Expr_Value (Left_Opnd (Exp));
5245 -- Invert sense of comparison
5248 when N_Op_Gt => Op := N_Op_Lt;
5249 when N_Op_Lt => Op := N_Op_Gt;
5250 when N_Op_Ge => Op := N_Op_Le;
5251 when N_Op_Le => Op := N_Op_Ge;
5252 when others => null;
5255 -- Other cases are non-static
5261 -- Construct range according to comparison operation
5265 return RList'(1 => REnt'(Val, Val));
5268 return RList'(1 => REnt'(Val, BHi));
5271 return RList'(1 => REnt'(Val + 1, BHi));
5274 return RList'(1 => REnt'(BLo, Val));
5277 return RList'(1 => REnt'(BLo, Val - 1));
5280 return RList'(REnt'(BLo, Val - 1),
5281 REnt'(Val + 1, BHi));
5284 raise Program_Error;
5290 if not Is_Type_Ref (Left_Opnd (Exp)) then
5294 if Present (Right_Opnd (Exp)) then
5295 return Membership_Entry (Right_Opnd (Exp));
5297 return Membership_Entries (First (Alternatives (Exp)));
5300 -- Negative membership (NOT IN)
5303 if not Is_Type_Ref (Left_Opnd (Exp)) then
5307 if Present (Right_Opnd (Exp)) then
5308 return not Membership_Entry (Right_Opnd (Exp));
5310 return not Membership_Entries (First (Alternatives (Exp)));
5313 -- Function call, may be call to static predicate
5315 when N_Function_Call =>
5316 if Is_Entity_Name (Name (Exp)) then
5318 Ent : constant Entity_Id := Entity (Name (Exp));
5320 if Has_Predicates (Ent) then
5321 return Stat_Pred (Etype (First_Formal (Ent)));
5326 -- Other function call cases are non-static
5330 -- Qualified expression, dig out the expression
5332 when N_Qualified_Expression =>
5333 return Get_RList (Expression (Exp));
5338 return (Get_RList (Left_Opnd (Exp))
5339 and not Get_RList (Right_Opnd (Exp)))
5340 or (Get_RList (Right_Opnd (Exp))
5341 and not Get_RList (Left_Opnd (Exp)));
5343 -- Any other node type is non-static
5354 function Hi_Val (N : Node_Id) return Uint is
5356 if Is_Static_Expression (N) then
5357 return Expr_Value (N);
5359 pragma Assert (Nkind (N) = N_Range);
5360 return Expr_Value (High_Bound (N));
5368 function Is_False (R : RList) return Boolean is
5370 return R'Length = 0;
5377 function Is_True (R : RList) return Boolean is
5380 and then R (R'First).Lo = BLo
5381 and then R (R'First).Hi = BHi;
5388 function Is_Type_Ref (N : Node_Id) return Boolean is
5390 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
5397 function Lo_Val (N : Node_Id) return Uint is
5399 if Is_Static_Expression (N) then
5400 return Expr_Value (N);
5402 pragma Assert (Nkind (N) = N_Range);
5403 return Expr_Value (Low_Bound (N));
5407 ------------------------
5408 -- Membership_Entries --
5409 ------------------------
5411 function Membership_Entries (N : Node_Id) return RList is
5413 if No (Next (N)) then
5414 return Membership_Entry (N);
5416 return Membership_Entry (N) or Membership_Entries (Next (N));
5418 end Membership_Entries;
5420 ----------------------
5421 -- Membership_Entry --
5422 ----------------------
5424 function Membership_Entry (N : Node_Id) return RList is
5432 if Nkind (N) = N_Range then
5433 if not Is_Static_Expression (Low_Bound (N))
5435 not Is_Static_Expression (High_Bound (N))
5439 SLo := Expr_Value (Low_Bound (N));
5440 SHi := Expr_Value (High_Bound (N));
5441 return RList'(1 => REnt'(SLo, SHi));
5444 -- Static expression case
5446 elsif Is_Static_Expression (N) then
5447 Val := Expr_Value (N);
5448 return RList'(1 => REnt'(Val, Val));
5450 -- Identifier (other than static expression) case
5452 else pragma Assert (Nkind (N) = N_Identifier);
5456 if Is_Type (Entity (N)) then
5458 -- If type has predicates, process them
5460 if Has_Predicates (Entity (N)) then
5461 return Stat_Pred (Entity (N));
5463 -- For static subtype without predicates, get range
5465 elsif Is_Static_Subtype (Entity (N)) then
5466 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
5467 SHi := Expr_Value (Type_High_Bound (Entity (N)));
5468 return RList'(1 => REnt'(SLo, SHi));
5470 -- Any other type makes us non-static
5476 -- Any other kind of identifier in predicate (e.g. a non-static
5477 -- expression value) means this is not a static predicate.
5483 end Membership_Entry;
5489 function Stat_Pred (Typ : Entity_Id) return RList is
5491 -- Not static if type does not have static predicates
5493 if not Has_Predicates (Typ)
5494 or else No (Static_Predicate (Typ))
5499 -- Otherwise we convert the predicate list to a range list
5502 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5506 P := First (Static_Predicate (Typ));
5507 for J in Result'Range loop
5508 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5516 -- Start of processing for Build_Static_Predicate
5519 -- Now analyze the expression to see if it is a static predicate
5522 Ranges : constant RList := Get_RList (Expr);
5523 -- Range list from expression if it is static
5528 -- Convert range list into a form for the static predicate. In the
5529 -- Ranges array, we just have raw ranges, these must be converted
5530 -- to properly typed and analyzed static expressions or range nodes.
5532 -- Note: here we limit ranges to the ranges of the subtype, so that
5533 -- a predicate is always false for values outside the subtype. That
5534 -- seems fine, such values are invalid anyway, and considering them
5535 -- to fail the predicate seems allowed and friendly, and furthermore
5536 -- simplifies processing for case statements and loops.
5540 for J in Ranges'Range loop
5542 Lo : Uint := Ranges (J).Lo;
5543 Hi : Uint := Ranges (J).Hi;
5546 -- Ignore completely out of range entry
5548 if Hi < TLo or else Lo > THi then
5551 -- Otherwise process entry
5554 -- Adjust out of range value to subtype range
5564 -- Convert range into required form
5567 Append_To (Plist, Build_Val (Lo));
5569 Append_To (Plist, Build_Range (Lo, Hi));
5575 -- Processing was successful and all entries were static, so now we
5576 -- can store the result as the predicate list.
5578 Set_Static_Predicate (Typ, Plist);
5580 -- The processing for static predicates put the expression into
5581 -- canonical form as a series of ranges. It also eliminated
5582 -- duplicates and collapsed and combined ranges. We might as well
5583 -- replace the alternatives list of the right operand of the
5584 -- membership test with the static predicate list, which will
5585 -- usually be more efficient.
5588 New_Alts : constant List_Id := New_List;
5593 Old_Node := First (Plist);
5594 while Present (Old_Node) loop
5595 New_Node := New_Copy (Old_Node);
5597 if Nkind (New_Node) = N_Range then
5598 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5599 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5602 Append_To (New_Alts, New_Node);
5606 -- If empty list, replace by False
5608 if Is_Empty_List (New_Alts) then
5609 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5611 -- Else replace by set membership test
5616 Left_Opnd => Make_Identifier (Loc, Nam),
5617 Right_Opnd => Empty,
5618 Alternatives => New_Alts));
5620 -- Resolve new expression in function context
5622 Install_Formals (Predicate_Function (Typ));
5623 Push_Scope (Predicate_Function (Typ));
5624 Analyze_And_Resolve (Expr, Standard_Boolean);
5630 -- If non-static, return doing nothing
5635 end Build_Static_Predicate;
5637 -----------------------------------------
5638 -- Check_Aspect_At_End_Of_Declarations --
5639 -----------------------------------------
5641 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5642 Ent : constant Entity_Id := Entity (ASN);
5643 Ident : constant Node_Id := Identifier (ASN);
5645 Freeze_Expr : constant Node_Id := Expression (ASN);
5646 -- Expression from call to Check_Aspect_At_Freeze_Point
5648 End_Decl_Expr : constant Node_Id := Entity (Ident);
5649 -- Expression to be analyzed at end of declarations
5651 T : constant Entity_Id := Etype (Freeze_Expr);
5652 -- Type required for preanalyze call
5654 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5657 -- Set False if error
5659 -- On entry to this procedure, Entity (Ident) contains a copy of the
5660 -- original expression from the aspect, saved for this purpose, and
5661 -- but Expression (Ident) is a preanalyzed copy of the expression,
5662 -- preanalyzed just after the freeze point.
5665 -- Case of stream attributes, just have to compare entities
5667 if A_Id = Aspect_Input or else
5668 A_Id = Aspect_Output or else
5669 A_Id = Aspect_Read or else
5672 Analyze (End_Decl_Expr);
5673 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5675 elsif A_Id = Aspect_Variable_Indexing or else
5676 A_Id = Aspect_Constant_Indexing or else
5677 A_Id = Aspect_Default_Iterator or else
5678 A_Id = Aspect_Iterator_Element
5680 Analyze (End_Decl_Expr);
5681 Analyze (Aspect_Rep_Item (ASN));
5683 -- If the end of declarations comes before any other freeze
5684 -- point, the Freeze_Expr is not analyzed: no check needed.
5687 Analyzed (Freeze_Expr)
5688 and then not In_Instance
5689 and then Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5694 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5695 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5698 -- Output error message if error
5702 ("visibility of aspect for& changes after freeze point",
5705 ("?info: & is frozen here, aspects evaluated at this point",
5706 Freeze_Node (Ent), Ent);
5708 end Check_Aspect_At_End_Of_Declarations;
5710 ----------------------------------
5711 -- Check_Aspect_At_Freeze_Point --
5712 ----------------------------------
5714 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5715 Ident : constant Node_Id := Identifier (ASN);
5716 -- Identifier (use Entity field to save expression)
5719 -- Type required for preanalyze call
5721 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5724 -- On entry to this procedure, Entity (Ident) contains a copy of the
5725 -- original expression from the aspect, saved for this purpose.
5727 -- On exit from this procedure Entity (Ident) is unchanged, still
5728 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5729 -- of the expression, preanalyzed just after the freeze point.
5731 -- Make a copy of the expression to be preanalyed
5733 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5735 -- Find type for preanalyze call
5739 -- No_Aspect should be impossible
5742 raise Program_Error;
5744 -- Library unit aspects should be impossible (never delayed)
5746 when Library_Unit_Aspects =>
5747 raise Program_Error;
5749 -- Aspects taking an optional boolean argument. Should be impossible
5750 -- since these are never delayed.
5752 when Boolean_Aspects =>
5753 raise Program_Error;
5755 -- Test_Case aspect applies to entries and subprograms, hence should
5756 -- never be delayed.
5758 when Aspect_Test_Case =>
5759 raise Program_Error;
5761 -- Default_Value is resolved with the type entity in question
5763 when Aspect_Default_Value =>
5766 -- Default_Component_Value is resolved with the component type
5768 when Aspect_Default_Component_Value =>
5769 T := Component_Type (Entity (ASN));
5771 -- Aspects corresponding to attribute definition clauses
5773 when Aspect_Address =>
5774 T := RTE (RE_Address);
5776 when Aspect_Bit_Order =>
5777 T := RTE (RE_Bit_Order);
5779 when Aspect_External_Tag =>
5780 T := Standard_String;
5782 when Aspect_Storage_Pool =>
5783 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5785 when Aspect_Alignment |
5786 Aspect_Component_Size |
5787 Aspect_Machine_Radix |
5788 Aspect_Object_Size |
5790 Aspect_Storage_Size |
5791 Aspect_Stream_Size |
5792 Aspect_Value_Size =>
5795 -- Stream attribute. Special case, the expression is just an entity
5796 -- that does not need any resolution, so just analyze.
5802 Analyze (Expression (ASN));
5805 -- Same for Iterator aspects, where the expression is a function
5806 -- name. Legality rules are checked separately.
5808 when Aspect_Constant_Indexing |
5809 Aspect_Default_Iterator |
5810 Aspect_Iterator_Element |
5811 Aspect_Implicit_Dereference |
5812 Aspect_Variable_Indexing =>
5813 Analyze (Expression (ASN));
5816 -- Suppress/Unsuppress/Warnings should never be delayed
5818 when Aspect_Suppress |
5821 raise Program_Error;
5823 -- Pre/Post/Invariant/Predicate take boolean expressions
5825 when Aspect_Dynamic_Predicate |
5828 Aspect_Precondition |
5830 Aspect_Postcondition |
5832 Aspect_Static_Predicate |
5833 Aspect_Type_Invariant =>
5834 T := Standard_Boolean;
5837 -- Do the preanalyze call
5839 Preanalyze_Spec_Expression (Expression (ASN), T);
5840 end Check_Aspect_At_Freeze_Point;
5842 -----------------------------------
5843 -- Check_Constant_Address_Clause --
5844 -----------------------------------
5846 procedure Check_Constant_Address_Clause
5850 procedure Check_At_Constant_Address (Nod : Node_Id);
5851 -- Checks that the given node N represents a name whose 'Address is
5852 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5853 -- address value is the same at the point of declaration of U_Ent and at
5854 -- the time of elaboration of the address clause.
5856 procedure Check_Expr_Constants (Nod : Node_Id);
5857 -- Checks that Nod meets the requirements for a constant address clause
5858 -- in the sense of the enclosing procedure.
5860 procedure Check_List_Constants (Lst : List_Id);
5861 -- Check that all elements of list Lst meet the requirements for a
5862 -- constant address clause in the sense of the enclosing procedure.
5864 -------------------------------
5865 -- Check_At_Constant_Address --
5866 -------------------------------
5868 procedure Check_At_Constant_Address (Nod : Node_Id) is
5870 if Is_Entity_Name (Nod) then
5871 if Present (Address_Clause (Entity ((Nod)))) then
5873 ("invalid address clause for initialized object &!",
5876 ("address for& cannot" &
5877 " depend on another address clause! (RM 13.1(22))!",
5880 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
5881 and then Sloc (U_Ent) < Sloc (Entity (Nod))
5884 ("invalid address clause for initialized object &!",
5886 Error_Msg_Node_2 := U_Ent;
5888 ("\& must be defined before & (RM 13.1(22))!",
5892 elsif Nkind (Nod) = N_Selected_Component then
5894 T : constant Entity_Id := Etype (Prefix (Nod));
5897 if (Is_Record_Type (T)
5898 and then Has_Discriminants (T))
5901 and then Is_Record_Type (Designated_Type (T))
5902 and then Has_Discriminants (Designated_Type (T)))
5905 ("invalid address clause for initialized object &!",
5908 ("\address cannot depend on component" &
5909 " of discriminated record (RM 13.1(22))!",
5912 Check_At_Constant_Address (Prefix (Nod));
5916 elsif Nkind (Nod) = N_Indexed_Component then
5917 Check_At_Constant_Address (Prefix (Nod));
5918 Check_List_Constants (Expressions (Nod));
5921 Check_Expr_Constants (Nod);
5923 end Check_At_Constant_Address;
5925 --------------------------
5926 -- Check_Expr_Constants --
5927 --------------------------
5929 procedure Check_Expr_Constants (Nod : Node_Id) is
5930 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
5931 Ent : Entity_Id := Empty;
5934 if Nkind (Nod) in N_Has_Etype
5935 and then Etype (Nod) = Any_Type
5941 when N_Empty | N_Error =>
5944 when N_Identifier | N_Expanded_Name =>
5945 Ent := Entity (Nod);
5947 -- We need to look at the original node if it is different
5948 -- from the node, since we may have rewritten things and
5949 -- substituted an identifier representing the rewrite.
5951 if Original_Node (Nod) /= Nod then
5952 Check_Expr_Constants (Original_Node (Nod));
5954 -- If the node is an object declaration without initial
5955 -- value, some code has been expanded, and the expression
5956 -- is not constant, even if the constituents might be
5957 -- acceptable, as in A'Address + offset.
5959 if Ekind (Ent) = E_Variable
5961 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
5963 No (Expression (Declaration_Node (Ent)))
5966 ("invalid address clause for initialized object &!",
5969 -- If entity is constant, it may be the result of expanding
5970 -- a check. We must verify that its declaration appears
5971 -- before the object in question, else we also reject the
5974 elsif Ekind (Ent) = E_Constant
5975 and then In_Same_Source_Unit (Ent, U_Ent)
5976 and then Sloc (Ent) > Loc_U_Ent
5979 ("invalid address clause for initialized object &!",
5986 -- Otherwise look at the identifier and see if it is OK
5988 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
5989 or else Is_Type (Ent)
5994 Ekind (Ent) = E_Constant
5996 Ekind (Ent) = E_In_Parameter
5998 -- This is the case where we must have Ent defined before
5999 -- U_Ent. Clearly if they are in different units this
6000 -- requirement is met since the unit containing Ent is
6001 -- already processed.
6003 if not In_Same_Source_Unit (Ent, U_Ent) then
6006 -- Otherwise location of Ent must be before the location
6007 -- of U_Ent, that's what prior defined means.
6009 elsif Sloc (Ent) < Loc_U_Ent then
6014 ("invalid address clause for initialized object &!",
6016 Error_Msg_Node_2 := U_Ent;
6018 ("\& must be defined before & (RM 13.1(22))!",
6022 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
6023 Check_Expr_Constants (Original_Node (Nod));
6027 ("invalid address clause for initialized object &!",
6030 if Comes_From_Source (Ent) then
6032 ("\reference to variable& not allowed"
6033 & " (RM 13.1(22))!", Nod, Ent);
6036 ("non-static expression not allowed"
6037 & " (RM 13.1(22))!", Nod);
6041 when N_Integer_Literal =>
6043 -- If this is a rewritten unchecked conversion, in a system
6044 -- where Address is an integer type, always use the base type
6045 -- for a literal value. This is user-friendly and prevents
6046 -- order-of-elaboration issues with instances of unchecked
6049 if Nkind (Original_Node (Nod)) = N_Function_Call then
6050 Set_Etype (Nod, Base_Type (Etype (Nod)));
6053 when N_Real_Literal |
6055 N_Character_Literal =>
6059 Check_Expr_Constants (Low_Bound (Nod));
6060 Check_Expr_Constants (High_Bound (Nod));
6062 when N_Explicit_Dereference =>
6063 Check_Expr_Constants (Prefix (Nod));
6065 when N_Indexed_Component =>
6066 Check_Expr_Constants (Prefix (Nod));
6067 Check_List_Constants (Expressions (Nod));
6070 Check_Expr_Constants (Prefix (Nod));
6071 Check_Expr_Constants (Discrete_Range (Nod));
6073 when N_Selected_Component =>
6074 Check_Expr_Constants (Prefix (Nod));
6076 when N_Attribute_Reference =>
6077 if Attribute_Name (Nod) = Name_Address
6079 Attribute_Name (Nod) = Name_Access
6081 Attribute_Name (Nod) = Name_Unchecked_Access
6083 Attribute_Name (Nod) = Name_Unrestricted_Access
6085 Check_At_Constant_Address (Prefix (Nod));
6088 Check_Expr_Constants (Prefix (Nod));
6089 Check_List_Constants (Expressions (Nod));
6093 Check_List_Constants (Component_Associations (Nod));
6094 Check_List_Constants (Expressions (Nod));
6096 when N_Component_Association =>
6097 Check_Expr_Constants (Expression (Nod));
6099 when N_Extension_Aggregate =>
6100 Check_Expr_Constants (Ancestor_Part (Nod));
6101 Check_List_Constants (Component_Associations (Nod));
6102 Check_List_Constants (Expressions (Nod));
6107 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
6108 Check_Expr_Constants (Left_Opnd (Nod));
6109 Check_Expr_Constants (Right_Opnd (Nod));
6112 Check_Expr_Constants (Right_Opnd (Nod));
6114 when N_Type_Conversion |
6115 N_Qualified_Expression |
6117 Check_Expr_Constants (Expression (Nod));
6119 when N_Unchecked_Type_Conversion =>
6120 Check_Expr_Constants (Expression (Nod));
6122 -- If this is a rewritten unchecked conversion, subtypes in
6123 -- this node are those created within the instance. To avoid
6124 -- order of elaboration issues, replace them with their base
6125 -- types. Note that address clauses can cause order of
6126 -- elaboration problems because they are elaborated by the
6127 -- back-end at the point of definition, and may mention
6128 -- entities declared in between (as long as everything is
6129 -- static). It is user-friendly to allow unchecked conversions
6132 if Nkind (Original_Node (Nod)) = N_Function_Call then
6133 Set_Etype (Expression (Nod),
6134 Base_Type (Etype (Expression (Nod))));
6135 Set_Etype (Nod, Base_Type (Etype (Nod)));
6138 when N_Function_Call =>
6139 if not Is_Pure (Entity (Name (Nod))) then
6141 ("invalid address clause for initialized object &!",
6145 ("\function & is not pure (RM 13.1(22))!",
6146 Nod, Entity (Name (Nod)));
6149 Check_List_Constants (Parameter_Associations (Nod));
6152 when N_Parameter_Association =>
6153 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
6157 ("invalid address clause for initialized object &!",
6160 ("\must be constant defined before& (RM 13.1(22))!",
6163 end Check_Expr_Constants;
6165 --------------------------
6166 -- Check_List_Constants --
6167 --------------------------
6169 procedure Check_List_Constants (Lst : List_Id) is
6173 if Present (Lst) then
6174 Nod1 := First (Lst);
6175 while Present (Nod1) loop
6176 Check_Expr_Constants (Nod1);
6180 end Check_List_Constants;
6182 -- Start of processing for Check_Constant_Address_Clause
6185 -- If rep_clauses are to be ignored, no need for legality checks. In
6186 -- particular, no need to pester user about rep clauses that violate
6187 -- the rule on constant addresses, given that these clauses will be
6188 -- removed by Freeze before they reach the back end.
6190 if not Ignore_Rep_Clauses then
6191 Check_Expr_Constants (Expr);
6193 end Check_Constant_Address_Clause;
6195 ----------------------------------------
6196 -- Check_Record_Representation_Clause --
6197 ----------------------------------------
6199 procedure Check_Record_Representation_Clause (N : Node_Id) is
6200 Loc : constant Source_Ptr := Sloc (N);
6201 Ident : constant Node_Id := Identifier (N);
6202 Rectype : Entity_Id;
6207 Hbit : Uint := Uint_0;
6211 Max_Bit_So_Far : Uint;
6212 -- Records the maximum bit position so far. If all field positions
6213 -- are monotonically increasing, then we can skip the circuit for
6214 -- checking for overlap, since no overlap is possible.
6216 Tagged_Parent : Entity_Id := Empty;
6217 -- This is set in the case of a derived tagged type for which we have
6218 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
6219 -- positioned by record representation clauses). In this case we must
6220 -- check for overlap between components of this tagged type, and the
6221 -- components of its parent. Tagged_Parent will point to this parent
6222 -- type. For all other cases Tagged_Parent is left set to Empty.
6224 Parent_Last_Bit : Uint;
6225 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
6226 -- last bit position for any field in the parent type. We only need to
6227 -- check overlap for fields starting below this point.
6229 Overlap_Check_Required : Boolean;
6230 -- Used to keep track of whether or not an overlap check is required
6232 Overlap_Detected : Boolean := False;
6233 -- Set True if an overlap is detected
6235 Ccount : Natural := 0;
6236 -- Number of component clauses in record rep clause
6238 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
6239 -- Given two entities for record components or discriminants, checks
6240 -- if they have overlapping component clauses and issues errors if so.
6242 procedure Find_Component;
6243 -- Finds component entity corresponding to current component clause (in
6244 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
6245 -- start/stop bits for the field. If there is no matching component or
6246 -- if the matching component does not have a component clause, then
6247 -- that's an error and Comp is set to Empty, but no error message is
6248 -- issued, since the message was already given. Comp is also set to
6249 -- Empty if the current "component clause" is in fact a pragma.
6251 -----------------------------
6252 -- Check_Component_Overlap --
6253 -----------------------------
6255 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
6256 CC1 : constant Node_Id := Component_Clause (C1_Ent);
6257 CC2 : constant Node_Id := Component_Clause (C2_Ent);
6260 if Present (CC1) and then Present (CC2) then
6262 -- Exclude odd case where we have two tag fields in the same
6263 -- record, both at location zero. This seems a bit strange, but
6264 -- it seems to happen in some circumstances, perhaps on an error.
6266 if Chars (C1_Ent) = Name_uTag
6268 Chars (C2_Ent) = Name_uTag
6273 -- Here we check if the two fields overlap
6276 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
6277 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
6278 E1 : constant Uint := S1 + Esize (C1_Ent);
6279 E2 : constant Uint := S2 + Esize (C2_Ent);
6282 if E2 <= S1 or else E1 <= S2 then
6285 Error_Msg_Node_2 := Component_Name (CC2);
6286 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6287 Error_Msg_Node_1 := Component_Name (CC1);
6289 ("component& overlaps & #", Component_Name (CC1));
6290 Overlap_Detected := True;
6294 end Check_Component_Overlap;
6296 --------------------
6297 -- Find_Component --
6298 --------------------
6300 procedure Find_Component is
6302 procedure Search_Component (R : Entity_Id);
6303 -- Search components of R for a match. If found, Comp is set.
6305 ----------------------
6306 -- Search_Component --
6307 ----------------------
6309 procedure Search_Component (R : Entity_Id) is
6311 Comp := First_Component_Or_Discriminant (R);
6312 while Present (Comp) loop
6314 -- Ignore error of attribute name for component name (we
6315 -- already gave an error message for this, so no need to
6318 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
6321 exit when Chars (Comp) = Chars (Component_Name (CC));
6324 Next_Component_Or_Discriminant (Comp);
6326 end Search_Component;
6328 -- Start of processing for Find_Component
6331 -- Return with Comp set to Empty if we have a pragma
6333 if Nkind (CC) = N_Pragma then
6338 -- Search current record for matching component
6340 Search_Component (Rectype);
6342 -- If not found, maybe component of base type that is absent from
6343 -- statically constrained first subtype.
6346 Search_Component (Base_Type (Rectype));
6349 -- If no component, or the component does not reference the component
6350 -- clause in question, then there was some previous error for which
6351 -- we already gave a message, so just return with Comp Empty.
6354 or else Component_Clause (Comp) /= CC
6358 -- Normal case where we have a component clause
6361 Fbit := Component_Bit_Offset (Comp);
6362 Lbit := Fbit + Esize (Comp) - 1;
6366 -- Start of processing for Check_Record_Representation_Clause
6370 Rectype := Entity (Ident);
6372 if Rectype = Any_Type then
6375 Rectype := Underlying_Type (Rectype);
6378 -- See if we have a fully repped derived tagged type
6381 PS : constant Entity_Id := Parent_Subtype (Rectype);
6384 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
6385 Tagged_Parent := PS;
6387 -- Find maximum bit of any component of the parent type
6389 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
6390 Pcomp := First_Entity (Tagged_Parent);
6391 while Present (Pcomp) loop
6392 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
6393 if Component_Bit_Offset (Pcomp) /= No_Uint
6394 and then Known_Static_Esize (Pcomp)
6399 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
6402 Next_Entity (Pcomp);
6408 -- All done if no component clauses
6410 CC := First (Component_Clauses (N));
6416 -- If a tag is present, then create a component clause that places it
6417 -- at the start of the record (otherwise gigi may place it after other
6418 -- fields that have rep clauses).
6420 Fent := First_Entity (Rectype);
6422 if Nkind (Fent) = N_Defining_Identifier
6423 and then Chars (Fent) = Name_uTag
6425 Set_Component_Bit_Offset (Fent, Uint_0);
6426 Set_Normalized_Position (Fent, Uint_0);
6427 Set_Normalized_First_Bit (Fent, Uint_0);
6428 Set_Normalized_Position_Max (Fent, Uint_0);
6429 Init_Esize (Fent, System_Address_Size);
6431 Set_Component_Clause (Fent,
6432 Make_Component_Clause (Loc,
6433 Component_Name => Make_Identifier (Loc, Name_uTag),
6435 Position => Make_Integer_Literal (Loc, Uint_0),
6436 First_Bit => Make_Integer_Literal (Loc, Uint_0),
6438 Make_Integer_Literal (Loc,
6439 UI_From_Int (System_Address_Size))));
6441 Ccount := Ccount + 1;
6444 Max_Bit_So_Far := Uint_Minus_1;
6445 Overlap_Check_Required := False;
6447 -- Process the component clauses
6449 while Present (CC) loop
6452 if Present (Comp) then
6453 Ccount := Ccount + 1;
6455 -- We need a full overlap check if record positions non-monotonic
6457 if Fbit <= Max_Bit_So_Far then
6458 Overlap_Check_Required := True;
6461 Max_Bit_So_Far := Lbit;
6463 -- Check bit position out of range of specified size
6465 if Has_Size_Clause (Rectype)
6466 and then RM_Size (Rectype) <= Lbit
6469 ("bit number out of range of specified size",
6472 -- Check for overlap with tag field
6475 if Is_Tagged_Type (Rectype)
6476 and then Fbit < System_Address_Size
6479 ("component overlaps tag field of&",
6480 Component_Name (CC), Rectype);
6481 Overlap_Detected := True;
6489 -- Check parent overlap if component might overlap parent field
6491 if Present (Tagged_Parent)
6492 and then Fbit <= Parent_Last_Bit
6494 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
6495 while Present (Pcomp) loop
6496 if not Is_Tag (Pcomp)
6497 and then Chars (Pcomp) /= Name_uParent
6499 Check_Component_Overlap (Comp, Pcomp);
6502 Next_Component_Or_Discriminant (Pcomp);
6510 -- Now that we have processed all the component clauses, check for
6511 -- overlap. We have to leave this till last, since the components can
6512 -- appear in any arbitrary order in the representation clause.
6514 -- We do not need this check if all specified ranges were monotonic,
6515 -- as recorded by Overlap_Check_Required being False at this stage.
6517 -- This first section checks if there are any overlapping entries at
6518 -- all. It does this by sorting all entries and then seeing if there are
6519 -- any overlaps. If there are none, then that is decisive, but if there
6520 -- are overlaps, they may still be OK (they may result from fields in
6521 -- different variants).
6523 if Overlap_Check_Required then
6524 Overlap_Check1 : declare
6526 OC_Fbit : array (0 .. Ccount) of Uint;
6527 -- First-bit values for component clauses, the value is the offset
6528 -- of the first bit of the field from start of record. The zero
6529 -- entry is for use in sorting.
6531 OC_Lbit : array (0 .. Ccount) of Uint;
6532 -- Last-bit values for component clauses, the value is the offset
6533 -- of the last bit of the field from start of record. The zero
6534 -- entry is for use in sorting.
6536 OC_Count : Natural := 0;
6537 -- Count of entries in OC_Fbit and OC_Lbit
6539 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6540 -- Compare routine for Sort
6542 procedure OC_Move (From : Natural; To : Natural);
6543 -- Move routine for Sort
6545 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6551 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6553 return OC_Fbit (Op1) < OC_Fbit (Op2);
6560 procedure OC_Move (From : Natural; To : Natural) is
6562 OC_Fbit (To) := OC_Fbit (From);
6563 OC_Lbit (To) := OC_Lbit (From);
6566 -- Start of processing for Overlap_Check
6569 CC := First (Component_Clauses (N));
6570 while Present (CC) loop
6572 -- Exclude component clause already marked in error
6574 if not Error_Posted (CC) then
6577 if Present (Comp) then
6578 OC_Count := OC_Count + 1;
6579 OC_Fbit (OC_Count) := Fbit;
6580 OC_Lbit (OC_Count) := Lbit;
6587 Sorting.Sort (OC_Count);
6589 Overlap_Check_Required := False;
6590 for J in 1 .. OC_Count - 1 loop
6591 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6592 Overlap_Check_Required := True;
6599 -- If Overlap_Check_Required is still True, then we have to do the full
6600 -- scale overlap check, since we have at least two fields that do
6601 -- overlap, and we need to know if that is OK since they are in
6602 -- different variant, or whether we have a definite problem.
6604 if Overlap_Check_Required then
6605 Overlap_Check2 : declare
6606 C1_Ent, C2_Ent : Entity_Id;
6607 -- Entities of components being checked for overlap
6610 -- Component_List node whose Component_Items are being checked
6613 -- Component declaration for component being checked
6616 C1_Ent := First_Entity (Base_Type (Rectype));
6618 -- Loop through all components in record. For each component check
6619 -- for overlap with any of the preceding elements on the component
6620 -- list containing the component and also, if the component is in
6621 -- a variant, check against components outside the case structure.
6622 -- This latter test is repeated recursively up the variant tree.
6624 Main_Component_Loop : while Present (C1_Ent) loop
6625 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6626 goto Continue_Main_Component_Loop;
6629 -- Skip overlap check if entity has no declaration node. This
6630 -- happens with discriminants in constrained derived types.
6631 -- Possibly we are missing some checks as a result, but that
6632 -- does not seem terribly serious.
6634 if No (Declaration_Node (C1_Ent)) then
6635 goto Continue_Main_Component_Loop;
6638 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6640 -- Loop through component lists that need checking. Check the
6641 -- current component list and all lists in variants above us.
6643 Component_List_Loop : loop
6645 -- If derived type definition, go to full declaration
6646 -- If at outer level, check discriminants if there are any.
6648 if Nkind (Clist) = N_Derived_Type_Definition then
6649 Clist := Parent (Clist);
6652 -- Outer level of record definition, check discriminants
6654 if Nkind_In (Clist, N_Full_Type_Declaration,
6655 N_Private_Type_Declaration)
6657 if Has_Discriminants (Defining_Identifier (Clist)) then
6659 First_Discriminant (Defining_Identifier (Clist));
6660 while Present (C2_Ent) loop
6661 exit when C1_Ent = C2_Ent;
6662 Check_Component_Overlap (C1_Ent, C2_Ent);
6663 Next_Discriminant (C2_Ent);
6667 -- Record extension case
6669 elsif Nkind (Clist) = N_Derived_Type_Definition then
6672 -- Otherwise check one component list
6675 Citem := First (Component_Items (Clist));
6676 while Present (Citem) loop
6677 if Nkind (Citem) = N_Component_Declaration then
6678 C2_Ent := Defining_Identifier (Citem);
6679 exit when C1_Ent = C2_Ent;
6680 Check_Component_Overlap (C1_Ent, C2_Ent);
6687 -- Check for variants above us (the parent of the Clist can
6688 -- be a variant, in which case its parent is a variant part,
6689 -- and the parent of the variant part is a component list
6690 -- whose components must all be checked against the current
6691 -- component for overlap).
6693 if Nkind (Parent (Clist)) = N_Variant then
6694 Clist := Parent (Parent (Parent (Clist)));
6696 -- Check for possible discriminant part in record, this
6697 -- is treated essentially as another level in the
6698 -- recursion. For this case the parent of the component
6699 -- list is the record definition, and its parent is the
6700 -- full type declaration containing the discriminant
6703 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6704 Clist := Parent (Parent ((Clist)));
6706 -- If neither of these two cases, we are at the top of
6710 exit Component_List_Loop;
6712 end loop Component_List_Loop;
6714 <<Continue_Main_Component_Loop>>
6715 Next_Entity (C1_Ent);
6717 end loop Main_Component_Loop;
6721 -- The following circuit deals with warning on record holes (gaps). We
6722 -- skip this check if overlap was detected, since it makes sense for the
6723 -- programmer to fix this illegality before worrying about warnings.
6725 if not Overlap_Detected and Warn_On_Record_Holes then
6726 Record_Hole_Check : declare
6727 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6728 -- Full declaration of record type
6730 procedure Check_Component_List
6734 -- Check component list CL for holes. The starting bit should be
6735 -- Sbit. which is zero for the main record component list and set
6736 -- appropriately for recursive calls for variants. DS is set to
6737 -- a list of discriminant specifications to be included in the
6738 -- consideration of components. It is No_List if none to consider.
6740 --------------------------
6741 -- Check_Component_List --
6742 --------------------------
6744 procedure Check_Component_List
6752 Compl := Integer (List_Length (Component_Items (CL)));
6754 if DS /= No_List then
6755 Compl := Compl + Integer (List_Length (DS));
6759 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6760 -- Gather components (zero entry is for sort routine)
6762 Ncomps : Natural := 0;
6763 -- Number of entries stored in Comps (starting at Comps (1))
6766 -- One component item or discriminant specification
6769 -- Starting bit for next component
6777 function Lt (Op1, Op2 : Natural) return Boolean;
6778 -- Compare routine for Sort
6780 procedure Move (From : Natural; To : Natural);
6781 -- Move routine for Sort
6783 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6789 function Lt (Op1, Op2 : Natural) return Boolean is
6791 return Component_Bit_Offset (Comps (Op1))
6793 Component_Bit_Offset (Comps (Op2));
6800 procedure Move (From : Natural; To : Natural) is
6802 Comps (To) := Comps (From);
6806 -- Gather discriminants into Comp
6808 if DS /= No_List then
6809 Citem := First (DS);
6810 while Present (Citem) loop
6811 if Nkind (Citem) = N_Discriminant_Specification then
6813 Ent : constant Entity_Id :=
6814 Defining_Identifier (Citem);
6816 if Ekind (Ent) = E_Discriminant then
6817 Ncomps := Ncomps + 1;
6818 Comps (Ncomps) := Ent;
6827 -- Gather component entities into Comp
6829 Citem := First (Component_Items (CL));
6830 while Present (Citem) loop
6831 if Nkind (Citem) = N_Component_Declaration then
6832 Ncomps := Ncomps + 1;
6833 Comps (Ncomps) := Defining_Identifier (Citem);
6839 -- Now sort the component entities based on the first bit.
6840 -- Note we already know there are no overlapping components.
6842 Sorting.Sort (Ncomps);
6844 -- Loop through entries checking for holes
6847 for J in 1 .. Ncomps loop
6849 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6851 if Error_Msg_Uint_1 > 0 then
6853 ("?^-bit gap before component&",
6854 Component_Name (Component_Clause (CEnt)), CEnt);
6857 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
6860 -- Process variant parts recursively if present
6862 if Present (Variant_Part (CL)) then
6863 Variant := First (Variants (Variant_Part (CL)));
6864 while Present (Variant) loop
6865 Check_Component_List
6866 (Component_List (Variant), Nbit, No_List);
6871 end Check_Component_List;
6873 -- Start of processing for Record_Hole_Check
6880 if Is_Tagged_Type (Rectype) then
6881 Sbit := UI_From_Int (System_Address_Size);
6886 if Nkind (Decl) = N_Full_Type_Declaration
6887 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6889 Check_Component_List
6890 (Component_List (Type_Definition (Decl)),
6892 Discriminant_Specifications (Decl));
6895 end Record_Hole_Check;
6898 -- For records that have component clauses for all components, and whose
6899 -- size is less than or equal to 32, we need to know the size in the
6900 -- front end to activate possible packed array processing where the
6901 -- component type is a record.
6903 -- At this stage Hbit + 1 represents the first unused bit from all the
6904 -- component clauses processed, so if the component clauses are
6905 -- complete, then this is the length of the record.
6907 -- For records longer than System.Storage_Unit, and for those where not
6908 -- all components have component clauses, the back end determines the
6909 -- length (it may for example be appropriate to round up the size
6910 -- to some convenient boundary, based on alignment considerations, etc).
6912 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
6914 -- Nothing to do if at least one component has no component clause
6916 Comp := First_Component_Or_Discriminant (Rectype);
6917 while Present (Comp) loop
6918 exit when No (Component_Clause (Comp));
6919 Next_Component_Or_Discriminant (Comp);
6922 -- If we fall out of loop, all components have component clauses
6923 -- and so we can set the size to the maximum value.
6926 Set_RM_Size (Rectype, Hbit + 1);
6929 end Check_Record_Representation_Clause;
6935 procedure Check_Size
6939 Biased : out Boolean)
6941 UT : constant Entity_Id := Underlying_Type (T);
6947 -- Dismiss cases for generic types or types with previous errors
6950 or else UT = Any_Type
6951 or else Is_Generic_Type (UT)
6952 or else Is_Generic_Type (Root_Type (UT))
6956 -- Check case of bit packed array
6958 elsif Is_Array_Type (UT)
6959 and then Known_Static_Component_Size (UT)
6960 and then Is_Bit_Packed_Array (UT)
6968 Asiz := Component_Size (UT);
6969 Indx := First_Index (UT);
6971 Ityp := Etype (Indx);
6973 -- If non-static bound, then we are not in the business of
6974 -- trying to check the length, and indeed an error will be
6975 -- issued elsewhere, since sizes of non-static array types
6976 -- cannot be set implicitly or explicitly.
6978 if not Is_Static_Subtype (Ityp) then
6982 -- Otherwise accumulate next dimension
6984 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
6985 Expr_Value (Type_Low_Bound (Ityp)) +
6989 exit when No (Indx);
6995 Error_Msg_Uint_1 := Asiz;
6997 ("size for& too small, minimum allowed is ^", N, T);
6998 Set_Esize (T, Asiz);
6999 Set_RM_Size (T, Asiz);
7003 -- All other composite types are ignored
7005 elsif Is_Composite_Type (UT) then
7008 -- For fixed-point types, don't check minimum if type is not frozen,
7009 -- since we don't know all the characteristics of the type that can
7010 -- affect the size (e.g. a specified small) till freeze time.
7012 elsif Is_Fixed_Point_Type (UT)
7013 and then not Is_Frozen (UT)
7017 -- Cases for which a minimum check is required
7020 -- Ignore if specified size is correct for the type
7022 if Known_Esize (UT) and then Siz = Esize (UT) then
7026 -- Otherwise get minimum size
7028 M := UI_From_Int (Minimum_Size (UT));
7032 -- Size is less than minimum size, but one possibility remains
7033 -- that we can manage with the new size if we bias the type.
7035 M := UI_From_Int (Minimum_Size (UT, Biased => True));
7038 Error_Msg_Uint_1 := M;
7040 ("size for& too small, minimum allowed is ^", N, T);
7050 -------------------------
7051 -- Get_Alignment_Value --
7052 -------------------------
7054 function Get_Alignment_Value (Expr : Node_Id) return Uint is
7055 Align : constant Uint := Static_Integer (Expr);
7058 if Align = No_Uint then
7061 elsif Align <= 0 then
7062 Error_Msg_N ("alignment value must be positive", Expr);
7066 for J in Int range 0 .. 64 loop
7068 M : constant Uint := Uint_2 ** J;
7071 exit when M = Align;
7075 ("alignment value must be power of 2", Expr);
7083 end Get_Alignment_Value;
7089 procedure Initialize is
7091 Address_Clause_Checks.Init;
7092 Independence_Checks.Init;
7093 Unchecked_Conversions.Init;
7096 -------------------------
7097 -- Is_Operational_Item --
7098 -------------------------
7100 function Is_Operational_Item (N : Node_Id) return Boolean is
7102 if Nkind (N) /= N_Attribute_Definition_Clause then
7106 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
7108 return Id = Attribute_Input
7109 or else Id = Attribute_Output
7110 or else Id = Attribute_Read
7111 or else Id = Attribute_Write
7112 or else Id = Attribute_External_Tag;
7115 end Is_Operational_Item;
7121 function Minimum_Size
7123 Biased : Boolean := False) return Nat
7125 Lo : Uint := No_Uint;
7126 Hi : Uint := No_Uint;
7127 LoR : Ureal := No_Ureal;
7128 HiR : Ureal := No_Ureal;
7129 LoSet : Boolean := False;
7130 HiSet : Boolean := False;
7134 R_Typ : constant Entity_Id := Root_Type (T);
7137 -- If bad type, return 0
7139 if T = Any_Type then
7142 -- For generic types, just return zero. There cannot be any legitimate
7143 -- need to know such a size, but this routine may be called with a
7144 -- generic type as part of normal processing.
7146 elsif Is_Generic_Type (R_Typ)
7147 or else R_Typ = Any_Type
7151 -- Access types. Normally an access type cannot have a size smaller
7152 -- than the size of System.Address. The exception is on VMS, where
7153 -- we have short and long addresses, and it is possible for an access
7154 -- type to have a short address size (and thus be less than the size
7155 -- of System.Address itself). We simply skip the check for VMS, and
7156 -- leave it to the back end to do the check.
7158 elsif Is_Access_Type (T) then
7159 if OpenVMS_On_Target then
7162 return System_Address_Size;
7165 -- Floating-point types
7167 elsif Is_Floating_Point_Type (T) then
7168 return UI_To_Int (Esize (R_Typ));
7172 elsif Is_Discrete_Type (T) then
7174 -- The following loop is looking for the nearest compile time known
7175 -- bounds following the ancestor subtype chain. The idea is to find
7176 -- the most restrictive known bounds information.
7180 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7185 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
7186 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
7193 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
7194 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
7200 Ancest := Ancestor_Subtype (Ancest);
7203 Ancest := Base_Type (T);
7205 if Is_Generic_Type (Ancest) then
7211 -- Fixed-point types. We can't simply use Expr_Value to get the
7212 -- Corresponding_Integer_Value values of the bounds, since these do not
7213 -- get set till the type is frozen, and this routine can be called
7214 -- before the type is frozen. Similarly the test for bounds being static
7215 -- needs to include the case where we have unanalyzed real literals for
7218 elsif Is_Fixed_Point_Type (T) then
7220 -- The following loop is looking for the nearest compile time known
7221 -- bounds following the ancestor subtype chain. The idea is to find
7222 -- the most restrictive known bounds information.
7226 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7230 -- Note: In the following two tests for LoSet and HiSet, it may
7231 -- seem redundant to test for N_Real_Literal here since normally
7232 -- one would assume that the test for the value being known at
7233 -- compile time includes this case. However, there is a glitch.
7234 -- If the real literal comes from folding a non-static expression,
7235 -- then we don't consider any non- static expression to be known
7236 -- at compile time if we are in configurable run time mode (needed
7237 -- in some cases to give a clearer definition of what is and what
7238 -- is not accepted). So the test is indeed needed. Without it, we
7239 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
7242 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
7243 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
7245 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
7252 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
7253 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
7255 HiR := Expr_Value_R (Type_High_Bound (Ancest));
7261 Ancest := Ancestor_Subtype (Ancest);
7264 Ancest := Base_Type (T);
7266 if Is_Generic_Type (Ancest) then
7272 Lo := UR_To_Uint (LoR / Small_Value (T));
7273 Hi := UR_To_Uint (HiR / Small_Value (T));
7275 -- No other types allowed
7278 raise Program_Error;
7281 -- Fall through with Hi and Lo set. Deal with biased case
7284 and then not Is_Fixed_Point_Type (T)
7285 and then not (Is_Enumeration_Type (T)
7286 and then Has_Non_Standard_Rep (T)))
7287 or else Has_Biased_Representation (T)
7293 -- Signed case. Note that we consider types like range 1 .. -1 to be
7294 -- signed for the purpose of computing the size, since the bounds have
7295 -- to be accommodated in the base type.
7297 if Lo < 0 or else Hi < 0 then
7301 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
7302 -- Note that we accommodate the case where the bounds cross. This
7303 -- can happen either because of the way the bounds are declared
7304 -- or because of the algorithm in Freeze_Fixed_Point_Type.
7318 -- If both bounds are positive, make sure that both are represen-
7319 -- table in the case where the bounds are crossed. This can happen
7320 -- either because of the way the bounds are declared, or because of
7321 -- the algorithm in Freeze_Fixed_Point_Type.
7327 -- S = size, (can accommodate 0 .. (2**size - 1))
7330 while Hi >= Uint_2 ** S loop
7338 ---------------------------
7339 -- New_Stream_Subprogram --
7340 ---------------------------
7342 procedure New_Stream_Subprogram
7346 Nam : TSS_Name_Type)
7348 Loc : constant Source_Ptr := Sloc (N);
7349 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
7350 Subp_Id : Entity_Id;
7351 Subp_Decl : Node_Id;
7355 Defer_Declaration : constant Boolean :=
7356 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
7357 -- For a tagged type, there is a declaration for each stream attribute
7358 -- at the freeze point, and we must generate only a completion of this
7359 -- declaration. We do the same for private types, because the full view
7360 -- might be tagged. Otherwise we generate a declaration at the point of
7361 -- the attribute definition clause.
7363 function Build_Spec return Node_Id;
7364 -- Used for declaration and renaming declaration, so that this is
7365 -- treated as a renaming_as_body.
7371 function Build_Spec return Node_Id is
7372 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
7375 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
7378 Subp_Id := Make_Defining_Identifier (Loc, Sname);
7380 -- S : access Root_Stream_Type'Class
7382 Formals := New_List (
7383 Make_Parameter_Specification (Loc,
7384 Defining_Identifier =>
7385 Make_Defining_Identifier (Loc, Name_S),
7387 Make_Access_Definition (Loc,
7390 Designated_Type (Etype (F)), Loc))));
7392 if Nam = TSS_Stream_Input then
7393 Spec := Make_Function_Specification (Loc,
7394 Defining_Unit_Name => Subp_Id,
7395 Parameter_Specifications => Formals,
7396 Result_Definition => T_Ref);
7401 Make_Parameter_Specification (Loc,
7402 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
7403 Out_Present => Out_P,
7404 Parameter_Type => T_Ref));
7407 Make_Procedure_Specification (Loc,
7408 Defining_Unit_Name => Subp_Id,
7409 Parameter_Specifications => Formals);
7415 -- Start of processing for New_Stream_Subprogram
7418 F := First_Formal (Subp);
7420 if Ekind (Subp) = E_Procedure then
7421 Etyp := Etype (Next_Formal (F));
7423 Etyp := Etype (Subp);
7426 -- Prepare subprogram declaration and insert it as an action on the
7427 -- clause node. The visibility for this entity is used to test for
7428 -- visibility of the attribute definition clause (in the sense of
7429 -- 8.3(23) as amended by AI-195).
7431 if not Defer_Declaration then
7433 Make_Subprogram_Declaration (Loc,
7434 Specification => Build_Spec);
7436 -- For a tagged type, there is always a visible declaration for each
7437 -- stream TSS (it is a predefined primitive operation), and the
7438 -- completion of this declaration occurs at the freeze point, which is
7439 -- not always visible at places where the attribute definition clause is
7440 -- visible. So, we create a dummy entity here for the purpose of
7441 -- tracking the visibility of the attribute definition clause itself.
7445 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
7447 Make_Object_Declaration (Loc,
7448 Defining_Identifier => Subp_Id,
7449 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
7452 Insert_Action (N, Subp_Decl);
7453 Set_Entity (N, Subp_Id);
7456 Make_Subprogram_Renaming_Declaration (Loc,
7457 Specification => Build_Spec,
7458 Name => New_Reference_To (Subp, Loc));
7460 if Defer_Declaration then
7461 Set_TSS (Base_Type (Ent), Subp_Id);
7463 Insert_Action (N, Subp_Decl);
7464 Copy_TSS (Subp_Id, Base_Type (Ent));
7466 end New_Stream_Subprogram;
7468 ------------------------
7469 -- Rep_Item_Too_Early --
7470 ------------------------
7472 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
7474 -- Cannot apply non-operational rep items to generic types
7476 if Is_Operational_Item (N) then
7480 and then Is_Generic_Type (Root_Type (T))
7482 Error_Msg_N ("representation item not allowed for generic type", N);
7486 -- Otherwise check for incomplete type
7488 if Is_Incomplete_Or_Private_Type (T)
7489 and then No (Underlying_Type (T))
7491 (Nkind (N) /= N_Pragma
7492 or else Get_Pragma_Id (N) /= Pragma_Import)
7495 ("representation item must be after full type declaration", N);
7498 -- If the type has incomplete components, a representation clause is
7499 -- illegal but stream attributes and Convention pragmas are correct.
7501 elsif Has_Private_Component (T) then
7502 if Nkind (N) = N_Pragma then
7506 ("representation item must appear after type is fully defined",
7513 end Rep_Item_Too_Early;
7515 -----------------------
7516 -- Rep_Item_Too_Late --
7517 -----------------------
7519 function Rep_Item_Too_Late
7522 FOnly : Boolean := False) return Boolean
7525 Parent_Type : Entity_Id;
7528 -- Output the too late message. Note that this is not considered a
7529 -- serious error, since the effect is simply that we ignore the
7530 -- representation clause in this case.
7536 procedure Too_Late is
7538 Error_Msg_N ("|representation item appears too late!", N);
7541 -- Start of processing for Rep_Item_Too_Late
7544 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7545 -- types, which may be frozen if they appear in a representation clause
7546 -- for a local type.
7549 and then not From_With_Type (T)
7552 S := First_Subtype (T);
7554 if Present (Freeze_Node (S)) then
7556 ("?no more representation items for }", Freeze_Node (S), S);
7561 -- Check for case of non-tagged derived type whose parent either has
7562 -- primitive operations, or is a by reference type (RM 13.1(10)).
7566 and then Is_Derived_Type (T)
7567 and then not Is_Tagged_Type (T)
7569 Parent_Type := Etype (Base_Type (T));
7571 if Has_Primitive_Operations (Parent_Type) then
7574 ("primitive operations already defined for&!", N, Parent_Type);
7577 elsif Is_By_Reference_Type (Parent_Type) then
7580 ("parent type & is a by reference type!", N, Parent_Type);
7585 -- No error, link item into head of chain of rep items for the entity,
7586 -- but avoid chaining if we have an overloadable entity, and the pragma
7587 -- is one that can apply to multiple overloaded entities.
7589 if Is_Overloadable (T)
7590 and then Nkind (N) = N_Pragma
7593 Pname : constant Name_Id := Pragma_Name (N);
7595 if Pname = Name_Convention or else
7596 Pname = Name_Import or else
7597 Pname = Name_Export or else
7598 Pname = Name_External or else
7599 Pname = Name_Interface
7606 Record_Rep_Item (T, N);
7608 end Rep_Item_Too_Late;
7610 -------------------------------------
7611 -- Replace_Type_References_Generic --
7612 -------------------------------------
7614 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7616 function Replace_Node (N : Node_Id) return Traverse_Result;
7617 -- Processes a single node in the traversal procedure below, checking
7618 -- if node N should be replaced, and if so, doing the replacement.
7620 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7621 -- This instantiation provides the body of Replace_Type_References
7627 function Replace_Node (N : Node_Id) return Traverse_Result is
7632 -- Case of identifier
7634 if Nkind (N) = N_Identifier then
7636 -- If not the type name, all done with this node
7638 if Chars (N) /= TName then
7641 -- Otherwise do the replacement and we are done with this node
7644 Replace_Type_Reference (N);
7648 -- Case of selected component (which is what a qualification
7649 -- looks like in the unanalyzed tree, which is what we have.
7651 elsif Nkind (N) = N_Selected_Component then
7653 -- If selector name is not our type, keeping going (we might
7654 -- still have an occurrence of the type in the prefix).
7656 if Nkind (Selector_Name (N)) /= N_Identifier
7657 or else Chars (Selector_Name (N)) /= TName
7661 -- Selector name is our type, check qualification
7664 -- Loop through scopes and prefixes, doing comparison
7669 -- Continue if no more scopes or scope with no name
7671 if No (S) or else Nkind (S) not in N_Has_Chars then
7675 -- Do replace if prefix is an identifier matching the
7676 -- scope that we are currently looking at.
7678 if Nkind (P) = N_Identifier
7679 and then Chars (P) = Chars (S)
7681 Replace_Type_Reference (N);
7685 -- Go check scope above us if prefix is itself of the
7686 -- form of a selected component, whose selector matches
7687 -- the scope we are currently looking at.
7689 if Nkind (P) = N_Selected_Component
7690 and then Nkind (Selector_Name (P)) = N_Identifier
7691 and then Chars (Selector_Name (P)) = Chars (S)
7696 -- For anything else, we don't have a match, so keep on
7697 -- going, there are still some weird cases where we may
7698 -- still have a replacement within the prefix.
7706 -- Continue for any other node kind
7714 Replace_Type_Refs (N);
7715 end Replace_Type_References_Generic;
7717 -------------------------
7718 -- Same_Representation --
7719 -------------------------
7721 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7722 T1 : constant Entity_Id := Underlying_Type (Typ1);
7723 T2 : constant Entity_Id := Underlying_Type (Typ2);
7726 -- A quick check, if base types are the same, then we definitely have
7727 -- the same representation, because the subtype specific representation
7728 -- attributes (Size and Alignment) do not affect representation from
7729 -- the point of view of this test.
7731 if Base_Type (T1) = Base_Type (T2) then
7734 elsif Is_Private_Type (Base_Type (T2))
7735 and then Base_Type (T1) = Full_View (Base_Type (T2))
7740 -- Tagged types never have differing representations
7742 if Is_Tagged_Type (T1) then
7746 -- Representations are definitely different if conventions differ
7748 if Convention (T1) /= Convention (T2) then
7752 -- Representations are different if component alignments differ
7754 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7756 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7757 and then Component_Alignment (T1) /= Component_Alignment (T2)
7762 -- For arrays, the only real issue is component size. If we know the
7763 -- component size for both arrays, and it is the same, then that's
7764 -- good enough to know we don't have a change of representation.
7766 if Is_Array_Type (T1) then
7767 if Known_Component_Size (T1)
7768 and then Known_Component_Size (T2)
7769 and then Component_Size (T1) = Component_Size (T2)
7771 if VM_Target = No_VM then
7774 -- In VM targets the representation of arrays with aliased
7775 -- components differs from arrays with non-aliased components
7778 return Has_Aliased_Components (Base_Type (T1))
7780 Has_Aliased_Components (Base_Type (T2));
7785 -- Types definitely have same representation if neither has non-standard
7786 -- representation since default representations are always consistent.
7787 -- If only one has non-standard representation, and the other does not,
7788 -- then we consider that they do not have the same representation. They
7789 -- might, but there is no way of telling early enough.
7791 if Has_Non_Standard_Rep (T1) then
7792 if not Has_Non_Standard_Rep (T2) then
7796 return not Has_Non_Standard_Rep (T2);
7799 -- Here the two types both have non-standard representation, and we need
7800 -- to determine if they have the same non-standard representation.
7802 -- For arrays, we simply need to test if the component sizes are the
7803 -- same. Pragma Pack is reflected in modified component sizes, so this
7804 -- check also deals with pragma Pack.
7806 if Is_Array_Type (T1) then
7807 return Component_Size (T1) = Component_Size (T2);
7809 -- Tagged types always have the same representation, because it is not
7810 -- possible to specify different representations for common fields.
7812 elsif Is_Tagged_Type (T1) then
7815 -- Case of record types
7817 elsif Is_Record_Type (T1) then
7819 -- Packed status must conform
7821 if Is_Packed (T1) /= Is_Packed (T2) then
7824 -- Otherwise we must check components. Typ2 maybe a constrained
7825 -- subtype with fewer components, so we compare the components
7826 -- of the base types.
7829 Record_Case : declare
7830 CD1, CD2 : Entity_Id;
7832 function Same_Rep return Boolean;
7833 -- CD1 and CD2 are either components or discriminants. This
7834 -- function tests whether the two have the same representation
7840 function Same_Rep return Boolean is
7842 if No (Component_Clause (CD1)) then
7843 return No (Component_Clause (CD2));
7847 Present (Component_Clause (CD2))
7849 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7851 Esize (CD1) = Esize (CD2);
7855 -- Start of processing for Record_Case
7858 if Has_Discriminants (T1) then
7859 CD1 := First_Discriminant (T1);
7860 CD2 := First_Discriminant (T2);
7862 -- The number of discriminants may be different if the
7863 -- derived type has fewer (constrained by values). The
7864 -- invisible discriminants retain the representation of
7865 -- the original, so the discrepancy does not per se
7866 -- indicate a different representation.
7869 and then Present (CD2)
7871 if not Same_Rep then
7874 Next_Discriminant (CD1);
7875 Next_Discriminant (CD2);
7880 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
7881 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
7883 while Present (CD1) loop
7884 if not Same_Rep then
7887 Next_Component (CD1);
7888 Next_Component (CD2);
7896 -- For enumeration types, we must check each literal to see if the
7897 -- representation is the same. Note that we do not permit enumeration
7898 -- representation clauses for Character and Wide_Character, so these
7899 -- cases were already dealt with.
7901 elsif Is_Enumeration_Type (T1) then
7902 Enumeration_Case : declare
7906 L1 := First_Literal (T1);
7907 L2 := First_Literal (T2);
7909 while Present (L1) loop
7910 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
7920 end Enumeration_Case;
7922 -- Any other types have the same representation for these purposes
7927 end Same_Representation;
7933 procedure Set_Biased
7937 Biased : Boolean := True)
7941 Set_Has_Biased_Representation (E);
7943 if Warn_On_Biased_Representation then
7945 ("?" & Msg & " forces biased representation for&", N, E);
7950 --------------------
7951 -- Set_Enum_Esize --
7952 --------------------
7954 procedure Set_Enum_Esize (T : Entity_Id) is
7962 -- Find the minimum standard size (8,16,32,64) that fits
7964 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
7965 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
7968 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
7969 Sz := Standard_Character_Size; -- May be > 8 on some targets
7971 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
7974 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
7977 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
7982 if Hi < Uint_2**08 then
7983 Sz := Standard_Character_Size; -- May be > 8 on some targets
7985 elsif Hi < Uint_2**16 then
7988 elsif Hi < Uint_2**32 then
7991 else pragma Assert (Hi < Uint_2**63);
7996 -- That minimum is the proper size unless we have a foreign convention
7997 -- and the size required is 32 or less, in which case we bump the size
7998 -- up to 32. This is required for C and C++ and seems reasonable for
7999 -- all other foreign conventions.
8001 if Has_Foreign_Convention (T)
8002 and then Esize (T) < Standard_Integer_Size
8004 Init_Esize (T, Standard_Integer_Size);
8010 ------------------------------
8011 -- Validate_Address_Clauses --
8012 ------------------------------
8014 procedure Validate_Address_Clauses is
8016 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
8018 ACCR : Address_Clause_Check_Record
8019 renames Address_Clause_Checks.Table (J);
8030 -- Skip processing of this entry if warning already posted
8032 if not Address_Warning_Posted (ACCR.N) then
8034 Expr := Original_Node (Expression (ACCR.N));
8038 X_Alignment := Alignment (ACCR.X);
8039 Y_Alignment := Alignment (ACCR.Y);
8041 -- Similarly obtain sizes
8043 X_Size := Esize (ACCR.X);
8044 Y_Size := Esize (ACCR.Y);
8046 -- Check for large object overlaying smaller one
8049 and then X_Size > Uint_0
8050 and then X_Size > Y_Size
8053 ("?& overlays smaller object", ACCR.N, ACCR.X);
8055 ("\?program execution may be erroneous", ACCR.N);
8056 Error_Msg_Uint_1 := X_Size;
8058 ("\?size of & is ^", ACCR.N, ACCR.X);
8059 Error_Msg_Uint_1 := Y_Size;
8061 ("\?size of & is ^", ACCR.N, ACCR.Y);
8063 -- Check for inadequate alignment, both of the base object
8064 -- and of the offset, if any.
8066 -- Note: we do not check the alignment if we gave a size
8067 -- warning, since it would likely be redundant.
8069 elsif Y_Alignment /= Uint_0
8070 and then (Y_Alignment < X_Alignment
8073 Nkind (Expr) = N_Attribute_Reference
8075 Attribute_Name (Expr) = Name_Address
8077 Has_Compatible_Alignment
8078 (ACCR.X, Prefix (Expr))
8079 /= Known_Compatible))
8082 ("?specified address for& may be inconsistent "
8086 ("\?program execution may be erroneous (RM 13.3(27))",
8088 Error_Msg_Uint_1 := X_Alignment;
8090 ("\?alignment of & is ^",
8092 Error_Msg_Uint_1 := Y_Alignment;
8094 ("\?alignment of & is ^",
8096 if Y_Alignment >= X_Alignment then
8098 ("\?but offset is not multiple of alignment",
8105 end Validate_Address_Clauses;
8107 ---------------------------
8108 -- Validate_Independence --
8109 ---------------------------
8111 procedure Validate_Independence is
8112 SU : constant Uint := UI_From_Int (System_Storage_Unit);
8120 procedure Check_Array_Type (Atyp : Entity_Id);
8121 -- Checks if the array type Atyp has independent components, and
8122 -- if not, outputs an appropriate set of error messages.
8124 procedure No_Independence;
8125 -- Output message that independence cannot be guaranteed
8127 function OK_Component (C : Entity_Id) return Boolean;
8128 -- Checks one component to see if it is independently accessible, and
8129 -- if so yields True, otherwise yields False if independent access
8130 -- cannot be guaranteed. This is a conservative routine, it only
8131 -- returns True if it knows for sure, it returns False if it knows
8132 -- there is a problem, or it cannot be sure there is no problem.
8134 procedure Reason_Bad_Component (C : Entity_Id);
8135 -- Outputs continuation message if a reason can be determined for
8136 -- the component C being bad.
8138 ----------------------
8139 -- Check_Array_Type --
8140 ----------------------
8142 procedure Check_Array_Type (Atyp : Entity_Id) is
8143 Ctyp : constant Entity_Id := Component_Type (Atyp);
8146 -- OK if no alignment clause, no pack, and no component size
8148 if not Has_Component_Size_Clause (Atyp)
8149 and then not Has_Alignment_Clause (Atyp)
8150 and then not Is_Packed (Atyp)
8155 -- Check actual component size
8157 if not Known_Component_Size (Atyp)
8158 or else not (Addressable (Component_Size (Atyp))
8159 and then Component_Size (Atyp) < 64)
8160 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
8164 -- Bad component size, check reason
8166 if Has_Component_Size_Clause (Atyp) then
8168 Get_Attribute_Definition_Clause
8169 (Atyp, Attribute_Component_Size);
8172 Error_Msg_Sloc := Sloc (P);
8173 Error_Msg_N ("\because of Component_Size clause#", N);
8178 if Is_Packed (Atyp) then
8179 P := Get_Rep_Pragma (Atyp, Name_Pack);
8182 Error_Msg_Sloc := Sloc (P);
8183 Error_Msg_N ("\because of pragma Pack#", N);
8188 -- No reason found, just return
8193 -- Array type is OK independence-wise
8196 end Check_Array_Type;
8198 ---------------------
8199 -- No_Independence --
8200 ---------------------
8202 procedure No_Independence is
8204 if Pragma_Name (N) = Name_Independent then
8206 ("independence cannot be guaranteed for&", N, E);
8209 ("independent components cannot be guaranteed for&", N, E);
8211 end No_Independence;
8217 function OK_Component (C : Entity_Id) return Boolean is
8218 Rec : constant Entity_Id := Scope (C);
8219 Ctyp : constant Entity_Id := Etype (C);
8222 -- OK if no component clause, no Pack, and no alignment clause
8224 if No (Component_Clause (C))
8225 and then not Is_Packed (Rec)
8226 and then not Has_Alignment_Clause (Rec)
8231 -- Here we look at the actual component layout. A component is
8232 -- addressable if its size is a multiple of the Esize of the
8233 -- component type, and its starting position in the record has
8234 -- appropriate alignment, and the record itself has appropriate
8235 -- alignment to guarantee the component alignment.
8237 -- Make sure sizes are static, always assume the worst for any
8238 -- cases where we cannot check static values.
8240 if not (Known_Static_Esize (C)
8241 and then Known_Static_Esize (Ctyp))
8246 -- Size of component must be addressable or greater than 64 bits
8247 -- and a multiple of bytes.
8249 if not Addressable (Esize (C))
8250 and then Esize (C) < Uint_64
8255 -- Check size is proper multiple
8257 if Esize (C) mod Esize (Ctyp) /= 0 then
8261 -- Check alignment of component is OK
8263 if not Known_Component_Bit_Offset (C)
8264 or else Component_Bit_Offset (C) < Uint_0
8265 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
8270 -- Check alignment of record type is OK
8272 if not Known_Alignment (Rec)
8273 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8278 -- All tests passed, component is addressable
8283 --------------------------
8284 -- Reason_Bad_Component --
8285 --------------------------
8287 procedure Reason_Bad_Component (C : Entity_Id) is
8288 Rec : constant Entity_Id := Scope (C);
8289 Ctyp : constant Entity_Id := Etype (C);
8292 -- If component clause present assume that's the problem
8294 if Present (Component_Clause (C)) then
8295 Error_Msg_Sloc := Sloc (Component_Clause (C));
8296 Error_Msg_N ("\because of Component_Clause#", N);
8300 -- If pragma Pack clause present, assume that's the problem
8302 if Is_Packed (Rec) then
8303 P := Get_Rep_Pragma (Rec, Name_Pack);
8306 Error_Msg_Sloc := Sloc (P);
8307 Error_Msg_N ("\because of pragma Pack#", N);
8312 -- See if record has bad alignment clause
8314 if Has_Alignment_Clause (Rec)
8315 and then Known_Alignment (Rec)
8316 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8318 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
8321 Error_Msg_Sloc := Sloc (P);
8322 Error_Msg_N ("\because of Alignment clause#", N);
8326 -- Couldn't find a reason, so return without a message
8329 end Reason_Bad_Component;
8331 -- Start of processing for Validate_Independence
8334 for J in Independence_Checks.First .. Independence_Checks.Last loop
8335 N := Independence_Checks.Table (J).N;
8336 E := Independence_Checks.Table (J).E;
8337 IC := Pragma_Name (N) = Name_Independent_Components;
8339 -- Deal with component case
8341 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
8342 if not OK_Component (E) then
8344 Reason_Bad_Component (E);
8349 -- Deal with record with Independent_Components
8351 if IC and then Is_Record_Type (E) then
8352 Comp := First_Component_Or_Discriminant (E);
8353 while Present (Comp) loop
8354 if not OK_Component (Comp) then
8356 Reason_Bad_Component (Comp);
8360 Next_Component_Or_Discriminant (Comp);
8364 -- Deal with address clause case
8366 if Is_Object (E) then
8367 Addr := Address_Clause (E);
8369 if Present (Addr) then
8371 Error_Msg_Sloc := Sloc (Addr);
8372 Error_Msg_N ("\because of Address clause#", N);
8377 -- Deal with independent components for array type
8379 if IC and then Is_Array_Type (E) then
8380 Check_Array_Type (E);
8383 -- Deal with independent components for array object
8385 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
8386 Check_Array_Type (Etype (E));
8391 end Validate_Independence;
8393 -----------------------------------
8394 -- Validate_Unchecked_Conversion --
8395 -----------------------------------
8397 procedure Validate_Unchecked_Conversion
8399 Act_Unit : Entity_Id)
8406 -- Obtain source and target types. Note that we call Ancestor_Subtype
8407 -- here because the processing for generic instantiation always makes
8408 -- subtypes, and we want the original frozen actual types.
8410 -- If we are dealing with private types, then do the check on their
8411 -- fully declared counterparts if the full declarations have been
8412 -- encountered (they don't have to be visible, but they must exist!)
8414 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
8416 if Is_Private_Type (Source)
8417 and then Present (Underlying_Type (Source))
8419 Source := Underlying_Type (Source);
8422 Target := Ancestor_Subtype (Etype (Act_Unit));
8424 -- If either type is generic, the instantiation happens within a generic
8425 -- unit, and there is nothing to check. The proper check
8426 -- will happen when the enclosing generic is instantiated.
8428 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
8432 if Is_Private_Type (Target)
8433 and then Present (Underlying_Type (Target))
8435 Target := Underlying_Type (Target);
8438 -- Source may be unconstrained array, but not target
8440 if Is_Array_Type (Target)
8441 and then not Is_Constrained (Target)
8444 ("unchecked conversion to unconstrained array not allowed", N);
8448 -- Warn if conversion between two different convention pointers
8450 if Is_Access_Type (Target)
8451 and then Is_Access_Type (Source)
8452 and then Convention (Target) /= Convention (Source)
8453 and then Warn_On_Unchecked_Conversion
8455 -- Give warnings for subprogram pointers only on most targets. The
8456 -- exception is VMS, where data pointers can have different lengths
8457 -- depending on the pointer convention.
8459 if Is_Access_Subprogram_Type (Target)
8460 or else Is_Access_Subprogram_Type (Source)
8461 or else OpenVMS_On_Target
8464 ("?conversion between pointers with different conventions!", N);
8468 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
8469 -- warning when compiling GNAT-related sources.
8471 if Warn_On_Unchecked_Conversion
8472 and then not In_Predefined_Unit (N)
8473 and then RTU_Loaded (Ada_Calendar)
8475 (Chars (Source) = Name_Time
8477 Chars (Target) = Name_Time)
8479 -- If Ada.Calendar is loaded and the name of one of the operands is
8480 -- Time, there is a good chance that this is Ada.Calendar.Time.
8483 Calendar_Time : constant Entity_Id :=
8484 Full_View (RTE (RO_CA_Time));
8486 pragma Assert (Present (Calendar_Time));
8488 if Source = Calendar_Time
8489 or else Target = Calendar_Time
8492 ("?representation of 'Time values may change between " &
8493 "'G'N'A'T versions", N);
8498 -- Make entry in unchecked conversion table for later processing by
8499 -- Validate_Unchecked_Conversions, which will check sizes and alignments
8500 -- (using values set by the back-end where possible). This is only done
8501 -- if the appropriate warning is active.
8503 if Warn_On_Unchecked_Conversion then
8504 Unchecked_Conversions.Append
8505 (New_Val => UC_Entry'
8510 -- If both sizes are known statically now, then back end annotation
8511 -- is not required to do a proper check but if either size is not
8512 -- known statically, then we need the annotation.
8514 if Known_Static_RM_Size (Source)
8515 and then Known_Static_RM_Size (Target)
8519 Back_Annotate_Rep_Info := True;
8523 -- If unchecked conversion to access type, and access type is declared
8524 -- in the same unit as the unchecked conversion, then set the
8525 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
8528 if Is_Access_Type (Target) and then
8529 In_Same_Source_Unit (Target, N)
8531 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
8534 -- Generate N_Validate_Unchecked_Conversion node for back end in
8535 -- case the back end needs to perform special validation checks.
8537 -- Shouldn't this be in Exp_Ch13, since the check only gets done
8538 -- if we have full expansion and the back end is called ???
8541 Make_Validate_Unchecked_Conversion (Sloc (N));
8542 Set_Source_Type (Vnode, Source);
8543 Set_Target_Type (Vnode, Target);
8545 -- If the unchecked conversion node is in a list, just insert before it.
8546 -- If not we have some strange case, not worth bothering about.
8548 if Is_List_Member (N) then
8549 Insert_After (N, Vnode);
8551 end Validate_Unchecked_Conversion;
8553 ------------------------------------
8554 -- Validate_Unchecked_Conversions --
8555 ------------------------------------
8557 procedure Validate_Unchecked_Conversions is
8559 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8561 T : UC_Entry renames Unchecked_Conversions.Table (N);
8563 Eloc : constant Source_Ptr := T.Eloc;
8564 Source : constant Entity_Id := T.Source;
8565 Target : constant Entity_Id := T.Target;
8571 -- This validation check, which warns if we have unequal sizes for
8572 -- unchecked conversion, and thus potentially implementation
8573 -- dependent semantics, is one of the few occasions on which we
8574 -- use the official RM size instead of Esize. See description in
8575 -- Einfo "Handling of Type'Size Values" for details.
8577 if Serious_Errors_Detected = 0
8578 and then Known_Static_RM_Size (Source)
8579 and then Known_Static_RM_Size (Target)
8581 -- Don't do the check if warnings off for either type, note the
8582 -- deliberate use of OR here instead of OR ELSE to get the flag
8583 -- Warnings_Off_Used set for both types if appropriate.
8585 and then not (Has_Warnings_Off (Source)
8587 Has_Warnings_Off (Target))
8589 Source_Siz := RM_Size (Source);
8590 Target_Siz := RM_Size (Target);
8592 if Source_Siz /= Target_Siz then
8594 ("?types for unchecked conversion have different sizes!",
8597 if All_Errors_Mode then
8598 Error_Msg_Name_1 := Chars (Source);
8599 Error_Msg_Uint_1 := Source_Siz;
8600 Error_Msg_Name_2 := Chars (Target);
8601 Error_Msg_Uint_2 := Target_Siz;
8602 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8604 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8606 if Is_Discrete_Type (Source)
8607 and then Is_Discrete_Type (Target)
8609 if Source_Siz > Target_Siz then
8611 ("\?^ high order bits of source will be ignored!",
8614 elsif Is_Unsigned_Type (Source) then
8616 ("\?source will be extended with ^ high order " &
8617 "zero bits?!", Eloc);
8621 ("\?source will be extended with ^ high order " &
8626 elsif Source_Siz < Target_Siz then
8627 if Is_Discrete_Type (Target) then
8628 if Bytes_Big_Endian then
8630 ("\?target value will include ^ undefined " &
8635 ("\?target value will include ^ undefined " &
8642 ("\?^ trailing bits of target value will be " &
8643 "undefined!", Eloc);
8646 else pragma Assert (Source_Siz > Target_Siz);
8648 ("\?^ trailing bits of source will be ignored!",
8655 -- If both types are access types, we need to check the alignment.
8656 -- If the alignment of both is specified, we can do it here.
8658 if Serious_Errors_Detected = 0
8659 and then Ekind (Source) in Access_Kind
8660 and then Ekind (Target) in Access_Kind
8661 and then Target_Strict_Alignment
8662 and then Present (Designated_Type (Source))
8663 and then Present (Designated_Type (Target))
8666 D_Source : constant Entity_Id := Designated_Type (Source);
8667 D_Target : constant Entity_Id := Designated_Type (Target);
8670 if Known_Alignment (D_Source)
8671 and then Known_Alignment (D_Target)
8674 Source_Align : constant Uint := Alignment (D_Source);
8675 Target_Align : constant Uint := Alignment (D_Target);
8678 if Source_Align < Target_Align
8679 and then not Is_Tagged_Type (D_Source)
8681 -- Suppress warning if warnings suppressed on either
8682 -- type or either designated type. Note the use of
8683 -- OR here instead of OR ELSE. That is intentional,
8684 -- we would like to set flag Warnings_Off_Used in
8685 -- all types for which warnings are suppressed.
8687 and then not (Has_Warnings_Off (D_Source)
8689 Has_Warnings_Off (D_Target)
8691 Has_Warnings_Off (Source)
8693 Has_Warnings_Off (Target))
8695 Error_Msg_Uint_1 := Target_Align;
8696 Error_Msg_Uint_2 := Source_Align;
8697 Error_Msg_Node_1 := D_Target;
8698 Error_Msg_Node_2 := D_Source;
8700 ("?alignment of & (^) is stricter than " &
8701 "alignment of & (^)!", Eloc);
8703 ("\?resulting access value may have invalid " &
8704 "alignment!", Eloc);
8712 end Validate_Unchecked_Conversions;
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