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 |
1030 Aspect_Storage_Pool |
1031 Aspect_Storage_Size |
1032 Aspect_Stream_Size |
1036 -- Construct the attribute definition clause
1039 Make_Attribute_Definition_Clause (Loc,
1041 Chars => Chars (Id),
1042 Expression => Relocate_Node (Expr));
1044 -- A delay is required except in the common case where
1045 -- the expression is a literal, in which case it is fine
1046 -- to take care of it right away.
1048 if Nkind_In (Expr, N_Integer_Literal, N_String_Literal) then
1049 Delay_Required := False;
1051 Delay_Required := True;
1052 Set_Is_Delayed_Aspect (Aspect);
1055 -- Aspects corresponding to pragmas with two arguments, where
1056 -- the first argument is a local name referring to the entity,
1057 -- and the second argument is the aspect definition expression
1058 -- which is an expression that does not get analyzed.
1060 when Aspect_Suppress |
1061 Aspect_Unsuppress =>
1063 -- Construct the pragma
1067 Pragma_Argument_Associations => New_List (
1068 New_Occurrence_Of (E, Loc),
1069 Relocate_Node (Expr)),
1070 Pragma_Identifier =>
1071 Make_Identifier (Sloc (Id), Chars (Id)));
1073 -- We don't have to play the delay game here, since the only
1074 -- values are check names which don't get analyzed anyway.
1076 Delay_Required := False;
1078 -- Aspects corresponding to pragmas with two arguments, where
1079 -- the second argument is a local name referring to the entity,
1080 -- and the first argument is the aspect definition expression.
1082 when Aspect_Warnings =>
1084 -- Construct the pragma
1088 Pragma_Argument_Associations => New_List (
1089 Relocate_Node (Expr),
1090 New_Occurrence_Of (E, Loc)),
1091 Pragma_Identifier =>
1092 Make_Identifier (Sloc (Id), Chars (Id)),
1093 Class_Present => Class_Present (Aspect));
1095 -- We don't have to play the delay game here, since the only
1096 -- values are ON/OFF which don't get analyzed anyway.
1098 Delay_Required := False;
1100 -- Default_Value and Default_Component_Value aspects. These
1101 -- are specially handled because they have no corresponding
1102 -- pragmas or attributes.
1104 when Aspect_Default_Value | Aspect_Default_Component_Value =>
1105 Error_Msg_Name_1 := Chars (Id);
1107 if not Is_Type (E) then
1108 Error_Msg_N ("aspect% can only apply to a type", Id);
1111 elsif not Is_First_Subtype (E) then
1112 Error_Msg_N ("aspect% cannot apply to subtype", Id);
1115 elsif A_Id = Aspect_Default_Value
1116 and then not Is_Scalar_Type (E)
1119 ("aspect% can only be applied to scalar type", Id);
1122 elsif A_Id = Aspect_Default_Component_Value then
1123 if not Is_Array_Type (E) then
1125 ("aspect% can only be applied to array type", Id);
1127 elsif not Is_Scalar_Type (Component_Type (E)) then
1129 ("aspect% requires scalar components", Id);
1135 Delay_Required := True;
1136 Set_Is_Delayed_Aspect (Aspect);
1137 Set_Has_Default_Aspect (Base_Type (Entity (Ent)));
1139 when Aspect_Attach_Handler =>
1142 Pragma_Identifier =>
1143 Make_Identifier (Sloc (Id), Name_Attach_Handler),
1144 Pragma_Argument_Associations =>
1145 New_List (Ent, Relocate_Node (Expr)));
1147 Set_From_Aspect_Specification (Aitem, True);
1149 when Aspect_Priority | Aspect_Interrupt_Priority => declare
1153 if A_Id = Aspect_Priority then
1154 Pname := Name_Priority;
1156 Pname := Name_Interrupt_Priority;
1161 Pragma_Identifier =>
1162 Make_Identifier (Sloc (Id), Pname),
1163 Pragma_Argument_Associations =>
1164 New_List (Relocate_Node (Expr)));
1166 Set_From_Aspect_Specification (Aitem, True);
1169 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
1170 -- with a first argument that is the expression, and a second
1171 -- argument that is an informative message if the test fails.
1172 -- This is inserted right after the declaration, to get the
1173 -- required pragma placement. The processing for the pragmas
1174 -- takes care of the required delay.
1176 when Pre_Post_Aspects => declare
1180 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
1181 Pname := Name_Precondition;
1183 Pname := Name_Postcondition;
1186 -- If the expressions is of the form A and then B, then
1187 -- we generate separate Pre/Post aspects for the separate
1188 -- clauses. Since we allow multiple pragmas, there is no
1189 -- problem in allowing multiple Pre/Post aspects internally.
1190 -- These should be treated in reverse order (B first and
1191 -- A second) since they are later inserted just after N in
1192 -- the order they are treated. This way, the pragma for A
1193 -- ends up preceding the pragma for B, which may have an
1194 -- importance for the error raised (either constraint error
1195 -- or precondition error).
1197 -- We do not do this for Pre'Class, since we have to put
1198 -- these conditions together in a complex OR expression
1200 if Pname = Name_Postcondition
1201 or else not Class_Present (Aspect)
1203 while Nkind (Expr) = N_And_Then loop
1204 Insert_After (Aspect,
1205 Make_Aspect_Specification (Sloc (Left_Opnd (Expr)),
1206 Identifier => Identifier (Aspect),
1207 Expression => Relocate_Node (Left_Opnd (Expr)),
1208 Class_Present => Class_Present (Aspect),
1209 Split_PPC => True));
1210 Rewrite (Expr, Relocate_Node (Right_Opnd (Expr)));
1211 Eloc := Sloc (Expr);
1215 -- Build the precondition/postcondition pragma
1219 Pragma_Identifier =>
1220 Make_Identifier (Sloc (Id), Pname),
1221 Class_Present => Class_Present (Aspect),
1222 Split_PPC => Split_PPC (Aspect),
1223 Pragma_Argument_Associations => New_List (
1224 Make_Pragma_Argument_Association (Eloc,
1225 Chars => Name_Check,
1226 Expression => Relocate_Node (Expr))));
1228 -- Add message unless exception messages are suppressed
1230 if not Opt.Exception_Locations_Suppressed then
1231 Append_To (Pragma_Argument_Associations (Aitem),
1232 Make_Pragma_Argument_Association (Eloc,
1233 Chars => Name_Message,
1235 Make_String_Literal (Eloc,
1237 & Get_Name_String (Pname)
1239 & Build_Location_String (Eloc))));
1242 Set_From_Aspect_Specification (Aitem, True);
1243 Set_Is_Delayed_Aspect (Aspect);
1245 -- For Pre/Post cases, insert immediately after the entity
1246 -- declaration, since that is the required pragma placement.
1247 -- Note that for these aspects, we do not have to worry
1248 -- about delay issues, since the pragmas themselves deal
1249 -- with delay of visibility for the expression analysis.
1251 -- If the entity is a library-level subprogram, the pre/
1252 -- postconditions must be treated as late pragmas.
1254 if Nkind (Parent (N)) = N_Compilation_Unit then
1255 Add_Global_Declaration (Aitem);
1257 Insert_After (N, Aitem);
1263 -- Invariant aspects generate a corresponding pragma with a
1264 -- first argument that is the entity, a second argument that is
1265 -- the expression and a third argument that is an appropriate
1266 -- message. This is inserted right after the declaration, to
1267 -- get the required pragma placement. The pragma processing
1268 -- takes care of the required delay.
1270 when Aspect_Invariant |
1271 Aspect_Type_Invariant =>
1273 -- Check placement legality
1275 if not Nkind_In (N, N_Private_Type_Declaration,
1276 N_Private_Extension_Declaration)
1279 ("invariant aspect must apply to a private type", N);
1282 -- Construct the pragma
1286 Pragma_Argument_Associations =>
1287 New_List (Ent, Relocate_Node (Expr)),
1288 Class_Present => Class_Present (Aspect),
1289 Pragma_Identifier =>
1290 Make_Identifier (Sloc (Id), Name_Invariant));
1292 -- Add message unless exception messages are suppressed
1294 if not Opt.Exception_Locations_Suppressed then
1295 Append_To (Pragma_Argument_Associations (Aitem),
1296 Make_Pragma_Argument_Association (Eloc,
1297 Chars => Name_Message,
1299 Make_String_Literal (Eloc,
1300 Strval => "failed invariant from "
1301 & Build_Location_String (Eloc))));
1304 Set_From_Aspect_Specification (Aitem, True);
1305 Set_Is_Delayed_Aspect (Aspect);
1307 -- For Invariant case, insert immediately after the entity
1308 -- declaration. We do not have to worry about delay issues
1309 -- since the pragma processing takes care of this.
1311 Insert_After (N, Aitem);
1314 -- Predicate aspects generate a corresponding pragma with a
1315 -- first argument that is the entity, and the second argument
1316 -- is the expression.
1318 when Aspect_Dynamic_Predicate |
1320 Aspect_Static_Predicate =>
1322 -- Construct the pragma (always a pragma Predicate, with
1323 -- flags recording whether it is static/dynamic).
1327 Pragma_Argument_Associations =>
1328 New_List (Ent, Relocate_Node (Expr)),
1329 Class_Present => Class_Present (Aspect),
1330 Pragma_Identifier =>
1331 Make_Identifier (Sloc (Id), Name_Predicate));
1333 Set_From_Aspect_Specification (Aitem, True);
1335 -- Set special flags for dynamic/static cases
1337 if A_Id = Aspect_Dynamic_Predicate then
1338 Set_From_Dynamic_Predicate (Aitem);
1339 elsif A_Id = Aspect_Static_Predicate then
1340 Set_From_Static_Predicate (Aitem);
1343 -- Make sure we have a freeze node (it might otherwise be
1344 -- missing in cases like subtype X is Y, and we would not
1345 -- have a place to build the predicate function).
1347 Set_Has_Predicates (E);
1349 if Is_Private_Type (E)
1350 and then Present (Full_View (E))
1352 Set_Has_Predicates (Full_View (E));
1353 Set_Has_Delayed_Aspects (Full_View (E));
1356 Ensure_Freeze_Node (E);
1357 Set_Is_Delayed_Aspect (Aspect);
1358 Delay_Required := True;
1360 when Aspect_Test_Case => declare
1362 Comp_Expr : Node_Id;
1363 Comp_Assn : Node_Id;
1368 if Nkind (Expr) /= N_Aggregate then
1370 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1374 Comp_Expr := First (Expressions (Expr));
1375 while Present (Comp_Expr) loop
1376 Append (Relocate_Node (Comp_Expr), Args);
1380 Comp_Assn := First (Component_Associations (Expr));
1381 while Present (Comp_Assn) loop
1382 if List_Length (Choices (Comp_Assn)) /= 1
1384 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
1387 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1391 Append (Make_Pragma_Argument_Association (
1392 Sloc => Sloc (Comp_Assn),
1393 Chars => Chars (First (Choices (Comp_Assn))),
1394 Expression => Relocate_Node (Expression (Comp_Assn))),
1399 -- Build the test-case pragma
1403 Pragma_Identifier =>
1404 Make_Identifier (Sloc (Id), Name_Test_Case),
1405 Pragma_Argument_Associations =>
1408 Set_From_Aspect_Specification (Aitem, True);
1409 Set_Is_Delayed_Aspect (Aspect);
1411 -- Insert immediately after the entity declaration
1413 Insert_After (N, Aitem);
1419 -- If a delay is required, we delay the freeze (not much point in
1420 -- delaying the aspect if we don't delay the freeze!). The pragma
1421 -- or attribute clause if there is one is then attached to the
1422 -- aspect specification which is placed in the rep item list.
1424 if Delay_Required then
1425 if Present (Aitem) then
1426 Set_From_Aspect_Specification (Aitem, True);
1427 Set_Is_Delayed_Aspect (Aitem);
1428 Set_Aspect_Rep_Item (Aspect, Aitem);
1431 Ensure_Freeze_Node (E);
1432 Set_Has_Delayed_Aspects (E);
1433 Record_Rep_Item (E, Aspect);
1435 -- If no delay required, insert the pragma/clause in the tree
1438 Set_From_Aspect_Specification (Aitem, True);
1440 -- If this is a compilation unit, we will put the pragma in
1441 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1443 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1445 Aux : constant Node_Id :=
1446 Aux_Decls_Node (Parent (Ins_Node));
1449 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1451 if No (Pragmas_After (Aux)) then
1452 Set_Pragmas_After (Aux, Empty_List);
1455 -- For Pre_Post put at start of list, otherwise at end
1457 if A_Id in Pre_Post_Aspects then
1458 Prepend (Aitem, Pragmas_After (Aux));
1460 Append (Aitem, Pragmas_After (Aux));
1464 -- Here if not compilation unit case
1468 -- For Pre/Post cases, insert immediately after the
1469 -- entity declaration, since that is the required pragma
1472 when Pre_Post_Aspects =>
1473 Insert_After (N, Aitem);
1475 -- For Priority aspects, insert into the task or
1476 -- protected definition, which we need to create if it's
1479 when Aspect_Priority | Aspect_Interrupt_Priority =>
1481 T : Node_Id; -- the type declaration
1482 L : List_Id; -- list of decls of task/protected
1485 if Nkind (N) = N_Object_Declaration then
1486 T := Parent (Etype (Defining_Identifier (N)));
1492 if Nkind (T) = N_Protected_Type_Declaration then
1494 (Present (Protected_Definition (T)));
1496 L := Visible_Declarations
1497 (Protected_Definition (T));
1499 elsif Nkind (T) = N_Task_Type_Declaration then
1500 if No (Task_Definition (T)) then
1503 Make_Task_Definition
1505 Visible_Declarations => New_List,
1506 End_Label => Empty));
1509 L := Visible_Declarations
1510 (Task_Definition (T));
1513 raise Program_Error;
1516 Prepend (Aitem, To => L);
1519 -- For all other cases, insert in sequence
1522 Insert_After (Ins_Node, Aitem);
1531 end loop Aspect_Loop;
1532 end Analyze_Aspect_Specifications;
1534 -----------------------
1535 -- Analyze_At_Clause --
1536 -----------------------
1538 -- An at clause is replaced by the corresponding Address attribute
1539 -- definition clause that is the preferred approach in Ada 95.
1541 procedure Analyze_At_Clause (N : Node_Id) is
1542 CS : constant Boolean := Comes_From_Source (N);
1545 -- This is an obsolescent feature
1547 Check_Restriction (No_Obsolescent_Features, N);
1549 if Warn_On_Obsolescent_Feature then
1551 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1553 ("\use address attribute definition clause instead?", N);
1556 -- Rewrite as address clause
1559 Make_Attribute_Definition_Clause (Sloc (N),
1560 Name => Identifier (N),
1561 Chars => Name_Address,
1562 Expression => Expression (N)));
1564 -- We preserve Comes_From_Source, since logically the clause still
1565 -- comes from the source program even though it is changed in form.
1567 Set_Comes_From_Source (N, CS);
1569 -- Analyze rewritten clause
1571 Analyze_Attribute_Definition_Clause (N);
1572 end Analyze_At_Clause;
1574 -----------------------------------------
1575 -- Analyze_Attribute_Definition_Clause --
1576 -----------------------------------------
1578 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1579 Loc : constant Source_Ptr := Sloc (N);
1580 Nam : constant Node_Id := Name (N);
1581 Attr : constant Name_Id := Chars (N);
1582 Expr : constant Node_Id := Expression (N);
1583 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1586 -- The entity of Nam after it is analyzed. In the case of an incomplete
1587 -- type, this is the underlying type.
1590 -- The underlying entity to which the attribute applies. Generally this
1591 -- is the Underlying_Type of Ent, except in the case where the clause
1592 -- applies to full view of incomplete type or private type in which case
1593 -- U_Ent is just a copy of Ent.
1595 FOnly : Boolean := False;
1596 -- Reset to True for subtype specific attribute (Alignment, Size)
1597 -- and for stream attributes, i.e. those cases where in the call
1598 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1599 -- rules are checked. Note that the case of stream attributes is not
1600 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1601 -- disallow Storage_Size for derived task types, but that is also
1602 -- clearly unintentional.
1604 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1605 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1606 -- definition clauses.
1608 function Duplicate_Clause return Boolean;
1609 -- This routine checks if the aspect for U_Ent being given by attribute
1610 -- definition clause N is for an aspect that has already been specified,
1611 -- and if so gives an error message. If there is a duplicate, True is
1612 -- returned, otherwise if there is no error, False is returned.
1614 procedure Check_Indexing_Functions;
1615 -- Check that the function in Constant_Indexing or Variable_Indexing
1616 -- attribute has the proper type structure. If the name is overloaded,
1617 -- check that all interpretations are legal.
1619 procedure Check_Iterator_Functions;
1620 -- Check that there is a single function in Default_Iterator attribute
1621 -- has the proper type structure.
1623 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
1624 -- Common legality check for the previous two
1626 -----------------------------------
1627 -- Analyze_Stream_TSS_Definition --
1628 -----------------------------------
1630 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1631 Subp : Entity_Id := Empty;
1636 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1637 -- True for Read attribute, false for other attributes
1639 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1640 -- Return true if the entity is a subprogram with an appropriate
1641 -- profile for the attribute being defined.
1643 ----------------------
1644 -- Has_Good_Profile --
1645 ----------------------
1647 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1649 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1650 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1651 (False => E_Procedure, True => E_Function);
1655 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1659 F := First_Formal (Subp);
1662 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1663 or else Designated_Type (Etype (F)) /=
1664 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1669 if not Is_Function then
1673 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1674 (False => E_In_Parameter,
1675 True => E_Out_Parameter);
1677 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1685 Typ := Etype (Subp);
1688 return Base_Type (Typ) = Base_Type (Ent)
1689 and then No (Next_Formal (F));
1690 end Has_Good_Profile;
1692 -- Start of processing for Analyze_Stream_TSS_Definition
1697 if not Is_Type (U_Ent) then
1698 Error_Msg_N ("local name must be a subtype", Nam);
1702 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1704 -- If Pnam is present, it can be either inherited from an ancestor
1705 -- type (in which case it is legal to redefine it for this type), or
1706 -- be a previous definition of the attribute for the same type (in
1707 -- which case it is illegal).
1709 -- In the first case, it will have been analyzed already, and we
1710 -- can check that its profile does not match the expected profile
1711 -- for a stream attribute of U_Ent. In the second case, either Pnam
1712 -- has been analyzed (and has the expected profile), or it has not
1713 -- been analyzed yet (case of a type that has not been frozen yet
1714 -- and for which the stream attribute has been set using Set_TSS).
1717 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1719 Error_Msg_Sloc := Sloc (Pnam);
1720 Error_Msg_Name_1 := Attr;
1721 Error_Msg_N ("% attribute already defined #", Nam);
1727 if Is_Entity_Name (Expr) then
1728 if not Is_Overloaded (Expr) then
1729 if Has_Good_Profile (Entity (Expr)) then
1730 Subp := Entity (Expr);
1734 Get_First_Interp (Expr, I, It);
1735 while Present (It.Nam) loop
1736 if Has_Good_Profile (It.Nam) then
1741 Get_Next_Interp (I, It);
1746 if Present (Subp) then
1747 if Is_Abstract_Subprogram (Subp) then
1748 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1752 Set_Entity (Expr, Subp);
1753 Set_Etype (Expr, Etype (Subp));
1755 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1758 Error_Msg_Name_1 := Attr;
1759 Error_Msg_N ("incorrect expression for% attribute", Expr);
1761 end Analyze_Stream_TSS_Definition;
1763 ------------------------------
1764 -- Check_Indexing_Functions --
1765 ------------------------------
1767 procedure Check_Indexing_Functions is
1769 procedure Check_One_Function (Subp : Entity_Id);
1770 -- Check one possible interpretation
1772 ------------------------
1773 -- Check_One_Function --
1774 ------------------------
1776 procedure Check_One_Function (Subp : Entity_Id) is
1778 if not Check_Primitive_Function (Subp) then
1780 ("aspect Indexing requires a function that applies to type&",
1784 if not Has_Implicit_Dereference (Etype (Subp)) then
1786 ("function for indexing must return a reference type", Subp);
1788 end Check_One_Function;
1790 -- Start of processing for Check_Indexing_Functions
1799 if not Is_Overloaded (Expr) then
1800 Check_One_Function (Entity (Expr));
1808 Get_First_Interp (Expr, I, It);
1809 while Present (It.Nam) loop
1811 -- Note that analysis will have added the interpretation
1812 -- that corresponds to the dereference. We only check the
1813 -- subprogram itself.
1815 if Is_Overloadable (It.Nam) then
1816 Check_One_Function (It.Nam);
1819 Get_Next_Interp (I, It);
1823 end Check_Indexing_Functions;
1825 ------------------------------
1826 -- Check_Iterator_Functions --
1827 ------------------------------
1829 procedure Check_Iterator_Functions is
1830 Default : Entity_Id;
1832 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
1833 -- Check one possible interpretation for validity
1835 ----------------------------
1836 -- Valid_Default_Iterator --
1837 ----------------------------
1839 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
1843 if not Check_Primitive_Function (Subp) then
1846 Formal := First_Formal (Subp);
1849 -- False if any subsequent formal has no default expression
1851 Formal := Next_Formal (Formal);
1852 while Present (Formal) loop
1853 if No (Expression (Parent (Formal))) then
1857 Next_Formal (Formal);
1860 -- True if all subsequent formals have default expressions
1863 end Valid_Default_Iterator;
1865 -- Start of processing for Check_Iterator_Functions
1870 if not Is_Entity_Name (Expr) then
1871 Error_Msg_N ("aspect Iterator must be a function name", Expr);
1874 if not Is_Overloaded (Expr) then
1875 if not Check_Primitive_Function (Entity (Expr)) then
1877 ("aspect Indexing requires a function that applies to type&",
1878 Entity (Expr), Ent);
1881 if not Valid_Default_Iterator (Entity (Expr)) then
1882 Error_Msg_N ("improper function for default iterator", Expr);
1892 Get_First_Interp (Expr, I, It);
1893 while Present (It.Nam) loop
1894 if not Check_Primitive_Function (It.Nam)
1895 or else Valid_Default_Iterator (It.Nam)
1899 elsif Present (Default) then
1900 Error_Msg_N ("default iterator must be unique", Expr);
1906 Get_Next_Interp (I, It);
1910 if Present (Default) then
1911 Set_Entity (Expr, Default);
1912 Set_Is_Overloaded (Expr, False);
1915 end Check_Iterator_Functions;
1917 -------------------------------
1918 -- Check_Primitive_Function --
1919 -------------------------------
1921 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
1925 if Ekind (Subp) /= E_Function then
1929 if No (First_Formal (Subp)) then
1932 Ctrl := Etype (First_Formal (Subp));
1936 or else Ctrl = Class_Wide_Type (Ent)
1938 (Ekind (Ctrl) = E_Anonymous_Access_Type
1940 (Designated_Type (Ctrl) = Ent
1941 or else Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
1950 end Check_Primitive_Function;
1952 ----------------------
1953 -- Duplicate_Clause --
1954 ----------------------
1956 function Duplicate_Clause return Boolean is
1960 -- Nothing to do if this attribute definition clause comes from
1961 -- an aspect specification, since we could not be duplicating an
1962 -- explicit clause, and we dealt with the case of duplicated aspects
1963 -- in Analyze_Aspect_Specifications.
1965 if From_Aspect_Specification (N) then
1969 -- Otherwise current clause may duplicate previous clause or a
1970 -- previously given aspect specification for the same aspect.
1972 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
1975 if Entity (A) = U_Ent then
1976 Error_Msg_Name_1 := Chars (N);
1977 Error_Msg_Sloc := Sloc (A);
1978 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
1984 end Duplicate_Clause;
1986 -- Start of processing for Analyze_Attribute_Definition_Clause
1989 -- The following code is a defense against recursion. Not clear that
1990 -- this can happen legitimately, but perhaps some error situations
1991 -- can cause it, and we did see this recursion during testing.
1993 if Analyzed (N) then
1996 Set_Analyzed (N, True);
1999 -- Process Ignore_Rep_Clauses option (we also ignore rep clauses in
2000 -- CodePeer mode, since they are not relevant in that context).
2002 if Ignore_Rep_Clauses or CodePeer_Mode then
2005 -- The following should be ignored. They do not affect legality
2006 -- and may be target dependent. The basic idea of -gnatI is to
2007 -- ignore any rep clauses that may be target dependent but do not
2008 -- affect legality (except possibly to be rejected because they
2009 -- are incompatible with the compilation target).
2011 when Attribute_Alignment |
2012 Attribute_Bit_Order |
2013 Attribute_Component_Size |
2014 Attribute_Machine_Radix |
2015 Attribute_Object_Size |
2017 Attribute_Stream_Size |
2018 Attribute_Value_Size =>
2019 Rewrite (N, Make_Null_Statement (Sloc (N)));
2022 -- We do not want too ignore 'Small in CodePeer_Mode, since it
2023 -- has an impact on the exact computations performed.
2025 -- Perhaps 'Small should also not be ignored by
2026 -- Ignore_Rep_Clauses ???
2028 when Attribute_Small =>
2029 if Ignore_Rep_Clauses then
2030 Rewrite (N, Make_Null_Statement (Sloc (N)));
2034 -- The following should not be ignored, because in the first place
2035 -- they are reasonably portable, and should not cause problems in
2036 -- compiling code from another target, and also they do affect
2037 -- legality, e.g. failing to provide a stream attribute for a
2038 -- type may make a program illegal.
2040 when Attribute_External_Tag |
2044 Attribute_Storage_Pool |
2045 Attribute_Storage_Size |
2049 -- Other cases are errors ("attribute& cannot be set with
2050 -- definition clause"), which will be caught below.
2058 Ent := Entity (Nam);
2060 if Rep_Item_Too_Early (Ent, N) then
2064 -- Rep clause applies to full view of incomplete type or private type if
2065 -- we have one (if not, this is a premature use of the type). However,
2066 -- certain semantic checks need to be done on the specified entity (i.e.
2067 -- the private view), so we save it in Ent.
2069 if Is_Private_Type (Ent)
2070 and then Is_Derived_Type (Ent)
2071 and then not Is_Tagged_Type (Ent)
2072 and then No (Full_View (Ent))
2074 -- If this is a private type whose completion is a derivation from
2075 -- another private type, there is no full view, and the attribute
2076 -- belongs to the type itself, not its underlying parent.
2080 elsif Ekind (Ent) = E_Incomplete_Type then
2082 -- The attribute applies to the full view, set the entity of the
2083 -- attribute definition accordingly.
2085 Ent := Underlying_Type (Ent);
2087 Set_Entity (Nam, Ent);
2090 U_Ent := Underlying_Type (Ent);
2093 -- Complete other routine error checks
2095 if Etype (Nam) = Any_Type then
2098 elsif Scope (Ent) /= Current_Scope then
2099 Error_Msg_N ("entity must be declared in this scope", Nam);
2102 elsif No (U_Ent) then
2105 elsif Is_Type (U_Ent)
2106 and then not Is_First_Subtype (U_Ent)
2107 and then Id /= Attribute_Object_Size
2108 and then Id /= Attribute_Value_Size
2109 and then not From_At_Mod (N)
2111 Error_Msg_N ("cannot specify attribute for subtype", Nam);
2115 Set_Entity (N, U_Ent);
2117 -- Switch on particular attribute
2125 -- Address attribute definition clause
2127 when Attribute_Address => Address : begin
2129 -- A little error check, catch for X'Address use X'Address;
2131 if Nkind (Nam) = N_Identifier
2132 and then Nkind (Expr) = N_Attribute_Reference
2133 and then Attribute_Name (Expr) = Name_Address
2134 and then Nkind (Prefix (Expr)) = N_Identifier
2135 and then Chars (Nam) = Chars (Prefix (Expr))
2138 ("address for & is self-referencing", Prefix (Expr), Ent);
2142 -- Not that special case, carry on with analysis of expression
2144 Analyze_And_Resolve (Expr, RTE (RE_Address));
2146 -- Even when ignoring rep clauses we need to indicate that the
2147 -- entity has an address clause and thus it is legal to declare
2150 if Ignore_Rep_Clauses then
2151 if Ekind_In (U_Ent, E_Variable, E_Constant) then
2152 Record_Rep_Item (U_Ent, N);
2158 if Duplicate_Clause then
2161 -- Case of address clause for subprogram
2163 elsif Is_Subprogram (U_Ent) then
2164 if Has_Homonym (U_Ent) then
2166 ("address clause cannot be given " &
2167 "for overloaded subprogram",
2172 -- For subprograms, all address clauses are permitted, and we
2173 -- mark the subprogram as having a deferred freeze so that Gigi
2174 -- will not elaborate it too soon.
2176 -- Above needs more comments, what is too soon about???
2178 Set_Has_Delayed_Freeze (U_Ent);
2180 -- Case of address clause for entry
2182 elsif Ekind (U_Ent) = E_Entry then
2183 if Nkind (Parent (N)) = N_Task_Body then
2185 ("entry address must be specified in task spec", Nam);
2189 -- For entries, we require a constant address
2191 Check_Constant_Address_Clause (Expr, U_Ent);
2193 -- Special checks for task types
2195 if Is_Task_Type (Scope (U_Ent))
2196 and then Comes_From_Source (Scope (U_Ent))
2199 ("?entry address declared for entry in task type", N);
2201 ("\?only one task can be declared of this type", N);
2204 -- Entry address clauses are obsolescent
2206 Check_Restriction (No_Obsolescent_Features, N);
2208 if Warn_On_Obsolescent_Feature then
2210 ("attaching interrupt to task entry is an " &
2211 "obsolescent feature (RM J.7.1)?", N);
2213 ("\use interrupt procedure instead?", N);
2216 -- Case of an address clause for a controlled object which we
2217 -- consider to be erroneous.
2219 elsif Is_Controlled (Etype (U_Ent))
2220 or else Has_Controlled_Component (Etype (U_Ent))
2223 ("?controlled object& must not be overlaid", Nam, U_Ent);
2225 ("\?Program_Error will be raised at run time", Nam);
2226 Insert_Action (Declaration_Node (U_Ent),
2227 Make_Raise_Program_Error (Loc,
2228 Reason => PE_Overlaid_Controlled_Object));
2231 -- Case of address clause for a (non-controlled) object
2234 Ekind (U_Ent) = E_Variable
2236 Ekind (U_Ent) = E_Constant
2239 Expr : constant Node_Id := Expression (N);
2244 -- Exported variables cannot have an address clause, because
2245 -- this cancels the effect of the pragma Export.
2247 if Is_Exported (U_Ent) then
2249 ("cannot export object with address clause", Nam);
2253 Find_Overlaid_Entity (N, O_Ent, Off);
2255 -- Overlaying controlled objects is erroneous
2258 and then (Has_Controlled_Component (Etype (O_Ent))
2259 or else Is_Controlled (Etype (O_Ent)))
2262 ("?cannot overlay with controlled object", Expr);
2264 ("\?Program_Error will be raised at run time", Expr);
2265 Insert_Action (Declaration_Node (U_Ent),
2266 Make_Raise_Program_Error (Loc,
2267 Reason => PE_Overlaid_Controlled_Object));
2270 elsif Present (O_Ent)
2271 and then Ekind (U_Ent) = E_Constant
2272 and then not Is_Constant_Object (O_Ent)
2274 Error_Msg_N ("constant overlays a variable?", Expr);
2276 elsif Present (Renamed_Object (U_Ent)) then
2278 ("address clause not allowed"
2279 & " for a renaming declaration (RM 13.1(6))", Nam);
2282 -- Imported variables can have an address clause, but then
2283 -- the import is pretty meaningless except to suppress
2284 -- initializations, so we do not need such variables to
2285 -- be statically allocated (and in fact it causes trouble
2286 -- if the address clause is a local value).
2288 elsif Is_Imported (U_Ent) then
2289 Set_Is_Statically_Allocated (U_Ent, False);
2292 -- We mark a possible modification of a variable with an
2293 -- address clause, since it is likely aliasing is occurring.
2295 Note_Possible_Modification (Nam, Sure => False);
2297 -- Here we are checking for explicit overlap of one variable
2298 -- by another, and if we find this then mark the overlapped
2299 -- variable as also being volatile to prevent unwanted
2300 -- optimizations. This is a significant pessimization so
2301 -- avoid it when there is an offset, i.e. when the object
2302 -- is composite; they cannot be optimized easily anyway.
2305 and then Is_Object (O_Ent)
2308 Set_Treat_As_Volatile (O_Ent);
2311 -- Legality checks on the address clause for initialized
2312 -- objects is deferred until the freeze point, because
2313 -- a subsequent pragma might indicate that the object is
2314 -- imported and thus not initialized.
2316 Set_Has_Delayed_Freeze (U_Ent);
2318 -- If an initialization call has been generated for this
2319 -- object, it needs to be deferred to after the freeze node
2320 -- we have just now added, otherwise GIGI will see a
2321 -- reference to the variable (as actual to the IP call)
2322 -- before its definition.
2325 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
2327 if Present (Init_Call) then
2329 Append_Freeze_Action (U_Ent, Init_Call);
2333 if Is_Exported (U_Ent) then
2335 ("& cannot be exported if an address clause is given",
2338 ("\define and export a variable " &
2339 "that holds its address instead",
2343 -- Entity has delayed freeze, so we will generate an
2344 -- alignment check at the freeze point unless suppressed.
2346 if not Range_Checks_Suppressed (U_Ent)
2347 and then not Alignment_Checks_Suppressed (U_Ent)
2349 Set_Check_Address_Alignment (N);
2352 -- Kill the size check code, since we are not allocating
2353 -- the variable, it is somewhere else.
2355 Kill_Size_Check_Code (U_Ent);
2357 -- If the address clause is of the form:
2359 -- for Y'Address use X'Address
2363 -- Const : constant Address := X'Address;
2365 -- for Y'Address use Const;
2367 -- then we make an entry in the table for checking the size
2368 -- and alignment of the overlaying variable. We defer this
2369 -- check till after code generation to take full advantage
2370 -- of the annotation done by the back end. This entry is
2371 -- only made if the address clause comes from source.
2373 -- If the entity has a generic type, the check will be
2374 -- performed in the instance if the actual type justifies
2375 -- it, and we do not insert the clause in the table to
2376 -- prevent spurious warnings.
2378 if Address_Clause_Overlay_Warnings
2379 and then Comes_From_Source (N)
2380 and then Present (O_Ent)
2381 and then Is_Object (O_Ent)
2383 if not Is_Generic_Type (Etype (U_Ent)) then
2384 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
2387 -- If variable overlays a constant view, and we are
2388 -- warning on overlays, then mark the variable as
2389 -- overlaying a constant (we will give warnings later
2390 -- if this variable is assigned).
2392 if Is_Constant_Object (O_Ent)
2393 and then Ekind (U_Ent) = E_Variable
2395 Set_Overlays_Constant (U_Ent);
2400 -- Not a valid entity for an address clause
2403 Error_Msg_N ("address cannot be given for &", Nam);
2411 -- Alignment attribute definition clause
2413 when Attribute_Alignment => Alignment : declare
2414 Align : constant Uint := Get_Alignment_Value (Expr);
2419 if not Is_Type (U_Ent)
2420 and then Ekind (U_Ent) /= E_Variable
2421 and then Ekind (U_Ent) /= E_Constant
2423 Error_Msg_N ("alignment cannot be given for &", Nam);
2425 elsif Duplicate_Clause then
2428 elsif Align /= No_Uint then
2429 Set_Has_Alignment_Clause (U_Ent);
2430 Set_Alignment (U_Ent, Align);
2432 -- For an array type, U_Ent is the first subtype. In that case,
2433 -- also set the alignment of the anonymous base type so that
2434 -- other subtypes (such as the itypes for aggregates of the
2435 -- type) also receive the expected alignment.
2437 if Is_Array_Type (U_Ent) then
2438 Set_Alignment (Base_Type (U_Ent), Align);
2447 -- Bit_Order attribute definition clause
2449 when Attribute_Bit_Order => Bit_Order : declare
2451 if not Is_Record_Type (U_Ent) then
2453 ("Bit_Order can only be defined for record type", Nam);
2455 elsif Duplicate_Clause then
2459 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
2461 if Etype (Expr) = Any_Type then
2464 elsif not Is_Static_Expression (Expr) then
2465 Flag_Non_Static_Expr
2466 ("Bit_Order requires static expression!", Expr);
2469 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
2470 Set_Reverse_Bit_Order (U_Ent, True);
2476 --------------------
2477 -- Component_Size --
2478 --------------------
2480 -- Component_Size attribute definition clause
2482 when Attribute_Component_Size => Component_Size_Case : declare
2483 Csize : constant Uint := Static_Integer (Expr);
2487 New_Ctyp : Entity_Id;
2491 if not Is_Array_Type (U_Ent) then
2492 Error_Msg_N ("component size requires array type", Nam);
2496 Btype := Base_Type (U_Ent);
2497 Ctyp := Component_Type (Btype);
2499 if Duplicate_Clause then
2502 elsif Rep_Item_Too_Early (Btype, N) then
2505 elsif Csize /= No_Uint then
2506 Check_Size (Expr, Ctyp, Csize, Biased);
2508 -- For the biased case, build a declaration for a subtype that
2509 -- will be used to represent the biased subtype that reflects
2510 -- the biased representation of components. We need the subtype
2511 -- to get proper conversions on referencing elements of the
2512 -- array. Note: component size clauses are ignored in VM mode.
2514 if VM_Target = No_VM then
2517 Make_Defining_Identifier (Loc,
2519 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2522 Make_Subtype_Declaration (Loc,
2523 Defining_Identifier => New_Ctyp,
2524 Subtype_Indication =>
2525 New_Occurrence_Of (Component_Type (Btype), Loc));
2527 Set_Parent (Decl, N);
2528 Analyze (Decl, Suppress => All_Checks);
2530 Set_Has_Delayed_Freeze (New_Ctyp, False);
2531 Set_Esize (New_Ctyp, Csize);
2532 Set_RM_Size (New_Ctyp, Csize);
2533 Init_Alignment (New_Ctyp);
2534 Set_Is_Itype (New_Ctyp, True);
2535 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2537 Set_Component_Type (Btype, New_Ctyp);
2538 Set_Biased (New_Ctyp, N, "component size clause");
2541 Set_Component_Size (Btype, Csize);
2543 -- For VM case, we ignore component size clauses
2546 -- Give a warning unless we are in GNAT mode, in which case
2547 -- the warning is suppressed since it is not useful.
2549 if not GNAT_Mode then
2551 ("?component size ignored in this configuration", N);
2555 -- Deal with warning on overridden size
2557 if Warn_On_Overridden_Size
2558 and then Has_Size_Clause (Ctyp)
2559 and then RM_Size (Ctyp) /= Csize
2562 ("?component size overrides size clause for&",
2566 Set_Has_Component_Size_Clause (Btype, True);
2567 Set_Has_Non_Standard_Rep (Btype, True);
2569 end Component_Size_Case;
2571 -----------------------
2572 -- Constant_Indexing --
2573 -----------------------
2575 when Attribute_Constant_Indexing =>
2576 Check_Indexing_Functions;
2578 ----------------------
2579 -- Default_Iterator --
2580 ----------------------
2582 when Attribute_Default_Iterator => Default_Iterator : declare
2586 if not Is_Tagged_Type (U_Ent) then
2588 ("aspect Default_Iterator applies to tagged type", Nam);
2591 Check_Iterator_Functions;
2595 if not Is_Entity_Name (Expr)
2596 or else Ekind (Entity (Expr)) /= E_Function
2598 Error_Msg_N ("aspect Iterator must be a function", Expr);
2600 Func := Entity (Expr);
2603 if No (First_Formal (Func))
2604 or else Etype (First_Formal (Func)) /= U_Ent
2607 ("Default Iterator must be a primitive of&", Func, U_Ent);
2609 end Default_Iterator;
2615 when Attribute_External_Tag => External_Tag :
2617 if not Is_Tagged_Type (U_Ent) then
2618 Error_Msg_N ("should be a tagged type", Nam);
2621 if Duplicate_Clause then
2625 Analyze_And_Resolve (Expr, Standard_String);
2627 if not Is_Static_Expression (Expr) then
2628 Flag_Non_Static_Expr
2629 ("static string required for tag name!", Nam);
2632 if VM_Target = No_VM then
2633 Set_Has_External_Tag_Rep_Clause (U_Ent);
2635 Error_Msg_Name_1 := Attr;
2637 ("% attribute unsupported in this configuration", Nam);
2640 if not Is_Library_Level_Entity (U_Ent) then
2642 ("?non-unique external tag supplied for &", N, U_Ent);
2644 ("?\same external tag applies to all subprogram calls", N);
2646 ("?\corresponding internal tag cannot be obtained", N);
2651 --------------------------
2652 -- Implicit_Dereference --
2653 --------------------------
2655 when Attribute_Implicit_Dereference =>
2657 -- Legality checks already performed at the point of
2658 -- the type declaration, aspect is not delayed.
2666 when Attribute_Input =>
2667 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2668 Set_Has_Specified_Stream_Input (Ent);
2670 ----------------------
2671 -- Iterator_Element --
2672 ----------------------
2674 when Attribute_Iterator_Element =>
2677 if not Is_Entity_Name (Expr)
2678 or else not Is_Type (Entity (Expr))
2680 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
2687 -- Machine radix attribute definition clause
2689 when Attribute_Machine_Radix => Machine_Radix : declare
2690 Radix : constant Uint := Static_Integer (Expr);
2693 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2694 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2696 elsif Duplicate_Clause then
2699 elsif Radix /= No_Uint then
2700 Set_Has_Machine_Radix_Clause (U_Ent);
2701 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2705 elsif Radix = 10 then
2706 Set_Machine_Radix_10 (U_Ent);
2708 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2717 -- Object_Size attribute definition clause
2719 when Attribute_Object_Size => Object_Size : declare
2720 Size : constant Uint := Static_Integer (Expr);
2723 pragma Warnings (Off, Biased);
2726 if not Is_Type (U_Ent) then
2727 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2729 elsif Duplicate_Clause then
2733 Check_Size (Expr, U_Ent, Size, Biased);
2741 UI_Mod (Size, 64) /= 0
2744 ("Object_Size must be 8, 16, 32, or multiple of 64",
2748 Set_Esize (U_Ent, Size);
2749 Set_Has_Object_Size_Clause (U_Ent);
2750 Alignment_Check_For_Size_Change (U_Ent, Size);
2758 when Attribute_Output =>
2759 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2760 Set_Has_Specified_Stream_Output (Ent);
2766 when Attribute_Read =>
2767 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2768 Set_Has_Specified_Stream_Read (Ent);
2774 -- Size attribute definition clause
2776 when Attribute_Size => Size : declare
2777 Size : constant Uint := Static_Integer (Expr);
2784 if Duplicate_Clause then
2787 elsif not Is_Type (U_Ent)
2788 and then Ekind (U_Ent) /= E_Variable
2789 and then Ekind (U_Ent) /= E_Constant
2791 Error_Msg_N ("size cannot be given for &", Nam);
2793 elsif Is_Array_Type (U_Ent)
2794 and then not Is_Constrained (U_Ent)
2797 ("size cannot be given for unconstrained array", Nam);
2799 elsif Size /= No_Uint then
2800 if VM_Target /= No_VM and then not GNAT_Mode then
2802 -- Size clause is not handled properly on VM targets.
2803 -- Display a warning unless we are in GNAT mode, in which
2804 -- case this is useless.
2807 ("?size clauses are ignored in this configuration", N);
2810 if Is_Type (U_Ent) then
2813 Etyp := Etype (U_Ent);
2816 -- Check size, note that Gigi is in charge of checking that the
2817 -- size of an array or record type is OK. Also we do not check
2818 -- the size in the ordinary fixed-point case, since it is too
2819 -- early to do so (there may be subsequent small clause that
2820 -- affects the size). We can check the size if a small clause
2821 -- has already been given.
2823 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2824 or else Has_Small_Clause (U_Ent)
2826 Check_Size (Expr, Etyp, Size, Biased);
2827 Set_Biased (U_Ent, N, "size clause", Biased);
2830 -- For types set RM_Size and Esize if possible
2832 if Is_Type (U_Ent) then
2833 Set_RM_Size (U_Ent, Size);
2835 -- For elementary types, increase Object_Size to power of 2,
2836 -- but not less than a storage unit in any case (normally
2837 -- this means it will be byte addressable).
2839 -- For all other types, nothing else to do, we leave Esize
2840 -- (object size) unset, the back end will set it from the
2841 -- size and alignment in an appropriate manner.
2843 -- In both cases, we check whether the alignment must be
2844 -- reset in the wake of the size change.
2846 if Is_Elementary_Type (U_Ent) then
2847 if Size <= System_Storage_Unit then
2848 Init_Esize (U_Ent, System_Storage_Unit);
2849 elsif Size <= 16 then
2850 Init_Esize (U_Ent, 16);
2851 elsif Size <= 32 then
2852 Init_Esize (U_Ent, 32);
2854 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2857 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
2859 Alignment_Check_For_Size_Change (U_Ent, Size);
2862 -- For objects, set Esize only
2865 if Is_Elementary_Type (Etyp) then
2866 if Size /= System_Storage_Unit
2868 Size /= System_Storage_Unit * 2
2870 Size /= System_Storage_Unit * 4
2872 Size /= System_Storage_Unit * 8
2874 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2875 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2877 ("size for primitive object must be a power of 2"
2878 & " in the range ^-^", N);
2882 Set_Esize (U_Ent, Size);
2885 Set_Has_Size_Clause (U_Ent);
2893 -- Small attribute definition clause
2895 when Attribute_Small => Small : declare
2896 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2900 Analyze_And_Resolve (Expr, Any_Real);
2902 if Etype (Expr) = Any_Type then
2905 elsif not Is_Static_Expression (Expr) then
2906 Flag_Non_Static_Expr
2907 ("small requires static expression!", Expr);
2911 Small := Expr_Value_R (Expr);
2913 if Small <= Ureal_0 then
2914 Error_Msg_N ("small value must be greater than zero", Expr);
2920 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2922 ("small requires an ordinary fixed point type", Nam);
2924 elsif Has_Small_Clause (U_Ent) then
2925 Error_Msg_N ("small already given for &", Nam);
2927 elsif Small > Delta_Value (U_Ent) then
2929 ("small value must not be greater then delta value", Nam);
2932 Set_Small_Value (U_Ent, Small);
2933 Set_Small_Value (Implicit_Base, Small);
2934 Set_Has_Small_Clause (U_Ent);
2935 Set_Has_Small_Clause (Implicit_Base);
2936 Set_Has_Non_Standard_Rep (Implicit_Base);
2944 -- Storage_Pool attribute definition clause
2946 when Attribute_Storage_Pool => Storage_Pool : declare
2951 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2953 ("storage pool cannot be given for access-to-subprogram type",
2958 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2961 ("storage pool can only be given for access types", Nam);
2964 elsif Is_Derived_Type (U_Ent) then
2966 ("storage pool cannot be given for a derived access type",
2969 elsif Duplicate_Clause then
2972 elsif Present (Associated_Storage_Pool (U_Ent)) then
2973 Error_Msg_N ("storage pool already given for &", Nam);
2978 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
2980 if not Denotes_Variable (Expr) then
2981 Error_Msg_N ("storage pool must be a variable", Expr);
2985 if Nkind (Expr) = N_Type_Conversion then
2986 T := Etype (Expression (Expr));
2991 -- The Stack_Bounded_Pool is used internally for implementing
2992 -- access types with a Storage_Size. Since it only work properly
2993 -- when used on one specific type, we need to check that it is not
2994 -- hijacked improperly:
2996 -- type T is access Integer;
2997 -- for T'Storage_Size use n;
2998 -- type Q is access Float;
2999 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
3001 if RTE_Available (RE_Stack_Bounded_Pool)
3002 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
3004 Error_Msg_N ("non-shareable internal Pool", Expr);
3008 -- If the argument is a name that is not an entity name, then
3009 -- we construct a renaming operation to define an entity of
3010 -- type storage pool.
3012 if not Is_Entity_Name (Expr)
3013 and then Is_Object_Reference (Expr)
3015 Pool := Make_Temporary (Loc, 'P', Expr);
3018 Rnode : constant Node_Id :=
3019 Make_Object_Renaming_Declaration (Loc,
3020 Defining_Identifier => Pool,
3022 New_Occurrence_Of (Etype (Expr), Loc),
3026 Insert_Before (N, Rnode);
3028 Set_Associated_Storage_Pool (U_Ent, Pool);
3031 elsif Is_Entity_Name (Expr) then
3032 Pool := Entity (Expr);
3034 -- If pool is a renamed object, get original one. This can
3035 -- happen with an explicit renaming, and within instances.
3037 while Present (Renamed_Object (Pool))
3038 and then Is_Entity_Name (Renamed_Object (Pool))
3040 Pool := Entity (Renamed_Object (Pool));
3043 if Present (Renamed_Object (Pool))
3044 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
3045 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
3047 Pool := Entity (Expression (Renamed_Object (Pool)));
3050 Set_Associated_Storage_Pool (U_Ent, Pool);
3052 elsif Nkind (Expr) = N_Type_Conversion
3053 and then Is_Entity_Name (Expression (Expr))
3054 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
3056 Pool := Entity (Expression (Expr));
3057 Set_Associated_Storage_Pool (U_Ent, Pool);
3060 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
3069 -- Storage_Size attribute definition clause
3071 when Attribute_Storage_Size => Storage_Size : declare
3072 Btype : constant Entity_Id := Base_Type (U_Ent);
3076 if Is_Task_Type (U_Ent) then
3077 Check_Restriction (No_Obsolescent_Features, N);
3079 if Warn_On_Obsolescent_Feature then
3081 ("storage size clause for task is an " &
3082 "obsolescent feature (RM J.9)?", N);
3083 Error_Msg_N ("\use Storage_Size pragma instead?", N);
3089 if not Is_Access_Type (U_Ent)
3090 and then Ekind (U_Ent) /= E_Task_Type
3092 Error_Msg_N ("storage size cannot be given for &", Nam);
3094 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
3096 ("storage size cannot be given for a derived access type",
3099 elsif Duplicate_Clause then
3103 Analyze_And_Resolve (Expr, Any_Integer);
3105 if Is_Access_Type (U_Ent) then
3106 if Present (Associated_Storage_Pool (U_Ent)) then
3107 Error_Msg_N ("storage pool already given for &", Nam);
3111 if Is_OK_Static_Expression (Expr)
3112 and then Expr_Value (Expr) = 0
3114 Set_No_Pool_Assigned (Btype);
3117 else -- Is_Task_Type (U_Ent)
3118 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
3120 if Present (Sprag) then
3121 Error_Msg_Sloc := Sloc (Sprag);
3123 ("Storage_Size already specified#", Nam);
3128 Set_Has_Storage_Size_Clause (Btype);
3136 when Attribute_Stream_Size => Stream_Size : declare
3137 Size : constant Uint := Static_Integer (Expr);
3140 if Ada_Version <= Ada_95 then
3141 Check_Restriction (No_Implementation_Attributes, N);
3144 if Duplicate_Clause then
3147 elsif Is_Elementary_Type (U_Ent) then
3148 if Size /= System_Storage_Unit
3150 Size /= System_Storage_Unit * 2
3152 Size /= System_Storage_Unit * 4
3154 Size /= System_Storage_Unit * 8
3156 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
3158 ("stream size for elementary type must be a"
3159 & " power of 2 and at least ^", N);
3161 elsif RM_Size (U_Ent) > Size then
3162 Error_Msg_Uint_1 := RM_Size (U_Ent);
3164 ("stream size for elementary type must be a"
3165 & " power of 2 and at least ^", N);
3168 Set_Has_Stream_Size_Clause (U_Ent);
3171 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
3179 -- Value_Size attribute definition clause
3181 when Attribute_Value_Size => Value_Size : declare
3182 Size : constant Uint := Static_Integer (Expr);
3186 if not Is_Type (U_Ent) then
3187 Error_Msg_N ("Value_Size cannot be given for &", Nam);
3189 elsif Duplicate_Clause then
3192 elsif Is_Array_Type (U_Ent)
3193 and then not Is_Constrained (U_Ent)
3196 ("Value_Size cannot be given for unconstrained array", Nam);
3199 if Is_Elementary_Type (U_Ent) then
3200 Check_Size (Expr, U_Ent, Size, Biased);
3201 Set_Biased (U_Ent, N, "value size clause", Biased);
3204 Set_RM_Size (U_Ent, Size);
3208 -----------------------
3209 -- Variable_Indexing --
3210 -----------------------
3212 when Attribute_Variable_Indexing =>
3213 Check_Indexing_Functions;
3219 when Attribute_Write =>
3220 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
3221 Set_Has_Specified_Stream_Write (Ent);
3223 -- All other attributes cannot be set
3227 ("attribute& cannot be set with definition clause", N);
3230 -- The test for the type being frozen must be performed after any
3231 -- expression the clause has been analyzed since the expression itself
3232 -- might cause freezing that makes the clause illegal.
3234 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
3237 end Analyze_Attribute_Definition_Clause;
3239 ----------------------------
3240 -- Analyze_Code_Statement --
3241 ----------------------------
3243 procedure Analyze_Code_Statement (N : Node_Id) is
3244 HSS : constant Node_Id := Parent (N);
3245 SBody : constant Node_Id := Parent (HSS);
3246 Subp : constant Entity_Id := Current_Scope;
3253 -- Analyze and check we get right type, note that this implements the
3254 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
3255 -- is the only way that Asm_Insn could possibly be visible.
3257 Analyze_And_Resolve (Expression (N));
3259 if Etype (Expression (N)) = Any_Type then
3261 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
3262 Error_Msg_N ("incorrect type for code statement", N);
3266 Check_Code_Statement (N);
3268 -- Make sure we appear in the handled statement sequence of a
3269 -- subprogram (RM 13.8(3)).
3271 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
3272 or else Nkind (SBody) /= N_Subprogram_Body
3275 ("code statement can only appear in body of subprogram", N);
3279 -- Do remaining checks (RM 13.8(3)) if not already done
3281 if not Is_Machine_Code_Subprogram (Subp) then
3282 Set_Is_Machine_Code_Subprogram (Subp);
3284 -- No exception handlers allowed
3286 if Present (Exception_Handlers (HSS)) then
3288 ("exception handlers not permitted in machine code subprogram",
3289 First (Exception_Handlers (HSS)));
3292 -- No declarations other than use clauses and pragmas (we allow
3293 -- certain internally generated declarations as well).
3295 Decl := First (Declarations (SBody));
3296 while Present (Decl) loop
3297 DeclO := Original_Node (Decl);
3298 if Comes_From_Source (DeclO)
3299 and not Nkind_In (DeclO, N_Pragma,
3300 N_Use_Package_Clause,
3302 N_Implicit_Label_Declaration)
3305 ("this declaration not allowed in machine code subprogram",
3312 -- No statements other than code statements, pragmas, and labels.
3313 -- Again we allow certain internally generated statements.
3315 Stmt := First (Statements (HSS));
3316 while Present (Stmt) loop
3317 StmtO := Original_Node (Stmt);
3318 if Comes_From_Source (StmtO)
3319 and then not Nkind_In (StmtO, N_Pragma,
3324 ("this statement is not allowed in machine code subprogram",
3331 end Analyze_Code_Statement;
3333 -----------------------------------------------
3334 -- Analyze_Enumeration_Representation_Clause --
3335 -----------------------------------------------
3337 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
3338 Ident : constant Node_Id := Identifier (N);
3339 Aggr : constant Node_Id := Array_Aggregate (N);
3340 Enumtype : Entity_Id;
3347 Err : Boolean := False;
3348 -- Set True to avoid cascade errors and crashes on incorrect source code
3350 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
3351 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
3352 -- Allowed range of universal integer (= allowed range of enum lit vals)
3356 -- Minimum and maximum values of entries
3359 -- Pointer to node for literal providing max value
3362 if Ignore_Rep_Clauses then
3366 -- First some basic error checks
3369 Enumtype := Entity (Ident);
3371 if Enumtype = Any_Type
3372 or else Rep_Item_Too_Early (Enumtype, N)
3376 Enumtype := Underlying_Type (Enumtype);
3379 if not Is_Enumeration_Type (Enumtype) then
3381 ("enumeration type required, found}",
3382 Ident, First_Subtype (Enumtype));
3386 -- Ignore rep clause on generic actual type. This will already have
3387 -- been flagged on the template as an error, and this is the safest
3388 -- way to ensure we don't get a junk cascaded message in the instance.
3390 if Is_Generic_Actual_Type (Enumtype) then
3393 -- Type must be in current scope
3395 elsif Scope (Enumtype) /= Current_Scope then
3396 Error_Msg_N ("type must be declared in this scope", Ident);
3399 -- Type must be a first subtype
3401 elsif not Is_First_Subtype (Enumtype) then
3402 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
3405 -- Ignore duplicate rep clause
3407 elsif Has_Enumeration_Rep_Clause (Enumtype) then
3408 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
3411 -- Don't allow rep clause for standard [wide_[wide_]]character
3413 elsif Is_Standard_Character_Type (Enumtype) then
3414 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
3417 -- Check that the expression is a proper aggregate (no parentheses)
3419 elsif Paren_Count (Aggr) /= 0 then
3421 ("extra parentheses surrounding aggregate not allowed",
3425 -- All tests passed, so set rep clause in place
3428 Set_Has_Enumeration_Rep_Clause (Enumtype);
3429 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
3432 -- Now we process the aggregate. Note that we don't use the normal
3433 -- aggregate code for this purpose, because we don't want any of the
3434 -- normal expansion activities, and a number of special semantic
3435 -- rules apply (including the component type being any integer type)
3437 Elit := First_Literal (Enumtype);
3439 -- First the positional entries if any
3441 if Present (Expressions (Aggr)) then
3442 Expr := First (Expressions (Aggr));
3443 while Present (Expr) loop
3445 Error_Msg_N ("too many entries in aggregate", Expr);
3449 Val := Static_Integer (Expr);
3451 -- Err signals that we found some incorrect entries processing
3452 -- the list. The final checks for completeness and ordering are
3453 -- skipped in this case.
3455 if Val = No_Uint then
3457 elsif Val < Lo or else Hi < Val then
3458 Error_Msg_N ("value outside permitted range", Expr);
3462 Set_Enumeration_Rep (Elit, Val);
3463 Set_Enumeration_Rep_Expr (Elit, Expr);
3469 -- Now process the named entries if present
3471 if Present (Component_Associations (Aggr)) then
3472 Assoc := First (Component_Associations (Aggr));
3473 while Present (Assoc) loop
3474 Choice := First (Choices (Assoc));
3476 if Present (Next (Choice)) then
3478 ("multiple choice not allowed here", Next (Choice));
3482 if Nkind (Choice) = N_Others_Choice then
3483 Error_Msg_N ("others choice not allowed here", Choice);
3486 elsif Nkind (Choice) = N_Range then
3488 -- ??? should allow zero/one element range here
3490 Error_Msg_N ("range not allowed here", Choice);
3494 Analyze_And_Resolve (Choice, Enumtype);
3496 if Error_Posted (Choice) then
3501 if Is_Entity_Name (Choice)
3502 and then Is_Type (Entity (Choice))
3504 Error_Msg_N ("subtype name not allowed here", Choice);
3507 -- ??? should allow static subtype with zero/one entry
3509 elsif Etype (Choice) = Base_Type (Enumtype) then
3510 if not Is_Static_Expression (Choice) then
3511 Flag_Non_Static_Expr
3512 ("non-static expression used for choice!", Choice);
3516 Elit := Expr_Value_E (Choice);
3518 if Present (Enumeration_Rep_Expr (Elit)) then
3520 Sloc (Enumeration_Rep_Expr (Elit));
3522 ("representation for& previously given#",
3527 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
3529 Expr := Expression (Assoc);
3530 Val := Static_Integer (Expr);
3532 if Val = No_Uint then
3535 elsif Val < Lo or else Hi < Val then
3536 Error_Msg_N ("value outside permitted range", Expr);
3540 Set_Enumeration_Rep (Elit, Val);
3550 -- Aggregate is fully processed. Now we check that a full set of
3551 -- representations was given, and that they are in range and in order.
3552 -- These checks are only done if no other errors occurred.
3558 Elit := First_Literal (Enumtype);
3559 while Present (Elit) loop
3560 if No (Enumeration_Rep_Expr (Elit)) then
3561 Error_Msg_NE ("missing representation for&!", N, Elit);
3564 Val := Enumeration_Rep (Elit);
3566 if Min = No_Uint then
3570 if Val /= No_Uint then
3571 if Max /= No_Uint and then Val <= Max then
3573 ("enumeration value for& not ordered!",
3574 Enumeration_Rep_Expr (Elit), Elit);
3577 Max_Node := Enumeration_Rep_Expr (Elit);
3581 -- If there is at least one literal whose representation is not
3582 -- equal to the Pos value, then note that this enumeration type
3583 -- has a non-standard representation.
3585 if Val /= Enumeration_Pos (Elit) then
3586 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3593 -- Now set proper size information
3596 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3599 if Has_Size_Clause (Enumtype) then
3601 -- All OK, if size is OK now
3603 if RM_Size (Enumtype) >= Minsize then
3607 -- Try if we can get by with biasing
3610 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3612 -- Error message if even biasing does not work
3614 if RM_Size (Enumtype) < Minsize then
3615 Error_Msg_Uint_1 := RM_Size (Enumtype);
3616 Error_Msg_Uint_2 := Max;
3618 ("previously given size (^) is too small "
3619 & "for this value (^)", Max_Node);
3621 -- If biasing worked, indicate that we now have biased rep
3625 (Enumtype, Size_Clause (Enumtype), "size clause");
3630 Set_RM_Size (Enumtype, Minsize);
3631 Set_Enum_Esize (Enumtype);
3634 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3635 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3636 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3640 -- We repeat the too late test in case it froze itself!
3642 if Rep_Item_Too_Late (Enumtype, N) then
3645 end Analyze_Enumeration_Representation_Clause;
3647 ----------------------------
3648 -- Analyze_Free_Statement --
3649 ----------------------------
3651 procedure Analyze_Free_Statement (N : Node_Id) is
3653 Analyze (Expression (N));
3654 end Analyze_Free_Statement;
3656 ---------------------------
3657 -- Analyze_Freeze_Entity --
3658 ---------------------------
3660 procedure Analyze_Freeze_Entity (N : Node_Id) is
3661 E : constant Entity_Id := Entity (N);
3664 -- Remember that we are processing a freezing entity. Required to
3665 -- ensure correct decoration of internal entities associated with
3666 -- interfaces (see New_Overloaded_Entity).
3668 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3670 -- For tagged types covering interfaces add internal entities that link
3671 -- the primitives of the interfaces with the primitives that cover them.
3672 -- Note: These entities were originally generated only when generating
3673 -- code because their main purpose was to provide support to initialize
3674 -- the secondary dispatch tables. They are now generated also when
3675 -- compiling with no code generation to provide ASIS the relationship
3676 -- between interface primitives and tagged type primitives. They are
3677 -- also used to locate primitives covering interfaces when processing
3678 -- generics (see Derive_Subprograms).
3680 if Ada_Version >= Ada_2005
3681 and then Ekind (E) = E_Record_Type
3682 and then Is_Tagged_Type (E)
3683 and then not Is_Interface (E)
3684 and then Has_Interfaces (E)
3686 -- This would be a good common place to call the routine that checks
3687 -- overriding of interface primitives (and thus factorize calls to
3688 -- Check_Abstract_Overriding located at different contexts in the
3689 -- compiler). However, this is not possible because it causes
3690 -- spurious errors in case of late overriding.
3692 Add_Internal_Interface_Entities (E);
3697 if Ekind (E) = E_Record_Type
3698 and then Is_CPP_Class (E)
3699 and then Is_Tagged_Type (E)
3700 and then Tagged_Type_Expansion
3701 and then Expander_Active
3703 if CPP_Num_Prims (E) = 0 then
3705 -- If the CPP type has user defined components then it must import
3706 -- primitives from C++. This is required because if the C++ class
3707 -- has no primitives then the C++ compiler does not added the _tag
3708 -- component to the type.
3710 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3712 if First_Entity (E) /= Last_Entity (E) then
3714 ("?'C'P'P type must import at least one primitive from C++",
3719 -- Check that all its primitives are abstract or imported from C++.
3720 -- Check also availability of the C++ constructor.
3723 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3725 Error_Reported : Boolean := False;
3729 Elmt := First_Elmt (Primitive_Operations (E));
3730 while Present (Elmt) loop
3731 Prim := Node (Elmt);
3733 if Comes_From_Source (Prim) then
3734 if Is_Abstract_Subprogram (Prim) then
3737 elsif not Is_Imported (Prim)
3738 or else Convention (Prim) /= Convention_CPP
3741 ("?primitives of 'C'P'P types must be imported from C++"
3742 & " or abstract", Prim);
3744 elsif not Has_Constructors
3745 and then not Error_Reported
3747 Error_Msg_Name_1 := Chars (E);
3749 ("?'C'P'P constructor required for type %", Prim);
3750 Error_Reported := True;
3759 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3761 -- If we have a type with predicates, build predicate function
3763 if Is_Type (E) and then Has_Predicates (E) then
3764 Build_Predicate_Function (E, N);
3767 -- If type has delayed aspects, this is where we do the preanalysis at
3768 -- the freeze point, as part of the consistent visibility check. Note
3769 -- that this must be done after calling Build_Predicate_Function or
3770 -- Build_Invariant_Procedure since these subprograms fix occurrences of
3771 -- the subtype name in the saved expression so that they will not cause
3772 -- trouble in the preanalysis.
3774 if Has_Delayed_Aspects (E) then
3779 -- Look for aspect specification entries for this entity
3781 Ritem := First_Rep_Item (E);
3782 while Present (Ritem) loop
3783 if Nkind (Ritem) = N_Aspect_Specification
3784 and then Entity (Ritem) = E
3785 and then Is_Delayed_Aspect (Ritem)
3786 and then Scope (E) = Current_Scope
3788 Check_Aspect_At_Freeze_Point (Ritem);
3791 Next_Rep_Item (Ritem);
3795 end Analyze_Freeze_Entity;
3797 ------------------------------------------
3798 -- Analyze_Record_Representation_Clause --
3799 ------------------------------------------
3801 -- Note: we check as much as we can here, but we can't do any checks
3802 -- based on the position values (e.g. overlap checks) until freeze time
3803 -- because especially in Ada 2005 (machine scalar mode), the processing
3804 -- for non-standard bit order can substantially change the positions.
3805 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3806 -- for the remainder of this processing.
3808 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3809 Ident : constant Node_Id := Identifier (N);
3814 Hbit : Uint := Uint_0;
3818 Rectype : Entity_Id;
3820 CR_Pragma : Node_Id := Empty;
3821 -- Points to N_Pragma node if Complete_Representation pragma present
3824 if Ignore_Rep_Clauses then
3829 Rectype := Entity (Ident);
3831 if Rectype = Any_Type
3832 or else Rep_Item_Too_Early (Rectype, N)
3836 Rectype := Underlying_Type (Rectype);
3839 -- First some basic error checks
3841 if not Is_Record_Type (Rectype) then
3843 ("record type required, found}", Ident, First_Subtype (Rectype));
3846 elsif Scope (Rectype) /= Current_Scope then
3847 Error_Msg_N ("type must be declared in this scope", N);
3850 elsif not Is_First_Subtype (Rectype) then
3851 Error_Msg_N ("cannot give record rep clause for subtype", N);
3854 elsif Has_Record_Rep_Clause (Rectype) then
3855 Error_Msg_N ("duplicate record rep clause ignored", N);
3858 elsif Rep_Item_Too_Late (Rectype, N) then
3862 if Present (Mod_Clause (N)) then
3864 Loc : constant Source_Ptr := Sloc (N);
3865 M : constant Node_Id := Mod_Clause (N);
3866 P : constant List_Id := Pragmas_Before (M);
3870 pragma Warnings (Off, Mod_Val);
3873 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3875 if Warn_On_Obsolescent_Feature then
3877 ("mod clause is an obsolescent feature (RM J.8)?", N);
3879 ("\use alignment attribute definition clause instead?", N);
3886 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3887 -- the Mod clause into an alignment clause anyway, so that the
3888 -- back-end can compute and back-annotate properly the size and
3889 -- alignment of types that may include this record.
3891 -- This seems dubious, this destroys the source tree in a manner
3892 -- not detectable by ASIS ???
3894 if Operating_Mode = Check_Semantics
3898 Make_Attribute_Definition_Clause (Loc,
3899 Name => New_Reference_To (Base_Type (Rectype), Loc),
3900 Chars => Name_Alignment,
3901 Expression => Relocate_Node (Expression (M)));
3903 Set_From_At_Mod (AtM_Nod);
3904 Insert_After (N, AtM_Nod);
3905 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3906 Set_Mod_Clause (N, Empty);
3909 -- Get the alignment value to perform error checking
3911 Mod_Val := Get_Alignment_Value (Expression (M));
3916 -- For untagged types, clear any existing component clauses for the
3917 -- type. If the type is derived, this is what allows us to override
3918 -- a rep clause for the parent. For type extensions, the representation
3919 -- of the inherited components is inherited, so we want to keep previous
3920 -- component clauses for completeness.
3922 if not Is_Tagged_Type (Rectype) then
3923 Comp := First_Component_Or_Discriminant (Rectype);
3924 while Present (Comp) loop
3925 Set_Component_Clause (Comp, Empty);
3926 Next_Component_Or_Discriminant (Comp);
3930 -- All done if no component clauses
3932 CC := First (Component_Clauses (N));
3938 -- A representation like this applies to the base type
3940 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3941 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3942 Set_Has_Specified_Layout (Base_Type (Rectype));
3944 -- Process the component clauses
3946 while Present (CC) loop
3950 if Nkind (CC) = N_Pragma then
3953 -- The only pragma of interest is Complete_Representation
3955 if Pragma_Name (CC) = Name_Complete_Representation then
3959 -- Processing for real component clause
3962 Posit := Static_Integer (Position (CC));
3963 Fbit := Static_Integer (First_Bit (CC));
3964 Lbit := Static_Integer (Last_Bit (CC));
3967 and then Fbit /= No_Uint
3968 and then Lbit /= No_Uint
3972 ("position cannot be negative", Position (CC));
3976 ("first bit cannot be negative", First_Bit (CC));
3978 -- The Last_Bit specified in a component clause must not be
3979 -- less than the First_Bit minus one (RM-13.5.1(10)).
3981 elsif Lbit < Fbit - 1 then
3983 ("last bit cannot be less than first bit minus one",
3986 -- Values look OK, so find the corresponding record component
3987 -- Even though the syntax allows an attribute reference for
3988 -- implementation-defined components, GNAT does not allow the
3989 -- tag to get an explicit position.
3991 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
3992 if Attribute_Name (Component_Name (CC)) = Name_Tag then
3993 Error_Msg_N ("position of tag cannot be specified", CC);
3995 Error_Msg_N ("illegal component name", CC);
3999 Comp := First_Entity (Rectype);
4000 while Present (Comp) loop
4001 exit when Chars (Comp) = Chars (Component_Name (CC));
4007 -- Maybe component of base type that is absent from
4008 -- statically constrained first subtype.
4010 Comp := First_Entity (Base_Type (Rectype));
4011 while Present (Comp) loop
4012 exit when Chars (Comp) = Chars (Component_Name (CC));
4019 ("component clause is for non-existent field", CC);
4021 -- Ada 2012 (AI05-0026): Any name that denotes a
4022 -- discriminant of an object of an unchecked union type
4023 -- shall not occur within a record_representation_clause.
4025 -- The general restriction of using record rep clauses on
4026 -- Unchecked_Union types has now been lifted. Since it is
4027 -- possible to introduce a record rep clause which mentions
4028 -- the discriminant of an Unchecked_Union in non-Ada 2012
4029 -- code, this check is applied to all versions of the
4032 elsif Ekind (Comp) = E_Discriminant
4033 and then Is_Unchecked_Union (Rectype)
4036 ("cannot reference discriminant of Unchecked_Union",
4037 Component_Name (CC));
4039 elsif Present (Component_Clause (Comp)) then
4041 -- Diagnose duplicate rep clause, or check consistency
4042 -- if this is an inherited component. In a double fault,
4043 -- there may be a duplicate inconsistent clause for an
4044 -- inherited component.
4046 if Scope (Original_Record_Component (Comp)) = Rectype
4047 or else Parent (Component_Clause (Comp)) = N
4049 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
4050 Error_Msg_N ("component clause previously given#", CC);
4054 Rep1 : constant Node_Id := Component_Clause (Comp);
4056 if Intval (Position (Rep1)) /=
4057 Intval (Position (CC))
4058 or else Intval (First_Bit (Rep1)) /=
4059 Intval (First_Bit (CC))
4060 or else Intval (Last_Bit (Rep1)) /=
4061 Intval (Last_Bit (CC))
4063 Error_Msg_N ("component clause inconsistent "
4064 & "with representation of ancestor", CC);
4065 elsif Warn_On_Redundant_Constructs then
4066 Error_Msg_N ("?redundant component clause "
4067 & "for inherited component!", CC);
4072 -- Normal case where this is the first component clause we
4073 -- have seen for this entity, so set it up properly.
4076 -- Make reference for field in record rep clause and set
4077 -- appropriate entity field in the field identifier.
4080 (Comp, Component_Name (CC), Set_Ref => False);
4081 Set_Entity (Component_Name (CC), Comp);
4083 -- Update Fbit and Lbit to the actual bit number
4085 Fbit := Fbit + UI_From_Int (SSU) * Posit;
4086 Lbit := Lbit + UI_From_Int (SSU) * Posit;
4088 if Has_Size_Clause (Rectype)
4089 and then RM_Size (Rectype) <= Lbit
4092 ("bit number out of range of specified size",
4095 Set_Component_Clause (Comp, CC);
4096 Set_Component_Bit_Offset (Comp, Fbit);
4097 Set_Esize (Comp, 1 + (Lbit - Fbit));
4098 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
4099 Set_Normalized_Position (Comp, Fbit / SSU);
4101 if Warn_On_Overridden_Size
4102 and then Has_Size_Clause (Etype (Comp))
4103 and then RM_Size (Etype (Comp)) /= Esize (Comp)
4106 ("?component size overrides size clause for&",
4107 Component_Name (CC), Etype (Comp));
4110 -- This information is also set in the corresponding
4111 -- component of the base type, found by accessing the
4112 -- Original_Record_Component link if it is present.
4114 Ocomp := Original_Record_Component (Comp);
4121 (Component_Name (CC),
4127 (Comp, First_Node (CC), "component clause", Biased);
4129 if Present (Ocomp) then
4130 Set_Component_Clause (Ocomp, CC);
4131 Set_Component_Bit_Offset (Ocomp, Fbit);
4132 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
4133 Set_Normalized_Position (Ocomp, Fbit / SSU);
4134 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
4136 Set_Normalized_Position_Max
4137 (Ocomp, Normalized_Position (Ocomp));
4139 -- Note: we don't use Set_Biased here, because we
4140 -- already gave a warning above if needed, and we
4141 -- would get a duplicate for the same name here.
4143 Set_Has_Biased_Representation
4144 (Ocomp, Has_Biased_Representation (Comp));
4147 if Esize (Comp) < 0 then
4148 Error_Msg_N ("component size is negative", CC);
4159 -- Check missing components if Complete_Representation pragma appeared
4161 if Present (CR_Pragma) then
4162 Comp := First_Component_Or_Discriminant (Rectype);
4163 while Present (Comp) loop
4164 if No (Component_Clause (Comp)) then
4166 ("missing component clause for &", CR_Pragma, Comp);
4169 Next_Component_Or_Discriminant (Comp);
4172 -- If no Complete_Representation pragma, warn if missing components
4174 elsif Warn_On_Unrepped_Components then
4176 Num_Repped_Components : Nat := 0;
4177 Num_Unrepped_Components : Nat := 0;
4180 -- First count number of repped and unrepped components
4182 Comp := First_Component_Or_Discriminant (Rectype);
4183 while Present (Comp) loop
4184 if Present (Component_Clause (Comp)) then
4185 Num_Repped_Components := Num_Repped_Components + 1;
4187 Num_Unrepped_Components := Num_Unrepped_Components + 1;
4190 Next_Component_Or_Discriminant (Comp);
4193 -- We are only interested in the case where there is at least one
4194 -- unrepped component, and at least half the components have rep
4195 -- clauses. We figure that if less than half have them, then the
4196 -- partial rep clause is really intentional. If the component
4197 -- type has no underlying type set at this point (as for a generic
4198 -- formal type), we don't know enough to give a warning on the
4201 if Num_Unrepped_Components > 0
4202 and then Num_Unrepped_Components < Num_Repped_Components
4204 Comp := First_Component_Or_Discriminant (Rectype);
4205 while Present (Comp) loop
4206 if No (Component_Clause (Comp))
4207 and then Comes_From_Source (Comp)
4208 and then Present (Underlying_Type (Etype (Comp)))
4209 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
4210 or else Size_Known_At_Compile_Time
4211 (Underlying_Type (Etype (Comp))))
4212 and then not Has_Warnings_Off (Rectype)
4214 Error_Msg_Sloc := Sloc (Comp);
4216 ("?no component clause given for & declared #",
4220 Next_Component_Or_Discriminant (Comp);
4225 end Analyze_Record_Representation_Clause;
4227 -------------------------------
4228 -- Build_Invariant_Procedure --
4229 -------------------------------
4231 -- The procedure that is constructed here has the form
4233 -- procedure typInvariant (Ixxx : typ) is
4235 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4236 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4238 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
4240 -- end typInvariant;
4242 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
4243 Loc : constant Source_Ptr := Sloc (Typ);
4250 Visible_Decls : constant List_Id := Visible_Declarations (N);
4251 Private_Decls : constant List_Id := Private_Declarations (N);
4253 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
4254 -- Appends statements to Stmts for any invariants in the rep item chain
4255 -- of the given type. If Inherit is False, then we only process entries
4256 -- on the chain for the type Typ. If Inherit is True, then we ignore any
4257 -- Invariant aspects, but we process all Invariant'Class aspects, adding
4258 -- "inherited" to the exception message and generating an informational
4259 -- message about the inheritance of an invariant.
4261 Object_Name : constant Name_Id := New_Internal_Name ('I');
4262 -- Name for argument of invariant procedure
4264 Object_Entity : constant Node_Id :=
4265 Make_Defining_Identifier (Loc, Object_Name);
4266 -- The procedure declaration entity for the argument
4268 --------------------
4269 -- Add_Invariants --
4270 --------------------
4272 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
4282 procedure Replace_Type_Reference (N : Node_Id);
4283 -- Replace a single occurrence N of the subtype name with a reference
4284 -- to the formal of the predicate function. N can be an identifier
4285 -- referencing the subtype, or a selected component, representing an
4286 -- appropriately qualified occurrence of the subtype name.
4288 procedure Replace_Type_References is
4289 new Replace_Type_References_Generic (Replace_Type_Reference);
4290 -- Traverse an expression replacing all occurrences of the subtype
4291 -- name with appropriate references to the object that is the formal
4292 -- parameter of the predicate function. Note that we must ensure
4293 -- that the type and entity information is properly set in the
4294 -- replacement node, since we will do a Preanalyze call of this
4295 -- expression without proper visibility of the procedure argument.
4297 ----------------------------
4298 -- Replace_Type_Reference --
4299 ----------------------------
4301 procedure Replace_Type_Reference (N : Node_Id) is
4303 -- Invariant'Class, replace with T'Class (obj)
4305 if Class_Present (Ritem) then
4307 Make_Type_Conversion (Loc,
4309 Make_Attribute_Reference (Loc,
4310 Prefix => New_Occurrence_Of (T, Loc),
4311 Attribute_Name => Name_Class),
4312 Expression => Make_Identifier (Loc, Object_Name)));
4314 Set_Entity (Expression (N), Object_Entity);
4315 Set_Etype (Expression (N), Typ);
4317 -- Invariant, replace with obj
4320 Rewrite (N, Make_Identifier (Loc, Object_Name));
4321 Set_Entity (N, Object_Entity);
4324 end Replace_Type_Reference;
4326 -- Start of processing for Add_Invariants
4329 Ritem := First_Rep_Item (T);
4330 while Present (Ritem) loop
4331 if Nkind (Ritem) = N_Pragma
4332 and then Pragma_Name (Ritem) = Name_Invariant
4334 Arg1 := First (Pragma_Argument_Associations (Ritem));
4335 Arg2 := Next (Arg1);
4336 Arg3 := Next (Arg2);
4338 Arg1 := Get_Pragma_Arg (Arg1);
4339 Arg2 := Get_Pragma_Arg (Arg2);
4341 -- For Inherit case, ignore Invariant, process only Class case
4344 if not Class_Present (Ritem) then
4348 -- For Inherit false, process only item for right type
4351 if Entity (Arg1) /= Typ then
4357 Stmts := Empty_List;
4360 Exp := New_Copy_Tree (Arg2);
4363 -- We need to replace any occurrences of the name of the type
4364 -- with references to the object, converted to type'Class in
4365 -- the case of Invariant'Class aspects.
4367 Replace_Type_References (Exp, Chars (T));
4369 -- If this invariant comes from an aspect, find the aspect
4370 -- specification, and replace the saved expression because
4371 -- we need the subtype references replaced for the calls to
4372 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4373 -- and Check_Aspect_At_End_Of_Declarations.
4375 if From_Aspect_Specification (Ritem) then
4380 -- Loop to find corresponding aspect, note that this
4381 -- must be present given the pragma is marked delayed.
4383 Aitem := Next_Rep_Item (Ritem);
4384 while Present (Aitem) loop
4385 if Nkind (Aitem) = N_Aspect_Specification
4386 and then Aspect_Rep_Item (Aitem) = Ritem
4389 (Identifier (Aitem), New_Copy_Tree (Exp));
4393 Aitem := Next_Rep_Item (Aitem);
4398 -- Now we need to preanalyze the expression to properly capture
4399 -- the visibility in the visible part. The expression will not
4400 -- be analyzed for real until the body is analyzed, but that is
4401 -- at the end of the private part and has the wrong visibility.
4403 Set_Parent (Exp, N);
4404 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
4406 -- Build first two arguments for Check pragma
4409 Make_Pragma_Argument_Association (Loc,
4410 Expression => Make_Identifier (Loc, Name_Invariant)),
4411 Make_Pragma_Argument_Association (Loc, Expression => Exp));
4413 -- Add message if present in Invariant pragma
4415 if Present (Arg3) then
4416 Str := Strval (Get_Pragma_Arg (Arg3));
4418 -- If inherited case, and message starts "failed invariant",
4419 -- change it to be "failed inherited invariant".
4422 String_To_Name_Buffer (Str);
4424 if Name_Buffer (1 .. 16) = "failed invariant" then
4425 Insert_Str_In_Name_Buffer ("inherited ", 8);
4426 Str := String_From_Name_Buffer;
4431 Make_Pragma_Argument_Association (Loc,
4432 Expression => Make_String_Literal (Loc, Str)));
4435 -- Add Check pragma to list of statements
4439 Pragma_Identifier =>
4440 Make_Identifier (Loc, Name_Check),
4441 Pragma_Argument_Associations => Assoc));
4443 -- If Inherited case and option enabled, output info msg. Note
4444 -- that we know this is a case of Invariant'Class.
4446 if Inherit and Opt.List_Inherited_Aspects then
4447 Error_Msg_Sloc := Sloc (Ritem);
4449 ("?info: & inherits `Invariant''Class` aspect from #",
4455 Next_Rep_Item (Ritem);
4459 -- Start of processing for Build_Invariant_Procedure
4465 Set_Etype (Object_Entity, Typ);
4467 -- Add invariants for the current type
4469 Add_Invariants (Typ, Inherit => False);
4471 -- Add invariants for parent types
4474 Current_Typ : Entity_Id;
4475 Parent_Typ : Entity_Id;
4480 Parent_Typ := Etype (Current_Typ);
4482 if Is_Private_Type (Parent_Typ)
4483 and then Present (Full_View (Base_Type (Parent_Typ)))
4485 Parent_Typ := Full_View (Base_Type (Parent_Typ));
4488 exit when Parent_Typ = Current_Typ;
4490 Current_Typ := Parent_Typ;
4491 Add_Invariants (Current_Typ, Inherit => True);
4495 -- Build the procedure if we generated at least one Check pragma
4497 if Stmts /= No_List then
4499 -- Build procedure declaration
4502 Make_Defining_Identifier (Loc,
4503 Chars => New_External_Name (Chars (Typ), "Invariant"));
4504 Set_Has_Invariants (SId);
4505 Set_Invariant_Procedure (Typ, SId);
4508 Make_Procedure_Specification (Loc,
4509 Defining_Unit_Name => SId,
4510 Parameter_Specifications => New_List (
4511 Make_Parameter_Specification (Loc,
4512 Defining_Identifier => Object_Entity,
4513 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4515 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4517 -- Build procedure body
4520 Make_Defining_Identifier (Loc,
4521 Chars => New_External_Name (Chars (Typ), "Invariant"));
4524 Make_Procedure_Specification (Loc,
4525 Defining_Unit_Name => SId,
4526 Parameter_Specifications => New_List (
4527 Make_Parameter_Specification (Loc,
4528 Defining_Identifier =>
4529 Make_Defining_Identifier (Loc, Object_Name),
4530 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4533 Make_Subprogram_Body (Loc,
4534 Specification => Spec,
4535 Declarations => Empty_List,
4536 Handled_Statement_Sequence =>
4537 Make_Handled_Sequence_Of_Statements (Loc,
4538 Statements => Stmts));
4540 -- Insert procedure declaration and spec at the appropriate points.
4541 -- Skip this if there are no private declarations (that's an error
4542 -- that will be diagnosed elsewhere, and there is no point in having
4543 -- an invariant procedure set if the full declaration is missing).
4545 if Present (Private_Decls) then
4547 -- The spec goes at the end of visible declarations, but they have
4548 -- already been analyzed, so we need to explicitly do the analyze.
4550 Append_To (Visible_Decls, PDecl);
4553 -- The body goes at the end of the private declarations, which we
4554 -- have not analyzed yet, so we do not need to perform an explicit
4555 -- analyze call. We skip this if there are no private declarations
4556 -- (this is an error that will be caught elsewhere);
4558 Append_To (Private_Decls, PBody);
4561 end Build_Invariant_Procedure;
4563 ------------------------------
4564 -- Build_Predicate_Function --
4565 ------------------------------
4567 -- The procedure that is constructed here has the form
4569 -- function typPredicate (Ixxx : typ) return Boolean is
4572 -- exp1 and then exp2 and then ...
4573 -- and then typ1Predicate (typ1 (Ixxx))
4574 -- and then typ2Predicate (typ2 (Ixxx))
4576 -- end typPredicate;
4578 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4579 -- this is the point at which these expressions get analyzed, providing the
4580 -- required delay, and typ1, typ2, are entities from which predicates are
4581 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4582 -- use this function even if checks are off, e.g. for membership tests.
4584 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4585 Loc : constant Source_Ptr := Sloc (Typ);
4592 -- This is the expression for the return statement in the function. It
4593 -- is build by connecting the component predicates with AND THEN.
4595 procedure Add_Call (T : Entity_Id);
4596 -- Includes a call to the predicate function for type T in Expr if T
4597 -- has predicates and Predicate_Function (T) is non-empty.
4599 procedure Add_Predicates;
4600 -- Appends expressions for any Predicate pragmas in the rep item chain
4601 -- Typ to Expr. Note that we look only at items for this exact entity.
4602 -- Inheritance of predicates for the parent type is done by calling the
4603 -- Predicate_Function of the parent type, using Add_Call above.
4605 Object_Name : constant Name_Id := New_Internal_Name ('I');
4606 -- Name for argument of Predicate procedure
4608 Object_Entity : constant Entity_Id :=
4609 Make_Defining_Identifier (Loc, Object_Name);
4610 -- The entity for the spec entity for the argument
4612 Dynamic_Predicate_Present : Boolean := False;
4613 -- Set True if a dynamic predicate is present, results in the entire
4614 -- predicate being considered dynamic even if it looks static
4616 Static_Predicate_Present : Node_Id := Empty;
4617 -- Set to N_Pragma node for a static predicate if one is encountered.
4623 procedure Add_Call (T : Entity_Id) is
4627 if Present (T) and then Present (Predicate_Function (T)) then
4628 Set_Has_Predicates (Typ);
4630 -- Build the call to the predicate function of T
4634 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4636 -- Add call to evolving expression, using AND THEN if needed
4643 Left_Opnd => Relocate_Node (Expr),
4647 -- Output info message on inheritance if required. Note we do not
4648 -- give this information for generic actual types, since it is
4649 -- unwelcome noise in that case in instantiations. We also
4650 -- generally suppress the message in instantiations, and also
4651 -- if it involves internal names.
4653 if Opt.List_Inherited_Aspects
4654 and then not Is_Generic_Actual_Type (Typ)
4655 and then Instantiation_Depth (Sloc (Typ)) = 0
4656 and then not Is_Internal_Name (Chars (T))
4657 and then not Is_Internal_Name (Chars (Typ))
4659 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4660 Error_Msg_Node_2 := T;
4661 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4666 --------------------
4667 -- Add_Predicates --
4668 --------------------
4670 procedure Add_Predicates is
4675 procedure Replace_Type_Reference (N : Node_Id);
4676 -- Replace a single occurrence N of the subtype name with a reference
4677 -- to the formal of the predicate function. N can be an identifier
4678 -- referencing the subtype, or a selected component, representing an
4679 -- appropriately qualified occurrence of the subtype name.
4681 procedure Replace_Type_References is
4682 new Replace_Type_References_Generic (Replace_Type_Reference);
4683 -- Traverse an expression changing every occurrence of an identifier
4684 -- whose name matches the name of the subtype with a reference to
4685 -- the formal parameter of the predicate function.
4687 ----------------------------
4688 -- Replace_Type_Reference --
4689 ----------------------------
4691 procedure Replace_Type_Reference (N : Node_Id) is
4693 Rewrite (N, Make_Identifier (Loc, Object_Name));
4694 Set_Entity (N, Object_Entity);
4696 end Replace_Type_Reference;
4698 -- Start of processing for Add_Predicates
4701 Ritem := First_Rep_Item (Typ);
4702 while Present (Ritem) loop
4703 if Nkind (Ritem) = N_Pragma
4704 and then Pragma_Name (Ritem) = Name_Predicate
4706 if From_Dynamic_Predicate (Ritem) then
4707 Dynamic_Predicate_Present := True;
4708 elsif From_Static_Predicate (Ritem) then
4709 Static_Predicate_Present := Ritem;
4712 -- Acquire arguments
4714 Arg1 := First (Pragma_Argument_Associations (Ritem));
4715 Arg2 := Next (Arg1);
4717 Arg1 := Get_Pragma_Arg (Arg1);
4718 Arg2 := Get_Pragma_Arg (Arg2);
4720 -- See if this predicate pragma is for the current type or for
4721 -- its full view. A predicate on a private completion is placed
4722 -- on the partial view beause this is the visible entity that
4725 if Entity (Arg1) = Typ
4726 or else Full_View (Entity (Arg1)) = Typ
4729 -- We have a match, this entry is for our subtype
4731 -- We need to replace any occurrences of the name of the
4732 -- type with references to the object.
4734 Replace_Type_References (Arg2, Chars (Typ));
4736 -- If this predicate comes from an aspect, find the aspect
4737 -- specification, and replace the saved expression because
4738 -- we need the subtype references replaced for the calls to
4739 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4740 -- and Check_Aspect_At_End_Of_Declarations.
4742 if From_Aspect_Specification (Ritem) then
4747 -- Loop to find corresponding aspect, note that this
4748 -- must be present given the pragma is marked delayed.
4750 Aitem := Next_Rep_Item (Ritem);
4752 if Nkind (Aitem) = N_Aspect_Specification
4753 and then Aspect_Rep_Item (Aitem) = Ritem
4756 (Identifier (Aitem), New_Copy_Tree (Arg2));
4760 Aitem := Next_Rep_Item (Aitem);
4765 -- Now we can add the expression
4768 Expr := Relocate_Node (Arg2);
4770 -- There already was a predicate, so add to it
4775 Left_Opnd => Relocate_Node (Expr),
4776 Right_Opnd => Relocate_Node (Arg2));
4781 Next_Rep_Item (Ritem);
4785 -- Start of processing for Build_Predicate_Function
4788 -- Initialize for construction of statement list
4792 -- Return if already built or if type does not have predicates
4794 if not Has_Predicates (Typ)
4795 or else Present (Predicate_Function (Typ))
4800 -- Add Predicates for the current type
4804 -- Add predicates for ancestor if present
4807 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4809 if Present (Atyp) then
4814 -- If we have predicates, build the function
4816 if Present (Expr) then
4818 -- Build function declaration
4820 pragma Assert (Has_Predicates (Typ));
4822 Make_Defining_Identifier (Loc,
4823 Chars => New_External_Name (Chars (Typ), "Predicate"));
4824 Set_Has_Predicates (SId);
4825 Set_Predicate_Function (Typ, SId);
4828 Make_Function_Specification (Loc,
4829 Defining_Unit_Name => SId,
4830 Parameter_Specifications => New_List (
4831 Make_Parameter_Specification (Loc,
4832 Defining_Identifier => Object_Entity,
4833 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4834 Result_Definition =>
4835 New_Occurrence_Of (Standard_Boolean, Loc));
4837 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4839 -- Build function body
4842 Make_Defining_Identifier (Loc,
4843 Chars => New_External_Name (Chars (Typ), "Predicate"));
4846 Make_Function_Specification (Loc,
4847 Defining_Unit_Name => SId,
4848 Parameter_Specifications => New_List (
4849 Make_Parameter_Specification (Loc,
4850 Defining_Identifier =>
4851 Make_Defining_Identifier (Loc, Object_Name),
4853 New_Occurrence_Of (Typ, Loc))),
4854 Result_Definition =>
4855 New_Occurrence_Of (Standard_Boolean, Loc));
4858 Make_Subprogram_Body (Loc,
4859 Specification => Spec,
4860 Declarations => Empty_List,
4861 Handled_Statement_Sequence =>
4862 Make_Handled_Sequence_Of_Statements (Loc,
4863 Statements => New_List (
4864 Make_Simple_Return_Statement (Loc,
4865 Expression => Expr))));
4867 -- Insert declaration before freeze node and body after
4869 Insert_Before_And_Analyze (N, FDecl);
4870 Insert_After_And_Analyze (N, FBody);
4872 -- Deal with static predicate case
4874 if Ekind_In (Typ, E_Enumeration_Subtype,
4875 E_Modular_Integer_Subtype,
4876 E_Signed_Integer_Subtype)
4877 and then Is_Static_Subtype (Typ)
4878 and then not Dynamic_Predicate_Present
4880 Build_Static_Predicate (Typ, Expr, Object_Name);
4882 if Present (Static_Predicate_Present)
4883 and No (Static_Predicate (Typ))
4886 ("expression does not have required form for "
4887 & "static predicate",
4888 Next (First (Pragma_Argument_Associations
4889 (Static_Predicate_Present))));
4893 end Build_Predicate_Function;
4895 ----------------------------
4896 -- Build_Static_Predicate --
4897 ----------------------------
4899 procedure Build_Static_Predicate
4904 Loc : constant Source_Ptr := Sloc (Expr);
4906 Non_Static : exception;
4907 -- Raised if something non-static is found
4909 Btyp : constant Entity_Id := Base_Type (Typ);
4911 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4912 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4913 -- Low bound and high bound value of base type of Typ
4915 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4916 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4917 -- Low bound and high bound values of static subtype Typ
4922 -- One entry in a Rlist value, a single REnt (range entry) value
4923 -- denotes one range from Lo to Hi. To represent a single value
4924 -- range Lo = Hi = value.
4926 type RList is array (Nat range <>) of REnt;
4927 -- A list of ranges. The ranges are sorted in increasing order,
4928 -- and are disjoint (there is a gap of at least one value between
4929 -- each range in the table). A value is in the set of ranges in
4930 -- Rlist if it lies within one of these ranges
4932 False_Range : constant RList :=
4933 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4934 -- An empty set of ranges represents a range list that can never be
4935 -- satisfied, since there are no ranges in which the value could lie,
4936 -- so it does not lie in any of them. False_Range is a canonical value
4937 -- for this empty set, but general processing should test for an Rlist
4938 -- with length zero (see Is_False predicate), since other null ranges
4939 -- may appear which must be treated as False.
4941 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4942 -- Range representing True, value must be in the base range
4944 function "and" (Left, Right : RList) return RList;
4945 -- And's together two range lists, returning a range list. This is
4946 -- a set intersection operation.
4948 function "or" (Left, Right : RList) return RList;
4949 -- Or's together two range lists, returning a range list. This is a
4950 -- set union operation.
4952 function "not" (Right : RList) return RList;
4953 -- Returns complement of a given range list, i.e. a range list
4954 -- representing all the values in TLo .. THi that are not in the
4955 -- input operand Right.
4957 function Build_Val (V : Uint) return Node_Id;
4958 -- Return an analyzed N_Identifier node referencing this value, suitable
4959 -- for use as an entry in the Static_Predicate list. This node is typed
4960 -- with the base type.
4962 function Build_Range (Lo, Hi : Uint) return Node_Id;
4963 -- Return an analyzed N_Range node referencing this range, suitable
4964 -- for use as an entry in the Static_Predicate list. This node is typed
4965 -- with the base type.
4967 function Get_RList (Exp : Node_Id) return RList;
4968 -- This is a recursive routine that converts the given expression into
4969 -- a list of ranges, suitable for use in building the static predicate.
4971 function Is_False (R : RList) return Boolean;
4972 pragma Inline (Is_False);
4973 -- Returns True if the given range list is empty, and thus represents
4974 -- a False list of ranges that can never be satisfied.
4976 function Is_True (R : RList) return Boolean;
4977 -- Returns True if R trivially represents the True predicate by having
4978 -- a single range from BLo to BHi.
4980 function Is_Type_Ref (N : Node_Id) return Boolean;
4981 pragma Inline (Is_Type_Ref);
4982 -- Returns if True if N is a reference to the type for the predicate in
4983 -- the expression (i.e. if it is an identifier whose Chars field matches
4984 -- the Nam given in the call).
4986 function Lo_Val (N : Node_Id) return Uint;
4987 -- Given static expression or static range from a Static_Predicate list,
4988 -- gets expression value or low bound of range.
4990 function Hi_Val (N : Node_Id) return Uint;
4991 -- Given static expression or static range from a Static_Predicate list,
4992 -- gets expression value of high bound of range.
4994 function Membership_Entry (N : Node_Id) return RList;
4995 -- Given a single membership entry (range, value, or subtype), returns
4996 -- the corresponding range list. Raises Static_Error if not static.
4998 function Membership_Entries (N : Node_Id) return RList;
4999 -- Given an element on an alternatives list of a membership operation,
5000 -- returns the range list corresponding to this entry and all following
5001 -- entries (i.e. returns the "or" of this list of values).
5003 function Stat_Pred (Typ : Entity_Id) return RList;
5004 -- Given a type, if it has a static predicate, then return the predicate
5005 -- as a range list, otherwise raise Non_Static.
5011 function "and" (Left, Right : RList) return RList is
5013 -- First range of result
5015 SLeft : Nat := Left'First;
5016 -- Start of rest of left entries
5018 SRight : Nat := Right'First;
5019 -- Start of rest of right entries
5022 -- If either range is True, return the other
5024 if Is_True (Left) then
5026 elsif Is_True (Right) then
5030 -- If either range is False, return False
5032 if Is_False (Left) or else Is_False (Right) then
5036 -- Loop to remove entries at start that are disjoint, and thus
5037 -- just get discarded from the result entirely.
5040 -- If no operands left in either operand, result is false
5042 if SLeft > Left'Last or else SRight > Right'Last then
5045 -- Discard first left operand entry if disjoint with right
5047 elsif Left (SLeft).Hi < Right (SRight).Lo then
5050 -- Discard first right operand entry if disjoint with left
5052 elsif Right (SRight).Hi < Left (SLeft).Lo then
5053 SRight := SRight + 1;
5055 -- Otherwise we have an overlapping entry
5062 -- Now we have two non-null operands, and first entries overlap.
5063 -- The first entry in the result will be the overlapping part of
5064 -- these two entries.
5066 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
5067 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
5069 -- Now we can remove the entry that ended at a lower value, since
5070 -- its contribution is entirely contained in Fent.
5072 if Left (SLeft).Hi <= Right (SRight).Hi then
5075 SRight := SRight + 1;
5078 -- Compute result by concatenating this first entry with the "and"
5079 -- of the remaining parts of the left and right operands. Note that
5080 -- if either of these is empty, "and" will yield empty, so that we
5081 -- will end up with just Fent, which is what we want in that case.
5084 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
5091 function "not" (Right : RList) return RList is
5093 -- Return True if False range
5095 if Is_False (Right) then
5099 -- Return False if True range
5101 if Is_True (Right) then
5105 -- Here if not trivial case
5108 Result : RList (1 .. Right'Length + 1);
5109 -- May need one more entry for gap at beginning and end
5112 -- Number of entries stored in Result
5117 if Right (Right'First).Lo > TLo then
5119 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
5122 -- Gaps between ranges
5124 for J in Right'First .. Right'Last - 1 loop
5127 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
5132 if Right (Right'Last).Hi < THi then
5134 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
5137 return Result (1 .. Count);
5145 function "or" (Left, Right : RList) return RList is
5147 -- First range of result
5149 SLeft : Nat := Left'First;
5150 -- Start of rest of left entries
5152 SRight : Nat := Right'First;
5153 -- Start of rest of right entries
5156 -- If either range is True, return True
5158 if Is_True (Left) or else Is_True (Right) then
5162 -- If either range is False (empty), return the other
5164 if Is_False (Left) then
5166 elsif Is_False (Right) then
5170 -- Initialize result first entry from left or right operand
5171 -- depending on which starts with the lower range.
5173 if Left (SLeft).Lo < Right (SRight).Lo then
5174 FEnt := Left (SLeft);
5177 FEnt := Right (SRight);
5178 SRight := SRight + 1;
5181 -- This loop eats ranges from left and right operands that
5182 -- are contiguous with the first range we are gathering.
5185 -- Eat first entry in left operand if contiguous or
5186 -- overlapped by gathered first operand of result.
5188 if SLeft <= Left'Last
5189 and then Left (SLeft).Lo <= FEnt.Hi + 1
5191 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
5194 -- Eat first entry in right operand if contiguous or
5195 -- overlapped by gathered right operand of result.
5197 elsif SRight <= Right'Last
5198 and then Right (SRight).Lo <= FEnt.Hi + 1
5200 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
5201 SRight := SRight + 1;
5203 -- All done if no more entries to eat!
5210 -- Obtain result as the first entry we just computed, concatenated
5211 -- to the "or" of the remaining results (if one operand is empty,
5212 -- this will just concatenate with the other
5215 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
5222 function Build_Range (Lo, Hi : Uint) return Node_Id is
5226 return Build_Val (Hi);
5230 Low_Bound => Build_Val (Lo),
5231 High_Bound => Build_Val (Hi));
5232 Set_Etype (Result, Btyp);
5233 Set_Analyzed (Result);
5242 function Build_Val (V : Uint) return Node_Id is
5246 if Is_Enumeration_Type (Typ) then
5247 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
5249 Result := Make_Integer_Literal (Loc, V);
5252 Set_Etype (Result, Btyp);
5253 Set_Is_Static_Expression (Result);
5254 Set_Analyzed (Result);
5262 function Get_RList (Exp : Node_Id) return RList is
5267 -- Static expression can only be true or false
5269 if Is_OK_Static_Expression (Exp) then
5273 if Expr_Value (Exp) = 0 then
5280 -- Otherwise test node type
5288 when N_Op_And | N_And_Then =>
5289 return Get_RList (Left_Opnd (Exp))
5291 Get_RList (Right_Opnd (Exp));
5295 when N_Op_Or | N_Or_Else =>
5296 return Get_RList (Left_Opnd (Exp))
5298 Get_RList (Right_Opnd (Exp));
5303 return not Get_RList (Right_Opnd (Exp));
5305 -- Comparisons of type with static value
5307 when N_Op_Compare =>
5308 -- Type is left operand
5310 if Is_Type_Ref (Left_Opnd (Exp))
5311 and then Is_OK_Static_Expression (Right_Opnd (Exp))
5313 Val := Expr_Value (Right_Opnd (Exp));
5315 -- Typ is right operand
5317 elsif Is_Type_Ref (Right_Opnd (Exp))
5318 and then Is_OK_Static_Expression (Left_Opnd (Exp))
5320 Val := Expr_Value (Left_Opnd (Exp));
5322 -- Invert sense of comparison
5325 when N_Op_Gt => Op := N_Op_Lt;
5326 when N_Op_Lt => Op := N_Op_Gt;
5327 when N_Op_Ge => Op := N_Op_Le;
5328 when N_Op_Le => Op := N_Op_Ge;
5329 when others => null;
5332 -- Other cases are non-static
5338 -- Construct range according to comparison operation
5342 return RList'(1 => REnt'(Val, Val));
5345 return RList'(1 => REnt'(Val, BHi));
5348 return RList'(1 => REnt'(Val + 1, BHi));
5351 return RList'(1 => REnt'(BLo, Val));
5354 return RList'(1 => REnt'(BLo, Val - 1));
5357 return RList'(REnt'(BLo, Val - 1),
5358 REnt'(Val + 1, BHi));
5361 raise Program_Error;
5367 if not Is_Type_Ref (Left_Opnd (Exp)) then
5371 if Present (Right_Opnd (Exp)) then
5372 return Membership_Entry (Right_Opnd (Exp));
5374 return Membership_Entries (First (Alternatives (Exp)));
5377 -- Negative membership (NOT IN)
5380 if not Is_Type_Ref (Left_Opnd (Exp)) then
5384 if Present (Right_Opnd (Exp)) then
5385 return not Membership_Entry (Right_Opnd (Exp));
5387 return not Membership_Entries (First (Alternatives (Exp)));
5390 -- Function call, may be call to static predicate
5392 when N_Function_Call =>
5393 if Is_Entity_Name (Name (Exp)) then
5395 Ent : constant Entity_Id := Entity (Name (Exp));
5397 if Has_Predicates (Ent) then
5398 return Stat_Pred (Etype (First_Formal (Ent)));
5403 -- Other function call cases are non-static
5407 -- Qualified expression, dig out the expression
5409 when N_Qualified_Expression =>
5410 return Get_RList (Expression (Exp));
5415 return (Get_RList (Left_Opnd (Exp))
5416 and not Get_RList (Right_Opnd (Exp)))
5417 or (Get_RList (Right_Opnd (Exp))
5418 and not Get_RList (Left_Opnd (Exp)));
5420 -- Any other node type is non-static
5431 function Hi_Val (N : Node_Id) return Uint is
5433 if Is_Static_Expression (N) then
5434 return Expr_Value (N);
5436 pragma Assert (Nkind (N) = N_Range);
5437 return Expr_Value (High_Bound (N));
5445 function Is_False (R : RList) return Boolean is
5447 return R'Length = 0;
5454 function Is_True (R : RList) return Boolean is
5457 and then R (R'First).Lo = BLo
5458 and then R (R'First).Hi = BHi;
5465 function Is_Type_Ref (N : Node_Id) return Boolean is
5467 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
5474 function Lo_Val (N : Node_Id) return Uint is
5476 if Is_Static_Expression (N) then
5477 return Expr_Value (N);
5479 pragma Assert (Nkind (N) = N_Range);
5480 return Expr_Value (Low_Bound (N));
5484 ------------------------
5485 -- Membership_Entries --
5486 ------------------------
5488 function Membership_Entries (N : Node_Id) return RList is
5490 if No (Next (N)) then
5491 return Membership_Entry (N);
5493 return Membership_Entry (N) or Membership_Entries (Next (N));
5495 end Membership_Entries;
5497 ----------------------
5498 -- Membership_Entry --
5499 ----------------------
5501 function Membership_Entry (N : Node_Id) return RList is
5509 if Nkind (N) = N_Range then
5510 if not Is_Static_Expression (Low_Bound (N))
5512 not Is_Static_Expression (High_Bound (N))
5516 SLo := Expr_Value (Low_Bound (N));
5517 SHi := Expr_Value (High_Bound (N));
5518 return RList'(1 => REnt'(SLo, SHi));
5521 -- Static expression case
5523 elsif Is_Static_Expression (N) then
5524 Val := Expr_Value (N);
5525 return RList'(1 => REnt'(Val, Val));
5527 -- Identifier (other than static expression) case
5529 else pragma Assert (Nkind (N) = N_Identifier);
5533 if Is_Type (Entity (N)) then
5535 -- If type has predicates, process them
5537 if Has_Predicates (Entity (N)) then
5538 return Stat_Pred (Entity (N));
5540 -- For static subtype without predicates, get range
5542 elsif Is_Static_Subtype (Entity (N)) then
5543 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
5544 SHi := Expr_Value (Type_High_Bound (Entity (N)));
5545 return RList'(1 => REnt'(SLo, SHi));
5547 -- Any other type makes us non-static
5553 -- Any other kind of identifier in predicate (e.g. a non-static
5554 -- expression value) means this is not a static predicate.
5560 end Membership_Entry;
5566 function Stat_Pred (Typ : Entity_Id) return RList is
5568 -- Not static if type does not have static predicates
5570 if not Has_Predicates (Typ)
5571 or else No (Static_Predicate (Typ))
5576 -- Otherwise we convert the predicate list to a range list
5579 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5583 P := First (Static_Predicate (Typ));
5584 for J in Result'Range loop
5585 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5593 -- Start of processing for Build_Static_Predicate
5596 -- Now analyze the expression to see if it is a static predicate
5599 Ranges : constant RList := Get_RList (Expr);
5600 -- Range list from expression if it is static
5605 -- Convert range list into a form for the static predicate. In the
5606 -- Ranges array, we just have raw ranges, these must be converted
5607 -- to properly typed and analyzed static expressions or range nodes.
5609 -- Note: here we limit ranges to the ranges of the subtype, so that
5610 -- a predicate is always false for values outside the subtype. That
5611 -- seems fine, such values are invalid anyway, and considering them
5612 -- to fail the predicate seems allowed and friendly, and furthermore
5613 -- simplifies processing for case statements and loops.
5617 for J in Ranges'Range loop
5619 Lo : Uint := Ranges (J).Lo;
5620 Hi : Uint := Ranges (J).Hi;
5623 -- Ignore completely out of range entry
5625 if Hi < TLo or else Lo > THi then
5628 -- Otherwise process entry
5631 -- Adjust out of range value to subtype range
5641 -- Convert range into required form
5644 Append_To (Plist, Build_Val (Lo));
5646 Append_To (Plist, Build_Range (Lo, Hi));
5652 -- Processing was successful and all entries were static, so now we
5653 -- can store the result as the predicate list.
5655 Set_Static_Predicate (Typ, Plist);
5657 -- The processing for static predicates put the expression into
5658 -- canonical form as a series of ranges. It also eliminated
5659 -- duplicates and collapsed and combined ranges. We might as well
5660 -- replace the alternatives list of the right operand of the
5661 -- membership test with the static predicate list, which will
5662 -- usually be more efficient.
5665 New_Alts : constant List_Id := New_List;
5670 Old_Node := First (Plist);
5671 while Present (Old_Node) loop
5672 New_Node := New_Copy (Old_Node);
5674 if Nkind (New_Node) = N_Range then
5675 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5676 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5679 Append_To (New_Alts, New_Node);
5683 -- If empty list, replace by False
5685 if Is_Empty_List (New_Alts) then
5686 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5688 -- Else replace by set membership test
5693 Left_Opnd => Make_Identifier (Loc, Nam),
5694 Right_Opnd => Empty,
5695 Alternatives => New_Alts));
5697 -- Resolve new expression in function context
5699 Install_Formals (Predicate_Function (Typ));
5700 Push_Scope (Predicate_Function (Typ));
5701 Analyze_And_Resolve (Expr, Standard_Boolean);
5707 -- If non-static, return doing nothing
5712 end Build_Static_Predicate;
5714 -----------------------------------------
5715 -- Check_Aspect_At_End_Of_Declarations --
5716 -----------------------------------------
5718 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5719 Ent : constant Entity_Id := Entity (ASN);
5720 Ident : constant Node_Id := Identifier (ASN);
5722 Freeze_Expr : constant Node_Id := Expression (ASN);
5723 -- Expression from call to Check_Aspect_At_Freeze_Point
5725 End_Decl_Expr : constant Node_Id := Entity (Ident);
5726 -- Expression to be analyzed at end of declarations
5728 T : constant Entity_Id := Etype (Freeze_Expr);
5729 -- Type required for preanalyze call
5731 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5734 -- Set False if error
5736 -- On entry to this procedure, Entity (Ident) contains a copy of the
5737 -- original expression from the aspect, saved for this purpose, and
5738 -- but Expression (Ident) is a preanalyzed copy of the expression,
5739 -- preanalyzed just after the freeze point.
5742 -- Case of stream attributes, just have to compare entities
5744 if A_Id = Aspect_Input or else
5745 A_Id = Aspect_Output or else
5746 A_Id = Aspect_Read or else
5749 Analyze (End_Decl_Expr);
5750 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5752 elsif A_Id = Aspect_Variable_Indexing or else
5753 A_Id = Aspect_Constant_Indexing or else
5754 A_Id = Aspect_Default_Iterator or else
5755 A_Id = Aspect_Iterator_Element
5757 Analyze (End_Decl_Expr);
5758 Analyze (Aspect_Rep_Item (ASN));
5760 -- If the end of declarations comes before any other freeze
5761 -- point, the Freeze_Expr is not analyzed: no check needed.
5764 Analyzed (Freeze_Expr)
5765 and then not In_Instance
5766 and then Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5771 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5772 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5775 -- Output error message if error
5779 ("visibility of aspect for& changes after freeze point",
5782 ("?info: & is frozen here, aspects evaluated at this point",
5783 Freeze_Node (Ent), Ent);
5785 end Check_Aspect_At_End_Of_Declarations;
5787 ----------------------------------
5788 -- Check_Aspect_At_Freeze_Point --
5789 ----------------------------------
5791 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5792 Ident : constant Node_Id := Identifier (ASN);
5793 -- Identifier (use Entity field to save expression)
5796 -- Type required for preanalyze call
5798 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5801 -- On entry to this procedure, Entity (Ident) contains a copy of the
5802 -- original expression from the aspect, saved for this purpose.
5804 -- On exit from this procedure Entity (Ident) is unchanged, still
5805 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5806 -- of the expression, preanalyzed just after the freeze point.
5808 -- Make a copy of the expression to be preanalyed
5810 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5812 -- Find type for preanalyze call
5816 -- No_Aspect should be impossible
5819 raise Program_Error;
5821 -- Library unit aspects should be impossible (never delayed)
5823 when Library_Unit_Aspects =>
5824 raise Program_Error;
5826 -- Aspects taking an optional boolean argument. Should be impossible
5827 -- since these are never delayed.
5829 when Boolean_Aspects =>
5830 raise Program_Error;
5832 -- Test_Case aspect applies to entries and subprograms, hence should
5833 -- never be delayed.
5835 when Aspect_Test_Case =>
5836 raise Program_Error;
5838 when Aspect_Attach_Handler =>
5839 T := RTE (RE_Interrupt_ID);
5841 -- Default_Value is resolved with the type entity in question
5843 when Aspect_Default_Value =>
5846 -- Default_Component_Value is resolved with the component type
5848 when Aspect_Default_Component_Value =>
5849 T := Component_Type (Entity (ASN));
5851 -- Aspects corresponding to attribute definition clauses
5853 when Aspect_Address =>
5854 T := RTE (RE_Address);
5856 when Aspect_Bit_Order =>
5857 T := RTE (RE_Bit_Order);
5859 when Aspect_External_Tag =>
5860 T := Standard_String;
5862 when Aspect_Priority | Aspect_Interrupt_Priority =>
5863 T := Standard_Integer;
5865 when Aspect_Small =>
5866 T := Universal_Real;
5868 when Aspect_Storage_Pool =>
5869 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5871 when Aspect_Alignment |
5872 Aspect_Component_Size |
5873 Aspect_Machine_Radix |
5874 Aspect_Object_Size |
5876 Aspect_Storage_Size |
5877 Aspect_Stream_Size |
5878 Aspect_Value_Size =>
5881 -- Stream attribute. Special case, the expression is just an entity
5882 -- that does not need any resolution, so just analyze.
5888 Analyze (Expression (ASN));
5891 -- Same for Iterator aspects, where the expression is a function
5892 -- name. Legality rules are checked separately.
5894 when Aspect_Constant_Indexing |
5895 Aspect_Default_Iterator |
5896 Aspect_Iterator_Element |
5897 Aspect_Implicit_Dereference |
5898 Aspect_Variable_Indexing =>
5899 Analyze (Expression (ASN));
5902 -- Suppress/Unsuppress/Warnings should never be delayed
5904 when Aspect_Suppress |
5907 raise Program_Error;
5909 -- Pre/Post/Invariant/Predicate take boolean expressions
5911 when Aspect_Dynamic_Predicate |
5914 Aspect_Precondition |
5916 Aspect_Postcondition |
5918 Aspect_Static_Predicate |
5919 Aspect_Type_Invariant =>
5920 T := Standard_Boolean;
5923 -- Do the preanalyze call
5925 Preanalyze_Spec_Expression (Expression (ASN), T);
5926 end Check_Aspect_At_Freeze_Point;
5928 -----------------------------------
5929 -- Check_Constant_Address_Clause --
5930 -----------------------------------
5932 procedure Check_Constant_Address_Clause
5936 procedure Check_At_Constant_Address (Nod : Node_Id);
5937 -- Checks that the given node N represents a name whose 'Address is
5938 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5939 -- address value is the same at the point of declaration of U_Ent and at
5940 -- the time of elaboration of the address clause.
5942 procedure Check_Expr_Constants (Nod : Node_Id);
5943 -- Checks that Nod meets the requirements for a constant address clause
5944 -- in the sense of the enclosing procedure.
5946 procedure Check_List_Constants (Lst : List_Id);
5947 -- Check that all elements of list Lst meet the requirements for a
5948 -- constant address clause in the sense of the enclosing procedure.
5950 -------------------------------
5951 -- Check_At_Constant_Address --
5952 -------------------------------
5954 procedure Check_At_Constant_Address (Nod : Node_Id) is
5956 if Is_Entity_Name (Nod) then
5957 if Present (Address_Clause (Entity ((Nod)))) then
5959 ("invalid address clause for initialized object &!",
5962 ("address for& cannot" &
5963 " depend on another address clause! (RM 13.1(22))!",
5966 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
5967 and then Sloc (U_Ent) < Sloc (Entity (Nod))
5970 ("invalid address clause for initialized object &!",
5972 Error_Msg_Node_2 := U_Ent;
5974 ("\& must be defined before & (RM 13.1(22))!",
5978 elsif Nkind (Nod) = N_Selected_Component then
5980 T : constant Entity_Id := Etype (Prefix (Nod));
5983 if (Is_Record_Type (T)
5984 and then Has_Discriminants (T))
5987 and then Is_Record_Type (Designated_Type (T))
5988 and then Has_Discriminants (Designated_Type (T)))
5991 ("invalid address clause for initialized object &!",
5994 ("\address cannot depend on component" &
5995 " of discriminated record (RM 13.1(22))!",
5998 Check_At_Constant_Address (Prefix (Nod));
6002 elsif Nkind (Nod) = N_Indexed_Component then
6003 Check_At_Constant_Address (Prefix (Nod));
6004 Check_List_Constants (Expressions (Nod));
6007 Check_Expr_Constants (Nod);
6009 end Check_At_Constant_Address;
6011 --------------------------
6012 -- Check_Expr_Constants --
6013 --------------------------
6015 procedure Check_Expr_Constants (Nod : Node_Id) is
6016 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
6017 Ent : Entity_Id := Empty;
6020 if Nkind (Nod) in N_Has_Etype
6021 and then Etype (Nod) = Any_Type
6027 when N_Empty | N_Error =>
6030 when N_Identifier | N_Expanded_Name =>
6031 Ent := Entity (Nod);
6033 -- We need to look at the original node if it is different
6034 -- from the node, since we may have rewritten things and
6035 -- substituted an identifier representing the rewrite.
6037 if Original_Node (Nod) /= Nod then
6038 Check_Expr_Constants (Original_Node (Nod));
6040 -- If the node is an object declaration without initial
6041 -- value, some code has been expanded, and the expression
6042 -- is not constant, even if the constituents might be
6043 -- acceptable, as in A'Address + offset.
6045 if Ekind (Ent) = E_Variable
6047 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
6049 No (Expression (Declaration_Node (Ent)))
6052 ("invalid address clause for initialized object &!",
6055 -- If entity is constant, it may be the result of expanding
6056 -- a check. We must verify that its declaration appears
6057 -- before the object in question, else we also reject the
6060 elsif Ekind (Ent) = E_Constant
6061 and then In_Same_Source_Unit (Ent, U_Ent)
6062 and then Sloc (Ent) > Loc_U_Ent
6065 ("invalid address clause for initialized object &!",
6072 -- Otherwise look at the identifier and see if it is OK
6074 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
6075 or else Is_Type (Ent)
6080 Ekind (Ent) = E_Constant
6082 Ekind (Ent) = E_In_Parameter
6084 -- This is the case where we must have Ent defined before
6085 -- U_Ent. Clearly if they are in different units this
6086 -- requirement is met since the unit containing Ent is
6087 -- already processed.
6089 if not In_Same_Source_Unit (Ent, U_Ent) then
6092 -- Otherwise location of Ent must be before the location
6093 -- of U_Ent, that's what prior defined means.
6095 elsif Sloc (Ent) < Loc_U_Ent then
6100 ("invalid address clause for initialized object &!",
6102 Error_Msg_Node_2 := U_Ent;
6104 ("\& must be defined before & (RM 13.1(22))!",
6108 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
6109 Check_Expr_Constants (Original_Node (Nod));
6113 ("invalid address clause for initialized object &!",
6116 if Comes_From_Source (Ent) then
6118 ("\reference to variable& not allowed"
6119 & " (RM 13.1(22))!", Nod, Ent);
6122 ("non-static expression not allowed"
6123 & " (RM 13.1(22))!", Nod);
6127 when N_Integer_Literal =>
6129 -- If this is a rewritten unchecked conversion, in a system
6130 -- where Address is an integer type, always use the base type
6131 -- for a literal value. This is user-friendly and prevents
6132 -- order-of-elaboration issues with instances of unchecked
6135 if Nkind (Original_Node (Nod)) = N_Function_Call then
6136 Set_Etype (Nod, Base_Type (Etype (Nod)));
6139 when N_Real_Literal |
6141 N_Character_Literal =>
6145 Check_Expr_Constants (Low_Bound (Nod));
6146 Check_Expr_Constants (High_Bound (Nod));
6148 when N_Explicit_Dereference =>
6149 Check_Expr_Constants (Prefix (Nod));
6151 when N_Indexed_Component =>
6152 Check_Expr_Constants (Prefix (Nod));
6153 Check_List_Constants (Expressions (Nod));
6156 Check_Expr_Constants (Prefix (Nod));
6157 Check_Expr_Constants (Discrete_Range (Nod));
6159 when N_Selected_Component =>
6160 Check_Expr_Constants (Prefix (Nod));
6162 when N_Attribute_Reference =>
6163 if Attribute_Name (Nod) = Name_Address
6165 Attribute_Name (Nod) = Name_Access
6167 Attribute_Name (Nod) = Name_Unchecked_Access
6169 Attribute_Name (Nod) = Name_Unrestricted_Access
6171 Check_At_Constant_Address (Prefix (Nod));
6174 Check_Expr_Constants (Prefix (Nod));
6175 Check_List_Constants (Expressions (Nod));
6179 Check_List_Constants (Component_Associations (Nod));
6180 Check_List_Constants (Expressions (Nod));
6182 when N_Component_Association =>
6183 Check_Expr_Constants (Expression (Nod));
6185 when N_Extension_Aggregate =>
6186 Check_Expr_Constants (Ancestor_Part (Nod));
6187 Check_List_Constants (Component_Associations (Nod));
6188 Check_List_Constants (Expressions (Nod));
6193 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
6194 Check_Expr_Constants (Left_Opnd (Nod));
6195 Check_Expr_Constants (Right_Opnd (Nod));
6198 Check_Expr_Constants (Right_Opnd (Nod));
6200 when N_Type_Conversion |
6201 N_Qualified_Expression |
6203 Check_Expr_Constants (Expression (Nod));
6205 when N_Unchecked_Type_Conversion =>
6206 Check_Expr_Constants (Expression (Nod));
6208 -- If this is a rewritten unchecked conversion, subtypes in
6209 -- this node are those created within the instance. To avoid
6210 -- order of elaboration issues, replace them with their base
6211 -- types. Note that address clauses can cause order of
6212 -- elaboration problems because they are elaborated by the
6213 -- back-end at the point of definition, and may mention
6214 -- entities declared in between (as long as everything is
6215 -- static). It is user-friendly to allow unchecked conversions
6218 if Nkind (Original_Node (Nod)) = N_Function_Call then
6219 Set_Etype (Expression (Nod),
6220 Base_Type (Etype (Expression (Nod))));
6221 Set_Etype (Nod, Base_Type (Etype (Nod)));
6224 when N_Function_Call =>
6225 if not Is_Pure (Entity (Name (Nod))) then
6227 ("invalid address clause for initialized object &!",
6231 ("\function & is not pure (RM 13.1(22))!",
6232 Nod, Entity (Name (Nod)));
6235 Check_List_Constants (Parameter_Associations (Nod));
6238 when N_Parameter_Association =>
6239 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
6243 ("invalid address clause for initialized object &!",
6246 ("\must be constant defined before& (RM 13.1(22))!",
6249 end Check_Expr_Constants;
6251 --------------------------
6252 -- Check_List_Constants --
6253 --------------------------
6255 procedure Check_List_Constants (Lst : List_Id) is
6259 if Present (Lst) then
6260 Nod1 := First (Lst);
6261 while Present (Nod1) loop
6262 Check_Expr_Constants (Nod1);
6266 end Check_List_Constants;
6268 -- Start of processing for Check_Constant_Address_Clause
6271 -- If rep_clauses are to be ignored, no need for legality checks. In
6272 -- particular, no need to pester user about rep clauses that violate
6273 -- the rule on constant addresses, given that these clauses will be
6274 -- removed by Freeze before they reach the back end.
6276 if not Ignore_Rep_Clauses then
6277 Check_Expr_Constants (Expr);
6279 end Check_Constant_Address_Clause;
6281 ----------------------------------------
6282 -- Check_Record_Representation_Clause --
6283 ----------------------------------------
6285 procedure Check_Record_Representation_Clause (N : Node_Id) is
6286 Loc : constant Source_Ptr := Sloc (N);
6287 Ident : constant Node_Id := Identifier (N);
6288 Rectype : Entity_Id;
6293 Hbit : Uint := Uint_0;
6297 Max_Bit_So_Far : Uint;
6298 -- Records the maximum bit position so far. If all field positions
6299 -- are monotonically increasing, then we can skip the circuit for
6300 -- checking for overlap, since no overlap is possible.
6302 Tagged_Parent : Entity_Id := Empty;
6303 -- This is set in the case of a derived tagged type for which we have
6304 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
6305 -- positioned by record representation clauses). In this case we must
6306 -- check for overlap between components of this tagged type, and the
6307 -- components of its parent. Tagged_Parent will point to this parent
6308 -- type. For all other cases Tagged_Parent is left set to Empty.
6310 Parent_Last_Bit : Uint;
6311 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
6312 -- last bit position for any field in the parent type. We only need to
6313 -- check overlap for fields starting below this point.
6315 Overlap_Check_Required : Boolean;
6316 -- Used to keep track of whether or not an overlap check is required
6318 Overlap_Detected : Boolean := False;
6319 -- Set True if an overlap is detected
6321 Ccount : Natural := 0;
6322 -- Number of component clauses in record rep clause
6324 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
6325 -- Given two entities for record components or discriminants, checks
6326 -- if they have overlapping component clauses and issues errors if so.
6328 procedure Find_Component;
6329 -- Finds component entity corresponding to current component clause (in
6330 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
6331 -- start/stop bits for the field. If there is no matching component or
6332 -- if the matching component does not have a component clause, then
6333 -- that's an error and Comp is set to Empty, but no error message is
6334 -- issued, since the message was already given. Comp is also set to
6335 -- Empty if the current "component clause" is in fact a pragma.
6337 -----------------------------
6338 -- Check_Component_Overlap --
6339 -----------------------------
6341 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
6342 CC1 : constant Node_Id := Component_Clause (C1_Ent);
6343 CC2 : constant Node_Id := Component_Clause (C2_Ent);
6346 if Present (CC1) and then Present (CC2) then
6348 -- Exclude odd case where we have two tag fields in the same
6349 -- record, both at location zero. This seems a bit strange, but
6350 -- it seems to happen in some circumstances, perhaps on an error.
6352 if Chars (C1_Ent) = Name_uTag
6354 Chars (C2_Ent) = Name_uTag
6359 -- Here we check if the two fields overlap
6362 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
6363 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
6364 E1 : constant Uint := S1 + Esize (C1_Ent);
6365 E2 : constant Uint := S2 + Esize (C2_Ent);
6368 if E2 <= S1 or else E1 <= S2 then
6371 Error_Msg_Node_2 := Component_Name (CC2);
6372 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6373 Error_Msg_Node_1 := Component_Name (CC1);
6375 ("component& overlaps & #", Component_Name (CC1));
6376 Overlap_Detected := True;
6380 end Check_Component_Overlap;
6382 --------------------
6383 -- Find_Component --
6384 --------------------
6386 procedure Find_Component is
6388 procedure Search_Component (R : Entity_Id);
6389 -- Search components of R for a match. If found, Comp is set.
6391 ----------------------
6392 -- Search_Component --
6393 ----------------------
6395 procedure Search_Component (R : Entity_Id) is
6397 Comp := First_Component_Or_Discriminant (R);
6398 while Present (Comp) loop
6400 -- Ignore error of attribute name for component name (we
6401 -- already gave an error message for this, so no need to
6404 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
6407 exit when Chars (Comp) = Chars (Component_Name (CC));
6410 Next_Component_Or_Discriminant (Comp);
6412 end Search_Component;
6414 -- Start of processing for Find_Component
6417 -- Return with Comp set to Empty if we have a pragma
6419 if Nkind (CC) = N_Pragma then
6424 -- Search current record for matching component
6426 Search_Component (Rectype);
6428 -- If not found, maybe component of base type that is absent from
6429 -- statically constrained first subtype.
6432 Search_Component (Base_Type (Rectype));
6435 -- If no component, or the component does not reference the component
6436 -- clause in question, then there was some previous error for which
6437 -- we already gave a message, so just return with Comp Empty.
6440 or else Component_Clause (Comp) /= CC
6444 -- Normal case where we have a component clause
6447 Fbit := Component_Bit_Offset (Comp);
6448 Lbit := Fbit + Esize (Comp) - 1;
6452 -- Start of processing for Check_Record_Representation_Clause
6456 Rectype := Entity (Ident);
6458 if Rectype = Any_Type then
6461 Rectype := Underlying_Type (Rectype);
6464 -- See if we have a fully repped derived tagged type
6467 PS : constant Entity_Id := Parent_Subtype (Rectype);
6470 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
6471 Tagged_Parent := PS;
6473 -- Find maximum bit of any component of the parent type
6475 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
6476 Pcomp := First_Entity (Tagged_Parent);
6477 while Present (Pcomp) loop
6478 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
6479 if Component_Bit_Offset (Pcomp) /= No_Uint
6480 and then Known_Static_Esize (Pcomp)
6485 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
6488 Next_Entity (Pcomp);
6494 -- All done if no component clauses
6496 CC := First (Component_Clauses (N));
6502 -- If a tag is present, then create a component clause that places it
6503 -- at the start of the record (otherwise gigi may place it after other
6504 -- fields that have rep clauses).
6506 Fent := First_Entity (Rectype);
6508 if Nkind (Fent) = N_Defining_Identifier
6509 and then Chars (Fent) = Name_uTag
6511 Set_Component_Bit_Offset (Fent, Uint_0);
6512 Set_Normalized_Position (Fent, Uint_0);
6513 Set_Normalized_First_Bit (Fent, Uint_0);
6514 Set_Normalized_Position_Max (Fent, Uint_0);
6515 Init_Esize (Fent, System_Address_Size);
6517 Set_Component_Clause (Fent,
6518 Make_Component_Clause (Loc,
6519 Component_Name => Make_Identifier (Loc, Name_uTag),
6521 Position => Make_Integer_Literal (Loc, Uint_0),
6522 First_Bit => Make_Integer_Literal (Loc, Uint_0),
6524 Make_Integer_Literal (Loc,
6525 UI_From_Int (System_Address_Size))));
6527 Ccount := Ccount + 1;
6530 Max_Bit_So_Far := Uint_Minus_1;
6531 Overlap_Check_Required := False;
6533 -- Process the component clauses
6535 while Present (CC) loop
6538 if Present (Comp) then
6539 Ccount := Ccount + 1;
6541 -- We need a full overlap check if record positions non-monotonic
6543 if Fbit <= Max_Bit_So_Far then
6544 Overlap_Check_Required := True;
6547 Max_Bit_So_Far := Lbit;
6549 -- Check bit position out of range of specified size
6551 if Has_Size_Clause (Rectype)
6552 and then RM_Size (Rectype) <= Lbit
6555 ("bit number out of range of specified size",
6558 -- Check for overlap with tag field
6561 if Is_Tagged_Type (Rectype)
6562 and then Fbit < System_Address_Size
6565 ("component overlaps tag field of&",
6566 Component_Name (CC), Rectype);
6567 Overlap_Detected := True;
6575 -- Check parent overlap if component might overlap parent field
6577 if Present (Tagged_Parent)
6578 and then Fbit <= Parent_Last_Bit
6580 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
6581 while Present (Pcomp) loop
6582 if not Is_Tag (Pcomp)
6583 and then Chars (Pcomp) /= Name_uParent
6585 Check_Component_Overlap (Comp, Pcomp);
6588 Next_Component_Or_Discriminant (Pcomp);
6596 -- Now that we have processed all the component clauses, check for
6597 -- overlap. We have to leave this till last, since the components can
6598 -- appear in any arbitrary order in the representation clause.
6600 -- We do not need this check if all specified ranges were monotonic,
6601 -- as recorded by Overlap_Check_Required being False at this stage.
6603 -- This first section checks if there are any overlapping entries at
6604 -- all. It does this by sorting all entries and then seeing if there are
6605 -- any overlaps. If there are none, then that is decisive, but if there
6606 -- are overlaps, they may still be OK (they may result from fields in
6607 -- different variants).
6609 if Overlap_Check_Required then
6610 Overlap_Check1 : declare
6612 OC_Fbit : array (0 .. Ccount) of Uint;
6613 -- First-bit values for component clauses, the value is the offset
6614 -- of the first bit of the field from start of record. The zero
6615 -- entry is for use in sorting.
6617 OC_Lbit : array (0 .. Ccount) of Uint;
6618 -- Last-bit values for component clauses, the value is the offset
6619 -- of the last bit of the field from start of record. The zero
6620 -- entry is for use in sorting.
6622 OC_Count : Natural := 0;
6623 -- Count of entries in OC_Fbit and OC_Lbit
6625 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6626 -- Compare routine for Sort
6628 procedure OC_Move (From : Natural; To : Natural);
6629 -- Move routine for Sort
6631 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6637 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6639 return OC_Fbit (Op1) < OC_Fbit (Op2);
6646 procedure OC_Move (From : Natural; To : Natural) is
6648 OC_Fbit (To) := OC_Fbit (From);
6649 OC_Lbit (To) := OC_Lbit (From);
6652 -- Start of processing for Overlap_Check
6655 CC := First (Component_Clauses (N));
6656 while Present (CC) loop
6658 -- Exclude component clause already marked in error
6660 if not Error_Posted (CC) then
6663 if Present (Comp) then
6664 OC_Count := OC_Count + 1;
6665 OC_Fbit (OC_Count) := Fbit;
6666 OC_Lbit (OC_Count) := Lbit;
6673 Sorting.Sort (OC_Count);
6675 Overlap_Check_Required := False;
6676 for J in 1 .. OC_Count - 1 loop
6677 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6678 Overlap_Check_Required := True;
6685 -- If Overlap_Check_Required is still True, then we have to do the full
6686 -- scale overlap check, since we have at least two fields that do
6687 -- overlap, and we need to know if that is OK since they are in
6688 -- different variant, or whether we have a definite problem.
6690 if Overlap_Check_Required then
6691 Overlap_Check2 : declare
6692 C1_Ent, C2_Ent : Entity_Id;
6693 -- Entities of components being checked for overlap
6696 -- Component_List node whose Component_Items are being checked
6699 -- Component declaration for component being checked
6702 C1_Ent := First_Entity (Base_Type (Rectype));
6704 -- Loop through all components in record. For each component check
6705 -- for overlap with any of the preceding elements on the component
6706 -- list containing the component and also, if the component is in
6707 -- a variant, check against components outside the case structure.
6708 -- This latter test is repeated recursively up the variant tree.
6710 Main_Component_Loop : while Present (C1_Ent) loop
6711 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6712 goto Continue_Main_Component_Loop;
6715 -- Skip overlap check if entity has no declaration node. This
6716 -- happens with discriminants in constrained derived types.
6717 -- Possibly we are missing some checks as a result, but that
6718 -- does not seem terribly serious.
6720 if No (Declaration_Node (C1_Ent)) then
6721 goto Continue_Main_Component_Loop;
6724 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6726 -- Loop through component lists that need checking. Check the
6727 -- current component list and all lists in variants above us.
6729 Component_List_Loop : loop
6731 -- If derived type definition, go to full declaration
6732 -- If at outer level, check discriminants if there are any.
6734 if Nkind (Clist) = N_Derived_Type_Definition then
6735 Clist := Parent (Clist);
6738 -- Outer level of record definition, check discriminants
6740 if Nkind_In (Clist, N_Full_Type_Declaration,
6741 N_Private_Type_Declaration)
6743 if Has_Discriminants (Defining_Identifier (Clist)) then
6745 First_Discriminant (Defining_Identifier (Clist));
6746 while Present (C2_Ent) loop
6747 exit when C1_Ent = C2_Ent;
6748 Check_Component_Overlap (C1_Ent, C2_Ent);
6749 Next_Discriminant (C2_Ent);
6753 -- Record extension case
6755 elsif Nkind (Clist) = N_Derived_Type_Definition then
6758 -- Otherwise check one component list
6761 Citem := First (Component_Items (Clist));
6762 while Present (Citem) loop
6763 if Nkind (Citem) = N_Component_Declaration then
6764 C2_Ent := Defining_Identifier (Citem);
6765 exit when C1_Ent = C2_Ent;
6766 Check_Component_Overlap (C1_Ent, C2_Ent);
6773 -- Check for variants above us (the parent of the Clist can
6774 -- be a variant, in which case its parent is a variant part,
6775 -- and the parent of the variant part is a component list
6776 -- whose components must all be checked against the current
6777 -- component for overlap).
6779 if Nkind (Parent (Clist)) = N_Variant then
6780 Clist := Parent (Parent (Parent (Clist)));
6782 -- Check for possible discriminant part in record, this
6783 -- is treated essentially as another level in the
6784 -- recursion. For this case the parent of the component
6785 -- list is the record definition, and its parent is the
6786 -- full type declaration containing the discriminant
6789 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6790 Clist := Parent (Parent ((Clist)));
6792 -- If neither of these two cases, we are at the top of
6796 exit Component_List_Loop;
6798 end loop Component_List_Loop;
6800 <<Continue_Main_Component_Loop>>
6801 Next_Entity (C1_Ent);
6803 end loop Main_Component_Loop;
6807 -- The following circuit deals with warning on record holes (gaps). We
6808 -- skip this check if overlap was detected, since it makes sense for the
6809 -- programmer to fix this illegality before worrying about warnings.
6811 if not Overlap_Detected and Warn_On_Record_Holes then
6812 Record_Hole_Check : declare
6813 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6814 -- Full declaration of record type
6816 procedure Check_Component_List
6820 -- Check component list CL for holes. The starting bit should be
6821 -- Sbit. which is zero for the main record component list and set
6822 -- appropriately for recursive calls for variants. DS is set to
6823 -- a list of discriminant specifications to be included in the
6824 -- consideration of components. It is No_List if none to consider.
6826 --------------------------
6827 -- Check_Component_List --
6828 --------------------------
6830 procedure Check_Component_List
6838 Compl := Integer (List_Length (Component_Items (CL)));
6840 if DS /= No_List then
6841 Compl := Compl + Integer (List_Length (DS));
6845 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6846 -- Gather components (zero entry is for sort routine)
6848 Ncomps : Natural := 0;
6849 -- Number of entries stored in Comps (starting at Comps (1))
6852 -- One component item or discriminant specification
6855 -- Starting bit for next component
6863 function Lt (Op1, Op2 : Natural) return Boolean;
6864 -- Compare routine for Sort
6866 procedure Move (From : Natural; To : Natural);
6867 -- Move routine for Sort
6869 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6875 function Lt (Op1, Op2 : Natural) return Boolean is
6877 return Component_Bit_Offset (Comps (Op1))
6879 Component_Bit_Offset (Comps (Op2));
6886 procedure Move (From : Natural; To : Natural) is
6888 Comps (To) := Comps (From);
6892 -- Gather discriminants into Comp
6894 if DS /= No_List then
6895 Citem := First (DS);
6896 while Present (Citem) loop
6897 if Nkind (Citem) = N_Discriminant_Specification then
6899 Ent : constant Entity_Id :=
6900 Defining_Identifier (Citem);
6902 if Ekind (Ent) = E_Discriminant then
6903 Ncomps := Ncomps + 1;
6904 Comps (Ncomps) := Ent;
6913 -- Gather component entities into Comp
6915 Citem := First (Component_Items (CL));
6916 while Present (Citem) loop
6917 if Nkind (Citem) = N_Component_Declaration then
6918 Ncomps := Ncomps + 1;
6919 Comps (Ncomps) := Defining_Identifier (Citem);
6925 -- Now sort the component entities based on the first bit.
6926 -- Note we already know there are no overlapping components.
6928 Sorting.Sort (Ncomps);
6930 -- Loop through entries checking for holes
6933 for J in 1 .. Ncomps loop
6935 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6937 if Error_Msg_Uint_1 > 0 then
6939 ("?^-bit gap before component&",
6940 Component_Name (Component_Clause (CEnt)), CEnt);
6943 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
6946 -- Process variant parts recursively if present
6948 if Present (Variant_Part (CL)) then
6949 Variant := First (Variants (Variant_Part (CL)));
6950 while Present (Variant) loop
6951 Check_Component_List
6952 (Component_List (Variant), Nbit, No_List);
6957 end Check_Component_List;
6959 -- Start of processing for Record_Hole_Check
6966 if Is_Tagged_Type (Rectype) then
6967 Sbit := UI_From_Int (System_Address_Size);
6972 if Nkind (Decl) = N_Full_Type_Declaration
6973 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6975 Check_Component_List
6976 (Component_List (Type_Definition (Decl)),
6978 Discriminant_Specifications (Decl));
6981 end Record_Hole_Check;
6984 -- For records that have component clauses for all components, and whose
6985 -- size is less than or equal to 32, we need to know the size in the
6986 -- front end to activate possible packed array processing where the
6987 -- component type is a record.
6989 -- At this stage Hbit + 1 represents the first unused bit from all the
6990 -- component clauses processed, so if the component clauses are
6991 -- complete, then this is the length of the record.
6993 -- For records longer than System.Storage_Unit, and for those where not
6994 -- all components have component clauses, the back end determines the
6995 -- length (it may for example be appropriate to round up the size
6996 -- to some convenient boundary, based on alignment considerations, etc).
6998 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
7000 -- Nothing to do if at least one component has no component clause
7002 Comp := First_Component_Or_Discriminant (Rectype);
7003 while Present (Comp) loop
7004 exit when No (Component_Clause (Comp));
7005 Next_Component_Or_Discriminant (Comp);
7008 -- If we fall out of loop, all components have component clauses
7009 -- and so we can set the size to the maximum value.
7012 Set_RM_Size (Rectype, Hbit + 1);
7015 end Check_Record_Representation_Clause;
7021 procedure Check_Size
7025 Biased : out Boolean)
7027 UT : constant Entity_Id := Underlying_Type (T);
7033 -- Dismiss cases for generic types or types with previous errors
7036 or else UT = Any_Type
7037 or else Is_Generic_Type (UT)
7038 or else Is_Generic_Type (Root_Type (UT))
7042 -- Check case of bit packed array
7044 elsif Is_Array_Type (UT)
7045 and then Known_Static_Component_Size (UT)
7046 and then Is_Bit_Packed_Array (UT)
7054 Asiz := Component_Size (UT);
7055 Indx := First_Index (UT);
7057 Ityp := Etype (Indx);
7059 -- If non-static bound, then we are not in the business of
7060 -- trying to check the length, and indeed an error will be
7061 -- issued elsewhere, since sizes of non-static array types
7062 -- cannot be set implicitly or explicitly.
7064 if not Is_Static_Subtype (Ityp) then
7068 -- Otherwise accumulate next dimension
7070 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
7071 Expr_Value (Type_Low_Bound (Ityp)) +
7075 exit when No (Indx);
7081 Error_Msg_Uint_1 := Asiz;
7083 ("size for& too small, minimum allowed is ^", N, T);
7084 Set_Esize (T, Asiz);
7085 Set_RM_Size (T, Asiz);
7089 -- All other composite types are ignored
7091 elsif Is_Composite_Type (UT) then
7094 -- For fixed-point types, don't check minimum if type is not frozen,
7095 -- since we don't know all the characteristics of the type that can
7096 -- affect the size (e.g. a specified small) till freeze time.
7098 elsif Is_Fixed_Point_Type (UT)
7099 and then not Is_Frozen (UT)
7103 -- Cases for which a minimum check is required
7106 -- Ignore if specified size is correct for the type
7108 if Known_Esize (UT) and then Siz = Esize (UT) then
7112 -- Otherwise get minimum size
7114 M := UI_From_Int (Minimum_Size (UT));
7118 -- Size is less than minimum size, but one possibility remains
7119 -- that we can manage with the new size if we bias the type.
7121 M := UI_From_Int (Minimum_Size (UT, Biased => True));
7124 Error_Msg_Uint_1 := M;
7126 ("size for& too small, minimum allowed is ^", N, T);
7136 -------------------------
7137 -- Get_Alignment_Value --
7138 -------------------------
7140 function Get_Alignment_Value (Expr : Node_Id) return Uint is
7141 Align : constant Uint := Static_Integer (Expr);
7144 if Align = No_Uint then
7147 elsif Align <= 0 then
7148 Error_Msg_N ("alignment value must be positive", Expr);
7152 for J in Int range 0 .. 64 loop
7154 M : constant Uint := Uint_2 ** J;
7157 exit when M = Align;
7161 ("alignment value must be power of 2", Expr);
7169 end Get_Alignment_Value;
7175 procedure Initialize is
7177 Address_Clause_Checks.Init;
7178 Independence_Checks.Init;
7179 Unchecked_Conversions.Init;
7182 -------------------------
7183 -- Is_Operational_Item --
7184 -------------------------
7186 function Is_Operational_Item (N : Node_Id) return Boolean is
7188 if Nkind (N) /= N_Attribute_Definition_Clause then
7192 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
7194 return Id = Attribute_Input
7195 or else Id = Attribute_Output
7196 or else Id = Attribute_Read
7197 or else Id = Attribute_Write
7198 or else Id = Attribute_External_Tag;
7201 end Is_Operational_Item;
7207 function Minimum_Size
7209 Biased : Boolean := False) return Nat
7211 Lo : Uint := No_Uint;
7212 Hi : Uint := No_Uint;
7213 LoR : Ureal := No_Ureal;
7214 HiR : Ureal := No_Ureal;
7215 LoSet : Boolean := False;
7216 HiSet : Boolean := False;
7220 R_Typ : constant Entity_Id := Root_Type (T);
7223 -- If bad type, return 0
7225 if T = Any_Type then
7228 -- For generic types, just return zero. There cannot be any legitimate
7229 -- need to know such a size, but this routine may be called with a
7230 -- generic type as part of normal processing.
7232 elsif Is_Generic_Type (R_Typ)
7233 or else R_Typ = Any_Type
7237 -- Access types. Normally an access type cannot have a size smaller
7238 -- than the size of System.Address. The exception is on VMS, where
7239 -- we have short and long addresses, and it is possible for an access
7240 -- type to have a short address size (and thus be less than the size
7241 -- of System.Address itself). We simply skip the check for VMS, and
7242 -- leave it to the back end to do the check.
7244 elsif Is_Access_Type (T) then
7245 if OpenVMS_On_Target then
7248 return System_Address_Size;
7251 -- Floating-point types
7253 elsif Is_Floating_Point_Type (T) then
7254 return UI_To_Int (Esize (R_Typ));
7258 elsif Is_Discrete_Type (T) then
7260 -- The following loop is looking for the nearest compile time known
7261 -- bounds following the ancestor subtype chain. The idea is to find
7262 -- the most restrictive known bounds information.
7266 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7271 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
7272 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
7279 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
7280 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
7286 Ancest := Ancestor_Subtype (Ancest);
7289 Ancest := Base_Type (T);
7291 if Is_Generic_Type (Ancest) then
7297 -- Fixed-point types. We can't simply use Expr_Value to get the
7298 -- Corresponding_Integer_Value values of the bounds, since these do not
7299 -- get set till the type is frozen, and this routine can be called
7300 -- before the type is frozen. Similarly the test for bounds being static
7301 -- needs to include the case where we have unanalyzed real literals for
7304 elsif Is_Fixed_Point_Type (T) then
7306 -- The following loop is looking for the nearest compile time known
7307 -- bounds following the ancestor subtype chain. The idea is to find
7308 -- the most restrictive known bounds information.
7312 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7316 -- Note: In the following two tests for LoSet and HiSet, it may
7317 -- seem redundant to test for N_Real_Literal here since normally
7318 -- one would assume that the test for the value being known at
7319 -- compile time includes this case. However, there is a glitch.
7320 -- If the real literal comes from folding a non-static expression,
7321 -- then we don't consider any non- static expression to be known
7322 -- at compile time if we are in configurable run time mode (needed
7323 -- in some cases to give a clearer definition of what is and what
7324 -- is not accepted). So the test is indeed needed. Without it, we
7325 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
7328 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
7329 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
7331 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
7338 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
7339 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
7341 HiR := Expr_Value_R (Type_High_Bound (Ancest));
7347 Ancest := Ancestor_Subtype (Ancest);
7350 Ancest := Base_Type (T);
7352 if Is_Generic_Type (Ancest) then
7358 Lo := UR_To_Uint (LoR / Small_Value (T));
7359 Hi := UR_To_Uint (HiR / Small_Value (T));
7361 -- No other types allowed
7364 raise Program_Error;
7367 -- Fall through with Hi and Lo set. Deal with biased case
7370 and then not Is_Fixed_Point_Type (T)
7371 and then not (Is_Enumeration_Type (T)
7372 and then Has_Non_Standard_Rep (T)))
7373 or else Has_Biased_Representation (T)
7379 -- Signed case. Note that we consider types like range 1 .. -1 to be
7380 -- signed for the purpose of computing the size, since the bounds have
7381 -- to be accommodated in the base type.
7383 if Lo < 0 or else Hi < 0 then
7387 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
7388 -- Note that we accommodate the case where the bounds cross. This
7389 -- can happen either because of the way the bounds are declared
7390 -- or because of the algorithm in Freeze_Fixed_Point_Type.
7404 -- If both bounds are positive, make sure that both are represen-
7405 -- table in the case where the bounds are crossed. This can happen
7406 -- either because of the way the bounds are declared, or because of
7407 -- the algorithm in Freeze_Fixed_Point_Type.
7413 -- S = size, (can accommodate 0 .. (2**size - 1))
7416 while Hi >= Uint_2 ** S loop
7424 ---------------------------
7425 -- New_Stream_Subprogram --
7426 ---------------------------
7428 procedure New_Stream_Subprogram
7432 Nam : TSS_Name_Type)
7434 Loc : constant Source_Ptr := Sloc (N);
7435 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
7436 Subp_Id : Entity_Id;
7437 Subp_Decl : Node_Id;
7441 Defer_Declaration : constant Boolean :=
7442 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
7443 -- For a tagged type, there is a declaration for each stream attribute
7444 -- at the freeze point, and we must generate only a completion of this
7445 -- declaration. We do the same for private types, because the full view
7446 -- might be tagged. Otherwise we generate a declaration at the point of
7447 -- the attribute definition clause.
7449 function Build_Spec return Node_Id;
7450 -- Used for declaration and renaming declaration, so that this is
7451 -- treated as a renaming_as_body.
7457 function Build_Spec return Node_Id is
7458 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
7461 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
7464 Subp_Id := Make_Defining_Identifier (Loc, Sname);
7466 -- S : access Root_Stream_Type'Class
7468 Formals := New_List (
7469 Make_Parameter_Specification (Loc,
7470 Defining_Identifier =>
7471 Make_Defining_Identifier (Loc, Name_S),
7473 Make_Access_Definition (Loc,
7476 Designated_Type (Etype (F)), Loc))));
7478 if Nam = TSS_Stream_Input then
7479 Spec := Make_Function_Specification (Loc,
7480 Defining_Unit_Name => Subp_Id,
7481 Parameter_Specifications => Formals,
7482 Result_Definition => T_Ref);
7487 Make_Parameter_Specification (Loc,
7488 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
7489 Out_Present => Out_P,
7490 Parameter_Type => T_Ref));
7493 Make_Procedure_Specification (Loc,
7494 Defining_Unit_Name => Subp_Id,
7495 Parameter_Specifications => Formals);
7501 -- Start of processing for New_Stream_Subprogram
7504 F := First_Formal (Subp);
7506 if Ekind (Subp) = E_Procedure then
7507 Etyp := Etype (Next_Formal (F));
7509 Etyp := Etype (Subp);
7512 -- Prepare subprogram declaration and insert it as an action on the
7513 -- clause node. The visibility for this entity is used to test for
7514 -- visibility of the attribute definition clause (in the sense of
7515 -- 8.3(23) as amended by AI-195).
7517 if not Defer_Declaration then
7519 Make_Subprogram_Declaration (Loc,
7520 Specification => Build_Spec);
7522 -- For a tagged type, there is always a visible declaration for each
7523 -- stream TSS (it is a predefined primitive operation), and the
7524 -- completion of this declaration occurs at the freeze point, which is
7525 -- not always visible at places where the attribute definition clause is
7526 -- visible. So, we create a dummy entity here for the purpose of
7527 -- tracking the visibility of the attribute definition clause itself.
7531 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
7533 Make_Object_Declaration (Loc,
7534 Defining_Identifier => Subp_Id,
7535 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
7538 Insert_Action (N, Subp_Decl);
7539 Set_Entity (N, Subp_Id);
7542 Make_Subprogram_Renaming_Declaration (Loc,
7543 Specification => Build_Spec,
7544 Name => New_Reference_To (Subp, Loc));
7546 if Defer_Declaration then
7547 Set_TSS (Base_Type (Ent), Subp_Id);
7549 Insert_Action (N, Subp_Decl);
7550 Copy_TSS (Subp_Id, Base_Type (Ent));
7552 end New_Stream_Subprogram;
7554 ------------------------
7555 -- Rep_Item_Too_Early --
7556 ------------------------
7558 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
7560 -- Cannot apply non-operational rep items to generic types
7562 if Is_Operational_Item (N) then
7566 and then Is_Generic_Type (Root_Type (T))
7568 Error_Msg_N ("representation item not allowed for generic type", N);
7572 -- Otherwise check for incomplete type
7574 if Is_Incomplete_Or_Private_Type (T)
7575 and then No (Underlying_Type (T))
7577 (Nkind (N) /= N_Pragma
7578 or else Get_Pragma_Id (N) /= Pragma_Import)
7581 ("representation item must be after full type declaration", N);
7584 -- If the type has incomplete components, a representation clause is
7585 -- illegal but stream attributes and Convention pragmas are correct.
7587 elsif Has_Private_Component (T) then
7588 if Nkind (N) = N_Pragma then
7592 ("representation item must appear after type is fully defined",
7599 end Rep_Item_Too_Early;
7601 -----------------------
7602 -- Rep_Item_Too_Late --
7603 -----------------------
7605 function Rep_Item_Too_Late
7608 FOnly : Boolean := False) return Boolean
7611 Parent_Type : Entity_Id;
7614 -- Output the too late message. Note that this is not considered a
7615 -- serious error, since the effect is simply that we ignore the
7616 -- representation clause in this case.
7622 procedure Too_Late is
7624 Error_Msg_N ("|representation item appears too late!", N);
7627 -- Start of processing for Rep_Item_Too_Late
7630 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7631 -- types, which may be frozen if they appear in a representation clause
7632 -- for a local type.
7635 and then not From_With_Type (T)
7638 S := First_Subtype (T);
7640 if Present (Freeze_Node (S)) then
7642 ("?no more representation items for }", Freeze_Node (S), S);
7647 -- Check for case of non-tagged derived type whose parent either has
7648 -- primitive operations, or is a by reference type (RM 13.1(10)).
7652 and then Is_Derived_Type (T)
7653 and then not Is_Tagged_Type (T)
7655 Parent_Type := Etype (Base_Type (T));
7657 if Has_Primitive_Operations (Parent_Type) then
7660 ("primitive operations already defined for&!", N, Parent_Type);
7663 elsif Is_By_Reference_Type (Parent_Type) then
7666 ("parent type & is a by reference type!", N, Parent_Type);
7671 -- No error, link item into head of chain of rep items for the entity,
7672 -- but avoid chaining if we have an overloadable entity, and the pragma
7673 -- is one that can apply to multiple overloaded entities.
7675 if Is_Overloadable (T)
7676 and then Nkind (N) = N_Pragma
7679 Pname : constant Name_Id := Pragma_Name (N);
7681 if Pname = Name_Convention or else
7682 Pname = Name_Import or else
7683 Pname = Name_Export or else
7684 Pname = Name_External or else
7685 Pname = Name_Interface
7692 Record_Rep_Item (T, N);
7694 end Rep_Item_Too_Late;
7696 -------------------------------------
7697 -- Replace_Type_References_Generic --
7698 -------------------------------------
7700 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7702 function Replace_Node (N : Node_Id) return Traverse_Result;
7703 -- Processes a single node in the traversal procedure below, checking
7704 -- if node N should be replaced, and if so, doing the replacement.
7706 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7707 -- This instantiation provides the body of Replace_Type_References
7713 function Replace_Node (N : Node_Id) return Traverse_Result is
7718 -- Case of identifier
7720 if Nkind (N) = N_Identifier then
7722 -- If not the type name, all done with this node
7724 if Chars (N) /= TName then
7727 -- Otherwise do the replacement and we are done with this node
7730 Replace_Type_Reference (N);
7734 -- Case of selected component (which is what a qualification
7735 -- looks like in the unanalyzed tree, which is what we have.
7737 elsif Nkind (N) = N_Selected_Component then
7739 -- If selector name is not our type, keeping going (we might
7740 -- still have an occurrence of the type in the prefix).
7742 if Nkind (Selector_Name (N)) /= N_Identifier
7743 or else Chars (Selector_Name (N)) /= TName
7747 -- Selector name is our type, check qualification
7750 -- Loop through scopes and prefixes, doing comparison
7755 -- Continue if no more scopes or scope with no name
7757 if No (S) or else Nkind (S) not in N_Has_Chars then
7761 -- Do replace if prefix is an identifier matching the
7762 -- scope that we are currently looking at.
7764 if Nkind (P) = N_Identifier
7765 and then Chars (P) = Chars (S)
7767 Replace_Type_Reference (N);
7771 -- Go check scope above us if prefix is itself of the
7772 -- form of a selected component, whose selector matches
7773 -- the scope we are currently looking at.
7775 if Nkind (P) = N_Selected_Component
7776 and then Nkind (Selector_Name (P)) = N_Identifier
7777 and then Chars (Selector_Name (P)) = Chars (S)
7782 -- For anything else, we don't have a match, so keep on
7783 -- going, there are still some weird cases where we may
7784 -- still have a replacement within the prefix.
7792 -- Continue for any other node kind
7800 Replace_Type_Refs (N);
7801 end Replace_Type_References_Generic;
7803 -------------------------
7804 -- Same_Representation --
7805 -------------------------
7807 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7808 T1 : constant Entity_Id := Underlying_Type (Typ1);
7809 T2 : constant Entity_Id := Underlying_Type (Typ2);
7812 -- A quick check, if base types are the same, then we definitely have
7813 -- the same representation, because the subtype specific representation
7814 -- attributes (Size and Alignment) do not affect representation from
7815 -- the point of view of this test.
7817 if Base_Type (T1) = Base_Type (T2) then
7820 elsif Is_Private_Type (Base_Type (T2))
7821 and then Base_Type (T1) = Full_View (Base_Type (T2))
7826 -- Tagged types never have differing representations
7828 if Is_Tagged_Type (T1) then
7832 -- Representations are definitely different if conventions differ
7834 if Convention (T1) /= Convention (T2) then
7838 -- Representations are different if component alignments differ
7840 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7842 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7843 and then Component_Alignment (T1) /= Component_Alignment (T2)
7848 -- For arrays, the only real issue is component size. If we know the
7849 -- component size for both arrays, and it is the same, then that's
7850 -- good enough to know we don't have a change of representation.
7852 if Is_Array_Type (T1) then
7853 if Known_Component_Size (T1)
7854 and then Known_Component_Size (T2)
7855 and then Component_Size (T1) = Component_Size (T2)
7857 if VM_Target = No_VM then
7860 -- In VM targets the representation of arrays with aliased
7861 -- components differs from arrays with non-aliased components
7864 return Has_Aliased_Components (Base_Type (T1))
7866 Has_Aliased_Components (Base_Type (T2));
7871 -- Types definitely have same representation if neither has non-standard
7872 -- representation since default representations are always consistent.
7873 -- If only one has non-standard representation, and the other does not,
7874 -- then we consider that they do not have the same representation. They
7875 -- might, but there is no way of telling early enough.
7877 if Has_Non_Standard_Rep (T1) then
7878 if not Has_Non_Standard_Rep (T2) then
7882 return not Has_Non_Standard_Rep (T2);
7885 -- Here the two types both have non-standard representation, and we need
7886 -- to determine if they have the same non-standard representation.
7888 -- For arrays, we simply need to test if the component sizes are the
7889 -- same. Pragma Pack is reflected in modified component sizes, so this
7890 -- check also deals with pragma Pack.
7892 if Is_Array_Type (T1) then
7893 return Component_Size (T1) = Component_Size (T2);
7895 -- Tagged types always have the same representation, because it is not
7896 -- possible to specify different representations for common fields.
7898 elsif Is_Tagged_Type (T1) then
7901 -- Case of record types
7903 elsif Is_Record_Type (T1) then
7905 -- Packed status must conform
7907 if Is_Packed (T1) /= Is_Packed (T2) then
7910 -- Otherwise we must check components. Typ2 maybe a constrained
7911 -- subtype with fewer components, so we compare the components
7912 -- of the base types.
7915 Record_Case : declare
7916 CD1, CD2 : Entity_Id;
7918 function Same_Rep return Boolean;
7919 -- CD1 and CD2 are either components or discriminants. This
7920 -- function tests whether the two have the same representation
7926 function Same_Rep return Boolean is
7928 if No (Component_Clause (CD1)) then
7929 return No (Component_Clause (CD2));
7933 Present (Component_Clause (CD2))
7935 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7937 Esize (CD1) = Esize (CD2);
7941 -- Start of processing for Record_Case
7944 if Has_Discriminants (T1) then
7945 CD1 := First_Discriminant (T1);
7946 CD2 := First_Discriminant (T2);
7948 -- The number of discriminants may be different if the
7949 -- derived type has fewer (constrained by values). The
7950 -- invisible discriminants retain the representation of
7951 -- the original, so the discrepancy does not per se
7952 -- indicate a different representation.
7955 and then Present (CD2)
7957 if not Same_Rep then
7960 Next_Discriminant (CD1);
7961 Next_Discriminant (CD2);
7966 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
7967 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
7969 while Present (CD1) loop
7970 if not Same_Rep then
7973 Next_Component (CD1);
7974 Next_Component (CD2);
7982 -- For enumeration types, we must check each literal to see if the
7983 -- representation is the same. Note that we do not permit enumeration
7984 -- representation clauses for Character and Wide_Character, so these
7985 -- cases were already dealt with.
7987 elsif Is_Enumeration_Type (T1) then
7988 Enumeration_Case : declare
7992 L1 := First_Literal (T1);
7993 L2 := First_Literal (T2);
7995 while Present (L1) loop
7996 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
8006 end Enumeration_Case;
8008 -- Any other types have the same representation for these purposes
8013 end Same_Representation;
8019 procedure Set_Biased
8023 Biased : Boolean := True)
8027 Set_Has_Biased_Representation (E);
8029 if Warn_On_Biased_Representation then
8031 ("?" & Msg & " forces biased representation for&", N, E);
8036 --------------------
8037 -- Set_Enum_Esize --
8038 --------------------
8040 procedure Set_Enum_Esize (T : Entity_Id) is
8048 -- Find the minimum standard size (8,16,32,64) that fits
8050 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
8051 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
8054 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
8055 Sz := Standard_Character_Size; -- May be > 8 on some targets
8057 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
8060 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
8063 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
8068 if Hi < Uint_2**08 then
8069 Sz := Standard_Character_Size; -- May be > 8 on some targets
8071 elsif Hi < Uint_2**16 then
8074 elsif Hi < Uint_2**32 then
8077 else pragma Assert (Hi < Uint_2**63);
8082 -- That minimum is the proper size unless we have a foreign convention
8083 -- and the size required is 32 or less, in which case we bump the size
8084 -- up to 32. This is required for C and C++ and seems reasonable for
8085 -- all other foreign conventions.
8087 if Has_Foreign_Convention (T)
8088 and then Esize (T) < Standard_Integer_Size
8090 Init_Esize (T, Standard_Integer_Size);
8096 ------------------------------
8097 -- Validate_Address_Clauses --
8098 ------------------------------
8100 procedure Validate_Address_Clauses is
8102 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
8104 ACCR : Address_Clause_Check_Record
8105 renames Address_Clause_Checks.Table (J);
8116 -- Skip processing of this entry if warning already posted
8118 if not Address_Warning_Posted (ACCR.N) then
8120 Expr := Original_Node (Expression (ACCR.N));
8124 X_Alignment := Alignment (ACCR.X);
8125 Y_Alignment := Alignment (ACCR.Y);
8127 -- Similarly obtain sizes
8129 X_Size := Esize (ACCR.X);
8130 Y_Size := Esize (ACCR.Y);
8132 -- Check for large object overlaying smaller one
8135 and then X_Size > Uint_0
8136 and then X_Size > Y_Size
8139 ("?& overlays smaller object", ACCR.N, ACCR.X);
8141 ("\?program execution may be erroneous", ACCR.N);
8142 Error_Msg_Uint_1 := X_Size;
8144 ("\?size of & is ^", ACCR.N, ACCR.X);
8145 Error_Msg_Uint_1 := Y_Size;
8147 ("\?size of & is ^", ACCR.N, ACCR.Y);
8149 -- Check for inadequate alignment, both of the base object
8150 -- and of the offset, if any.
8152 -- Note: we do not check the alignment if we gave a size
8153 -- warning, since it would likely be redundant.
8155 elsif Y_Alignment /= Uint_0
8156 and then (Y_Alignment < X_Alignment
8159 Nkind (Expr) = N_Attribute_Reference
8161 Attribute_Name (Expr) = Name_Address
8163 Has_Compatible_Alignment
8164 (ACCR.X, Prefix (Expr))
8165 /= Known_Compatible))
8168 ("?specified address for& may be inconsistent "
8172 ("\?program execution may be erroneous (RM 13.3(27))",
8174 Error_Msg_Uint_1 := X_Alignment;
8176 ("\?alignment of & is ^",
8178 Error_Msg_Uint_1 := Y_Alignment;
8180 ("\?alignment of & is ^",
8182 if Y_Alignment >= X_Alignment then
8184 ("\?but offset is not multiple of alignment",
8191 end Validate_Address_Clauses;
8193 ---------------------------
8194 -- Validate_Independence --
8195 ---------------------------
8197 procedure Validate_Independence is
8198 SU : constant Uint := UI_From_Int (System_Storage_Unit);
8206 procedure Check_Array_Type (Atyp : Entity_Id);
8207 -- Checks if the array type Atyp has independent components, and
8208 -- if not, outputs an appropriate set of error messages.
8210 procedure No_Independence;
8211 -- Output message that independence cannot be guaranteed
8213 function OK_Component (C : Entity_Id) return Boolean;
8214 -- Checks one component to see if it is independently accessible, and
8215 -- if so yields True, otherwise yields False if independent access
8216 -- cannot be guaranteed. This is a conservative routine, it only
8217 -- returns True if it knows for sure, it returns False if it knows
8218 -- there is a problem, or it cannot be sure there is no problem.
8220 procedure Reason_Bad_Component (C : Entity_Id);
8221 -- Outputs continuation message if a reason can be determined for
8222 -- the component C being bad.
8224 ----------------------
8225 -- Check_Array_Type --
8226 ----------------------
8228 procedure Check_Array_Type (Atyp : Entity_Id) is
8229 Ctyp : constant Entity_Id := Component_Type (Atyp);
8232 -- OK if no alignment clause, no pack, and no component size
8234 if not Has_Component_Size_Clause (Atyp)
8235 and then not Has_Alignment_Clause (Atyp)
8236 and then not Is_Packed (Atyp)
8241 -- Check actual component size
8243 if not Known_Component_Size (Atyp)
8244 or else not (Addressable (Component_Size (Atyp))
8245 and then Component_Size (Atyp) < 64)
8246 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
8250 -- Bad component size, check reason
8252 if Has_Component_Size_Clause (Atyp) then
8254 Get_Attribute_Definition_Clause
8255 (Atyp, Attribute_Component_Size);
8258 Error_Msg_Sloc := Sloc (P);
8259 Error_Msg_N ("\because of Component_Size clause#", N);
8264 if Is_Packed (Atyp) then
8265 P := Get_Rep_Pragma (Atyp, Name_Pack);
8268 Error_Msg_Sloc := Sloc (P);
8269 Error_Msg_N ("\because of pragma Pack#", N);
8274 -- No reason found, just return
8279 -- Array type is OK independence-wise
8282 end Check_Array_Type;
8284 ---------------------
8285 -- No_Independence --
8286 ---------------------
8288 procedure No_Independence is
8290 if Pragma_Name (N) = Name_Independent then
8292 ("independence cannot be guaranteed for&", N, E);
8295 ("independent components cannot be guaranteed for&", N, E);
8297 end No_Independence;
8303 function OK_Component (C : Entity_Id) return Boolean is
8304 Rec : constant Entity_Id := Scope (C);
8305 Ctyp : constant Entity_Id := Etype (C);
8308 -- OK if no component clause, no Pack, and no alignment clause
8310 if No (Component_Clause (C))
8311 and then not Is_Packed (Rec)
8312 and then not Has_Alignment_Clause (Rec)
8317 -- Here we look at the actual component layout. A component is
8318 -- addressable if its size is a multiple of the Esize of the
8319 -- component type, and its starting position in the record has
8320 -- appropriate alignment, and the record itself has appropriate
8321 -- alignment to guarantee the component alignment.
8323 -- Make sure sizes are static, always assume the worst for any
8324 -- cases where we cannot check static values.
8326 if not (Known_Static_Esize (C)
8327 and then Known_Static_Esize (Ctyp))
8332 -- Size of component must be addressable or greater than 64 bits
8333 -- and a multiple of bytes.
8335 if not Addressable (Esize (C))
8336 and then Esize (C) < Uint_64
8341 -- Check size is proper multiple
8343 if Esize (C) mod Esize (Ctyp) /= 0 then
8347 -- Check alignment of component is OK
8349 if not Known_Component_Bit_Offset (C)
8350 or else Component_Bit_Offset (C) < Uint_0
8351 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
8356 -- Check alignment of record type is OK
8358 if not Known_Alignment (Rec)
8359 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8364 -- All tests passed, component is addressable
8369 --------------------------
8370 -- Reason_Bad_Component --
8371 --------------------------
8373 procedure Reason_Bad_Component (C : Entity_Id) is
8374 Rec : constant Entity_Id := Scope (C);
8375 Ctyp : constant Entity_Id := Etype (C);
8378 -- If component clause present assume that's the problem
8380 if Present (Component_Clause (C)) then
8381 Error_Msg_Sloc := Sloc (Component_Clause (C));
8382 Error_Msg_N ("\because of Component_Clause#", N);
8386 -- If pragma Pack clause present, assume that's the problem
8388 if Is_Packed (Rec) then
8389 P := Get_Rep_Pragma (Rec, Name_Pack);
8392 Error_Msg_Sloc := Sloc (P);
8393 Error_Msg_N ("\because of pragma Pack#", N);
8398 -- See if record has bad alignment clause
8400 if Has_Alignment_Clause (Rec)
8401 and then Known_Alignment (Rec)
8402 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8404 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
8407 Error_Msg_Sloc := Sloc (P);
8408 Error_Msg_N ("\because of Alignment clause#", N);
8412 -- Couldn't find a reason, so return without a message
8415 end Reason_Bad_Component;
8417 -- Start of processing for Validate_Independence
8420 for J in Independence_Checks.First .. Independence_Checks.Last loop
8421 N := Independence_Checks.Table (J).N;
8422 E := Independence_Checks.Table (J).E;
8423 IC := Pragma_Name (N) = Name_Independent_Components;
8425 -- Deal with component case
8427 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
8428 if not OK_Component (E) then
8430 Reason_Bad_Component (E);
8435 -- Deal with record with Independent_Components
8437 if IC and then Is_Record_Type (E) then
8438 Comp := First_Component_Or_Discriminant (E);
8439 while Present (Comp) loop
8440 if not OK_Component (Comp) then
8442 Reason_Bad_Component (Comp);
8446 Next_Component_Or_Discriminant (Comp);
8450 -- Deal with address clause case
8452 if Is_Object (E) then
8453 Addr := Address_Clause (E);
8455 if Present (Addr) then
8457 Error_Msg_Sloc := Sloc (Addr);
8458 Error_Msg_N ("\because of Address clause#", N);
8463 -- Deal with independent components for array type
8465 if IC and then Is_Array_Type (E) then
8466 Check_Array_Type (E);
8469 -- Deal with independent components for array object
8471 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
8472 Check_Array_Type (Etype (E));
8477 end Validate_Independence;
8479 -----------------------------------
8480 -- Validate_Unchecked_Conversion --
8481 -----------------------------------
8483 procedure Validate_Unchecked_Conversion
8485 Act_Unit : Entity_Id)
8492 -- Obtain source and target types. Note that we call Ancestor_Subtype
8493 -- here because the processing for generic instantiation always makes
8494 -- subtypes, and we want the original frozen actual types.
8496 -- If we are dealing with private types, then do the check on their
8497 -- fully declared counterparts if the full declarations have been
8498 -- encountered (they don't have to be visible, but they must exist!)
8500 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
8502 if Is_Private_Type (Source)
8503 and then Present (Underlying_Type (Source))
8505 Source := Underlying_Type (Source);
8508 Target := Ancestor_Subtype (Etype (Act_Unit));
8510 -- If either type is generic, the instantiation happens within a generic
8511 -- unit, and there is nothing to check. The proper check
8512 -- will happen when the enclosing generic is instantiated.
8514 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
8518 if Is_Private_Type (Target)
8519 and then Present (Underlying_Type (Target))
8521 Target := Underlying_Type (Target);
8524 -- Source may be unconstrained array, but not target
8526 if Is_Array_Type (Target)
8527 and then not Is_Constrained (Target)
8530 ("unchecked conversion to unconstrained array not allowed", N);
8534 -- Warn if conversion between two different convention pointers
8536 if Is_Access_Type (Target)
8537 and then Is_Access_Type (Source)
8538 and then Convention (Target) /= Convention (Source)
8539 and then Warn_On_Unchecked_Conversion
8541 -- Give warnings for subprogram pointers only on most targets. The
8542 -- exception is VMS, where data pointers can have different lengths
8543 -- depending on the pointer convention.
8545 if Is_Access_Subprogram_Type (Target)
8546 or else Is_Access_Subprogram_Type (Source)
8547 or else OpenVMS_On_Target
8550 ("?conversion between pointers with different conventions!", N);
8554 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
8555 -- warning when compiling GNAT-related sources.
8557 if Warn_On_Unchecked_Conversion
8558 and then not In_Predefined_Unit (N)
8559 and then RTU_Loaded (Ada_Calendar)
8561 (Chars (Source) = Name_Time
8563 Chars (Target) = Name_Time)
8565 -- If Ada.Calendar is loaded and the name of one of the operands is
8566 -- Time, there is a good chance that this is Ada.Calendar.Time.
8569 Calendar_Time : constant Entity_Id :=
8570 Full_View (RTE (RO_CA_Time));
8572 pragma Assert (Present (Calendar_Time));
8574 if Source = Calendar_Time
8575 or else Target = Calendar_Time
8578 ("?representation of 'Time values may change between " &
8579 "'G'N'A'T versions", N);
8584 -- Make entry in unchecked conversion table for later processing by
8585 -- Validate_Unchecked_Conversions, which will check sizes and alignments
8586 -- (using values set by the back-end where possible). This is only done
8587 -- if the appropriate warning is active.
8589 if Warn_On_Unchecked_Conversion then
8590 Unchecked_Conversions.Append
8591 (New_Val => UC_Entry'
8596 -- If both sizes are known statically now, then back end annotation
8597 -- is not required to do a proper check but if either size is not
8598 -- known statically, then we need the annotation.
8600 if Known_Static_RM_Size (Source)
8601 and then Known_Static_RM_Size (Target)
8605 Back_Annotate_Rep_Info := True;
8609 -- If unchecked conversion to access type, and access type is declared
8610 -- in the same unit as the unchecked conversion, then set the
8611 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
8614 if Is_Access_Type (Target) and then
8615 In_Same_Source_Unit (Target, N)
8617 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
8620 -- Generate N_Validate_Unchecked_Conversion node for back end in
8621 -- case the back end needs to perform special validation checks.
8623 -- Shouldn't this be in Exp_Ch13, since the check only gets done
8624 -- if we have full expansion and the back end is called ???
8627 Make_Validate_Unchecked_Conversion (Sloc (N));
8628 Set_Source_Type (Vnode, Source);
8629 Set_Target_Type (Vnode, Target);
8631 -- If the unchecked conversion node is in a list, just insert before it.
8632 -- If not we have some strange case, not worth bothering about.
8634 if Is_List_Member (N) then
8635 Insert_After (N, Vnode);
8637 end Validate_Unchecked_Conversion;
8639 ------------------------------------
8640 -- Validate_Unchecked_Conversions --
8641 ------------------------------------
8643 procedure Validate_Unchecked_Conversions is
8645 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8647 T : UC_Entry renames Unchecked_Conversions.Table (N);
8649 Eloc : constant Source_Ptr := T.Eloc;
8650 Source : constant Entity_Id := T.Source;
8651 Target : constant Entity_Id := T.Target;
8657 -- This validation check, which warns if we have unequal sizes for
8658 -- unchecked conversion, and thus potentially implementation
8659 -- dependent semantics, is one of the few occasions on which we
8660 -- use the official RM size instead of Esize. See description in
8661 -- Einfo "Handling of Type'Size Values" for details.
8663 if Serious_Errors_Detected = 0
8664 and then Known_Static_RM_Size (Source)
8665 and then Known_Static_RM_Size (Target)
8667 -- Don't do the check if warnings off for either type, note the
8668 -- deliberate use of OR here instead of OR ELSE to get the flag
8669 -- Warnings_Off_Used set for both types if appropriate.
8671 and then not (Has_Warnings_Off (Source)
8673 Has_Warnings_Off (Target))
8675 Source_Siz := RM_Size (Source);
8676 Target_Siz := RM_Size (Target);
8678 if Source_Siz /= Target_Siz then
8680 ("?types for unchecked conversion have different sizes!",
8683 if All_Errors_Mode then
8684 Error_Msg_Name_1 := Chars (Source);
8685 Error_Msg_Uint_1 := Source_Siz;
8686 Error_Msg_Name_2 := Chars (Target);
8687 Error_Msg_Uint_2 := Target_Siz;
8688 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8690 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8692 if Is_Discrete_Type (Source)
8693 and then Is_Discrete_Type (Target)
8695 if Source_Siz > Target_Siz then
8697 ("\?^ high order bits of source will be ignored!",
8700 elsif Is_Unsigned_Type (Source) then
8702 ("\?source will be extended with ^ high order " &
8703 "zero bits?!", Eloc);
8707 ("\?source will be extended with ^ high order " &
8712 elsif Source_Siz < Target_Siz then
8713 if Is_Discrete_Type (Target) then
8714 if Bytes_Big_Endian then
8716 ("\?target value will include ^ undefined " &
8721 ("\?target value will include ^ undefined " &
8728 ("\?^ trailing bits of target value will be " &
8729 "undefined!", Eloc);
8732 else pragma Assert (Source_Siz > Target_Siz);
8734 ("\?^ trailing bits of source will be ignored!",
8741 -- If both types are access types, we need to check the alignment.
8742 -- If the alignment of both is specified, we can do it here.
8744 if Serious_Errors_Detected = 0
8745 and then Ekind (Source) in Access_Kind
8746 and then Ekind (Target) in Access_Kind
8747 and then Target_Strict_Alignment
8748 and then Present (Designated_Type (Source))
8749 and then Present (Designated_Type (Target))
8752 D_Source : constant Entity_Id := Designated_Type (Source);
8753 D_Target : constant Entity_Id := Designated_Type (Target);
8756 if Known_Alignment (D_Source)
8757 and then Known_Alignment (D_Target)
8760 Source_Align : constant Uint := Alignment (D_Source);
8761 Target_Align : constant Uint := Alignment (D_Target);
8764 if Source_Align < Target_Align
8765 and then not Is_Tagged_Type (D_Source)
8767 -- Suppress warning if warnings suppressed on either
8768 -- type or either designated type. Note the use of
8769 -- OR here instead of OR ELSE. That is intentional,
8770 -- we would like to set flag Warnings_Off_Used in
8771 -- all types for which warnings are suppressed.
8773 and then not (Has_Warnings_Off (D_Source)
8775 Has_Warnings_Off (D_Target)
8777 Has_Warnings_Off (Source)
8779 Has_Warnings_Off (Target))
8781 Error_Msg_Uint_1 := Target_Align;
8782 Error_Msg_Uint_2 := Source_Align;
8783 Error_Msg_Node_1 := D_Target;
8784 Error_Msg_Node_2 := D_Source;
8786 ("?alignment of & (^) is stricter than " &
8787 "alignment of & (^)!", Eloc);
8789 ("\?resulting access value may have invalid " &
8790 "alignment!", Eloc);
8798 end Validate_Unchecked_Conversions;