1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Disp; use Exp_Disp;
33 with Exp_Tss; use Exp_Tss;
34 with Exp_Util; use Exp_Util;
36 with Lib.Xref; use Lib.Xref;
37 with Namet; use Namet;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
43 with Rtsfind; use Rtsfind;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Ch3; use Sem_Ch3;
47 with Sem_Ch6; use Sem_Ch6;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Eval; use Sem_Eval;
50 with Sem_Res; use Sem_Res;
51 with Sem_Type; use Sem_Type;
52 with Sem_Util; use Sem_Util;
53 with Sem_Warn; use Sem_Warn;
54 with Sinput; use Sinput;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Stringt; use Stringt;
59 with Targparm; use Targparm;
60 with Ttypes; use Ttypes;
61 with Tbuild; use Tbuild;
62 with Urealp; use Urealp;
63 with Warnsw; use Warnsw;
65 with GNAT.Heap_Sort_G;
67 package body Sem_Ch13 is
69 SSU : constant Pos := System_Storage_Unit;
70 -- Convenient short hand for commonly used constant
72 -----------------------
73 -- Local Subprograms --
74 -----------------------
76 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint);
77 -- This routine is called after setting one of the sizes of type entity
78 -- Typ to Size. The purpose is to deal with the situation of a derived
79 -- type whose inherited alignment is no longer appropriate for the new
80 -- size value. In this case, we reset the Alignment to unknown.
82 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id);
83 -- If Typ has predicates (indicated by Has_Predicates being set for Typ,
84 -- then either there are pragma Invariant entries on the rep chain for the
85 -- type (note that Predicate aspects are converted to pragma Predicate), or
86 -- there are inherited aspects from a parent type, or ancestor subtypes.
87 -- This procedure builds the spec and body for the Predicate function that
88 -- tests these predicates. N is the freeze node for the type. The spec of
89 -- the function is inserted before the freeze node, and the body of the
90 -- function is inserted after the freeze node.
92 procedure Build_Static_Predicate
96 -- Given a predicated type Typ, where Typ is a discrete static subtype,
97 -- whose predicate expression is Expr, tests if Expr is a static predicate,
98 -- and if so, builds the predicate range list. Nam is the name of the one
99 -- argument to the predicate function. Occurrences of the type name in the
100 -- predicate expression have been replaced by identifier references to this
101 -- name, which is unique, so any identifier with Chars matching Nam must be
102 -- a reference to the type. If the predicate is non-static, this procedure
103 -- returns doing nothing. If the predicate is static, then the predicate
104 -- list is stored in Static_Predicate (Typ), and the Expr is rewritten as
105 -- a canonicalized membership operation.
107 function Get_Alignment_Value (Expr : Node_Id) return Uint;
108 -- Given the expression for an alignment value, returns the corresponding
109 -- Uint value. If the value is inappropriate, then error messages are
110 -- posted as required, and a value of No_Uint is returned.
112 function Is_Operational_Item (N : Node_Id) return Boolean;
113 -- A specification for a stream attribute is allowed before the full type
114 -- is declared, as explained in AI-00137 and the corrigendum. Attributes
115 -- that do not specify a representation characteristic are operational
118 procedure New_Stream_Subprogram
122 Nam : TSS_Name_Type);
123 -- Create a subprogram renaming of a given stream attribute to the
124 -- designated subprogram and then in the tagged case, provide this as a
125 -- primitive operation, or in the non-tagged case make an appropriate TSS
126 -- entry. This is more properly an expansion activity than just semantics,
127 -- but the presence of user-defined stream functions for limited types is a
128 -- legality check, which is why this takes place here rather than in
129 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
130 -- function to be generated.
132 -- To avoid elaboration anomalies with freeze nodes, for untagged types
133 -- we generate both a subprogram declaration and a subprogram renaming
134 -- declaration, so that the attribute specification is handled as a
135 -- renaming_as_body. For tagged types, the specification is one of the
139 with procedure Replace_Type_Reference (N : Node_Id);
140 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id);
141 -- This is used to scan an expression for a predicate or invariant aspect
142 -- replacing occurrences of the name TName (the name of the subtype to
143 -- which the aspect applies) with appropriate references to the parameter
144 -- of the predicate function or invariant procedure. The procedure passed
145 -- as a generic parameter does the actual replacement of node N, which is
146 -- either a simple direct reference to TName, or a selected component that
147 -- represents an appropriately qualified occurrence of TName.
153 Biased : Boolean := True);
154 -- If Biased is True, sets Has_Biased_Representation flag for E, and
155 -- outputs a warning message at node N if Warn_On_Biased_Representation is
156 -- is True. This warning inserts the string Msg to describe the construct
159 ----------------------------------------------
160 -- Table for Validate_Unchecked_Conversions --
161 ----------------------------------------------
163 -- The following table collects unchecked conversions for validation.
164 -- Entries are made by Validate_Unchecked_Conversion and then the
165 -- call to Validate_Unchecked_Conversions does the actual error
166 -- checking and posting of warnings. The reason for this delayed
167 -- processing is to take advantage of back-annotations of size and
168 -- alignment values performed by the back end.
170 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
171 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
172 -- will already have modified all Sloc values if the -gnatD option is set.
174 type UC_Entry is record
175 Eloc : Source_Ptr; -- node used for posting warnings
176 Source : Entity_Id; -- source type for unchecked conversion
177 Target : Entity_Id; -- target type for unchecked conversion
180 package Unchecked_Conversions is new Table.Table (
181 Table_Component_Type => UC_Entry,
182 Table_Index_Type => Int,
183 Table_Low_Bound => 1,
185 Table_Increment => 200,
186 Table_Name => "Unchecked_Conversions");
188 ----------------------------------------
189 -- Table for Validate_Address_Clauses --
190 ----------------------------------------
192 -- If an address clause has the form
194 -- for X'Address use Expr
196 -- where Expr is of the form Y'Address or recursively is a reference
197 -- to a constant of either of these forms, and X and Y are entities of
198 -- objects, then if Y has a smaller alignment than X, that merits a
199 -- warning about possible bad alignment. The following table collects
200 -- address clauses of this kind. We put these in a table so that they
201 -- can be checked after the back end has completed annotation of the
202 -- alignments of objects, since we can catch more cases that way.
204 type Address_Clause_Check_Record is record
206 -- The address clause
209 -- The entity of the object overlaying Y
212 -- The entity of the object being overlaid
215 -- Whether the address is offset within Y
218 package Address_Clause_Checks is new Table.Table (
219 Table_Component_Type => Address_Clause_Check_Record,
220 Table_Index_Type => Int,
221 Table_Low_Bound => 1,
223 Table_Increment => 200,
224 Table_Name => "Address_Clause_Checks");
226 -----------------------------------------
227 -- Adjust_Record_For_Reverse_Bit_Order --
228 -----------------------------------------
230 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
235 -- Processing depends on version of Ada
237 -- For Ada 95, we just renumber bits within a storage unit. We do the
238 -- same for Ada 83 mode, since we recognize the Bit_Order attribute in
239 -- Ada 83, and are free to add this extension.
241 if Ada_Version < Ada_2005 then
242 Comp := First_Component_Or_Discriminant (R);
243 while Present (Comp) loop
244 CC := Component_Clause (Comp);
246 -- If component clause is present, then deal with the non-default
247 -- bit order case for Ada 95 mode.
249 -- We only do this processing for the base type, and in fact that
250 -- is important, since otherwise if there are record subtypes, we
251 -- could reverse the bits once for each subtype, which is wrong.
254 and then Ekind (R) = E_Record_Type
257 CFB : constant Uint := Component_Bit_Offset (Comp);
258 CSZ : constant Uint := Esize (Comp);
259 CLC : constant Node_Id := Component_Clause (Comp);
260 Pos : constant Node_Id := Position (CLC);
261 FB : constant Node_Id := First_Bit (CLC);
263 Storage_Unit_Offset : constant Uint :=
264 CFB / System_Storage_Unit;
266 Start_Bit : constant Uint :=
267 CFB mod System_Storage_Unit;
270 -- Cases where field goes over storage unit boundary
272 if Start_Bit + CSZ > System_Storage_Unit then
274 -- Allow multi-byte field but generate warning
276 if Start_Bit mod System_Storage_Unit = 0
277 and then CSZ mod System_Storage_Unit = 0
280 ("multi-byte field specified with non-standard"
281 & " Bit_Order?", CLC);
283 if Bytes_Big_Endian then
285 ("bytes are not reversed "
286 & "(component is big-endian)?", CLC);
289 ("bytes are not reversed "
290 & "(component is little-endian)?", CLC);
293 -- Do not allow non-contiguous field
297 ("attempt to specify non-contiguous field "
298 & "not permitted", CLC);
300 ("\caused by non-standard Bit_Order "
303 ("\consider possibility of using "
304 & "Ada 2005 mode here", CLC);
307 -- Case where field fits in one storage unit
310 -- Give warning if suspicious component clause
312 if Intval (FB) >= System_Storage_Unit
313 and then Warn_On_Reverse_Bit_Order
316 ("?Bit_Order clause does not affect " &
317 "byte ordering", Pos);
319 Intval (Pos) + Intval (FB) /
322 ("?position normalized to ^ before bit " &
323 "order interpreted", Pos);
326 -- Here is where we fix up the Component_Bit_Offset value
327 -- to account for the reverse bit order. Some examples of
328 -- what needs to be done are:
330 -- First_Bit .. Last_Bit Component_Bit_Offset
342 -- The rule is that the first bit is is obtained by
343 -- subtracting the old ending bit from storage_unit - 1.
345 Set_Component_Bit_Offset
347 (Storage_Unit_Offset * System_Storage_Unit) +
348 (System_Storage_Unit - 1) -
349 (Start_Bit + CSZ - 1));
351 Set_Normalized_First_Bit
353 Component_Bit_Offset (Comp) mod
354 System_Storage_Unit);
359 Next_Component_Or_Discriminant (Comp);
362 -- For Ada 2005, we do machine scalar processing, as fully described In
363 -- AI-133. This involves gathering all components which start at the
364 -- same byte offset and processing them together. Same approach is still
365 -- valid in later versions including Ada 2012.
369 Max_Machine_Scalar_Size : constant Uint :=
371 (Standard_Long_Long_Integer_Size);
372 -- We use this as the maximum machine scalar size
375 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
378 -- This first loop through components does two things. First it
379 -- deals with the case of components with component clauses whose
380 -- length is greater than the maximum machine scalar size (either
381 -- accepting them or rejecting as needed). Second, it counts the
382 -- number of components with component clauses whose length does
383 -- not exceed this maximum for later processing.
386 Comp := First_Component_Or_Discriminant (R);
387 while Present (Comp) loop
388 CC := Component_Clause (Comp);
392 Fbit : constant Uint :=
393 Static_Integer (First_Bit (CC));
394 Lbit : constant Uint :=
395 Static_Integer (Last_Bit (CC));
398 -- Case of component with last bit >= max machine scalar
400 if Lbit >= Max_Machine_Scalar_Size then
402 -- This is allowed only if first bit is zero, and
403 -- last bit + 1 is a multiple of storage unit size.
405 if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
407 -- This is the case to give a warning if enabled
409 if Warn_On_Reverse_Bit_Order then
411 ("multi-byte field specified with "
412 & " non-standard Bit_Order?", CC);
414 if Bytes_Big_Endian then
416 ("\bytes are not reversed "
417 & "(component is big-endian)?", CC);
420 ("\bytes are not reversed "
421 & "(component is little-endian)?", CC);
425 -- Give error message for RM 13.4.1(10) violation
429 ("machine scalar rules not followed for&",
430 First_Bit (CC), Comp);
432 Error_Msg_Uint_1 := Lbit;
433 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
435 ("\last bit (^) exceeds maximum machine "
439 if (Lbit + 1) mod SSU /= 0 then
440 Error_Msg_Uint_1 := SSU;
442 ("\and is not a multiple of Storage_Unit (^) "
447 Error_Msg_Uint_1 := Fbit;
449 ("\and first bit (^) is non-zero "
455 -- OK case of machine scalar related component clause,
456 -- For now, just count them.
459 Num_CC := Num_CC + 1;
464 Next_Component_Or_Discriminant (Comp);
467 -- We need to sort the component clauses on the basis of the
468 -- Position values in the clause, so we can group clauses with
469 -- the same Position. together to determine the relevant machine
473 Comps : array (0 .. Num_CC) of Entity_Id;
474 -- Array to collect component and discriminant entities. The
475 -- data starts at index 1, the 0'th entry is for the sort
478 function CP_Lt (Op1, Op2 : Natural) return Boolean;
479 -- Compare routine for Sort
481 procedure CP_Move (From : Natural; To : Natural);
482 -- Move routine for Sort
484 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
488 -- Start and stop positions in the component list of the set of
489 -- components with the same starting position (that constitute
490 -- components in a single machine scalar).
493 -- Maximum last bit value of any component in this set
496 -- Corresponding machine scalar size
502 function CP_Lt (Op1, Op2 : Natural) return Boolean is
504 return Position (Component_Clause (Comps (Op1))) <
505 Position (Component_Clause (Comps (Op2)));
512 procedure CP_Move (From : Natural; To : Natural) is
514 Comps (To) := Comps (From);
517 -- Start of processing for Sort_CC
520 -- Collect the machine scalar relevant component clauses
523 Comp := First_Component_Or_Discriminant (R);
524 while Present (Comp) loop
526 CC : constant Node_Id := Component_Clause (Comp);
529 -- Collect only component clauses whose last bit is less
530 -- than machine scalar size. Any component clause whose
531 -- last bit exceeds this value does not take part in
532 -- machine scalar layout considerations. The test for
533 -- Error_Posted makes sure we exclude component clauses
534 -- for which we already posted an error.
537 and then not Error_Posted (Last_Bit (CC))
538 and then Static_Integer (Last_Bit (CC)) <
539 Max_Machine_Scalar_Size
541 Num_CC := Num_CC + 1;
542 Comps (Num_CC) := Comp;
546 Next_Component_Or_Discriminant (Comp);
549 -- Sort by ascending position number
551 Sorting.Sort (Num_CC);
553 -- We now have all the components whose size does not exceed
554 -- the max machine scalar value, sorted by starting position.
555 -- In this loop we gather groups of clauses starting at the
556 -- same position, to process them in accordance with AI-133.
559 while Stop < Num_CC loop
564 (Last_Bit (Component_Clause (Comps (Start))));
565 while Stop < Num_CC loop
567 (Position (Component_Clause (Comps (Stop + 1)))) =
569 (Position (Component_Clause (Comps (Stop))))
577 (Component_Clause (Comps (Stop)))));
583 -- Now we have a group of component clauses from Start to
584 -- Stop whose positions are identical, and MaxL is the
585 -- maximum last bit value of any of these components.
587 -- We need to determine the corresponding machine scalar
588 -- size. This loop assumes that machine scalar sizes are
589 -- even, and that each possible machine scalar has twice
590 -- as many bits as the next smaller one.
592 MSS := Max_Machine_Scalar_Size;
594 and then (MSS / 2) >= SSU
595 and then (MSS / 2) > MaxL
600 -- Here is where we fix up the Component_Bit_Offset value
601 -- to account for the reverse bit order. Some examples of
602 -- what needs to be done for the case of a machine scalar
605 -- First_Bit .. Last_Bit Component_Bit_Offset
617 -- The rule is that the first bit is obtained by subtracting
618 -- the old ending bit from machine scalar size - 1.
620 for C in Start .. Stop loop
622 Comp : constant Entity_Id := Comps (C);
623 CC : constant Node_Id :=
624 Component_Clause (Comp);
625 LB : constant Uint :=
626 Static_Integer (Last_Bit (CC));
627 NFB : constant Uint := MSS - Uint_1 - LB;
628 NLB : constant Uint := NFB + Esize (Comp) - 1;
629 Pos : constant Uint :=
630 Static_Integer (Position (CC));
633 if Warn_On_Reverse_Bit_Order then
634 Error_Msg_Uint_1 := MSS;
636 ("info: reverse bit order in machine " &
637 "scalar of length^?", First_Bit (CC));
638 Error_Msg_Uint_1 := NFB;
639 Error_Msg_Uint_2 := NLB;
641 if Bytes_Big_Endian then
643 ("?\info: big-endian range for "
644 & "component & is ^ .. ^",
645 First_Bit (CC), Comp);
648 ("?\info: little-endian range "
649 & "for component & is ^ .. ^",
650 First_Bit (CC), Comp);
654 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
655 Set_Normalized_First_Bit (Comp, NFB mod SSU);
662 end Adjust_Record_For_Reverse_Bit_Order;
664 -------------------------------------
665 -- Alignment_Check_For_Size_Change --
666 -------------------------------------
668 procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint) is
670 -- If the alignment is known, and not set by a rep clause, and is
671 -- inconsistent with the size being set, then reset it to unknown,
672 -- we assume in this case that the size overrides the inherited
673 -- alignment, and that the alignment must be recomputed.
675 if Known_Alignment (Typ)
676 and then not Has_Alignment_Clause (Typ)
677 and then Size mod (Alignment (Typ) * SSU) /= 0
679 Init_Alignment (Typ);
681 end Alignment_Check_For_Size_Change;
683 -----------------------------------
684 -- Analyze_Aspect_Specifications --
685 -----------------------------------
687 procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is
692 L : constant List_Id := Aspect_Specifications (N);
694 Ins_Node : Node_Id := N;
695 -- Insert pragmas (except Pre/Post/Invariant/Predicate) after this node
697 -- The general processing involves building an attribute definition
698 -- clause or a pragma node that corresponds to the aspect. Then one
699 -- of two things happens:
701 -- If we are required to delay the evaluation of this aspect to the
702 -- freeze point, we attach the corresponding pragma/attribute definition
703 -- clause to the aspect specification node, which is then placed in the
704 -- Rep Item chain. In this case we mark the entity by setting the flag
705 -- Has_Delayed_Aspects and we evaluate the rep item at the freeze point.
707 -- If no delay is required, we just insert the pragma or attribute
708 -- after the declaration, and it will get processed by the normal
709 -- circuit. The From_Aspect_Specification flag is set on the pragma
710 -- or attribute definition node in either case to activate special
711 -- processing (e.g. not traversing the list of homonyms for inline).
713 Delay_Required : Boolean := False;
714 -- Set True if delay is required
717 pragma Assert (Present (L));
719 -- Loop through aspects
722 Aspect_Loop : while Present (Aspect) loop
724 Loc : constant Source_Ptr := Sloc (Aspect);
725 Id : constant Node_Id := Identifier (Aspect);
726 Expr : constant Node_Id := Expression (Aspect);
727 Nam : constant Name_Id := Chars (Id);
728 A_Id : constant Aspect_Id := Get_Aspect_Id (Nam);
731 Eloc : Source_Ptr := Sloc (Expr);
732 -- Source location of expression, modified when we split PPC's
734 procedure Check_False_Aspect_For_Derived_Type;
735 -- This procedure checks for the case of a false aspect for a
736 -- derived type, which improperly tries to cancel an aspect
737 -- inherited from the parent;
739 -----------------------------------------
740 -- Check_False_Aspect_For_Derived_Type --
741 -----------------------------------------
743 procedure Check_False_Aspect_For_Derived_Type is
745 -- We are only checking derived types
747 if not Is_Derived_Type (E) then
752 when Aspect_Atomic | Aspect_Shared =>
753 if not Is_Atomic (E) then
757 when Aspect_Atomic_Components =>
758 if not Has_Atomic_Components (E) then
762 when Aspect_Discard_Names =>
763 if not Discard_Names (E) then
768 if not Is_Packed (E) then
772 when Aspect_Unchecked_Union =>
773 if not Is_Unchecked_Union (E) then
777 when Aspect_Volatile =>
778 if not Is_Volatile (E) then
782 when Aspect_Volatile_Components =>
783 if not Has_Volatile_Components (E) then
791 -- Fall through means we are canceling an inherited aspect
793 Error_Msg_Name_1 := Nam;
795 ("derived type& inherits aspect%, cannot cancel", Expr, E);
796 end Check_False_Aspect_For_Derived_Type;
798 -- Start of processing for Aspect_Loop
801 -- Skip aspect if already analyzed (not clear if this is needed)
803 if Analyzed (Aspect) then
807 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 pragma Assert (not Delay_Required);
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 pragma Assert (not Delay_Required);
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 pragma Assert (not Delay_Required);
1052 Delay_Required := True;
1053 Set_Is_Delayed_Aspect (Aspect);
1056 -- Aspects corresponding to pragmas with two arguments, where
1057 -- the first argument is a local name referring to the entity,
1058 -- and the second argument is the aspect definition expression
1059 -- which is an expression that does not get analyzed.
1061 when Aspect_Suppress |
1062 Aspect_Unsuppress =>
1064 -- Construct the pragma
1068 Pragma_Argument_Associations => New_List (
1069 New_Occurrence_Of (E, Loc),
1070 Relocate_Node (Expr)),
1071 Pragma_Identifier =>
1072 Make_Identifier (Sloc (Id), Chars (Id)));
1074 -- We don't have to play the delay game here, since the only
1075 -- values are check names which don't get analyzed anyway.
1077 pragma Assert (not Delay_Required);
1079 -- Aspects corresponding to pragmas with two arguments, where
1080 -- the second argument is a local name referring to the entity,
1081 -- and the first argument is the aspect definition expression.
1083 when Aspect_Warnings =>
1085 -- Construct the pragma
1089 Pragma_Argument_Associations => New_List (
1090 Relocate_Node (Expr),
1091 New_Occurrence_Of (E, Loc)),
1092 Pragma_Identifier =>
1093 Make_Identifier (Sloc (Id), Chars (Id)),
1094 Class_Present => Class_Present (Aspect));
1096 -- We don't have to play the delay game here, since the only
1097 -- values are ON/OFF which don't get analyzed anyway.
1099 pragma Assert (not Delay_Required);
1101 -- Default_Value and Default_Component_Value aspects. These
1102 -- are specially handled because they have no corresponding
1103 -- pragmas or attributes.
1105 when Aspect_Default_Value | Aspect_Default_Component_Value =>
1106 Error_Msg_Name_1 := Chars (Id);
1108 if not Is_Type (E) then
1109 Error_Msg_N ("aspect% can only apply to a type", Id);
1112 elsif not Is_First_Subtype (E) then
1113 Error_Msg_N ("aspect% cannot apply to subtype", Id);
1116 elsif A_Id = Aspect_Default_Value
1117 and then not Is_Scalar_Type (E)
1120 ("aspect% can only be applied to scalar type", Id);
1123 elsif A_Id = Aspect_Default_Component_Value then
1124 if not Is_Array_Type (E) then
1126 ("aspect% can only be applied to array type", Id);
1128 elsif not Is_Scalar_Type (Component_Type (E)) then
1130 ("aspect% requires scalar components", Id);
1136 Delay_Required := True;
1137 Set_Is_Delayed_Aspect (Aspect);
1138 Set_Has_Default_Aspect (Base_Type (Entity (Ent)));
1140 when Aspect_Attach_Handler =>
1143 Pragma_Identifier =>
1144 Make_Identifier (Sloc (Id), Name_Attach_Handler),
1145 Pragma_Argument_Associations =>
1146 New_List (Ent, Relocate_Node (Expr)));
1148 Set_From_Aspect_Specification (Aitem, True);
1150 pragma Assert (not Delay_Required);
1152 when Aspect_Priority |
1153 Aspect_Interrupt_Priority |
1154 Aspect_Dispatching_Domain |
1160 if A_Id = Aspect_Priority then
1161 Pname := Name_Priority;
1163 elsif A_Id = Aspect_Interrupt_Priority then
1164 Pname := Name_Interrupt_Priority;
1166 elsif A_Id = Aspect_CPU then
1170 Pname := Name_Dispatching_Domain;
1175 Pragma_Identifier =>
1176 Make_Identifier (Sloc (Id), Pname),
1177 Pragma_Argument_Associations =>
1179 (Make_Pragma_Argument_Association
1181 Expression => Relocate_Node (Expr))));
1183 Set_From_Aspect_Specification (Aitem, True);
1185 pragma Assert (not Delay_Required);
1188 -- Aspects Pre/Post generate Precondition/Postcondition pragmas
1189 -- with a first argument that is the expression, and a second
1190 -- argument that is an informative message if the test fails.
1191 -- This is inserted right after the declaration, to get the
1192 -- required pragma placement. The processing for the pragmas
1193 -- takes care of the required delay.
1195 when Pre_Post_Aspects => declare
1199 if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then
1200 Pname := Name_Precondition;
1202 Pname := Name_Postcondition;
1205 -- If the expressions is of the form A and then B, then
1206 -- we generate separate Pre/Post aspects for the separate
1207 -- clauses. Since we allow multiple pragmas, there is no
1208 -- problem in allowing multiple Pre/Post aspects internally.
1209 -- These should be treated in reverse order (B first and
1210 -- A second) since they are later inserted just after N in
1211 -- the order they are treated. This way, the pragma for A
1212 -- ends up preceding the pragma for B, which may have an
1213 -- importance for the error raised (either constraint error
1214 -- or precondition error).
1216 -- We do not do this for Pre'Class, since we have to put
1217 -- these conditions together in a complex OR expression
1219 if Pname = Name_Postcondition
1220 or else not Class_Present (Aspect)
1222 while Nkind (Expr) = N_And_Then loop
1223 Insert_After (Aspect,
1224 Make_Aspect_Specification (Sloc (Left_Opnd (Expr)),
1225 Identifier => Identifier (Aspect),
1226 Expression => Relocate_Node (Left_Opnd (Expr)),
1227 Class_Present => Class_Present (Aspect),
1228 Split_PPC => True));
1229 Rewrite (Expr, Relocate_Node (Right_Opnd (Expr)));
1230 Eloc := Sloc (Expr);
1234 -- Build the precondition/postcondition pragma
1238 Pragma_Identifier =>
1239 Make_Identifier (Sloc (Id), Pname),
1240 Class_Present => Class_Present (Aspect),
1241 Split_PPC => Split_PPC (Aspect),
1242 Pragma_Argument_Associations => New_List (
1243 Make_Pragma_Argument_Association (Eloc,
1244 Chars => Name_Check,
1245 Expression => Relocate_Node (Expr))));
1247 -- Add message unless exception messages are suppressed
1249 if not Opt.Exception_Locations_Suppressed then
1250 Append_To (Pragma_Argument_Associations (Aitem),
1251 Make_Pragma_Argument_Association (Eloc,
1252 Chars => Name_Message,
1254 Make_String_Literal (Eloc,
1256 & Get_Name_String (Pname)
1258 & Build_Location_String (Eloc))));
1261 Set_From_Aspect_Specification (Aitem, True);
1262 Set_Is_Delayed_Aspect (Aspect);
1264 -- For Pre/Post cases, insert immediately after the entity
1265 -- declaration, since that is the required pragma placement.
1266 -- Note that for these aspects, we do not have to worry
1267 -- about delay issues, since the pragmas themselves deal
1268 -- with delay of visibility for the expression analysis.
1270 -- If the entity is a library-level subprogram, the pre/
1271 -- postconditions must be treated as late pragmas.
1273 if Nkind (Parent (N)) = N_Compilation_Unit then
1274 Add_Global_Declaration (Aitem);
1276 Insert_After (N, Aitem);
1282 -- Invariant aspects generate a corresponding pragma with a
1283 -- first argument that is the entity, a second argument that is
1284 -- the expression and a third argument that is an appropriate
1285 -- message. This is inserted right after the declaration, to
1286 -- get the required pragma placement. The pragma processing
1287 -- takes care of the required delay.
1289 when Aspect_Invariant |
1290 Aspect_Type_Invariant =>
1292 -- Analysis of the pragma will verify placement legality:
1293 -- an invariant must apply to a private type, or appear in
1294 -- the private part of a spec and apply to a completion.
1296 -- Construct the pragma
1300 Pragma_Argument_Associations =>
1301 New_List (Ent, Relocate_Node (Expr)),
1302 Class_Present => Class_Present (Aspect),
1303 Pragma_Identifier =>
1304 Make_Identifier (Sloc (Id), Name_Invariant));
1306 -- Add message unless exception messages are suppressed
1308 if not Opt.Exception_Locations_Suppressed then
1309 Append_To (Pragma_Argument_Associations (Aitem),
1310 Make_Pragma_Argument_Association (Eloc,
1311 Chars => Name_Message,
1313 Make_String_Literal (Eloc,
1314 Strval => "failed invariant from "
1315 & Build_Location_String (Eloc))));
1318 Set_From_Aspect_Specification (Aitem, True);
1319 Set_Is_Delayed_Aspect (Aspect);
1321 -- For Invariant case, insert immediately after the entity
1322 -- declaration. We do not have to worry about delay issues
1323 -- since the pragma processing takes care of this.
1325 Insert_After (N, Aitem);
1328 -- Predicate aspects generate a corresponding pragma with a
1329 -- first argument that is the entity, and the second argument
1330 -- is the expression.
1332 when Aspect_Dynamic_Predicate |
1334 Aspect_Static_Predicate =>
1336 -- Construct the pragma (always a pragma Predicate, with
1337 -- flags recording whether it is static/dynamic).
1341 Pragma_Argument_Associations =>
1342 New_List (Ent, Relocate_Node (Expr)),
1343 Class_Present => Class_Present (Aspect),
1344 Pragma_Identifier =>
1345 Make_Identifier (Sloc (Id), Name_Predicate));
1347 Set_From_Aspect_Specification (Aitem, True);
1349 -- Set special flags for dynamic/static cases
1351 if A_Id = Aspect_Dynamic_Predicate then
1352 Set_From_Dynamic_Predicate (Aitem);
1353 elsif A_Id = Aspect_Static_Predicate then
1354 Set_From_Static_Predicate (Aitem);
1357 -- Make sure we have a freeze node (it might otherwise be
1358 -- missing in cases like subtype X is Y, and we would not
1359 -- have a place to build the predicate function).
1361 Set_Has_Predicates (E);
1363 if Is_Private_Type (E)
1364 and then Present (Full_View (E))
1366 Set_Has_Predicates (Full_View (E));
1367 Set_Has_Delayed_Aspects (Full_View (E));
1370 Ensure_Freeze_Node (E);
1371 Set_Is_Delayed_Aspect (Aspect);
1372 Delay_Required := True;
1374 when Aspect_Test_Case => declare
1376 Comp_Expr : Node_Id;
1377 Comp_Assn : Node_Id;
1382 if Nkind (Parent (N)) = N_Compilation_Unit then
1384 ("incorrect placement of aspect `Test_Case`", E);
1388 if Nkind (Expr) /= N_Aggregate then
1390 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1394 Comp_Expr := First (Expressions (Expr));
1395 while Present (Comp_Expr) loop
1396 Append (Relocate_Node (Comp_Expr), Args);
1400 Comp_Assn := First (Component_Associations (Expr));
1401 while Present (Comp_Assn) loop
1402 if List_Length (Choices (Comp_Assn)) /= 1
1404 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
1407 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1411 Append (Make_Pragma_Argument_Association (
1412 Sloc => Sloc (Comp_Assn),
1413 Chars => Chars (First (Choices (Comp_Assn))),
1414 Expression => Relocate_Node (Expression (Comp_Assn))),
1419 -- Build the test-case pragma
1423 Pragma_Identifier =>
1424 Make_Identifier (Sloc (Id), Name_Test_Case),
1425 Pragma_Argument_Associations =>
1428 Set_From_Aspect_Specification (Aitem, True);
1429 Set_Is_Delayed_Aspect (Aspect);
1431 -- Insert immediately after the entity declaration
1433 Insert_After (N, Aitem);
1439 -- If a delay is required, we delay the freeze (not much point in
1440 -- delaying the aspect if we don't delay the freeze!). The pragma
1441 -- or attribute clause if there is one is then attached to the
1442 -- aspect specification which is placed in the rep item list.
1444 if Delay_Required then
1445 if Present (Aitem) then
1446 Set_From_Aspect_Specification (Aitem, True);
1447 Set_Is_Delayed_Aspect (Aitem);
1448 Set_Aspect_Rep_Item (Aspect, Aitem);
1451 Ensure_Freeze_Node (E);
1452 Set_Has_Delayed_Aspects (E);
1453 Record_Rep_Item (E, Aspect);
1455 -- If no delay required, insert the pragma/clause in the tree
1458 Set_From_Aspect_Specification (Aitem, True);
1460 -- If this is a compilation unit, we will put the pragma in
1461 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1463 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1465 Aux : constant Node_Id :=
1466 Aux_Decls_Node (Parent (Ins_Node));
1469 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1471 if No (Pragmas_After (Aux)) then
1472 Set_Pragmas_After (Aux, Empty_List);
1475 -- For Pre_Post put at start of list, otherwise at end
1477 if A_Id in Pre_Post_Aspects then
1478 Prepend (Aitem, Pragmas_After (Aux));
1480 Append (Aitem, Pragmas_After (Aux));
1484 -- Here if not compilation unit case
1489 -- For Pre/Post cases, insert immediately after the
1490 -- entity declaration, since that is the required pragma
1493 when Pre_Post_Aspects =>
1494 Insert_After (N, Aitem);
1496 -- For Priority aspects, insert into the task or
1497 -- protected definition, which we need to create if it's
1498 -- not there. The same applies to CPU and
1499 -- Dispatching_Domain but only to tasks.
1501 when Aspect_Priority |
1502 Aspect_Interrupt_Priority |
1503 Aspect_Dispatching_Domain |
1506 T : Node_Id; -- the type declaration
1507 L : List_Id; -- list of decls of task/protected
1510 if Nkind (N) = N_Object_Declaration then
1511 T := Parent (Etype (Defining_Identifier (N)));
1516 if Nkind (T) = N_Protected_Type_Declaration
1517 and then A_Id /= Aspect_Dispatching_Domain
1518 and then A_Id /= Aspect_CPU
1521 (Present (Protected_Definition (T)));
1523 L := Visible_Declarations
1524 (Protected_Definition (T));
1526 elsif Nkind (T) = N_Task_Type_Declaration then
1527 if No (Task_Definition (T)) then
1530 Make_Task_Definition
1532 Visible_Declarations => New_List,
1533 End_Label => Empty));
1536 L := Visible_Declarations (Task_Definition (T));
1539 raise Program_Error;
1542 Prepend (Aitem, To => L);
1544 -- Analyze rewritten pragma. Otherwise, its
1545 -- analysis is done too late, after the task or
1546 -- protected object has been created.
1551 -- For all other cases, insert in sequence
1554 Insert_After (Ins_Node, Aitem);
1563 end loop Aspect_Loop;
1564 end Analyze_Aspect_Specifications;
1566 -----------------------
1567 -- Analyze_At_Clause --
1568 -----------------------
1570 -- An at clause is replaced by the corresponding Address attribute
1571 -- definition clause that is the preferred approach in Ada 95.
1573 procedure Analyze_At_Clause (N : Node_Id) is
1574 CS : constant Boolean := Comes_From_Source (N);
1577 -- This is an obsolescent feature
1579 Check_Restriction (No_Obsolescent_Features, N);
1581 if Warn_On_Obsolescent_Feature then
1583 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1585 ("\use address attribute definition clause instead?", N);
1588 -- Rewrite as address clause
1591 Make_Attribute_Definition_Clause (Sloc (N),
1592 Name => Identifier (N),
1593 Chars => Name_Address,
1594 Expression => Expression (N)));
1596 -- We preserve Comes_From_Source, since logically the clause still
1597 -- comes from the source program even though it is changed in form.
1599 Set_Comes_From_Source (N, CS);
1601 -- Analyze rewritten clause
1603 Analyze_Attribute_Definition_Clause (N);
1604 end Analyze_At_Clause;
1606 -----------------------------------------
1607 -- Analyze_Attribute_Definition_Clause --
1608 -----------------------------------------
1610 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1611 Loc : constant Source_Ptr := Sloc (N);
1612 Nam : constant Node_Id := Name (N);
1613 Attr : constant Name_Id := Chars (N);
1614 Expr : constant Node_Id := Expression (N);
1615 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1618 -- The entity of Nam after it is analyzed. In the case of an incomplete
1619 -- type, this is the underlying type.
1622 -- The underlying entity to which the attribute applies. Generally this
1623 -- is the Underlying_Type of Ent, except in the case where the clause
1624 -- applies to full view of incomplete type or private type in which case
1625 -- U_Ent is just a copy of Ent.
1627 FOnly : Boolean := False;
1628 -- Reset to True for subtype specific attribute (Alignment, Size)
1629 -- and for stream attributes, i.e. those cases where in the call
1630 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1631 -- rules are checked. Note that the case of stream attributes is not
1632 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1633 -- disallow Storage_Size for derived task types, but that is also
1634 -- clearly unintentional.
1636 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1637 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1638 -- definition clauses.
1640 function Duplicate_Clause return Boolean;
1641 -- This routine checks if the aspect for U_Ent being given by attribute
1642 -- definition clause N is for an aspect that has already been specified,
1643 -- and if so gives an error message. If there is a duplicate, True is
1644 -- returned, otherwise if there is no error, False is returned.
1646 procedure Check_Indexing_Functions;
1647 -- Check that the function in Constant_Indexing or Variable_Indexing
1648 -- attribute has the proper type structure. If the name is overloaded,
1649 -- check that all interpretations are legal.
1651 procedure Check_Iterator_Functions;
1652 -- Check that there is a single function in Default_Iterator attribute
1653 -- has the proper type structure.
1655 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
1656 -- Common legality check for the previous two
1658 -----------------------------------
1659 -- Analyze_Stream_TSS_Definition --
1660 -----------------------------------
1662 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1663 Subp : Entity_Id := Empty;
1668 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1669 -- True for Read attribute, false for other attributes
1671 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1672 -- Return true if the entity is a subprogram with an appropriate
1673 -- profile for the attribute being defined.
1675 ----------------------
1676 -- Has_Good_Profile --
1677 ----------------------
1679 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1681 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1682 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1683 (False => E_Procedure, True => E_Function);
1687 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1691 F := First_Formal (Subp);
1694 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1695 or else Designated_Type (Etype (F)) /=
1696 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1701 if not Is_Function then
1705 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1706 (False => E_In_Parameter,
1707 True => E_Out_Parameter);
1709 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1717 Typ := Etype (Subp);
1720 return Base_Type (Typ) = Base_Type (Ent)
1721 and then No (Next_Formal (F));
1722 end Has_Good_Profile;
1724 -- Start of processing for Analyze_Stream_TSS_Definition
1729 if not Is_Type (U_Ent) then
1730 Error_Msg_N ("local name must be a subtype", Nam);
1734 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1736 -- If Pnam is present, it can be either inherited from an ancestor
1737 -- type (in which case it is legal to redefine it for this type), or
1738 -- be a previous definition of the attribute for the same type (in
1739 -- which case it is illegal).
1741 -- In the first case, it will have been analyzed already, and we
1742 -- can check that its profile does not match the expected profile
1743 -- for a stream attribute of U_Ent. In the second case, either Pnam
1744 -- has been analyzed (and has the expected profile), or it has not
1745 -- been analyzed yet (case of a type that has not been frozen yet
1746 -- and for which the stream attribute has been set using Set_TSS).
1749 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1751 Error_Msg_Sloc := Sloc (Pnam);
1752 Error_Msg_Name_1 := Attr;
1753 Error_Msg_N ("% attribute already defined #", Nam);
1759 if Is_Entity_Name (Expr) then
1760 if not Is_Overloaded (Expr) then
1761 if Has_Good_Profile (Entity (Expr)) then
1762 Subp := Entity (Expr);
1766 Get_First_Interp (Expr, I, It);
1767 while Present (It.Nam) loop
1768 if Has_Good_Profile (It.Nam) then
1773 Get_Next_Interp (I, It);
1778 if Present (Subp) then
1779 if Is_Abstract_Subprogram (Subp) then
1780 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1784 Set_Entity (Expr, Subp);
1785 Set_Etype (Expr, Etype (Subp));
1787 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1790 Error_Msg_Name_1 := Attr;
1791 Error_Msg_N ("incorrect expression for% attribute", Expr);
1793 end Analyze_Stream_TSS_Definition;
1795 ------------------------------
1796 -- Check_Indexing_Functions --
1797 ------------------------------
1799 procedure Check_Indexing_Functions is
1801 procedure Check_One_Function (Subp : Entity_Id);
1802 -- Check one possible interpretation
1804 ------------------------
1805 -- Check_One_Function --
1806 ------------------------
1808 procedure Check_One_Function (Subp : Entity_Id) is
1810 if not Check_Primitive_Function (Subp) then
1812 ("aspect Indexing requires a function that applies to type&",
1816 if not Has_Implicit_Dereference (Etype (Subp)) then
1818 ("function for indexing must return a reference type", Subp);
1820 end Check_One_Function;
1822 -- Start of processing for Check_Indexing_Functions
1831 if not Is_Overloaded (Expr) then
1832 Check_One_Function (Entity (Expr));
1840 Get_First_Interp (Expr, I, It);
1841 while Present (It.Nam) loop
1843 -- Note that analysis will have added the interpretation
1844 -- that corresponds to the dereference. We only check the
1845 -- subprogram itself.
1847 if Is_Overloadable (It.Nam) then
1848 Check_One_Function (It.Nam);
1851 Get_Next_Interp (I, It);
1855 end Check_Indexing_Functions;
1857 ------------------------------
1858 -- Check_Iterator_Functions --
1859 ------------------------------
1861 procedure Check_Iterator_Functions is
1862 Default : Entity_Id;
1864 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
1865 -- Check one possible interpretation for validity
1867 ----------------------------
1868 -- Valid_Default_Iterator --
1869 ----------------------------
1871 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
1875 if not Check_Primitive_Function (Subp) then
1878 Formal := First_Formal (Subp);
1881 -- False if any subsequent formal has no default expression
1883 Formal := Next_Formal (Formal);
1884 while Present (Formal) loop
1885 if No (Expression (Parent (Formal))) then
1889 Next_Formal (Formal);
1892 -- True if all subsequent formals have default expressions
1895 end Valid_Default_Iterator;
1897 -- Start of processing for Check_Iterator_Functions
1902 if not Is_Entity_Name (Expr) then
1903 Error_Msg_N ("aspect Iterator must be a function name", Expr);
1906 if not Is_Overloaded (Expr) then
1907 if not Check_Primitive_Function (Entity (Expr)) then
1909 ("aspect Indexing requires a function that applies to type&",
1910 Entity (Expr), Ent);
1913 if not Valid_Default_Iterator (Entity (Expr)) then
1914 Error_Msg_N ("improper function for default iterator", Expr);
1924 Get_First_Interp (Expr, I, It);
1925 while Present (It.Nam) loop
1926 if not Check_Primitive_Function (It.Nam)
1927 or else not Valid_Default_Iterator (It.Nam)
1931 elsif Present (Default) then
1932 Error_Msg_N ("default iterator must be unique", Expr);
1938 Get_Next_Interp (I, It);
1942 if Present (Default) then
1943 Set_Entity (Expr, Default);
1944 Set_Is_Overloaded (Expr, False);
1947 end Check_Iterator_Functions;
1949 -------------------------------
1950 -- Check_Primitive_Function --
1951 -------------------------------
1953 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
1957 if Ekind (Subp) /= E_Function then
1961 if No (First_Formal (Subp)) then
1964 Ctrl := Etype (First_Formal (Subp));
1968 or else Ctrl = Class_Wide_Type (Ent)
1970 (Ekind (Ctrl) = E_Anonymous_Access_Type
1972 (Designated_Type (Ctrl) = Ent
1973 or else Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
1982 end Check_Primitive_Function;
1984 ----------------------
1985 -- Duplicate_Clause --
1986 ----------------------
1988 function Duplicate_Clause return Boolean is
1992 -- Nothing to do if this attribute definition clause comes from
1993 -- an aspect specification, since we could not be duplicating an
1994 -- explicit clause, and we dealt with the case of duplicated aspects
1995 -- in Analyze_Aspect_Specifications.
1997 if From_Aspect_Specification (N) then
2001 -- Otherwise current clause may duplicate previous clause or a
2002 -- previously given aspect specification for the same aspect.
2004 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
2007 if Entity (A) = U_Ent then
2008 Error_Msg_Name_1 := Chars (N);
2009 Error_Msg_Sloc := Sloc (A);
2010 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
2016 end Duplicate_Clause;
2018 -- Start of processing for Analyze_Attribute_Definition_Clause
2021 -- The following code is a defense against recursion. Not clear that
2022 -- this can happen legitimately, but perhaps some error situations
2023 -- can cause it, and we did see this recursion during testing.
2025 if Analyzed (N) then
2028 Set_Analyzed (N, True);
2031 -- Process Ignore_Rep_Clauses option (we also ignore rep clauses in
2032 -- CodePeer mode or Alfa mode, since they are not relevant in these
2035 if Ignore_Rep_Clauses or CodePeer_Mode or Alfa_Mode then
2038 -- The following should be ignored. They do not affect legality
2039 -- and may be target dependent. The basic idea of -gnatI is to
2040 -- ignore any rep clauses that may be target dependent but do not
2041 -- affect legality (except possibly to be rejected because they
2042 -- are incompatible with the compilation target).
2044 when Attribute_Alignment |
2045 Attribute_Bit_Order |
2046 Attribute_Component_Size |
2047 Attribute_Machine_Radix |
2048 Attribute_Object_Size |
2050 Attribute_Stream_Size |
2051 Attribute_Value_Size =>
2052 Rewrite (N, Make_Null_Statement (Sloc (N)));
2055 -- We do not want too ignore 'Small in CodePeer_Mode or Alfa_Mode,
2056 -- since it has an impact on the exact computations performed.
2058 -- Perhaps 'Small should also not be ignored by
2059 -- Ignore_Rep_Clauses ???
2061 when Attribute_Small =>
2062 if Ignore_Rep_Clauses then
2063 Rewrite (N, Make_Null_Statement (Sloc (N)));
2067 -- The following should not be ignored, because in the first place
2068 -- they are reasonably portable, and should not cause problems in
2069 -- compiling code from another target, and also they do affect
2070 -- legality, e.g. failing to provide a stream attribute for a
2071 -- type may make a program illegal.
2073 when Attribute_External_Tag |
2077 Attribute_Storage_Pool |
2078 Attribute_Storage_Size |
2082 -- Other cases are errors ("attribute& cannot be set with
2083 -- definition clause"), which will be caught below.
2091 Ent := Entity (Nam);
2093 if Rep_Item_Too_Early (Ent, N) then
2097 -- Rep clause applies to full view of incomplete type or private type if
2098 -- we have one (if not, this is a premature use of the type). However,
2099 -- certain semantic checks need to be done on the specified entity (i.e.
2100 -- the private view), so we save it in Ent.
2102 if Is_Private_Type (Ent)
2103 and then Is_Derived_Type (Ent)
2104 and then not Is_Tagged_Type (Ent)
2105 and then No (Full_View (Ent))
2107 -- If this is a private type whose completion is a derivation from
2108 -- another private type, there is no full view, and the attribute
2109 -- belongs to the type itself, not its underlying parent.
2113 elsif Ekind (Ent) = E_Incomplete_Type then
2115 -- The attribute applies to the full view, set the entity of the
2116 -- attribute definition accordingly.
2118 Ent := Underlying_Type (Ent);
2120 Set_Entity (Nam, Ent);
2123 U_Ent := Underlying_Type (Ent);
2126 -- Complete other routine error checks
2128 if Etype (Nam) = Any_Type then
2131 elsif Scope (Ent) /= Current_Scope then
2132 Error_Msg_N ("entity must be declared in this scope", Nam);
2135 elsif No (U_Ent) then
2138 elsif Is_Type (U_Ent)
2139 and then not Is_First_Subtype (U_Ent)
2140 and then Id /= Attribute_Object_Size
2141 and then Id /= Attribute_Value_Size
2142 and then not From_At_Mod (N)
2144 Error_Msg_N ("cannot specify attribute for subtype", Nam);
2148 Set_Entity (N, U_Ent);
2150 -- Switch on particular attribute
2158 -- Address attribute definition clause
2160 when Attribute_Address => Address : begin
2162 -- A little error check, catch for X'Address use X'Address;
2164 if Nkind (Nam) = N_Identifier
2165 and then Nkind (Expr) = N_Attribute_Reference
2166 and then Attribute_Name (Expr) = Name_Address
2167 and then Nkind (Prefix (Expr)) = N_Identifier
2168 and then Chars (Nam) = Chars (Prefix (Expr))
2171 ("address for & is self-referencing", Prefix (Expr), Ent);
2175 -- Not that special case, carry on with analysis of expression
2177 Analyze_And_Resolve (Expr, RTE (RE_Address));
2179 -- Even when ignoring rep clauses we need to indicate that the
2180 -- entity has an address clause and thus it is legal to declare
2183 if Ignore_Rep_Clauses then
2184 if Ekind_In (U_Ent, E_Variable, E_Constant) then
2185 Record_Rep_Item (U_Ent, N);
2191 if Duplicate_Clause then
2194 -- Case of address clause for subprogram
2196 elsif Is_Subprogram (U_Ent) then
2197 if Has_Homonym (U_Ent) then
2199 ("address clause cannot be given " &
2200 "for overloaded subprogram",
2205 -- For subprograms, all address clauses are permitted, and we
2206 -- mark the subprogram as having a deferred freeze so that Gigi
2207 -- will not elaborate it too soon.
2209 -- Above needs more comments, what is too soon about???
2211 Set_Has_Delayed_Freeze (U_Ent);
2213 -- Case of address clause for entry
2215 elsif Ekind (U_Ent) = E_Entry then
2216 if Nkind (Parent (N)) = N_Task_Body then
2218 ("entry address must be specified in task spec", Nam);
2222 -- For entries, we require a constant address
2224 Check_Constant_Address_Clause (Expr, U_Ent);
2226 -- Special checks for task types
2228 if Is_Task_Type (Scope (U_Ent))
2229 and then Comes_From_Source (Scope (U_Ent))
2232 ("?entry address declared for entry in task type", N);
2234 ("\?only one task can be declared of this type", N);
2237 -- Entry address clauses are obsolescent
2239 Check_Restriction (No_Obsolescent_Features, N);
2241 if Warn_On_Obsolescent_Feature then
2243 ("attaching interrupt to task entry is an " &
2244 "obsolescent feature (RM J.7.1)?", N);
2246 ("\use interrupt procedure instead?", N);
2249 -- Case of an address clause for a controlled object which we
2250 -- consider to be erroneous.
2252 elsif Is_Controlled (Etype (U_Ent))
2253 or else Has_Controlled_Component (Etype (U_Ent))
2256 ("?controlled object& must not be overlaid", Nam, U_Ent);
2258 ("\?Program_Error will be raised at run time", Nam);
2259 Insert_Action (Declaration_Node (U_Ent),
2260 Make_Raise_Program_Error (Loc,
2261 Reason => PE_Overlaid_Controlled_Object));
2264 -- Case of address clause for a (non-controlled) object
2267 Ekind (U_Ent) = E_Variable
2269 Ekind (U_Ent) = E_Constant
2272 Expr : constant Node_Id := Expression (N);
2277 -- Exported variables cannot have an address clause, because
2278 -- this cancels the effect of the pragma Export.
2280 if Is_Exported (U_Ent) then
2282 ("cannot export object with address clause", Nam);
2286 Find_Overlaid_Entity (N, O_Ent, Off);
2288 -- Overlaying controlled objects is erroneous
2291 and then (Has_Controlled_Component (Etype (O_Ent))
2292 or else Is_Controlled (Etype (O_Ent)))
2295 ("?cannot overlay with controlled object", Expr);
2297 ("\?Program_Error will be raised at run time", Expr);
2298 Insert_Action (Declaration_Node (U_Ent),
2299 Make_Raise_Program_Error (Loc,
2300 Reason => PE_Overlaid_Controlled_Object));
2303 elsif Present (O_Ent)
2304 and then Ekind (U_Ent) = E_Constant
2305 and then not Is_Constant_Object (O_Ent)
2307 Error_Msg_N ("constant overlays a variable?", Expr);
2309 elsif Present (Renamed_Object (U_Ent)) then
2311 ("address clause not allowed"
2312 & " for a renaming declaration (RM 13.1(6))", Nam);
2315 -- Imported variables can have an address clause, but then
2316 -- the import is pretty meaningless except to suppress
2317 -- initializations, so we do not need such variables to
2318 -- be statically allocated (and in fact it causes trouble
2319 -- if the address clause is a local value).
2321 elsif Is_Imported (U_Ent) then
2322 Set_Is_Statically_Allocated (U_Ent, False);
2325 -- We mark a possible modification of a variable with an
2326 -- address clause, since it is likely aliasing is occurring.
2328 Note_Possible_Modification (Nam, Sure => False);
2330 -- Here we are checking for explicit overlap of one variable
2331 -- by another, and if we find this then mark the overlapped
2332 -- variable as also being volatile to prevent unwanted
2333 -- optimizations. This is a significant pessimization so
2334 -- avoid it when there is an offset, i.e. when the object
2335 -- is composite; they cannot be optimized easily anyway.
2338 and then Is_Object (O_Ent)
2341 Set_Treat_As_Volatile (O_Ent);
2344 -- Legality checks on the address clause for initialized
2345 -- objects is deferred until the freeze point, because
2346 -- a subsequent pragma might indicate that the object is
2347 -- imported and thus not initialized.
2349 Set_Has_Delayed_Freeze (U_Ent);
2351 -- If an initialization call has been generated for this
2352 -- object, it needs to be deferred to after the freeze node
2353 -- we have just now added, otherwise GIGI will see a
2354 -- reference to the variable (as actual to the IP call)
2355 -- before its definition.
2358 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
2360 if Present (Init_Call) then
2362 Append_Freeze_Action (U_Ent, Init_Call);
2366 if Is_Exported (U_Ent) then
2368 ("& cannot be exported if an address clause is given",
2371 ("\define and export a variable " &
2372 "that holds its address instead",
2376 -- Entity has delayed freeze, so we will generate an
2377 -- alignment check at the freeze point unless suppressed.
2379 if not Range_Checks_Suppressed (U_Ent)
2380 and then not Alignment_Checks_Suppressed (U_Ent)
2382 Set_Check_Address_Alignment (N);
2385 -- Kill the size check code, since we are not allocating
2386 -- the variable, it is somewhere else.
2388 Kill_Size_Check_Code (U_Ent);
2390 -- If the address clause is of the form:
2392 -- for Y'Address use X'Address
2396 -- Const : constant Address := X'Address;
2398 -- for Y'Address use Const;
2400 -- then we make an entry in the table for checking the size
2401 -- and alignment of the overlaying variable. We defer this
2402 -- check till after code generation to take full advantage
2403 -- of the annotation done by the back end. This entry is
2404 -- only made if the address clause comes from source.
2406 -- If the entity has a generic type, the check will be
2407 -- performed in the instance if the actual type justifies
2408 -- it, and we do not insert the clause in the table to
2409 -- prevent spurious warnings.
2411 if Address_Clause_Overlay_Warnings
2412 and then Comes_From_Source (N)
2413 and then Present (O_Ent)
2414 and then Is_Object (O_Ent)
2416 if not Is_Generic_Type (Etype (U_Ent)) then
2417 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
2420 -- If variable overlays a constant view, and we are
2421 -- warning on overlays, then mark the variable as
2422 -- overlaying a constant (we will give warnings later
2423 -- if this variable is assigned).
2425 if Is_Constant_Object (O_Ent)
2426 and then Ekind (U_Ent) = E_Variable
2428 Set_Overlays_Constant (U_Ent);
2433 -- Not a valid entity for an address clause
2436 Error_Msg_N ("address cannot be given for &", Nam);
2444 -- Alignment attribute definition clause
2446 when Attribute_Alignment => Alignment : declare
2447 Align : constant Uint := Get_Alignment_Value (Expr);
2452 if not Is_Type (U_Ent)
2453 and then Ekind (U_Ent) /= E_Variable
2454 and then Ekind (U_Ent) /= E_Constant
2456 Error_Msg_N ("alignment cannot be given for &", Nam);
2458 elsif Duplicate_Clause then
2461 elsif Align /= No_Uint then
2462 Set_Has_Alignment_Clause (U_Ent);
2463 Set_Alignment (U_Ent, Align);
2465 -- For an array type, U_Ent is the first subtype. In that case,
2466 -- also set the alignment of the anonymous base type so that
2467 -- other subtypes (such as the itypes for aggregates of the
2468 -- type) also receive the expected alignment.
2470 if Is_Array_Type (U_Ent) then
2471 Set_Alignment (Base_Type (U_Ent), Align);
2480 -- Bit_Order attribute definition clause
2482 when Attribute_Bit_Order => Bit_Order : declare
2484 if not Is_Record_Type (U_Ent) then
2486 ("Bit_Order can only be defined for record type", Nam);
2488 elsif Duplicate_Clause then
2492 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
2494 if Etype (Expr) = Any_Type then
2497 elsif not Is_Static_Expression (Expr) then
2498 Flag_Non_Static_Expr
2499 ("Bit_Order requires static expression!", Expr);
2502 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
2503 Set_Reverse_Bit_Order (U_Ent, True);
2509 --------------------
2510 -- Component_Size --
2511 --------------------
2513 -- Component_Size attribute definition clause
2515 when Attribute_Component_Size => Component_Size_Case : declare
2516 Csize : constant Uint := Static_Integer (Expr);
2520 New_Ctyp : Entity_Id;
2524 if not Is_Array_Type (U_Ent) then
2525 Error_Msg_N ("component size requires array type", Nam);
2529 Btype := Base_Type (U_Ent);
2530 Ctyp := Component_Type (Btype);
2532 if Duplicate_Clause then
2535 elsif Rep_Item_Too_Early (Btype, N) then
2538 elsif Csize /= No_Uint then
2539 Check_Size (Expr, Ctyp, Csize, Biased);
2541 -- For the biased case, build a declaration for a subtype that
2542 -- will be used to represent the biased subtype that reflects
2543 -- the biased representation of components. We need the subtype
2544 -- to get proper conversions on referencing elements of the
2545 -- array. Note: component size clauses are ignored in VM mode.
2547 if VM_Target = No_VM then
2550 Make_Defining_Identifier (Loc,
2552 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2555 Make_Subtype_Declaration (Loc,
2556 Defining_Identifier => New_Ctyp,
2557 Subtype_Indication =>
2558 New_Occurrence_Of (Component_Type (Btype), Loc));
2560 Set_Parent (Decl, N);
2561 Analyze (Decl, Suppress => All_Checks);
2563 Set_Has_Delayed_Freeze (New_Ctyp, False);
2564 Set_Esize (New_Ctyp, Csize);
2565 Set_RM_Size (New_Ctyp, Csize);
2566 Init_Alignment (New_Ctyp);
2567 Set_Is_Itype (New_Ctyp, True);
2568 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2570 Set_Component_Type (Btype, New_Ctyp);
2571 Set_Biased (New_Ctyp, N, "component size clause");
2574 Set_Component_Size (Btype, Csize);
2576 -- For VM case, we ignore component size clauses
2579 -- Give a warning unless we are in GNAT mode, in which case
2580 -- the warning is suppressed since it is not useful.
2582 if not GNAT_Mode then
2584 ("?component size ignored in this configuration", N);
2588 -- Deal with warning on overridden size
2590 if Warn_On_Overridden_Size
2591 and then Has_Size_Clause (Ctyp)
2592 and then RM_Size (Ctyp) /= Csize
2595 ("?component size overrides size clause for&",
2599 Set_Has_Component_Size_Clause (Btype, True);
2600 Set_Has_Non_Standard_Rep (Btype, True);
2602 end Component_Size_Case;
2604 -----------------------
2605 -- Constant_Indexing --
2606 -----------------------
2608 when Attribute_Constant_Indexing =>
2609 Check_Indexing_Functions;
2611 ----------------------
2612 -- Default_Iterator --
2613 ----------------------
2615 when Attribute_Default_Iterator => Default_Iterator : declare
2619 if not Is_Tagged_Type (U_Ent) then
2621 ("aspect Default_Iterator applies to tagged type", Nam);
2624 Check_Iterator_Functions;
2628 if not Is_Entity_Name (Expr)
2629 or else Ekind (Entity (Expr)) /= E_Function
2631 Error_Msg_N ("aspect Iterator must be a function", Expr);
2633 Func := Entity (Expr);
2636 if No (First_Formal (Func))
2637 or else Etype (First_Formal (Func)) /= U_Ent
2640 ("Default Iterator must be a primitive of&", Func, U_Ent);
2642 end Default_Iterator;
2648 when Attribute_External_Tag => External_Tag :
2650 if not Is_Tagged_Type (U_Ent) then
2651 Error_Msg_N ("should be a tagged type", Nam);
2654 if Duplicate_Clause then
2658 Analyze_And_Resolve (Expr, Standard_String);
2660 if not Is_Static_Expression (Expr) then
2661 Flag_Non_Static_Expr
2662 ("static string required for tag name!", Nam);
2665 if VM_Target = No_VM then
2666 Set_Has_External_Tag_Rep_Clause (U_Ent);
2668 Error_Msg_Name_1 := Attr;
2670 ("% attribute unsupported in this configuration", Nam);
2673 if not Is_Library_Level_Entity (U_Ent) then
2675 ("?non-unique external tag supplied for &", N, U_Ent);
2677 ("?\same external tag applies to all subprogram calls", N);
2679 ("?\corresponding internal tag cannot be obtained", N);
2684 --------------------------
2685 -- Implicit_Dereference --
2686 --------------------------
2688 when Attribute_Implicit_Dereference =>
2690 -- Legality checks already performed at the point of
2691 -- the type declaration, aspect is not delayed.
2699 when Attribute_Input =>
2700 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2701 Set_Has_Specified_Stream_Input (Ent);
2703 ----------------------
2704 -- Iterator_Element --
2705 ----------------------
2707 when Attribute_Iterator_Element =>
2710 if not Is_Entity_Name (Expr)
2711 or else not Is_Type (Entity (Expr))
2713 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
2720 -- Machine radix attribute definition clause
2722 when Attribute_Machine_Radix => Machine_Radix : declare
2723 Radix : constant Uint := Static_Integer (Expr);
2726 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2727 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2729 elsif Duplicate_Clause then
2732 elsif Radix /= No_Uint then
2733 Set_Has_Machine_Radix_Clause (U_Ent);
2734 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2738 elsif Radix = 10 then
2739 Set_Machine_Radix_10 (U_Ent);
2741 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2750 -- Object_Size attribute definition clause
2752 when Attribute_Object_Size => Object_Size : declare
2753 Size : constant Uint := Static_Integer (Expr);
2756 pragma Warnings (Off, Biased);
2759 if not Is_Type (U_Ent) then
2760 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2762 elsif Duplicate_Clause then
2766 Check_Size (Expr, U_Ent, Size, Biased);
2774 UI_Mod (Size, 64) /= 0
2777 ("Object_Size must be 8, 16, 32, or multiple of 64",
2781 Set_Esize (U_Ent, Size);
2782 Set_Has_Object_Size_Clause (U_Ent);
2783 Alignment_Check_For_Size_Change (U_Ent, Size);
2791 when Attribute_Output =>
2792 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2793 Set_Has_Specified_Stream_Output (Ent);
2799 when Attribute_Read =>
2800 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2801 Set_Has_Specified_Stream_Read (Ent);
2807 -- Size attribute definition clause
2809 when Attribute_Size => Size : declare
2810 Size : constant Uint := Static_Integer (Expr);
2817 if Duplicate_Clause then
2820 elsif not Is_Type (U_Ent)
2821 and then Ekind (U_Ent) /= E_Variable
2822 and then Ekind (U_Ent) /= E_Constant
2824 Error_Msg_N ("size cannot be given for &", Nam);
2826 elsif Is_Array_Type (U_Ent)
2827 and then not Is_Constrained (U_Ent)
2830 ("size cannot be given for unconstrained array", Nam);
2832 elsif Size /= No_Uint then
2833 if VM_Target /= No_VM and then not GNAT_Mode then
2835 -- Size clause is not handled properly on VM targets.
2836 -- Display a warning unless we are in GNAT mode, in which
2837 -- case this is useless.
2840 ("?size clauses are ignored in this configuration", N);
2843 if Is_Type (U_Ent) then
2846 Etyp := Etype (U_Ent);
2849 -- Check size, note that Gigi is in charge of checking that the
2850 -- size of an array or record type is OK. Also we do not check
2851 -- the size in the ordinary fixed-point case, since it is too
2852 -- early to do so (there may be subsequent small clause that
2853 -- affects the size). We can check the size if a small clause
2854 -- has already been given.
2856 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2857 or else Has_Small_Clause (U_Ent)
2859 Check_Size (Expr, Etyp, Size, Biased);
2860 Set_Biased (U_Ent, N, "size clause", Biased);
2863 -- For types set RM_Size and Esize if possible
2865 if Is_Type (U_Ent) then
2866 Set_RM_Size (U_Ent, Size);
2868 -- For elementary types, increase Object_Size to power of 2,
2869 -- but not less than a storage unit in any case (normally
2870 -- this means it will be byte addressable).
2872 -- For all other types, nothing else to do, we leave Esize
2873 -- (object size) unset, the back end will set it from the
2874 -- size and alignment in an appropriate manner.
2876 -- In both cases, we check whether the alignment must be
2877 -- reset in the wake of the size change.
2879 if Is_Elementary_Type (U_Ent) then
2880 if Size <= System_Storage_Unit then
2881 Init_Esize (U_Ent, System_Storage_Unit);
2882 elsif Size <= 16 then
2883 Init_Esize (U_Ent, 16);
2884 elsif Size <= 32 then
2885 Init_Esize (U_Ent, 32);
2887 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2890 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
2892 Alignment_Check_For_Size_Change (U_Ent, Size);
2895 -- For objects, set Esize only
2898 if Is_Elementary_Type (Etyp) then
2899 if Size /= System_Storage_Unit
2901 Size /= System_Storage_Unit * 2
2903 Size /= System_Storage_Unit * 4
2905 Size /= System_Storage_Unit * 8
2907 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2908 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2910 ("size for primitive object must be a power of 2"
2911 & " in the range ^-^", N);
2915 Set_Esize (U_Ent, Size);
2918 Set_Has_Size_Clause (U_Ent);
2926 -- Small attribute definition clause
2928 when Attribute_Small => Small : declare
2929 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2933 Analyze_And_Resolve (Expr, Any_Real);
2935 if Etype (Expr) = Any_Type then
2938 elsif not Is_Static_Expression (Expr) then
2939 Flag_Non_Static_Expr
2940 ("small requires static expression!", Expr);
2944 Small := Expr_Value_R (Expr);
2946 if Small <= Ureal_0 then
2947 Error_Msg_N ("small value must be greater than zero", Expr);
2953 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2955 ("small requires an ordinary fixed point type", Nam);
2957 elsif Has_Small_Clause (U_Ent) then
2958 Error_Msg_N ("small already given for &", Nam);
2960 elsif Small > Delta_Value (U_Ent) then
2962 ("small value must not be greater then delta value", Nam);
2965 Set_Small_Value (U_Ent, Small);
2966 Set_Small_Value (Implicit_Base, Small);
2967 Set_Has_Small_Clause (U_Ent);
2968 Set_Has_Small_Clause (Implicit_Base);
2969 Set_Has_Non_Standard_Rep (Implicit_Base);
2977 -- Storage_Pool attribute definition clause
2979 when Attribute_Storage_Pool => Storage_Pool : declare
2984 if Ekind (U_Ent) = E_Access_Subprogram_Type then
2986 ("storage pool cannot be given for access-to-subprogram type",
2991 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
2994 ("storage pool can only be given for access types", Nam);
2997 elsif Is_Derived_Type (U_Ent) then
2999 ("storage pool cannot be given for a derived access type",
3002 elsif Duplicate_Clause then
3005 elsif Present (Associated_Storage_Pool (U_Ent)) then
3006 Error_Msg_N ("storage pool already given for &", Nam);
3011 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
3013 if not Denotes_Variable (Expr) then
3014 Error_Msg_N ("storage pool must be a variable", Expr);
3018 if Nkind (Expr) = N_Type_Conversion then
3019 T := Etype (Expression (Expr));
3024 -- The Stack_Bounded_Pool is used internally for implementing
3025 -- access types with a Storage_Size. Since it only work properly
3026 -- when used on one specific type, we need to check that it is not
3027 -- hijacked improperly:
3029 -- type T is access Integer;
3030 -- for T'Storage_Size use n;
3031 -- type Q is access Float;
3032 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
3034 if RTE_Available (RE_Stack_Bounded_Pool)
3035 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
3037 Error_Msg_N ("non-shareable internal Pool", Expr);
3041 -- If the argument is a name that is not an entity name, then
3042 -- we construct a renaming operation to define an entity of
3043 -- type storage pool.
3045 if not Is_Entity_Name (Expr)
3046 and then Is_Object_Reference (Expr)
3048 Pool := Make_Temporary (Loc, 'P', Expr);
3051 Rnode : constant Node_Id :=
3052 Make_Object_Renaming_Declaration (Loc,
3053 Defining_Identifier => Pool,
3055 New_Occurrence_Of (Etype (Expr), Loc),
3059 Insert_Before (N, Rnode);
3061 Set_Associated_Storage_Pool (U_Ent, Pool);
3064 elsif Is_Entity_Name (Expr) then
3065 Pool := Entity (Expr);
3067 -- If pool is a renamed object, get original one. This can
3068 -- happen with an explicit renaming, and within instances.
3070 while Present (Renamed_Object (Pool))
3071 and then Is_Entity_Name (Renamed_Object (Pool))
3073 Pool := Entity (Renamed_Object (Pool));
3076 if Present (Renamed_Object (Pool))
3077 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
3078 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
3080 Pool := Entity (Expression (Renamed_Object (Pool)));
3083 Set_Associated_Storage_Pool (U_Ent, Pool);
3085 elsif Nkind (Expr) = N_Type_Conversion
3086 and then Is_Entity_Name (Expression (Expr))
3087 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
3089 Pool := Entity (Expression (Expr));
3090 Set_Associated_Storage_Pool (U_Ent, Pool);
3093 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
3102 -- Storage_Size attribute definition clause
3104 when Attribute_Storage_Size => Storage_Size : declare
3105 Btype : constant Entity_Id := Base_Type (U_Ent);
3109 if Is_Task_Type (U_Ent) then
3110 Check_Restriction (No_Obsolescent_Features, N);
3112 if Warn_On_Obsolescent_Feature then
3114 ("storage size clause for task is an " &
3115 "obsolescent feature (RM J.9)?", N);
3116 Error_Msg_N ("\use Storage_Size pragma instead?", N);
3122 if not Is_Access_Type (U_Ent)
3123 and then Ekind (U_Ent) /= E_Task_Type
3125 Error_Msg_N ("storage size cannot be given for &", Nam);
3127 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
3129 ("storage size cannot be given for a derived access type",
3132 elsif Duplicate_Clause then
3136 Analyze_And_Resolve (Expr, Any_Integer);
3138 if Is_Access_Type (U_Ent) then
3139 if Present (Associated_Storage_Pool (U_Ent)) then
3140 Error_Msg_N ("storage pool already given for &", Nam);
3144 if Is_OK_Static_Expression (Expr)
3145 and then Expr_Value (Expr) = 0
3147 Set_No_Pool_Assigned (Btype);
3150 else -- Is_Task_Type (U_Ent)
3151 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
3153 if Present (Sprag) then
3154 Error_Msg_Sloc := Sloc (Sprag);
3156 ("Storage_Size already specified#", Nam);
3161 Set_Has_Storage_Size_Clause (Btype);
3169 when Attribute_Stream_Size => Stream_Size : declare
3170 Size : constant Uint := Static_Integer (Expr);
3173 if Ada_Version <= Ada_95 then
3174 Check_Restriction (No_Implementation_Attributes, N);
3177 if Duplicate_Clause then
3180 elsif Is_Elementary_Type (U_Ent) then
3181 if Size /= System_Storage_Unit
3183 Size /= System_Storage_Unit * 2
3185 Size /= System_Storage_Unit * 4
3187 Size /= System_Storage_Unit * 8
3189 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
3191 ("stream size for elementary type must be a"
3192 & " power of 2 and at least ^", N);
3194 elsif RM_Size (U_Ent) > Size then
3195 Error_Msg_Uint_1 := RM_Size (U_Ent);
3197 ("stream size for elementary type must be a"
3198 & " power of 2 and at least ^", N);
3201 Set_Has_Stream_Size_Clause (U_Ent);
3204 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
3212 -- Value_Size attribute definition clause
3214 when Attribute_Value_Size => Value_Size : declare
3215 Size : constant Uint := Static_Integer (Expr);
3219 if not Is_Type (U_Ent) then
3220 Error_Msg_N ("Value_Size cannot be given for &", Nam);
3222 elsif Duplicate_Clause then
3225 elsif Is_Array_Type (U_Ent)
3226 and then not Is_Constrained (U_Ent)
3229 ("Value_Size cannot be given for unconstrained array", Nam);
3232 if Is_Elementary_Type (U_Ent) then
3233 Check_Size (Expr, U_Ent, Size, Biased);
3234 Set_Biased (U_Ent, N, "value size clause", Biased);
3237 Set_RM_Size (U_Ent, Size);
3241 -----------------------
3242 -- Variable_Indexing --
3243 -----------------------
3245 when Attribute_Variable_Indexing =>
3246 Check_Indexing_Functions;
3252 when Attribute_Write =>
3253 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
3254 Set_Has_Specified_Stream_Write (Ent);
3256 -- All other attributes cannot be set
3260 ("attribute& cannot be set with definition clause", N);
3263 -- The test for the type being frozen must be performed after any
3264 -- expression the clause has been analyzed since the expression itself
3265 -- might cause freezing that makes the clause illegal.
3267 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
3270 end Analyze_Attribute_Definition_Clause;
3272 ----------------------------
3273 -- Analyze_Code_Statement --
3274 ----------------------------
3276 procedure Analyze_Code_Statement (N : Node_Id) is
3277 HSS : constant Node_Id := Parent (N);
3278 SBody : constant Node_Id := Parent (HSS);
3279 Subp : constant Entity_Id := Current_Scope;
3286 -- Analyze and check we get right type, note that this implements the
3287 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
3288 -- is the only way that Asm_Insn could possibly be visible.
3290 Analyze_And_Resolve (Expression (N));
3292 if Etype (Expression (N)) = Any_Type then
3294 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
3295 Error_Msg_N ("incorrect type for code statement", N);
3299 Check_Code_Statement (N);
3301 -- Make sure we appear in the handled statement sequence of a
3302 -- subprogram (RM 13.8(3)).
3304 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
3305 or else Nkind (SBody) /= N_Subprogram_Body
3308 ("code statement can only appear in body of subprogram", N);
3312 -- Do remaining checks (RM 13.8(3)) if not already done
3314 if not Is_Machine_Code_Subprogram (Subp) then
3315 Set_Is_Machine_Code_Subprogram (Subp);
3317 -- No exception handlers allowed
3319 if Present (Exception_Handlers (HSS)) then
3321 ("exception handlers not permitted in machine code subprogram",
3322 First (Exception_Handlers (HSS)));
3325 -- No declarations other than use clauses and pragmas (we allow
3326 -- certain internally generated declarations as well).
3328 Decl := First (Declarations (SBody));
3329 while Present (Decl) loop
3330 DeclO := Original_Node (Decl);
3331 if Comes_From_Source (DeclO)
3332 and not Nkind_In (DeclO, N_Pragma,
3333 N_Use_Package_Clause,
3335 N_Implicit_Label_Declaration)
3338 ("this declaration not allowed in machine code subprogram",
3345 -- No statements other than code statements, pragmas, and labels.
3346 -- Again we allow certain internally generated statements.
3348 Stmt := First (Statements (HSS));
3349 while Present (Stmt) loop
3350 StmtO := Original_Node (Stmt);
3351 if Comes_From_Source (StmtO)
3352 and then not Nkind_In (StmtO, N_Pragma,
3357 ("this statement is not allowed in machine code subprogram",
3364 end Analyze_Code_Statement;
3366 -----------------------------------------------
3367 -- Analyze_Enumeration_Representation_Clause --
3368 -----------------------------------------------
3370 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
3371 Ident : constant Node_Id := Identifier (N);
3372 Aggr : constant Node_Id := Array_Aggregate (N);
3373 Enumtype : Entity_Id;
3380 Err : Boolean := False;
3381 -- Set True to avoid cascade errors and crashes on incorrect source code
3383 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
3384 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
3385 -- Allowed range of universal integer (= allowed range of enum lit vals)
3389 -- Minimum and maximum values of entries
3392 -- Pointer to node for literal providing max value
3395 if Ignore_Rep_Clauses then
3399 -- First some basic error checks
3402 Enumtype := Entity (Ident);
3404 if Enumtype = Any_Type
3405 or else Rep_Item_Too_Early (Enumtype, N)
3409 Enumtype := Underlying_Type (Enumtype);
3412 if not Is_Enumeration_Type (Enumtype) then
3414 ("enumeration type required, found}",
3415 Ident, First_Subtype (Enumtype));
3419 -- Ignore rep clause on generic actual type. This will already have
3420 -- been flagged on the template as an error, and this is the safest
3421 -- way to ensure we don't get a junk cascaded message in the instance.
3423 if Is_Generic_Actual_Type (Enumtype) then
3426 -- Type must be in current scope
3428 elsif Scope (Enumtype) /= Current_Scope then
3429 Error_Msg_N ("type must be declared in this scope", Ident);
3432 -- Type must be a first subtype
3434 elsif not Is_First_Subtype (Enumtype) then
3435 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
3438 -- Ignore duplicate rep clause
3440 elsif Has_Enumeration_Rep_Clause (Enumtype) then
3441 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
3444 -- Don't allow rep clause for standard [wide_[wide_]]character
3446 elsif Is_Standard_Character_Type (Enumtype) then
3447 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
3450 -- Check that the expression is a proper aggregate (no parentheses)
3452 elsif Paren_Count (Aggr) /= 0 then
3454 ("extra parentheses surrounding aggregate not allowed",
3458 -- All tests passed, so set rep clause in place
3461 Set_Has_Enumeration_Rep_Clause (Enumtype);
3462 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
3465 -- Now we process the aggregate. Note that we don't use the normal
3466 -- aggregate code for this purpose, because we don't want any of the
3467 -- normal expansion activities, and a number of special semantic
3468 -- rules apply (including the component type being any integer type)
3470 Elit := First_Literal (Enumtype);
3472 -- First the positional entries if any
3474 if Present (Expressions (Aggr)) then
3475 Expr := First (Expressions (Aggr));
3476 while Present (Expr) loop
3478 Error_Msg_N ("too many entries in aggregate", Expr);
3482 Val := Static_Integer (Expr);
3484 -- Err signals that we found some incorrect entries processing
3485 -- the list. The final checks for completeness and ordering are
3486 -- skipped in this case.
3488 if Val = No_Uint then
3490 elsif Val < Lo or else Hi < Val then
3491 Error_Msg_N ("value outside permitted range", Expr);
3495 Set_Enumeration_Rep (Elit, Val);
3496 Set_Enumeration_Rep_Expr (Elit, Expr);
3502 -- Now process the named entries if present
3504 if Present (Component_Associations (Aggr)) then
3505 Assoc := First (Component_Associations (Aggr));
3506 while Present (Assoc) loop
3507 Choice := First (Choices (Assoc));
3509 if Present (Next (Choice)) then
3511 ("multiple choice not allowed here", Next (Choice));
3515 if Nkind (Choice) = N_Others_Choice then
3516 Error_Msg_N ("others choice not allowed here", Choice);
3519 elsif Nkind (Choice) = N_Range then
3521 -- ??? should allow zero/one element range here
3523 Error_Msg_N ("range not allowed here", Choice);
3527 Analyze_And_Resolve (Choice, Enumtype);
3529 if Error_Posted (Choice) then
3534 if Is_Entity_Name (Choice)
3535 and then Is_Type (Entity (Choice))
3537 Error_Msg_N ("subtype name not allowed here", Choice);
3540 -- ??? should allow static subtype with zero/one entry
3542 elsif Etype (Choice) = Base_Type (Enumtype) then
3543 if not Is_Static_Expression (Choice) then
3544 Flag_Non_Static_Expr
3545 ("non-static expression used for choice!", Choice);
3549 Elit := Expr_Value_E (Choice);
3551 if Present (Enumeration_Rep_Expr (Elit)) then
3553 Sloc (Enumeration_Rep_Expr (Elit));
3555 ("representation for& previously given#",
3560 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
3562 Expr := Expression (Assoc);
3563 Val := Static_Integer (Expr);
3565 if Val = No_Uint then
3568 elsif Val < Lo or else Hi < Val then
3569 Error_Msg_N ("value outside permitted range", Expr);
3573 Set_Enumeration_Rep (Elit, Val);
3583 -- Aggregate is fully processed. Now we check that a full set of
3584 -- representations was given, and that they are in range and in order.
3585 -- These checks are only done if no other errors occurred.
3591 Elit := First_Literal (Enumtype);
3592 while Present (Elit) loop
3593 if No (Enumeration_Rep_Expr (Elit)) then
3594 Error_Msg_NE ("missing representation for&!", N, Elit);
3597 Val := Enumeration_Rep (Elit);
3599 if Min = No_Uint then
3603 if Val /= No_Uint then
3604 if Max /= No_Uint and then Val <= Max then
3606 ("enumeration value for& not ordered!",
3607 Enumeration_Rep_Expr (Elit), Elit);
3610 Max_Node := Enumeration_Rep_Expr (Elit);
3614 -- If there is at least one literal whose representation is not
3615 -- equal to the Pos value, then note that this enumeration type
3616 -- has a non-standard representation.
3618 if Val /= Enumeration_Pos (Elit) then
3619 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3626 -- Now set proper size information
3629 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3632 if Has_Size_Clause (Enumtype) then
3634 -- All OK, if size is OK now
3636 if RM_Size (Enumtype) >= Minsize then
3640 -- Try if we can get by with biasing
3643 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3645 -- Error message if even biasing does not work
3647 if RM_Size (Enumtype) < Minsize then
3648 Error_Msg_Uint_1 := RM_Size (Enumtype);
3649 Error_Msg_Uint_2 := Max;
3651 ("previously given size (^) is too small "
3652 & "for this value (^)", Max_Node);
3654 -- If biasing worked, indicate that we now have biased rep
3658 (Enumtype, Size_Clause (Enumtype), "size clause");
3663 Set_RM_Size (Enumtype, Minsize);
3664 Set_Enum_Esize (Enumtype);
3667 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3668 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3669 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3673 -- We repeat the too late test in case it froze itself!
3675 if Rep_Item_Too_Late (Enumtype, N) then
3678 end Analyze_Enumeration_Representation_Clause;
3680 ----------------------------
3681 -- Analyze_Free_Statement --
3682 ----------------------------
3684 procedure Analyze_Free_Statement (N : Node_Id) is
3686 Analyze (Expression (N));
3687 end Analyze_Free_Statement;
3689 ---------------------------
3690 -- Analyze_Freeze_Entity --
3691 ---------------------------
3693 procedure Analyze_Freeze_Entity (N : Node_Id) is
3694 E : constant Entity_Id := Entity (N);
3697 -- Remember that we are processing a freezing entity. Required to
3698 -- ensure correct decoration of internal entities associated with
3699 -- interfaces (see New_Overloaded_Entity).
3701 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3703 -- For tagged types covering interfaces add internal entities that link
3704 -- the primitives of the interfaces with the primitives that cover them.
3705 -- Note: These entities were originally generated only when generating
3706 -- code because their main purpose was to provide support to initialize
3707 -- the secondary dispatch tables. They are now generated also when
3708 -- compiling with no code generation to provide ASIS the relationship
3709 -- between interface primitives and tagged type primitives. They are
3710 -- also used to locate primitives covering interfaces when processing
3711 -- generics (see Derive_Subprograms).
3713 if Ada_Version >= Ada_2005
3714 and then Ekind (E) = E_Record_Type
3715 and then Is_Tagged_Type (E)
3716 and then not Is_Interface (E)
3717 and then Has_Interfaces (E)
3719 -- This would be a good common place to call the routine that checks
3720 -- overriding of interface primitives (and thus factorize calls to
3721 -- Check_Abstract_Overriding located at different contexts in the
3722 -- compiler). However, this is not possible because it causes
3723 -- spurious errors in case of late overriding.
3725 Add_Internal_Interface_Entities (E);
3730 if Ekind (E) = E_Record_Type
3731 and then Is_CPP_Class (E)
3732 and then Is_Tagged_Type (E)
3733 and then Tagged_Type_Expansion
3734 and then Expander_Active
3736 if CPP_Num_Prims (E) = 0 then
3738 -- If the CPP type has user defined components then it must import
3739 -- primitives from C++. This is required because if the C++ class
3740 -- has no primitives then the C++ compiler does not added the _tag
3741 -- component to the type.
3743 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3745 if First_Entity (E) /= Last_Entity (E) then
3747 ("?'C'P'P type must import at least one primitive from C++",
3752 -- Check that all its primitives are abstract or imported from C++.
3753 -- Check also availability of the C++ constructor.
3756 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3758 Error_Reported : Boolean := False;
3762 Elmt := First_Elmt (Primitive_Operations (E));
3763 while Present (Elmt) loop
3764 Prim := Node (Elmt);
3766 if Comes_From_Source (Prim) then
3767 if Is_Abstract_Subprogram (Prim) then
3770 elsif not Is_Imported (Prim)
3771 or else Convention (Prim) /= Convention_CPP
3774 ("?primitives of 'C'P'P types must be imported from C++"
3775 & " or abstract", Prim);
3777 elsif not Has_Constructors
3778 and then not Error_Reported
3780 Error_Msg_Name_1 := Chars (E);
3782 ("?'C'P'P constructor required for type %", Prim);
3783 Error_Reported := True;
3792 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3794 -- If we have a type with predicates, build predicate function
3796 if Is_Type (E) and then Has_Predicates (E) then
3797 Build_Predicate_Function (E, N);
3800 -- If type has delayed aspects, this is where we do the preanalysis at
3801 -- the freeze point, as part of the consistent visibility check. Note
3802 -- that this must be done after calling Build_Predicate_Function or
3803 -- Build_Invariant_Procedure since these subprograms fix occurrences of
3804 -- the subtype name in the saved expression so that they will not cause
3805 -- trouble in the preanalysis.
3807 if Has_Delayed_Aspects (E) then
3812 -- Look for aspect specification entries for this entity
3814 Ritem := First_Rep_Item (E);
3815 while Present (Ritem) loop
3816 if Nkind (Ritem) = N_Aspect_Specification
3817 and then Entity (Ritem) = E
3818 and then Is_Delayed_Aspect (Ritem)
3819 and then Scope (E) = Current_Scope
3821 Check_Aspect_At_Freeze_Point (Ritem);
3824 Next_Rep_Item (Ritem);
3828 end Analyze_Freeze_Entity;
3830 ------------------------------------------
3831 -- Analyze_Record_Representation_Clause --
3832 ------------------------------------------
3834 -- Note: we check as much as we can here, but we can't do any checks
3835 -- based on the position values (e.g. overlap checks) until freeze time
3836 -- because especially in Ada 2005 (machine scalar mode), the processing
3837 -- for non-standard bit order can substantially change the positions.
3838 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3839 -- for the remainder of this processing.
3841 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3842 Ident : constant Node_Id := Identifier (N);
3847 Hbit : Uint := Uint_0;
3851 Rectype : Entity_Id;
3853 CR_Pragma : Node_Id := Empty;
3854 -- Points to N_Pragma node if Complete_Representation pragma present
3857 if Ignore_Rep_Clauses then
3862 Rectype := Entity (Ident);
3864 if Rectype = Any_Type
3865 or else Rep_Item_Too_Early (Rectype, N)
3869 Rectype := Underlying_Type (Rectype);
3872 -- First some basic error checks
3874 if not Is_Record_Type (Rectype) then
3876 ("record type required, found}", Ident, First_Subtype (Rectype));
3879 elsif Scope (Rectype) /= Current_Scope then
3880 Error_Msg_N ("type must be declared in this scope", N);
3883 elsif not Is_First_Subtype (Rectype) then
3884 Error_Msg_N ("cannot give record rep clause for subtype", N);
3887 elsif Has_Record_Rep_Clause (Rectype) then
3888 Error_Msg_N ("duplicate record rep clause ignored", N);
3891 elsif Rep_Item_Too_Late (Rectype, N) then
3895 if Present (Mod_Clause (N)) then
3897 Loc : constant Source_Ptr := Sloc (N);
3898 M : constant Node_Id := Mod_Clause (N);
3899 P : constant List_Id := Pragmas_Before (M);
3903 pragma Warnings (Off, Mod_Val);
3906 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3908 if Warn_On_Obsolescent_Feature then
3910 ("mod clause is an obsolescent feature (RM J.8)?", N);
3912 ("\use alignment attribute definition clause instead?", N);
3919 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3920 -- the Mod clause into an alignment clause anyway, so that the
3921 -- back-end can compute and back-annotate properly the size and
3922 -- alignment of types that may include this record.
3924 -- This seems dubious, this destroys the source tree in a manner
3925 -- not detectable by ASIS ???
3927 if Operating_Mode = Check_Semantics and then ASIS_Mode then
3929 Make_Attribute_Definition_Clause (Loc,
3930 Name => New_Reference_To (Base_Type (Rectype), Loc),
3931 Chars => Name_Alignment,
3932 Expression => Relocate_Node (Expression (M)));
3934 Set_From_At_Mod (AtM_Nod);
3935 Insert_After (N, AtM_Nod);
3936 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3937 Set_Mod_Clause (N, Empty);
3940 -- Get the alignment value to perform error checking
3942 Mod_Val := Get_Alignment_Value (Expression (M));
3947 -- For untagged types, clear any existing component clauses for the
3948 -- type. If the type is derived, this is what allows us to override
3949 -- a rep clause for the parent. For type extensions, the representation
3950 -- of the inherited components is inherited, so we want to keep previous
3951 -- component clauses for completeness.
3953 if not Is_Tagged_Type (Rectype) then
3954 Comp := First_Component_Or_Discriminant (Rectype);
3955 while Present (Comp) loop
3956 Set_Component_Clause (Comp, Empty);
3957 Next_Component_Or_Discriminant (Comp);
3961 -- All done if no component clauses
3963 CC := First (Component_Clauses (N));
3969 -- A representation like this applies to the base type
3971 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3972 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3973 Set_Has_Specified_Layout (Base_Type (Rectype));
3975 -- Process the component clauses
3977 while Present (CC) loop
3981 if Nkind (CC) = N_Pragma then
3984 -- The only pragma of interest is Complete_Representation
3986 if Pragma_Name (CC) = Name_Complete_Representation then
3990 -- Processing for real component clause
3993 Posit := Static_Integer (Position (CC));
3994 Fbit := Static_Integer (First_Bit (CC));
3995 Lbit := Static_Integer (Last_Bit (CC));
3998 and then Fbit /= No_Uint
3999 and then Lbit /= No_Uint
4003 ("position cannot be negative", Position (CC));
4007 ("first bit cannot be negative", First_Bit (CC));
4009 -- The Last_Bit specified in a component clause must not be
4010 -- less than the First_Bit minus one (RM-13.5.1(10)).
4012 elsif Lbit < Fbit - 1 then
4014 ("last bit cannot be less than first bit minus one",
4017 -- Values look OK, so find the corresponding record component
4018 -- Even though the syntax allows an attribute reference for
4019 -- implementation-defined components, GNAT does not allow the
4020 -- tag to get an explicit position.
4022 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
4023 if Attribute_Name (Component_Name (CC)) = Name_Tag then
4024 Error_Msg_N ("position of tag cannot be specified", CC);
4026 Error_Msg_N ("illegal component name", CC);
4030 Comp := First_Entity (Rectype);
4031 while Present (Comp) loop
4032 exit when Chars (Comp) = Chars (Component_Name (CC));
4038 -- Maybe component of base type that is absent from
4039 -- statically constrained first subtype.
4041 Comp := First_Entity (Base_Type (Rectype));
4042 while Present (Comp) loop
4043 exit when Chars (Comp) = Chars (Component_Name (CC));
4050 ("component clause is for non-existent field", CC);
4052 -- Ada 2012 (AI05-0026): Any name that denotes a
4053 -- discriminant of an object of an unchecked union type
4054 -- shall not occur within a record_representation_clause.
4056 -- The general restriction of using record rep clauses on
4057 -- Unchecked_Union types has now been lifted. Since it is
4058 -- possible to introduce a record rep clause which mentions
4059 -- the discriminant of an Unchecked_Union in non-Ada 2012
4060 -- code, this check is applied to all versions of the
4063 elsif Ekind (Comp) = E_Discriminant
4064 and then Is_Unchecked_Union (Rectype)
4067 ("cannot reference discriminant of Unchecked_Union",
4068 Component_Name (CC));
4070 elsif Present (Component_Clause (Comp)) then
4072 -- Diagnose duplicate rep clause, or check consistency
4073 -- if this is an inherited component. In a double fault,
4074 -- there may be a duplicate inconsistent clause for an
4075 -- inherited component.
4077 if Scope (Original_Record_Component (Comp)) = Rectype
4078 or else Parent (Component_Clause (Comp)) = N
4080 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
4081 Error_Msg_N ("component clause previously given#", CC);
4085 Rep1 : constant Node_Id := Component_Clause (Comp);
4087 if Intval (Position (Rep1)) /=
4088 Intval (Position (CC))
4089 or else Intval (First_Bit (Rep1)) /=
4090 Intval (First_Bit (CC))
4091 or else Intval (Last_Bit (Rep1)) /=
4092 Intval (Last_Bit (CC))
4094 Error_Msg_N ("component clause inconsistent "
4095 & "with representation of ancestor", CC);
4096 elsif Warn_On_Redundant_Constructs then
4097 Error_Msg_N ("?redundant component clause "
4098 & "for inherited component!", CC);
4103 -- Normal case where this is the first component clause we
4104 -- have seen for this entity, so set it up properly.
4107 -- Make reference for field in record rep clause and set
4108 -- appropriate entity field in the field identifier.
4111 (Comp, Component_Name (CC), Set_Ref => False);
4112 Set_Entity (Component_Name (CC), Comp);
4114 -- Update Fbit and Lbit to the actual bit number
4116 Fbit := Fbit + UI_From_Int (SSU) * Posit;
4117 Lbit := Lbit + UI_From_Int (SSU) * Posit;
4119 if Has_Size_Clause (Rectype)
4120 and then RM_Size (Rectype) <= Lbit
4123 ("bit number out of range of specified size",
4126 Set_Component_Clause (Comp, CC);
4127 Set_Component_Bit_Offset (Comp, Fbit);
4128 Set_Esize (Comp, 1 + (Lbit - Fbit));
4129 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
4130 Set_Normalized_Position (Comp, Fbit / SSU);
4132 if Warn_On_Overridden_Size
4133 and then Has_Size_Clause (Etype (Comp))
4134 and then RM_Size (Etype (Comp)) /= Esize (Comp)
4137 ("?component size overrides size clause for&",
4138 Component_Name (CC), Etype (Comp));
4141 -- This information is also set in the corresponding
4142 -- component of the base type, found by accessing the
4143 -- Original_Record_Component link if it is present.
4145 Ocomp := Original_Record_Component (Comp);
4152 (Component_Name (CC),
4158 (Comp, First_Node (CC), "component clause", Biased);
4160 if Present (Ocomp) then
4161 Set_Component_Clause (Ocomp, CC);
4162 Set_Component_Bit_Offset (Ocomp, Fbit);
4163 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
4164 Set_Normalized_Position (Ocomp, Fbit / SSU);
4165 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
4167 Set_Normalized_Position_Max
4168 (Ocomp, Normalized_Position (Ocomp));
4170 -- Note: we don't use Set_Biased here, because we
4171 -- already gave a warning above if needed, and we
4172 -- would get a duplicate for the same name here.
4174 Set_Has_Biased_Representation
4175 (Ocomp, Has_Biased_Representation (Comp));
4178 if Esize (Comp) < 0 then
4179 Error_Msg_N ("component size is negative", CC);
4190 -- Check missing components if Complete_Representation pragma appeared
4192 if Present (CR_Pragma) then
4193 Comp := First_Component_Or_Discriminant (Rectype);
4194 while Present (Comp) loop
4195 if No (Component_Clause (Comp)) then
4197 ("missing component clause for &", CR_Pragma, Comp);
4200 Next_Component_Or_Discriminant (Comp);
4203 -- If no Complete_Representation pragma, warn if missing components
4205 elsif Warn_On_Unrepped_Components then
4207 Num_Repped_Components : Nat := 0;
4208 Num_Unrepped_Components : Nat := 0;
4211 -- First count number of repped and unrepped components
4213 Comp := First_Component_Or_Discriminant (Rectype);
4214 while Present (Comp) loop
4215 if Present (Component_Clause (Comp)) then
4216 Num_Repped_Components := Num_Repped_Components + 1;
4218 Num_Unrepped_Components := Num_Unrepped_Components + 1;
4221 Next_Component_Or_Discriminant (Comp);
4224 -- We are only interested in the case where there is at least one
4225 -- unrepped component, and at least half the components have rep
4226 -- clauses. We figure that if less than half have them, then the
4227 -- partial rep clause is really intentional. If the component
4228 -- type has no underlying type set at this point (as for a generic
4229 -- formal type), we don't know enough to give a warning on the
4232 if Num_Unrepped_Components > 0
4233 and then Num_Unrepped_Components < Num_Repped_Components
4235 Comp := First_Component_Or_Discriminant (Rectype);
4236 while Present (Comp) loop
4237 if No (Component_Clause (Comp))
4238 and then Comes_From_Source (Comp)
4239 and then Present (Underlying_Type (Etype (Comp)))
4240 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
4241 or else Size_Known_At_Compile_Time
4242 (Underlying_Type (Etype (Comp))))
4243 and then not Has_Warnings_Off (Rectype)
4245 Error_Msg_Sloc := Sloc (Comp);
4247 ("?no component clause given for & declared #",
4251 Next_Component_Or_Discriminant (Comp);
4256 end Analyze_Record_Representation_Clause;
4258 -------------------------------
4259 -- Build_Invariant_Procedure --
4260 -------------------------------
4262 -- The procedure that is constructed here has the form
4264 -- procedure typInvariant (Ixxx : typ) is
4266 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4267 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4269 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
4271 -- end typInvariant;
4273 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
4274 Loc : constant Source_Ptr := Sloc (Typ);
4281 Visible_Decls : constant List_Id := Visible_Declarations (N);
4282 Private_Decls : constant List_Id := Private_Declarations (N);
4284 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
4285 -- Appends statements to Stmts for any invariants in the rep item chain
4286 -- of the given type. If Inherit is False, then we only process entries
4287 -- on the chain for the type Typ. If Inherit is True, then we ignore any
4288 -- Invariant aspects, but we process all Invariant'Class aspects, adding
4289 -- "inherited" to the exception message and generating an informational
4290 -- message about the inheritance of an invariant.
4292 Object_Name : constant Name_Id := New_Internal_Name ('I');
4293 -- Name for argument of invariant procedure
4295 Object_Entity : constant Node_Id :=
4296 Make_Defining_Identifier (Loc, Object_Name);
4297 -- The procedure declaration entity for the argument
4299 --------------------
4300 -- Add_Invariants --
4301 --------------------
4303 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
4313 procedure Replace_Type_Reference (N : Node_Id);
4314 -- Replace a single occurrence N of the subtype name with a reference
4315 -- to the formal of the predicate function. N can be an identifier
4316 -- referencing the subtype, or a selected component, representing an
4317 -- appropriately qualified occurrence of the subtype name.
4319 procedure Replace_Type_References is
4320 new Replace_Type_References_Generic (Replace_Type_Reference);
4321 -- Traverse an expression replacing all occurrences of the subtype
4322 -- name with appropriate references to the object that is the formal
4323 -- parameter of the predicate function. Note that we must ensure
4324 -- that the type and entity information is properly set in the
4325 -- replacement node, since we will do a Preanalyze call of this
4326 -- expression without proper visibility of the procedure argument.
4328 ----------------------------
4329 -- Replace_Type_Reference --
4330 ----------------------------
4332 procedure Replace_Type_Reference (N : Node_Id) is
4334 -- Invariant'Class, replace with T'Class (obj)
4336 if Class_Present (Ritem) then
4338 Make_Type_Conversion (Loc,
4340 Make_Attribute_Reference (Loc,
4341 Prefix => New_Occurrence_Of (T, Loc),
4342 Attribute_Name => Name_Class),
4343 Expression => Make_Identifier (Loc, Object_Name)));
4345 Set_Entity (Expression (N), Object_Entity);
4346 Set_Etype (Expression (N), Typ);
4348 -- Invariant, replace with obj
4351 Rewrite (N, Make_Identifier (Loc, Object_Name));
4352 Set_Entity (N, Object_Entity);
4355 end Replace_Type_Reference;
4357 -- Start of processing for Add_Invariants
4360 Ritem := First_Rep_Item (T);
4361 while Present (Ritem) loop
4362 if Nkind (Ritem) = N_Pragma
4363 and then Pragma_Name (Ritem) = Name_Invariant
4365 Arg1 := First (Pragma_Argument_Associations (Ritem));
4366 Arg2 := Next (Arg1);
4367 Arg3 := Next (Arg2);
4369 Arg1 := Get_Pragma_Arg (Arg1);
4370 Arg2 := Get_Pragma_Arg (Arg2);
4372 -- For Inherit case, ignore Invariant, process only Class case
4375 if not Class_Present (Ritem) then
4379 -- For Inherit false, process only item for right type
4382 if Entity (Arg1) /= Typ then
4388 Stmts := Empty_List;
4391 Exp := New_Copy_Tree (Arg2);
4394 -- We need to replace any occurrences of the name of the type
4395 -- with references to the object, converted to type'Class in
4396 -- the case of Invariant'Class aspects.
4398 Replace_Type_References (Exp, Chars (T));
4400 -- If this invariant comes from an aspect, find the aspect
4401 -- specification, and replace the saved expression because
4402 -- we need the subtype references replaced for the calls to
4403 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4404 -- and Check_Aspect_At_End_Of_Declarations.
4406 if From_Aspect_Specification (Ritem) then
4411 -- Loop to find corresponding aspect, note that this
4412 -- must be present given the pragma is marked delayed.
4414 Aitem := Next_Rep_Item (Ritem);
4415 while Present (Aitem) loop
4416 if Nkind (Aitem) = N_Aspect_Specification
4417 and then Aspect_Rep_Item (Aitem) = Ritem
4420 (Identifier (Aitem), New_Copy_Tree (Exp));
4424 Aitem := Next_Rep_Item (Aitem);
4429 -- Now we need to preanalyze the expression to properly capture
4430 -- the visibility in the visible part. The expression will not
4431 -- be analyzed for real until the body is analyzed, but that is
4432 -- at the end of the private part and has the wrong visibility.
4434 Set_Parent (Exp, N);
4435 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
4437 -- Build first two arguments for Check pragma
4440 Make_Pragma_Argument_Association (Loc,
4441 Expression => Make_Identifier (Loc, Name_Invariant)),
4442 Make_Pragma_Argument_Association (Loc, Expression => Exp));
4444 -- Add message if present in Invariant pragma
4446 if Present (Arg3) then
4447 Str := Strval (Get_Pragma_Arg (Arg3));
4449 -- If inherited case, and message starts "failed invariant",
4450 -- change it to be "failed inherited invariant".
4453 String_To_Name_Buffer (Str);
4455 if Name_Buffer (1 .. 16) = "failed invariant" then
4456 Insert_Str_In_Name_Buffer ("inherited ", 8);
4457 Str := String_From_Name_Buffer;
4462 Make_Pragma_Argument_Association (Loc,
4463 Expression => Make_String_Literal (Loc, Str)));
4466 -- Add Check pragma to list of statements
4470 Pragma_Identifier =>
4471 Make_Identifier (Loc, Name_Check),
4472 Pragma_Argument_Associations => Assoc));
4474 -- If Inherited case and option enabled, output info msg. Note
4475 -- that we know this is a case of Invariant'Class.
4477 if Inherit and Opt.List_Inherited_Aspects then
4478 Error_Msg_Sloc := Sloc (Ritem);
4480 ("?info: & inherits `Invariant''Class` aspect from #",
4486 Next_Rep_Item (Ritem);
4490 -- Start of processing for Build_Invariant_Procedure
4496 Set_Etype (Object_Entity, Typ);
4498 -- Add invariants for the current type
4500 Add_Invariants (Typ, Inherit => False);
4502 -- Add invariants for parent types
4505 Current_Typ : Entity_Id;
4506 Parent_Typ : Entity_Id;
4511 Parent_Typ := Etype (Current_Typ);
4513 if Is_Private_Type (Parent_Typ)
4514 and then Present (Full_View (Base_Type (Parent_Typ)))
4516 Parent_Typ := Full_View (Base_Type (Parent_Typ));
4519 exit when Parent_Typ = Current_Typ;
4521 Current_Typ := Parent_Typ;
4522 Add_Invariants (Current_Typ, Inherit => True);
4526 -- Build the procedure if we generated at least one Check pragma
4528 if Stmts /= No_List then
4530 -- Build procedure declaration
4533 Make_Defining_Identifier (Loc,
4534 Chars => New_External_Name (Chars (Typ), "Invariant"));
4535 Set_Has_Invariants (SId);
4536 Set_Invariant_Procedure (Typ, SId);
4539 Make_Procedure_Specification (Loc,
4540 Defining_Unit_Name => SId,
4541 Parameter_Specifications => New_List (
4542 Make_Parameter_Specification (Loc,
4543 Defining_Identifier => Object_Entity,
4544 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4546 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4548 -- Build procedure body
4551 Make_Defining_Identifier (Loc,
4552 Chars => New_External_Name (Chars (Typ), "Invariant"));
4555 Make_Procedure_Specification (Loc,
4556 Defining_Unit_Name => SId,
4557 Parameter_Specifications => New_List (
4558 Make_Parameter_Specification (Loc,
4559 Defining_Identifier =>
4560 Make_Defining_Identifier (Loc, Object_Name),
4561 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4564 Make_Subprogram_Body (Loc,
4565 Specification => Spec,
4566 Declarations => Empty_List,
4567 Handled_Statement_Sequence =>
4568 Make_Handled_Sequence_Of_Statements (Loc,
4569 Statements => Stmts));
4571 -- Insert procedure declaration and spec at the appropriate points.
4572 -- Skip this if there are no private declarations (that's an error
4573 -- that will be diagnosed elsewhere, and there is no point in having
4574 -- an invariant procedure set if the full declaration is missing).
4576 if Present (Private_Decls) then
4578 -- The spec goes at the end of visible declarations, but they have
4579 -- already been analyzed, so we need to explicitly do the analyze.
4581 Append_To (Visible_Decls, PDecl);
4584 -- The body goes at the end of the private declarations, which we
4585 -- have not analyzed yet, so we do not need to perform an explicit
4586 -- analyze call. We skip this if there are no private declarations
4587 -- (this is an error that will be caught elsewhere);
4589 Append_To (Private_Decls, PBody);
4592 end Build_Invariant_Procedure;
4594 ------------------------------
4595 -- Build_Predicate_Function --
4596 ------------------------------
4598 -- The procedure that is constructed here has the form
4600 -- function typPredicate (Ixxx : typ) return Boolean is
4603 -- exp1 and then exp2 and then ...
4604 -- and then typ1Predicate (typ1 (Ixxx))
4605 -- and then typ2Predicate (typ2 (Ixxx))
4607 -- end typPredicate;
4609 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4610 -- this is the point at which these expressions get analyzed, providing the
4611 -- required delay, and typ1, typ2, are entities from which predicates are
4612 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4613 -- use this function even if checks are off, e.g. for membership tests.
4615 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4616 Loc : constant Source_Ptr := Sloc (Typ);
4623 -- This is the expression for the return statement in the function. It
4624 -- is build by connecting the component predicates with AND THEN.
4626 procedure Add_Call (T : Entity_Id);
4627 -- Includes a call to the predicate function for type T in Expr if T
4628 -- has predicates and Predicate_Function (T) is non-empty.
4630 procedure Add_Predicates;
4631 -- Appends expressions for any Predicate pragmas in the rep item chain
4632 -- Typ to Expr. Note that we look only at items for this exact entity.
4633 -- Inheritance of predicates for the parent type is done by calling the
4634 -- Predicate_Function of the parent type, using Add_Call above.
4636 Object_Name : constant Name_Id := New_Internal_Name ('I');
4637 -- Name for argument of Predicate procedure
4639 Object_Entity : constant Entity_Id :=
4640 Make_Defining_Identifier (Loc, Object_Name);
4641 -- The entity for the spec entity for the argument
4643 Dynamic_Predicate_Present : Boolean := False;
4644 -- Set True if a dynamic predicate is present, results in the entire
4645 -- predicate being considered dynamic even if it looks static
4647 Static_Predicate_Present : Node_Id := Empty;
4648 -- Set to N_Pragma node for a static predicate if one is encountered.
4654 procedure Add_Call (T : Entity_Id) is
4658 if Present (T) and then Present (Predicate_Function (T)) then
4659 Set_Has_Predicates (Typ);
4661 -- Build the call to the predicate function of T
4665 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4667 -- Add call to evolving expression, using AND THEN if needed
4674 Left_Opnd => Relocate_Node (Expr),
4678 -- Output info message on inheritance if required. Note we do not
4679 -- give this information for generic actual types, since it is
4680 -- unwelcome noise in that case in instantiations. We also
4681 -- generally suppress the message in instantiations, and also
4682 -- if it involves internal names.
4684 if Opt.List_Inherited_Aspects
4685 and then not Is_Generic_Actual_Type (Typ)
4686 and then Instantiation_Depth (Sloc (Typ)) = 0
4687 and then not Is_Internal_Name (Chars (T))
4688 and then not Is_Internal_Name (Chars (Typ))
4690 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4691 Error_Msg_Node_2 := T;
4692 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4697 --------------------
4698 -- Add_Predicates --
4699 --------------------
4701 procedure Add_Predicates is
4706 procedure Replace_Type_Reference (N : Node_Id);
4707 -- Replace a single occurrence N of the subtype name with a reference
4708 -- to the formal of the predicate function. N can be an identifier
4709 -- referencing the subtype, or a selected component, representing an
4710 -- appropriately qualified occurrence of the subtype name.
4712 procedure Replace_Type_References is
4713 new Replace_Type_References_Generic (Replace_Type_Reference);
4714 -- Traverse an expression changing every occurrence of an identifier
4715 -- whose name matches the name of the subtype with a reference to
4716 -- the formal parameter of the predicate function.
4718 ----------------------------
4719 -- Replace_Type_Reference --
4720 ----------------------------
4722 procedure Replace_Type_Reference (N : Node_Id) is
4724 Rewrite (N, Make_Identifier (Loc, Object_Name));
4725 Set_Entity (N, Object_Entity);
4727 end Replace_Type_Reference;
4729 -- Start of processing for Add_Predicates
4732 Ritem := First_Rep_Item (Typ);
4733 while Present (Ritem) loop
4734 if Nkind (Ritem) = N_Pragma
4735 and then Pragma_Name (Ritem) = Name_Predicate
4737 if From_Dynamic_Predicate (Ritem) then
4738 Dynamic_Predicate_Present := True;
4739 elsif From_Static_Predicate (Ritem) then
4740 Static_Predicate_Present := Ritem;
4743 -- Acquire arguments
4745 Arg1 := First (Pragma_Argument_Associations (Ritem));
4746 Arg2 := Next (Arg1);
4748 Arg1 := Get_Pragma_Arg (Arg1);
4749 Arg2 := Get_Pragma_Arg (Arg2);
4751 -- See if this predicate pragma is for the current type or for
4752 -- its full view. A predicate on a private completion is placed
4753 -- on the partial view beause this is the visible entity that
4756 if Entity (Arg1) = Typ
4757 or else Full_View (Entity (Arg1)) = Typ
4760 -- We have a match, this entry is for our subtype
4762 -- We need to replace any occurrences of the name of the
4763 -- type with references to the object.
4765 Replace_Type_References (Arg2, Chars (Typ));
4767 -- If this predicate comes from an aspect, find the aspect
4768 -- specification, and replace the saved expression because
4769 -- we need the subtype references replaced for the calls to
4770 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4771 -- and Check_Aspect_At_End_Of_Declarations.
4773 if From_Aspect_Specification (Ritem) then
4778 -- Loop to find corresponding aspect, note that this
4779 -- must be present given the pragma is marked delayed.
4781 Aitem := Next_Rep_Item (Ritem);
4783 if Nkind (Aitem) = N_Aspect_Specification
4784 and then Aspect_Rep_Item (Aitem) = Ritem
4787 (Identifier (Aitem), New_Copy_Tree (Arg2));
4791 Aitem := Next_Rep_Item (Aitem);
4796 -- Now we can add the expression
4799 Expr := Relocate_Node (Arg2);
4801 -- There already was a predicate, so add to it
4806 Left_Opnd => Relocate_Node (Expr),
4807 Right_Opnd => Relocate_Node (Arg2));
4812 Next_Rep_Item (Ritem);
4816 -- Start of processing for Build_Predicate_Function
4819 -- Initialize for construction of statement list
4823 -- Return if already built or if type does not have predicates
4825 if not Has_Predicates (Typ)
4826 or else Present (Predicate_Function (Typ))
4831 -- Add Predicates for the current type
4835 -- Add predicates for ancestor if present
4838 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4840 if Present (Atyp) then
4845 -- If we have predicates, build the function
4847 if Present (Expr) then
4849 -- Build function declaration
4851 pragma Assert (Has_Predicates (Typ));
4853 Make_Defining_Identifier (Loc,
4854 Chars => New_External_Name (Chars (Typ), "Predicate"));
4855 Set_Has_Predicates (SId);
4856 Set_Predicate_Function (Typ, SId);
4859 Make_Function_Specification (Loc,
4860 Defining_Unit_Name => SId,
4861 Parameter_Specifications => New_List (
4862 Make_Parameter_Specification (Loc,
4863 Defining_Identifier => Object_Entity,
4864 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4865 Result_Definition =>
4866 New_Occurrence_Of (Standard_Boolean, Loc));
4868 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4870 -- Build function body
4873 Make_Defining_Identifier (Loc,
4874 Chars => New_External_Name (Chars (Typ), "Predicate"));
4877 Make_Function_Specification (Loc,
4878 Defining_Unit_Name => SId,
4879 Parameter_Specifications => New_List (
4880 Make_Parameter_Specification (Loc,
4881 Defining_Identifier =>
4882 Make_Defining_Identifier (Loc, Object_Name),
4884 New_Occurrence_Of (Typ, Loc))),
4885 Result_Definition =>
4886 New_Occurrence_Of (Standard_Boolean, Loc));
4889 Make_Subprogram_Body (Loc,
4890 Specification => Spec,
4891 Declarations => Empty_List,
4892 Handled_Statement_Sequence =>
4893 Make_Handled_Sequence_Of_Statements (Loc,
4894 Statements => New_List (
4895 Make_Simple_Return_Statement (Loc,
4896 Expression => Expr))));
4898 -- Insert declaration before freeze node and body after
4900 Insert_Before_And_Analyze (N, FDecl);
4901 Insert_After_And_Analyze (N, FBody);
4903 -- Deal with static predicate case
4905 if Ekind_In (Typ, E_Enumeration_Subtype,
4906 E_Modular_Integer_Subtype,
4907 E_Signed_Integer_Subtype)
4908 and then Is_Static_Subtype (Typ)
4909 and then not Dynamic_Predicate_Present
4911 Build_Static_Predicate (Typ, Expr, Object_Name);
4913 if Present (Static_Predicate_Present)
4914 and No (Static_Predicate (Typ))
4917 ("expression does not have required form for "
4918 & "static predicate",
4919 Next (First (Pragma_Argument_Associations
4920 (Static_Predicate_Present))));
4924 end Build_Predicate_Function;
4926 ----------------------------
4927 -- Build_Static_Predicate --
4928 ----------------------------
4930 procedure Build_Static_Predicate
4935 Loc : constant Source_Ptr := Sloc (Expr);
4937 Non_Static : exception;
4938 -- Raised if something non-static is found
4940 Btyp : constant Entity_Id := Base_Type (Typ);
4942 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4943 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4944 -- Low bound and high bound value of base type of Typ
4946 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4947 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4948 -- Low bound and high bound values of static subtype Typ
4953 -- One entry in a Rlist value, a single REnt (range entry) value
4954 -- denotes one range from Lo to Hi. To represent a single value
4955 -- range Lo = Hi = value.
4957 type RList is array (Nat range <>) of REnt;
4958 -- A list of ranges. The ranges are sorted in increasing order,
4959 -- and are disjoint (there is a gap of at least one value between
4960 -- each range in the table). A value is in the set of ranges in
4961 -- Rlist if it lies within one of these ranges
4963 False_Range : constant RList :=
4964 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4965 -- An empty set of ranges represents a range list that can never be
4966 -- satisfied, since there are no ranges in which the value could lie,
4967 -- so it does not lie in any of them. False_Range is a canonical value
4968 -- for this empty set, but general processing should test for an Rlist
4969 -- with length zero (see Is_False predicate), since other null ranges
4970 -- may appear which must be treated as False.
4972 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4973 -- Range representing True, value must be in the base range
4975 function "and" (Left, Right : RList) return RList;
4976 -- And's together two range lists, returning a range list. This is
4977 -- a set intersection operation.
4979 function "or" (Left, Right : RList) return RList;
4980 -- Or's together two range lists, returning a range list. This is a
4981 -- set union operation.
4983 function "not" (Right : RList) return RList;
4984 -- Returns complement of a given range list, i.e. a range list
4985 -- representing all the values in TLo .. THi that are not in the
4986 -- input operand Right.
4988 function Build_Val (V : Uint) return Node_Id;
4989 -- Return an analyzed N_Identifier node referencing this value, suitable
4990 -- for use as an entry in the Static_Predicate list. This node is typed
4991 -- with the base type.
4993 function Build_Range (Lo, Hi : Uint) return Node_Id;
4994 -- Return an analyzed N_Range node referencing this range, suitable
4995 -- for use as an entry in the Static_Predicate list. This node is typed
4996 -- with the base type.
4998 function Get_RList (Exp : Node_Id) return RList;
4999 -- This is a recursive routine that converts the given expression into
5000 -- a list of ranges, suitable for use in building the static predicate.
5002 function Is_False (R : RList) return Boolean;
5003 pragma Inline (Is_False);
5004 -- Returns True if the given range list is empty, and thus represents
5005 -- a False list of ranges that can never be satisfied.
5007 function Is_True (R : RList) return Boolean;
5008 -- Returns True if R trivially represents the True predicate by having
5009 -- a single range from BLo to BHi.
5011 function Is_Type_Ref (N : Node_Id) return Boolean;
5012 pragma Inline (Is_Type_Ref);
5013 -- Returns if True if N is a reference to the type for the predicate in
5014 -- the expression (i.e. if it is an identifier whose Chars field matches
5015 -- the Nam given in the call).
5017 function Lo_Val (N : Node_Id) return Uint;
5018 -- Given static expression or static range from a Static_Predicate list,
5019 -- gets expression value or low bound of range.
5021 function Hi_Val (N : Node_Id) return Uint;
5022 -- Given static expression or static range from a Static_Predicate list,
5023 -- gets expression value of high bound of range.
5025 function Membership_Entry (N : Node_Id) return RList;
5026 -- Given a single membership entry (range, value, or subtype), returns
5027 -- the corresponding range list. Raises Static_Error if not static.
5029 function Membership_Entries (N : Node_Id) return RList;
5030 -- Given an element on an alternatives list of a membership operation,
5031 -- returns the range list corresponding to this entry and all following
5032 -- entries (i.e. returns the "or" of this list of values).
5034 function Stat_Pred (Typ : Entity_Id) return RList;
5035 -- Given a type, if it has a static predicate, then return the predicate
5036 -- as a range list, otherwise raise Non_Static.
5042 function "and" (Left, Right : RList) return RList is
5044 -- First range of result
5046 SLeft : Nat := Left'First;
5047 -- Start of rest of left entries
5049 SRight : Nat := Right'First;
5050 -- Start of rest of right entries
5053 -- If either range is True, return the other
5055 if Is_True (Left) then
5057 elsif Is_True (Right) then
5061 -- If either range is False, return False
5063 if Is_False (Left) or else Is_False (Right) then
5067 -- Loop to remove entries at start that are disjoint, and thus
5068 -- just get discarded from the result entirely.
5071 -- If no operands left in either operand, result is false
5073 if SLeft > Left'Last or else SRight > Right'Last then
5076 -- Discard first left operand entry if disjoint with right
5078 elsif Left (SLeft).Hi < Right (SRight).Lo then
5081 -- Discard first right operand entry if disjoint with left
5083 elsif Right (SRight).Hi < Left (SLeft).Lo then
5084 SRight := SRight + 1;
5086 -- Otherwise we have an overlapping entry
5093 -- Now we have two non-null operands, and first entries overlap.
5094 -- The first entry in the result will be the overlapping part of
5095 -- these two entries.
5097 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
5098 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
5100 -- Now we can remove the entry that ended at a lower value, since
5101 -- its contribution is entirely contained in Fent.
5103 if Left (SLeft).Hi <= Right (SRight).Hi then
5106 SRight := SRight + 1;
5109 -- Compute result by concatenating this first entry with the "and"
5110 -- of the remaining parts of the left and right operands. Note that
5111 -- if either of these is empty, "and" will yield empty, so that we
5112 -- will end up with just Fent, which is what we want in that case.
5115 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
5122 function "not" (Right : RList) return RList is
5124 -- Return True if False range
5126 if Is_False (Right) then
5130 -- Return False if True range
5132 if Is_True (Right) then
5136 -- Here if not trivial case
5139 Result : RList (1 .. Right'Length + 1);
5140 -- May need one more entry for gap at beginning and end
5143 -- Number of entries stored in Result
5148 if Right (Right'First).Lo > TLo then
5150 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
5153 -- Gaps between ranges
5155 for J in Right'First .. Right'Last - 1 loop
5158 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
5163 if Right (Right'Last).Hi < THi then
5165 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
5168 return Result (1 .. Count);
5176 function "or" (Left, Right : RList) return RList is
5178 -- First range of result
5180 SLeft : Nat := Left'First;
5181 -- Start of rest of left entries
5183 SRight : Nat := Right'First;
5184 -- Start of rest of right entries
5187 -- If either range is True, return True
5189 if Is_True (Left) or else Is_True (Right) then
5193 -- If either range is False (empty), return the other
5195 if Is_False (Left) then
5197 elsif Is_False (Right) then
5201 -- Initialize result first entry from left or right operand
5202 -- depending on which starts with the lower range.
5204 if Left (SLeft).Lo < Right (SRight).Lo then
5205 FEnt := Left (SLeft);
5208 FEnt := Right (SRight);
5209 SRight := SRight + 1;
5212 -- This loop eats ranges from left and right operands that
5213 -- are contiguous with the first range we are gathering.
5216 -- Eat first entry in left operand if contiguous or
5217 -- overlapped by gathered first operand of result.
5219 if SLeft <= Left'Last
5220 and then Left (SLeft).Lo <= FEnt.Hi + 1
5222 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
5225 -- Eat first entry in right operand if contiguous or
5226 -- overlapped by gathered right operand of result.
5228 elsif SRight <= Right'Last
5229 and then Right (SRight).Lo <= FEnt.Hi + 1
5231 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
5232 SRight := SRight + 1;
5234 -- All done if no more entries to eat!
5241 -- Obtain result as the first entry we just computed, concatenated
5242 -- to the "or" of the remaining results (if one operand is empty,
5243 -- this will just concatenate with the other
5246 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
5253 function Build_Range (Lo, Hi : Uint) return Node_Id is
5257 return Build_Val (Hi);
5261 Low_Bound => Build_Val (Lo),
5262 High_Bound => Build_Val (Hi));
5263 Set_Etype (Result, Btyp);
5264 Set_Analyzed (Result);
5273 function Build_Val (V : Uint) return Node_Id is
5277 if Is_Enumeration_Type (Typ) then
5278 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
5280 Result := Make_Integer_Literal (Loc, V);
5283 Set_Etype (Result, Btyp);
5284 Set_Is_Static_Expression (Result);
5285 Set_Analyzed (Result);
5293 function Get_RList (Exp : Node_Id) return RList is
5298 -- Static expression can only be true or false
5300 if Is_OK_Static_Expression (Exp) then
5304 if Expr_Value (Exp) = 0 then
5311 -- Otherwise test node type
5319 when N_Op_And | N_And_Then =>
5320 return Get_RList (Left_Opnd (Exp))
5322 Get_RList (Right_Opnd (Exp));
5326 when N_Op_Or | N_Or_Else =>
5327 return Get_RList (Left_Opnd (Exp))
5329 Get_RList (Right_Opnd (Exp));
5334 return not Get_RList (Right_Opnd (Exp));
5336 -- Comparisons of type with static value
5338 when N_Op_Compare =>
5339 -- Type is left operand
5341 if Is_Type_Ref (Left_Opnd (Exp))
5342 and then Is_OK_Static_Expression (Right_Opnd (Exp))
5344 Val := Expr_Value (Right_Opnd (Exp));
5346 -- Typ is right operand
5348 elsif Is_Type_Ref (Right_Opnd (Exp))
5349 and then Is_OK_Static_Expression (Left_Opnd (Exp))
5351 Val := Expr_Value (Left_Opnd (Exp));
5353 -- Invert sense of comparison
5356 when N_Op_Gt => Op := N_Op_Lt;
5357 when N_Op_Lt => Op := N_Op_Gt;
5358 when N_Op_Ge => Op := N_Op_Le;
5359 when N_Op_Le => Op := N_Op_Ge;
5360 when others => null;
5363 -- Other cases are non-static
5369 -- Construct range according to comparison operation
5373 return RList'(1 => REnt'(Val, Val));
5376 return RList'(1 => REnt'(Val, BHi));
5379 return RList'(1 => REnt'(Val + 1, BHi));
5382 return RList'(1 => REnt'(BLo, Val));
5385 return RList'(1 => REnt'(BLo, Val - 1));
5388 return RList'(REnt'(BLo, Val - 1),
5389 REnt'(Val + 1, BHi));
5392 raise Program_Error;
5398 if not Is_Type_Ref (Left_Opnd (Exp)) then
5402 if Present (Right_Opnd (Exp)) then
5403 return Membership_Entry (Right_Opnd (Exp));
5405 return Membership_Entries (First (Alternatives (Exp)));
5408 -- Negative membership (NOT IN)
5411 if not Is_Type_Ref (Left_Opnd (Exp)) then
5415 if Present (Right_Opnd (Exp)) then
5416 return not Membership_Entry (Right_Opnd (Exp));
5418 return not Membership_Entries (First (Alternatives (Exp)));
5421 -- Function call, may be call to static predicate
5423 when N_Function_Call =>
5424 if Is_Entity_Name (Name (Exp)) then
5426 Ent : constant Entity_Id := Entity (Name (Exp));
5428 if Has_Predicates (Ent) then
5429 return Stat_Pred (Etype (First_Formal (Ent)));
5434 -- Other function call cases are non-static
5438 -- Qualified expression, dig out the expression
5440 when N_Qualified_Expression =>
5441 return Get_RList (Expression (Exp));
5446 return (Get_RList (Left_Opnd (Exp))
5447 and not Get_RList (Right_Opnd (Exp)))
5448 or (Get_RList (Right_Opnd (Exp))
5449 and not Get_RList (Left_Opnd (Exp)));
5451 -- Any other node type is non-static
5462 function Hi_Val (N : Node_Id) return Uint is
5464 if Is_Static_Expression (N) then
5465 return Expr_Value (N);
5467 pragma Assert (Nkind (N) = N_Range);
5468 return Expr_Value (High_Bound (N));
5476 function Is_False (R : RList) return Boolean is
5478 return R'Length = 0;
5485 function Is_True (R : RList) return Boolean is
5488 and then R (R'First).Lo = BLo
5489 and then R (R'First).Hi = BHi;
5496 function Is_Type_Ref (N : Node_Id) return Boolean is
5498 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
5505 function Lo_Val (N : Node_Id) return Uint is
5507 if Is_Static_Expression (N) then
5508 return Expr_Value (N);
5510 pragma Assert (Nkind (N) = N_Range);
5511 return Expr_Value (Low_Bound (N));
5515 ------------------------
5516 -- Membership_Entries --
5517 ------------------------
5519 function Membership_Entries (N : Node_Id) return RList is
5521 if No (Next (N)) then
5522 return Membership_Entry (N);
5524 return Membership_Entry (N) or Membership_Entries (Next (N));
5526 end Membership_Entries;
5528 ----------------------
5529 -- Membership_Entry --
5530 ----------------------
5532 function Membership_Entry (N : Node_Id) return RList is
5540 if Nkind (N) = N_Range then
5541 if not Is_Static_Expression (Low_Bound (N))
5543 not Is_Static_Expression (High_Bound (N))
5547 SLo := Expr_Value (Low_Bound (N));
5548 SHi := Expr_Value (High_Bound (N));
5549 return RList'(1 => REnt'(SLo, SHi));
5552 -- Static expression case
5554 elsif Is_Static_Expression (N) then
5555 Val := Expr_Value (N);
5556 return RList'(1 => REnt'(Val, Val));
5558 -- Identifier (other than static expression) case
5560 else pragma Assert (Nkind (N) = N_Identifier);
5564 if Is_Type (Entity (N)) then
5566 -- If type has predicates, process them
5568 if Has_Predicates (Entity (N)) then
5569 return Stat_Pred (Entity (N));
5571 -- For static subtype without predicates, get range
5573 elsif Is_Static_Subtype (Entity (N)) then
5574 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
5575 SHi := Expr_Value (Type_High_Bound (Entity (N)));
5576 return RList'(1 => REnt'(SLo, SHi));
5578 -- Any other type makes us non-static
5584 -- Any other kind of identifier in predicate (e.g. a non-static
5585 -- expression value) means this is not a static predicate.
5591 end Membership_Entry;
5597 function Stat_Pred (Typ : Entity_Id) return RList is
5599 -- Not static if type does not have static predicates
5601 if not Has_Predicates (Typ)
5602 or else No (Static_Predicate (Typ))
5607 -- Otherwise we convert the predicate list to a range list
5610 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5614 P := First (Static_Predicate (Typ));
5615 for J in Result'Range loop
5616 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5624 -- Start of processing for Build_Static_Predicate
5627 -- Now analyze the expression to see if it is a static predicate
5630 Ranges : constant RList := Get_RList (Expr);
5631 -- Range list from expression if it is static
5636 -- Convert range list into a form for the static predicate. In the
5637 -- Ranges array, we just have raw ranges, these must be converted
5638 -- to properly typed and analyzed static expressions or range nodes.
5640 -- Note: here we limit ranges to the ranges of the subtype, so that
5641 -- a predicate is always false for values outside the subtype. That
5642 -- seems fine, such values are invalid anyway, and considering them
5643 -- to fail the predicate seems allowed and friendly, and furthermore
5644 -- simplifies processing for case statements and loops.
5648 for J in Ranges'Range loop
5650 Lo : Uint := Ranges (J).Lo;
5651 Hi : Uint := Ranges (J).Hi;
5654 -- Ignore completely out of range entry
5656 if Hi < TLo or else Lo > THi then
5659 -- Otherwise process entry
5662 -- Adjust out of range value to subtype range
5672 -- Convert range into required form
5675 Append_To (Plist, Build_Val (Lo));
5677 Append_To (Plist, Build_Range (Lo, Hi));
5683 -- Processing was successful and all entries were static, so now we
5684 -- can store the result as the predicate list.
5686 Set_Static_Predicate (Typ, Plist);
5688 -- The processing for static predicates put the expression into
5689 -- canonical form as a series of ranges. It also eliminated
5690 -- duplicates and collapsed and combined ranges. We might as well
5691 -- replace the alternatives list of the right operand of the
5692 -- membership test with the static predicate list, which will
5693 -- usually be more efficient.
5696 New_Alts : constant List_Id := New_List;
5701 Old_Node := First (Plist);
5702 while Present (Old_Node) loop
5703 New_Node := New_Copy (Old_Node);
5705 if Nkind (New_Node) = N_Range then
5706 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5707 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5710 Append_To (New_Alts, New_Node);
5714 -- If empty list, replace by False
5716 if Is_Empty_List (New_Alts) then
5717 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5719 -- Else replace by set membership test
5724 Left_Opnd => Make_Identifier (Loc, Nam),
5725 Right_Opnd => Empty,
5726 Alternatives => New_Alts));
5728 -- Resolve new expression in function context
5730 Install_Formals (Predicate_Function (Typ));
5731 Push_Scope (Predicate_Function (Typ));
5732 Analyze_And_Resolve (Expr, Standard_Boolean);
5738 -- If non-static, return doing nothing
5743 end Build_Static_Predicate;
5745 -----------------------------------------
5746 -- Check_Aspect_At_End_Of_Declarations --
5747 -----------------------------------------
5749 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5750 Ent : constant Entity_Id := Entity (ASN);
5751 Ident : constant Node_Id := Identifier (ASN);
5753 Freeze_Expr : constant Node_Id := Expression (ASN);
5754 -- Expression from call to Check_Aspect_At_Freeze_Point
5756 End_Decl_Expr : constant Node_Id := Entity (Ident);
5757 -- Expression to be analyzed at end of declarations
5759 T : constant Entity_Id := Etype (Freeze_Expr);
5760 -- Type required for preanalyze call
5762 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5765 -- Set False if error
5767 -- On entry to this procedure, Entity (Ident) contains a copy of the
5768 -- original expression from the aspect, saved for this purpose, and
5769 -- but Expression (Ident) is a preanalyzed copy of the expression,
5770 -- preanalyzed just after the freeze point.
5773 -- Case of stream attributes, just have to compare entities
5775 if A_Id = Aspect_Input or else
5776 A_Id = Aspect_Output or else
5777 A_Id = Aspect_Read or else
5780 Analyze (End_Decl_Expr);
5781 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5783 elsif A_Id = Aspect_Variable_Indexing or else
5784 A_Id = Aspect_Constant_Indexing or else
5785 A_Id = Aspect_Default_Iterator or else
5786 A_Id = Aspect_Iterator_Element
5788 -- Make type unfrozen before analysis, to prevent spurious errors
5789 -- about late attributes.
5791 Set_Is_Frozen (Ent, False);
5792 Analyze (End_Decl_Expr);
5793 Analyze (Aspect_Rep_Item (ASN));
5794 Set_Is_Frozen (Ent, True);
5796 -- If the end of declarations comes before any other freeze
5797 -- point, the Freeze_Expr is not analyzed: no check needed.
5800 Analyzed (Freeze_Expr)
5801 and then not In_Instance
5802 and then Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5807 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5808 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5811 -- Output error message if error
5815 ("visibility of aspect for& changes after freeze point",
5818 ("?info: & is frozen here, aspects evaluated at this point",
5819 Freeze_Node (Ent), Ent);
5821 end Check_Aspect_At_End_Of_Declarations;
5823 ----------------------------------
5824 -- Check_Aspect_At_Freeze_Point --
5825 ----------------------------------
5827 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5828 Ident : constant Node_Id := Identifier (ASN);
5829 -- Identifier (use Entity field to save expression)
5832 -- Type required for preanalyze call
5834 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5837 -- On entry to this procedure, Entity (Ident) contains a copy of the
5838 -- original expression from the aspect, saved for this purpose.
5840 -- On exit from this procedure Entity (Ident) is unchanged, still
5841 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5842 -- of the expression, preanalyzed just after the freeze point.
5844 -- Make a copy of the expression to be preanalyed
5846 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5848 -- Find type for preanalyze call
5852 -- No_Aspect should be impossible
5855 raise Program_Error;
5857 -- Library unit aspects should be impossible (never delayed)
5859 when Library_Unit_Aspects =>
5860 raise Program_Error;
5862 -- Aspects taking an optional boolean argument. Should be impossible
5863 -- since these are never delayed.
5865 when Boolean_Aspects =>
5866 raise Program_Error;
5868 -- Test_Case aspect applies to entries and subprograms, hence should
5869 -- never be delayed.
5871 when Aspect_Test_Case =>
5872 raise Program_Error;
5874 when Aspect_Attach_Handler =>
5875 T := RTE (RE_Interrupt_ID);
5877 -- Default_Value is resolved with the type entity in question
5879 when Aspect_Default_Value =>
5882 -- Default_Component_Value is resolved with the component type
5884 when Aspect_Default_Component_Value =>
5885 T := Component_Type (Entity (ASN));
5887 -- Aspects corresponding to attribute definition clauses
5889 when Aspect_Address =>
5890 T := RTE (RE_Address);
5892 when Aspect_Bit_Order =>
5893 T := RTE (RE_Bit_Order);
5896 T := RTE (RE_CPU_Range);
5898 when Aspect_Dispatching_Domain =>
5899 T := RTE (RE_Dispatching_Domain);
5901 when Aspect_External_Tag =>
5902 T := Standard_String;
5904 when Aspect_Priority | Aspect_Interrupt_Priority =>
5905 T := Standard_Integer;
5907 when Aspect_Small =>
5908 T := Universal_Real;
5910 when Aspect_Storage_Pool =>
5911 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5913 when Aspect_Alignment |
5914 Aspect_Component_Size |
5915 Aspect_Machine_Radix |
5916 Aspect_Object_Size |
5918 Aspect_Storage_Size |
5919 Aspect_Stream_Size |
5920 Aspect_Value_Size =>
5923 -- Stream attribute. Special case, the expression is just an entity
5924 -- that does not need any resolution, so just analyze.
5930 Analyze (Expression (ASN));
5933 -- Same for Iterator aspects, where the expression is a function
5934 -- name. Legality rules are checked separately.
5936 when Aspect_Constant_Indexing |
5937 Aspect_Default_Iterator |
5938 Aspect_Iterator_Element |
5939 Aspect_Implicit_Dereference |
5940 Aspect_Variable_Indexing =>
5941 Analyze (Expression (ASN));
5944 -- Suppress/Unsuppress/Warnings should never be delayed
5946 when Aspect_Suppress |
5949 raise Program_Error;
5951 -- Pre/Post/Invariant/Predicate take boolean expressions
5953 when Aspect_Dynamic_Predicate |
5956 Aspect_Precondition |
5958 Aspect_Postcondition |
5960 Aspect_Static_Predicate |
5961 Aspect_Type_Invariant =>
5962 T := Standard_Boolean;
5965 -- Do the preanalyze call
5967 Preanalyze_Spec_Expression (Expression (ASN), T);
5968 end Check_Aspect_At_Freeze_Point;
5970 -----------------------------------
5971 -- Check_Constant_Address_Clause --
5972 -----------------------------------
5974 procedure Check_Constant_Address_Clause
5978 procedure Check_At_Constant_Address (Nod : Node_Id);
5979 -- Checks that the given node N represents a name whose 'Address is
5980 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5981 -- address value is the same at the point of declaration of U_Ent and at
5982 -- the time of elaboration of the address clause.
5984 procedure Check_Expr_Constants (Nod : Node_Id);
5985 -- Checks that Nod meets the requirements for a constant address clause
5986 -- in the sense of the enclosing procedure.
5988 procedure Check_List_Constants (Lst : List_Id);
5989 -- Check that all elements of list Lst meet the requirements for a
5990 -- constant address clause in the sense of the enclosing procedure.
5992 -------------------------------
5993 -- Check_At_Constant_Address --
5994 -------------------------------
5996 procedure Check_At_Constant_Address (Nod : Node_Id) is
5998 if Is_Entity_Name (Nod) then
5999 if Present (Address_Clause (Entity ((Nod)))) then
6001 ("invalid address clause for initialized object &!",
6004 ("address for& cannot" &
6005 " depend on another address clause! (RM 13.1(22))!",
6008 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
6009 and then Sloc (U_Ent) < Sloc (Entity (Nod))
6012 ("invalid address clause for initialized object &!",
6014 Error_Msg_Node_2 := U_Ent;
6016 ("\& must be defined before & (RM 13.1(22))!",
6020 elsif Nkind (Nod) = N_Selected_Component then
6022 T : constant Entity_Id := Etype (Prefix (Nod));
6025 if (Is_Record_Type (T)
6026 and then Has_Discriminants (T))
6029 and then Is_Record_Type (Designated_Type (T))
6030 and then Has_Discriminants (Designated_Type (T)))
6033 ("invalid address clause for initialized object &!",
6036 ("\address cannot depend on component" &
6037 " of discriminated record (RM 13.1(22))!",
6040 Check_At_Constant_Address (Prefix (Nod));
6044 elsif Nkind (Nod) = N_Indexed_Component then
6045 Check_At_Constant_Address (Prefix (Nod));
6046 Check_List_Constants (Expressions (Nod));
6049 Check_Expr_Constants (Nod);
6051 end Check_At_Constant_Address;
6053 --------------------------
6054 -- Check_Expr_Constants --
6055 --------------------------
6057 procedure Check_Expr_Constants (Nod : Node_Id) is
6058 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
6059 Ent : Entity_Id := Empty;
6062 if Nkind (Nod) in N_Has_Etype
6063 and then Etype (Nod) = Any_Type
6069 when N_Empty | N_Error =>
6072 when N_Identifier | N_Expanded_Name =>
6073 Ent := Entity (Nod);
6075 -- We need to look at the original node if it is different
6076 -- from the node, since we may have rewritten things and
6077 -- substituted an identifier representing the rewrite.
6079 if Original_Node (Nod) /= Nod then
6080 Check_Expr_Constants (Original_Node (Nod));
6082 -- If the node is an object declaration without initial
6083 -- value, some code has been expanded, and the expression
6084 -- is not constant, even if the constituents might be
6085 -- acceptable, as in A'Address + offset.
6087 if Ekind (Ent) = E_Variable
6089 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
6091 No (Expression (Declaration_Node (Ent)))
6094 ("invalid address clause for initialized object &!",
6097 -- If entity is constant, it may be the result of expanding
6098 -- a check. We must verify that its declaration appears
6099 -- before the object in question, else we also reject the
6102 elsif Ekind (Ent) = E_Constant
6103 and then In_Same_Source_Unit (Ent, U_Ent)
6104 and then Sloc (Ent) > Loc_U_Ent
6107 ("invalid address clause for initialized object &!",
6114 -- Otherwise look at the identifier and see if it is OK
6116 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
6117 or else Is_Type (Ent)
6122 Ekind (Ent) = E_Constant
6124 Ekind (Ent) = E_In_Parameter
6126 -- This is the case where we must have Ent defined before
6127 -- U_Ent. Clearly if they are in different units this
6128 -- requirement is met since the unit containing Ent is
6129 -- already processed.
6131 if not In_Same_Source_Unit (Ent, U_Ent) then
6134 -- Otherwise location of Ent must be before the location
6135 -- of U_Ent, that's what prior defined means.
6137 elsif Sloc (Ent) < Loc_U_Ent then
6142 ("invalid address clause for initialized object &!",
6144 Error_Msg_Node_2 := U_Ent;
6146 ("\& must be defined before & (RM 13.1(22))!",
6150 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
6151 Check_Expr_Constants (Original_Node (Nod));
6155 ("invalid address clause for initialized object &!",
6158 if Comes_From_Source (Ent) then
6160 ("\reference to variable& not allowed"
6161 & " (RM 13.1(22))!", Nod, Ent);
6164 ("non-static expression not allowed"
6165 & " (RM 13.1(22))!", Nod);
6169 when N_Integer_Literal =>
6171 -- If this is a rewritten unchecked conversion, in a system
6172 -- where Address is an integer type, always use the base type
6173 -- for a literal value. This is user-friendly and prevents
6174 -- order-of-elaboration issues with instances of unchecked
6177 if Nkind (Original_Node (Nod)) = N_Function_Call then
6178 Set_Etype (Nod, Base_Type (Etype (Nod)));
6181 when N_Real_Literal |
6183 N_Character_Literal =>
6187 Check_Expr_Constants (Low_Bound (Nod));
6188 Check_Expr_Constants (High_Bound (Nod));
6190 when N_Explicit_Dereference =>
6191 Check_Expr_Constants (Prefix (Nod));
6193 when N_Indexed_Component =>
6194 Check_Expr_Constants (Prefix (Nod));
6195 Check_List_Constants (Expressions (Nod));
6198 Check_Expr_Constants (Prefix (Nod));
6199 Check_Expr_Constants (Discrete_Range (Nod));
6201 when N_Selected_Component =>
6202 Check_Expr_Constants (Prefix (Nod));
6204 when N_Attribute_Reference =>
6205 if Attribute_Name (Nod) = Name_Address
6207 Attribute_Name (Nod) = Name_Access
6209 Attribute_Name (Nod) = Name_Unchecked_Access
6211 Attribute_Name (Nod) = Name_Unrestricted_Access
6213 Check_At_Constant_Address (Prefix (Nod));
6216 Check_Expr_Constants (Prefix (Nod));
6217 Check_List_Constants (Expressions (Nod));
6221 Check_List_Constants (Component_Associations (Nod));
6222 Check_List_Constants (Expressions (Nod));
6224 when N_Component_Association =>
6225 Check_Expr_Constants (Expression (Nod));
6227 when N_Extension_Aggregate =>
6228 Check_Expr_Constants (Ancestor_Part (Nod));
6229 Check_List_Constants (Component_Associations (Nod));
6230 Check_List_Constants (Expressions (Nod));
6235 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
6236 Check_Expr_Constants (Left_Opnd (Nod));
6237 Check_Expr_Constants (Right_Opnd (Nod));
6240 Check_Expr_Constants (Right_Opnd (Nod));
6242 when N_Type_Conversion |
6243 N_Qualified_Expression |
6245 Check_Expr_Constants (Expression (Nod));
6247 when N_Unchecked_Type_Conversion =>
6248 Check_Expr_Constants (Expression (Nod));
6250 -- If this is a rewritten unchecked conversion, subtypes in
6251 -- this node are those created within the instance. To avoid
6252 -- order of elaboration issues, replace them with their base
6253 -- types. Note that address clauses can cause order of
6254 -- elaboration problems because they are elaborated by the
6255 -- back-end at the point of definition, and may mention
6256 -- entities declared in between (as long as everything is
6257 -- static). It is user-friendly to allow unchecked conversions
6260 if Nkind (Original_Node (Nod)) = N_Function_Call then
6261 Set_Etype (Expression (Nod),
6262 Base_Type (Etype (Expression (Nod))));
6263 Set_Etype (Nod, Base_Type (Etype (Nod)));
6266 when N_Function_Call =>
6267 if not Is_Pure (Entity (Name (Nod))) then
6269 ("invalid address clause for initialized object &!",
6273 ("\function & is not pure (RM 13.1(22))!",
6274 Nod, Entity (Name (Nod)));
6277 Check_List_Constants (Parameter_Associations (Nod));
6280 when N_Parameter_Association =>
6281 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
6285 ("invalid address clause for initialized object &!",
6288 ("\must be constant defined before& (RM 13.1(22))!",
6291 end Check_Expr_Constants;
6293 --------------------------
6294 -- Check_List_Constants --
6295 --------------------------
6297 procedure Check_List_Constants (Lst : List_Id) is
6301 if Present (Lst) then
6302 Nod1 := First (Lst);
6303 while Present (Nod1) loop
6304 Check_Expr_Constants (Nod1);
6308 end Check_List_Constants;
6310 -- Start of processing for Check_Constant_Address_Clause
6313 -- If rep_clauses are to be ignored, no need for legality checks. In
6314 -- particular, no need to pester user about rep clauses that violate
6315 -- the rule on constant addresses, given that these clauses will be
6316 -- removed by Freeze before they reach the back end.
6318 if not Ignore_Rep_Clauses then
6319 Check_Expr_Constants (Expr);
6321 end Check_Constant_Address_Clause;
6323 ----------------------------------------
6324 -- Check_Record_Representation_Clause --
6325 ----------------------------------------
6327 procedure Check_Record_Representation_Clause (N : Node_Id) is
6328 Loc : constant Source_Ptr := Sloc (N);
6329 Ident : constant Node_Id := Identifier (N);
6330 Rectype : Entity_Id;
6335 Hbit : Uint := Uint_0;
6339 Max_Bit_So_Far : Uint;
6340 -- Records the maximum bit position so far. If all field positions
6341 -- are monotonically increasing, then we can skip the circuit for
6342 -- checking for overlap, since no overlap is possible.
6344 Tagged_Parent : Entity_Id := Empty;
6345 -- This is set in the case of a derived tagged type for which we have
6346 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
6347 -- positioned by record representation clauses). In this case we must
6348 -- check for overlap between components of this tagged type, and the
6349 -- components of its parent. Tagged_Parent will point to this parent
6350 -- type. For all other cases Tagged_Parent is left set to Empty.
6352 Parent_Last_Bit : Uint;
6353 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
6354 -- last bit position for any field in the parent type. We only need to
6355 -- check overlap for fields starting below this point.
6357 Overlap_Check_Required : Boolean;
6358 -- Used to keep track of whether or not an overlap check is required
6360 Overlap_Detected : Boolean := False;
6361 -- Set True if an overlap is detected
6363 Ccount : Natural := 0;
6364 -- Number of component clauses in record rep clause
6366 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
6367 -- Given two entities for record components or discriminants, checks
6368 -- if they have overlapping component clauses and issues errors if so.
6370 procedure Find_Component;
6371 -- Finds component entity corresponding to current component clause (in
6372 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
6373 -- start/stop bits for the field. If there is no matching component or
6374 -- if the matching component does not have a component clause, then
6375 -- that's an error and Comp is set to Empty, but no error message is
6376 -- issued, since the message was already given. Comp is also set to
6377 -- Empty if the current "component clause" is in fact a pragma.
6379 -----------------------------
6380 -- Check_Component_Overlap --
6381 -----------------------------
6383 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
6384 CC1 : constant Node_Id := Component_Clause (C1_Ent);
6385 CC2 : constant Node_Id := Component_Clause (C2_Ent);
6388 if Present (CC1) and then Present (CC2) then
6390 -- Exclude odd case where we have two tag fields in the same
6391 -- record, both at location zero. This seems a bit strange, but
6392 -- it seems to happen in some circumstances, perhaps on an error.
6394 if Chars (C1_Ent) = Name_uTag
6396 Chars (C2_Ent) = Name_uTag
6401 -- Here we check if the two fields overlap
6404 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
6405 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
6406 E1 : constant Uint := S1 + Esize (C1_Ent);
6407 E2 : constant Uint := S2 + Esize (C2_Ent);
6410 if E2 <= S1 or else E1 <= S2 then
6413 Error_Msg_Node_2 := Component_Name (CC2);
6414 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6415 Error_Msg_Node_1 := Component_Name (CC1);
6417 ("component& overlaps & #", Component_Name (CC1));
6418 Overlap_Detected := True;
6422 end Check_Component_Overlap;
6424 --------------------
6425 -- Find_Component --
6426 --------------------
6428 procedure Find_Component is
6430 procedure Search_Component (R : Entity_Id);
6431 -- Search components of R for a match. If found, Comp is set.
6433 ----------------------
6434 -- Search_Component --
6435 ----------------------
6437 procedure Search_Component (R : Entity_Id) is
6439 Comp := First_Component_Or_Discriminant (R);
6440 while Present (Comp) loop
6442 -- Ignore error of attribute name for component name (we
6443 -- already gave an error message for this, so no need to
6446 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
6449 exit when Chars (Comp) = Chars (Component_Name (CC));
6452 Next_Component_Or_Discriminant (Comp);
6454 end Search_Component;
6456 -- Start of processing for Find_Component
6459 -- Return with Comp set to Empty if we have a pragma
6461 if Nkind (CC) = N_Pragma then
6466 -- Search current record for matching component
6468 Search_Component (Rectype);
6470 -- If not found, maybe component of base type that is absent from
6471 -- statically constrained first subtype.
6474 Search_Component (Base_Type (Rectype));
6477 -- If no component, or the component does not reference the component
6478 -- clause in question, then there was some previous error for which
6479 -- we already gave a message, so just return with Comp Empty.
6482 or else Component_Clause (Comp) /= CC
6486 -- Normal case where we have a component clause
6489 Fbit := Component_Bit_Offset (Comp);
6490 Lbit := Fbit + Esize (Comp) - 1;
6494 -- Start of processing for Check_Record_Representation_Clause
6498 Rectype := Entity (Ident);
6500 if Rectype = Any_Type then
6503 Rectype := Underlying_Type (Rectype);
6506 -- See if we have a fully repped derived tagged type
6509 PS : constant Entity_Id := Parent_Subtype (Rectype);
6512 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
6513 Tagged_Parent := PS;
6515 -- Find maximum bit of any component of the parent type
6517 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
6518 Pcomp := First_Entity (Tagged_Parent);
6519 while Present (Pcomp) loop
6520 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
6521 if Component_Bit_Offset (Pcomp) /= No_Uint
6522 and then Known_Static_Esize (Pcomp)
6527 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
6530 Next_Entity (Pcomp);
6536 -- All done if no component clauses
6538 CC := First (Component_Clauses (N));
6544 -- If a tag is present, then create a component clause that places it
6545 -- at the start of the record (otherwise gigi may place it after other
6546 -- fields that have rep clauses).
6548 Fent := First_Entity (Rectype);
6550 if Nkind (Fent) = N_Defining_Identifier
6551 and then Chars (Fent) = Name_uTag
6553 Set_Component_Bit_Offset (Fent, Uint_0);
6554 Set_Normalized_Position (Fent, Uint_0);
6555 Set_Normalized_First_Bit (Fent, Uint_0);
6556 Set_Normalized_Position_Max (Fent, Uint_0);
6557 Init_Esize (Fent, System_Address_Size);
6559 Set_Component_Clause (Fent,
6560 Make_Component_Clause (Loc,
6561 Component_Name => Make_Identifier (Loc, Name_uTag),
6563 Position => Make_Integer_Literal (Loc, Uint_0),
6564 First_Bit => Make_Integer_Literal (Loc, Uint_0),
6566 Make_Integer_Literal (Loc,
6567 UI_From_Int (System_Address_Size))));
6569 Ccount := Ccount + 1;
6572 Max_Bit_So_Far := Uint_Minus_1;
6573 Overlap_Check_Required := False;
6575 -- Process the component clauses
6577 while Present (CC) loop
6580 if Present (Comp) then
6581 Ccount := Ccount + 1;
6583 -- We need a full overlap check if record positions non-monotonic
6585 if Fbit <= Max_Bit_So_Far then
6586 Overlap_Check_Required := True;
6589 Max_Bit_So_Far := Lbit;
6591 -- Check bit position out of range of specified size
6593 if Has_Size_Clause (Rectype)
6594 and then RM_Size (Rectype) <= Lbit
6597 ("bit number out of range of specified size",
6600 -- Check for overlap with tag field
6603 if Is_Tagged_Type (Rectype)
6604 and then Fbit < System_Address_Size
6607 ("component overlaps tag field of&",
6608 Component_Name (CC), Rectype);
6609 Overlap_Detected := True;
6617 -- Check parent overlap if component might overlap parent field
6619 if Present (Tagged_Parent)
6620 and then Fbit <= Parent_Last_Bit
6622 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
6623 while Present (Pcomp) loop
6624 if not Is_Tag (Pcomp)
6625 and then Chars (Pcomp) /= Name_uParent
6627 Check_Component_Overlap (Comp, Pcomp);
6630 Next_Component_Or_Discriminant (Pcomp);
6638 -- Now that we have processed all the component clauses, check for
6639 -- overlap. We have to leave this till last, since the components can
6640 -- appear in any arbitrary order in the representation clause.
6642 -- We do not need this check if all specified ranges were monotonic,
6643 -- as recorded by Overlap_Check_Required being False at this stage.
6645 -- This first section checks if there are any overlapping entries at
6646 -- all. It does this by sorting all entries and then seeing if there are
6647 -- any overlaps. If there are none, then that is decisive, but if there
6648 -- are overlaps, they may still be OK (they may result from fields in
6649 -- different variants).
6651 if Overlap_Check_Required then
6652 Overlap_Check1 : declare
6654 OC_Fbit : array (0 .. Ccount) of Uint;
6655 -- First-bit values for component clauses, the value is the offset
6656 -- of the first bit of the field from start of record. The zero
6657 -- entry is for use in sorting.
6659 OC_Lbit : array (0 .. Ccount) of Uint;
6660 -- Last-bit values for component clauses, the value is the offset
6661 -- of the last bit of the field from start of record. The zero
6662 -- entry is for use in sorting.
6664 OC_Count : Natural := 0;
6665 -- Count of entries in OC_Fbit and OC_Lbit
6667 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6668 -- Compare routine for Sort
6670 procedure OC_Move (From : Natural; To : Natural);
6671 -- Move routine for Sort
6673 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6679 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6681 return OC_Fbit (Op1) < OC_Fbit (Op2);
6688 procedure OC_Move (From : Natural; To : Natural) is
6690 OC_Fbit (To) := OC_Fbit (From);
6691 OC_Lbit (To) := OC_Lbit (From);
6694 -- Start of processing for Overlap_Check
6697 CC := First (Component_Clauses (N));
6698 while Present (CC) loop
6700 -- Exclude component clause already marked in error
6702 if not Error_Posted (CC) then
6705 if Present (Comp) then
6706 OC_Count := OC_Count + 1;
6707 OC_Fbit (OC_Count) := Fbit;
6708 OC_Lbit (OC_Count) := Lbit;
6715 Sorting.Sort (OC_Count);
6717 Overlap_Check_Required := False;
6718 for J in 1 .. OC_Count - 1 loop
6719 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6720 Overlap_Check_Required := True;
6727 -- If Overlap_Check_Required is still True, then we have to do the full
6728 -- scale overlap check, since we have at least two fields that do
6729 -- overlap, and we need to know if that is OK since they are in
6730 -- different variant, or whether we have a definite problem.
6732 if Overlap_Check_Required then
6733 Overlap_Check2 : declare
6734 C1_Ent, C2_Ent : Entity_Id;
6735 -- Entities of components being checked for overlap
6738 -- Component_List node whose Component_Items are being checked
6741 -- Component declaration for component being checked
6744 C1_Ent := First_Entity (Base_Type (Rectype));
6746 -- Loop through all components in record. For each component check
6747 -- for overlap with any of the preceding elements on the component
6748 -- list containing the component and also, if the component is in
6749 -- a variant, check against components outside the case structure.
6750 -- This latter test is repeated recursively up the variant tree.
6752 Main_Component_Loop : while Present (C1_Ent) loop
6753 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6754 goto Continue_Main_Component_Loop;
6757 -- Skip overlap check if entity has no declaration node. This
6758 -- happens with discriminants in constrained derived types.
6759 -- Possibly we are missing some checks as a result, but that
6760 -- does not seem terribly serious.
6762 if No (Declaration_Node (C1_Ent)) then
6763 goto Continue_Main_Component_Loop;
6766 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6768 -- Loop through component lists that need checking. Check the
6769 -- current component list and all lists in variants above us.
6771 Component_List_Loop : loop
6773 -- If derived type definition, go to full declaration
6774 -- If at outer level, check discriminants if there are any.
6776 if Nkind (Clist) = N_Derived_Type_Definition then
6777 Clist := Parent (Clist);
6780 -- Outer level of record definition, check discriminants
6782 if Nkind_In (Clist, N_Full_Type_Declaration,
6783 N_Private_Type_Declaration)
6785 if Has_Discriminants (Defining_Identifier (Clist)) then
6787 First_Discriminant (Defining_Identifier (Clist));
6788 while Present (C2_Ent) loop
6789 exit when C1_Ent = C2_Ent;
6790 Check_Component_Overlap (C1_Ent, C2_Ent);
6791 Next_Discriminant (C2_Ent);
6795 -- Record extension case
6797 elsif Nkind (Clist) = N_Derived_Type_Definition then
6800 -- Otherwise check one component list
6803 Citem := First (Component_Items (Clist));
6804 while Present (Citem) loop
6805 if Nkind (Citem) = N_Component_Declaration then
6806 C2_Ent := Defining_Identifier (Citem);
6807 exit when C1_Ent = C2_Ent;
6808 Check_Component_Overlap (C1_Ent, C2_Ent);
6815 -- Check for variants above us (the parent of the Clist can
6816 -- be a variant, in which case its parent is a variant part,
6817 -- and the parent of the variant part is a component list
6818 -- whose components must all be checked against the current
6819 -- component for overlap).
6821 if Nkind (Parent (Clist)) = N_Variant then
6822 Clist := Parent (Parent (Parent (Clist)));
6824 -- Check for possible discriminant part in record, this
6825 -- is treated essentially as another level in the
6826 -- recursion. For this case the parent of the component
6827 -- list is the record definition, and its parent is the
6828 -- full type declaration containing the discriminant
6831 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6832 Clist := Parent (Parent ((Clist)));
6834 -- If neither of these two cases, we are at the top of
6838 exit Component_List_Loop;
6840 end loop Component_List_Loop;
6842 <<Continue_Main_Component_Loop>>
6843 Next_Entity (C1_Ent);
6845 end loop Main_Component_Loop;
6849 -- The following circuit deals with warning on record holes (gaps). We
6850 -- skip this check if overlap was detected, since it makes sense for the
6851 -- programmer to fix this illegality before worrying about warnings.
6853 if not Overlap_Detected and Warn_On_Record_Holes then
6854 Record_Hole_Check : declare
6855 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6856 -- Full declaration of record type
6858 procedure Check_Component_List
6862 -- Check component list CL for holes. The starting bit should be
6863 -- Sbit. which is zero for the main record component list and set
6864 -- appropriately for recursive calls for variants. DS is set to
6865 -- a list of discriminant specifications to be included in the
6866 -- consideration of components. It is No_List if none to consider.
6868 --------------------------
6869 -- Check_Component_List --
6870 --------------------------
6872 procedure Check_Component_List
6880 Compl := Integer (List_Length (Component_Items (CL)));
6882 if DS /= No_List then
6883 Compl := Compl + Integer (List_Length (DS));
6887 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6888 -- Gather components (zero entry is for sort routine)
6890 Ncomps : Natural := 0;
6891 -- Number of entries stored in Comps (starting at Comps (1))
6894 -- One component item or discriminant specification
6897 -- Starting bit for next component
6905 function Lt (Op1, Op2 : Natural) return Boolean;
6906 -- Compare routine for Sort
6908 procedure Move (From : Natural; To : Natural);
6909 -- Move routine for Sort
6911 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6917 function Lt (Op1, Op2 : Natural) return Boolean is
6919 return Component_Bit_Offset (Comps (Op1))
6921 Component_Bit_Offset (Comps (Op2));
6928 procedure Move (From : Natural; To : Natural) is
6930 Comps (To) := Comps (From);
6934 -- Gather discriminants into Comp
6936 if DS /= No_List then
6937 Citem := First (DS);
6938 while Present (Citem) loop
6939 if Nkind (Citem) = N_Discriminant_Specification then
6941 Ent : constant Entity_Id :=
6942 Defining_Identifier (Citem);
6944 if Ekind (Ent) = E_Discriminant then
6945 Ncomps := Ncomps + 1;
6946 Comps (Ncomps) := Ent;
6955 -- Gather component entities into Comp
6957 Citem := First (Component_Items (CL));
6958 while Present (Citem) loop
6959 if Nkind (Citem) = N_Component_Declaration then
6960 Ncomps := Ncomps + 1;
6961 Comps (Ncomps) := Defining_Identifier (Citem);
6967 -- Now sort the component entities based on the first bit.
6968 -- Note we already know there are no overlapping components.
6970 Sorting.Sort (Ncomps);
6972 -- Loop through entries checking for holes
6975 for J in 1 .. Ncomps loop
6977 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6979 if Error_Msg_Uint_1 > 0 then
6981 ("?^-bit gap before component&",
6982 Component_Name (Component_Clause (CEnt)), CEnt);
6985 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
6988 -- Process variant parts recursively if present
6990 if Present (Variant_Part (CL)) then
6991 Variant := First (Variants (Variant_Part (CL)));
6992 while Present (Variant) loop
6993 Check_Component_List
6994 (Component_List (Variant), Nbit, No_List);
6999 end Check_Component_List;
7001 -- Start of processing for Record_Hole_Check
7008 if Is_Tagged_Type (Rectype) then
7009 Sbit := UI_From_Int (System_Address_Size);
7014 if Nkind (Decl) = N_Full_Type_Declaration
7015 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
7017 Check_Component_List
7018 (Component_List (Type_Definition (Decl)),
7020 Discriminant_Specifications (Decl));
7023 end Record_Hole_Check;
7026 -- For records that have component clauses for all components, and whose
7027 -- size is less than or equal to 32, we need to know the size in the
7028 -- front end to activate possible packed array processing where the
7029 -- component type is a record.
7031 -- At this stage Hbit + 1 represents the first unused bit from all the
7032 -- component clauses processed, so if the component clauses are
7033 -- complete, then this is the length of the record.
7035 -- For records longer than System.Storage_Unit, and for those where not
7036 -- all components have component clauses, the back end determines the
7037 -- length (it may for example be appropriate to round up the size
7038 -- to some convenient boundary, based on alignment considerations, etc).
7040 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
7042 -- Nothing to do if at least one component has no component clause
7044 Comp := First_Component_Or_Discriminant (Rectype);
7045 while Present (Comp) loop
7046 exit when No (Component_Clause (Comp));
7047 Next_Component_Or_Discriminant (Comp);
7050 -- If we fall out of loop, all components have component clauses
7051 -- and so we can set the size to the maximum value.
7054 Set_RM_Size (Rectype, Hbit + 1);
7057 end Check_Record_Representation_Clause;
7063 procedure Check_Size
7067 Biased : out Boolean)
7069 UT : constant Entity_Id := Underlying_Type (T);
7075 -- Dismiss cases for generic types or types with previous errors
7078 or else UT = Any_Type
7079 or else Is_Generic_Type (UT)
7080 or else Is_Generic_Type (Root_Type (UT))
7084 -- Check case of bit packed array
7086 elsif Is_Array_Type (UT)
7087 and then Known_Static_Component_Size (UT)
7088 and then Is_Bit_Packed_Array (UT)
7096 Asiz := Component_Size (UT);
7097 Indx := First_Index (UT);
7099 Ityp := Etype (Indx);
7101 -- If non-static bound, then we are not in the business of
7102 -- trying to check the length, and indeed an error will be
7103 -- issued elsewhere, since sizes of non-static array types
7104 -- cannot be set implicitly or explicitly.
7106 if not Is_Static_Subtype (Ityp) then
7110 -- Otherwise accumulate next dimension
7112 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
7113 Expr_Value (Type_Low_Bound (Ityp)) +
7117 exit when No (Indx);
7123 Error_Msg_Uint_1 := Asiz;
7125 ("size for& too small, minimum allowed is ^", N, T);
7126 Set_Esize (T, Asiz);
7127 Set_RM_Size (T, Asiz);
7131 -- All other composite types are ignored
7133 elsif Is_Composite_Type (UT) then
7136 -- For fixed-point types, don't check minimum if type is not frozen,
7137 -- since we don't know all the characteristics of the type that can
7138 -- affect the size (e.g. a specified small) till freeze time.
7140 elsif Is_Fixed_Point_Type (UT)
7141 and then not Is_Frozen (UT)
7145 -- Cases for which a minimum check is required
7148 -- Ignore if specified size is correct for the type
7150 if Known_Esize (UT) and then Siz = Esize (UT) then
7154 -- Otherwise get minimum size
7156 M := UI_From_Int (Minimum_Size (UT));
7160 -- Size is less than minimum size, but one possibility remains
7161 -- that we can manage with the new size if we bias the type.
7163 M := UI_From_Int (Minimum_Size (UT, Biased => True));
7166 Error_Msg_Uint_1 := M;
7168 ("size for& too small, minimum allowed is ^", N, T);
7178 -------------------------
7179 -- Get_Alignment_Value --
7180 -------------------------
7182 function Get_Alignment_Value (Expr : Node_Id) return Uint is
7183 Align : constant Uint := Static_Integer (Expr);
7186 if Align = No_Uint then
7189 elsif Align <= 0 then
7190 Error_Msg_N ("alignment value must be positive", Expr);
7194 for J in Int range 0 .. 64 loop
7196 M : constant Uint := Uint_2 ** J;
7199 exit when M = Align;
7203 ("alignment value must be power of 2", Expr);
7211 end Get_Alignment_Value;
7217 procedure Initialize is
7219 Address_Clause_Checks.Init;
7220 Independence_Checks.Init;
7221 Unchecked_Conversions.Init;
7224 -------------------------
7225 -- Is_Operational_Item --
7226 -------------------------
7228 function Is_Operational_Item (N : Node_Id) return Boolean is
7230 if Nkind (N) /= N_Attribute_Definition_Clause then
7234 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
7236 return Id = Attribute_Input
7237 or else Id = Attribute_Output
7238 or else Id = Attribute_Read
7239 or else Id = Attribute_Write
7240 or else Id = Attribute_External_Tag;
7243 end Is_Operational_Item;
7249 function Minimum_Size
7251 Biased : Boolean := False) return Nat
7253 Lo : Uint := No_Uint;
7254 Hi : Uint := No_Uint;
7255 LoR : Ureal := No_Ureal;
7256 HiR : Ureal := No_Ureal;
7257 LoSet : Boolean := False;
7258 HiSet : Boolean := False;
7262 R_Typ : constant Entity_Id := Root_Type (T);
7265 -- If bad type, return 0
7267 if T = Any_Type then
7270 -- For generic types, just return zero. There cannot be any legitimate
7271 -- need to know such a size, but this routine may be called with a
7272 -- generic type as part of normal processing.
7274 elsif Is_Generic_Type (R_Typ)
7275 or else R_Typ = Any_Type
7279 -- Access types. Normally an access type cannot have a size smaller
7280 -- than the size of System.Address. The exception is on VMS, where
7281 -- we have short and long addresses, and it is possible for an access
7282 -- type to have a short address size (and thus be less than the size
7283 -- of System.Address itself). We simply skip the check for VMS, and
7284 -- leave it to the back end to do the check.
7286 elsif Is_Access_Type (T) then
7287 if OpenVMS_On_Target then
7290 return System_Address_Size;
7293 -- Floating-point types
7295 elsif Is_Floating_Point_Type (T) then
7296 return UI_To_Int (Esize (R_Typ));
7300 elsif Is_Discrete_Type (T) then
7302 -- The following loop is looking for the nearest compile time known
7303 -- bounds following the ancestor subtype chain. The idea is to find
7304 -- the most restrictive known bounds information.
7308 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7313 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
7314 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
7321 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
7322 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
7328 Ancest := Ancestor_Subtype (Ancest);
7331 Ancest := Base_Type (T);
7333 if Is_Generic_Type (Ancest) then
7339 -- Fixed-point types. We can't simply use Expr_Value to get the
7340 -- Corresponding_Integer_Value values of the bounds, since these do not
7341 -- get set till the type is frozen, and this routine can be called
7342 -- before the type is frozen. Similarly the test for bounds being static
7343 -- needs to include the case where we have unanalyzed real literals for
7346 elsif Is_Fixed_Point_Type (T) then
7348 -- The following loop is looking for the nearest compile time known
7349 -- bounds following the ancestor subtype chain. The idea is to find
7350 -- the most restrictive known bounds information.
7354 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7358 -- Note: In the following two tests for LoSet and HiSet, it may
7359 -- seem redundant to test for N_Real_Literal here since normally
7360 -- one would assume that the test for the value being known at
7361 -- compile time includes this case. However, there is a glitch.
7362 -- If the real literal comes from folding a non-static expression,
7363 -- then we don't consider any non- static expression to be known
7364 -- at compile time if we are in configurable run time mode (needed
7365 -- in some cases to give a clearer definition of what is and what
7366 -- is not accepted). So the test is indeed needed. Without it, we
7367 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
7370 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
7371 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
7373 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
7380 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
7381 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
7383 HiR := Expr_Value_R (Type_High_Bound (Ancest));
7389 Ancest := Ancestor_Subtype (Ancest);
7392 Ancest := Base_Type (T);
7394 if Is_Generic_Type (Ancest) then
7400 Lo := UR_To_Uint (LoR / Small_Value (T));
7401 Hi := UR_To_Uint (HiR / Small_Value (T));
7403 -- No other types allowed
7406 raise Program_Error;
7409 -- Fall through with Hi and Lo set. Deal with biased case
7412 and then not Is_Fixed_Point_Type (T)
7413 and then not (Is_Enumeration_Type (T)
7414 and then Has_Non_Standard_Rep (T)))
7415 or else Has_Biased_Representation (T)
7421 -- Signed case. Note that we consider types like range 1 .. -1 to be
7422 -- signed for the purpose of computing the size, since the bounds have
7423 -- to be accommodated in the base type.
7425 if Lo < 0 or else Hi < 0 then
7429 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
7430 -- Note that we accommodate the case where the bounds cross. This
7431 -- can happen either because of the way the bounds are declared
7432 -- or because of the algorithm in Freeze_Fixed_Point_Type.
7446 -- If both bounds are positive, make sure that both are represen-
7447 -- table in the case where the bounds are crossed. This can happen
7448 -- either because of the way the bounds are declared, or because of
7449 -- the algorithm in Freeze_Fixed_Point_Type.
7455 -- S = size, (can accommodate 0 .. (2**size - 1))
7458 while Hi >= Uint_2 ** S loop
7466 ---------------------------
7467 -- New_Stream_Subprogram --
7468 ---------------------------
7470 procedure New_Stream_Subprogram
7474 Nam : TSS_Name_Type)
7476 Loc : constant Source_Ptr := Sloc (N);
7477 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
7478 Subp_Id : Entity_Id;
7479 Subp_Decl : Node_Id;
7483 Defer_Declaration : constant Boolean :=
7484 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
7485 -- For a tagged type, there is a declaration for each stream attribute
7486 -- at the freeze point, and we must generate only a completion of this
7487 -- declaration. We do the same for private types, because the full view
7488 -- might be tagged. Otherwise we generate a declaration at the point of
7489 -- the attribute definition clause.
7491 function Build_Spec return Node_Id;
7492 -- Used for declaration and renaming declaration, so that this is
7493 -- treated as a renaming_as_body.
7499 function Build_Spec return Node_Id is
7500 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
7503 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
7506 Subp_Id := Make_Defining_Identifier (Loc, Sname);
7508 -- S : access Root_Stream_Type'Class
7510 Formals := New_List (
7511 Make_Parameter_Specification (Loc,
7512 Defining_Identifier =>
7513 Make_Defining_Identifier (Loc, Name_S),
7515 Make_Access_Definition (Loc,
7518 Designated_Type (Etype (F)), Loc))));
7520 if Nam = TSS_Stream_Input then
7521 Spec := Make_Function_Specification (Loc,
7522 Defining_Unit_Name => Subp_Id,
7523 Parameter_Specifications => Formals,
7524 Result_Definition => T_Ref);
7529 Make_Parameter_Specification (Loc,
7530 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
7531 Out_Present => Out_P,
7532 Parameter_Type => T_Ref));
7535 Make_Procedure_Specification (Loc,
7536 Defining_Unit_Name => Subp_Id,
7537 Parameter_Specifications => Formals);
7543 -- Start of processing for New_Stream_Subprogram
7546 F := First_Formal (Subp);
7548 if Ekind (Subp) = E_Procedure then
7549 Etyp := Etype (Next_Formal (F));
7551 Etyp := Etype (Subp);
7554 -- Prepare subprogram declaration and insert it as an action on the
7555 -- clause node. The visibility for this entity is used to test for
7556 -- visibility of the attribute definition clause (in the sense of
7557 -- 8.3(23) as amended by AI-195).
7559 if not Defer_Declaration then
7561 Make_Subprogram_Declaration (Loc,
7562 Specification => Build_Spec);
7564 -- For a tagged type, there is always a visible declaration for each
7565 -- stream TSS (it is a predefined primitive operation), and the
7566 -- completion of this declaration occurs at the freeze point, which is
7567 -- not always visible at places where the attribute definition clause is
7568 -- visible. So, we create a dummy entity here for the purpose of
7569 -- tracking the visibility of the attribute definition clause itself.
7573 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
7575 Make_Object_Declaration (Loc,
7576 Defining_Identifier => Subp_Id,
7577 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
7580 Insert_Action (N, Subp_Decl);
7581 Set_Entity (N, Subp_Id);
7584 Make_Subprogram_Renaming_Declaration (Loc,
7585 Specification => Build_Spec,
7586 Name => New_Reference_To (Subp, Loc));
7588 if Defer_Declaration then
7589 Set_TSS (Base_Type (Ent), Subp_Id);
7591 Insert_Action (N, Subp_Decl);
7592 Copy_TSS (Subp_Id, Base_Type (Ent));
7594 end New_Stream_Subprogram;
7596 ------------------------
7597 -- Rep_Item_Too_Early --
7598 ------------------------
7600 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
7602 -- Cannot apply non-operational rep items to generic types
7604 if Is_Operational_Item (N) then
7608 and then Is_Generic_Type (Root_Type (T))
7610 Error_Msg_N ("representation item not allowed for generic type", N);
7614 -- Otherwise check for incomplete type
7616 if Is_Incomplete_Or_Private_Type (T)
7617 and then No (Underlying_Type (T))
7619 (Nkind (N) /= N_Pragma
7620 or else Get_Pragma_Id (N) /= Pragma_Import)
7623 ("representation item must be after full type declaration", N);
7626 -- If the type has incomplete components, a representation clause is
7627 -- illegal but stream attributes and Convention pragmas are correct.
7629 elsif Has_Private_Component (T) then
7630 if Nkind (N) = N_Pragma then
7634 ("representation item must appear after type is fully defined",
7641 end Rep_Item_Too_Early;
7643 -----------------------
7644 -- Rep_Item_Too_Late --
7645 -----------------------
7647 function Rep_Item_Too_Late
7650 FOnly : Boolean := False) return Boolean
7653 Parent_Type : Entity_Id;
7656 -- Output the too late message. Note that this is not considered a
7657 -- serious error, since the effect is simply that we ignore the
7658 -- representation clause in this case.
7664 procedure Too_Late is
7666 Error_Msg_N ("|representation item appears too late!", N);
7669 -- Start of processing for Rep_Item_Too_Late
7672 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7673 -- types, which may be frozen if they appear in a representation clause
7674 -- for a local type.
7677 and then not From_With_Type (T)
7680 S := First_Subtype (T);
7682 if Present (Freeze_Node (S)) then
7684 ("?no more representation items for }", Freeze_Node (S), S);
7689 -- Check for case of non-tagged derived type whose parent either has
7690 -- primitive operations, or is a by reference type (RM 13.1(10)).
7694 and then Is_Derived_Type (T)
7695 and then not Is_Tagged_Type (T)
7697 Parent_Type := Etype (Base_Type (T));
7699 if Has_Primitive_Operations (Parent_Type) then
7702 ("primitive operations already defined for&!", N, Parent_Type);
7705 elsif Is_By_Reference_Type (Parent_Type) then
7708 ("parent type & is a by reference type!", N, Parent_Type);
7713 -- No error, link item into head of chain of rep items for the entity,
7714 -- but avoid chaining if we have an overloadable entity, and the pragma
7715 -- is one that can apply to multiple overloaded entities.
7717 if Is_Overloadable (T)
7718 and then Nkind (N) = N_Pragma
7721 Pname : constant Name_Id := Pragma_Name (N);
7723 if Pname = Name_Convention or else
7724 Pname = Name_Import or else
7725 Pname = Name_Export or else
7726 Pname = Name_External or else
7727 Pname = Name_Interface
7734 Record_Rep_Item (T, N);
7736 end Rep_Item_Too_Late;
7738 -------------------------------------
7739 -- Replace_Type_References_Generic --
7740 -------------------------------------
7742 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7744 function Replace_Node (N : Node_Id) return Traverse_Result;
7745 -- Processes a single node in the traversal procedure below, checking
7746 -- if node N should be replaced, and if so, doing the replacement.
7748 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7749 -- This instantiation provides the body of Replace_Type_References
7755 function Replace_Node (N : Node_Id) return Traverse_Result is
7760 -- Case of identifier
7762 if Nkind (N) = N_Identifier then
7764 -- If not the type name, all done with this node
7766 if Chars (N) /= TName then
7769 -- Otherwise do the replacement and we are done with this node
7772 Replace_Type_Reference (N);
7776 -- Case of selected component (which is what a qualification
7777 -- looks like in the unanalyzed tree, which is what we have.
7779 elsif Nkind (N) = N_Selected_Component then
7781 -- If selector name is not our type, keeping going (we might
7782 -- still have an occurrence of the type in the prefix).
7784 if Nkind (Selector_Name (N)) /= N_Identifier
7785 or else Chars (Selector_Name (N)) /= TName
7789 -- Selector name is our type, check qualification
7792 -- Loop through scopes and prefixes, doing comparison
7797 -- Continue if no more scopes or scope with no name
7799 if No (S) or else Nkind (S) not in N_Has_Chars then
7803 -- Do replace if prefix is an identifier matching the
7804 -- scope that we are currently looking at.
7806 if Nkind (P) = N_Identifier
7807 and then Chars (P) = Chars (S)
7809 Replace_Type_Reference (N);
7813 -- Go check scope above us if prefix is itself of the
7814 -- form of a selected component, whose selector matches
7815 -- the scope we are currently looking at.
7817 if Nkind (P) = N_Selected_Component
7818 and then Nkind (Selector_Name (P)) = N_Identifier
7819 and then Chars (Selector_Name (P)) = Chars (S)
7824 -- For anything else, we don't have a match, so keep on
7825 -- going, there are still some weird cases where we may
7826 -- still have a replacement within the prefix.
7834 -- Continue for any other node kind
7842 Replace_Type_Refs (N);
7843 end Replace_Type_References_Generic;
7845 -------------------------
7846 -- Same_Representation --
7847 -------------------------
7849 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7850 T1 : constant Entity_Id := Underlying_Type (Typ1);
7851 T2 : constant Entity_Id := Underlying_Type (Typ2);
7854 -- A quick check, if base types are the same, then we definitely have
7855 -- the same representation, because the subtype specific representation
7856 -- attributes (Size and Alignment) do not affect representation from
7857 -- the point of view of this test.
7859 if Base_Type (T1) = Base_Type (T2) then
7862 elsif Is_Private_Type (Base_Type (T2))
7863 and then Base_Type (T1) = Full_View (Base_Type (T2))
7868 -- Tagged types never have differing representations
7870 if Is_Tagged_Type (T1) then
7874 -- Representations are definitely different if conventions differ
7876 if Convention (T1) /= Convention (T2) then
7880 -- Representations are different if component alignments differ
7882 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7884 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7885 and then Component_Alignment (T1) /= Component_Alignment (T2)
7890 -- For arrays, the only real issue is component size. If we know the
7891 -- component size for both arrays, and it is the same, then that's
7892 -- good enough to know we don't have a change of representation.
7894 if Is_Array_Type (T1) then
7895 if Known_Component_Size (T1)
7896 and then Known_Component_Size (T2)
7897 and then Component_Size (T1) = Component_Size (T2)
7899 if VM_Target = No_VM then
7902 -- In VM targets the representation of arrays with aliased
7903 -- components differs from arrays with non-aliased components
7906 return Has_Aliased_Components (Base_Type (T1))
7908 Has_Aliased_Components (Base_Type (T2));
7913 -- Types definitely have same representation if neither has non-standard
7914 -- representation since default representations are always consistent.
7915 -- If only one has non-standard representation, and the other does not,
7916 -- then we consider that they do not have the same representation. They
7917 -- might, but there is no way of telling early enough.
7919 if Has_Non_Standard_Rep (T1) then
7920 if not Has_Non_Standard_Rep (T2) then
7924 return not Has_Non_Standard_Rep (T2);
7927 -- Here the two types both have non-standard representation, and we need
7928 -- to determine if they have the same non-standard representation.
7930 -- For arrays, we simply need to test if the component sizes are the
7931 -- same. Pragma Pack is reflected in modified component sizes, so this
7932 -- check also deals with pragma Pack.
7934 if Is_Array_Type (T1) then
7935 return Component_Size (T1) = Component_Size (T2);
7937 -- Tagged types always have the same representation, because it is not
7938 -- possible to specify different representations for common fields.
7940 elsif Is_Tagged_Type (T1) then
7943 -- Case of record types
7945 elsif Is_Record_Type (T1) then
7947 -- Packed status must conform
7949 if Is_Packed (T1) /= Is_Packed (T2) then
7952 -- Otherwise we must check components. Typ2 maybe a constrained
7953 -- subtype with fewer components, so we compare the components
7954 -- of the base types.
7957 Record_Case : declare
7958 CD1, CD2 : Entity_Id;
7960 function Same_Rep return Boolean;
7961 -- CD1 and CD2 are either components or discriminants. This
7962 -- function tests whether the two have the same representation
7968 function Same_Rep return Boolean is
7970 if No (Component_Clause (CD1)) then
7971 return No (Component_Clause (CD2));
7975 Present (Component_Clause (CD2))
7977 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7979 Esize (CD1) = Esize (CD2);
7983 -- Start of processing for Record_Case
7986 if Has_Discriminants (T1) then
7987 CD1 := First_Discriminant (T1);
7988 CD2 := First_Discriminant (T2);
7990 -- The number of discriminants may be different if the
7991 -- derived type has fewer (constrained by values). The
7992 -- invisible discriminants retain the representation of
7993 -- the original, so the discrepancy does not per se
7994 -- indicate a different representation.
7997 and then Present (CD2)
7999 if not Same_Rep then
8002 Next_Discriminant (CD1);
8003 Next_Discriminant (CD2);
8008 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
8009 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
8011 while Present (CD1) loop
8012 if not Same_Rep then
8015 Next_Component (CD1);
8016 Next_Component (CD2);
8024 -- For enumeration types, we must check each literal to see if the
8025 -- representation is the same. Note that we do not permit enumeration
8026 -- representation clauses for Character and Wide_Character, so these
8027 -- cases were already dealt with.
8029 elsif Is_Enumeration_Type (T1) then
8030 Enumeration_Case : declare
8034 L1 := First_Literal (T1);
8035 L2 := First_Literal (T2);
8037 while Present (L1) loop
8038 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
8048 end Enumeration_Case;
8050 -- Any other types have the same representation for these purposes
8055 end Same_Representation;
8061 procedure Set_Biased
8065 Biased : Boolean := True)
8069 Set_Has_Biased_Representation (E);
8071 if Warn_On_Biased_Representation then
8073 ("?" & Msg & " forces biased representation for&", N, E);
8078 --------------------
8079 -- Set_Enum_Esize --
8080 --------------------
8082 procedure Set_Enum_Esize (T : Entity_Id) is
8090 -- Find the minimum standard size (8,16,32,64) that fits
8092 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
8093 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
8096 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
8097 Sz := Standard_Character_Size; -- May be > 8 on some targets
8099 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
8102 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
8105 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
8110 if Hi < Uint_2**08 then
8111 Sz := Standard_Character_Size; -- May be > 8 on some targets
8113 elsif Hi < Uint_2**16 then
8116 elsif Hi < Uint_2**32 then
8119 else pragma Assert (Hi < Uint_2**63);
8124 -- That minimum is the proper size unless we have a foreign convention
8125 -- and the size required is 32 or less, in which case we bump the size
8126 -- up to 32. This is required for C and C++ and seems reasonable for
8127 -- all other foreign conventions.
8129 if Has_Foreign_Convention (T)
8130 and then Esize (T) < Standard_Integer_Size
8132 Init_Esize (T, Standard_Integer_Size);
8138 ------------------------------
8139 -- Validate_Address_Clauses --
8140 ------------------------------
8142 procedure Validate_Address_Clauses is
8144 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
8146 ACCR : Address_Clause_Check_Record
8147 renames Address_Clause_Checks.Table (J);
8158 -- Skip processing of this entry if warning already posted
8160 if not Address_Warning_Posted (ACCR.N) then
8162 Expr := Original_Node (Expression (ACCR.N));
8166 X_Alignment := Alignment (ACCR.X);
8167 Y_Alignment := Alignment (ACCR.Y);
8169 -- Similarly obtain sizes
8171 X_Size := Esize (ACCR.X);
8172 Y_Size := Esize (ACCR.Y);
8174 -- Check for large object overlaying smaller one
8177 and then X_Size > Uint_0
8178 and then X_Size > Y_Size
8181 ("?& overlays smaller object", ACCR.N, ACCR.X);
8183 ("\?program execution may be erroneous", ACCR.N);
8184 Error_Msg_Uint_1 := X_Size;
8186 ("\?size of & is ^", ACCR.N, ACCR.X);
8187 Error_Msg_Uint_1 := Y_Size;
8189 ("\?size of & is ^", ACCR.N, ACCR.Y);
8191 -- Check for inadequate alignment, both of the base object
8192 -- and of the offset, if any.
8194 -- Note: we do not check the alignment if we gave a size
8195 -- warning, since it would likely be redundant.
8197 elsif Y_Alignment /= Uint_0
8198 and then (Y_Alignment < X_Alignment
8201 Nkind (Expr) = N_Attribute_Reference
8203 Attribute_Name (Expr) = Name_Address
8205 Has_Compatible_Alignment
8206 (ACCR.X, Prefix (Expr))
8207 /= Known_Compatible))
8210 ("?specified address for& may be inconsistent "
8214 ("\?program execution may be erroneous (RM 13.3(27))",
8216 Error_Msg_Uint_1 := X_Alignment;
8218 ("\?alignment of & is ^",
8220 Error_Msg_Uint_1 := Y_Alignment;
8222 ("\?alignment of & is ^",
8224 if Y_Alignment >= X_Alignment then
8226 ("\?but offset is not multiple of alignment",
8233 end Validate_Address_Clauses;
8235 ---------------------------
8236 -- Validate_Independence --
8237 ---------------------------
8239 procedure Validate_Independence is
8240 SU : constant Uint := UI_From_Int (System_Storage_Unit);
8248 procedure Check_Array_Type (Atyp : Entity_Id);
8249 -- Checks if the array type Atyp has independent components, and
8250 -- if not, outputs an appropriate set of error messages.
8252 procedure No_Independence;
8253 -- Output message that independence cannot be guaranteed
8255 function OK_Component (C : Entity_Id) return Boolean;
8256 -- Checks one component to see if it is independently accessible, and
8257 -- if so yields True, otherwise yields False if independent access
8258 -- cannot be guaranteed. This is a conservative routine, it only
8259 -- returns True if it knows for sure, it returns False if it knows
8260 -- there is a problem, or it cannot be sure there is no problem.
8262 procedure Reason_Bad_Component (C : Entity_Id);
8263 -- Outputs continuation message if a reason can be determined for
8264 -- the component C being bad.
8266 ----------------------
8267 -- Check_Array_Type --
8268 ----------------------
8270 procedure Check_Array_Type (Atyp : Entity_Id) is
8271 Ctyp : constant Entity_Id := Component_Type (Atyp);
8274 -- OK if no alignment clause, no pack, and no component size
8276 if not Has_Component_Size_Clause (Atyp)
8277 and then not Has_Alignment_Clause (Atyp)
8278 and then not Is_Packed (Atyp)
8283 -- Check actual component size
8285 if not Known_Component_Size (Atyp)
8286 or else not (Addressable (Component_Size (Atyp))
8287 and then Component_Size (Atyp) < 64)
8288 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
8292 -- Bad component size, check reason
8294 if Has_Component_Size_Clause (Atyp) then
8296 Get_Attribute_Definition_Clause
8297 (Atyp, Attribute_Component_Size);
8300 Error_Msg_Sloc := Sloc (P);
8301 Error_Msg_N ("\because of Component_Size clause#", N);
8306 if Is_Packed (Atyp) then
8307 P := Get_Rep_Pragma (Atyp, Name_Pack);
8310 Error_Msg_Sloc := Sloc (P);
8311 Error_Msg_N ("\because of pragma Pack#", N);
8316 -- No reason found, just return
8321 -- Array type is OK independence-wise
8324 end Check_Array_Type;
8326 ---------------------
8327 -- No_Independence --
8328 ---------------------
8330 procedure No_Independence is
8332 if Pragma_Name (N) = Name_Independent then
8334 ("independence cannot be guaranteed for&", N, E);
8337 ("independent components cannot be guaranteed for&", N, E);
8339 end No_Independence;
8345 function OK_Component (C : Entity_Id) return Boolean is
8346 Rec : constant Entity_Id := Scope (C);
8347 Ctyp : constant Entity_Id := Etype (C);
8350 -- OK if no component clause, no Pack, and no alignment clause
8352 if No (Component_Clause (C))
8353 and then not Is_Packed (Rec)
8354 and then not Has_Alignment_Clause (Rec)
8359 -- Here we look at the actual component layout. A component is
8360 -- addressable if its size is a multiple of the Esize of the
8361 -- component type, and its starting position in the record has
8362 -- appropriate alignment, and the record itself has appropriate
8363 -- alignment to guarantee the component alignment.
8365 -- Make sure sizes are static, always assume the worst for any
8366 -- cases where we cannot check static values.
8368 if not (Known_Static_Esize (C)
8369 and then Known_Static_Esize (Ctyp))
8374 -- Size of component must be addressable or greater than 64 bits
8375 -- and a multiple of bytes.
8377 if not Addressable (Esize (C))
8378 and then Esize (C) < Uint_64
8383 -- Check size is proper multiple
8385 if Esize (C) mod Esize (Ctyp) /= 0 then
8389 -- Check alignment of component is OK
8391 if not Known_Component_Bit_Offset (C)
8392 or else Component_Bit_Offset (C) < Uint_0
8393 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
8398 -- Check alignment of record type is OK
8400 if not Known_Alignment (Rec)
8401 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8406 -- All tests passed, component is addressable
8411 --------------------------
8412 -- Reason_Bad_Component --
8413 --------------------------
8415 procedure Reason_Bad_Component (C : Entity_Id) is
8416 Rec : constant Entity_Id := Scope (C);
8417 Ctyp : constant Entity_Id := Etype (C);
8420 -- If component clause present assume that's the problem
8422 if Present (Component_Clause (C)) then
8423 Error_Msg_Sloc := Sloc (Component_Clause (C));
8424 Error_Msg_N ("\because of Component_Clause#", N);
8428 -- If pragma Pack clause present, assume that's the problem
8430 if Is_Packed (Rec) then
8431 P := Get_Rep_Pragma (Rec, Name_Pack);
8434 Error_Msg_Sloc := Sloc (P);
8435 Error_Msg_N ("\because of pragma Pack#", N);
8440 -- See if record has bad alignment clause
8442 if Has_Alignment_Clause (Rec)
8443 and then Known_Alignment (Rec)
8444 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8446 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
8449 Error_Msg_Sloc := Sloc (P);
8450 Error_Msg_N ("\because of Alignment clause#", N);
8454 -- Couldn't find a reason, so return without a message
8457 end Reason_Bad_Component;
8459 -- Start of processing for Validate_Independence
8462 for J in Independence_Checks.First .. Independence_Checks.Last loop
8463 N := Independence_Checks.Table (J).N;
8464 E := Independence_Checks.Table (J).E;
8465 IC := Pragma_Name (N) = Name_Independent_Components;
8467 -- Deal with component case
8469 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
8470 if not OK_Component (E) then
8472 Reason_Bad_Component (E);
8477 -- Deal with record with Independent_Components
8479 if IC and then Is_Record_Type (E) then
8480 Comp := First_Component_Or_Discriminant (E);
8481 while Present (Comp) loop
8482 if not OK_Component (Comp) then
8484 Reason_Bad_Component (Comp);
8488 Next_Component_Or_Discriminant (Comp);
8492 -- Deal with address clause case
8494 if Is_Object (E) then
8495 Addr := Address_Clause (E);
8497 if Present (Addr) then
8499 Error_Msg_Sloc := Sloc (Addr);
8500 Error_Msg_N ("\because of Address clause#", N);
8505 -- Deal with independent components for array type
8507 if IC and then Is_Array_Type (E) then
8508 Check_Array_Type (E);
8511 -- Deal with independent components for array object
8513 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
8514 Check_Array_Type (Etype (E));
8519 end Validate_Independence;
8521 -----------------------------------
8522 -- Validate_Unchecked_Conversion --
8523 -----------------------------------
8525 procedure Validate_Unchecked_Conversion
8527 Act_Unit : Entity_Id)
8534 -- Obtain source and target types. Note that we call Ancestor_Subtype
8535 -- here because the processing for generic instantiation always makes
8536 -- subtypes, and we want the original frozen actual types.
8538 -- If we are dealing with private types, then do the check on their
8539 -- fully declared counterparts if the full declarations have been
8540 -- encountered (they don't have to be visible, but they must exist!)
8542 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
8544 if Is_Private_Type (Source)
8545 and then Present (Underlying_Type (Source))
8547 Source := Underlying_Type (Source);
8550 Target := Ancestor_Subtype (Etype (Act_Unit));
8552 -- If either type is generic, the instantiation happens within a generic
8553 -- unit, and there is nothing to check. The proper check
8554 -- will happen when the enclosing generic is instantiated.
8556 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
8560 if Is_Private_Type (Target)
8561 and then Present (Underlying_Type (Target))
8563 Target := Underlying_Type (Target);
8566 -- Source may be unconstrained array, but not target
8568 if Is_Array_Type (Target)
8569 and then not Is_Constrained (Target)
8572 ("unchecked conversion to unconstrained array not allowed", N);
8576 -- Warn if conversion between two different convention pointers
8578 if Is_Access_Type (Target)
8579 and then Is_Access_Type (Source)
8580 and then Convention (Target) /= Convention (Source)
8581 and then Warn_On_Unchecked_Conversion
8583 -- Give warnings for subprogram pointers only on most targets. The
8584 -- exception is VMS, where data pointers can have different lengths
8585 -- depending on the pointer convention.
8587 if Is_Access_Subprogram_Type (Target)
8588 or else Is_Access_Subprogram_Type (Source)
8589 or else OpenVMS_On_Target
8592 ("?conversion between pointers with different conventions!", N);
8596 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
8597 -- warning when compiling GNAT-related sources.
8599 if Warn_On_Unchecked_Conversion
8600 and then not In_Predefined_Unit (N)
8601 and then RTU_Loaded (Ada_Calendar)
8603 (Chars (Source) = Name_Time
8605 Chars (Target) = Name_Time)
8607 -- If Ada.Calendar is loaded and the name of one of the operands is
8608 -- Time, there is a good chance that this is Ada.Calendar.Time.
8611 Calendar_Time : constant Entity_Id :=
8612 Full_View (RTE (RO_CA_Time));
8614 pragma Assert (Present (Calendar_Time));
8616 if Source = Calendar_Time
8617 or else Target = Calendar_Time
8620 ("?representation of 'Time values may change between " &
8621 "'G'N'A'T versions", N);
8626 -- Make entry in unchecked conversion table for later processing by
8627 -- Validate_Unchecked_Conversions, which will check sizes and alignments
8628 -- (using values set by the back-end where possible). This is only done
8629 -- if the appropriate warning is active.
8631 if Warn_On_Unchecked_Conversion then
8632 Unchecked_Conversions.Append
8633 (New_Val => UC_Entry'
8638 -- If both sizes are known statically now, then back end annotation
8639 -- is not required to do a proper check but if either size is not
8640 -- known statically, then we need the annotation.
8642 if Known_Static_RM_Size (Source)
8643 and then Known_Static_RM_Size (Target)
8647 Back_Annotate_Rep_Info := True;
8651 -- If unchecked conversion to access type, and access type is declared
8652 -- in the same unit as the unchecked conversion, then set the
8653 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
8656 if Is_Access_Type (Target) and then
8657 In_Same_Source_Unit (Target, N)
8659 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
8662 -- Generate N_Validate_Unchecked_Conversion node for back end in
8663 -- case the back end needs to perform special validation checks.
8665 -- Shouldn't this be in Exp_Ch13, since the check only gets done
8666 -- if we have full expansion and the back end is called ???
8669 Make_Validate_Unchecked_Conversion (Sloc (N));
8670 Set_Source_Type (Vnode, Source);
8671 Set_Target_Type (Vnode, Target);
8673 -- If the unchecked conversion node is in a list, just insert before it.
8674 -- If not we have some strange case, not worth bothering about.
8676 if Is_List_Member (N) then
8677 Insert_After (N, Vnode);
8679 end Validate_Unchecked_Conversion;
8681 ------------------------------------
8682 -- Validate_Unchecked_Conversions --
8683 ------------------------------------
8685 procedure Validate_Unchecked_Conversions is
8687 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8689 T : UC_Entry renames Unchecked_Conversions.Table (N);
8691 Eloc : constant Source_Ptr := T.Eloc;
8692 Source : constant Entity_Id := T.Source;
8693 Target : constant Entity_Id := T.Target;
8699 -- This validation check, which warns if we have unequal sizes for
8700 -- unchecked conversion, and thus potentially implementation
8701 -- dependent semantics, is one of the few occasions on which we
8702 -- use the official RM size instead of Esize. See description in
8703 -- Einfo "Handling of Type'Size Values" for details.
8705 if Serious_Errors_Detected = 0
8706 and then Known_Static_RM_Size (Source)
8707 and then Known_Static_RM_Size (Target)
8709 -- Don't do the check if warnings off for either type, note the
8710 -- deliberate use of OR here instead of OR ELSE to get the flag
8711 -- Warnings_Off_Used set for both types if appropriate.
8713 and then not (Has_Warnings_Off (Source)
8715 Has_Warnings_Off (Target))
8717 Source_Siz := RM_Size (Source);
8718 Target_Siz := RM_Size (Target);
8720 if Source_Siz /= Target_Siz then
8722 ("?types for unchecked conversion have different sizes!",
8725 if All_Errors_Mode then
8726 Error_Msg_Name_1 := Chars (Source);
8727 Error_Msg_Uint_1 := Source_Siz;
8728 Error_Msg_Name_2 := Chars (Target);
8729 Error_Msg_Uint_2 := Target_Siz;
8730 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8732 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8734 if Is_Discrete_Type (Source)
8735 and then Is_Discrete_Type (Target)
8737 if Source_Siz > Target_Siz then
8739 ("\?^ high order bits of source will be ignored!",
8742 elsif Is_Unsigned_Type (Source) then
8744 ("\?source will be extended with ^ high order " &
8745 "zero bits?!", Eloc);
8749 ("\?source will be extended with ^ high order " &
8754 elsif Source_Siz < Target_Siz then
8755 if Is_Discrete_Type (Target) then
8756 if Bytes_Big_Endian then
8758 ("\?target value will include ^ undefined " &
8763 ("\?target value will include ^ undefined " &
8770 ("\?^ trailing bits of target value will be " &
8771 "undefined!", Eloc);
8774 else pragma Assert (Source_Siz > Target_Siz);
8776 ("\?^ trailing bits of source will be ignored!",
8783 -- If both types are access types, we need to check the alignment.
8784 -- If the alignment of both is specified, we can do it here.
8786 if Serious_Errors_Detected = 0
8787 and then Ekind (Source) in Access_Kind
8788 and then Ekind (Target) in Access_Kind
8789 and then Target_Strict_Alignment
8790 and then Present (Designated_Type (Source))
8791 and then Present (Designated_Type (Target))
8794 D_Source : constant Entity_Id := Designated_Type (Source);
8795 D_Target : constant Entity_Id := Designated_Type (Target);
8798 if Known_Alignment (D_Source)
8799 and then Known_Alignment (D_Target)
8802 Source_Align : constant Uint := Alignment (D_Source);
8803 Target_Align : constant Uint := Alignment (D_Target);
8806 if Source_Align < Target_Align
8807 and then not Is_Tagged_Type (D_Source)
8809 -- Suppress warning if warnings suppressed on either
8810 -- type or either designated type. Note the use of
8811 -- OR here instead of OR ELSE. That is intentional,
8812 -- we would like to set flag Warnings_Off_Used in
8813 -- all types for which warnings are suppressed.
8815 and then not (Has_Warnings_Off (D_Source)
8817 Has_Warnings_Off (D_Target)
8819 Has_Warnings_Off (Source)
8821 Has_Warnings_Off (Target))
8823 Error_Msg_Uint_1 := Target_Align;
8824 Error_Msg_Uint_2 := Source_Align;
8825 Error_Msg_Node_1 := D_Target;
8826 Error_Msg_Node_2 := D_Source;
8828 ("?alignment of & (^) is stricter than " &
8829 "alignment of & (^)!", Eloc);
8831 ("\?resulting access value may have invalid " &
8832 "alignment!", Eloc);
8840 end Validate_Unchecked_Conversions;
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