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 -- Check placement legality: An invariant must apply to a
1293 -- private type, or appear in the private part of a spec.
1294 -- Analysis of the pragma will verify that in the private
1295 -- part it applies to a completion.
1297 if Nkind_In (N, N_Private_Type_Declaration,
1298 N_Private_Extension_Declaration)
1302 elsif Nkind (N) = N_Full_Type_Declaration
1303 and then In_Private_Part (Current_Scope)
1309 ("invariant aspect must apply to a private type", N);
1312 -- Construct the pragma
1316 Pragma_Argument_Associations =>
1317 New_List (Ent, Relocate_Node (Expr)),
1318 Class_Present => Class_Present (Aspect),
1319 Pragma_Identifier =>
1320 Make_Identifier (Sloc (Id), Name_Invariant));
1322 -- Add message unless exception messages are suppressed
1324 if not Opt.Exception_Locations_Suppressed then
1325 Append_To (Pragma_Argument_Associations (Aitem),
1326 Make_Pragma_Argument_Association (Eloc,
1327 Chars => Name_Message,
1329 Make_String_Literal (Eloc,
1330 Strval => "failed invariant from "
1331 & Build_Location_String (Eloc))));
1334 Set_From_Aspect_Specification (Aitem, True);
1335 Set_Is_Delayed_Aspect (Aspect);
1337 -- For Invariant case, insert immediately after the entity
1338 -- declaration. We do not have to worry about delay issues
1339 -- since the pragma processing takes care of this.
1341 Insert_After (N, Aitem);
1344 -- Predicate aspects generate a corresponding pragma with a
1345 -- first argument that is the entity, and the second argument
1346 -- is the expression.
1348 when Aspect_Dynamic_Predicate |
1350 Aspect_Static_Predicate =>
1352 -- Construct the pragma (always a pragma Predicate, with
1353 -- flags recording whether it is static/dynamic).
1357 Pragma_Argument_Associations =>
1358 New_List (Ent, Relocate_Node (Expr)),
1359 Class_Present => Class_Present (Aspect),
1360 Pragma_Identifier =>
1361 Make_Identifier (Sloc (Id), Name_Predicate));
1363 Set_From_Aspect_Specification (Aitem, True);
1365 -- Set special flags for dynamic/static cases
1367 if A_Id = Aspect_Dynamic_Predicate then
1368 Set_From_Dynamic_Predicate (Aitem);
1369 elsif A_Id = Aspect_Static_Predicate then
1370 Set_From_Static_Predicate (Aitem);
1373 -- Make sure we have a freeze node (it might otherwise be
1374 -- missing in cases like subtype X is Y, and we would not
1375 -- have a place to build the predicate function).
1377 Set_Has_Predicates (E);
1379 if Is_Private_Type (E)
1380 and then Present (Full_View (E))
1382 Set_Has_Predicates (Full_View (E));
1383 Set_Has_Delayed_Aspects (Full_View (E));
1386 Ensure_Freeze_Node (E);
1387 Set_Is_Delayed_Aspect (Aspect);
1388 Delay_Required := True;
1390 when Aspect_Test_Case => declare
1392 Comp_Expr : Node_Id;
1393 Comp_Assn : Node_Id;
1398 if Nkind (Parent (N)) = N_Compilation_Unit then
1400 ("incorrect placement of aspect `Test_Case`", E);
1404 if Nkind (Expr) /= N_Aggregate then
1406 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1410 Comp_Expr := First (Expressions (Expr));
1411 while Present (Comp_Expr) loop
1412 Append (Relocate_Node (Comp_Expr), Args);
1416 Comp_Assn := First (Component_Associations (Expr));
1417 while Present (Comp_Assn) loop
1418 if List_Length (Choices (Comp_Assn)) /= 1
1420 Nkind (First (Choices (Comp_Assn))) /= N_Identifier
1423 ("wrong syntax for aspect `Test_Case` for &", Id, E);
1427 Append (Make_Pragma_Argument_Association (
1428 Sloc => Sloc (Comp_Assn),
1429 Chars => Chars (First (Choices (Comp_Assn))),
1430 Expression => Relocate_Node (Expression (Comp_Assn))),
1435 -- Build the test-case pragma
1439 Pragma_Identifier =>
1440 Make_Identifier (Sloc (Id), Name_Test_Case),
1441 Pragma_Argument_Associations =>
1444 Set_From_Aspect_Specification (Aitem, True);
1445 Set_Is_Delayed_Aspect (Aspect);
1447 -- Insert immediately after the entity declaration
1449 Insert_After (N, Aitem);
1455 -- If a delay is required, we delay the freeze (not much point in
1456 -- delaying the aspect if we don't delay the freeze!). The pragma
1457 -- or attribute clause if there is one is then attached to the
1458 -- aspect specification which is placed in the rep item list.
1460 if Delay_Required then
1461 if Present (Aitem) then
1462 Set_From_Aspect_Specification (Aitem, True);
1463 Set_Is_Delayed_Aspect (Aitem);
1464 Set_Aspect_Rep_Item (Aspect, Aitem);
1467 Ensure_Freeze_Node (E);
1468 Set_Has_Delayed_Aspects (E);
1469 Record_Rep_Item (E, Aspect);
1471 -- If no delay required, insert the pragma/clause in the tree
1474 Set_From_Aspect_Specification (Aitem, True);
1476 -- If this is a compilation unit, we will put the pragma in
1477 -- the Pragmas_After list of the N_Compilation_Unit_Aux node.
1479 if Nkind (Parent (Ins_Node)) = N_Compilation_Unit then
1481 Aux : constant Node_Id :=
1482 Aux_Decls_Node (Parent (Ins_Node));
1485 pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux);
1487 if No (Pragmas_After (Aux)) then
1488 Set_Pragmas_After (Aux, Empty_List);
1491 -- For Pre_Post put at start of list, otherwise at end
1493 if A_Id in Pre_Post_Aspects then
1494 Prepend (Aitem, Pragmas_After (Aux));
1496 Append (Aitem, Pragmas_After (Aux));
1500 -- Here if not compilation unit case
1505 -- For Pre/Post cases, insert immediately after the
1506 -- entity declaration, since that is the required pragma
1509 when Pre_Post_Aspects =>
1510 Insert_After (N, Aitem);
1512 -- For Priority aspects, insert into the task or
1513 -- protected definition, which we need to create if it's
1514 -- not there. The same applies to CPU and
1515 -- Dispatching_Domain but only to tasks.
1517 when Aspect_Priority |
1518 Aspect_Interrupt_Priority |
1519 Aspect_Dispatching_Domain |
1522 T : Node_Id; -- the type declaration
1523 L : List_Id; -- list of decls of task/protected
1526 if Nkind (N) = N_Object_Declaration then
1527 T := Parent (Etype (Defining_Identifier (N)));
1532 if Nkind (T) = N_Protected_Type_Declaration
1533 and then A_Id /= Aspect_Dispatching_Domain
1534 and then A_Id /= Aspect_CPU
1537 (Present (Protected_Definition (T)));
1539 L := Visible_Declarations
1540 (Protected_Definition (T));
1542 elsif Nkind (T) = N_Task_Type_Declaration then
1543 if No (Task_Definition (T)) then
1546 Make_Task_Definition
1548 Visible_Declarations => New_List,
1549 End_Label => Empty));
1552 L := Visible_Declarations (Task_Definition (T));
1555 raise Program_Error;
1558 Prepend (Aitem, To => L);
1560 -- Analyze rewritten pragma. Otherwise, its
1561 -- analysis is done too late, after the task or
1562 -- protected object has been created.
1567 -- For all other cases, insert in sequence
1570 Insert_After (Ins_Node, Aitem);
1579 end loop Aspect_Loop;
1580 end Analyze_Aspect_Specifications;
1582 -----------------------
1583 -- Analyze_At_Clause --
1584 -----------------------
1586 -- An at clause is replaced by the corresponding Address attribute
1587 -- definition clause that is the preferred approach in Ada 95.
1589 procedure Analyze_At_Clause (N : Node_Id) is
1590 CS : constant Boolean := Comes_From_Source (N);
1593 -- This is an obsolescent feature
1595 Check_Restriction (No_Obsolescent_Features, N);
1597 if Warn_On_Obsolescent_Feature then
1599 ("at clause is an obsolescent feature (RM J.7(2))?", N);
1601 ("\use address attribute definition clause instead?", N);
1604 -- Rewrite as address clause
1607 Make_Attribute_Definition_Clause (Sloc (N),
1608 Name => Identifier (N),
1609 Chars => Name_Address,
1610 Expression => Expression (N)));
1612 -- We preserve Comes_From_Source, since logically the clause still
1613 -- comes from the source program even though it is changed in form.
1615 Set_Comes_From_Source (N, CS);
1617 -- Analyze rewritten clause
1619 Analyze_Attribute_Definition_Clause (N);
1620 end Analyze_At_Clause;
1622 -----------------------------------------
1623 -- Analyze_Attribute_Definition_Clause --
1624 -----------------------------------------
1626 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
1627 Loc : constant Source_Ptr := Sloc (N);
1628 Nam : constant Node_Id := Name (N);
1629 Attr : constant Name_Id := Chars (N);
1630 Expr : constant Node_Id := Expression (N);
1631 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
1634 -- The entity of Nam after it is analyzed. In the case of an incomplete
1635 -- type, this is the underlying type.
1638 -- The underlying entity to which the attribute applies. Generally this
1639 -- is the Underlying_Type of Ent, except in the case where the clause
1640 -- applies to full view of incomplete type or private type in which case
1641 -- U_Ent is just a copy of Ent.
1643 FOnly : Boolean := False;
1644 -- Reset to True for subtype specific attribute (Alignment, Size)
1645 -- and for stream attributes, i.e. those cases where in the call
1646 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
1647 -- rules are checked. Note that the case of stream attributes is not
1648 -- clear from the RM, but see AI95-00137. Also, the RM seems to
1649 -- disallow Storage_Size for derived task types, but that is also
1650 -- clearly unintentional.
1652 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
1653 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
1654 -- definition clauses.
1656 function Duplicate_Clause return Boolean;
1657 -- This routine checks if the aspect for U_Ent being given by attribute
1658 -- definition clause N is for an aspect that has already been specified,
1659 -- and if so gives an error message. If there is a duplicate, True is
1660 -- returned, otherwise if there is no error, False is returned.
1662 procedure Check_Indexing_Functions;
1663 -- Check that the function in Constant_Indexing or Variable_Indexing
1664 -- attribute has the proper type structure. If the name is overloaded,
1665 -- check that all interpretations are legal.
1667 procedure Check_Iterator_Functions;
1668 -- Check that there is a single function in Default_Iterator attribute
1669 -- has the proper type structure.
1671 function Check_Primitive_Function (Subp : Entity_Id) return Boolean;
1672 -- Common legality check for the previous two
1674 -----------------------------------
1675 -- Analyze_Stream_TSS_Definition --
1676 -----------------------------------
1678 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
1679 Subp : Entity_Id := Empty;
1684 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
1685 -- True for Read attribute, false for other attributes
1687 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
1688 -- Return true if the entity is a subprogram with an appropriate
1689 -- profile for the attribute being defined.
1691 ----------------------
1692 -- Has_Good_Profile --
1693 ----------------------
1695 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
1697 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
1698 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
1699 (False => E_Procedure, True => E_Function);
1703 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
1707 F := First_Formal (Subp);
1710 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
1711 or else Designated_Type (Etype (F)) /=
1712 Class_Wide_Type (RTE (RE_Root_Stream_Type))
1717 if not Is_Function then
1721 Expected_Mode : constant array (Boolean) of Entity_Kind :=
1722 (False => E_In_Parameter,
1723 True => E_Out_Parameter);
1725 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
1733 Typ := Etype (Subp);
1736 return Base_Type (Typ) = Base_Type (Ent)
1737 and then No (Next_Formal (F));
1738 end Has_Good_Profile;
1740 -- Start of processing for Analyze_Stream_TSS_Definition
1745 if not Is_Type (U_Ent) then
1746 Error_Msg_N ("local name must be a subtype", Nam);
1750 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
1752 -- If Pnam is present, it can be either inherited from an ancestor
1753 -- type (in which case it is legal to redefine it for this type), or
1754 -- be a previous definition of the attribute for the same type (in
1755 -- which case it is illegal).
1757 -- In the first case, it will have been analyzed already, and we
1758 -- can check that its profile does not match the expected profile
1759 -- for a stream attribute of U_Ent. In the second case, either Pnam
1760 -- has been analyzed (and has the expected profile), or it has not
1761 -- been analyzed yet (case of a type that has not been frozen yet
1762 -- and for which the stream attribute has been set using Set_TSS).
1765 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
1767 Error_Msg_Sloc := Sloc (Pnam);
1768 Error_Msg_Name_1 := Attr;
1769 Error_Msg_N ("% attribute already defined #", Nam);
1775 if Is_Entity_Name (Expr) then
1776 if not Is_Overloaded (Expr) then
1777 if Has_Good_Profile (Entity (Expr)) then
1778 Subp := Entity (Expr);
1782 Get_First_Interp (Expr, I, It);
1783 while Present (It.Nam) loop
1784 if Has_Good_Profile (It.Nam) then
1789 Get_Next_Interp (I, It);
1794 if Present (Subp) then
1795 if Is_Abstract_Subprogram (Subp) then
1796 Error_Msg_N ("stream subprogram must not be abstract", Expr);
1800 Set_Entity (Expr, Subp);
1801 Set_Etype (Expr, Etype (Subp));
1803 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
1806 Error_Msg_Name_1 := Attr;
1807 Error_Msg_N ("incorrect expression for% attribute", Expr);
1809 end Analyze_Stream_TSS_Definition;
1811 ------------------------------
1812 -- Check_Indexing_Functions --
1813 ------------------------------
1815 procedure Check_Indexing_Functions is
1817 procedure Check_One_Function (Subp : Entity_Id);
1818 -- Check one possible interpretation
1820 ------------------------
1821 -- Check_One_Function --
1822 ------------------------
1824 procedure Check_One_Function (Subp : Entity_Id) is
1826 if not Check_Primitive_Function (Subp) then
1828 ("aspect Indexing requires a function that applies to type&",
1832 if not Has_Implicit_Dereference (Etype (Subp)) then
1834 ("function for indexing must return a reference type", Subp);
1836 end Check_One_Function;
1838 -- Start of processing for Check_Indexing_Functions
1847 if not Is_Overloaded (Expr) then
1848 Check_One_Function (Entity (Expr));
1856 Get_First_Interp (Expr, I, It);
1857 while Present (It.Nam) loop
1859 -- Note that analysis will have added the interpretation
1860 -- that corresponds to the dereference. We only check the
1861 -- subprogram itself.
1863 if Is_Overloadable (It.Nam) then
1864 Check_One_Function (It.Nam);
1867 Get_Next_Interp (I, It);
1871 end Check_Indexing_Functions;
1873 ------------------------------
1874 -- Check_Iterator_Functions --
1875 ------------------------------
1877 procedure Check_Iterator_Functions is
1878 Default : Entity_Id;
1880 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean;
1881 -- Check one possible interpretation for validity
1883 ----------------------------
1884 -- Valid_Default_Iterator --
1885 ----------------------------
1887 function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is
1891 if not Check_Primitive_Function (Subp) then
1894 Formal := First_Formal (Subp);
1897 -- False if any subsequent formal has no default expression
1899 Formal := Next_Formal (Formal);
1900 while Present (Formal) loop
1901 if No (Expression (Parent (Formal))) then
1905 Next_Formal (Formal);
1908 -- True if all subsequent formals have default expressions
1911 end Valid_Default_Iterator;
1913 -- Start of processing for Check_Iterator_Functions
1918 if not Is_Entity_Name (Expr) then
1919 Error_Msg_N ("aspect Iterator must be a function name", Expr);
1922 if not Is_Overloaded (Expr) then
1923 if not Check_Primitive_Function (Entity (Expr)) then
1925 ("aspect Indexing requires a function that applies to type&",
1926 Entity (Expr), Ent);
1929 if not Valid_Default_Iterator (Entity (Expr)) then
1930 Error_Msg_N ("improper function for default iterator", Expr);
1940 Get_First_Interp (Expr, I, It);
1941 while Present (It.Nam) loop
1942 if not Check_Primitive_Function (It.Nam)
1943 or else not Valid_Default_Iterator (It.Nam)
1947 elsif Present (Default) then
1948 Error_Msg_N ("default iterator must be unique", Expr);
1954 Get_Next_Interp (I, It);
1958 if Present (Default) then
1959 Set_Entity (Expr, Default);
1960 Set_Is_Overloaded (Expr, False);
1963 end Check_Iterator_Functions;
1965 -------------------------------
1966 -- Check_Primitive_Function --
1967 -------------------------------
1969 function Check_Primitive_Function (Subp : Entity_Id) return Boolean is
1973 if Ekind (Subp) /= E_Function then
1977 if No (First_Formal (Subp)) then
1980 Ctrl := Etype (First_Formal (Subp));
1984 or else Ctrl = Class_Wide_Type (Ent)
1986 (Ekind (Ctrl) = E_Anonymous_Access_Type
1988 (Designated_Type (Ctrl) = Ent
1989 or else Designated_Type (Ctrl) = Class_Wide_Type (Ent)))
1998 end Check_Primitive_Function;
2000 ----------------------
2001 -- Duplicate_Clause --
2002 ----------------------
2004 function Duplicate_Clause return Boolean is
2008 -- Nothing to do if this attribute definition clause comes from
2009 -- an aspect specification, since we could not be duplicating an
2010 -- explicit clause, and we dealt with the case of duplicated aspects
2011 -- in Analyze_Aspect_Specifications.
2013 if From_Aspect_Specification (N) then
2017 -- Otherwise current clause may duplicate previous clause or a
2018 -- previously given aspect specification for the same aspect.
2020 A := Get_Rep_Item_For_Entity (U_Ent, Chars (N));
2023 if Entity (A) = U_Ent then
2024 Error_Msg_Name_1 := Chars (N);
2025 Error_Msg_Sloc := Sloc (A);
2026 Error_Msg_NE ("aspect% for & previously given#", N, U_Ent);
2032 end Duplicate_Clause;
2034 -- Start of processing for Analyze_Attribute_Definition_Clause
2037 -- The following code is a defense against recursion. Not clear that
2038 -- this can happen legitimately, but perhaps some error situations
2039 -- can cause it, and we did see this recursion during testing.
2041 if Analyzed (N) then
2044 Set_Analyzed (N, True);
2047 -- Process Ignore_Rep_Clauses option (we also ignore rep clauses in
2048 -- CodePeer mode or Alfa mode, since they are not relevant in these
2051 if Ignore_Rep_Clauses or CodePeer_Mode or Alfa_Mode then
2054 -- The following should be ignored. They do not affect legality
2055 -- and may be target dependent. The basic idea of -gnatI is to
2056 -- ignore any rep clauses that may be target dependent but do not
2057 -- affect legality (except possibly to be rejected because they
2058 -- are incompatible with the compilation target).
2060 when Attribute_Alignment |
2061 Attribute_Bit_Order |
2062 Attribute_Component_Size |
2063 Attribute_Machine_Radix |
2064 Attribute_Object_Size |
2066 Attribute_Stream_Size |
2067 Attribute_Value_Size =>
2068 Rewrite (N, Make_Null_Statement (Sloc (N)));
2071 -- We do not want too ignore 'Small in CodePeer_Mode or Alfa_Mode,
2072 -- since it has an impact on the exact computations performed.
2074 -- Perhaps 'Small should also not be ignored by
2075 -- Ignore_Rep_Clauses ???
2077 when Attribute_Small =>
2078 if Ignore_Rep_Clauses then
2079 Rewrite (N, Make_Null_Statement (Sloc (N)));
2083 -- The following should not be ignored, because in the first place
2084 -- they are reasonably portable, and should not cause problems in
2085 -- compiling code from another target, and also they do affect
2086 -- legality, e.g. failing to provide a stream attribute for a
2087 -- type may make a program illegal.
2089 when Attribute_External_Tag |
2093 Attribute_Storage_Pool |
2094 Attribute_Storage_Size |
2098 -- Other cases are errors ("attribute& cannot be set with
2099 -- definition clause"), which will be caught below.
2107 Ent := Entity (Nam);
2109 if Rep_Item_Too_Early (Ent, N) then
2113 -- Rep clause applies to full view of incomplete type or private type if
2114 -- we have one (if not, this is a premature use of the type). However,
2115 -- certain semantic checks need to be done on the specified entity (i.e.
2116 -- the private view), so we save it in Ent.
2118 if Is_Private_Type (Ent)
2119 and then Is_Derived_Type (Ent)
2120 and then not Is_Tagged_Type (Ent)
2121 and then No (Full_View (Ent))
2123 -- If this is a private type whose completion is a derivation from
2124 -- another private type, there is no full view, and the attribute
2125 -- belongs to the type itself, not its underlying parent.
2129 elsif Ekind (Ent) = E_Incomplete_Type then
2131 -- The attribute applies to the full view, set the entity of the
2132 -- attribute definition accordingly.
2134 Ent := Underlying_Type (Ent);
2136 Set_Entity (Nam, Ent);
2139 U_Ent := Underlying_Type (Ent);
2142 -- Complete other routine error checks
2144 if Etype (Nam) = Any_Type then
2147 elsif Scope (Ent) /= Current_Scope then
2148 Error_Msg_N ("entity must be declared in this scope", Nam);
2151 elsif No (U_Ent) then
2154 elsif Is_Type (U_Ent)
2155 and then not Is_First_Subtype (U_Ent)
2156 and then Id /= Attribute_Object_Size
2157 and then Id /= Attribute_Value_Size
2158 and then not From_At_Mod (N)
2160 Error_Msg_N ("cannot specify attribute for subtype", Nam);
2164 Set_Entity (N, U_Ent);
2166 -- Switch on particular attribute
2174 -- Address attribute definition clause
2176 when Attribute_Address => Address : begin
2178 -- A little error check, catch for X'Address use X'Address;
2180 if Nkind (Nam) = N_Identifier
2181 and then Nkind (Expr) = N_Attribute_Reference
2182 and then Attribute_Name (Expr) = Name_Address
2183 and then Nkind (Prefix (Expr)) = N_Identifier
2184 and then Chars (Nam) = Chars (Prefix (Expr))
2187 ("address for & is self-referencing", Prefix (Expr), Ent);
2191 -- Not that special case, carry on with analysis of expression
2193 Analyze_And_Resolve (Expr, RTE (RE_Address));
2195 -- Even when ignoring rep clauses we need to indicate that the
2196 -- entity has an address clause and thus it is legal to declare
2199 if Ignore_Rep_Clauses then
2200 if Ekind_In (U_Ent, E_Variable, E_Constant) then
2201 Record_Rep_Item (U_Ent, N);
2207 if Duplicate_Clause then
2210 -- Case of address clause for subprogram
2212 elsif Is_Subprogram (U_Ent) then
2213 if Has_Homonym (U_Ent) then
2215 ("address clause cannot be given " &
2216 "for overloaded subprogram",
2221 -- For subprograms, all address clauses are permitted, and we
2222 -- mark the subprogram as having a deferred freeze so that Gigi
2223 -- will not elaborate it too soon.
2225 -- Above needs more comments, what is too soon about???
2227 Set_Has_Delayed_Freeze (U_Ent);
2229 -- Case of address clause for entry
2231 elsif Ekind (U_Ent) = E_Entry then
2232 if Nkind (Parent (N)) = N_Task_Body then
2234 ("entry address must be specified in task spec", Nam);
2238 -- For entries, we require a constant address
2240 Check_Constant_Address_Clause (Expr, U_Ent);
2242 -- Special checks for task types
2244 if Is_Task_Type (Scope (U_Ent))
2245 and then Comes_From_Source (Scope (U_Ent))
2248 ("?entry address declared for entry in task type", N);
2250 ("\?only one task can be declared of this type", N);
2253 -- Entry address clauses are obsolescent
2255 Check_Restriction (No_Obsolescent_Features, N);
2257 if Warn_On_Obsolescent_Feature then
2259 ("attaching interrupt to task entry is an " &
2260 "obsolescent feature (RM J.7.1)?", N);
2262 ("\use interrupt procedure instead?", N);
2265 -- Case of an address clause for a controlled object which we
2266 -- consider to be erroneous.
2268 elsif Is_Controlled (Etype (U_Ent))
2269 or else Has_Controlled_Component (Etype (U_Ent))
2272 ("?controlled object& must not be overlaid", Nam, U_Ent);
2274 ("\?Program_Error will be raised at run time", Nam);
2275 Insert_Action (Declaration_Node (U_Ent),
2276 Make_Raise_Program_Error (Loc,
2277 Reason => PE_Overlaid_Controlled_Object));
2280 -- Case of address clause for a (non-controlled) object
2283 Ekind (U_Ent) = E_Variable
2285 Ekind (U_Ent) = E_Constant
2288 Expr : constant Node_Id := Expression (N);
2293 -- Exported variables cannot have an address clause, because
2294 -- this cancels the effect of the pragma Export.
2296 if Is_Exported (U_Ent) then
2298 ("cannot export object with address clause", Nam);
2302 Find_Overlaid_Entity (N, O_Ent, Off);
2304 -- Overlaying controlled objects is erroneous
2307 and then (Has_Controlled_Component (Etype (O_Ent))
2308 or else Is_Controlled (Etype (O_Ent)))
2311 ("?cannot overlay with controlled object", Expr);
2313 ("\?Program_Error will be raised at run time", Expr);
2314 Insert_Action (Declaration_Node (U_Ent),
2315 Make_Raise_Program_Error (Loc,
2316 Reason => PE_Overlaid_Controlled_Object));
2319 elsif Present (O_Ent)
2320 and then Ekind (U_Ent) = E_Constant
2321 and then not Is_Constant_Object (O_Ent)
2323 Error_Msg_N ("constant overlays a variable?", Expr);
2325 elsif Present (Renamed_Object (U_Ent)) then
2327 ("address clause not allowed"
2328 & " for a renaming declaration (RM 13.1(6))", Nam);
2331 -- Imported variables can have an address clause, but then
2332 -- the import is pretty meaningless except to suppress
2333 -- initializations, so we do not need such variables to
2334 -- be statically allocated (and in fact it causes trouble
2335 -- if the address clause is a local value).
2337 elsif Is_Imported (U_Ent) then
2338 Set_Is_Statically_Allocated (U_Ent, False);
2341 -- We mark a possible modification of a variable with an
2342 -- address clause, since it is likely aliasing is occurring.
2344 Note_Possible_Modification (Nam, Sure => False);
2346 -- Here we are checking for explicit overlap of one variable
2347 -- by another, and if we find this then mark the overlapped
2348 -- variable as also being volatile to prevent unwanted
2349 -- optimizations. This is a significant pessimization so
2350 -- avoid it when there is an offset, i.e. when the object
2351 -- is composite; they cannot be optimized easily anyway.
2354 and then Is_Object (O_Ent)
2357 Set_Treat_As_Volatile (O_Ent);
2360 -- Legality checks on the address clause for initialized
2361 -- objects is deferred until the freeze point, because
2362 -- a subsequent pragma might indicate that the object is
2363 -- imported and thus not initialized.
2365 Set_Has_Delayed_Freeze (U_Ent);
2367 -- If an initialization call has been generated for this
2368 -- object, it needs to be deferred to after the freeze node
2369 -- we have just now added, otherwise GIGI will see a
2370 -- reference to the variable (as actual to the IP call)
2371 -- before its definition.
2374 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
2376 if Present (Init_Call) then
2378 Append_Freeze_Action (U_Ent, Init_Call);
2382 if Is_Exported (U_Ent) then
2384 ("& cannot be exported if an address clause is given",
2387 ("\define and export a variable " &
2388 "that holds its address instead",
2392 -- Entity has delayed freeze, so we will generate an
2393 -- alignment check at the freeze point unless suppressed.
2395 if not Range_Checks_Suppressed (U_Ent)
2396 and then not Alignment_Checks_Suppressed (U_Ent)
2398 Set_Check_Address_Alignment (N);
2401 -- Kill the size check code, since we are not allocating
2402 -- the variable, it is somewhere else.
2404 Kill_Size_Check_Code (U_Ent);
2406 -- If the address clause is of the form:
2408 -- for Y'Address use X'Address
2412 -- Const : constant Address := X'Address;
2414 -- for Y'Address use Const;
2416 -- then we make an entry in the table for checking the size
2417 -- and alignment of the overlaying variable. We defer this
2418 -- check till after code generation to take full advantage
2419 -- of the annotation done by the back end. This entry is
2420 -- only made if the address clause comes from source.
2422 -- If the entity has a generic type, the check will be
2423 -- performed in the instance if the actual type justifies
2424 -- it, and we do not insert the clause in the table to
2425 -- prevent spurious warnings.
2427 if Address_Clause_Overlay_Warnings
2428 and then Comes_From_Source (N)
2429 and then Present (O_Ent)
2430 and then Is_Object (O_Ent)
2432 if not Is_Generic_Type (Etype (U_Ent)) then
2433 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
2436 -- If variable overlays a constant view, and we are
2437 -- warning on overlays, then mark the variable as
2438 -- overlaying a constant (we will give warnings later
2439 -- if this variable is assigned).
2441 if Is_Constant_Object (O_Ent)
2442 and then Ekind (U_Ent) = E_Variable
2444 Set_Overlays_Constant (U_Ent);
2449 -- Not a valid entity for an address clause
2452 Error_Msg_N ("address cannot be given for &", Nam);
2460 -- Alignment attribute definition clause
2462 when Attribute_Alignment => Alignment : declare
2463 Align : constant Uint := Get_Alignment_Value (Expr);
2468 if not Is_Type (U_Ent)
2469 and then Ekind (U_Ent) /= E_Variable
2470 and then Ekind (U_Ent) /= E_Constant
2472 Error_Msg_N ("alignment cannot be given for &", Nam);
2474 elsif Duplicate_Clause then
2477 elsif Align /= No_Uint then
2478 Set_Has_Alignment_Clause (U_Ent);
2479 Set_Alignment (U_Ent, Align);
2481 -- For an array type, U_Ent is the first subtype. In that case,
2482 -- also set the alignment of the anonymous base type so that
2483 -- other subtypes (such as the itypes for aggregates of the
2484 -- type) also receive the expected alignment.
2486 if Is_Array_Type (U_Ent) then
2487 Set_Alignment (Base_Type (U_Ent), Align);
2496 -- Bit_Order attribute definition clause
2498 when Attribute_Bit_Order => Bit_Order : declare
2500 if not Is_Record_Type (U_Ent) then
2502 ("Bit_Order can only be defined for record type", Nam);
2504 elsif Duplicate_Clause then
2508 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
2510 if Etype (Expr) = Any_Type then
2513 elsif not Is_Static_Expression (Expr) then
2514 Flag_Non_Static_Expr
2515 ("Bit_Order requires static expression!", Expr);
2518 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
2519 Set_Reverse_Bit_Order (U_Ent, True);
2525 --------------------
2526 -- Component_Size --
2527 --------------------
2529 -- Component_Size attribute definition clause
2531 when Attribute_Component_Size => Component_Size_Case : declare
2532 Csize : constant Uint := Static_Integer (Expr);
2536 New_Ctyp : Entity_Id;
2540 if not Is_Array_Type (U_Ent) then
2541 Error_Msg_N ("component size requires array type", Nam);
2545 Btype := Base_Type (U_Ent);
2546 Ctyp := Component_Type (Btype);
2548 if Duplicate_Clause then
2551 elsif Rep_Item_Too_Early (Btype, N) then
2554 elsif Csize /= No_Uint then
2555 Check_Size (Expr, Ctyp, Csize, Biased);
2557 -- For the biased case, build a declaration for a subtype that
2558 -- will be used to represent the biased subtype that reflects
2559 -- the biased representation of components. We need the subtype
2560 -- to get proper conversions on referencing elements of the
2561 -- array. Note: component size clauses are ignored in VM mode.
2563 if VM_Target = No_VM then
2566 Make_Defining_Identifier (Loc,
2568 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
2571 Make_Subtype_Declaration (Loc,
2572 Defining_Identifier => New_Ctyp,
2573 Subtype_Indication =>
2574 New_Occurrence_Of (Component_Type (Btype), Loc));
2576 Set_Parent (Decl, N);
2577 Analyze (Decl, Suppress => All_Checks);
2579 Set_Has_Delayed_Freeze (New_Ctyp, False);
2580 Set_Esize (New_Ctyp, Csize);
2581 Set_RM_Size (New_Ctyp, Csize);
2582 Init_Alignment (New_Ctyp);
2583 Set_Is_Itype (New_Ctyp, True);
2584 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
2586 Set_Component_Type (Btype, New_Ctyp);
2587 Set_Biased (New_Ctyp, N, "component size clause");
2590 Set_Component_Size (Btype, Csize);
2592 -- For VM case, we ignore component size clauses
2595 -- Give a warning unless we are in GNAT mode, in which case
2596 -- the warning is suppressed since it is not useful.
2598 if not GNAT_Mode then
2600 ("?component size ignored in this configuration", N);
2604 -- Deal with warning on overridden size
2606 if Warn_On_Overridden_Size
2607 and then Has_Size_Clause (Ctyp)
2608 and then RM_Size (Ctyp) /= Csize
2611 ("?component size overrides size clause for&",
2615 Set_Has_Component_Size_Clause (Btype, True);
2616 Set_Has_Non_Standard_Rep (Btype, True);
2618 end Component_Size_Case;
2620 -----------------------
2621 -- Constant_Indexing --
2622 -----------------------
2624 when Attribute_Constant_Indexing =>
2625 Check_Indexing_Functions;
2627 ----------------------
2628 -- Default_Iterator --
2629 ----------------------
2631 when Attribute_Default_Iterator => Default_Iterator : declare
2635 if not Is_Tagged_Type (U_Ent) then
2637 ("aspect Default_Iterator applies to tagged type", Nam);
2640 Check_Iterator_Functions;
2644 if not Is_Entity_Name (Expr)
2645 or else Ekind (Entity (Expr)) /= E_Function
2647 Error_Msg_N ("aspect Iterator must be a function", Expr);
2649 Func := Entity (Expr);
2652 if No (First_Formal (Func))
2653 or else Etype (First_Formal (Func)) /= U_Ent
2656 ("Default Iterator must be a primitive of&", Func, U_Ent);
2658 end Default_Iterator;
2664 when Attribute_External_Tag => External_Tag :
2666 if not Is_Tagged_Type (U_Ent) then
2667 Error_Msg_N ("should be a tagged type", Nam);
2670 if Duplicate_Clause then
2674 Analyze_And_Resolve (Expr, Standard_String);
2676 if not Is_Static_Expression (Expr) then
2677 Flag_Non_Static_Expr
2678 ("static string required for tag name!", Nam);
2681 if VM_Target = No_VM then
2682 Set_Has_External_Tag_Rep_Clause (U_Ent);
2684 Error_Msg_Name_1 := Attr;
2686 ("% attribute unsupported in this configuration", Nam);
2689 if not Is_Library_Level_Entity (U_Ent) then
2691 ("?non-unique external tag supplied for &", N, U_Ent);
2693 ("?\same external tag applies to all subprogram calls", N);
2695 ("?\corresponding internal tag cannot be obtained", N);
2700 --------------------------
2701 -- Implicit_Dereference --
2702 --------------------------
2704 when Attribute_Implicit_Dereference =>
2706 -- Legality checks already performed at the point of
2707 -- the type declaration, aspect is not delayed.
2715 when Attribute_Input =>
2716 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
2717 Set_Has_Specified_Stream_Input (Ent);
2719 ----------------------
2720 -- Iterator_Element --
2721 ----------------------
2723 when Attribute_Iterator_Element =>
2726 if not Is_Entity_Name (Expr)
2727 or else not Is_Type (Entity (Expr))
2729 Error_Msg_N ("aspect Iterator_Element must be a type", Expr);
2736 -- Machine radix attribute definition clause
2738 when Attribute_Machine_Radix => Machine_Radix : declare
2739 Radix : constant Uint := Static_Integer (Expr);
2742 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
2743 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
2745 elsif Duplicate_Clause then
2748 elsif Radix /= No_Uint then
2749 Set_Has_Machine_Radix_Clause (U_Ent);
2750 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
2754 elsif Radix = 10 then
2755 Set_Machine_Radix_10 (U_Ent);
2757 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
2766 -- Object_Size attribute definition clause
2768 when Attribute_Object_Size => Object_Size : declare
2769 Size : constant Uint := Static_Integer (Expr);
2772 pragma Warnings (Off, Biased);
2775 if not Is_Type (U_Ent) then
2776 Error_Msg_N ("Object_Size cannot be given for &", Nam);
2778 elsif Duplicate_Clause then
2782 Check_Size (Expr, U_Ent, Size, Biased);
2790 UI_Mod (Size, 64) /= 0
2793 ("Object_Size must be 8, 16, 32, or multiple of 64",
2797 Set_Esize (U_Ent, Size);
2798 Set_Has_Object_Size_Clause (U_Ent);
2799 Alignment_Check_For_Size_Change (U_Ent, Size);
2807 when Attribute_Output =>
2808 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
2809 Set_Has_Specified_Stream_Output (Ent);
2815 when Attribute_Read =>
2816 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
2817 Set_Has_Specified_Stream_Read (Ent);
2823 -- Size attribute definition clause
2825 when Attribute_Size => Size : declare
2826 Size : constant Uint := Static_Integer (Expr);
2833 if Duplicate_Clause then
2836 elsif not Is_Type (U_Ent)
2837 and then Ekind (U_Ent) /= E_Variable
2838 and then Ekind (U_Ent) /= E_Constant
2840 Error_Msg_N ("size cannot be given for &", Nam);
2842 elsif Is_Array_Type (U_Ent)
2843 and then not Is_Constrained (U_Ent)
2846 ("size cannot be given for unconstrained array", Nam);
2848 elsif Size /= No_Uint then
2849 if VM_Target /= No_VM and then not GNAT_Mode then
2851 -- Size clause is not handled properly on VM targets.
2852 -- Display a warning unless we are in GNAT mode, in which
2853 -- case this is useless.
2856 ("?size clauses are ignored in this configuration", N);
2859 if Is_Type (U_Ent) then
2862 Etyp := Etype (U_Ent);
2865 -- Check size, note that Gigi is in charge of checking that the
2866 -- size of an array or record type is OK. Also we do not check
2867 -- the size in the ordinary fixed-point case, since it is too
2868 -- early to do so (there may be subsequent small clause that
2869 -- affects the size). We can check the size if a small clause
2870 -- has already been given.
2872 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
2873 or else Has_Small_Clause (U_Ent)
2875 Check_Size (Expr, Etyp, Size, Biased);
2876 Set_Biased (U_Ent, N, "size clause", Biased);
2879 -- For types set RM_Size and Esize if possible
2881 if Is_Type (U_Ent) then
2882 Set_RM_Size (U_Ent, Size);
2884 -- For elementary types, increase Object_Size to power of 2,
2885 -- but not less than a storage unit in any case (normally
2886 -- this means it will be byte addressable).
2888 -- For all other types, nothing else to do, we leave Esize
2889 -- (object size) unset, the back end will set it from the
2890 -- size and alignment in an appropriate manner.
2892 -- In both cases, we check whether the alignment must be
2893 -- reset in the wake of the size change.
2895 if Is_Elementary_Type (U_Ent) then
2896 if Size <= System_Storage_Unit then
2897 Init_Esize (U_Ent, System_Storage_Unit);
2898 elsif Size <= 16 then
2899 Init_Esize (U_Ent, 16);
2900 elsif Size <= 32 then
2901 Init_Esize (U_Ent, 32);
2903 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
2906 Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent));
2908 Alignment_Check_For_Size_Change (U_Ent, Size);
2911 -- For objects, set Esize only
2914 if Is_Elementary_Type (Etyp) then
2915 if Size /= System_Storage_Unit
2917 Size /= System_Storage_Unit * 2
2919 Size /= System_Storage_Unit * 4
2921 Size /= System_Storage_Unit * 8
2923 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
2924 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
2926 ("size for primitive object must be a power of 2"
2927 & " in the range ^-^", N);
2931 Set_Esize (U_Ent, Size);
2934 Set_Has_Size_Clause (U_Ent);
2942 -- Small attribute definition clause
2944 when Attribute_Small => Small : declare
2945 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
2949 Analyze_And_Resolve (Expr, Any_Real);
2951 if Etype (Expr) = Any_Type then
2954 elsif not Is_Static_Expression (Expr) then
2955 Flag_Non_Static_Expr
2956 ("small requires static expression!", Expr);
2960 Small := Expr_Value_R (Expr);
2962 if Small <= Ureal_0 then
2963 Error_Msg_N ("small value must be greater than zero", Expr);
2969 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
2971 ("small requires an ordinary fixed point type", Nam);
2973 elsif Has_Small_Clause (U_Ent) then
2974 Error_Msg_N ("small already given for &", Nam);
2976 elsif Small > Delta_Value (U_Ent) then
2978 ("small value must not be greater then delta value", Nam);
2981 Set_Small_Value (U_Ent, Small);
2982 Set_Small_Value (Implicit_Base, Small);
2983 Set_Has_Small_Clause (U_Ent);
2984 Set_Has_Small_Clause (Implicit_Base);
2985 Set_Has_Non_Standard_Rep (Implicit_Base);
2993 -- Storage_Pool attribute definition clause
2995 when Attribute_Storage_Pool => Storage_Pool : declare
3000 if Ekind (U_Ent) = E_Access_Subprogram_Type then
3002 ("storage pool cannot be given for access-to-subprogram type",
3007 Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type)
3010 ("storage pool can only be given for access types", Nam);
3013 elsif Is_Derived_Type (U_Ent) then
3015 ("storage pool cannot be given for a derived access type",
3018 elsif Duplicate_Clause then
3021 elsif Present (Associated_Storage_Pool (U_Ent)) then
3022 Error_Msg_N ("storage pool already given for &", Nam);
3027 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
3029 if not Denotes_Variable (Expr) then
3030 Error_Msg_N ("storage pool must be a variable", Expr);
3034 if Nkind (Expr) = N_Type_Conversion then
3035 T := Etype (Expression (Expr));
3040 -- The Stack_Bounded_Pool is used internally for implementing
3041 -- access types with a Storage_Size. Since it only work properly
3042 -- when used on one specific type, we need to check that it is not
3043 -- hijacked improperly:
3045 -- type T is access Integer;
3046 -- for T'Storage_Size use n;
3047 -- type Q is access Float;
3048 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
3050 if RTE_Available (RE_Stack_Bounded_Pool)
3051 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
3053 Error_Msg_N ("non-shareable internal Pool", Expr);
3057 -- If the argument is a name that is not an entity name, then
3058 -- we construct a renaming operation to define an entity of
3059 -- type storage pool.
3061 if not Is_Entity_Name (Expr)
3062 and then Is_Object_Reference (Expr)
3064 Pool := Make_Temporary (Loc, 'P', Expr);
3067 Rnode : constant Node_Id :=
3068 Make_Object_Renaming_Declaration (Loc,
3069 Defining_Identifier => Pool,
3071 New_Occurrence_Of (Etype (Expr), Loc),
3075 Insert_Before (N, Rnode);
3077 Set_Associated_Storage_Pool (U_Ent, Pool);
3080 elsif Is_Entity_Name (Expr) then
3081 Pool := Entity (Expr);
3083 -- If pool is a renamed object, get original one. This can
3084 -- happen with an explicit renaming, and within instances.
3086 while Present (Renamed_Object (Pool))
3087 and then Is_Entity_Name (Renamed_Object (Pool))
3089 Pool := Entity (Renamed_Object (Pool));
3092 if Present (Renamed_Object (Pool))
3093 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
3094 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
3096 Pool := Entity (Expression (Renamed_Object (Pool)));
3099 Set_Associated_Storage_Pool (U_Ent, Pool);
3101 elsif Nkind (Expr) = N_Type_Conversion
3102 and then Is_Entity_Name (Expression (Expr))
3103 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
3105 Pool := Entity (Expression (Expr));
3106 Set_Associated_Storage_Pool (U_Ent, Pool);
3109 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
3118 -- Storage_Size attribute definition clause
3120 when Attribute_Storage_Size => Storage_Size : declare
3121 Btype : constant Entity_Id := Base_Type (U_Ent);
3125 if Is_Task_Type (U_Ent) then
3126 Check_Restriction (No_Obsolescent_Features, N);
3128 if Warn_On_Obsolescent_Feature then
3130 ("storage size clause for task is an " &
3131 "obsolescent feature (RM J.9)?", N);
3132 Error_Msg_N ("\use Storage_Size pragma instead?", N);
3138 if not Is_Access_Type (U_Ent)
3139 and then Ekind (U_Ent) /= E_Task_Type
3141 Error_Msg_N ("storage size cannot be given for &", Nam);
3143 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
3145 ("storage size cannot be given for a derived access type",
3148 elsif Duplicate_Clause then
3152 Analyze_And_Resolve (Expr, Any_Integer);
3154 if Is_Access_Type (U_Ent) then
3155 if Present (Associated_Storage_Pool (U_Ent)) then
3156 Error_Msg_N ("storage pool already given for &", Nam);
3160 if Is_OK_Static_Expression (Expr)
3161 and then Expr_Value (Expr) = 0
3163 Set_No_Pool_Assigned (Btype);
3166 else -- Is_Task_Type (U_Ent)
3167 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
3169 if Present (Sprag) then
3170 Error_Msg_Sloc := Sloc (Sprag);
3172 ("Storage_Size already specified#", Nam);
3177 Set_Has_Storage_Size_Clause (Btype);
3185 when Attribute_Stream_Size => Stream_Size : declare
3186 Size : constant Uint := Static_Integer (Expr);
3189 if Ada_Version <= Ada_95 then
3190 Check_Restriction (No_Implementation_Attributes, N);
3193 if Duplicate_Clause then
3196 elsif Is_Elementary_Type (U_Ent) then
3197 if Size /= System_Storage_Unit
3199 Size /= System_Storage_Unit * 2
3201 Size /= System_Storage_Unit * 4
3203 Size /= System_Storage_Unit * 8
3205 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
3207 ("stream size for elementary type must be a"
3208 & " power of 2 and at least ^", N);
3210 elsif RM_Size (U_Ent) > Size then
3211 Error_Msg_Uint_1 := RM_Size (U_Ent);
3213 ("stream size for elementary type must be a"
3214 & " power of 2 and at least ^", N);
3217 Set_Has_Stream_Size_Clause (U_Ent);
3220 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
3228 -- Value_Size attribute definition clause
3230 when Attribute_Value_Size => Value_Size : declare
3231 Size : constant Uint := Static_Integer (Expr);
3235 if not Is_Type (U_Ent) then
3236 Error_Msg_N ("Value_Size cannot be given for &", Nam);
3238 elsif Duplicate_Clause then
3241 elsif Is_Array_Type (U_Ent)
3242 and then not Is_Constrained (U_Ent)
3245 ("Value_Size cannot be given for unconstrained array", Nam);
3248 if Is_Elementary_Type (U_Ent) then
3249 Check_Size (Expr, U_Ent, Size, Biased);
3250 Set_Biased (U_Ent, N, "value size clause", Biased);
3253 Set_RM_Size (U_Ent, Size);
3257 -----------------------
3258 -- Variable_Indexing --
3259 -----------------------
3261 when Attribute_Variable_Indexing =>
3262 Check_Indexing_Functions;
3268 when Attribute_Write =>
3269 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
3270 Set_Has_Specified_Stream_Write (Ent);
3272 -- All other attributes cannot be set
3276 ("attribute& cannot be set with definition clause", N);
3279 -- The test for the type being frozen must be performed after any
3280 -- expression the clause has been analyzed since the expression itself
3281 -- might cause freezing that makes the clause illegal.
3283 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
3286 end Analyze_Attribute_Definition_Clause;
3288 ----------------------------
3289 -- Analyze_Code_Statement --
3290 ----------------------------
3292 procedure Analyze_Code_Statement (N : Node_Id) is
3293 HSS : constant Node_Id := Parent (N);
3294 SBody : constant Node_Id := Parent (HSS);
3295 Subp : constant Entity_Id := Current_Scope;
3302 -- Analyze and check we get right type, note that this implements the
3303 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
3304 -- is the only way that Asm_Insn could possibly be visible.
3306 Analyze_And_Resolve (Expression (N));
3308 if Etype (Expression (N)) = Any_Type then
3310 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
3311 Error_Msg_N ("incorrect type for code statement", N);
3315 Check_Code_Statement (N);
3317 -- Make sure we appear in the handled statement sequence of a
3318 -- subprogram (RM 13.8(3)).
3320 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
3321 or else Nkind (SBody) /= N_Subprogram_Body
3324 ("code statement can only appear in body of subprogram", N);
3328 -- Do remaining checks (RM 13.8(3)) if not already done
3330 if not Is_Machine_Code_Subprogram (Subp) then
3331 Set_Is_Machine_Code_Subprogram (Subp);
3333 -- No exception handlers allowed
3335 if Present (Exception_Handlers (HSS)) then
3337 ("exception handlers not permitted in machine code subprogram",
3338 First (Exception_Handlers (HSS)));
3341 -- No declarations other than use clauses and pragmas (we allow
3342 -- certain internally generated declarations as well).
3344 Decl := First (Declarations (SBody));
3345 while Present (Decl) loop
3346 DeclO := Original_Node (Decl);
3347 if Comes_From_Source (DeclO)
3348 and not Nkind_In (DeclO, N_Pragma,
3349 N_Use_Package_Clause,
3351 N_Implicit_Label_Declaration)
3354 ("this declaration not allowed in machine code subprogram",
3361 -- No statements other than code statements, pragmas, and labels.
3362 -- Again we allow certain internally generated statements.
3364 Stmt := First (Statements (HSS));
3365 while Present (Stmt) loop
3366 StmtO := Original_Node (Stmt);
3367 if Comes_From_Source (StmtO)
3368 and then not Nkind_In (StmtO, N_Pragma,
3373 ("this statement is not allowed in machine code subprogram",
3380 end Analyze_Code_Statement;
3382 -----------------------------------------------
3383 -- Analyze_Enumeration_Representation_Clause --
3384 -----------------------------------------------
3386 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
3387 Ident : constant Node_Id := Identifier (N);
3388 Aggr : constant Node_Id := Array_Aggregate (N);
3389 Enumtype : Entity_Id;
3396 Err : Boolean := False;
3397 -- Set True to avoid cascade errors and crashes on incorrect source code
3399 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
3400 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
3401 -- Allowed range of universal integer (= allowed range of enum lit vals)
3405 -- Minimum and maximum values of entries
3408 -- Pointer to node for literal providing max value
3411 if Ignore_Rep_Clauses then
3415 -- First some basic error checks
3418 Enumtype := Entity (Ident);
3420 if Enumtype = Any_Type
3421 or else Rep_Item_Too_Early (Enumtype, N)
3425 Enumtype := Underlying_Type (Enumtype);
3428 if not Is_Enumeration_Type (Enumtype) then
3430 ("enumeration type required, found}",
3431 Ident, First_Subtype (Enumtype));
3435 -- Ignore rep clause on generic actual type. This will already have
3436 -- been flagged on the template as an error, and this is the safest
3437 -- way to ensure we don't get a junk cascaded message in the instance.
3439 if Is_Generic_Actual_Type (Enumtype) then
3442 -- Type must be in current scope
3444 elsif Scope (Enumtype) /= Current_Scope then
3445 Error_Msg_N ("type must be declared in this scope", Ident);
3448 -- Type must be a first subtype
3450 elsif not Is_First_Subtype (Enumtype) then
3451 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
3454 -- Ignore duplicate rep clause
3456 elsif Has_Enumeration_Rep_Clause (Enumtype) then
3457 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
3460 -- Don't allow rep clause for standard [wide_[wide_]]character
3462 elsif Is_Standard_Character_Type (Enumtype) then
3463 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
3466 -- Check that the expression is a proper aggregate (no parentheses)
3468 elsif Paren_Count (Aggr) /= 0 then
3470 ("extra parentheses surrounding aggregate not allowed",
3474 -- All tests passed, so set rep clause in place
3477 Set_Has_Enumeration_Rep_Clause (Enumtype);
3478 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
3481 -- Now we process the aggregate. Note that we don't use the normal
3482 -- aggregate code for this purpose, because we don't want any of the
3483 -- normal expansion activities, and a number of special semantic
3484 -- rules apply (including the component type being any integer type)
3486 Elit := First_Literal (Enumtype);
3488 -- First the positional entries if any
3490 if Present (Expressions (Aggr)) then
3491 Expr := First (Expressions (Aggr));
3492 while Present (Expr) loop
3494 Error_Msg_N ("too many entries in aggregate", Expr);
3498 Val := Static_Integer (Expr);
3500 -- Err signals that we found some incorrect entries processing
3501 -- the list. The final checks for completeness and ordering are
3502 -- skipped in this case.
3504 if Val = No_Uint then
3506 elsif Val < Lo or else Hi < Val then
3507 Error_Msg_N ("value outside permitted range", Expr);
3511 Set_Enumeration_Rep (Elit, Val);
3512 Set_Enumeration_Rep_Expr (Elit, Expr);
3518 -- Now process the named entries if present
3520 if Present (Component_Associations (Aggr)) then
3521 Assoc := First (Component_Associations (Aggr));
3522 while Present (Assoc) loop
3523 Choice := First (Choices (Assoc));
3525 if Present (Next (Choice)) then
3527 ("multiple choice not allowed here", Next (Choice));
3531 if Nkind (Choice) = N_Others_Choice then
3532 Error_Msg_N ("others choice not allowed here", Choice);
3535 elsif Nkind (Choice) = N_Range then
3537 -- ??? should allow zero/one element range here
3539 Error_Msg_N ("range not allowed here", Choice);
3543 Analyze_And_Resolve (Choice, Enumtype);
3545 if Error_Posted (Choice) then
3550 if Is_Entity_Name (Choice)
3551 and then Is_Type (Entity (Choice))
3553 Error_Msg_N ("subtype name not allowed here", Choice);
3556 -- ??? should allow static subtype with zero/one entry
3558 elsif Etype (Choice) = Base_Type (Enumtype) then
3559 if not Is_Static_Expression (Choice) then
3560 Flag_Non_Static_Expr
3561 ("non-static expression used for choice!", Choice);
3565 Elit := Expr_Value_E (Choice);
3567 if Present (Enumeration_Rep_Expr (Elit)) then
3569 Sloc (Enumeration_Rep_Expr (Elit));
3571 ("representation for& previously given#",
3576 Set_Enumeration_Rep_Expr (Elit, Expression (Assoc));
3578 Expr := Expression (Assoc);
3579 Val := Static_Integer (Expr);
3581 if Val = No_Uint then
3584 elsif Val < Lo or else Hi < Val then
3585 Error_Msg_N ("value outside permitted range", Expr);
3589 Set_Enumeration_Rep (Elit, Val);
3599 -- Aggregate is fully processed. Now we check that a full set of
3600 -- representations was given, and that they are in range and in order.
3601 -- These checks are only done if no other errors occurred.
3607 Elit := First_Literal (Enumtype);
3608 while Present (Elit) loop
3609 if No (Enumeration_Rep_Expr (Elit)) then
3610 Error_Msg_NE ("missing representation for&!", N, Elit);
3613 Val := Enumeration_Rep (Elit);
3615 if Min = No_Uint then
3619 if Val /= No_Uint then
3620 if Max /= No_Uint and then Val <= Max then
3622 ("enumeration value for& not ordered!",
3623 Enumeration_Rep_Expr (Elit), Elit);
3626 Max_Node := Enumeration_Rep_Expr (Elit);
3630 -- If there is at least one literal whose representation is not
3631 -- equal to the Pos value, then note that this enumeration type
3632 -- has a non-standard representation.
3634 if Val /= Enumeration_Pos (Elit) then
3635 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
3642 -- Now set proper size information
3645 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
3648 if Has_Size_Clause (Enumtype) then
3650 -- All OK, if size is OK now
3652 if RM_Size (Enumtype) >= Minsize then
3656 -- Try if we can get by with biasing
3659 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
3661 -- Error message if even biasing does not work
3663 if RM_Size (Enumtype) < Minsize then
3664 Error_Msg_Uint_1 := RM_Size (Enumtype);
3665 Error_Msg_Uint_2 := Max;
3667 ("previously given size (^) is too small "
3668 & "for this value (^)", Max_Node);
3670 -- If biasing worked, indicate that we now have biased rep
3674 (Enumtype, Size_Clause (Enumtype), "size clause");
3679 Set_RM_Size (Enumtype, Minsize);
3680 Set_Enum_Esize (Enumtype);
3683 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
3684 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
3685 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
3689 -- We repeat the too late test in case it froze itself!
3691 if Rep_Item_Too_Late (Enumtype, N) then
3694 end Analyze_Enumeration_Representation_Clause;
3696 ----------------------------
3697 -- Analyze_Free_Statement --
3698 ----------------------------
3700 procedure Analyze_Free_Statement (N : Node_Id) is
3702 Analyze (Expression (N));
3703 end Analyze_Free_Statement;
3705 ---------------------------
3706 -- Analyze_Freeze_Entity --
3707 ---------------------------
3709 procedure Analyze_Freeze_Entity (N : Node_Id) is
3710 E : constant Entity_Id := Entity (N);
3713 -- Remember that we are processing a freezing entity. Required to
3714 -- ensure correct decoration of internal entities associated with
3715 -- interfaces (see New_Overloaded_Entity).
3717 Inside_Freezing_Actions := Inside_Freezing_Actions + 1;
3719 -- For tagged types covering interfaces add internal entities that link
3720 -- the primitives of the interfaces with the primitives that cover them.
3721 -- Note: These entities were originally generated only when generating
3722 -- code because their main purpose was to provide support to initialize
3723 -- the secondary dispatch tables. They are now generated also when
3724 -- compiling with no code generation to provide ASIS the relationship
3725 -- between interface primitives and tagged type primitives. They are
3726 -- also used to locate primitives covering interfaces when processing
3727 -- generics (see Derive_Subprograms).
3729 if Ada_Version >= Ada_2005
3730 and then Ekind (E) = E_Record_Type
3731 and then Is_Tagged_Type (E)
3732 and then not Is_Interface (E)
3733 and then Has_Interfaces (E)
3735 -- This would be a good common place to call the routine that checks
3736 -- overriding of interface primitives (and thus factorize calls to
3737 -- Check_Abstract_Overriding located at different contexts in the
3738 -- compiler). However, this is not possible because it causes
3739 -- spurious errors in case of late overriding.
3741 Add_Internal_Interface_Entities (E);
3746 if Ekind (E) = E_Record_Type
3747 and then Is_CPP_Class (E)
3748 and then Is_Tagged_Type (E)
3749 and then Tagged_Type_Expansion
3750 and then Expander_Active
3752 if CPP_Num_Prims (E) = 0 then
3754 -- If the CPP type has user defined components then it must import
3755 -- primitives from C++. This is required because if the C++ class
3756 -- has no primitives then the C++ compiler does not added the _tag
3757 -- component to the type.
3759 pragma Assert (Chars (First_Entity (E)) = Name_uTag);
3761 if First_Entity (E) /= Last_Entity (E) then
3763 ("?'C'P'P type must import at least one primitive from C++",
3768 -- Check that all its primitives are abstract or imported from C++.
3769 -- Check also availability of the C++ constructor.
3772 Has_Constructors : constant Boolean := Has_CPP_Constructors (E);
3774 Error_Reported : Boolean := False;
3778 Elmt := First_Elmt (Primitive_Operations (E));
3779 while Present (Elmt) loop
3780 Prim := Node (Elmt);
3782 if Comes_From_Source (Prim) then
3783 if Is_Abstract_Subprogram (Prim) then
3786 elsif not Is_Imported (Prim)
3787 or else Convention (Prim) /= Convention_CPP
3790 ("?primitives of 'C'P'P types must be imported from C++"
3791 & " or abstract", Prim);
3793 elsif not Has_Constructors
3794 and then not Error_Reported
3796 Error_Msg_Name_1 := Chars (E);
3798 ("?'C'P'P constructor required for type %", Prim);
3799 Error_Reported := True;
3808 Inside_Freezing_Actions := Inside_Freezing_Actions - 1;
3810 -- If we have a type with predicates, build predicate function
3812 if Is_Type (E) and then Has_Predicates (E) then
3813 Build_Predicate_Function (E, N);
3816 -- If type has delayed aspects, this is where we do the preanalysis at
3817 -- the freeze point, as part of the consistent visibility check. Note
3818 -- that this must be done after calling Build_Predicate_Function or
3819 -- Build_Invariant_Procedure since these subprograms fix occurrences of
3820 -- the subtype name in the saved expression so that they will not cause
3821 -- trouble in the preanalysis.
3823 if Has_Delayed_Aspects (E) then
3828 -- Look for aspect specification entries for this entity
3830 Ritem := First_Rep_Item (E);
3831 while Present (Ritem) loop
3832 if Nkind (Ritem) = N_Aspect_Specification
3833 and then Entity (Ritem) = E
3834 and then Is_Delayed_Aspect (Ritem)
3835 and then Scope (E) = Current_Scope
3837 Check_Aspect_At_Freeze_Point (Ritem);
3840 Next_Rep_Item (Ritem);
3844 end Analyze_Freeze_Entity;
3846 ------------------------------------------
3847 -- Analyze_Record_Representation_Clause --
3848 ------------------------------------------
3850 -- Note: we check as much as we can here, but we can't do any checks
3851 -- based on the position values (e.g. overlap checks) until freeze time
3852 -- because especially in Ada 2005 (machine scalar mode), the processing
3853 -- for non-standard bit order can substantially change the positions.
3854 -- See procedure Check_Record_Representation_Clause (called from Freeze)
3855 -- for the remainder of this processing.
3857 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
3858 Ident : constant Node_Id := Identifier (N);
3863 Hbit : Uint := Uint_0;
3867 Rectype : Entity_Id;
3869 CR_Pragma : Node_Id := Empty;
3870 -- Points to N_Pragma node if Complete_Representation pragma present
3873 if Ignore_Rep_Clauses then
3878 Rectype := Entity (Ident);
3880 if Rectype = Any_Type
3881 or else Rep_Item_Too_Early (Rectype, N)
3885 Rectype := Underlying_Type (Rectype);
3888 -- First some basic error checks
3890 if not Is_Record_Type (Rectype) then
3892 ("record type required, found}", Ident, First_Subtype (Rectype));
3895 elsif Scope (Rectype) /= Current_Scope then
3896 Error_Msg_N ("type must be declared in this scope", N);
3899 elsif not Is_First_Subtype (Rectype) then
3900 Error_Msg_N ("cannot give record rep clause for subtype", N);
3903 elsif Has_Record_Rep_Clause (Rectype) then
3904 Error_Msg_N ("duplicate record rep clause ignored", N);
3907 elsif Rep_Item_Too_Late (Rectype, N) then
3911 if Present (Mod_Clause (N)) then
3913 Loc : constant Source_Ptr := Sloc (N);
3914 M : constant Node_Id := Mod_Clause (N);
3915 P : constant List_Id := Pragmas_Before (M);
3919 pragma Warnings (Off, Mod_Val);
3922 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
3924 if Warn_On_Obsolescent_Feature then
3926 ("mod clause is an obsolescent feature (RM J.8)?", N);
3928 ("\use alignment attribute definition clause instead?", N);
3935 -- In ASIS_Mode mode, expansion is disabled, but we must convert
3936 -- the Mod clause into an alignment clause anyway, so that the
3937 -- back-end can compute and back-annotate properly the size and
3938 -- alignment of types that may include this record.
3940 -- This seems dubious, this destroys the source tree in a manner
3941 -- not detectable by ASIS ???
3943 if Operating_Mode = Check_Semantics and then ASIS_Mode then
3945 Make_Attribute_Definition_Clause (Loc,
3946 Name => New_Reference_To (Base_Type (Rectype), Loc),
3947 Chars => Name_Alignment,
3948 Expression => Relocate_Node (Expression (M)));
3950 Set_From_At_Mod (AtM_Nod);
3951 Insert_After (N, AtM_Nod);
3952 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
3953 Set_Mod_Clause (N, Empty);
3956 -- Get the alignment value to perform error checking
3958 Mod_Val := Get_Alignment_Value (Expression (M));
3963 -- For untagged types, clear any existing component clauses for the
3964 -- type. If the type is derived, this is what allows us to override
3965 -- a rep clause for the parent. For type extensions, the representation
3966 -- of the inherited components is inherited, so we want to keep previous
3967 -- component clauses for completeness.
3969 if not Is_Tagged_Type (Rectype) then
3970 Comp := First_Component_Or_Discriminant (Rectype);
3971 while Present (Comp) loop
3972 Set_Component_Clause (Comp, Empty);
3973 Next_Component_Or_Discriminant (Comp);
3977 -- All done if no component clauses
3979 CC := First (Component_Clauses (N));
3985 -- A representation like this applies to the base type
3987 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
3988 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
3989 Set_Has_Specified_Layout (Base_Type (Rectype));
3991 -- Process the component clauses
3993 while Present (CC) loop
3997 if Nkind (CC) = N_Pragma then
4000 -- The only pragma of interest is Complete_Representation
4002 if Pragma_Name (CC) = Name_Complete_Representation then
4006 -- Processing for real component clause
4009 Posit := Static_Integer (Position (CC));
4010 Fbit := Static_Integer (First_Bit (CC));
4011 Lbit := Static_Integer (Last_Bit (CC));
4014 and then Fbit /= No_Uint
4015 and then Lbit /= No_Uint
4019 ("position cannot be negative", Position (CC));
4023 ("first bit cannot be negative", First_Bit (CC));
4025 -- The Last_Bit specified in a component clause must not be
4026 -- less than the First_Bit minus one (RM-13.5.1(10)).
4028 elsif Lbit < Fbit - 1 then
4030 ("last bit cannot be less than first bit minus one",
4033 -- Values look OK, so find the corresponding record component
4034 -- Even though the syntax allows an attribute reference for
4035 -- implementation-defined components, GNAT does not allow the
4036 -- tag to get an explicit position.
4038 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
4039 if Attribute_Name (Component_Name (CC)) = Name_Tag then
4040 Error_Msg_N ("position of tag cannot be specified", CC);
4042 Error_Msg_N ("illegal component name", CC);
4046 Comp := First_Entity (Rectype);
4047 while Present (Comp) loop
4048 exit when Chars (Comp) = Chars (Component_Name (CC));
4054 -- Maybe component of base type that is absent from
4055 -- statically constrained first subtype.
4057 Comp := First_Entity (Base_Type (Rectype));
4058 while Present (Comp) loop
4059 exit when Chars (Comp) = Chars (Component_Name (CC));
4066 ("component clause is for non-existent field", CC);
4068 -- Ada 2012 (AI05-0026): Any name that denotes a
4069 -- discriminant of an object of an unchecked union type
4070 -- shall not occur within a record_representation_clause.
4072 -- The general restriction of using record rep clauses on
4073 -- Unchecked_Union types has now been lifted. Since it is
4074 -- possible to introduce a record rep clause which mentions
4075 -- the discriminant of an Unchecked_Union in non-Ada 2012
4076 -- code, this check is applied to all versions of the
4079 elsif Ekind (Comp) = E_Discriminant
4080 and then Is_Unchecked_Union (Rectype)
4083 ("cannot reference discriminant of Unchecked_Union",
4084 Component_Name (CC));
4086 elsif Present (Component_Clause (Comp)) then
4088 -- Diagnose duplicate rep clause, or check consistency
4089 -- if this is an inherited component. In a double fault,
4090 -- there may be a duplicate inconsistent clause for an
4091 -- inherited component.
4093 if Scope (Original_Record_Component (Comp)) = Rectype
4094 or else Parent (Component_Clause (Comp)) = N
4096 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
4097 Error_Msg_N ("component clause previously given#", CC);
4101 Rep1 : constant Node_Id := Component_Clause (Comp);
4103 if Intval (Position (Rep1)) /=
4104 Intval (Position (CC))
4105 or else Intval (First_Bit (Rep1)) /=
4106 Intval (First_Bit (CC))
4107 or else Intval (Last_Bit (Rep1)) /=
4108 Intval (Last_Bit (CC))
4110 Error_Msg_N ("component clause inconsistent "
4111 & "with representation of ancestor", CC);
4112 elsif Warn_On_Redundant_Constructs then
4113 Error_Msg_N ("?redundant component clause "
4114 & "for inherited component!", CC);
4119 -- Normal case where this is the first component clause we
4120 -- have seen for this entity, so set it up properly.
4123 -- Make reference for field in record rep clause and set
4124 -- appropriate entity field in the field identifier.
4127 (Comp, Component_Name (CC), Set_Ref => False);
4128 Set_Entity (Component_Name (CC), Comp);
4130 -- Update Fbit and Lbit to the actual bit number
4132 Fbit := Fbit + UI_From_Int (SSU) * Posit;
4133 Lbit := Lbit + UI_From_Int (SSU) * Posit;
4135 if Has_Size_Clause (Rectype)
4136 and then RM_Size (Rectype) <= Lbit
4139 ("bit number out of range of specified size",
4142 Set_Component_Clause (Comp, CC);
4143 Set_Component_Bit_Offset (Comp, Fbit);
4144 Set_Esize (Comp, 1 + (Lbit - Fbit));
4145 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
4146 Set_Normalized_Position (Comp, Fbit / SSU);
4148 if Warn_On_Overridden_Size
4149 and then Has_Size_Clause (Etype (Comp))
4150 and then RM_Size (Etype (Comp)) /= Esize (Comp)
4153 ("?component size overrides size clause for&",
4154 Component_Name (CC), Etype (Comp));
4157 -- This information is also set in the corresponding
4158 -- component of the base type, found by accessing the
4159 -- Original_Record_Component link if it is present.
4161 Ocomp := Original_Record_Component (Comp);
4168 (Component_Name (CC),
4174 (Comp, First_Node (CC), "component clause", Biased);
4176 if Present (Ocomp) then
4177 Set_Component_Clause (Ocomp, CC);
4178 Set_Component_Bit_Offset (Ocomp, Fbit);
4179 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
4180 Set_Normalized_Position (Ocomp, Fbit / SSU);
4181 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
4183 Set_Normalized_Position_Max
4184 (Ocomp, Normalized_Position (Ocomp));
4186 -- Note: we don't use Set_Biased here, because we
4187 -- already gave a warning above if needed, and we
4188 -- would get a duplicate for the same name here.
4190 Set_Has_Biased_Representation
4191 (Ocomp, Has_Biased_Representation (Comp));
4194 if Esize (Comp) < 0 then
4195 Error_Msg_N ("component size is negative", CC);
4206 -- Check missing components if Complete_Representation pragma appeared
4208 if Present (CR_Pragma) then
4209 Comp := First_Component_Or_Discriminant (Rectype);
4210 while Present (Comp) loop
4211 if No (Component_Clause (Comp)) then
4213 ("missing component clause for &", CR_Pragma, Comp);
4216 Next_Component_Or_Discriminant (Comp);
4219 -- If no Complete_Representation pragma, warn if missing components
4221 elsif Warn_On_Unrepped_Components then
4223 Num_Repped_Components : Nat := 0;
4224 Num_Unrepped_Components : Nat := 0;
4227 -- First count number of repped and unrepped components
4229 Comp := First_Component_Or_Discriminant (Rectype);
4230 while Present (Comp) loop
4231 if Present (Component_Clause (Comp)) then
4232 Num_Repped_Components := Num_Repped_Components + 1;
4234 Num_Unrepped_Components := Num_Unrepped_Components + 1;
4237 Next_Component_Or_Discriminant (Comp);
4240 -- We are only interested in the case where there is at least one
4241 -- unrepped component, and at least half the components have rep
4242 -- clauses. We figure that if less than half have them, then the
4243 -- partial rep clause is really intentional. If the component
4244 -- type has no underlying type set at this point (as for a generic
4245 -- formal type), we don't know enough to give a warning on the
4248 if Num_Unrepped_Components > 0
4249 and then Num_Unrepped_Components < Num_Repped_Components
4251 Comp := First_Component_Or_Discriminant (Rectype);
4252 while Present (Comp) loop
4253 if No (Component_Clause (Comp))
4254 and then Comes_From_Source (Comp)
4255 and then Present (Underlying_Type (Etype (Comp)))
4256 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
4257 or else Size_Known_At_Compile_Time
4258 (Underlying_Type (Etype (Comp))))
4259 and then not Has_Warnings_Off (Rectype)
4261 Error_Msg_Sloc := Sloc (Comp);
4263 ("?no component clause given for & declared #",
4267 Next_Component_Or_Discriminant (Comp);
4272 end Analyze_Record_Representation_Clause;
4274 -------------------------------
4275 -- Build_Invariant_Procedure --
4276 -------------------------------
4278 -- The procedure that is constructed here has the form
4280 -- procedure typInvariant (Ixxx : typ) is
4282 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4283 -- pragma Check (Invariant, exp, "failed invariant from xxx");
4285 -- pragma Check (Invariant, exp, "failed inherited invariant from xxx");
4287 -- end typInvariant;
4289 procedure Build_Invariant_Procedure (Typ : Entity_Id; N : Node_Id) is
4290 Loc : constant Source_Ptr := Sloc (Typ);
4297 Visible_Decls : constant List_Id := Visible_Declarations (N);
4298 Private_Decls : constant List_Id := Private_Declarations (N);
4300 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean);
4301 -- Appends statements to Stmts for any invariants in the rep item chain
4302 -- of the given type. If Inherit is False, then we only process entries
4303 -- on the chain for the type Typ. If Inherit is True, then we ignore any
4304 -- Invariant aspects, but we process all Invariant'Class aspects, adding
4305 -- "inherited" to the exception message and generating an informational
4306 -- message about the inheritance of an invariant.
4308 Object_Name : constant Name_Id := New_Internal_Name ('I');
4309 -- Name for argument of invariant procedure
4311 Object_Entity : constant Node_Id :=
4312 Make_Defining_Identifier (Loc, Object_Name);
4313 -- The procedure declaration entity for the argument
4315 --------------------
4316 -- Add_Invariants --
4317 --------------------
4319 procedure Add_Invariants (T : Entity_Id; Inherit : Boolean) is
4329 procedure Replace_Type_Reference (N : Node_Id);
4330 -- Replace a single occurrence N of the subtype name with a reference
4331 -- to the formal of the predicate function. N can be an identifier
4332 -- referencing the subtype, or a selected component, representing an
4333 -- appropriately qualified occurrence of the subtype name.
4335 procedure Replace_Type_References is
4336 new Replace_Type_References_Generic (Replace_Type_Reference);
4337 -- Traverse an expression replacing all occurrences of the subtype
4338 -- name with appropriate references to the object that is the formal
4339 -- parameter of the predicate function. Note that we must ensure
4340 -- that the type and entity information is properly set in the
4341 -- replacement node, since we will do a Preanalyze call of this
4342 -- expression without proper visibility of the procedure argument.
4344 ----------------------------
4345 -- Replace_Type_Reference --
4346 ----------------------------
4348 procedure Replace_Type_Reference (N : Node_Id) is
4350 -- Invariant'Class, replace with T'Class (obj)
4352 if Class_Present (Ritem) then
4354 Make_Type_Conversion (Loc,
4356 Make_Attribute_Reference (Loc,
4357 Prefix => New_Occurrence_Of (T, Loc),
4358 Attribute_Name => Name_Class),
4359 Expression => Make_Identifier (Loc, Object_Name)));
4361 Set_Entity (Expression (N), Object_Entity);
4362 Set_Etype (Expression (N), Typ);
4364 -- Invariant, replace with obj
4367 Rewrite (N, Make_Identifier (Loc, Object_Name));
4368 Set_Entity (N, Object_Entity);
4371 end Replace_Type_Reference;
4373 -- Start of processing for Add_Invariants
4376 Ritem := First_Rep_Item (T);
4377 while Present (Ritem) loop
4378 if Nkind (Ritem) = N_Pragma
4379 and then Pragma_Name (Ritem) = Name_Invariant
4381 Arg1 := First (Pragma_Argument_Associations (Ritem));
4382 Arg2 := Next (Arg1);
4383 Arg3 := Next (Arg2);
4385 Arg1 := Get_Pragma_Arg (Arg1);
4386 Arg2 := Get_Pragma_Arg (Arg2);
4388 -- For Inherit case, ignore Invariant, process only Class case
4391 if not Class_Present (Ritem) then
4395 -- For Inherit false, process only item for right type
4398 if Entity (Arg1) /= Typ then
4404 Stmts := Empty_List;
4407 Exp := New_Copy_Tree (Arg2);
4410 -- We need to replace any occurrences of the name of the type
4411 -- with references to the object, converted to type'Class in
4412 -- the case of Invariant'Class aspects.
4414 Replace_Type_References (Exp, Chars (T));
4416 -- If this invariant comes from an aspect, find the aspect
4417 -- specification, and replace the saved expression because
4418 -- we need the subtype references replaced for the calls to
4419 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4420 -- and Check_Aspect_At_End_Of_Declarations.
4422 if From_Aspect_Specification (Ritem) then
4427 -- Loop to find corresponding aspect, note that this
4428 -- must be present given the pragma is marked delayed.
4430 Aitem := Next_Rep_Item (Ritem);
4431 while Present (Aitem) loop
4432 if Nkind (Aitem) = N_Aspect_Specification
4433 and then Aspect_Rep_Item (Aitem) = Ritem
4436 (Identifier (Aitem), New_Copy_Tree (Exp));
4440 Aitem := Next_Rep_Item (Aitem);
4445 -- Now we need to preanalyze the expression to properly capture
4446 -- the visibility in the visible part. The expression will not
4447 -- be analyzed for real until the body is analyzed, but that is
4448 -- at the end of the private part and has the wrong visibility.
4450 Set_Parent (Exp, N);
4451 Preanalyze_Spec_Expression (Exp, Standard_Boolean);
4453 -- Build first two arguments for Check pragma
4456 Make_Pragma_Argument_Association (Loc,
4457 Expression => Make_Identifier (Loc, Name_Invariant)),
4458 Make_Pragma_Argument_Association (Loc, Expression => Exp));
4460 -- Add message if present in Invariant pragma
4462 if Present (Arg3) then
4463 Str := Strval (Get_Pragma_Arg (Arg3));
4465 -- If inherited case, and message starts "failed invariant",
4466 -- change it to be "failed inherited invariant".
4469 String_To_Name_Buffer (Str);
4471 if Name_Buffer (1 .. 16) = "failed invariant" then
4472 Insert_Str_In_Name_Buffer ("inherited ", 8);
4473 Str := String_From_Name_Buffer;
4478 Make_Pragma_Argument_Association (Loc,
4479 Expression => Make_String_Literal (Loc, Str)));
4482 -- Add Check pragma to list of statements
4486 Pragma_Identifier =>
4487 Make_Identifier (Loc, Name_Check),
4488 Pragma_Argument_Associations => Assoc));
4490 -- If Inherited case and option enabled, output info msg. Note
4491 -- that we know this is a case of Invariant'Class.
4493 if Inherit and Opt.List_Inherited_Aspects then
4494 Error_Msg_Sloc := Sloc (Ritem);
4496 ("?info: & inherits `Invariant''Class` aspect from #",
4502 Next_Rep_Item (Ritem);
4506 -- Start of processing for Build_Invariant_Procedure
4512 Set_Etype (Object_Entity, Typ);
4514 -- Add invariants for the current type
4516 Add_Invariants (Typ, Inherit => False);
4518 -- Add invariants for parent types
4521 Current_Typ : Entity_Id;
4522 Parent_Typ : Entity_Id;
4527 Parent_Typ := Etype (Current_Typ);
4529 if Is_Private_Type (Parent_Typ)
4530 and then Present (Full_View (Base_Type (Parent_Typ)))
4532 Parent_Typ := Full_View (Base_Type (Parent_Typ));
4535 exit when Parent_Typ = Current_Typ;
4537 Current_Typ := Parent_Typ;
4538 Add_Invariants (Current_Typ, Inherit => True);
4542 -- Build the procedure if we generated at least one Check pragma
4544 if Stmts /= No_List then
4546 -- Build procedure declaration
4549 Make_Defining_Identifier (Loc,
4550 Chars => New_External_Name (Chars (Typ), "Invariant"));
4551 Set_Has_Invariants (SId);
4552 Set_Invariant_Procedure (Typ, SId);
4555 Make_Procedure_Specification (Loc,
4556 Defining_Unit_Name => SId,
4557 Parameter_Specifications => New_List (
4558 Make_Parameter_Specification (Loc,
4559 Defining_Identifier => Object_Entity,
4560 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4562 PDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4564 -- Build procedure body
4567 Make_Defining_Identifier (Loc,
4568 Chars => New_External_Name (Chars (Typ), "Invariant"));
4571 Make_Procedure_Specification (Loc,
4572 Defining_Unit_Name => SId,
4573 Parameter_Specifications => New_List (
4574 Make_Parameter_Specification (Loc,
4575 Defining_Identifier =>
4576 Make_Defining_Identifier (Loc, Object_Name),
4577 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
4580 Make_Subprogram_Body (Loc,
4581 Specification => Spec,
4582 Declarations => Empty_List,
4583 Handled_Statement_Sequence =>
4584 Make_Handled_Sequence_Of_Statements (Loc,
4585 Statements => Stmts));
4587 -- Insert procedure declaration and spec at the appropriate points.
4588 -- Skip this if there are no private declarations (that's an error
4589 -- that will be diagnosed elsewhere, and there is no point in having
4590 -- an invariant procedure set if the full declaration is missing).
4592 if Present (Private_Decls) then
4594 -- The spec goes at the end of visible declarations, but they have
4595 -- already been analyzed, so we need to explicitly do the analyze.
4597 Append_To (Visible_Decls, PDecl);
4600 -- The body goes at the end of the private declarations, which we
4601 -- have not analyzed yet, so we do not need to perform an explicit
4602 -- analyze call. We skip this if there are no private declarations
4603 -- (this is an error that will be caught elsewhere);
4605 Append_To (Private_Decls, PBody);
4608 end Build_Invariant_Procedure;
4610 ------------------------------
4611 -- Build_Predicate_Function --
4612 ------------------------------
4614 -- The procedure that is constructed here has the form
4616 -- function typPredicate (Ixxx : typ) return Boolean is
4619 -- exp1 and then exp2 and then ...
4620 -- and then typ1Predicate (typ1 (Ixxx))
4621 -- and then typ2Predicate (typ2 (Ixxx))
4623 -- end typPredicate;
4625 -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that
4626 -- this is the point at which these expressions get analyzed, providing the
4627 -- required delay, and typ1, typ2, are entities from which predicates are
4628 -- inherited. Note that we do NOT generate Check pragmas, that's because we
4629 -- use this function even if checks are off, e.g. for membership tests.
4631 procedure Build_Predicate_Function (Typ : Entity_Id; N : Node_Id) is
4632 Loc : constant Source_Ptr := Sloc (Typ);
4639 -- This is the expression for the return statement in the function. It
4640 -- is build by connecting the component predicates with AND THEN.
4642 procedure Add_Call (T : Entity_Id);
4643 -- Includes a call to the predicate function for type T in Expr if T
4644 -- has predicates and Predicate_Function (T) is non-empty.
4646 procedure Add_Predicates;
4647 -- Appends expressions for any Predicate pragmas in the rep item chain
4648 -- Typ to Expr. Note that we look only at items for this exact entity.
4649 -- Inheritance of predicates for the parent type is done by calling the
4650 -- Predicate_Function of the parent type, using Add_Call above.
4652 Object_Name : constant Name_Id := New_Internal_Name ('I');
4653 -- Name for argument of Predicate procedure
4655 Object_Entity : constant Entity_Id :=
4656 Make_Defining_Identifier (Loc, Object_Name);
4657 -- The entity for the spec entity for the argument
4659 Dynamic_Predicate_Present : Boolean := False;
4660 -- Set True if a dynamic predicate is present, results in the entire
4661 -- predicate being considered dynamic even if it looks static
4663 Static_Predicate_Present : Node_Id := Empty;
4664 -- Set to N_Pragma node for a static predicate if one is encountered.
4670 procedure Add_Call (T : Entity_Id) is
4674 if Present (T) and then Present (Predicate_Function (T)) then
4675 Set_Has_Predicates (Typ);
4677 -- Build the call to the predicate function of T
4681 (T, Convert_To (T, Make_Identifier (Loc, Object_Name)));
4683 -- Add call to evolving expression, using AND THEN if needed
4690 Left_Opnd => Relocate_Node (Expr),
4694 -- Output info message on inheritance if required. Note we do not
4695 -- give this information for generic actual types, since it is
4696 -- unwelcome noise in that case in instantiations. We also
4697 -- generally suppress the message in instantiations, and also
4698 -- if it involves internal names.
4700 if Opt.List_Inherited_Aspects
4701 and then not Is_Generic_Actual_Type (Typ)
4702 and then Instantiation_Depth (Sloc (Typ)) = 0
4703 and then not Is_Internal_Name (Chars (T))
4704 and then not Is_Internal_Name (Chars (Typ))
4706 Error_Msg_Sloc := Sloc (Predicate_Function (T));
4707 Error_Msg_Node_2 := T;
4708 Error_Msg_N ("?info: & inherits predicate from & #", Typ);
4713 --------------------
4714 -- Add_Predicates --
4715 --------------------
4717 procedure Add_Predicates is
4722 procedure Replace_Type_Reference (N : Node_Id);
4723 -- Replace a single occurrence N of the subtype name with a reference
4724 -- to the formal of the predicate function. N can be an identifier
4725 -- referencing the subtype, or a selected component, representing an
4726 -- appropriately qualified occurrence of the subtype name.
4728 procedure Replace_Type_References is
4729 new Replace_Type_References_Generic (Replace_Type_Reference);
4730 -- Traverse an expression changing every occurrence of an identifier
4731 -- whose name matches the name of the subtype with a reference to
4732 -- the formal parameter of the predicate function.
4734 ----------------------------
4735 -- Replace_Type_Reference --
4736 ----------------------------
4738 procedure Replace_Type_Reference (N : Node_Id) is
4740 Rewrite (N, Make_Identifier (Loc, Object_Name));
4741 Set_Entity (N, Object_Entity);
4743 end Replace_Type_Reference;
4745 -- Start of processing for Add_Predicates
4748 Ritem := First_Rep_Item (Typ);
4749 while Present (Ritem) loop
4750 if Nkind (Ritem) = N_Pragma
4751 and then Pragma_Name (Ritem) = Name_Predicate
4753 if From_Dynamic_Predicate (Ritem) then
4754 Dynamic_Predicate_Present := True;
4755 elsif From_Static_Predicate (Ritem) then
4756 Static_Predicate_Present := Ritem;
4759 -- Acquire arguments
4761 Arg1 := First (Pragma_Argument_Associations (Ritem));
4762 Arg2 := Next (Arg1);
4764 Arg1 := Get_Pragma_Arg (Arg1);
4765 Arg2 := Get_Pragma_Arg (Arg2);
4767 -- See if this predicate pragma is for the current type or for
4768 -- its full view. A predicate on a private completion is placed
4769 -- on the partial view beause this is the visible entity that
4772 if Entity (Arg1) = Typ
4773 or else Full_View (Entity (Arg1)) = Typ
4776 -- We have a match, this entry is for our subtype
4778 -- We need to replace any occurrences of the name of the
4779 -- type with references to the object.
4781 Replace_Type_References (Arg2, Chars (Typ));
4783 -- If this predicate comes from an aspect, find the aspect
4784 -- specification, and replace the saved expression because
4785 -- we need the subtype references replaced for the calls to
4786 -- Preanalyze_Spec_Expressin in Check_Aspect_At_Freeze_Point
4787 -- and Check_Aspect_At_End_Of_Declarations.
4789 if From_Aspect_Specification (Ritem) then
4794 -- Loop to find corresponding aspect, note that this
4795 -- must be present given the pragma is marked delayed.
4797 Aitem := Next_Rep_Item (Ritem);
4799 if Nkind (Aitem) = N_Aspect_Specification
4800 and then Aspect_Rep_Item (Aitem) = Ritem
4803 (Identifier (Aitem), New_Copy_Tree (Arg2));
4807 Aitem := Next_Rep_Item (Aitem);
4812 -- Now we can add the expression
4815 Expr := Relocate_Node (Arg2);
4817 -- There already was a predicate, so add to it
4822 Left_Opnd => Relocate_Node (Expr),
4823 Right_Opnd => Relocate_Node (Arg2));
4828 Next_Rep_Item (Ritem);
4832 -- Start of processing for Build_Predicate_Function
4835 -- Initialize for construction of statement list
4839 -- Return if already built or if type does not have predicates
4841 if not Has_Predicates (Typ)
4842 or else Present (Predicate_Function (Typ))
4847 -- Add Predicates for the current type
4851 -- Add predicates for ancestor if present
4854 Atyp : constant Entity_Id := Nearest_Ancestor (Typ);
4856 if Present (Atyp) then
4861 -- If we have predicates, build the function
4863 if Present (Expr) then
4865 -- Build function declaration
4867 pragma Assert (Has_Predicates (Typ));
4869 Make_Defining_Identifier (Loc,
4870 Chars => New_External_Name (Chars (Typ), "Predicate"));
4871 Set_Has_Predicates (SId);
4872 Set_Predicate_Function (Typ, SId);
4875 Make_Function_Specification (Loc,
4876 Defining_Unit_Name => SId,
4877 Parameter_Specifications => New_List (
4878 Make_Parameter_Specification (Loc,
4879 Defining_Identifier => Object_Entity,
4880 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
4881 Result_Definition =>
4882 New_Occurrence_Of (Standard_Boolean, Loc));
4884 FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec);
4886 -- Build function body
4889 Make_Defining_Identifier (Loc,
4890 Chars => New_External_Name (Chars (Typ), "Predicate"));
4893 Make_Function_Specification (Loc,
4894 Defining_Unit_Name => SId,
4895 Parameter_Specifications => New_List (
4896 Make_Parameter_Specification (Loc,
4897 Defining_Identifier =>
4898 Make_Defining_Identifier (Loc, Object_Name),
4900 New_Occurrence_Of (Typ, Loc))),
4901 Result_Definition =>
4902 New_Occurrence_Of (Standard_Boolean, Loc));
4905 Make_Subprogram_Body (Loc,
4906 Specification => Spec,
4907 Declarations => Empty_List,
4908 Handled_Statement_Sequence =>
4909 Make_Handled_Sequence_Of_Statements (Loc,
4910 Statements => New_List (
4911 Make_Simple_Return_Statement (Loc,
4912 Expression => Expr))));
4914 -- Insert declaration before freeze node and body after
4916 Insert_Before_And_Analyze (N, FDecl);
4917 Insert_After_And_Analyze (N, FBody);
4919 -- Deal with static predicate case
4921 if Ekind_In (Typ, E_Enumeration_Subtype,
4922 E_Modular_Integer_Subtype,
4923 E_Signed_Integer_Subtype)
4924 and then Is_Static_Subtype (Typ)
4925 and then not Dynamic_Predicate_Present
4927 Build_Static_Predicate (Typ, Expr, Object_Name);
4929 if Present (Static_Predicate_Present)
4930 and No (Static_Predicate (Typ))
4933 ("expression does not have required form for "
4934 & "static predicate",
4935 Next (First (Pragma_Argument_Associations
4936 (Static_Predicate_Present))));
4940 end Build_Predicate_Function;
4942 ----------------------------
4943 -- Build_Static_Predicate --
4944 ----------------------------
4946 procedure Build_Static_Predicate
4951 Loc : constant Source_Ptr := Sloc (Expr);
4953 Non_Static : exception;
4954 -- Raised if something non-static is found
4956 Btyp : constant Entity_Id := Base_Type (Typ);
4958 BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp));
4959 BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp));
4960 -- Low bound and high bound value of base type of Typ
4962 TLo : constant Uint := Expr_Value (Type_Low_Bound (Typ));
4963 THi : constant Uint := Expr_Value (Type_High_Bound (Typ));
4964 -- Low bound and high bound values of static subtype Typ
4969 -- One entry in a Rlist value, a single REnt (range entry) value
4970 -- denotes one range from Lo to Hi. To represent a single value
4971 -- range Lo = Hi = value.
4973 type RList is array (Nat range <>) of REnt;
4974 -- A list of ranges. The ranges are sorted in increasing order,
4975 -- and are disjoint (there is a gap of at least one value between
4976 -- each range in the table). A value is in the set of ranges in
4977 -- Rlist if it lies within one of these ranges
4979 False_Range : constant RList :=
4980 RList'(1 .. 0 => REnt'(No_Uint, No_Uint));
4981 -- An empty set of ranges represents a range list that can never be
4982 -- satisfied, since there are no ranges in which the value could lie,
4983 -- so it does not lie in any of them. False_Range is a canonical value
4984 -- for this empty set, but general processing should test for an Rlist
4985 -- with length zero (see Is_False predicate), since other null ranges
4986 -- may appear which must be treated as False.
4988 True_Range : constant RList := RList'(1 => REnt'(BLo, BHi));
4989 -- Range representing True, value must be in the base range
4991 function "and" (Left, Right : RList) return RList;
4992 -- And's together two range lists, returning a range list. This is
4993 -- a set intersection operation.
4995 function "or" (Left, Right : RList) return RList;
4996 -- Or's together two range lists, returning a range list. This is a
4997 -- set union operation.
4999 function "not" (Right : RList) return RList;
5000 -- Returns complement of a given range list, i.e. a range list
5001 -- representing all the values in TLo .. THi that are not in the
5002 -- input operand Right.
5004 function Build_Val (V : Uint) return Node_Id;
5005 -- Return an analyzed N_Identifier node referencing this value, suitable
5006 -- for use as an entry in the Static_Predicate list. This node is typed
5007 -- with the base type.
5009 function Build_Range (Lo, Hi : Uint) return Node_Id;
5010 -- Return an analyzed N_Range node referencing this range, suitable
5011 -- for use as an entry in the Static_Predicate list. This node is typed
5012 -- with the base type.
5014 function Get_RList (Exp : Node_Id) return RList;
5015 -- This is a recursive routine that converts the given expression into
5016 -- a list of ranges, suitable for use in building the static predicate.
5018 function Is_False (R : RList) return Boolean;
5019 pragma Inline (Is_False);
5020 -- Returns True if the given range list is empty, and thus represents
5021 -- a False list of ranges that can never be satisfied.
5023 function Is_True (R : RList) return Boolean;
5024 -- Returns True if R trivially represents the True predicate by having
5025 -- a single range from BLo to BHi.
5027 function Is_Type_Ref (N : Node_Id) return Boolean;
5028 pragma Inline (Is_Type_Ref);
5029 -- Returns if True if N is a reference to the type for the predicate in
5030 -- the expression (i.e. if it is an identifier whose Chars field matches
5031 -- the Nam given in the call).
5033 function Lo_Val (N : Node_Id) return Uint;
5034 -- Given static expression or static range from a Static_Predicate list,
5035 -- gets expression value or low bound of range.
5037 function Hi_Val (N : Node_Id) return Uint;
5038 -- Given static expression or static range from a Static_Predicate list,
5039 -- gets expression value of high bound of range.
5041 function Membership_Entry (N : Node_Id) return RList;
5042 -- Given a single membership entry (range, value, or subtype), returns
5043 -- the corresponding range list. Raises Static_Error if not static.
5045 function Membership_Entries (N : Node_Id) return RList;
5046 -- Given an element on an alternatives list of a membership operation,
5047 -- returns the range list corresponding to this entry and all following
5048 -- entries (i.e. returns the "or" of this list of values).
5050 function Stat_Pred (Typ : Entity_Id) return RList;
5051 -- Given a type, if it has a static predicate, then return the predicate
5052 -- as a range list, otherwise raise Non_Static.
5058 function "and" (Left, Right : RList) return RList is
5060 -- First range of result
5062 SLeft : Nat := Left'First;
5063 -- Start of rest of left entries
5065 SRight : Nat := Right'First;
5066 -- Start of rest of right entries
5069 -- If either range is True, return the other
5071 if Is_True (Left) then
5073 elsif Is_True (Right) then
5077 -- If either range is False, return False
5079 if Is_False (Left) or else Is_False (Right) then
5083 -- Loop to remove entries at start that are disjoint, and thus
5084 -- just get discarded from the result entirely.
5087 -- If no operands left in either operand, result is false
5089 if SLeft > Left'Last or else SRight > Right'Last then
5092 -- Discard first left operand entry if disjoint with right
5094 elsif Left (SLeft).Hi < Right (SRight).Lo then
5097 -- Discard first right operand entry if disjoint with left
5099 elsif Right (SRight).Hi < Left (SLeft).Lo then
5100 SRight := SRight + 1;
5102 -- Otherwise we have an overlapping entry
5109 -- Now we have two non-null operands, and first entries overlap.
5110 -- The first entry in the result will be the overlapping part of
5111 -- these two entries.
5113 FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo),
5114 Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi));
5116 -- Now we can remove the entry that ended at a lower value, since
5117 -- its contribution is entirely contained in Fent.
5119 if Left (SLeft).Hi <= Right (SRight).Hi then
5122 SRight := SRight + 1;
5125 -- Compute result by concatenating this first entry with the "and"
5126 -- of the remaining parts of the left and right operands. Note that
5127 -- if either of these is empty, "and" will yield empty, so that we
5128 -- will end up with just Fent, which is what we want in that case.
5131 FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last));
5138 function "not" (Right : RList) return RList is
5140 -- Return True if False range
5142 if Is_False (Right) then
5146 -- Return False if True range
5148 if Is_True (Right) then
5152 -- Here if not trivial case
5155 Result : RList (1 .. Right'Length + 1);
5156 -- May need one more entry for gap at beginning and end
5159 -- Number of entries stored in Result
5164 if Right (Right'First).Lo > TLo then
5166 Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1);
5169 -- Gaps between ranges
5171 for J in Right'First .. Right'Last - 1 loop
5174 REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1);
5179 if Right (Right'Last).Hi < THi then
5181 Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi);
5184 return Result (1 .. Count);
5192 function "or" (Left, Right : RList) return RList is
5194 -- First range of result
5196 SLeft : Nat := Left'First;
5197 -- Start of rest of left entries
5199 SRight : Nat := Right'First;
5200 -- Start of rest of right entries
5203 -- If either range is True, return True
5205 if Is_True (Left) or else Is_True (Right) then
5209 -- If either range is False (empty), return the other
5211 if Is_False (Left) then
5213 elsif Is_False (Right) then
5217 -- Initialize result first entry from left or right operand
5218 -- depending on which starts with the lower range.
5220 if Left (SLeft).Lo < Right (SRight).Lo then
5221 FEnt := Left (SLeft);
5224 FEnt := Right (SRight);
5225 SRight := SRight + 1;
5228 -- This loop eats ranges from left and right operands that
5229 -- are contiguous with the first range we are gathering.
5232 -- Eat first entry in left operand if contiguous or
5233 -- overlapped by gathered first operand of result.
5235 if SLeft <= Left'Last
5236 and then Left (SLeft).Lo <= FEnt.Hi + 1
5238 FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi);
5241 -- Eat first entry in right operand if contiguous or
5242 -- overlapped by gathered right operand of result.
5244 elsif SRight <= Right'Last
5245 and then Right (SRight).Lo <= FEnt.Hi + 1
5247 FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi);
5248 SRight := SRight + 1;
5250 -- All done if no more entries to eat!
5257 -- Obtain result as the first entry we just computed, concatenated
5258 -- to the "or" of the remaining results (if one operand is empty,
5259 -- this will just concatenate with the other
5262 FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last));
5269 function Build_Range (Lo, Hi : Uint) return Node_Id is
5273 return Build_Val (Hi);
5277 Low_Bound => Build_Val (Lo),
5278 High_Bound => Build_Val (Hi));
5279 Set_Etype (Result, Btyp);
5280 Set_Analyzed (Result);
5289 function Build_Val (V : Uint) return Node_Id is
5293 if Is_Enumeration_Type (Typ) then
5294 Result := Get_Enum_Lit_From_Pos (Typ, V, Loc);
5296 Result := Make_Integer_Literal (Loc, V);
5299 Set_Etype (Result, Btyp);
5300 Set_Is_Static_Expression (Result);
5301 Set_Analyzed (Result);
5309 function Get_RList (Exp : Node_Id) return RList is
5314 -- Static expression can only be true or false
5316 if Is_OK_Static_Expression (Exp) then
5320 if Expr_Value (Exp) = 0 then
5327 -- Otherwise test node type
5335 when N_Op_And | N_And_Then =>
5336 return Get_RList (Left_Opnd (Exp))
5338 Get_RList (Right_Opnd (Exp));
5342 when N_Op_Or | N_Or_Else =>
5343 return Get_RList (Left_Opnd (Exp))
5345 Get_RList (Right_Opnd (Exp));
5350 return not Get_RList (Right_Opnd (Exp));
5352 -- Comparisons of type with static value
5354 when N_Op_Compare =>
5355 -- Type is left operand
5357 if Is_Type_Ref (Left_Opnd (Exp))
5358 and then Is_OK_Static_Expression (Right_Opnd (Exp))
5360 Val := Expr_Value (Right_Opnd (Exp));
5362 -- Typ is right operand
5364 elsif Is_Type_Ref (Right_Opnd (Exp))
5365 and then Is_OK_Static_Expression (Left_Opnd (Exp))
5367 Val := Expr_Value (Left_Opnd (Exp));
5369 -- Invert sense of comparison
5372 when N_Op_Gt => Op := N_Op_Lt;
5373 when N_Op_Lt => Op := N_Op_Gt;
5374 when N_Op_Ge => Op := N_Op_Le;
5375 when N_Op_Le => Op := N_Op_Ge;
5376 when others => null;
5379 -- Other cases are non-static
5385 -- Construct range according to comparison operation
5389 return RList'(1 => REnt'(Val, Val));
5392 return RList'(1 => REnt'(Val, BHi));
5395 return RList'(1 => REnt'(Val + 1, BHi));
5398 return RList'(1 => REnt'(BLo, Val));
5401 return RList'(1 => REnt'(BLo, Val - 1));
5404 return RList'(REnt'(BLo, Val - 1),
5405 REnt'(Val + 1, BHi));
5408 raise Program_Error;
5414 if not Is_Type_Ref (Left_Opnd (Exp)) then
5418 if Present (Right_Opnd (Exp)) then
5419 return Membership_Entry (Right_Opnd (Exp));
5421 return Membership_Entries (First (Alternatives (Exp)));
5424 -- Negative membership (NOT IN)
5427 if not Is_Type_Ref (Left_Opnd (Exp)) then
5431 if Present (Right_Opnd (Exp)) then
5432 return not Membership_Entry (Right_Opnd (Exp));
5434 return not Membership_Entries (First (Alternatives (Exp)));
5437 -- Function call, may be call to static predicate
5439 when N_Function_Call =>
5440 if Is_Entity_Name (Name (Exp)) then
5442 Ent : constant Entity_Id := Entity (Name (Exp));
5444 if Has_Predicates (Ent) then
5445 return Stat_Pred (Etype (First_Formal (Ent)));
5450 -- Other function call cases are non-static
5454 -- Qualified expression, dig out the expression
5456 when N_Qualified_Expression =>
5457 return Get_RList (Expression (Exp));
5462 return (Get_RList (Left_Opnd (Exp))
5463 and not Get_RList (Right_Opnd (Exp)))
5464 or (Get_RList (Right_Opnd (Exp))
5465 and not Get_RList (Left_Opnd (Exp)));
5467 -- Any other node type is non-static
5478 function Hi_Val (N : Node_Id) return Uint is
5480 if Is_Static_Expression (N) then
5481 return Expr_Value (N);
5483 pragma Assert (Nkind (N) = N_Range);
5484 return Expr_Value (High_Bound (N));
5492 function Is_False (R : RList) return Boolean is
5494 return R'Length = 0;
5501 function Is_True (R : RList) return Boolean is
5504 and then R (R'First).Lo = BLo
5505 and then R (R'First).Hi = BHi;
5512 function Is_Type_Ref (N : Node_Id) return Boolean is
5514 return Nkind (N) = N_Identifier and then Chars (N) = Nam;
5521 function Lo_Val (N : Node_Id) return Uint is
5523 if Is_Static_Expression (N) then
5524 return Expr_Value (N);
5526 pragma Assert (Nkind (N) = N_Range);
5527 return Expr_Value (Low_Bound (N));
5531 ------------------------
5532 -- Membership_Entries --
5533 ------------------------
5535 function Membership_Entries (N : Node_Id) return RList is
5537 if No (Next (N)) then
5538 return Membership_Entry (N);
5540 return Membership_Entry (N) or Membership_Entries (Next (N));
5542 end Membership_Entries;
5544 ----------------------
5545 -- Membership_Entry --
5546 ----------------------
5548 function Membership_Entry (N : Node_Id) return RList is
5556 if Nkind (N) = N_Range then
5557 if not Is_Static_Expression (Low_Bound (N))
5559 not Is_Static_Expression (High_Bound (N))
5563 SLo := Expr_Value (Low_Bound (N));
5564 SHi := Expr_Value (High_Bound (N));
5565 return RList'(1 => REnt'(SLo, SHi));
5568 -- Static expression case
5570 elsif Is_Static_Expression (N) then
5571 Val := Expr_Value (N);
5572 return RList'(1 => REnt'(Val, Val));
5574 -- Identifier (other than static expression) case
5576 else pragma Assert (Nkind (N) = N_Identifier);
5580 if Is_Type (Entity (N)) then
5582 -- If type has predicates, process them
5584 if Has_Predicates (Entity (N)) then
5585 return Stat_Pred (Entity (N));
5587 -- For static subtype without predicates, get range
5589 elsif Is_Static_Subtype (Entity (N)) then
5590 SLo := Expr_Value (Type_Low_Bound (Entity (N)));
5591 SHi := Expr_Value (Type_High_Bound (Entity (N)));
5592 return RList'(1 => REnt'(SLo, SHi));
5594 -- Any other type makes us non-static
5600 -- Any other kind of identifier in predicate (e.g. a non-static
5601 -- expression value) means this is not a static predicate.
5607 end Membership_Entry;
5613 function Stat_Pred (Typ : Entity_Id) return RList is
5615 -- Not static if type does not have static predicates
5617 if not Has_Predicates (Typ)
5618 or else No (Static_Predicate (Typ))
5623 -- Otherwise we convert the predicate list to a range list
5626 Result : RList (1 .. List_Length (Static_Predicate (Typ)));
5630 P := First (Static_Predicate (Typ));
5631 for J in Result'Range loop
5632 Result (J) := REnt'(Lo_Val (P), Hi_Val (P));
5640 -- Start of processing for Build_Static_Predicate
5643 -- Now analyze the expression to see if it is a static predicate
5646 Ranges : constant RList := Get_RList (Expr);
5647 -- Range list from expression if it is static
5652 -- Convert range list into a form for the static predicate. In the
5653 -- Ranges array, we just have raw ranges, these must be converted
5654 -- to properly typed and analyzed static expressions or range nodes.
5656 -- Note: here we limit ranges to the ranges of the subtype, so that
5657 -- a predicate is always false for values outside the subtype. That
5658 -- seems fine, such values are invalid anyway, and considering them
5659 -- to fail the predicate seems allowed and friendly, and furthermore
5660 -- simplifies processing for case statements and loops.
5664 for J in Ranges'Range loop
5666 Lo : Uint := Ranges (J).Lo;
5667 Hi : Uint := Ranges (J).Hi;
5670 -- Ignore completely out of range entry
5672 if Hi < TLo or else Lo > THi then
5675 -- Otherwise process entry
5678 -- Adjust out of range value to subtype range
5688 -- Convert range into required form
5691 Append_To (Plist, Build_Val (Lo));
5693 Append_To (Plist, Build_Range (Lo, Hi));
5699 -- Processing was successful and all entries were static, so now we
5700 -- can store the result as the predicate list.
5702 Set_Static_Predicate (Typ, Plist);
5704 -- The processing for static predicates put the expression into
5705 -- canonical form as a series of ranges. It also eliminated
5706 -- duplicates and collapsed and combined ranges. We might as well
5707 -- replace the alternatives list of the right operand of the
5708 -- membership test with the static predicate list, which will
5709 -- usually be more efficient.
5712 New_Alts : constant List_Id := New_List;
5717 Old_Node := First (Plist);
5718 while Present (Old_Node) loop
5719 New_Node := New_Copy (Old_Node);
5721 if Nkind (New_Node) = N_Range then
5722 Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node)));
5723 Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node)));
5726 Append_To (New_Alts, New_Node);
5730 -- If empty list, replace by False
5732 if Is_Empty_List (New_Alts) then
5733 Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc));
5735 -- Else replace by set membership test
5740 Left_Opnd => Make_Identifier (Loc, Nam),
5741 Right_Opnd => Empty,
5742 Alternatives => New_Alts));
5744 -- Resolve new expression in function context
5746 Install_Formals (Predicate_Function (Typ));
5747 Push_Scope (Predicate_Function (Typ));
5748 Analyze_And_Resolve (Expr, Standard_Boolean);
5754 -- If non-static, return doing nothing
5759 end Build_Static_Predicate;
5761 -----------------------------------------
5762 -- Check_Aspect_At_End_Of_Declarations --
5763 -----------------------------------------
5765 procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is
5766 Ent : constant Entity_Id := Entity (ASN);
5767 Ident : constant Node_Id := Identifier (ASN);
5769 Freeze_Expr : constant Node_Id := Expression (ASN);
5770 -- Expression from call to Check_Aspect_At_Freeze_Point
5772 End_Decl_Expr : constant Node_Id := Entity (Ident);
5773 -- Expression to be analyzed at end of declarations
5775 T : constant Entity_Id := Etype (Freeze_Expr);
5776 -- Type required for preanalyze call
5778 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5781 -- Set False if error
5783 -- On entry to this procedure, Entity (Ident) contains a copy of the
5784 -- original expression from the aspect, saved for this purpose, and
5785 -- but Expression (Ident) is a preanalyzed copy of the expression,
5786 -- preanalyzed just after the freeze point.
5789 -- Case of stream attributes, just have to compare entities
5791 if A_Id = Aspect_Input or else
5792 A_Id = Aspect_Output or else
5793 A_Id = Aspect_Read or else
5796 Analyze (End_Decl_Expr);
5797 Err := Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5799 elsif A_Id = Aspect_Variable_Indexing or else
5800 A_Id = Aspect_Constant_Indexing or else
5801 A_Id = Aspect_Default_Iterator or else
5802 A_Id = Aspect_Iterator_Element
5804 -- Make type unfrozen before analysis, to prevent spurious errors
5805 -- about late attributes.
5807 Set_Is_Frozen (Ent, False);
5808 Analyze (End_Decl_Expr);
5809 Analyze (Aspect_Rep_Item (ASN));
5810 Set_Is_Frozen (Ent, True);
5812 -- If the end of declarations comes before any other freeze
5813 -- point, the Freeze_Expr is not analyzed: no check needed.
5816 Analyzed (Freeze_Expr)
5817 and then not In_Instance
5818 and then Entity (End_Decl_Expr) /= Entity (Freeze_Expr);
5823 Preanalyze_Spec_Expression (End_Decl_Expr, T);
5824 Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr);
5827 -- Output error message if error
5831 ("visibility of aspect for& changes after freeze point",
5834 ("?info: & is frozen here, aspects evaluated at this point",
5835 Freeze_Node (Ent), Ent);
5837 end Check_Aspect_At_End_Of_Declarations;
5839 ----------------------------------
5840 -- Check_Aspect_At_Freeze_Point --
5841 ----------------------------------
5843 procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is
5844 Ident : constant Node_Id := Identifier (ASN);
5845 -- Identifier (use Entity field to save expression)
5848 -- Type required for preanalyze call
5850 A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident));
5853 -- On entry to this procedure, Entity (Ident) contains a copy of the
5854 -- original expression from the aspect, saved for this purpose.
5856 -- On exit from this procedure Entity (Ident) is unchanged, still
5857 -- containing that copy, but Expression (Ident) is a preanalyzed copy
5858 -- of the expression, preanalyzed just after the freeze point.
5860 -- Make a copy of the expression to be preanalyed
5862 Set_Expression (ASN, New_Copy_Tree (Entity (Ident)));
5864 -- Find type for preanalyze call
5868 -- No_Aspect should be impossible
5871 raise Program_Error;
5873 -- Library unit aspects should be impossible (never delayed)
5875 when Library_Unit_Aspects =>
5876 raise Program_Error;
5878 -- Aspects taking an optional boolean argument. Should be impossible
5879 -- since these are never delayed.
5881 when Boolean_Aspects =>
5882 raise Program_Error;
5884 -- Test_Case aspect applies to entries and subprograms, hence should
5885 -- never be delayed.
5887 when Aspect_Test_Case =>
5888 raise Program_Error;
5890 when Aspect_Attach_Handler =>
5891 T := RTE (RE_Interrupt_ID);
5893 -- Default_Value is resolved with the type entity in question
5895 when Aspect_Default_Value =>
5898 -- Default_Component_Value is resolved with the component type
5900 when Aspect_Default_Component_Value =>
5901 T := Component_Type (Entity (ASN));
5903 -- Aspects corresponding to attribute definition clauses
5905 when Aspect_Address =>
5906 T := RTE (RE_Address);
5908 when Aspect_Bit_Order =>
5909 T := RTE (RE_Bit_Order);
5912 T := RTE (RE_CPU_Range);
5914 when Aspect_Dispatching_Domain =>
5915 T := RTE (RE_Dispatching_Domain);
5917 when Aspect_External_Tag =>
5918 T := Standard_String;
5920 when Aspect_Priority | Aspect_Interrupt_Priority =>
5921 T := Standard_Integer;
5923 when Aspect_Small =>
5924 T := Universal_Real;
5926 when Aspect_Storage_Pool =>
5927 T := Class_Wide_Type (RTE (RE_Root_Storage_Pool));
5929 when Aspect_Alignment |
5930 Aspect_Component_Size |
5931 Aspect_Machine_Radix |
5932 Aspect_Object_Size |
5934 Aspect_Storage_Size |
5935 Aspect_Stream_Size |
5936 Aspect_Value_Size =>
5939 -- Stream attribute. Special case, the expression is just an entity
5940 -- that does not need any resolution, so just analyze.
5946 Analyze (Expression (ASN));
5949 -- Same for Iterator aspects, where the expression is a function
5950 -- name. Legality rules are checked separately.
5952 when Aspect_Constant_Indexing |
5953 Aspect_Default_Iterator |
5954 Aspect_Iterator_Element |
5955 Aspect_Implicit_Dereference |
5956 Aspect_Variable_Indexing =>
5957 Analyze (Expression (ASN));
5960 -- Suppress/Unsuppress/Warnings should never be delayed
5962 when Aspect_Suppress |
5965 raise Program_Error;
5967 -- Pre/Post/Invariant/Predicate take boolean expressions
5969 when Aspect_Dynamic_Predicate |
5972 Aspect_Precondition |
5974 Aspect_Postcondition |
5976 Aspect_Static_Predicate |
5977 Aspect_Type_Invariant =>
5978 T := Standard_Boolean;
5981 -- Do the preanalyze call
5983 Preanalyze_Spec_Expression (Expression (ASN), T);
5984 end Check_Aspect_At_Freeze_Point;
5986 -----------------------------------
5987 -- Check_Constant_Address_Clause --
5988 -----------------------------------
5990 procedure Check_Constant_Address_Clause
5994 procedure Check_At_Constant_Address (Nod : Node_Id);
5995 -- Checks that the given node N represents a name whose 'Address is
5996 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
5997 -- address value is the same at the point of declaration of U_Ent and at
5998 -- the time of elaboration of the address clause.
6000 procedure Check_Expr_Constants (Nod : Node_Id);
6001 -- Checks that Nod meets the requirements for a constant address clause
6002 -- in the sense of the enclosing procedure.
6004 procedure Check_List_Constants (Lst : List_Id);
6005 -- Check that all elements of list Lst meet the requirements for a
6006 -- constant address clause in the sense of the enclosing procedure.
6008 -------------------------------
6009 -- Check_At_Constant_Address --
6010 -------------------------------
6012 procedure Check_At_Constant_Address (Nod : Node_Id) is
6014 if Is_Entity_Name (Nod) then
6015 if Present (Address_Clause (Entity ((Nod)))) then
6017 ("invalid address clause for initialized object &!",
6020 ("address for& cannot" &
6021 " depend on another address clause! (RM 13.1(22))!",
6024 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
6025 and then Sloc (U_Ent) < Sloc (Entity (Nod))
6028 ("invalid address clause for initialized object &!",
6030 Error_Msg_Node_2 := U_Ent;
6032 ("\& must be defined before & (RM 13.1(22))!",
6036 elsif Nkind (Nod) = N_Selected_Component then
6038 T : constant Entity_Id := Etype (Prefix (Nod));
6041 if (Is_Record_Type (T)
6042 and then Has_Discriminants (T))
6045 and then Is_Record_Type (Designated_Type (T))
6046 and then Has_Discriminants (Designated_Type (T)))
6049 ("invalid address clause for initialized object &!",
6052 ("\address cannot depend on component" &
6053 " of discriminated record (RM 13.1(22))!",
6056 Check_At_Constant_Address (Prefix (Nod));
6060 elsif Nkind (Nod) = N_Indexed_Component then
6061 Check_At_Constant_Address (Prefix (Nod));
6062 Check_List_Constants (Expressions (Nod));
6065 Check_Expr_Constants (Nod);
6067 end Check_At_Constant_Address;
6069 --------------------------
6070 -- Check_Expr_Constants --
6071 --------------------------
6073 procedure Check_Expr_Constants (Nod : Node_Id) is
6074 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
6075 Ent : Entity_Id := Empty;
6078 if Nkind (Nod) in N_Has_Etype
6079 and then Etype (Nod) = Any_Type
6085 when N_Empty | N_Error =>
6088 when N_Identifier | N_Expanded_Name =>
6089 Ent := Entity (Nod);
6091 -- We need to look at the original node if it is different
6092 -- from the node, since we may have rewritten things and
6093 -- substituted an identifier representing the rewrite.
6095 if Original_Node (Nod) /= Nod then
6096 Check_Expr_Constants (Original_Node (Nod));
6098 -- If the node is an object declaration without initial
6099 -- value, some code has been expanded, and the expression
6100 -- is not constant, even if the constituents might be
6101 -- acceptable, as in A'Address + offset.
6103 if Ekind (Ent) = E_Variable
6105 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
6107 No (Expression (Declaration_Node (Ent)))
6110 ("invalid address clause for initialized object &!",
6113 -- If entity is constant, it may be the result of expanding
6114 -- a check. We must verify that its declaration appears
6115 -- before the object in question, else we also reject the
6118 elsif Ekind (Ent) = E_Constant
6119 and then In_Same_Source_Unit (Ent, U_Ent)
6120 and then Sloc (Ent) > Loc_U_Ent
6123 ("invalid address clause for initialized object &!",
6130 -- Otherwise look at the identifier and see if it is OK
6132 if Ekind_In (Ent, E_Named_Integer, E_Named_Real)
6133 or else Is_Type (Ent)
6138 Ekind (Ent) = E_Constant
6140 Ekind (Ent) = E_In_Parameter
6142 -- This is the case where we must have Ent defined before
6143 -- U_Ent. Clearly if they are in different units this
6144 -- requirement is met since the unit containing Ent is
6145 -- already processed.
6147 if not In_Same_Source_Unit (Ent, U_Ent) then
6150 -- Otherwise location of Ent must be before the location
6151 -- of U_Ent, that's what prior defined means.
6153 elsif Sloc (Ent) < Loc_U_Ent then
6158 ("invalid address clause for initialized object &!",
6160 Error_Msg_Node_2 := U_Ent;
6162 ("\& must be defined before & (RM 13.1(22))!",
6166 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
6167 Check_Expr_Constants (Original_Node (Nod));
6171 ("invalid address clause for initialized object &!",
6174 if Comes_From_Source (Ent) then
6176 ("\reference to variable& not allowed"
6177 & " (RM 13.1(22))!", Nod, Ent);
6180 ("non-static expression not allowed"
6181 & " (RM 13.1(22))!", Nod);
6185 when N_Integer_Literal =>
6187 -- If this is a rewritten unchecked conversion, in a system
6188 -- where Address is an integer type, always use the base type
6189 -- for a literal value. This is user-friendly and prevents
6190 -- order-of-elaboration issues with instances of unchecked
6193 if Nkind (Original_Node (Nod)) = N_Function_Call then
6194 Set_Etype (Nod, Base_Type (Etype (Nod)));
6197 when N_Real_Literal |
6199 N_Character_Literal =>
6203 Check_Expr_Constants (Low_Bound (Nod));
6204 Check_Expr_Constants (High_Bound (Nod));
6206 when N_Explicit_Dereference =>
6207 Check_Expr_Constants (Prefix (Nod));
6209 when N_Indexed_Component =>
6210 Check_Expr_Constants (Prefix (Nod));
6211 Check_List_Constants (Expressions (Nod));
6214 Check_Expr_Constants (Prefix (Nod));
6215 Check_Expr_Constants (Discrete_Range (Nod));
6217 when N_Selected_Component =>
6218 Check_Expr_Constants (Prefix (Nod));
6220 when N_Attribute_Reference =>
6221 if Attribute_Name (Nod) = Name_Address
6223 Attribute_Name (Nod) = Name_Access
6225 Attribute_Name (Nod) = Name_Unchecked_Access
6227 Attribute_Name (Nod) = Name_Unrestricted_Access
6229 Check_At_Constant_Address (Prefix (Nod));
6232 Check_Expr_Constants (Prefix (Nod));
6233 Check_List_Constants (Expressions (Nod));
6237 Check_List_Constants (Component_Associations (Nod));
6238 Check_List_Constants (Expressions (Nod));
6240 when N_Component_Association =>
6241 Check_Expr_Constants (Expression (Nod));
6243 when N_Extension_Aggregate =>
6244 Check_Expr_Constants (Ancestor_Part (Nod));
6245 Check_List_Constants (Component_Associations (Nod));
6246 Check_List_Constants (Expressions (Nod));
6251 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
6252 Check_Expr_Constants (Left_Opnd (Nod));
6253 Check_Expr_Constants (Right_Opnd (Nod));
6256 Check_Expr_Constants (Right_Opnd (Nod));
6258 when N_Type_Conversion |
6259 N_Qualified_Expression |
6261 Check_Expr_Constants (Expression (Nod));
6263 when N_Unchecked_Type_Conversion =>
6264 Check_Expr_Constants (Expression (Nod));
6266 -- If this is a rewritten unchecked conversion, subtypes in
6267 -- this node are those created within the instance. To avoid
6268 -- order of elaboration issues, replace them with their base
6269 -- types. Note that address clauses can cause order of
6270 -- elaboration problems because they are elaborated by the
6271 -- back-end at the point of definition, and may mention
6272 -- entities declared in between (as long as everything is
6273 -- static). It is user-friendly to allow unchecked conversions
6276 if Nkind (Original_Node (Nod)) = N_Function_Call then
6277 Set_Etype (Expression (Nod),
6278 Base_Type (Etype (Expression (Nod))));
6279 Set_Etype (Nod, Base_Type (Etype (Nod)));
6282 when N_Function_Call =>
6283 if not Is_Pure (Entity (Name (Nod))) then
6285 ("invalid address clause for initialized object &!",
6289 ("\function & is not pure (RM 13.1(22))!",
6290 Nod, Entity (Name (Nod)));
6293 Check_List_Constants (Parameter_Associations (Nod));
6296 when N_Parameter_Association =>
6297 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
6301 ("invalid address clause for initialized object &!",
6304 ("\must be constant defined before& (RM 13.1(22))!",
6307 end Check_Expr_Constants;
6309 --------------------------
6310 -- Check_List_Constants --
6311 --------------------------
6313 procedure Check_List_Constants (Lst : List_Id) is
6317 if Present (Lst) then
6318 Nod1 := First (Lst);
6319 while Present (Nod1) loop
6320 Check_Expr_Constants (Nod1);
6324 end Check_List_Constants;
6326 -- Start of processing for Check_Constant_Address_Clause
6329 -- If rep_clauses are to be ignored, no need for legality checks. In
6330 -- particular, no need to pester user about rep clauses that violate
6331 -- the rule on constant addresses, given that these clauses will be
6332 -- removed by Freeze before they reach the back end.
6334 if not Ignore_Rep_Clauses then
6335 Check_Expr_Constants (Expr);
6337 end Check_Constant_Address_Clause;
6339 ----------------------------------------
6340 -- Check_Record_Representation_Clause --
6341 ----------------------------------------
6343 procedure Check_Record_Representation_Clause (N : Node_Id) is
6344 Loc : constant Source_Ptr := Sloc (N);
6345 Ident : constant Node_Id := Identifier (N);
6346 Rectype : Entity_Id;
6351 Hbit : Uint := Uint_0;
6355 Max_Bit_So_Far : Uint;
6356 -- Records the maximum bit position so far. If all field positions
6357 -- are monotonically increasing, then we can skip the circuit for
6358 -- checking for overlap, since no overlap is possible.
6360 Tagged_Parent : Entity_Id := Empty;
6361 -- This is set in the case of a derived tagged type for which we have
6362 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
6363 -- positioned by record representation clauses). In this case we must
6364 -- check for overlap between components of this tagged type, and the
6365 -- components of its parent. Tagged_Parent will point to this parent
6366 -- type. For all other cases Tagged_Parent is left set to Empty.
6368 Parent_Last_Bit : Uint;
6369 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
6370 -- last bit position for any field in the parent type. We only need to
6371 -- check overlap for fields starting below this point.
6373 Overlap_Check_Required : Boolean;
6374 -- Used to keep track of whether or not an overlap check is required
6376 Overlap_Detected : Boolean := False;
6377 -- Set True if an overlap is detected
6379 Ccount : Natural := 0;
6380 -- Number of component clauses in record rep clause
6382 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
6383 -- Given two entities for record components or discriminants, checks
6384 -- if they have overlapping component clauses and issues errors if so.
6386 procedure Find_Component;
6387 -- Finds component entity corresponding to current component clause (in
6388 -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin
6389 -- start/stop bits for the field. If there is no matching component or
6390 -- if the matching component does not have a component clause, then
6391 -- that's an error and Comp is set to Empty, but no error message is
6392 -- issued, since the message was already given. Comp is also set to
6393 -- Empty if the current "component clause" is in fact a pragma.
6395 -----------------------------
6396 -- Check_Component_Overlap --
6397 -----------------------------
6399 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
6400 CC1 : constant Node_Id := Component_Clause (C1_Ent);
6401 CC2 : constant Node_Id := Component_Clause (C2_Ent);
6404 if Present (CC1) and then Present (CC2) then
6406 -- Exclude odd case where we have two tag fields in the same
6407 -- record, both at location zero. This seems a bit strange, but
6408 -- it seems to happen in some circumstances, perhaps on an error.
6410 if Chars (C1_Ent) = Name_uTag
6412 Chars (C2_Ent) = Name_uTag
6417 -- Here we check if the two fields overlap
6420 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
6421 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
6422 E1 : constant Uint := S1 + Esize (C1_Ent);
6423 E2 : constant Uint := S2 + Esize (C2_Ent);
6426 if E2 <= S1 or else E1 <= S2 then
6429 Error_Msg_Node_2 := Component_Name (CC2);
6430 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
6431 Error_Msg_Node_1 := Component_Name (CC1);
6433 ("component& overlaps & #", Component_Name (CC1));
6434 Overlap_Detected := True;
6438 end Check_Component_Overlap;
6440 --------------------
6441 -- Find_Component --
6442 --------------------
6444 procedure Find_Component is
6446 procedure Search_Component (R : Entity_Id);
6447 -- Search components of R for a match. If found, Comp is set.
6449 ----------------------
6450 -- Search_Component --
6451 ----------------------
6453 procedure Search_Component (R : Entity_Id) is
6455 Comp := First_Component_Or_Discriminant (R);
6456 while Present (Comp) loop
6458 -- Ignore error of attribute name for component name (we
6459 -- already gave an error message for this, so no need to
6462 if Nkind (Component_Name (CC)) = N_Attribute_Reference then
6465 exit when Chars (Comp) = Chars (Component_Name (CC));
6468 Next_Component_Or_Discriminant (Comp);
6470 end Search_Component;
6472 -- Start of processing for Find_Component
6475 -- Return with Comp set to Empty if we have a pragma
6477 if Nkind (CC) = N_Pragma then
6482 -- Search current record for matching component
6484 Search_Component (Rectype);
6486 -- If not found, maybe component of base type that is absent from
6487 -- statically constrained first subtype.
6490 Search_Component (Base_Type (Rectype));
6493 -- If no component, or the component does not reference the component
6494 -- clause in question, then there was some previous error for which
6495 -- we already gave a message, so just return with Comp Empty.
6498 or else Component_Clause (Comp) /= CC
6502 -- Normal case where we have a component clause
6505 Fbit := Component_Bit_Offset (Comp);
6506 Lbit := Fbit + Esize (Comp) - 1;
6510 -- Start of processing for Check_Record_Representation_Clause
6514 Rectype := Entity (Ident);
6516 if Rectype = Any_Type then
6519 Rectype := Underlying_Type (Rectype);
6522 -- See if we have a fully repped derived tagged type
6525 PS : constant Entity_Id := Parent_Subtype (Rectype);
6528 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
6529 Tagged_Parent := PS;
6531 -- Find maximum bit of any component of the parent type
6533 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
6534 Pcomp := First_Entity (Tagged_Parent);
6535 while Present (Pcomp) loop
6536 if Ekind_In (Pcomp, E_Discriminant, E_Component) then
6537 if Component_Bit_Offset (Pcomp) /= No_Uint
6538 and then Known_Static_Esize (Pcomp)
6543 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
6546 Next_Entity (Pcomp);
6552 -- All done if no component clauses
6554 CC := First (Component_Clauses (N));
6560 -- If a tag is present, then create a component clause that places it
6561 -- at the start of the record (otherwise gigi may place it after other
6562 -- fields that have rep clauses).
6564 Fent := First_Entity (Rectype);
6566 if Nkind (Fent) = N_Defining_Identifier
6567 and then Chars (Fent) = Name_uTag
6569 Set_Component_Bit_Offset (Fent, Uint_0);
6570 Set_Normalized_Position (Fent, Uint_0);
6571 Set_Normalized_First_Bit (Fent, Uint_0);
6572 Set_Normalized_Position_Max (Fent, Uint_0);
6573 Init_Esize (Fent, System_Address_Size);
6575 Set_Component_Clause (Fent,
6576 Make_Component_Clause (Loc,
6577 Component_Name => Make_Identifier (Loc, Name_uTag),
6579 Position => Make_Integer_Literal (Loc, Uint_0),
6580 First_Bit => Make_Integer_Literal (Loc, Uint_0),
6582 Make_Integer_Literal (Loc,
6583 UI_From_Int (System_Address_Size))));
6585 Ccount := Ccount + 1;
6588 Max_Bit_So_Far := Uint_Minus_1;
6589 Overlap_Check_Required := False;
6591 -- Process the component clauses
6593 while Present (CC) loop
6596 if Present (Comp) then
6597 Ccount := Ccount + 1;
6599 -- We need a full overlap check if record positions non-monotonic
6601 if Fbit <= Max_Bit_So_Far then
6602 Overlap_Check_Required := True;
6605 Max_Bit_So_Far := Lbit;
6607 -- Check bit position out of range of specified size
6609 if Has_Size_Clause (Rectype)
6610 and then RM_Size (Rectype) <= Lbit
6613 ("bit number out of range of specified size",
6616 -- Check for overlap with tag field
6619 if Is_Tagged_Type (Rectype)
6620 and then Fbit < System_Address_Size
6623 ("component overlaps tag field of&",
6624 Component_Name (CC), Rectype);
6625 Overlap_Detected := True;
6633 -- Check parent overlap if component might overlap parent field
6635 if Present (Tagged_Parent)
6636 and then Fbit <= Parent_Last_Bit
6638 Pcomp := First_Component_Or_Discriminant (Tagged_Parent);
6639 while Present (Pcomp) loop
6640 if not Is_Tag (Pcomp)
6641 and then Chars (Pcomp) /= Name_uParent
6643 Check_Component_Overlap (Comp, Pcomp);
6646 Next_Component_Or_Discriminant (Pcomp);
6654 -- Now that we have processed all the component clauses, check for
6655 -- overlap. We have to leave this till last, since the components can
6656 -- appear in any arbitrary order in the representation clause.
6658 -- We do not need this check if all specified ranges were monotonic,
6659 -- as recorded by Overlap_Check_Required being False at this stage.
6661 -- This first section checks if there are any overlapping entries at
6662 -- all. It does this by sorting all entries and then seeing if there are
6663 -- any overlaps. If there are none, then that is decisive, but if there
6664 -- are overlaps, they may still be OK (they may result from fields in
6665 -- different variants).
6667 if Overlap_Check_Required then
6668 Overlap_Check1 : declare
6670 OC_Fbit : array (0 .. Ccount) of Uint;
6671 -- First-bit values for component clauses, the value is the offset
6672 -- of the first bit of the field from start of record. The zero
6673 -- entry is for use in sorting.
6675 OC_Lbit : array (0 .. Ccount) of Uint;
6676 -- Last-bit values for component clauses, the value is the offset
6677 -- of the last bit of the field from start of record. The zero
6678 -- entry is for use in sorting.
6680 OC_Count : Natural := 0;
6681 -- Count of entries in OC_Fbit and OC_Lbit
6683 function OC_Lt (Op1, Op2 : Natural) return Boolean;
6684 -- Compare routine for Sort
6686 procedure OC_Move (From : Natural; To : Natural);
6687 -- Move routine for Sort
6689 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
6695 function OC_Lt (Op1, Op2 : Natural) return Boolean is
6697 return OC_Fbit (Op1) < OC_Fbit (Op2);
6704 procedure OC_Move (From : Natural; To : Natural) is
6706 OC_Fbit (To) := OC_Fbit (From);
6707 OC_Lbit (To) := OC_Lbit (From);
6710 -- Start of processing for Overlap_Check
6713 CC := First (Component_Clauses (N));
6714 while Present (CC) loop
6716 -- Exclude component clause already marked in error
6718 if not Error_Posted (CC) then
6721 if Present (Comp) then
6722 OC_Count := OC_Count + 1;
6723 OC_Fbit (OC_Count) := Fbit;
6724 OC_Lbit (OC_Count) := Lbit;
6731 Sorting.Sort (OC_Count);
6733 Overlap_Check_Required := False;
6734 for J in 1 .. OC_Count - 1 loop
6735 if OC_Lbit (J) >= OC_Fbit (J + 1) then
6736 Overlap_Check_Required := True;
6743 -- If Overlap_Check_Required is still True, then we have to do the full
6744 -- scale overlap check, since we have at least two fields that do
6745 -- overlap, and we need to know if that is OK since they are in
6746 -- different variant, or whether we have a definite problem.
6748 if Overlap_Check_Required then
6749 Overlap_Check2 : declare
6750 C1_Ent, C2_Ent : Entity_Id;
6751 -- Entities of components being checked for overlap
6754 -- Component_List node whose Component_Items are being checked
6757 -- Component declaration for component being checked
6760 C1_Ent := First_Entity (Base_Type (Rectype));
6762 -- Loop through all components in record. For each component check
6763 -- for overlap with any of the preceding elements on the component
6764 -- list containing the component and also, if the component is in
6765 -- a variant, check against components outside the case structure.
6766 -- This latter test is repeated recursively up the variant tree.
6768 Main_Component_Loop : while Present (C1_Ent) loop
6769 if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then
6770 goto Continue_Main_Component_Loop;
6773 -- Skip overlap check if entity has no declaration node. This
6774 -- happens with discriminants in constrained derived types.
6775 -- Possibly we are missing some checks as a result, but that
6776 -- does not seem terribly serious.
6778 if No (Declaration_Node (C1_Ent)) then
6779 goto Continue_Main_Component_Loop;
6782 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
6784 -- Loop through component lists that need checking. Check the
6785 -- current component list and all lists in variants above us.
6787 Component_List_Loop : loop
6789 -- If derived type definition, go to full declaration
6790 -- If at outer level, check discriminants if there are any.
6792 if Nkind (Clist) = N_Derived_Type_Definition then
6793 Clist := Parent (Clist);
6796 -- Outer level of record definition, check discriminants
6798 if Nkind_In (Clist, N_Full_Type_Declaration,
6799 N_Private_Type_Declaration)
6801 if Has_Discriminants (Defining_Identifier (Clist)) then
6803 First_Discriminant (Defining_Identifier (Clist));
6804 while Present (C2_Ent) loop
6805 exit when C1_Ent = C2_Ent;
6806 Check_Component_Overlap (C1_Ent, C2_Ent);
6807 Next_Discriminant (C2_Ent);
6811 -- Record extension case
6813 elsif Nkind (Clist) = N_Derived_Type_Definition then
6816 -- Otherwise check one component list
6819 Citem := First (Component_Items (Clist));
6820 while Present (Citem) loop
6821 if Nkind (Citem) = N_Component_Declaration then
6822 C2_Ent := Defining_Identifier (Citem);
6823 exit when C1_Ent = C2_Ent;
6824 Check_Component_Overlap (C1_Ent, C2_Ent);
6831 -- Check for variants above us (the parent of the Clist can
6832 -- be a variant, in which case its parent is a variant part,
6833 -- and the parent of the variant part is a component list
6834 -- whose components must all be checked against the current
6835 -- component for overlap).
6837 if Nkind (Parent (Clist)) = N_Variant then
6838 Clist := Parent (Parent (Parent (Clist)));
6840 -- Check for possible discriminant part in record, this
6841 -- is treated essentially as another level in the
6842 -- recursion. For this case the parent of the component
6843 -- list is the record definition, and its parent is the
6844 -- full type declaration containing the discriminant
6847 elsif Nkind (Parent (Clist)) = N_Record_Definition then
6848 Clist := Parent (Parent ((Clist)));
6850 -- If neither of these two cases, we are at the top of
6854 exit Component_List_Loop;
6856 end loop Component_List_Loop;
6858 <<Continue_Main_Component_Loop>>
6859 Next_Entity (C1_Ent);
6861 end loop Main_Component_Loop;
6865 -- The following circuit deals with warning on record holes (gaps). We
6866 -- skip this check if overlap was detected, since it makes sense for the
6867 -- programmer to fix this illegality before worrying about warnings.
6869 if not Overlap_Detected and Warn_On_Record_Holes then
6870 Record_Hole_Check : declare
6871 Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype));
6872 -- Full declaration of record type
6874 procedure Check_Component_List
6878 -- Check component list CL for holes. The starting bit should be
6879 -- Sbit. which is zero for the main record component list and set
6880 -- appropriately for recursive calls for variants. DS is set to
6881 -- a list of discriminant specifications to be included in the
6882 -- consideration of components. It is No_List if none to consider.
6884 --------------------------
6885 -- Check_Component_List --
6886 --------------------------
6888 procedure Check_Component_List
6896 Compl := Integer (List_Length (Component_Items (CL)));
6898 if DS /= No_List then
6899 Compl := Compl + Integer (List_Length (DS));
6903 Comps : array (Natural range 0 .. Compl) of Entity_Id;
6904 -- Gather components (zero entry is for sort routine)
6906 Ncomps : Natural := 0;
6907 -- Number of entries stored in Comps (starting at Comps (1))
6910 -- One component item or discriminant specification
6913 -- Starting bit for next component
6921 function Lt (Op1, Op2 : Natural) return Boolean;
6922 -- Compare routine for Sort
6924 procedure Move (From : Natural; To : Natural);
6925 -- Move routine for Sort
6927 package Sorting is new GNAT.Heap_Sort_G (Move, Lt);
6933 function Lt (Op1, Op2 : Natural) return Boolean is
6935 return Component_Bit_Offset (Comps (Op1))
6937 Component_Bit_Offset (Comps (Op2));
6944 procedure Move (From : Natural; To : Natural) is
6946 Comps (To) := Comps (From);
6950 -- Gather discriminants into Comp
6952 if DS /= No_List then
6953 Citem := First (DS);
6954 while Present (Citem) loop
6955 if Nkind (Citem) = N_Discriminant_Specification then
6957 Ent : constant Entity_Id :=
6958 Defining_Identifier (Citem);
6960 if Ekind (Ent) = E_Discriminant then
6961 Ncomps := Ncomps + 1;
6962 Comps (Ncomps) := Ent;
6971 -- Gather component entities into Comp
6973 Citem := First (Component_Items (CL));
6974 while Present (Citem) loop
6975 if Nkind (Citem) = N_Component_Declaration then
6976 Ncomps := Ncomps + 1;
6977 Comps (Ncomps) := Defining_Identifier (Citem);
6983 -- Now sort the component entities based on the first bit.
6984 -- Note we already know there are no overlapping components.
6986 Sorting.Sort (Ncomps);
6988 -- Loop through entries checking for holes
6991 for J in 1 .. Ncomps loop
6993 Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit;
6995 if Error_Msg_Uint_1 > 0 then
6997 ("?^-bit gap before component&",
6998 Component_Name (Component_Clause (CEnt)), CEnt);
7001 Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt);
7004 -- Process variant parts recursively if present
7006 if Present (Variant_Part (CL)) then
7007 Variant := First (Variants (Variant_Part (CL)));
7008 while Present (Variant) loop
7009 Check_Component_List
7010 (Component_List (Variant), Nbit, No_List);
7015 end Check_Component_List;
7017 -- Start of processing for Record_Hole_Check
7024 if Is_Tagged_Type (Rectype) then
7025 Sbit := UI_From_Int (System_Address_Size);
7030 if Nkind (Decl) = N_Full_Type_Declaration
7031 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
7033 Check_Component_List
7034 (Component_List (Type_Definition (Decl)),
7036 Discriminant_Specifications (Decl));
7039 end Record_Hole_Check;
7042 -- For records that have component clauses for all components, and whose
7043 -- size is less than or equal to 32, we need to know the size in the
7044 -- front end to activate possible packed array processing where the
7045 -- component type is a record.
7047 -- At this stage Hbit + 1 represents the first unused bit from all the
7048 -- component clauses processed, so if the component clauses are
7049 -- complete, then this is the length of the record.
7051 -- For records longer than System.Storage_Unit, and for those where not
7052 -- all components have component clauses, the back end determines the
7053 -- length (it may for example be appropriate to round up the size
7054 -- to some convenient boundary, based on alignment considerations, etc).
7056 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
7058 -- Nothing to do if at least one component has no component clause
7060 Comp := First_Component_Or_Discriminant (Rectype);
7061 while Present (Comp) loop
7062 exit when No (Component_Clause (Comp));
7063 Next_Component_Or_Discriminant (Comp);
7066 -- If we fall out of loop, all components have component clauses
7067 -- and so we can set the size to the maximum value.
7070 Set_RM_Size (Rectype, Hbit + 1);
7073 end Check_Record_Representation_Clause;
7079 procedure Check_Size
7083 Biased : out Boolean)
7085 UT : constant Entity_Id := Underlying_Type (T);
7091 -- Dismiss cases for generic types or types with previous errors
7094 or else UT = Any_Type
7095 or else Is_Generic_Type (UT)
7096 or else Is_Generic_Type (Root_Type (UT))
7100 -- Check case of bit packed array
7102 elsif Is_Array_Type (UT)
7103 and then Known_Static_Component_Size (UT)
7104 and then Is_Bit_Packed_Array (UT)
7112 Asiz := Component_Size (UT);
7113 Indx := First_Index (UT);
7115 Ityp := Etype (Indx);
7117 -- If non-static bound, then we are not in the business of
7118 -- trying to check the length, and indeed an error will be
7119 -- issued elsewhere, since sizes of non-static array types
7120 -- cannot be set implicitly or explicitly.
7122 if not Is_Static_Subtype (Ityp) then
7126 -- Otherwise accumulate next dimension
7128 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
7129 Expr_Value (Type_Low_Bound (Ityp)) +
7133 exit when No (Indx);
7139 Error_Msg_Uint_1 := Asiz;
7141 ("size for& too small, minimum allowed is ^", N, T);
7142 Set_Esize (T, Asiz);
7143 Set_RM_Size (T, Asiz);
7147 -- All other composite types are ignored
7149 elsif Is_Composite_Type (UT) then
7152 -- For fixed-point types, don't check minimum if type is not frozen,
7153 -- since we don't know all the characteristics of the type that can
7154 -- affect the size (e.g. a specified small) till freeze time.
7156 elsif Is_Fixed_Point_Type (UT)
7157 and then not Is_Frozen (UT)
7161 -- Cases for which a minimum check is required
7164 -- Ignore if specified size is correct for the type
7166 if Known_Esize (UT) and then Siz = Esize (UT) then
7170 -- Otherwise get minimum size
7172 M := UI_From_Int (Minimum_Size (UT));
7176 -- Size is less than minimum size, but one possibility remains
7177 -- that we can manage with the new size if we bias the type.
7179 M := UI_From_Int (Minimum_Size (UT, Biased => True));
7182 Error_Msg_Uint_1 := M;
7184 ("size for& too small, minimum allowed is ^", N, T);
7194 -------------------------
7195 -- Get_Alignment_Value --
7196 -------------------------
7198 function Get_Alignment_Value (Expr : Node_Id) return Uint is
7199 Align : constant Uint := Static_Integer (Expr);
7202 if Align = No_Uint then
7205 elsif Align <= 0 then
7206 Error_Msg_N ("alignment value must be positive", Expr);
7210 for J in Int range 0 .. 64 loop
7212 M : constant Uint := Uint_2 ** J;
7215 exit when M = Align;
7219 ("alignment value must be power of 2", Expr);
7227 end Get_Alignment_Value;
7233 procedure Initialize is
7235 Address_Clause_Checks.Init;
7236 Independence_Checks.Init;
7237 Unchecked_Conversions.Init;
7240 -------------------------
7241 -- Is_Operational_Item --
7242 -------------------------
7244 function Is_Operational_Item (N : Node_Id) return Boolean is
7246 if Nkind (N) /= N_Attribute_Definition_Clause then
7250 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
7252 return Id = Attribute_Input
7253 or else Id = Attribute_Output
7254 or else Id = Attribute_Read
7255 or else Id = Attribute_Write
7256 or else Id = Attribute_External_Tag;
7259 end Is_Operational_Item;
7265 function Minimum_Size
7267 Biased : Boolean := False) return Nat
7269 Lo : Uint := No_Uint;
7270 Hi : Uint := No_Uint;
7271 LoR : Ureal := No_Ureal;
7272 HiR : Ureal := No_Ureal;
7273 LoSet : Boolean := False;
7274 HiSet : Boolean := False;
7278 R_Typ : constant Entity_Id := Root_Type (T);
7281 -- If bad type, return 0
7283 if T = Any_Type then
7286 -- For generic types, just return zero. There cannot be any legitimate
7287 -- need to know such a size, but this routine may be called with a
7288 -- generic type as part of normal processing.
7290 elsif Is_Generic_Type (R_Typ)
7291 or else R_Typ = Any_Type
7295 -- Access types. Normally an access type cannot have a size smaller
7296 -- than the size of System.Address. The exception is on VMS, where
7297 -- we have short and long addresses, and it is possible for an access
7298 -- type to have a short address size (and thus be less than the size
7299 -- of System.Address itself). We simply skip the check for VMS, and
7300 -- leave it to the back end to do the check.
7302 elsif Is_Access_Type (T) then
7303 if OpenVMS_On_Target then
7306 return System_Address_Size;
7309 -- Floating-point types
7311 elsif Is_Floating_Point_Type (T) then
7312 return UI_To_Int (Esize (R_Typ));
7316 elsif Is_Discrete_Type (T) then
7318 -- The following loop is looking for the nearest compile time known
7319 -- bounds following the ancestor subtype chain. The idea is to find
7320 -- the most restrictive known bounds information.
7324 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7329 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
7330 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
7337 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
7338 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
7344 Ancest := Ancestor_Subtype (Ancest);
7347 Ancest := Base_Type (T);
7349 if Is_Generic_Type (Ancest) then
7355 -- Fixed-point types. We can't simply use Expr_Value to get the
7356 -- Corresponding_Integer_Value values of the bounds, since these do not
7357 -- get set till the type is frozen, and this routine can be called
7358 -- before the type is frozen. Similarly the test for bounds being static
7359 -- needs to include the case where we have unanalyzed real literals for
7362 elsif Is_Fixed_Point_Type (T) then
7364 -- The following loop is looking for the nearest compile time known
7365 -- bounds following the ancestor subtype chain. The idea is to find
7366 -- the most restrictive known bounds information.
7370 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
7374 -- Note: In the following two tests for LoSet and HiSet, it may
7375 -- seem redundant to test for N_Real_Literal here since normally
7376 -- one would assume that the test for the value being known at
7377 -- compile time includes this case. However, there is a glitch.
7378 -- If the real literal comes from folding a non-static expression,
7379 -- then we don't consider any non- static expression to be known
7380 -- at compile time if we are in configurable run time mode (needed
7381 -- in some cases to give a clearer definition of what is and what
7382 -- is not accepted). So the test is indeed needed. Without it, we
7383 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
7386 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
7387 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
7389 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
7396 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
7397 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
7399 HiR := Expr_Value_R (Type_High_Bound (Ancest));
7405 Ancest := Ancestor_Subtype (Ancest);
7408 Ancest := Base_Type (T);
7410 if Is_Generic_Type (Ancest) then
7416 Lo := UR_To_Uint (LoR / Small_Value (T));
7417 Hi := UR_To_Uint (HiR / Small_Value (T));
7419 -- No other types allowed
7422 raise Program_Error;
7425 -- Fall through with Hi and Lo set. Deal with biased case
7428 and then not Is_Fixed_Point_Type (T)
7429 and then not (Is_Enumeration_Type (T)
7430 and then Has_Non_Standard_Rep (T)))
7431 or else Has_Biased_Representation (T)
7437 -- Signed case. Note that we consider types like range 1 .. -1 to be
7438 -- signed for the purpose of computing the size, since the bounds have
7439 -- to be accommodated in the base type.
7441 if Lo < 0 or else Hi < 0 then
7445 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
7446 -- Note that we accommodate the case where the bounds cross. This
7447 -- can happen either because of the way the bounds are declared
7448 -- or because of the algorithm in Freeze_Fixed_Point_Type.
7462 -- If both bounds are positive, make sure that both are represen-
7463 -- table in the case where the bounds are crossed. This can happen
7464 -- either because of the way the bounds are declared, or because of
7465 -- the algorithm in Freeze_Fixed_Point_Type.
7471 -- S = size, (can accommodate 0 .. (2**size - 1))
7474 while Hi >= Uint_2 ** S loop
7482 ---------------------------
7483 -- New_Stream_Subprogram --
7484 ---------------------------
7486 procedure New_Stream_Subprogram
7490 Nam : TSS_Name_Type)
7492 Loc : constant Source_Ptr := Sloc (N);
7493 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
7494 Subp_Id : Entity_Id;
7495 Subp_Decl : Node_Id;
7499 Defer_Declaration : constant Boolean :=
7500 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
7501 -- For a tagged type, there is a declaration for each stream attribute
7502 -- at the freeze point, and we must generate only a completion of this
7503 -- declaration. We do the same for private types, because the full view
7504 -- might be tagged. Otherwise we generate a declaration at the point of
7505 -- the attribute definition clause.
7507 function Build_Spec return Node_Id;
7508 -- Used for declaration and renaming declaration, so that this is
7509 -- treated as a renaming_as_body.
7515 function Build_Spec return Node_Id is
7516 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
7519 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
7522 Subp_Id := Make_Defining_Identifier (Loc, Sname);
7524 -- S : access Root_Stream_Type'Class
7526 Formals := New_List (
7527 Make_Parameter_Specification (Loc,
7528 Defining_Identifier =>
7529 Make_Defining_Identifier (Loc, Name_S),
7531 Make_Access_Definition (Loc,
7534 Designated_Type (Etype (F)), Loc))));
7536 if Nam = TSS_Stream_Input then
7537 Spec := Make_Function_Specification (Loc,
7538 Defining_Unit_Name => Subp_Id,
7539 Parameter_Specifications => Formals,
7540 Result_Definition => T_Ref);
7545 Make_Parameter_Specification (Loc,
7546 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
7547 Out_Present => Out_P,
7548 Parameter_Type => T_Ref));
7551 Make_Procedure_Specification (Loc,
7552 Defining_Unit_Name => Subp_Id,
7553 Parameter_Specifications => Formals);
7559 -- Start of processing for New_Stream_Subprogram
7562 F := First_Formal (Subp);
7564 if Ekind (Subp) = E_Procedure then
7565 Etyp := Etype (Next_Formal (F));
7567 Etyp := Etype (Subp);
7570 -- Prepare subprogram declaration and insert it as an action on the
7571 -- clause node. The visibility for this entity is used to test for
7572 -- visibility of the attribute definition clause (in the sense of
7573 -- 8.3(23) as amended by AI-195).
7575 if not Defer_Declaration then
7577 Make_Subprogram_Declaration (Loc,
7578 Specification => Build_Spec);
7580 -- For a tagged type, there is always a visible declaration for each
7581 -- stream TSS (it is a predefined primitive operation), and the
7582 -- completion of this declaration occurs at the freeze point, which is
7583 -- not always visible at places where the attribute definition clause is
7584 -- visible. So, we create a dummy entity here for the purpose of
7585 -- tracking the visibility of the attribute definition clause itself.
7589 Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V'));
7591 Make_Object_Declaration (Loc,
7592 Defining_Identifier => Subp_Id,
7593 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
7596 Insert_Action (N, Subp_Decl);
7597 Set_Entity (N, Subp_Id);
7600 Make_Subprogram_Renaming_Declaration (Loc,
7601 Specification => Build_Spec,
7602 Name => New_Reference_To (Subp, Loc));
7604 if Defer_Declaration then
7605 Set_TSS (Base_Type (Ent), Subp_Id);
7607 Insert_Action (N, Subp_Decl);
7608 Copy_TSS (Subp_Id, Base_Type (Ent));
7610 end New_Stream_Subprogram;
7612 ------------------------
7613 -- Rep_Item_Too_Early --
7614 ------------------------
7616 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
7618 -- Cannot apply non-operational rep items to generic types
7620 if Is_Operational_Item (N) then
7624 and then Is_Generic_Type (Root_Type (T))
7626 Error_Msg_N ("representation item not allowed for generic type", N);
7630 -- Otherwise check for incomplete type
7632 if Is_Incomplete_Or_Private_Type (T)
7633 and then No (Underlying_Type (T))
7635 (Nkind (N) /= N_Pragma
7636 or else Get_Pragma_Id (N) /= Pragma_Import)
7639 ("representation item must be after full type declaration", N);
7642 -- If the type has incomplete components, a representation clause is
7643 -- illegal but stream attributes and Convention pragmas are correct.
7645 elsif Has_Private_Component (T) then
7646 if Nkind (N) = N_Pragma then
7650 ("representation item must appear after type is fully defined",
7657 end Rep_Item_Too_Early;
7659 -----------------------
7660 -- Rep_Item_Too_Late --
7661 -----------------------
7663 function Rep_Item_Too_Late
7666 FOnly : Boolean := False) return Boolean
7669 Parent_Type : Entity_Id;
7672 -- Output the too late message. Note that this is not considered a
7673 -- serious error, since the effect is simply that we ignore the
7674 -- representation clause in this case.
7680 procedure Too_Late is
7682 Error_Msg_N ("|representation item appears too late!", N);
7685 -- Start of processing for Rep_Item_Too_Late
7688 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
7689 -- types, which may be frozen if they appear in a representation clause
7690 -- for a local type.
7693 and then not From_With_Type (T)
7696 S := First_Subtype (T);
7698 if Present (Freeze_Node (S)) then
7700 ("?no more representation items for }", Freeze_Node (S), S);
7705 -- Check for case of non-tagged derived type whose parent either has
7706 -- primitive operations, or is a by reference type (RM 13.1(10)).
7710 and then Is_Derived_Type (T)
7711 and then not Is_Tagged_Type (T)
7713 Parent_Type := Etype (Base_Type (T));
7715 if Has_Primitive_Operations (Parent_Type) then
7718 ("primitive operations already defined for&!", N, Parent_Type);
7721 elsif Is_By_Reference_Type (Parent_Type) then
7724 ("parent type & is a by reference type!", N, Parent_Type);
7729 -- No error, link item into head of chain of rep items for the entity,
7730 -- but avoid chaining if we have an overloadable entity, and the pragma
7731 -- is one that can apply to multiple overloaded entities.
7733 if Is_Overloadable (T)
7734 and then Nkind (N) = N_Pragma
7737 Pname : constant Name_Id := Pragma_Name (N);
7739 if Pname = Name_Convention or else
7740 Pname = Name_Import or else
7741 Pname = Name_Export or else
7742 Pname = Name_External or else
7743 Pname = Name_Interface
7750 Record_Rep_Item (T, N);
7752 end Rep_Item_Too_Late;
7754 -------------------------------------
7755 -- Replace_Type_References_Generic --
7756 -------------------------------------
7758 procedure Replace_Type_References_Generic (N : Node_Id; TName : Name_Id) is
7760 function Replace_Node (N : Node_Id) return Traverse_Result;
7761 -- Processes a single node in the traversal procedure below, checking
7762 -- if node N should be replaced, and if so, doing the replacement.
7764 procedure Replace_Type_Refs is new Traverse_Proc (Replace_Node);
7765 -- This instantiation provides the body of Replace_Type_References
7771 function Replace_Node (N : Node_Id) return Traverse_Result is
7776 -- Case of identifier
7778 if Nkind (N) = N_Identifier then
7780 -- If not the type name, all done with this node
7782 if Chars (N) /= TName then
7785 -- Otherwise do the replacement and we are done with this node
7788 Replace_Type_Reference (N);
7792 -- Case of selected component (which is what a qualification
7793 -- looks like in the unanalyzed tree, which is what we have.
7795 elsif Nkind (N) = N_Selected_Component then
7797 -- If selector name is not our type, keeping going (we might
7798 -- still have an occurrence of the type in the prefix).
7800 if Nkind (Selector_Name (N)) /= N_Identifier
7801 or else Chars (Selector_Name (N)) /= TName
7805 -- Selector name is our type, check qualification
7808 -- Loop through scopes and prefixes, doing comparison
7813 -- Continue if no more scopes or scope with no name
7815 if No (S) or else Nkind (S) not in N_Has_Chars then
7819 -- Do replace if prefix is an identifier matching the
7820 -- scope that we are currently looking at.
7822 if Nkind (P) = N_Identifier
7823 and then Chars (P) = Chars (S)
7825 Replace_Type_Reference (N);
7829 -- Go check scope above us if prefix is itself of the
7830 -- form of a selected component, whose selector matches
7831 -- the scope we are currently looking at.
7833 if Nkind (P) = N_Selected_Component
7834 and then Nkind (Selector_Name (P)) = N_Identifier
7835 and then Chars (Selector_Name (P)) = Chars (S)
7840 -- For anything else, we don't have a match, so keep on
7841 -- going, there are still some weird cases where we may
7842 -- still have a replacement within the prefix.
7850 -- Continue for any other node kind
7858 Replace_Type_Refs (N);
7859 end Replace_Type_References_Generic;
7861 -------------------------
7862 -- Same_Representation --
7863 -------------------------
7865 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
7866 T1 : constant Entity_Id := Underlying_Type (Typ1);
7867 T2 : constant Entity_Id := Underlying_Type (Typ2);
7870 -- A quick check, if base types are the same, then we definitely have
7871 -- the same representation, because the subtype specific representation
7872 -- attributes (Size and Alignment) do not affect representation from
7873 -- the point of view of this test.
7875 if Base_Type (T1) = Base_Type (T2) then
7878 elsif Is_Private_Type (Base_Type (T2))
7879 and then Base_Type (T1) = Full_View (Base_Type (T2))
7884 -- Tagged types never have differing representations
7886 if Is_Tagged_Type (T1) then
7890 -- Representations are definitely different if conventions differ
7892 if Convention (T1) /= Convention (T2) then
7896 -- Representations are different if component alignments differ
7898 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
7900 (Is_Record_Type (T2) or else Is_Array_Type (T2))
7901 and then Component_Alignment (T1) /= Component_Alignment (T2)
7906 -- For arrays, the only real issue is component size. If we know the
7907 -- component size for both arrays, and it is the same, then that's
7908 -- good enough to know we don't have a change of representation.
7910 if Is_Array_Type (T1) then
7911 if Known_Component_Size (T1)
7912 and then Known_Component_Size (T2)
7913 and then Component_Size (T1) = Component_Size (T2)
7915 if VM_Target = No_VM then
7918 -- In VM targets the representation of arrays with aliased
7919 -- components differs from arrays with non-aliased components
7922 return Has_Aliased_Components (Base_Type (T1))
7924 Has_Aliased_Components (Base_Type (T2));
7929 -- Types definitely have same representation if neither has non-standard
7930 -- representation since default representations are always consistent.
7931 -- If only one has non-standard representation, and the other does not,
7932 -- then we consider that they do not have the same representation. They
7933 -- might, but there is no way of telling early enough.
7935 if Has_Non_Standard_Rep (T1) then
7936 if not Has_Non_Standard_Rep (T2) then
7940 return not Has_Non_Standard_Rep (T2);
7943 -- Here the two types both have non-standard representation, and we need
7944 -- to determine if they have the same non-standard representation.
7946 -- For arrays, we simply need to test if the component sizes are the
7947 -- same. Pragma Pack is reflected in modified component sizes, so this
7948 -- check also deals with pragma Pack.
7950 if Is_Array_Type (T1) then
7951 return Component_Size (T1) = Component_Size (T2);
7953 -- Tagged types always have the same representation, because it is not
7954 -- possible to specify different representations for common fields.
7956 elsif Is_Tagged_Type (T1) then
7959 -- Case of record types
7961 elsif Is_Record_Type (T1) then
7963 -- Packed status must conform
7965 if Is_Packed (T1) /= Is_Packed (T2) then
7968 -- Otherwise we must check components. Typ2 maybe a constrained
7969 -- subtype with fewer components, so we compare the components
7970 -- of the base types.
7973 Record_Case : declare
7974 CD1, CD2 : Entity_Id;
7976 function Same_Rep return Boolean;
7977 -- CD1 and CD2 are either components or discriminants. This
7978 -- function tests whether the two have the same representation
7984 function Same_Rep return Boolean is
7986 if No (Component_Clause (CD1)) then
7987 return No (Component_Clause (CD2));
7991 Present (Component_Clause (CD2))
7993 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
7995 Esize (CD1) = Esize (CD2);
7999 -- Start of processing for Record_Case
8002 if Has_Discriminants (T1) then
8003 CD1 := First_Discriminant (T1);
8004 CD2 := First_Discriminant (T2);
8006 -- The number of discriminants may be different if the
8007 -- derived type has fewer (constrained by values). The
8008 -- invisible discriminants retain the representation of
8009 -- the original, so the discrepancy does not per se
8010 -- indicate a different representation.
8013 and then Present (CD2)
8015 if not Same_Rep then
8018 Next_Discriminant (CD1);
8019 Next_Discriminant (CD2);
8024 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
8025 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
8027 while Present (CD1) loop
8028 if not Same_Rep then
8031 Next_Component (CD1);
8032 Next_Component (CD2);
8040 -- For enumeration types, we must check each literal to see if the
8041 -- representation is the same. Note that we do not permit enumeration
8042 -- representation clauses for Character and Wide_Character, so these
8043 -- cases were already dealt with.
8045 elsif Is_Enumeration_Type (T1) then
8046 Enumeration_Case : declare
8050 L1 := First_Literal (T1);
8051 L2 := First_Literal (T2);
8053 while Present (L1) loop
8054 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
8064 end Enumeration_Case;
8066 -- Any other types have the same representation for these purposes
8071 end Same_Representation;
8077 procedure Set_Biased
8081 Biased : Boolean := True)
8085 Set_Has_Biased_Representation (E);
8087 if Warn_On_Biased_Representation then
8089 ("?" & Msg & " forces biased representation for&", N, E);
8094 --------------------
8095 -- Set_Enum_Esize --
8096 --------------------
8098 procedure Set_Enum_Esize (T : Entity_Id) is
8106 -- Find the minimum standard size (8,16,32,64) that fits
8108 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
8109 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
8112 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
8113 Sz := Standard_Character_Size; -- May be > 8 on some targets
8115 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
8118 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
8121 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
8126 if Hi < Uint_2**08 then
8127 Sz := Standard_Character_Size; -- May be > 8 on some targets
8129 elsif Hi < Uint_2**16 then
8132 elsif Hi < Uint_2**32 then
8135 else pragma Assert (Hi < Uint_2**63);
8140 -- That minimum is the proper size unless we have a foreign convention
8141 -- and the size required is 32 or less, in which case we bump the size
8142 -- up to 32. This is required for C and C++ and seems reasonable for
8143 -- all other foreign conventions.
8145 if Has_Foreign_Convention (T)
8146 and then Esize (T) < Standard_Integer_Size
8148 Init_Esize (T, Standard_Integer_Size);
8154 ------------------------------
8155 -- Validate_Address_Clauses --
8156 ------------------------------
8158 procedure Validate_Address_Clauses is
8160 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
8162 ACCR : Address_Clause_Check_Record
8163 renames Address_Clause_Checks.Table (J);
8174 -- Skip processing of this entry if warning already posted
8176 if not Address_Warning_Posted (ACCR.N) then
8178 Expr := Original_Node (Expression (ACCR.N));
8182 X_Alignment := Alignment (ACCR.X);
8183 Y_Alignment := Alignment (ACCR.Y);
8185 -- Similarly obtain sizes
8187 X_Size := Esize (ACCR.X);
8188 Y_Size := Esize (ACCR.Y);
8190 -- Check for large object overlaying smaller one
8193 and then X_Size > Uint_0
8194 and then X_Size > Y_Size
8197 ("?& overlays smaller object", ACCR.N, ACCR.X);
8199 ("\?program execution may be erroneous", ACCR.N);
8200 Error_Msg_Uint_1 := X_Size;
8202 ("\?size of & is ^", ACCR.N, ACCR.X);
8203 Error_Msg_Uint_1 := Y_Size;
8205 ("\?size of & is ^", ACCR.N, ACCR.Y);
8207 -- Check for inadequate alignment, both of the base object
8208 -- and of the offset, if any.
8210 -- Note: we do not check the alignment if we gave a size
8211 -- warning, since it would likely be redundant.
8213 elsif Y_Alignment /= Uint_0
8214 and then (Y_Alignment < X_Alignment
8217 Nkind (Expr) = N_Attribute_Reference
8219 Attribute_Name (Expr) = Name_Address
8221 Has_Compatible_Alignment
8222 (ACCR.X, Prefix (Expr))
8223 /= Known_Compatible))
8226 ("?specified address for& may be inconsistent "
8230 ("\?program execution may be erroneous (RM 13.3(27))",
8232 Error_Msg_Uint_1 := X_Alignment;
8234 ("\?alignment of & is ^",
8236 Error_Msg_Uint_1 := Y_Alignment;
8238 ("\?alignment of & is ^",
8240 if Y_Alignment >= X_Alignment then
8242 ("\?but offset is not multiple of alignment",
8249 end Validate_Address_Clauses;
8251 ---------------------------
8252 -- Validate_Independence --
8253 ---------------------------
8255 procedure Validate_Independence is
8256 SU : constant Uint := UI_From_Int (System_Storage_Unit);
8264 procedure Check_Array_Type (Atyp : Entity_Id);
8265 -- Checks if the array type Atyp has independent components, and
8266 -- if not, outputs an appropriate set of error messages.
8268 procedure No_Independence;
8269 -- Output message that independence cannot be guaranteed
8271 function OK_Component (C : Entity_Id) return Boolean;
8272 -- Checks one component to see if it is independently accessible, and
8273 -- if so yields True, otherwise yields False if independent access
8274 -- cannot be guaranteed. This is a conservative routine, it only
8275 -- returns True if it knows for sure, it returns False if it knows
8276 -- there is a problem, or it cannot be sure there is no problem.
8278 procedure Reason_Bad_Component (C : Entity_Id);
8279 -- Outputs continuation message if a reason can be determined for
8280 -- the component C being bad.
8282 ----------------------
8283 -- Check_Array_Type --
8284 ----------------------
8286 procedure Check_Array_Type (Atyp : Entity_Id) is
8287 Ctyp : constant Entity_Id := Component_Type (Atyp);
8290 -- OK if no alignment clause, no pack, and no component size
8292 if not Has_Component_Size_Clause (Atyp)
8293 and then not Has_Alignment_Clause (Atyp)
8294 and then not Is_Packed (Atyp)
8299 -- Check actual component size
8301 if not Known_Component_Size (Atyp)
8302 or else not (Addressable (Component_Size (Atyp))
8303 and then Component_Size (Atyp) < 64)
8304 or else Component_Size (Atyp) mod Esize (Ctyp) /= 0
8308 -- Bad component size, check reason
8310 if Has_Component_Size_Clause (Atyp) then
8312 Get_Attribute_Definition_Clause
8313 (Atyp, Attribute_Component_Size);
8316 Error_Msg_Sloc := Sloc (P);
8317 Error_Msg_N ("\because of Component_Size clause#", N);
8322 if Is_Packed (Atyp) then
8323 P := Get_Rep_Pragma (Atyp, Name_Pack);
8326 Error_Msg_Sloc := Sloc (P);
8327 Error_Msg_N ("\because of pragma Pack#", N);
8332 -- No reason found, just return
8337 -- Array type is OK independence-wise
8340 end Check_Array_Type;
8342 ---------------------
8343 -- No_Independence --
8344 ---------------------
8346 procedure No_Independence is
8348 if Pragma_Name (N) = Name_Independent then
8350 ("independence cannot be guaranteed for&", N, E);
8353 ("independent components cannot be guaranteed for&", N, E);
8355 end No_Independence;
8361 function OK_Component (C : Entity_Id) return Boolean is
8362 Rec : constant Entity_Id := Scope (C);
8363 Ctyp : constant Entity_Id := Etype (C);
8366 -- OK if no component clause, no Pack, and no alignment clause
8368 if No (Component_Clause (C))
8369 and then not Is_Packed (Rec)
8370 and then not Has_Alignment_Clause (Rec)
8375 -- Here we look at the actual component layout. A component is
8376 -- addressable if its size is a multiple of the Esize of the
8377 -- component type, and its starting position in the record has
8378 -- appropriate alignment, and the record itself has appropriate
8379 -- alignment to guarantee the component alignment.
8381 -- Make sure sizes are static, always assume the worst for any
8382 -- cases where we cannot check static values.
8384 if not (Known_Static_Esize (C)
8385 and then Known_Static_Esize (Ctyp))
8390 -- Size of component must be addressable or greater than 64 bits
8391 -- and a multiple of bytes.
8393 if not Addressable (Esize (C))
8394 and then Esize (C) < Uint_64
8399 -- Check size is proper multiple
8401 if Esize (C) mod Esize (Ctyp) /= 0 then
8405 -- Check alignment of component is OK
8407 if not Known_Component_Bit_Offset (C)
8408 or else Component_Bit_Offset (C) < Uint_0
8409 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0
8414 -- Check alignment of record type is OK
8416 if not Known_Alignment (Rec)
8417 or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8422 -- All tests passed, component is addressable
8427 --------------------------
8428 -- Reason_Bad_Component --
8429 --------------------------
8431 procedure Reason_Bad_Component (C : Entity_Id) is
8432 Rec : constant Entity_Id := Scope (C);
8433 Ctyp : constant Entity_Id := Etype (C);
8436 -- If component clause present assume that's the problem
8438 if Present (Component_Clause (C)) then
8439 Error_Msg_Sloc := Sloc (Component_Clause (C));
8440 Error_Msg_N ("\because of Component_Clause#", N);
8444 -- If pragma Pack clause present, assume that's the problem
8446 if Is_Packed (Rec) then
8447 P := Get_Rep_Pragma (Rec, Name_Pack);
8450 Error_Msg_Sloc := Sloc (P);
8451 Error_Msg_N ("\because of pragma Pack#", N);
8456 -- See if record has bad alignment clause
8458 if Has_Alignment_Clause (Rec)
8459 and then Known_Alignment (Rec)
8460 and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0
8462 P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment);
8465 Error_Msg_Sloc := Sloc (P);
8466 Error_Msg_N ("\because of Alignment clause#", N);
8470 -- Couldn't find a reason, so return without a message
8473 end Reason_Bad_Component;
8475 -- Start of processing for Validate_Independence
8478 for J in Independence_Checks.First .. Independence_Checks.Last loop
8479 N := Independence_Checks.Table (J).N;
8480 E := Independence_Checks.Table (J).E;
8481 IC := Pragma_Name (N) = Name_Independent_Components;
8483 -- Deal with component case
8485 if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then
8486 if not OK_Component (E) then
8488 Reason_Bad_Component (E);
8493 -- Deal with record with Independent_Components
8495 if IC and then Is_Record_Type (E) then
8496 Comp := First_Component_Or_Discriminant (E);
8497 while Present (Comp) loop
8498 if not OK_Component (Comp) then
8500 Reason_Bad_Component (Comp);
8504 Next_Component_Or_Discriminant (Comp);
8508 -- Deal with address clause case
8510 if Is_Object (E) then
8511 Addr := Address_Clause (E);
8513 if Present (Addr) then
8515 Error_Msg_Sloc := Sloc (Addr);
8516 Error_Msg_N ("\because of Address clause#", N);
8521 -- Deal with independent components for array type
8523 if IC and then Is_Array_Type (E) then
8524 Check_Array_Type (E);
8527 -- Deal with independent components for array object
8529 if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then
8530 Check_Array_Type (Etype (E));
8535 end Validate_Independence;
8537 -----------------------------------
8538 -- Validate_Unchecked_Conversion --
8539 -----------------------------------
8541 procedure Validate_Unchecked_Conversion
8543 Act_Unit : Entity_Id)
8550 -- Obtain source and target types. Note that we call Ancestor_Subtype
8551 -- here because the processing for generic instantiation always makes
8552 -- subtypes, and we want the original frozen actual types.
8554 -- If we are dealing with private types, then do the check on their
8555 -- fully declared counterparts if the full declarations have been
8556 -- encountered (they don't have to be visible, but they must exist!)
8558 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
8560 if Is_Private_Type (Source)
8561 and then Present (Underlying_Type (Source))
8563 Source := Underlying_Type (Source);
8566 Target := Ancestor_Subtype (Etype (Act_Unit));
8568 -- If either type is generic, the instantiation happens within a generic
8569 -- unit, and there is nothing to check. The proper check
8570 -- will happen when the enclosing generic is instantiated.
8572 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
8576 if Is_Private_Type (Target)
8577 and then Present (Underlying_Type (Target))
8579 Target := Underlying_Type (Target);
8582 -- Source may be unconstrained array, but not target
8584 if Is_Array_Type (Target)
8585 and then not Is_Constrained (Target)
8588 ("unchecked conversion to unconstrained array not allowed", N);
8592 -- Warn if conversion between two different convention pointers
8594 if Is_Access_Type (Target)
8595 and then Is_Access_Type (Source)
8596 and then Convention (Target) /= Convention (Source)
8597 and then Warn_On_Unchecked_Conversion
8599 -- Give warnings for subprogram pointers only on most targets. The
8600 -- exception is VMS, where data pointers can have different lengths
8601 -- depending on the pointer convention.
8603 if Is_Access_Subprogram_Type (Target)
8604 or else Is_Access_Subprogram_Type (Source)
8605 or else OpenVMS_On_Target
8608 ("?conversion between pointers with different conventions!", N);
8612 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
8613 -- warning when compiling GNAT-related sources.
8615 if Warn_On_Unchecked_Conversion
8616 and then not In_Predefined_Unit (N)
8617 and then RTU_Loaded (Ada_Calendar)
8619 (Chars (Source) = Name_Time
8621 Chars (Target) = Name_Time)
8623 -- If Ada.Calendar is loaded and the name of one of the operands is
8624 -- Time, there is a good chance that this is Ada.Calendar.Time.
8627 Calendar_Time : constant Entity_Id :=
8628 Full_View (RTE (RO_CA_Time));
8630 pragma Assert (Present (Calendar_Time));
8632 if Source = Calendar_Time
8633 or else Target = Calendar_Time
8636 ("?representation of 'Time values may change between " &
8637 "'G'N'A'T versions", N);
8642 -- Make entry in unchecked conversion table for later processing by
8643 -- Validate_Unchecked_Conversions, which will check sizes and alignments
8644 -- (using values set by the back-end where possible). This is only done
8645 -- if the appropriate warning is active.
8647 if Warn_On_Unchecked_Conversion then
8648 Unchecked_Conversions.Append
8649 (New_Val => UC_Entry'
8654 -- If both sizes are known statically now, then back end annotation
8655 -- is not required to do a proper check but if either size is not
8656 -- known statically, then we need the annotation.
8658 if Known_Static_RM_Size (Source)
8659 and then Known_Static_RM_Size (Target)
8663 Back_Annotate_Rep_Info := True;
8667 -- If unchecked conversion to access type, and access type is declared
8668 -- in the same unit as the unchecked conversion, then set the
8669 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
8672 if Is_Access_Type (Target) and then
8673 In_Same_Source_Unit (Target, N)
8675 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
8678 -- Generate N_Validate_Unchecked_Conversion node for back end in
8679 -- case the back end needs to perform special validation checks.
8681 -- Shouldn't this be in Exp_Ch13, since the check only gets done
8682 -- if we have full expansion and the back end is called ???
8685 Make_Validate_Unchecked_Conversion (Sloc (N));
8686 Set_Source_Type (Vnode, Source);
8687 Set_Target_Type (Vnode, Target);
8689 -- If the unchecked conversion node is in a list, just insert before it.
8690 -- If not we have some strange case, not worth bothering about.
8692 if Is_List_Member (N) then
8693 Insert_After (N, Vnode);
8695 end Validate_Unchecked_Conversion;
8697 ------------------------------------
8698 -- Validate_Unchecked_Conversions --
8699 ------------------------------------
8701 procedure Validate_Unchecked_Conversions is
8703 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
8705 T : UC_Entry renames Unchecked_Conversions.Table (N);
8707 Eloc : constant Source_Ptr := T.Eloc;
8708 Source : constant Entity_Id := T.Source;
8709 Target : constant Entity_Id := T.Target;
8715 -- This validation check, which warns if we have unequal sizes for
8716 -- unchecked conversion, and thus potentially implementation
8717 -- dependent semantics, is one of the few occasions on which we
8718 -- use the official RM size instead of Esize. See description in
8719 -- Einfo "Handling of Type'Size Values" for details.
8721 if Serious_Errors_Detected = 0
8722 and then Known_Static_RM_Size (Source)
8723 and then Known_Static_RM_Size (Target)
8725 -- Don't do the check if warnings off for either type, note the
8726 -- deliberate use of OR here instead of OR ELSE to get the flag
8727 -- Warnings_Off_Used set for both types if appropriate.
8729 and then not (Has_Warnings_Off (Source)
8731 Has_Warnings_Off (Target))
8733 Source_Siz := RM_Size (Source);
8734 Target_Siz := RM_Size (Target);
8736 if Source_Siz /= Target_Siz then
8738 ("?types for unchecked conversion have different sizes!",
8741 if All_Errors_Mode then
8742 Error_Msg_Name_1 := Chars (Source);
8743 Error_Msg_Uint_1 := Source_Siz;
8744 Error_Msg_Name_2 := Chars (Target);
8745 Error_Msg_Uint_2 := Target_Siz;
8746 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
8748 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
8750 if Is_Discrete_Type (Source)
8751 and then Is_Discrete_Type (Target)
8753 if Source_Siz > Target_Siz then
8755 ("\?^ high order bits of source will be ignored!",
8758 elsif Is_Unsigned_Type (Source) then
8760 ("\?source will be extended with ^ high order " &
8761 "zero bits?!", Eloc);
8765 ("\?source will be extended with ^ high order " &
8770 elsif Source_Siz < Target_Siz then
8771 if Is_Discrete_Type (Target) then
8772 if Bytes_Big_Endian then
8774 ("\?target value will include ^ undefined " &
8779 ("\?target value will include ^ undefined " &
8786 ("\?^ trailing bits of target value will be " &
8787 "undefined!", Eloc);
8790 else pragma Assert (Source_Siz > Target_Siz);
8792 ("\?^ trailing bits of source will be ignored!",
8799 -- If both types are access types, we need to check the alignment.
8800 -- If the alignment of both is specified, we can do it here.
8802 if Serious_Errors_Detected = 0
8803 and then Ekind (Source) in Access_Kind
8804 and then Ekind (Target) in Access_Kind
8805 and then Target_Strict_Alignment
8806 and then Present (Designated_Type (Source))
8807 and then Present (Designated_Type (Target))
8810 D_Source : constant Entity_Id := Designated_Type (Source);
8811 D_Target : constant Entity_Id := Designated_Type (Target);
8814 if Known_Alignment (D_Source)
8815 and then Known_Alignment (D_Target)
8818 Source_Align : constant Uint := Alignment (D_Source);
8819 Target_Align : constant Uint := Alignment (D_Target);
8822 if Source_Align < Target_Align
8823 and then not Is_Tagged_Type (D_Source)
8825 -- Suppress warning if warnings suppressed on either
8826 -- type or either designated type. Note the use of
8827 -- OR here instead of OR ELSE. That is intentional,
8828 -- we would like to set flag Warnings_Off_Used in
8829 -- all types for which warnings are suppressed.
8831 and then not (Has_Warnings_Off (D_Source)
8833 Has_Warnings_Off (D_Target)
8835 Has_Warnings_Off (Source)
8837 Has_Warnings_Off (Target))
8839 Error_Msg_Uint_1 := Target_Align;
8840 Error_Msg_Uint_2 := Source_Align;
8841 Error_Msg_Node_1 := D_Target;
8842 Error_Msg_Node_2 := D_Source;
8844 ("?alignment of & (^) is stricter than " &
8845 "alignment of & (^)!", Eloc);
8847 ("\?resulting access value may have invalid " &
8848 "alignment!", Eloc);
8856 end Validate_Unchecked_Conversions;
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