1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, 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 Atree; use Atree;
27 with Checks; use Checks;
28 with Einfo; use Einfo;
29 with Errout; use Errout;
30 with Exp_Tss; use Exp_Tss;
31 with Exp_Util; use Exp_Util;
33 with Lib.Xref; use Lib.Xref;
34 with Namet; use Namet;
35 with Nlists; use Nlists;
36 with Nmake; use Nmake;
38 with Restrict; use Restrict;
39 with Rident; use Rident;
40 with Rtsfind; use Rtsfind;
42 with Sem_Aux; use Sem_Aux;
43 with Sem_Ch8; use Sem_Ch8;
44 with Sem_Eval; use Sem_Eval;
45 with Sem_Res; use Sem_Res;
46 with Sem_Type; use Sem_Type;
47 with Sem_Util; use Sem_Util;
48 with Sem_Warn; use Sem_Warn;
49 with Snames; use Snames;
50 with Stand; use Stand;
51 with Sinfo; use Sinfo;
53 with Targparm; use Targparm;
54 with Ttypes; use Ttypes;
55 with Tbuild; use Tbuild;
56 with Urealp; use Urealp;
58 with GNAT.Heap_Sort_G;
60 package body Sem_Ch13 is
62 SSU : constant Pos := System_Storage_Unit;
63 -- Convenient short hand for commonly used constant
65 -----------------------
66 -- Local Subprograms --
67 -----------------------
69 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id);
70 -- This routine is called after setting the Esize of type entity Typ.
71 -- The purpose is to deal with the situation where an alignment has been
72 -- inherited from a derived type that is no longer appropriate for the
73 -- new Esize value. In this case, we reset the Alignment to unknown.
75 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id);
76 -- Given two entities for record components or discriminants, checks
77 -- if they have overlapping component clauses and issues errors if so.
79 function Get_Alignment_Value (Expr : Node_Id) return Uint;
80 -- Given the expression for an alignment value, returns the corresponding
81 -- Uint value. If the value is inappropriate, then error messages are
82 -- posted as required, and a value of No_Uint is returned.
84 function Is_Operational_Item (N : Node_Id) return Boolean;
85 -- A specification for a stream attribute is allowed before the full
86 -- type is declared, as explained in AI-00137 and the corrigendum.
87 -- Attributes that do not specify a representation characteristic are
88 -- operational attributes.
90 procedure New_Stream_Subprogram
95 -- Create a subprogram renaming of a given stream attribute to the
96 -- designated subprogram and then in the tagged case, provide this as a
97 -- primitive operation, or in the non-tagged case make an appropriate TSS
98 -- entry. This is more properly an expansion activity than just semantics,
99 -- but the presence of user-defined stream functions for limited types is a
100 -- legality check, which is why this takes place here rather than in
101 -- exp_ch13, where it was previously. Nam indicates the name of the TSS
102 -- function to be generated.
104 -- To avoid elaboration anomalies with freeze nodes, for untagged types
105 -- we generate both a subprogram declaration and a subprogram renaming
106 -- declaration, so that the attribute specification is handled as a
107 -- renaming_as_body. For tagged types, the specification is one of the
110 ----------------------------------------------
111 -- Table for Validate_Unchecked_Conversions --
112 ----------------------------------------------
114 -- The following table collects unchecked conversions for validation.
115 -- Entries are made by Validate_Unchecked_Conversion and then the
116 -- call to Validate_Unchecked_Conversions does the actual error
117 -- checking and posting of warnings. The reason for this delayed
118 -- processing is to take advantage of back-annotations of size and
119 -- alignment values performed by the back end.
121 -- Note: the reason we store a Source_Ptr value instead of a Node_Id
122 -- is that by the time Validate_Unchecked_Conversions is called, Sprint
123 -- will already have modified all Sloc values if the -gnatD option is set.
125 type UC_Entry is record
126 Eloc : Source_Ptr; -- node used for posting warnings
127 Source : Entity_Id; -- source type for unchecked conversion
128 Target : Entity_Id; -- target type for unchecked conversion
131 package Unchecked_Conversions is new Table.Table (
132 Table_Component_Type => UC_Entry,
133 Table_Index_Type => Int,
134 Table_Low_Bound => 1,
136 Table_Increment => 200,
137 Table_Name => "Unchecked_Conversions");
139 ----------------------------------------
140 -- Table for Validate_Address_Clauses --
141 ----------------------------------------
143 -- If an address clause has the form
145 -- for X'Address use Expr
147 -- where Expr is of the form Y'Address or recursively is a reference
148 -- to a constant of either of these forms, and X and Y are entities of
149 -- objects, then if Y has a smaller alignment than X, that merits a
150 -- warning about possible bad alignment. The following table collects
151 -- address clauses of this kind. We put these in a table so that they
152 -- can be checked after the back end has completed annotation of the
153 -- alignments of objects, since we can catch more cases that way.
155 type Address_Clause_Check_Record is record
157 -- The address clause
160 -- The entity of the object overlaying Y
163 -- The entity of the object being overlaid
166 -- Whether the address is offseted within Y
169 package Address_Clause_Checks is new Table.Table (
170 Table_Component_Type => Address_Clause_Check_Record,
171 Table_Index_Type => Int,
172 Table_Low_Bound => 1,
174 Table_Increment => 200,
175 Table_Name => "Address_Clause_Checks");
177 -----------------------------------------
178 -- Adjust_Record_For_Reverse_Bit_Order --
179 -----------------------------------------
181 procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is
182 Max_Machine_Scalar_Size : constant Uint :=
184 (Standard_Long_Long_Integer_Size);
185 -- We use this as the maximum machine scalar size in the sense of AI-133
189 SSU : constant Uint := UI_From_Int (System_Storage_Unit);
192 -- This first loop through components does two things. First it deals
193 -- with the case of components with component clauses whose length is
194 -- greater than the maximum machine scalar size (either accepting them
195 -- or rejecting as needed). Second, it counts the number of components
196 -- with component clauses whose length does not exceed this maximum for
200 Comp := First_Component_Or_Discriminant (R);
201 while Present (Comp) loop
203 CC : constant Node_Id := Component_Clause (Comp);
208 Fbit : constant Uint := Static_Integer (First_Bit (CC));
211 -- Case of component with size > max machine scalar
213 if Esize (Comp) > Max_Machine_Scalar_Size then
215 -- Must begin on byte boundary
217 if Fbit mod SSU /= 0 then
219 ("illegal first bit value for reverse bit order",
221 Error_Msg_Uint_1 := SSU;
222 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
225 ("\must be a multiple of ^ if size greater than ^",
228 -- Must end on byte boundary
230 elsif Esize (Comp) mod SSU /= 0 then
232 ("illegal last bit value for reverse bit order",
234 Error_Msg_Uint_1 := SSU;
235 Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
238 ("\must be a multiple of ^ if size greater than ^",
241 -- OK, give warning if enabled
243 elsif Warn_On_Reverse_Bit_Order then
245 ("multi-byte field specified with non-standard"
246 & " Bit_Order?", CC);
248 if Bytes_Big_Endian then
250 ("\bytes are not reversed "
251 & "(component is big-endian)?", CC);
254 ("\bytes are not reversed "
255 & "(component is little-endian)?", CC);
259 -- Case where size is not greater than max machine
260 -- scalar. For now, we just count these.
263 Num_CC := Num_CC + 1;
269 Next_Component_Or_Discriminant (Comp);
272 -- We need to sort the component clauses on the basis of the Position
273 -- values in the clause, so we can group clauses with the same Position.
274 -- together to determine the relevant machine scalar size.
277 Comps : array (0 .. Num_CC) of Entity_Id;
278 -- Array to collect component and discriminant entities. The data
279 -- starts at index 1, the 0'th entry is for the sort routine.
281 function CP_Lt (Op1, Op2 : Natural) return Boolean;
282 -- Compare routine for Sort
284 procedure CP_Move (From : Natural; To : Natural);
285 -- Move routine for Sort
287 package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt);
291 -- Start and stop positions in component list of set of components
292 -- with the same starting position (that constitute components in
293 -- a single machine scalar).
296 -- Maximum last bit value of any component in this set
299 -- Corresponding machine scalar size
305 function CP_Lt (Op1, Op2 : Natural) return Boolean is
307 return Position (Component_Clause (Comps (Op1))) <
308 Position (Component_Clause (Comps (Op2)));
315 procedure CP_Move (From : Natural; To : Natural) is
317 Comps (To) := Comps (From);
321 -- Collect the component clauses
324 Comp := First_Component_Or_Discriminant (R);
325 while Present (Comp) loop
326 if Present (Component_Clause (Comp))
327 and then Esize (Comp) <= Max_Machine_Scalar_Size
329 Num_CC := Num_CC + 1;
330 Comps (Num_CC) := Comp;
333 Next_Component_Or_Discriminant (Comp);
336 -- Sort by ascending position number
338 Sorting.Sort (Num_CC);
340 -- We now have all the components whose size does not exceed the max
341 -- machine scalar value, sorted by starting position. In this loop
342 -- we gather groups of clauses starting at the same position, to
343 -- process them in accordance with Ada 2005 AI-133.
346 while Stop < Num_CC loop
350 Static_Integer (Last_Bit (Component_Clause (Comps (Start))));
351 while Stop < Num_CC loop
353 (Position (Component_Clause (Comps (Stop + 1)))) =
355 (Position (Component_Clause (Comps (Stop))))
362 (Last_Bit (Component_Clause (Comps (Stop)))));
368 -- Now we have a group of component clauses from Start to Stop
369 -- whose positions are identical, and MaxL is the maximum last bit
370 -- value of any of these components.
372 -- We need to determine the corresponding machine scalar size.
373 -- This loop assumes that machine scalar sizes are even, and that
374 -- each possible machine scalar has twice as many bits as the
377 MSS := Max_Machine_Scalar_Size;
379 and then (MSS / 2) >= SSU
380 and then (MSS / 2) > MaxL
385 -- Here is where we fix up the Component_Bit_Offset value to
386 -- account for the reverse bit order. Some examples of what needs
387 -- to be done for the case of a machine scalar size of 8 are:
389 -- First_Bit .. Last_Bit Component_Bit_Offset
401 -- The general rule is that the first bit is obtained by
402 -- subtracting the old ending bit from machine scalar size - 1.
404 for C in Start .. Stop loop
406 Comp : constant Entity_Id := Comps (C);
407 CC : constant Node_Id := Component_Clause (Comp);
408 LB : constant Uint := Static_Integer (Last_Bit (CC));
409 NFB : constant Uint := MSS - Uint_1 - LB;
410 NLB : constant Uint := NFB + Esize (Comp) - 1;
411 Pos : constant Uint := Static_Integer (Position (CC));
414 if Warn_On_Reverse_Bit_Order then
415 Error_Msg_Uint_1 := MSS;
417 ("info: reverse bit order in machine " &
418 "scalar of length^?", First_Bit (CC));
419 Error_Msg_Uint_1 := NFB;
420 Error_Msg_Uint_2 := NLB;
422 if Bytes_Big_Endian then
424 ("?\info: big-endian range for "
425 & "component & is ^ .. ^",
426 First_Bit (CC), Comp);
429 ("?\info: little-endian range "
430 & "for component & is ^ .. ^",
431 First_Bit (CC), Comp);
435 Set_Component_Bit_Offset (Comp, Pos * SSU + NFB);
436 Set_Normalized_First_Bit (Comp, NFB mod SSU);
441 end Adjust_Record_For_Reverse_Bit_Order;
443 --------------------------------------
444 -- Alignment_Check_For_Esize_Change --
445 --------------------------------------
447 procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id) is
449 -- If the alignment is known, and not set by a rep clause, and is
450 -- inconsistent with the size being set, then reset it to unknown,
451 -- we assume in this case that the size overrides the inherited
452 -- alignment, and that the alignment must be recomputed.
454 if Known_Alignment (Typ)
455 and then not Has_Alignment_Clause (Typ)
456 and then Esize (Typ) mod (Alignment (Typ) * SSU) /= 0
458 Init_Alignment (Typ);
460 end Alignment_Check_For_Esize_Change;
462 -----------------------
463 -- Analyze_At_Clause --
464 -----------------------
466 -- An at clause is replaced by the corresponding Address attribute
467 -- definition clause that is the preferred approach in Ada 95.
469 procedure Analyze_At_Clause (N : Node_Id) is
470 CS : constant Boolean := Comes_From_Source (N);
473 -- This is an obsolescent feature
475 Check_Restriction (No_Obsolescent_Features, N);
477 if Warn_On_Obsolescent_Feature then
479 ("at clause is an obsolescent feature (RM J.7(2))?", N);
481 ("\use address attribute definition clause instead?", N);
484 -- Rewrite as address clause
487 Make_Attribute_Definition_Clause (Sloc (N),
488 Name => Identifier (N),
489 Chars => Name_Address,
490 Expression => Expression (N)));
492 -- We preserve Comes_From_Source, since logically the clause still
493 -- comes from the source program even though it is changed in form.
495 Set_Comes_From_Source (N, CS);
497 -- Analyze rewritten clause
499 Analyze_Attribute_Definition_Clause (N);
500 end Analyze_At_Clause;
502 -----------------------------------------
503 -- Analyze_Attribute_Definition_Clause --
504 -----------------------------------------
506 procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is
507 Loc : constant Source_Ptr := Sloc (N);
508 Nam : constant Node_Id := Name (N);
509 Attr : constant Name_Id := Chars (N);
510 Expr : constant Node_Id := Expression (N);
511 Id : constant Attribute_Id := Get_Attribute_Id (Attr);
515 FOnly : Boolean := False;
516 -- Reset to True for subtype specific attribute (Alignment, Size)
517 -- and for stream attributes, i.e. those cases where in the call
518 -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing
519 -- rules are checked. Note that the case of stream attributes is not
520 -- clear from the RM, but see AI95-00137. Also, the RM seems to
521 -- disallow Storage_Size for derived task types, but that is also
522 -- clearly unintentional.
524 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type);
525 -- Common processing for 'Read, 'Write, 'Input and 'Output attribute
526 -- definition clauses.
528 -----------------------------------
529 -- Analyze_Stream_TSS_Definition --
530 -----------------------------------
532 procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is
533 Subp : Entity_Id := Empty;
538 Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read);
540 function Has_Good_Profile (Subp : Entity_Id) return Boolean;
541 -- Return true if the entity is a subprogram with an appropriate
542 -- profile for the attribute being defined.
544 ----------------------
545 -- Has_Good_Profile --
546 ----------------------
548 function Has_Good_Profile (Subp : Entity_Id) return Boolean is
550 Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input);
551 Expected_Ekind : constant array (Boolean) of Entity_Kind :=
552 (False => E_Procedure, True => E_Function);
556 if Ekind (Subp) /= Expected_Ekind (Is_Function) then
560 F := First_Formal (Subp);
563 or else Ekind (Etype (F)) /= E_Anonymous_Access_Type
564 or else Designated_Type (Etype (F)) /=
565 Class_Wide_Type (RTE (RE_Root_Stream_Type))
570 if not Is_Function then
574 Expected_Mode : constant array (Boolean) of Entity_Kind :=
575 (False => E_In_Parameter,
576 True => E_Out_Parameter);
578 if Parameter_Mode (F) /= Expected_Mode (Is_Read) then
589 return Base_Type (Typ) = Base_Type (Ent)
590 and then No (Next_Formal (F));
591 end Has_Good_Profile;
593 -- Start of processing for Analyze_Stream_TSS_Definition
598 if not Is_Type (U_Ent) then
599 Error_Msg_N ("local name must be a subtype", Nam);
603 Pnam := TSS (Base_Type (U_Ent), TSS_Nam);
605 -- If Pnam is present, it can be either inherited from an ancestor
606 -- type (in which case it is legal to redefine it for this type), or
607 -- be a previous definition of the attribute for the same type (in
608 -- which case it is illegal).
610 -- In the first case, it will have been analyzed already, and we
611 -- can check that its profile does not match the expected profile
612 -- for a stream attribute of U_Ent. In the second case, either Pnam
613 -- has been analyzed (and has the expected profile), or it has not
614 -- been analyzed yet (case of a type that has not been frozen yet
615 -- and for which the stream attribute has been set using Set_TSS).
618 and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam))
620 Error_Msg_Sloc := Sloc (Pnam);
621 Error_Msg_Name_1 := Attr;
622 Error_Msg_N ("% attribute already defined #", Nam);
628 if Is_Entity_Name (Expr) then
629 if not Is_Overloaded (Expr) then
630 if Has_Good_Profile (Entity (Expr)) then
631 Subp := Entity (Expr);
635 Get_First_Interp (Expr, I, It);
636 while Present (It.Nam) loop
637 if Has_Good_Profile (It.Nam) then
642 Get_Next_Interp (I, It);
647 if Present (Subp) then
648 if Is_Abstract_Subprogram (Subp) then
649 Error_Msg_N ("stream subprogram must not be abstract", Expr);
653 Set_Entity (Expr, Subp);
654 Set_Etype (Expr, Etype (Subp));
656 New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam);
659 Error_Msg_Name_1 := Attr;
660 Error_Msg_N ("incorrect expression for% attribute", Expr);
662 end Analyze_Stream_TSS_Definition;
664 -- Start of processing for Analyze_Attribute_Definition_Clause
667 -- Process Ignore_Rep_Clauses option
669 if Ignore_Rep_Clauses then
672 -- The following should be ignored. They do not affect legality
673 -- and may be target dependent. The basic idea of -gnatI is to
674 -- ignore any rep clauses that may be target dependent but do not
675 -- affect legality (except possibly to be rejected because they
676 -- are incompatible with the compilation target).
678 when Attribute_Address |
679 Attribute_Alignment |
680 Attribute_Bit_Order |
681 Attribute_Component_Size |
682 Attribute_Machine_Radix |
683 Attribute_Object_Size |
686 Attribute_Stream_Size |
687 Attribute_Value_Size =>
689 Rewrite (N, Make_Null_Statement (Sloc (N)));
692 -- The following should not be ignored, because in the first place
693 -- they are reasonably portable, and should not cause problems in
694 -- compiling code from another target, and also they do affect
695 -- legality, e.g. failing to provide a stream attribute for a
696 -- type may make a program illegal.
698 when Attribute_External_Tag |
702 Attribute_Storage_Pool |
703 Attribute_Storage_Size |
707 -- Other cases are errors, which will be caught below
717 if Rep_Item_Too_Early (Ent, N) then
721 -- Rep clause applies to full view of incomplete type or private type if
722 -- we have one (if not, this is a premature use of the type). However,
723 -- certain semantic checks need to be done on the specified entity (i.e.
724 -- the private view), so we save it in Ent.
726 if Is_Private_Type (Ent)
727 and then Is_Derived_Type (Ent)
728 and then not Is_Tagged_Type (Ent)
729 and then No (Full_View (Ent))
731 -- If this is a private type whose completion is a derivation from
732 -- another private type, there is no full view, and the attribute
733 -- belongs to the type itself, not its underlying parent.
737 elsif Ekind (Ent) = E_Incomplete_Type then
739 -- The attribute applies to the full view, set the entity of the
740 -- attribute definition accordingly.
742 Ent := Underlying_Type (Ent);
744 Set_Entity (Nam, Ent);
747 U_Ent := Underlying_Type (Ent);
750 -- Complete other routine error checks
752 if Etype (Nam) = Any_Type then
755 elsif Scope (Ent) /= Current_Scope then
756 Error_Msg_N ("entity must be declared in this scope", Nam);
759 elsif No (U_Ent) then
762 elsif Is_Type (U_Ent)
763 and then not Is_First_Subtype (U_Ent)
764 and then Id /= Attribute_Object_Size
765 and then Id /= Attribute_Value_Size
766 and then not From_At_Mod (N)
768 Error_Msg_N ("cannot specify attribute for subtype", Nam);
772 -- Switch on particular attribute
780 -- Address attribute definition clause
782 when Attribute_Address => Address : begin
784 -- A little error check, catch for X'Address use X'Address;
786 if Nkind (Nam) = N_Identifier
787 and then Nkind (Expr) = N_Attribute_Reference
788 and then Attribute_Name (Expr) = Name_Address
789 and then Nkind (Prefix (Expr)) = N_Identifier
790 and then Chars (Nam) = Chars (Prefix (Expr))
793 ("address for & is self-referencing", Prefix (Expr), Ent);
797 -- Not that special case, carry on with analysis of expression
799 Analyze_And_Resolve (Expr, RTE (RE_Address));
801 if Present (Address_Clause (U_Ent)) then
802 Error_Msg_N ("address already given for &", Nam);
804 -- Case of address clause for subprogram
806 elsif Is_Subprogram (U_Ent) then
807 if Has_Homonym (U_Ent) then
809 ("address clause cannot be given " &
810 "for overloaded subprogram",
815 -- For subprograms, all address clauses are permitted, and we
816 -- mark the subprogram as having a deferred freeze so that Gigi
817 -- will not elaborate it too soon.
819 -- Above needs more comments, what is too soon about???
821 Set_Has_Delayed_Freeze (U_Ent);
823 -- Case of address clause for entry
825 elsif Ekind (U_Ent) = E_Entry then
826 if Nkind (Parent (N)) = N_Task_Body then
828 ("entry address must be specified in task spec", Nam);
832 -- For entries, we require a constant address
834 Check_Constant_Address_Clause (Expr, U_Ent);
836 -- Special checks for task types
838 if Is_Task_Type (Scope (U_Ent))
839 and then Comes_From_Source (Scope (U_Ent))
842 ("?entry address declared for entry in task type", N);
844 ("\?only one task can be declared of this type", N);
847 -- Entry address clauses are obsolescent
849 Check_Restriction (No_Obsolescent_Features, N);
851 if Warn_On_Obsolescent_Feature then
853 ("attaching interrupt to task entry is an " &
854 "obsolescent feature (RM J.7.1)?", N);
856 ("\use interrupt procedure instead?", N);
859 -- Case of an address clause for a controlled object which we
860 -- consider to be erroneous.
862 elsif Is_Controlled (Etype (U_Ent))
863 or else Has_Controlled_Component (Etype (U_Ent))
866 ("?controlled object& must not be overlaid", Nam, U_Ent);
868 ("\?Program_Error will be raised at run time", Nam);
869 Insert_Action (Declaration_Node (U_Ent),
870 Make_Raise_Program_Error (Loc,
871 Reason => PE_Overlaid_Controlled_Object));
874 -- Case of address clause for a (non-controlled) object
877 Ekind (U_Ent) = E_Variable
879 Ekind (U_Ent) = E_Constant
882 Expr : constant Node_Id := Expression (N);
887 -- Exported variables cannot have an address clause, because
888 -- this cancels the effect of the pragma Export.
890 if Is_Exported (U_Ent) then
892 ("cannot export object with address clause", Nam);
896 Find_Overlaid_Entity (N, O_Ent, Off);
898 -- Overlaying controlled objects is erroneous
901 and then (Has_Controlled_Component (Etype (O_Ent))
902 or else Is_Controlled (Etype (O_Ent)))
905 ("?cannot overlay with controlled object", Expr);
907 ("\?Program_Error will be raised at run time", Expr);
908 Insert_Action (Declaration_Node (U_Ent),
909 Make_Raise_Program_Error (Loc,
910 Reason => PE_Overlaid_Controlled_Object));
913 elsif Present (O_Ent)
914 and then Ekind (U_Ent) = E_Constant
915 and then not Is_Constant_Object (O_Ent)
917 Error_Msg_N ("constant overlays a variable?", Expr);
919 elsif Present (Renamed_Object (U_Ent)) then
921 ("address clause not allowed"
922 & " for a renaming declaration (RM 13.1(6))", Nam);
925 -- Imported variables can have an address clause, but then
926 -- the import is pretty meaningless except to suppress
927 -- initializations, so we do not need such variables to
928 -- be statically allocated (and in fact it causes trouble
929 -- if the address clause is a local value).
931 elsif Is_Imported (U_Ent) then
932 Set_Is_Statically_Allocated (U_Ent, False);
935 -- We mark a possible modification of a variable with an
936 -- address clause, since it is likely aliasing is occurring.
938 Note_Possible_Modification (Nam, Sure => False);
940 -- Here we are checking for explicit overlap of one variable
941 -- by another, and if we find this then mark the overlapped
942 -- variable as also being volatile to prevent unwanted
943 -- optimizations. This is a significant pessimization so
944 -- avoid it when there is an offset, i.e. when the object
945 -- is composite; they cannot be optimized easily anyway.
948 and then Is_Object (O_Ent)
951 Set_Treat_As_Volatile (O_Ent);
954 -- Legality checks on the address clause for initialized
955 -- objects is deferred until the freeze point, because
956 -- a subsequent pragma might indicate that the object is
957 -- imported and thus not initialized.
959 Set_Has_Delayed_Freeze (U_Ent);
961 -- If an initialization call has been generated for this
962 -- object, it needs to be deferred to after the freeze node
963 -- we have just now added, otherwise GIGI will see a
964 -- reference to the variable (as actual to the IP call)
965 -- before its definition.
968 Init_Call : constant Node_Id := Find_Init_Call (U_Ent, N);
970 if Present (Init_Call) then
972 Append_Freeze_Action (U_Ent, Init_Call);
976 if Is_Exported (U_Ent) then
978 ("& cannot be exported if an address clause is given",
981 ("\define and export a variable " &
982 "that holds its address instead",
986 -- Entity has delayed freeze, so we will generate an
987 -- alignment check at the freeze point unless suppressed.
989 if not Range_Checks_Suppressed (U_Ent)
990 and then not Alignment_Checks_Suppressed (U_Ent)
992 Set_Check_Address_Alignment (N);
995 -- Kill the size check code, since we are not allocating
996 -- the variable, it is somewhere else.
998 Kill_Size_Check_Code (U_Ent);
1000 -- If the address clause is of the form:
1002 -- for Y'Address use X'Address
1006 -- Const : constant Address := X'Address;
1008 -- for Y'Address use Const;
1010 -- then we make an entry in the table for checking the size
1011 -- and alignment of the overlaying variable. We defer this
1012 -- check till after code generation to take full advantage
1013 -- of the annotation done by the back end. This entry is
1014 -- only made if the address clause comes from source.
1016 if Address_Clause_Overlay_Warnings
1017 and then Comes_From_Source (N)
1018 and then Present (O_Ent)
1019 and then Is_Object (O_Ent)
1021 Address_Clause_Checks.Append ((N, U_Ent, O_Ent, Off));
1023 -- If variable overlays a constant view, and we are
1024 -- warning on overlays, then mark the variable as
1025 -- overlaying a constant (we will give warnings later
1026 -- if this variable is assigned).
1028 if Is_Constant_Object (O_Ent)
1029 and then Ekind (U_Ent) = E_Variable
1031 Set_Overlays_Constant (U_Ent);
1036 -- Not a valid entity for an address clause
1039 Error_Msg_N ("address cannot be given for &", Nam);
1047 -- Alignment attribute definition clause
1049 when Attribute_Alignment => Alignment_Block : declare
1050 Align : constant Uint := Get_Alignment_Value (Expr);
1055 if not Is_Type (U_Ent)
1056 and then Ekind (U_Ent) /= E_Variable
1057 and then Ekind (U_Ent) /= E_Constant
1059 Error_Msg_N ("alignment cannot be given for &", Nam);
1061 elsif Has_Alignment_Clause (U_Ent) then
1062 Error_Msg_Sloc := Sloc (Alignment_Clause (U_Ent));
1063 Error_Msg_N ("alignment clause previously given#", N);
1065 elsif Align /= No_Uint then
1066 Set_Has_Alignment_Clause (U_Ent);
1067 Set_Alignment (U_Ent, Align);
1069 end Alignment_Block;
1075 -- Bit_Order attribute definition clause
1077 when Attribute_Bit_Order => Bit_Order : declare
1079 if not Is_Record_Type (U_Ent) then
1081 ("Bit_Order can only be defined for record type", Nam);
1084 Analyze_And_Resolve (Expr, RTE (RE_Bit_Order));
1086 if Etype (Expr) = Any_Type then
1089 elsif not Is_Static_Expression (Expr) then
1090 Flag_Non_Static_Expr
1091 ("Bit_Order requires static expression!", Expr);
1094 if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then
1095 Set_Reverse_Bit_Order (U_Ent, True);
1101 --------------------
1102 -- Component_Size --
1103 --------------------
1105 -- Component_Size attribute definition clause
1107 when Attribute_Component_Size => Component_Size_Case : declare
1108 Csize : constant Uint := Static_Integer (Expr);
1111 New_Ctyp : Entity_Id;
1115 if not Is_Array_Type (U_Ent) then
1116 Error_Msg_N ("component size requires array type", Nam);
1120 Btype := Base_Type (U_Ent);
1122 if Has_Component_Size_Clause (Btype) then
1124 ("component size clause for& previously given", Nam);
1126 elsif Csize /= No_Uint then
1127 Check_Size (Expr, Component_Type (Btype), Csize, Biased);
1129 if Has_Aliased_Components (Btype)
1132 and then Csize /= 16
1135 ("component size incorrect for aliased components", N);
1139 -- For the biased case, build a declaration for a subtype
1140 -- that will be used to represent the biased subtype that
1141 -- reflects the biased representation of components. We need
1142 -- this subtype to get proper conversions on referencing
1143 -- elements of the array. Note that component size clauses
1144 -- are ignored in VM mode.
1146 if VM_Target = No_VM then
1149 Make_Defining_Identifier (Loc,
1151 New_External_Name (Chars (U_Ent), 'C', 0, 'T'));
1154 Make_Subtype_Declaration (Loc,
1155 Defining_Identifier => New_Ctyp,
1156 Subtype_Indication =>
1157 New_Occurrence_Of (Component_Type (Btype), Loc));
1159 Set_Parent (Decl, N);
1160 Analyze (Decl, Suppress => All_Checks);
1162 Set_Has_Delayed_Freeze (New_Ctyp, False);
1163 Set_Esize (New_Ctyp, Csize);
1164 Set_RM_Size (New_Ctyp, Csize);
1165 Init_Alignment (New_Ctyp);
1166 Set_Has_Biased_Representation (New_Ctyp, True);
1167 Set_Is_Itype (New_Ctyp, True);
1168 Set_Associated_Node_For_Itype (New_Ctyp, U_Ent);
1170 Set_Component_Type (Btype, New_Ctyp);
1172 if Warn_On_Biased_Representation then
1174 ("?component size clause forces biased "
1175 & "representation", N);
1179 Set_Component_Size (Btype, Csize);
1181 -- For VM case, we ignore component size clauses
1184 -- Give a warning unless we are in GNAT mode, in which case
1185 -- the warning is suppressed since it is not useful.
1187 if not GNAT_Mode then
1189 ("?component size ignored in this configuration", N);
1193 Set_Has_Component_Size_Clause (Btype, True);
1194 Set_Has_Non_Standard_Rep (Btype, True);
1196 end Component_Size_Case;
1202 when Attribute_External_Tag => External_Tag :
1204 if not Is_Tagged_Type (U_Ent) then
1205 Error_Msg_N ("should be a tagged type", Nam);
1208 Analyze_And_Resolve (Expr, Standard_String);
1210 if not Is_Static_Expression (Expr) then
1211 Flag_Non_Static_Expr
1212 ("static string required for tag name!", Nam);
1215 if VM_Target = No_VM then
1216 Set_Has_External_Tag_Rep_Clause (U_Ent);
1218 Error_Msg_Name_1 := Attr;
1220 ("% attribute unsupported in this configuration", Nam);
1223 if not Is_Library_Level_Entity (U_Ent) then
1225 ("?non-unique external tag supplied for &", N, U_Ent);
1227 ("?\same external tag applies to all subprogram calls", N);
1229 ("?\corresponding internal tag cannot be obtained", N);
1237 when Attribute_Input =>
1238 Analyze_Stream_TSS_Definition (TSS_Stream_Input);
1239 Set_Has_Specified_Stream_Input (Ent);
1245 -- Machine radix attribute definition clause
1247 when Attribute_Machine_Radix => Machine_Radix : declare
1248 Radix : constant Uint := Static_Integer (Expr);
1251 if not Is_Decimal_Fixed_Point_Type (U_Ent) then
1252 Error_Msg_N ("decimal fixed-point type expected for &", Nam);
1254 elsif Has_Machine_Radix_Clause (U_Ent) then
1255 Error_Msg_Sloc := Sloc (Alignment_Clause (U_Ent));
1256 Error_Msg_N ("machine radix clause previously given#", N);
1258 elsif Radix /= No_Uint then
1259 Set_Has_Machine_Radix_Clause (U_Ent);
1260 Set_Has_Non_Standard_Rep (Base_Type (U_Ent));
1264 elsif Radix = 10 then
1265 Set_Machine_Radix_10 (U_Ent);
1267 Error_Msg_N ("machine radix value must be 2 or 10", Expr);
1276 -- Object_Size attribute definition clause
1278 when Attribute_Object_Size => Object_Size : declare
1279 Size : constant Uint := Static_Integer (Expr);
1282 pragma Warnings (Off, Biased);
1285 if not Is_Type (U_Ent) then
1286 Error_Msg_N ("Object_Size cannot be given for &", Nam);
1288 elsif Has_Object_Size_Clause (U_Ent) then
1289 Error_Msg_N ("Object_Size already given for &", Nam);
1292 Check_Size (Expr, U_Ent, Size, Biased);
1300 UI_Mod (Size, 64) /= 0
1303 ("Object_Size must be 8, 16, 32, or multiple of 64",
1307 Set_Esize (U_Ent, Size);
1308 Set_Has_Object_Size_Clause (U_Ent);
1309 Alignment_Check_For_Esize_Change (U_Ent);
1317 when Attribute_Output =>
1318 Analyze_Stream_TSS_Definition (TSS_Stream_Output);
1319 Set_Has_Specified_Stream_Output (Ent);
1325 when Attribute_Read =>
1326 Analyze_Stream_TSS_Definition (TSS_Stream_Read);
1327 Set_Has_Specified_Stream_Read (Ent);
1333 -- Size attribute definition clause
1335 when Attribute_Size => Size : declare
1336 Size : constant Uint := Static_Integer (Expr);
1343 if Has_Size_Clause (U_Ent) then
1344 Error_Msg_N ("size already given for &", Nam);
1346 elsif not Is_Type (U_Ent)
1347 and then Ekind (U_Ent) /= E_Variable
1348 and then Ekind (U_Ent) /= E_Constant
1350 Error_Msg_N ("size cannot be given for &", Nam);
1352 elsif Is_Array_Type (U_Ent)
1353 and then not Is_Constrained (U_Ent)
1356 ("size cannot be given for unconstrained array", Nam);
1358 elsif Size /= No_Uint then
1359 if Is_Type (U_Ent) then
1362 Etyp := Etype (U_Ent);
1365 -- Check size, note that Gigi is in charge of checking that the
1366 -- size of an array or record type is OK. Also we do not check
1367 -- the size in the ordinary fixed-point case, since it is too
1368 -- early to do so (there may be subsequent small clause that
1369 -- affects the size). We can check the size if a small clause
1370 -- has already been given.
1372 if not Is_Ordinary_Fixed_Point_Type (U_Ent)
1373 or else Has_Small_Clause (U_Ent)
1375 Check_Size (Expr, Etyp, Size, Biased);
1376 Set_Has_Biased_Representation (U_Ent, Biased);
1378 if Biased and Warn_On_Biased_Representation then
1380 ("?size clause forces biased representation", N);
1384 -- For types set RM_Size and Esize if possible
1386 if Is_Type (U_Ent) then
1387 Set_RM_Size (U_Ent, Size);
1389 -- For scalar types, increase Object_Size to power of 2, but
1390 -- not less than a storage unit in any case (i.e., normally
1391 -- this means it will be byte addressable).
1393 if Is_Scalar_Type (U_Ent) then
1394 if Size <= System_Storage_Unit then
1395 Init_Esize (U_Ent, System_Storage_Unit);
1396 elsif Size <= 16 then
1397 Init_Esize (U_Ent, 16);
1398 elsif Size <= 32 then
1399 Init_Esize (U_Ent, 32);
1401 Set_Esize (U_Ent, (Size + 63) / 64 * 64);
1404 -- For all other types, object size = value size. The
1405 -- backend will adjust as needed.
1408 Set_Esize (U_Ent, Size);
1411 Alignment_Check_For_Esize_Change (U_Ent);
1413 -- For objects, set Esize only
1416 if Is_Elementary_Type (Etyp) then
1417 if Size /= System_Storage_Unit
1419 Size /= System_Storage_Unit * 2
1421 Size /= System_Storage_Unit * 4
1423 Size /= System_Storage_Unit * 8
1425 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
1426 Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8;
1428 ("size for primitive object must be a power of 2"
1429 & " in the range ^-^", N);
1433 Set_Esize (U_Ent, Size);
1436 Set_Has_Size_Clause (U_Ent);
1444 -- Small attribute definition clause
1446 when Attribute_Small => Small : declare
1447 Implicit_Base : constant Entity_Id := Base_Type (U_Ent);
1451 Analyze_And_Resolve (Expr, Any_Real);
1453 if Etype (Expr) = Any_Type then
1456 elsif not Is_Static_Expression (Expr) then
1457 Flag_Non_Static_Expr
1458 ("small requires static expression!", Expr);
1462 Small := Expr_Value_R (Expr);
1464 if Small <= Ureal_0 then
1465 Error_Msg_N ("small value must be greater than zero", Expr);
1471 if not Is_Ordinary_Fixed_Point_Type (U_Ent) then
1473 ("small requires an ordinary fixed point type", Nam);
1475 elsif Has_Small_Clause (U_Ent) then
1476 Error_Msg_N ("small already given for &", Nam);
1478 elsif Small > Delta_Value (U_Ent) then
1480 ("small value must not be greater then delta value", Nam);
1483 Set_Small_Value (U_Ent, Small);
1484 Set_Small_Value (Implicit_Base, Small);
1485 Set_Has_Small_Clause (U_Ent);
1486 Set_Has_Small_Clause (Implicit_Base);
1487 Set_Has_Non_Standard_Rep (Implicit_Base);
1495 -- Storage_Pool attribute definition clause
1497 when Attribute_Storage_Pool => Storage_Pool : declare
1502 if Ekind (U_Ent) = E_Access_Subprogram_Type then
1504 ("storage pool cannot be given for access-to-subprogram type",
1508 elsif Ekind (U_Ent) /= E_Access_Type
1509 and then Ekind (U_Ent) /= E_General_Access_Type
1512 ("storage pool can only be given for access types", Nam);
1515 elsif Is_Derived_Type (U_Ent) then
1517 ("storage pool cannot be given for a derived access type",
1520 elsif Has_Storage_Size_Clause (U_Ent) then
1521 Error_Msg_N ("storage size already given for &", Nam);
1524 elsif Present (Associated_Storage_Pool (U_Ent)) then
1525 Error_Msg_N ("storage pool already given for &", Nam);
1530 (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool)));
1532 if not Denotes_Variable (Expr) then
1533 Error_Msg_N ("storage pool must be a variable", Expr);
1537 if Nkind (Expr) = N_Type_Conversion then
1538 T := Etype (Expression (Expr));
1543 -- The Stack_Bounded_Pool is used internally for implementing
1544 -- access types with a Storage_Size. Since it only work
1545 -- properly when used on one specific type, we need to check
1546 -- that it is not hijacked improperly:
1547 -- type T is access Integer;
1548 -- for T'Storage_Size use n;
1549 -- type Q is access Float;
1550 -- for Q'Storage_Size use T'Storage_Size; -- incorrect
1552 if RTE_Available (RE_Stack_Bounded_Pool)
1553 and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool)
1555 Error_Msg_N ("non-shareable internal Pool", Expr);
1559 -- If the argument is a name that is not an entity name, then
1560 -- we construct a renaming operation to define an entity of
1561 -- type storage pool.
1563 if not Is_Entity_Name (Expr)
1564 and then Is_Object_Reference (Expr)
1567 Make_Defining_Identifier (Loc,
1568 Chars => New_Internal_Name ('P'));
1571 Rnode : constant Node_Id :=
1572 Make_Object_Renaming_Declaration (Loc,
1573 Defining_Identifier => Pool,
1575 New_Occurrence_Of (Etype (Expr), Loc),
1579 Insert_Before (N, Rnode);
1581 Set_Associated_Storage_Pool (U_Ent, Pool);
1584 elsif Is_Entity_Name (Expr) then
1585 Pool := Entity (Expr);
1587 -- If pool is a renamed object, get original one. This can
1588 -- happen with an explicit renaming, and within instances.
1590 while Present (Renamed_Object (Pool))
1591 and then Is_Entity_Name (Renamed_Object (Pool))
1593 Pool := Entity (Renamed_Object (Pool));
1596 if Present (Renamed_Object (Pool))
1597 and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion
1598 and then Is_Entity_Name (Expression (Renamed_Object (Pool)))
1600 Pool := Entity (Expression (Renamed_Object (Pool)));
1603 Set_Associated_Storage_Pool (U_Ent, Pool);
1605 elsif Nkind (Expr) = N_Type_Conversion
1606 and then Is_Entity_Name (Expression (Expr))
1607 and then Nkind (Original_Node (Expr)) = N_Attribute_Reference
1609 Pool := Entity (Expression (Expr));
1610 Set_Associated_Storage_Pool (U_Ent, Pool);
1613 Error_Msg_N ("incorrect reference to a Storage Pool", Expr);
1622 -- Storage_Size attribute definition clause
1624 when Attribute_Storage_Size => Storage_Size : declare
1625 Btype : constant Entity_Id := Base_Type (U_Ent);
1629 if Is_Task_Type (U_Ent) then
1630 Check_Restriction (No_Obsolescent_Features, N);
1632 if Warn_On_Obsolescent_Feature then
1634 ("storage size clause for task is an " &
1635 "obsolescent feature (RM J.9)?", N);
1637 ("\use Storage_Size pragma instead?", N);
1643 if not Is_Access_Type (U_Ent)
1644 and then Ekind (U_Ent) /= E_Task_Type
1646 Error_Msg_N ("storage size cannot be given for &", Nam);
1648 elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then
1650 ("storage size cannot be given for a derived access type",
1653 elsif Has_Storage_Size_Clause (Btype) then
1654 Error_Msg_N ("storage size already given for &", Nam);
1657 Analyze_And_Resolve (Expr, Any_Integer);
1659 if Is_Access_Type (U_Ent) then
1660 if Present (Associated_Storage_Pool (U_Ent)) then
1661 Error_Msg_N ("storage pool already given for &", Nam);
1665 if Compile_Time_Known_Value (Expr)
1666 and then Expr_Value (Expr) = 0
1668 Set_No_Pool_Assigned (Btype);
1671 else -- Is_Task_Type (U_Ent)
1672 Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size);
1674 if Present (Sprag) then
1675 Error_Msg_Sloc := Sloc (Sprag);
1677 ("Storage_Size already specified#", Nam);
1682 Set_Has_Storage_Size_Clause (Btype);
1690 when Attribute_Stream_Size => Stream_Size : declare
1691 Size : constant Uint := Static_Integer (Expr);
1694 if Ada_Version <= Ada_95 then
1695 Check_Restriction (No_Implementation_Attributes, N);
1698 if Has_Stream_Size_Clause (U_Ent) then
1699 Error_Msg_N ("Stream_Size already given for &", Nam);
1701 elsif Is_Elementary_Type (U_Ent) then
1702 if Size /= System_Storage_Unit
1704 Size /= System_Storage_Unit * 2
1706 Size /= System_Storage_Unit * 4
1708 Size /= System_Storage_Unit * 8
1710 Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit);
1712 ("stream size for elementary type must be a"
1713 & " power of 2 and at least ^", N);
1715 elsif RM_Size (U_Ent) > Size then
1716 Error_Msg_Uint_1 := RM_Size (U_Ent);
1718 ("stream size for elementary type must be a"
1719 & " power of 2 and at least ^", N);
1722 Set_Has_Stream_Size_Clause (U_Ent);
1725 Error_Msg_N ("Stream_Size cannot be given for &", Nam);
1733 -- Value_Size attribute definition clause
1735 when Attribute_Value_Size => Value_Size : declare
1736 Size : constant Uint := Static_Integer (Expr);
1740 if not Is_Type (U_Ent) then
1741 Error_Msg_N ("Value_Size cannot be given for &", Nam);
1744 (Get_Attribute_Definition_Clause
1745 (U_Ent, Attribute_Value_Size))
1747 Error_Msg_N ("Value_Size already given for &", Nam);
1749 elsif Is_Array_Type (U_Ent)
1750 and then not Is_Constrained (U_Ent)
1753 ("Value_Size cannot be given for unconstrained array", Nam);
1756 if Is_Elementary_Type (U_Ent) then
1757 Check_Size (Expr, U_Ent, Size, Biased);
1758 Set_Has_Biased_Representation (U_Ent, Biased);
1760 if Biased and Warn_On_Biased_Representation then
1762 ("?value size clause forces biased representation", N);
1766 Set_RM_Size (U_Ent, Size);
1774 when Attribute_Write =>
1775 Analyze_Stream_TSS_Definition (TSS_Stream_Write);
1776 Set_Has_Specified_Stream_Write (Ent);
1778 -- All other attributes cannot be set
1782 ("attribute& cannot be set with definition clause", N);
1785 -- The test for the type being frozen must be performed after
1786 -- any expression the clause has been analyzed since the expression
1787 -- itself might cause freezing that makes the clause illegal.
1789 if Rep_Item_Too_Late (U_Ent, N, FOnly) then
1792 end Analyze_Attribute_Definition_Clause;
1794 ----------------------------
1795 -- Analyze_Code_Statement --
1796 ----------------------------
1798 procedure Analyze_Code_Statement (N : Node_Id) is
1799 HSS : constant Node_Id := Parent (N);
1800 SBody : constant Node_Id := Parent (HSS);
1801 Subp : constant Entity_Id := Current_Scope;
1808 -- Analyze and check we get right type, note that this implements the
1809 -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that
1810 -- is the only way that Asm_Insn could possibly be visible.
1812 Analyze_And_Resolve (Expression (N));
1814 if Etype (Expression (N)) = Any_Type then
1816 elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then
1817 Error_Msg_N ("incorrect type for code statement", N);
1821 Check_Code_Statement (N);
1823 -- Make sure we appear in the handled statement sequence of a
1824 -- subprogram (RM 13.8(3)).
1826 if Nkind (HSS) /= N_Handled_Sequence_Of_Statements
1827 or else Nkind (SBody) /= N_Subprogram_Body
1830 ("code statement can only appear in body of subprogram", N);
1834 -- Do remaining checks (RM 13.8(3)) if not already done
1836 if not Is_Machine_Code_Subprogram (Subp) then
1837 Set_Is_Machine_Code_Subprogram (Subp);
1839 -- No exception handlers allowed
1841 if Present (Exception_Handlers (HSS)) then
1843 ("exception handlers not permitted in machine code subprogram",
1844 First (Exception_Handlers (HSS)));
1847 -- No declarations other than use clauses and pragmas (we allow
1848 -- certain internally generated declarations as well).
1850 Decl := First (Declarations (SBody));
1851 while Present (Decl) loop
1852 DeclO := Original_Node (Decl);
1853 if Comes_From_Source (DeclO)
1854 and not Nkind_In (DeclO, N_Pragma,
1855 N_Use_Package_Clause,
1857 N_Implicit_Label_Declaration)
1860 ("this declaration not allowed in machine code subprogram",
1867 -- No statements other than code statements, pragmas, and labels.
1868 -- Again we allow certain internally generated statements.
1870 Stmt := First (Statements (HSS));
1871 while Present (Stmt) loop
1872 StmtO := Original_Node (Stmt);
1873 if Comes_From_Source (StmtO)
1874 and then not Nkind_In (StmtO, N_Pragma,
1879 ("this statement is not allowed in machine code subprogram",
1886 end Analyze_Code_Statement;
1888 -----------------------------------------------
1889 -- Analyze_Enumeration_Representation_Clause --
1890 -----------------------------------------------
1892 procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is
1893 Ident : constant Node_Id := Identifier (N);
1894 Aggr : constant Node_Id := Array_Aggregate (N);
1895 Enumtype : Entity_Id;
1901 Err : Boolean := False;
1903 Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer));
1904 Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer));
1909 if Ignore_Rep_Clauses then
1913 -- First some basic error checks
1916 Enumtype := Entity (Ident);
1918 if Enumtype = Any_Type
1919 or else Rep_Item_Too_Early (Enumtype, N)
1923 Enumtype := Underlying_Type (Enumtype);
1926 if not Is_Enumeration_Type (Enumtype) then
1928 ("enumeration type required, found}",
1929 Ident, First_Subtype (Enumtype));
1933 -- Ignore rep clause on generic actual type. This will already have
1934 -- been flagged on the template as an error, and this is the safest
1935 -- way to ensure we don't get a junk cascaded message in the instance.
1937 if Is_Generic_Actual_Type (Enumtype) then
1940 -- Type must be in current scope
1942 elsif Scope (Enumtype) /= Current_Scope then
1943 Error_Msg_N ("type must be declared in this scope", Ident);
1946 -- Type must be a first subtype
1948 elsif not Is_First_Subtype (Enumtype) then
1949 Error_Msg_N ("cannot give enumeration rep clause for subtype", N);
1952 -- Ignore duplicate rep clause
1954 elsif Has_Enumeration_Rep_Clause (Enumtype) then
1955 Error_Msg_N ("duplicate enumeration rep clause ignored", N);
1958 -- Don't allow rep clause for standard [wide_[wide_]]character
1960 elsif Is_Standard_Character_Type (Enumtype) then
1961 Error_Msg_N ("enumeration rep clause not allowed for this type", N);
1964 -- Check that the expression is a proper aggregate (no parentheses)
1966 elsif Paren_Count (Aggr) /= 0 then
1968 ("extra parentheses surrounding aggregate not allowed",
1972 -- All tests passed, so set rep clause in place
1975 Set_Has_Enumeration_Rep_Clause (Enumtype);
1976 Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype));
1979 -- Now we process the aggregate. Note that we don't use the normal
1980 -- aggregate code for this purpose, because we don't want any of the
1981 -- normal expansion activities, and a number of special semantic
1982 -- rules apply (including the component type being any integer type)
1984 Elit := First_Literal (Enumtype);
1986 -- First the positional entries if any
1988 if Present (Expressions (Aggr)) then
1989 Expr := First (Expressions (Aggr));
1990 while Present (Expr) loop
1992 Error_Msg_N ("too many entries in aggregate", Expr);
1996 Val := Static_Integer (Expr);
1998 -- Err signals that we found some incorrect entries processing
1999 -- the list. The final checks for completeness and ordering are
2000 -- skipped in this case.
2002 if Val = No_Uint then
2004 elsif Val < Lo or else Hi < Val then
2005 Error_Msg_N ("value outside permitted range", Expr);
2009 Set_Enumeration_Rep (Elit, Val);
2010 Set_Enumeration_Rep_Expr (Elit, Expr);
2016 -- Now process the named entries if present
2018 if Present (Component_Associations (Aggr)) then
2019 Assoc := First (Component_Associations (Aggr));
2020 while Present (Assoc) loop
2021 Choice := First (Choices (Assoc));
2023 if Present (Next (Choice)) then
2025 ("multiple choice not allowed here", Next (Choice));
2029 if Nkind (Choice) = N_Others_Choice then
2030 Error_Msg_N ("others choice not allowed here", Choice);
2033 elsif Nkind (Choice) = N_Range then
2034 -- ??? should allow zero/one element range here
2035 Error_Msg_N ("range not allowed here", Choice);
2039 Analyze_And_Resolve (Choice, Enumtype);
2041 if Is_Entity_Name (Choice)
2042 and then Is_Type (Entity (Choice))
2044 Error_Msg_N ("subtype name not allowed here", Choice);
2046 -- ??? should allow static subtype with zero/one entry
2048 elsif Etype (Choice) = Base_Type (Enumtype) then
2049 if not Is_Static_Expression (Choice) then
2050 Flag_Non_Static_Expr
2051 ("non-static expression used for choice!", Choice);
2055 Elit := Expr_Value_E (Choice);
2057 if Present (Enumeration_Rep_Expr (Elit)) then
2058 Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit));
2060 ("representation for& previously given#",
2065 Set_Enumeration_Rep_Expr (Elit, Choice);
2067 Expr := Expression (Assoc);
2068 Val := Static_Integer (Expr);
2070 if Val = No_Uint then
2073 elsif Val < Lo or else Hi < Val then
2074 Error_Msg_N ("value outside permitted range", Expr);
2078 Set_Enumeration_Rep (Elit, Val);
2087 -- Aggregate is fully processed. Now we check that a full set of
2088 -- representations was given, and that they are in range and in order.
2089 -- These checks are only done if no other errors occurred.
2095 Elit := First_Literal (Enumtype);
2096 while Present (Elit) loop
2097 if No (Enumeration_Rep_Expr (Elit)) then
2098 Error_Msg_NE ("missing representation for&!", N, Elit);
2101 Val := Enumeration_Rep (Elit);
2103 if Min = No_Uint then
2107 if Val /= No_Uint then
2108 if Max /= No_Uint and then Val <= Max then
2110 ("enumeration value for& not ordered!",
2111 Enumeration_Rep_Expr (Elit), Elit);
2117 -- If there is at least one literal whose representation
2118 -- is not equal to the Pos value, then note that this
2119 -- enumeration type has a non-standard representation.
2121 if Val /= Enumeration_Pos (Elit) then
2122 Set_Has_Non_Standard_Rep (Base_Type (Enumtype));
2129 -- Now set proper size information
2132 Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype));
2135 if Has_Size_Clause (Enumtype) then
2136 if Esize (Enumtype) >= Minsize then
2141 UI_From_Int (Minimum_Size (Enumtype, Biased => True));
2143 if Esize (Enumtype) < Minsize then
2144 Error_Msg_N ("previously given size is too small", N);
2147 Set_Has_Biased_Representation (Enumtype);
2152 Set_RM_Size (Enumtype, Minsize);
2153 Set_Enum_Esize (Enumtype);
2156 Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype));
2157 Set_Esize (Base_Type (Enumtype), Esize (Enumtype));
2158 Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype));
2162 -- We repeat the too late test in case it froze itself!
2164 if Rep_Item_Too_Late (Enumtype, N) then
2167 end Analyze_Enumeration_Representation_Clause;
2169 ----------------------------
2170 -- Analyze_Free_Statement --
2171 ----------------------------
2173 procedure Analyze_Free_Statement (N : Node_Id) is
2175 Analyze (Expression (N));
2176 end Analyze_Free_Statement;
2178 ------------------------------------------
2179 -- Analyze_Record_Representation_Clause --
2180 ------------------------------------------
2182 procedure Analyze_Record_Representation_Clause (N : Node_Id) is
2183 Loc : constant Source_Ptr := Sloc (N);
2184 Ident : constant Node_Id := Identifier (N);
2185 Rectype : Entity_Id;
2191 Hbit : Uint := Uint_0;
2197 Max_Bit_So_Far : Uint;
2198 -- Records the maximum bit position so far. If all field positions
2199 -- are monotonically increasing, then we can skip the circuit for
2200 -- checking for overlap, since no overlap is possible.
2202 Tagged_Parent : Entity_Id := Empty;
2203 -- This is set in the case of a derived tagged type for which we have
2204 -- Is_Fully_Repped_Tagged_Type True (indicating that all components are
2205 -- positioned by record representation clauses). In this case we must
2206 -- check for overlap between components of this tagged type, and the
2207 -- components of its parent. Tagged_Parent will point to this parent
2208 -- type. For all other cases Tagged_Parent is left set to Empty.
2210 Parent_Last_Bit : Uint;
2211 -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the
2212 -- last bit position for any field in the parent type. We only need to
2213 -- check overlap for fields starting below this point.
2215 Overlap_Check_Required : Boolean;
2216 -- Used to keep track of whether or not an overlap check is required
2218 Ccount : Natural := 0;
2219 -- Number of component clauses in record rep clause
2221 CR_Pragma : Node_Id := Empty;
2222 -- Points to N_Pragma node if Complete_Representation pragma present
2225 if Ignore_Rep_Clauses then
2230 Rectype := Entity (Ident);
2232 if Rectype = Any_Type
2233 or else Rep_Item_Too_Early (Rectype, N)
2237 Rectype := Underlying_Type (Rectype);
2240 -- First some basic error checks
2242 if not Is_Record_Type (Rectype) then
2244 ("record type required, found}", Ident, First_Subtype (Rectype));
2247 elsif Is_Unchecked_Union (Rectype) then
2249 ("record rep clause not allowed for Unchecked_Union", N);
2251 elsif Scope (Rectype) /= Current_Scope then
2252 Error_Msg_N ("type must be declared in this scope", N);
2255 elsif not Is_First_Subtype (Rectype) then
2256 Error_Msg_N ("cannot give record rep clause for subtype", N);
2259 elsif Has_Record_Rep_Clause (Rectype) then
2260 Error_Msg_N ("duplicate record rep clause ignored", N);
2263 elsif Rep_Item_Too_Late (Rectype, N) then
2267 if Present (Mod_Clause (N)) then
2269 Loc : constant Source_Ptr := Sloc (N);
2270 M : constant Node_Id := Mod_Clause (N);
2271 P : constant List_Id := Pragmas_Before (M);
2275 pragma Warnings (Off, Mod_Val);
2278 Check_Restriction (No_Obsolescent_Features, Mod_Clause (N));
2280 if Warn_On_Obsolescent_Feature then
2282 ("mod clause is an obsolescent feature (RM J.8)?", N);
2284 ("\use alignment attribute definition clause instead?", N);
2291 -- In ASIS_Mode mode, expansion is disabled, but we must convert
2292 -- the Mod clause into an alignment clause anyway, so that the
2293 -- back-end can compute and back-annotate properly the size and
2294 -- alignment of types that may include this record.
2296 -- This seems dubious, this destroys the source tree in a manner
2297 -- not detectable by ASIS ???
2299 if Operating_Mode = Check_Semantics
2303 Make_Attribute_Definition_Clause (Loc,
2304 Name => New_Reference_To (Base_Type (Rectype), Loc),
2305 Chars => Name_Alignment,
2306 Expression => Relocate_Node (Expression (M)));
2308 Set_From_At_Mod (AtM_Nod);
2309 Insert_After (N, AtM_Nod);
2310 Mod_Val := Get_Alignment_Value (Expression (AtM_Nod));
2311 Set_Mod_Clause (N, Empty);
2314 -- Get the alignment value to perform error checking
2316 Mod_Val := Get_Alignment_Value (Expression (M));
2322 -- For untagged types, clear any existing component clauses for the
2323 -- type. If the type is derived, this is what allows us to override
2324 -- a rep clause for the parent. For type extensions, the representation
2325 -- of the inherited components is inherited, so we want to keep previous
2326 -- component clauses for completeness.
2328 if not Is_Tagged_Type (Rectype) then
2329 Comp := First_Component_Or_Discriminant (Rectype);
2330 while Present (Comp) loop
2331 Set_Component_Clause (Comp, Empty);
2332 Next_Component_Or_Discriminant (Comp);
2336 -- See if we have a fully repped derived tagged type
2339 PS : constant Entity_Id := Parent_Subtype (Rectype);
2342 if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then
2343 Tagged_Parent := PS;
2345 -- Find maximum bit of any component of the parent type
2347 Parent_Last_Bit := UI_From_Int (System_Address_Size - 1);
2348 Pcomp := First_Entity (Tagged_Parent);
2349 while Present (Pcomp) loop
2350 if Ekind (Pcomp) = E_Discriminant
2352 Ekind (Pcomp) = E_Component
2354 if Component_Bit_Offset (Pcomp) /= No_Uint
2355 and then Known_Static_Esize (Pcomp)
2360 Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1);
2363 Next_Entity (Pcomp);
2369 -- All done if no component clauses
2371 CC := First (Component_Clauses (N));
2377 -- If a tag is present, then create a component clause that places it
2378 -- at the start of the record (otherwise gigi may place it after other
2379 -- fields that have rep clauses).
2381 Fent := First_Entity (Rectype);
2383 if Nkind (Fent) = N_Defining_Identifier
2384 and then Chars (Fent) = Name_uTag
2386 Set_Component_Bit_Offset (Fent, Uint_0);
2387 Set_Normalized_Position (Fent, Uint_0);
2388 Set_Normalized_First_Bit (Fent, Uint_0);
2389 Set_Normalized_Position_Max (Fent, Uint_0);
2390 Init_Esize (Fent, System_Address_Size);
2392 Set_Component_Clause (Fent,
2393 Make_Component_Clause (Loc,
2395 Make_Identifier (Loc,
2396 Chars => Name_uTag),
2399 Make_Integer_Literal (Loc,
2403 Make_Integer_Literal (Loc,
2407 Make_Integer_Literal (Loc,
2408 UI_From_Int (System_Address_Size))));
2410 Ccount := Ccount + 1;
2413 -- A representation like this applies to the base type
2415 Set_Has_Record_Rep_Clause (Base_Type (Rectype));
2416 Set_Has_Non_Standard_Rep (Base_Type (Rectype));
2417 Set_Has_Specified_Layout (Base_Type (Rectype));
2419 Max_Bit_So_Far := Uint_Minus_1;
2420 Overlap_Check_Required := False;
2422 -- Process the component clauses
2424 while Present (CC) loop
2428 if Nkind (CC) = N_Pragma then
2431 -- The only pragma of interest is Complete_Representation
2433 if Pragma_Name (CC) = Name_Complete_Representation then
2437 -- Processing for real component clause
2440 Ccount := Ccount + 1;
2441 Posit := Static_Integer (Position (CC));
2442 Fbit := Static_Integer (First_Bit (CC));
2443 Lbit := Static_Integer (Last_Bit (CC));
2446 and then Fbit /= No_Uint
2447 and then Lbit /= No_Uint
2451 ("position cannot be negative", Position (CC));
2455 ("first bit cannot be negative", First_Bit (CC));
2457 -- The Last_Bit specified in a component clause must not be
2458 -- less than the First_Bit minus one (RM-13.5.1(10)).
2460 elsif Lbit < Fbit - 1 then
2462 ("last bit cannot be less than first bit minus one",
2465 -- Values look OK, so find the corresponding record component
2466 -- Even though the syntax allows an attribute reference for
2467 -- implementation-defined components, GNAT does not allow the
2468 -- tag to get an explicit position.
2470 elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then
2471 if Attribute_Name (Component_Name (CC)) = Name_Tag then
2472 Error_Msg_N ("position of tag cannot be specified", CC);
2474 Error_Msg_N ("illegal component name", CC);
2478 Comp := First_Entity (Rectype);
2479 while Present (Comp) loop
2480 exit when Chars (Comp) = Chars (Component_Name (CC));
2486 -- Maybe component of base type that is absent from
2487 -- statically constrained first subtype.
2489 Comp := First_Entity (Base_Type (Rectype));
2490 while Present (Comp) loop
2491 exit when Chars (Comp) = Chars (Component_Name (CC));
2498 ("component clause is for non-existent field", CC);
2500 elsif Present (Component_Clause (Comp)) then
2502 -- Diagnose duplicate rep clause, or check consistency
2503 -- if this is an inherited component. In a double fault,
2504 -- there may be a duplicate inconsistent clause for an
2505 -- inherited component.
2507 if Scope (Original_Record_Component (Comp)) = Rectype
2508 or else Parent (Component_Clause (Comp)) = N
2510 Error_Msg_Sloc := Sloc (Component_Clause (Comp));
2511 Error_Msg_N ("component clause previously given#", CC);
2515 Rep1 : constant Node_Id := Component_Clause (Comp);
2517 if Intval (Position (Rep1)) /=
2518 Intval (Position (CC))
2519 or else Intval (First_Bit (Rep1)) /=
2520 Intval (First_Bit (CC))
2521 or else Intval (Last_Bit (Rep1)) /=
2522 Intval (Last_Bit (CC))
2524 Error_Msg_N ("component clause inconsistent "
2525 & "with representation of ancestor", CC);
2526 elsif Warn_On_Redundant_Constructs then
2527 Error_Msg_N ("?redundant component clause "
2528 & "for inherited component!", CC);
2533 -- Normal case where this is the first component clause we
2534 -- have seen for this entity, so set it up properly.
2537 -- Make reference for field in record rep clause and set
2538 -- appropriate entity field in the field identifier.
2541 (Comp, Component_Name (CC), Set_Ref => False);
2542 Set_Entity (Component_Name (CC), Comp);
2544 -- Update Fbit and Lbit to the actual bit number
2546 Fbit := Fbit + UI_From_Int (SSU) * Posit;
2547 Lbit := Lbit + UI_From_Int (SSU) * Posit;
2549 if Fbit <= Max_Bit_So_Far then
2550 Overlap_Check_Required := True;
2552 Max_Bit_So_Far := Lbit;
2555 if Has_Size_Clause (Rectype)
2556 and then Esize (Rectype) <= Lbit
2559 ("bit number out of range of specified size",
2562 Set_Component_Clause (Comp, CC);
2563 Set_Component_Bit_Offset (Comp, Fbit);
2564 Set_Esize (Comp, 1 + (Lbit - Fbit));
2565 Set_Normalized_First_Bit (Comp, Fbit mod SSU);
2566 Set_Normalized_Position (Comp, Fbit / SSU);
2568 Set_Normalized_Position_Max
2569 (Fent, Normalized_Position (Fent));
2571 if Is_Tagged_Type (Rectype)
2572 and then Fbit < System_Address_Size
2575 ("component overlaps tag field of&",
2576 Component_Name (CC), Rectype);
2579 -- This information is also set in the corresponding
2580 -- component of the base type, found by accessing the
2581 -- Original_Record_Component link if it is present.
2583 Ocomp := Original_Record_Component (Comp);
2590 (Component_Name (CC),
2595 Set_Has_Biased_Representation (Comp, Biased);
2597 if Biased and Warn_On_Biased_Representation then
2599 ("?component clause forces biased "
2600 & "representation", CC);
2603 if Present (Ocomp) then
2604 Set_Component_Clause (Ocomp, CC);
2605 Set_Component_Bit_Offset (Ocomp, Fbit);
2606 Set_Normalized_First_Bit (Ocomp, Fbit mod SSU);
2607 Set_Normalized_Position (Ocomp, Fbit / SSU);
2608 Set_Esize (Ocomp, 1 + (Lbit - Fbit));
2610 Set_Normalized_Position_Max
2611 (Ocomp, Normalized_Position (Ocomp));
2613 Set_Has_Biased_Representation
2614 (Ocomp, Has_Biased_Representation (Comp));
2617 if Esize (Comp) < 0 then
2618 Error_Msg_N ("component size is negative", CC);
2622 -- If OK component size, check parent type overlap if
2623 -- this component might overlap a parent field.
2625 if Present (Tagged_Parent)
2626 and Fbit <= Parent_Last_Bit
2628 Pcomp := First_Entity (Tagged_Parent);
2629 while Present (Pcomp) loop
2630 if (Ekind (Pcomp) = E_Discriminant
2632 Ekind (Pcomp) = E_Component)
2633 and then not Is_Tag (Pcomp)
2634 and then Chars (Pcomp) /= Name_uParent
2636 Check_Component_Overlap (Comp, Pcomp);
2639 Next_Entity (Pcomp);
2650 -- Now that we have processed all the component clauses, check for
2651 -- overlap. We have to leave this till last, since the components can
2652 -- appear in any arbitrary order in the representation clause.
2654 -- We do not need this check if all specified ranges were monotonic,
2655 -- as recorded by Overlap_Check_Required being False at this stage.
2657 -- This first section checks if there are any overlapping entries at
2658 -- all. It does this by sorting all entries and then seeing if there are
2659 -- any overlaps. If there are none, then that is decisive, but if there
2660 -- are overlaps, they may still be OK (they may result from fields in
2661 -- different variants).
2663 if Overlap_Check_Required then
2664 Overlap_Check1 : declare
2666 OC_Fbit : array (0 .. Ccount) of Uint;
2667 -- First-bit values for component clauses, the value is the offset
2668 -- of the first bit of the field from start of record. The zero
2669 -- entry is for use in sorting.
2671 OC_Lbit : array (0 .. Ccount) of Uint;
2672 -- Last-bit values for component clauses, the value is the offset
2673 -- of the last bit of the field from start of record. The zero
2674 -- entry is for use in sorting.
2676 OC_Count : Natural := 0;
2677 -- Count of entries in OC_Fbit and OC_Lbit
2679 function OC_Lt (Op1, Op2 : Natural) return Boolean;
2680 -- Compare routine for Sort
2682 procedure OC_Move (From : Natural; To : Natural);
2683 -- Move routine for Sort
2685 package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt);
2691 function OC_Lt (Op1, Op2 : Natural) return Boolean is
2693 return OC_Fbit (Op1) < OC_Fbit (Op2);
2700 procedure OC_Move (From : Natural; To : Natural) is
2702 OC_Fbit (To) := OC_Fbit (From);
2703 OC_Lbit (To) := OC_Lbit (From);
2706 -- Start of processing for Overlap_Check
2709 CC := First (Component_Clauses (N));
2710 while Present (CC) loop
2711 if Nkind (CC) /= N_Pragma then
2712 Posit := Static_Integer (Position (CC));
2713 Fbit := Static_Integer (First_Bit (CC));
2714 Lbit := Static_Integer (Last_Bit (CC));
2717 and then Fbit /= No_Uint
2718 and then Lbit /= No_Uint
2720 OC_Count := OC_Count + 1;
2721 Posit := Posit * SSU;
2722 OC_Fbit (OC_Count) := Fbit + Posit;
2723 OC_Lbit (OC_Count) := Lbit + Posit;
2730 Sorting.Sort (OC_Count);
2732 Overlap_Check_Required := False;
2733 for J in 1 .. OC_Count - 1 loop
2734 if OC_Lbit (J) >= OC_Fbit (J + 1) then
2735 Overlap_Check_Required := True;
2742 -- If Overlap_Check_Required is still True, then we have to do the full
2743 -- scale overlap check, since we have at least two fields that do
2744 -- overlap, and we need to know if that is OK since they are in
2745 -- different variant, or whether we have a definite problem.
2747 if Overlap_Check_Required then
2748 Overlap_Check2 : declare
2749 C1_Ent, C2_Ent : Entity_Id;
2750 -- Entities of components being checked for overlap
2753 -- Component_List node whose Component_Items are being checked
2756 -- Component declaration for component being checked
2759 C1_Ent := First_Entity (Base_Type (Rectype));
2761 -- Loop through all components in record. For each component check
2762 -- for overlap with any of the preceding elements on the component
2763 -- list containing the component and also, if the component is in
2764 -- a variant, check against components outside the case structure.
2765 -- This latter test is repeated recursively up the variant tree.
2767 Main_Component_Loop : while Present (C1_Ent) loop
2768 if Ekind (C1_Ent) /= E_Component
2769 and then Ekind (C1_Ent) /= E_Discriminant
2771 goto Continue_Main_Component_Loop;
2774 -- Skip overlap check if entity has no declaration node. This
2775 -- happens with discriminants in constrained derived types.
2776 -- Probably we are missing some checks as a result, but that
2777 -- does not seem terribly serious ???
2779 if No (Declaration_Node (C1_Ent)) then
2780 goto Continue_Main_Component_Loop;
2783 Clist := Parent (List_Containing (Declaration_Node (C1_Ent)));
2785 -- Loop through component lists that need checking. Check the
2786 -- current component list and all lists in variants above us.
2788 Component_List_Loop : loop
2790 -- If derived type definition, go to full declaration
2791 -- If at outer level, check discriminants if there are any.
2793 if Nkind (Clist) = N_Derived_Type_Definition then
2794 Clist := Parent (Clist);
2797 -- Outer level of record definition, check discriminants
2799 if Nkind_In (Clist, N_Full_Type_Declaration,
2800 N_Private_Type_Declaration)
2802 if Has_Discriminants (Defining_Identifier (Clist)) then
2804 First_Discriminant (Defining_Identifier (Clist));
2805 while Present (C2_Ent) loop
2806 exit when C1_Ent = C2_Ent;
2807 Check_Component_Overlap (C1_Ent, C2_Ent);
2808 Next_Discriminant (C2_Ent);
2812 -- Record extension case
2814 elsif Nkind (Clist) = N_Derived_Type_Definition then
2817 -- Otherwise check one component list
2820 Citem := First (Component_Items (Clist));
2822 while Present (Citem) loop
2823 if Nkind (Citem) = N_Component_Declaration then
2824 C2_Ent := Defining_Identifier (Citem);
2825 exit when C1_Ent = C2_Ent;
2826 Check_Component_Overlap (C1_Ent, C2_Ent);
2833 -- Check for variants above us (the parent of the Clist can
2834 -- be a variant, in which case its parent is a variant part,
2835 -- and the parent of the variant part is a component list
2836 -- whose components must all be checked against the current
2837 -- component for overlap).
2839 if Nkind (Parent (Clist)) = N_Variant then
2840 Clist := Parent (Parent (Parent (Clist)));
2842 -- Check for possible discriminant part in record, this is
2843 -- treated essentially as another level in the recursion.
2844 -- For this case the parent of the component list is the
2845 -- record definition, and its parent is the full type
2846 -- declaration containing the discriminant specifications.
2848 elsif Nkind (Parent (Clist)) = N_Record_Definition then
2849 Clist := Parent (Parent ((Clist)));
2851 -- If neither of these two cases, we are at the top of
2855 exit Component_List_Loop;
2857 end loop Component_List_Loop;
2859 <<Continue_Main_Component_Loop>>
2860 Next_Entity (C1_Ent);
2862 end loop Main_Component_Loop;
2866 -- For records that have component clauses for all components, and whose
2867 -- size is less than or equal to 32, we need to know the size in the
2868 -- front end to activate possible packed array processing where the
2869 -- component type is a record.
2871 -- At this stage Hbit + 1 represents the first unused bit from all the
2872 -- component clauses processed, so if the component clauses are
2873 -- complete, then this is the length of the record.
2875 -- For records longer than System.Storage_Unit, and for those where not
2876 -- all components have component clauses, the back end determines the
2877 -- length (it may for example be appropriate to round up the size
2878 -- to some convenient boundary, based on alignment considerations, etc).
2880 if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then
2882 -- Nothing to do if at least one component has no component clause
2884 Comp := First_Component_Or_Discriminant (Rectype);
2885 while Present (Comp) loop
2886 exit when No (Component_Clause (Comp));
2887 Next_Component_Or_Discriminant (Comp);
2890 -- If we fall out of loop, all components have component clauses
2891 -- and so we can set the size to the maximum value.
2894 Set_RM_Size (Rectype, Hbit + 1);
2898 -- Check missing components if Complete_Representation pragma appeared
2900 if Present (CR_Pragma) then
2901 Comp := First_Component_Or_Discriminant (Rectype);
2902 while Present (Comp) loop
2903 if No (Component_Clause (Comp)) then
2905 ("missing component clause for &", CR_Pragma, Comp);
2908 Next_Component_Or_Discriminant (Comp);
2911 -- If no Complete_Representation pragma, warn if missing components
2913 elsif Warn_On_Unrepped_Components then
2915 Num_Repped_Components : Nat := 0;
2916 Num_Unrepped_Components : Nat := 0;
2919 -- First count number of repped and unrepped components
2921 Comp := First_Component_Or_Discriminant (Rectype);
2922 while Present (Comp) loop
2923 if Present (Component_Clause (Comp)) then
2924 Num_Repped_Components := Num_Repped_Components + 1;
2926 Num_Unrepped_Components := Num_Unrepped_Components + 1;
2929 Next_Component_Or_Discriminant (Comp);
2932 -- We are only interested in the case where there is at least one
2933 -- unrepped component, and at least half the components have rep
2934 -- clauses. We figure that if less than half have them, then the
2935 -- partial rep clause is really intentional. If the component
2936 -- type has no underlying type set at this point (as for a generic
2937 -- formal type), we don't know enough to give a warning on the
2940 if Num_Unrepped_Components > 0
2941 and then Num_Unrepped_Components < Num_Repped_Components
2943 Comp := First_Component_Or_Discriminant (Rectype);
2944 while Present (Comp) loop
2945 if No (Component_Clause (Comp))
2946 and then Comes_From_Source (Comp)
2947 and then Present (Underlying_Type (Etype (Comp)))
2948 and then (Is_Scalar_Type (Underlying_Type (Etype (Comp)))
2949 or else Size_Known_At_Compile_Time
2950 (Underlying_Type (Etype (Comp))))
2951 and then not Has_Warnings_Off (Rectype)
2953 Error_Msg_Sloc := Sloc (Comp);
2955 ("?no component clause given for & declared #",
2959 Next_Component_Or_Discriminant (Comp);
2964 end Analyze_Record_Representation_Clause;
2966 -----------------------------
2967 -- Check_Component_Overlap --
2968 -----------------------------
2970 procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is
2972 if Present (Component_Clause (C1_Ent))
2973 and then Present (Component_Clause (C2_Ent))
2975 -- Exclude odd case where we have two tag fields in the same record,
2976 -- both at location zero. This seems a bit strange, but it seems to
2977 -- happen in some circumstances ???
2979 if Chars (C1_Ent) = Name_uTag
2980 and then Chars (C2_Ent) = Name_uTag
2985 -- Here we check if the two fields overlap
2988 S1 : constant Uint := Component_Bit_Offset (C1_Ent);
2989 S2 : constant Uint := Component_Bit_Offset (C2_Ent);
2990 E1 : constant Uint := S1 + Esize (C1_Ent);
2991 E2 : constant Uint := S2 + Esize (C2_Ent);
2994 if E2 <= S1 or else E1 <= S2 then
2998 Component_Name (Component_Clause (C2_Ent));
2999 Error_Msg_Sloc := Sloc (Error_Msg_Node_2);
3001 Component_Name (Component_Clause (C1_Ent));
3003 ("component& overlaps & #",
3004 Component_Name (Component_Clause (C1_Ent)));
3008 end Check_Component_Overlap;
3010 -----------------------------------
3011 -- Check_Constant_Address_Clause --
3012 -----------------------------------
3014 procedure Check_Constant_Address_Clause
3018 procedure Check_At_Constant_Address (Nod : Node_Id);
3019 -- Checks that the given node N represents a name whose 'Address is
3020 -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the
3021 -- address value is the same at the point of declaration of U_Ent and at
3022 -- the time of elaboration of the address clause.
3024 procedure Check_Expr_Constants (Nod : Node_Id);
3025 -- Checks that Nod meets the requirements for a constant address clause
3026 -- in the sense of the enclosing procedure.
3028 procedure Check_List_Constants (Lst : List_Id);
3029 -- Check that all elements of list Lst meet the requirements for a
3030 -- constant address clause in the sense of the enclosing procedure.
3032 -------------------------------
3033 -- Check_At_Constant_Address --
3034 -------------------------------
3036 procedure Check_At_Constant_Address (Nod : Node_Id) is
3038 if Is_Entity_Name (Nod) then
3039 if Present (Address_Clause (Entity ((Nod)))) then
3041 ("invalid address clause for initialized object &!",
3044 ("address for& cannot" &
3045 " depend on another address clause! (RM 13.1(22))!",
3048 elsif In_Same_Source_Unit (Entity (Nod), U_Ent)
3049 and then Sloc (U_Ent) < Sloc (Entity (Nod))
3052 ("invalid address clause for initialized object &!",
3054 Error_Msg_Node_2 := U_Ent;
3056 ("\& must be defined before & (RM 13.1(22))!",
3060 elsif Nkind (Nod) = N_Selected_Component then
3062 T : constant Entity_Id := Etype (Prefix (Nod));
3065 if (Is_Record_Type (T)
3066 and then Has_Discriminants (T))
3069 and then Is_Record_Type (Designated_Type (T))
3070 and then Has_Discriminants (Designated_Type (T)))
3073 ("invalid address clause for initialized object &!",
3076 ("\address cannot depend on component" &
3077 " of discriminated record (RM 13.1(22))!",
3080 Check_At_Constant_Address (Prefix (Nod));
3084 elsif Nkind (Nod) = N_Indexed_Component then
3085 Check_At_Constant_Address (Prefix (Nod));
3086 Check_List_Constants (Expressions (Nod));
3089 Check_Expr_Constants (Nod);
3091 end Check_At_Constant_Address;
3093 --------------------------
3094 -- Check_Expr_Constants --
3095 --------------------------
3097 procedure Check_Expr_Constants (Nod : Node_Id) is
3098 Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent);
3099 Ent : Entity_Id := Empty;
3102 if Nkind (Nod) in N_Has_Etype
3103 and then Etype (Nod) = Any_Type
3109 when N_Empty | N_Error =>
3112 when N_Identifier | N_Expanded_Name =>
3113 Ent := Entity (Nod);
3115 -- We need to look at the original node if it is different
3116 -- from the node, since we may have rewritten things and
3117 -- substituted an identifier representing the rewrite.
3119 if Original_Node (Nod) /= Nod then
3120 Check_Expr_Constants (Original_Node (Nod));
3122 -- If the node is an object declaration without initial
3123 -- value, some code has been expanded, and the expression
3124 -- is not constant, even if the constituents might be
3125 -- acceptable, as in A'Address + offset.
3127 if Ekind (Ent) = E_Variable
3129 Nkind (Declaration_Node (Ent)) = N_Object_Declaration
3131 No (Expression (Declaration_Node (Ent)))
3134 ("invalid address clause for initialized object &!",
3137 -- If entity is constant, it may be the result of expanding
3138 -- a check. We must verify that its declaration appears
3139 -- before the object in question, else we also reject the
3142 elsif Ekind (Ent) = E_Constant
3143 and then In_Same_Source_Unit (Ent, U_Ent)
3144 and then Sloc (Ent) > Loc_U_Ent
3147 ("invalid address clause for initialized object &!",
3154 -- Otherwise look at the identifier and see if it is OK
3156 if Ekind (Ent) = E_Named_Integer
3158 Ekind (Ent) = E_Named_Real
3165 Ekind (Ent) = E_Constant
3167 Ekind (Ent) = E_In_Parameter
3169 -- This is the case where we must have Ent defined before
3170 -- U_Ent. Clearly if they are in different units this
3171 -- requirement is met since the unit containing Ent is
3172 -- already processed.
3174 if not In_Same_Source_Unit (Ent, U_Ent) then
3177 -- Otherwise location of Ent must be before the location
3178 -- of U_Ent, that's what prior defined means.
3180 elsif Sloc (Ent) < Loc_U_Ent then
3185 ("invalid address clause for initialized object &!",
3187 Error_Msg_Node_2 := U_Ent;
3189 ("\& must be defined before & (RM 13.1(22))!",
3193 elsif Nkind (Original_Node (Nod)) = N_Function_Call then
3194 Check_Expr_Constants (Original_Node (Nod));
3198 ("invalid address clause for initialized object &!",
3201 if Comes_From_Source (Ent) then
3203 ("\reference to variable& not allowed"
3204 & " (RM 13.1(22))!", Nod, Ent);
3207 ("non-static expression not allowed"
3208 & " (RM 13.1(22))!", Nod);
3212 when N_Integer_Literal =>
3214 -- If this is a rewritten unchecked conversion, in a system
3215 -- where Address is an integer type, always use the base type
3216 -- for a literal value. This is user-friendly and prevents
3217 -- order-of-elaboration issues with instances of unchecked
3220 if Nkind (Original_Node (Nod)) = N_Function_Call then
3221 Set_Etype (Nod, Base_Type (Etype (Nod)));
3224 when N_Real_Literal |
3226 N_Character_Literal =>
3230 Check_Expr_Constants (Low_Bound (Nod));
3231 Check_Expr_Constants (High_Bound (Nod));
3233 when N_Explicit_Dereference =>
3234 Check_Expr_Constants (Prefix (Nod));
3236 when N_Indexed_Component =>
3237 Check_Expr_Constants (Prefix (Nod));
3238 Check_List_Constants (Expressions (Nod));
3241 Check_Expr_Constants (Prefix (Nod));
3242 Check_Expr_Constants (Discrete_Range (Nod));
3244 when N_Selected_Component =>
3245 Check_Expr_Constants (Prefix (Nod));
3247 when N_Attribute_Reference =>
3248 if Attribute_Name (Nod) = Name_Address
3250 Attribute_Name (Nod) = Name_Access
3252 Attribute_Name (Nod) = Name_Unchecked_Access
3254 Attribute_Name (Nod) = Name_Unrestricted_Access
3256 Check_At_Constant_Address (Prefix (Nod));
3259 Check_Expr_Constants (Prefix (Nod));
3260 Check_List_Constants (Expressions (Nod));
3264 Check_List_Constants (Component_Associations (Nod));
3265 Check_List_Constants (Expressions (Nod));
3267 when N_Component_Association =>
3268 Check_Expr_Constants (Expression (Nod));
3270 when N_Extension_Aggregate =>
3271 Check_Expr_Constants (Ancestor_Part (Nod));
3272 Check_List_Constants (Component_Associations (Nod));
3273 Check_List_Constants (Expressions (Nod));
3278 when N_Binary_Op | N_Short_Circuit | N_Membership_Test =>
3279 Check_Expr_Constants (Left_Opnd (Nod));
3280 Check_Expr_Constants (Right_Opnd (Nod));
3283 Check_Expr_Constants (Right_Opnd (Nod));
3285 when N_Type_Conversion |
3286 N_Qualified_Expression |
3288 Check_Expr_Constants (Expression (Nod));
3290 when N_Unchecked_Type_Conversion =>
3291 Check_Expr_Constants (Expression (Nod));
3293 -- If this is a rewritten unchecked conversion, subtypes in
3294 -- this node are those created within the instance. To avoid
3295 -- order of elaboration issues, replace them with their base
3296 -- types. Note that address clauses can cause order of
3297 -- elaboration problems because they are elaborated by the
3298 -- back-end at the point of definition, and may mention
3299 -- entities declared in between (as long as everything is
3300 -- static). It is user-friendly to allow unchecked conversions
3303 if Nkind (Original_Node (Nod)) = N_Function_Call then
3304 Set_Etype (Expression (Nod),
3305 Base_Type (Etype (Expression (Nod))));
3306 Set_Etype (Nod, Base_Type (Etype (Nod)));
3309 when N_Function_Call =>
3310 if not Is_Pure (Entity (Name (Nod))) then
3312 ("invalid address clause for initialized object &!",
3316 ("\function & is not pure (RM 13.1(22))!",
3317 Nod, Entity (Name (Nod)));
3320 Check_List_Constants (Parameter_Associations (Nod));
3323 when N_Parameter_Association =>
3324 Check_Expr_Constants (Explicit_Actual_Parameter (Nod));
3328 ("invalid address clause for initialized object &!",
3331 ("\must be constant defined before& (RM 13.1(22))!",
3334 end Check_Expr_Constants;
3336 --------------------------
3337 -- Check_List_Constants --
3338 --------------------------
3340 procedure Check_List_Constants (Lst : List_Id) is
3344 if Present (Lst) then
3345 Nod1 := First (Lst);
3346 while Present (Nod1) loop
3347 Check_Expr_Constants (Nod1);
3351 end Check_List_Constants;
3353 -- Start of processing for Check_Constant_Address_Clause
3356 Check_Expr_Constants (Expr);
3357 end Check_Constant_Address_Clause;
3363 procedure Check_Size
3367 Biased : out Boolean)
3369 UT : constant Entity_Id := Underlying_Type (T);
3375 -- Dismiss cases for generic types or types with previous errors
3378 or else UT = Any_Type
3379 or else Is_Generic_Type (UT)
3380 or else Is_Generic_Type (Root_Type (UT))
3384 -- Check case of bit packed array
3386 elsif Is_Array_Type (UT)
3387 and then Known_Static_Component_Size (UT)
3388 and then Is_Bit_Packed_Array (UT)
3396 Asiz := Component_Size (UT);
3397 Indx := First_Index (UT);
3399 Ityp := Etype (Indx);
3401 -- If non-static bound, then we are not in the business of
3402 -- trying to check the length, and indeed an error will be
3403 -- issued elsewhere, since sizes of non-static array types
3404 -- cannot be set implicitly or explicitly.
3406 if not Is_Static_Subtype (Ityp) then
3410 -- Otherwise accumulate next dimension
3412 Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) -
3413 Expr_Value (Type_Low_Bound (Ityp)) +
3417 exit when No (Indx);
3423 Error_Msg_Uint_1 := Asiz;
3425 ("size for& too small, minimum allowed is ^", N, T);
3426 Set_Esize (T, Asiz);
3427 Set_RM_Size (T, Asiz);
3431 -- All other composite types are ignored
3433 elsif Is_Composite_Type (UT) then
3436 -- For fixed-point types, don't check minimum if type is not frozen,
3437 -- since we don't know all the characteristics of the type that can
3438 -- affect the size (e.g. a specified small) till freeze time.
3440 elsif Is_Fixed_Point_Type (UT)
3441 and then not Is_Frozen (UT)
3445 -- Cases for which a minimum check is required
3448 -- Ignore if specified size is correct for the type
3450 if Known_Esize (UT) and then Siz = Esize (UT) then
3454 -- Otherwise get minimum size
3456 M := UI_From_Int (Minimum_Size (UT));
3460 -- Size is less than minimum size, but one possibility remains
3461 -- that we can manage with the new size if we bias the type.
3463 M := UI_From_Int (Minimum_Size (UT, Biased => True));
3466 Error_Msg_Uint_1 := M;
3468 ("size for& too small, minimum allowed is ^", N, T);
3478 -------------------------
3479 -- Get_Alignment_Value --
3480 -------------------------
3482 function Get_Alignment_Value (Expr : Node_Id) return Uint is
3483 Align : constant Uint := Static_Integer (Expr);
3486 if Align = No_Uint then
3489 elsif Align <= 0 then
3490 Error_Msg_N ("alignment value must be positive", Expr);
3494 for J in Int range 0 .. 64 loop
3496 M : constant Uint := Uint_2 ** J;
3499 exit when M = Align;
3503 ("alignment value must be power of 2", Expr);
3511 end Get_Alignment_Value;
3517 procedure Initialize is
3519 Unchecked_Conversions.Init;
3522 -------------------------
3523 -- Is_Operational_Item --
3524 -------------------------
3526 function Is_Operational_Item (N : Node_Id) return Boolean is
3528 if Nkind (N) /= N_Attribute_Definition_Clause then
3532 Id : constant Attribute_Id := Get_Attribute_Id (Chars (N));
3534 return Id = Attribute_Input
3535 or else Id = Attribute_Output
3536 or else Id = Attribute_Read
3537 or else Id = Attribute_Write
3538 or else Id = Attribute_External_Tag;
3541 end Is_Operational_Item;
3547 function Minimum_Size
3549 Biased : Boolean := False) return Nat
3551 Lo : Uint := No_Uint;
3552 Hi : Uint := No_Uint;
3553 LoR : Ureal := No_Ureal;
3554 HiR : Ureal := No_Ureal;
3555 LoSet : Boolean := False;
3556 HiSet : Boolean := False;
3560 R_Typ : constant Entity_Id := Root_Type (T);
3563 -- If bad type, return 0
3565 if T = Any_Type then
3568 -- For generic types, just return zero. There cannot be any legitimate
3569 -- need to know such a size, but this routine may be called with a
3570 -- generic type as part of normal processing.
3572 elsif Is_Generic_Type (R_Typ)
3573 or else R_Typ = Any_Type
3577 -- Access types. Normally an access type cannot have a size smaller
3578 -- than the size of System.Address. The exception is on VMS, where
3579 -- we have short and long addresses, and it is possible for an access
3580 -- type to have a short address size (and thus be less than the size
3581 -- of System.Address itself). We simply skip the check for VMS, and
3582 -- leave it to the back end to do the check.
3584 elsif Is_Access_Type (T) then
3585 if OpenVMS_On_Target then
3588 return System_Address_Size;
3591 -- Floating-point types
3593 elsif Is_Floating_Point_Type (T) then
3594 return UI_To_Int (Esize (R_Typ));
3598 elsif Is_Discrete_Type (T) then
3600 -- The following loop is looking for the nearest compile time known
3601 -- bounds following the ancestor subtype chain. The idea is to find
3602 -- the most restrictive known bounds information.
3606 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
3611 if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then
3612 Lo := Expr_Rep_Value (Type_Low_Bound (Ancest));
3619 if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then
3620 Hi := Expr_Rep_Value (Type_High_Bound (Ancest));
3626 Ancest := Ancestor_Subtype (Ancest);
3629 Ancest := Base_Type (T);
3631 if Is_Generic_Type (Ancest) then
3637 -- Fixed-point types. We can't simply use Expr_Value to get the
3638 -- Corresponding_Integer_Value values of the bounds, since these do not
3639 -- get set till the type is frozen, and this routine can be called
3640 -- before the type is frozen. Similarly the test for bounds being static
3641 -- needs to include the case where we have unanalyzed real literals for
3644 elsif Is_Fixed_Point_Type (T) then
3646 -- The following loop is looking for the nearest compile time known
3647 -- bounds following the ancestor subtype chain. The idea is to find
3648 -- the most restrictive known bounds information.
3652 if Ancest = Any_Type or else Etype (Ancest) = Any_Type then
3656 -- Note: In the following two tests for LoSet and HiSet, it may
3657 -- seem redundant to test for N_Real_Literal here since normally
3658 -- one would assume that the test for the value being known at
3659 -- compile time includes this case. However, there is a glitch.
3660 -- If the real literal comes from folding a non-static expression,
3661 -- then we don't consider any non- static expression to be known
3662 -- at compile time if we are in configurable run time mode (needed
3663 -- in some cases to give a clearer definition of what is and what
3664 -- is not accepted). So the test is indeed needed. Without it, we
3665 -- would set neither Lo_Set nor Hi_Set and get an infinite loop.
3668 if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal
3669 or else Compile_Time_Known_Value (Type_Low_Bound (Ancest))
3671 LoR := Expr_Value_R (Type_Low_Bound (Ancest));
3678 if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal
3679 or else Compile_Time_Known_Value (Type_High_Bound (Ancest))
3681 HiR := Expr_Value_R (Type_High_Bound (Ancest));
3687 Ancest := Ancestor_Subtype (Ancest);
3690 Ancest := Base_Type (T);
3692 if Is_Generic_Type (Ancest) then
3698 Lo := UR_To_Uint (LoR / Small_Value (T));
3699 Hi := UR_To_Uint (HiR / Small_Value (T));
3701 -- No other types allowed
3704 raise Program_Error;
3707 -- Fall through with Hi and Lo set. Deal with biased case
3710 and then not Is_Fixed_Point_Type (T)
3711 and then not (Is_Enumeration_Type (T)
3712 and then Has_Non_Standard_Rep (T)))
3713 or else Has_Biased_Representation (T)
3719 -- Signed case. Note that we consider types like range 1 .. -1 to be
3720 -- signed for the purpose of computing the size, since the bounds have
3721 -- to be accommodated in the base type.
3723 if Lo < 0 or else Hi < 0 then
3727 -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1))
3728 -- Note that we accommodate the case where the bounds cross. This
3729 -- can happen either because of the way the bounds are declared
3730 -- or because of the algorithm in Freeze_Fixed_Point_Type.
3744 -- If both bounds are positive, make sure that both are represen-
3745 -- table in the case where the bounds are crossed. This can happen
3746 -- either because of the way the bounds are declared, or because of
3747 -- the algorithm in Freeze_Fixed_Point_Type.
3753 -- S = size, (can accommodate 0 .. (2**size - 1))
3756 while Hi >= Uint_2 ** S loop
3764 ---------------------------
3765 -- New_Stream_Subprogram --
3766 ---------------------------
3768 procedure New_Stream_Subprogram
3772 Nam : TSS_Name_Type)
3774 Loc : constant Source_Ptr := Sloc (N);
3775 Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam);
3776 Subp_Id : Entity_Id;
3777 Subp_Decl : Node_Id;
3781 Defer_Declaration : constant Boolean :=
3782 Is_Tagged_Type (Ent) or else Is_Private_Type (Ent);
3783 -- For a tagged type, there is a declaration for each stream attribute
3784 -- at the freeze point, and we must generate only a completion of this
3785 -- declaration. We do the same for private types, because the full view
3786 -- might be tagged. Otherwise we generate a declaration at the point of
3787 -- the attribute definition clause.
3789 function Build_Spec return Node_Id;
3790 -- Used for declaration and renaming declaration, so that this is
3791 -- treated as a renaming_as_body.
3797 function Build_Spec return Node_Id is
3798 Out_P : constant Boolean := (Nam = TSS_Stream_Read);
3801 T_Ref : constant Node_Id := New_Reference_To (Etyp, Loc);
3804 Subp_Id := Make_Defining_Identifier (Loc, Sname);
3806 -- S : access Root_Stream_Type'Class
3808 Formals := New_List (
3809 Make_Parameter_Specification (Loc,
3810 Defining_Identifier =>
3811 Make_Defining_Identifier (Loc, Name_S),
3813 Make_Access_Definition (Loc,
3816 Designated_Type (Etype (F)), Loc))));
3818 if Nam = TSS_Stream_Input then
3819 Spec := Make_Function_Specification (Loc,
3820 Defining_Unit_Name => Subp_Id,
3821 Parameter_Specifications => Formals,
3822 Result_Definition => T_Ref);
3827 Make_Parameter_Specification (Loc,
3828 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
3829 Out_Present => Out_P,
3830 Parameter_Type => T_Ref));
3832 Spec := Make_Procedure_Specification (Loc,
3833 Defining_Unit_Name => Subp_Id,
3834 Parameter_Specifications => Formals);
3840 -- Start of processing for New_Stream_Subprogram
3843 F := First_Formal (Subp);
3845 if Ekind (Subp) = E_Procedure then
3846 Etyp := Etype (Next_Formal (F));
3848 Etyp := Etype (Subp);
3851 -- Prepare subprogram declaration and insert it as an action on the
3852 -- clause node. The visibility for this entity is used to test for
3853 -- visibility of the attribute definition clause (in the sense of
3854 -- 8.3(23) as amended by AI-195).
3856 if not Defer_Declaration then
3858 Make_Subprogram_Declaration (Loc,
3859 Specification => Build_Spec);
3861 -- For a tagged type, there is always a visible declaration for each
3862 -- stream TSS (it is a predefined primitive operation), and the
3863 -- completion of this declaration occurs at the freeze point, which is
3864 -- not always visible at places where the attribute definition clause is
3865 -- visible. So, we create a dummy entity here for the purpose of
3866 -- tracking the visibility of the attribute definition clause itself.
3870 Make_Defining_Identifier (Loc,
3871 Chars => New_External_Name (Sname, 'V'));
3873 Make_Object_Declaration (Loc,
3874 Defining_Identifier => Subp_Id,
3875 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc));
3878 Insert_Action (N, Subp_Decl);
3879 Set_Entity (N, Subp_Id);
3882 Make_Subprogram_Renaming_Declaration (Loc,
3883 Specification => Build_Spec,
3884 Name => New_Reference_To (Subp, Loc));
3886 if Defer_Declaration then
3887 Set_TSS (Base_Type (Ent), Subp_Id);
3889 Insert_Action (N, Subp_Decl);
3890 Copy_TSS (Subp_Id, Base_Type (Ent));
3892 end New_Stream_Subprogram;
3894 ------------------------
3895 -- Rep_Item_Too_Early --
3896 ------------------------
3898 function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is
3900 -- Cannot apply non-operational rep items to generic types
3902 if Is_Operational_Item (N) then
3906 and then Is_Generic_Type (Root_Type (T))
3909 ("representation item not allowed for generic type", N);
3913 -- Otherwise check for incomplete type
3915 if Is_Incomplete_Or_Private_Type (T)
3916 and then No (Underlying_Type (T))
3919 ("representation item must be after full type declaration", N);
3922 -- If the type has incomplete components, a representation clause is
3923 -- illegal but stream attributes and Convention pragmas are correct.
3925 elsif Has_Private_Component (T) then
3926 if Nkind (N) = N_Pragma then
3930 ("representation item must appear after type is fully defined",
3937 end Rep_Item_Too_Early;
3939 -----------------------
3940 -- Rep_Item_Too_Late --
3941 -----------------------
3943 function Rep_Item_Too_Late
3946 FOnly : Boolean := False) return Boolean
3949 Parent_Type : Entity_Id;
3952 -- Output the too late message. Note that this is not considered a
3953 -- serious error, since the effect is simply that we ignore the
3954 -- representation clause in this case.
3960 procedure Too_Late is
3962 Error_Msg_N ("|representation item appears too late!", N);
3965 -- Start of processing for Rep_Item_Too_Late
3968 -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported
3969 -- types, which may be frozen if they appear in a representation clause
3970 -- for a local type.
3973 and then not From_With_Type (T)
3976 S := First_Subtype (T);
3978 if Present (Freeze_Node (S)) then
3980 ("?no more representation items for }", Freeze_Node (S), S);
3985 -- Check for case of non-tagged derived type whose parent either has
3986 -- primitive operations, or is a by reference type (RM 13.1(10)).
3990 and then Is_Derived_Type (T)
3991 and then not Is_Tagged_Type (T)
3993 Parent_Type := Etype (Base_Type (T));
3995 if Has_Primitive_Operations (Parent_Type) then
3998 ("primitive operations already defined for&!", N, Parent_Type);
4001 elsif Is_By_Reference_Type (Parent_Type) then
4004 ("parent type & is a by reference type!", N, Parent_Type);
4009 -- No error, link item into head of chain of rep items for the entity,
4010 -- but avoid chaining if we have an overloadable entity, and the pragma
4011 -- is one that can apply to multiple overloaded entities.
4013 if Is_Overloadable (T)
4014 and then Nkind (N) = N_Pragma
4017 Pname : constant Name_Id := Pragma_Name (N);
4019 if Pname = Name_Convention or else
4020 Pname = Name_Import or else
4021 Pname = Name_Export or else
4022 Pname = Name_External or else
4023 Pname = Name_Interface
4030 Record_Rep_Item (T, N);
4032 end Rep_Item_Too_Late;
4034 -------------------------
4035 -- Same_Representation --
4036 -------------------------
4038 function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is
4039 T1 : constant Entity_Id := Underlying_Type (Typ1);
4040 T2 : constant Entity_Id := Underlying_Type (Typ2);
4043 -- A quick check, if base types are the same, then we definitely have
4044 -- the same representation, because the subtype specific representation
4045 -- attributes (Size and Alignment) do not affect representation from
4046 -- the point of view of this test.
4048 if Base_Type (T1) = Base_Type (T2) then
4051 elsif Is_Private_Type (Base_Type (T2))
4052 and then Base_Type (T1) = Full_View (Base_Type (T2))
4057 -- Tagged types never have differing representations
4059 if Is_Tagged_Type (T1) then
4063 -- Representations are definitely different if conventions differ
4065 if Convention (T1) /= Convention (T2) then
4069 -- Representations are different if component alignments differ
4071 if (Is_Record_Type (T1) or else Is_Array_Type (T1))
4073 (Is_Record_Type (T2) or else Is_Array_Type (T2))
4074 and then Component_Alignment (T1) /= Component_Alignment (T2)
4079 -- For arrays, the only real issue is component size. If we know the
4080 -- component size for both arrays, and it is the same, then that's
4081 -- good enough to know we don't have a change of representation.
4083 if Is_Array_Type (T1) then
4084 if Known_Component_Size (T1)
4085 and then Known_Component_Size (T2)
4086 and then Component_Size (T1) = Component_Size (T2)
4092 -- Types definitely have same representation if neither has non-standard
4093 -- representation since default representations are always consistent.
4094 -- If only one has non-standard representation, and the other does not,
4095 -- then we consider that they do not have the same representation. They
4096 -- might, but there is no way of telling early enough.
4098 if Has_Non_Standard_Rep (T1) then
4099 if not Has_Non_Standard_Rep (T2) then
4103 return not Has_Non_Standard_Rep (T2);
4106 -- Here the two types both have non-standard representation, and we need
4107 -- to determine if they have the same non-standard representation.
4109 -- For arrays, we simply need to test if the component sizes are the
4110 -- same. Pragma Pack is reflected in modified component sizes, so this
4111 -- check also deals with pragma Pack.
4113 if Is_Array_Type (T1) then
4114 return Component_Size (T1) = Component_Size (T2);
4116 -- Tagged types always have the same representation, because it is not
4117 -- possible to specify different representations for common fields.
4119 elsif Is_Tagged_Type (T1) then
4122 -- Case of record types
4124 elsif Is_Record_Type (T1) then
4126 -- Packed status must conform
4128 if Is_Packed (T1) /= Is_Packed (T2) then
4131 -- Otherwise we must check components. Typ2 maybe a constrained
4132 -- subtype with fewer components, so we compare the components
4133 -- of the base types.
4136 Record_Case : declare
4137 CD1, CD2 : Entity_Id;
4139 function Same_Rep return Boolean;
4140 -- CD1 and CD2 are either components or discriminants. This
4141 -- function tests whether the two have the same representation
4147 function Same_Rep return Boolean is
4149 if No (Component_Clause (CD1)) then
4150 return No (Component_Clause (CD2));
4154 Present (Component_Clause (CD2))
4156 Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2)
4158 Esize (CD1) = Esize (CD2);
4162 -- Start of processing for Record_Case
4165 if Has_Discriminants (T1) then
4166 CD1 := First_Discriminant (T1);
4167 CD2 := First_Discriminant (T2);
4169 -- The number of discriminants may be different if the
4170 -- derived type has fewer (constrained by values). The
4171 -- invisible discriminants retain the representation of
4172 -- the original, so the discrepancy does not per se
4173 -- indicate a different representation.
4176 and then Present (CD2)
4178 if not Same_Rep then
4181 Next_Discriminant (CD1);
4182 Next_Discriminant (CD2);
4187 CD1 := First_Component (Underlying_Type (Base_Type (T1)));
4188 CD2 := First_Component (Underlying_Type (Base_Type (T2)));
4190 while Present (CD1) loop
4191 if not Same_Rep then
4194 Next_Component (CD1);
4195 Next_Component (CD2);
4203 -- For enumeration types, we must check each literal to see if the
4204 -- representation is the same. Note that we do not permit enumeration
4205 -- representation clauses for Character and Wide_Character, so these
4206 -- cases were already dealt with.
4208 elsif Is_Enumeration_Type (T1) then
4210 Enumeration_Case : declare
4214 L1 := First_Literal (T1);
4215 L2 := First_Literal (T2);
4217 while Present (L1) loop
4218 if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then
4228 end Enumeration_Case;
4230 -- Any other types have the same representation for these purposes
4235 end Same_Representation;
4237 --------------------
4238 -- Set_Enum_Esize --
4239 --------------------
4241 procedure Set_Enum_Esize (T : Entity_Id) is
4249 -- Find the minimum standard size (8,16,32,64) that fits
4251 Lo := Enumeration_Rep (Entity (Type_Low_Bound (T)));
4252 Hi := Enumeration_Rep (Entity (Type_High_Bound (T)));
4255 if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then
4256 Sz := Standard_Character_Size; -- May be > 8 on some targets
4258 elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then
4261 elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then
4264 else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63);
4269 if Hi < Uint_2**08 then
4270 Sz := Standard_Character_Size; -- May be > 8 on some targets
4272 elsif Hi < Uint_2**16 then
4275 elsif Hi < Uint_2**32 then
4278 else pragma Assert (Hi < Uint_2**63);
4283 -- That minimum is the proper size unless we have a foreign convention
4284 -- and the size required is 32 or less, in which case we bump the size
4285 -- up to 32. This is required for C and C++ and seems reasonable for
4286 -- all other foreign conventions.
4288 if Has_Foreign_Convention (T)
4289 and then Esize (T) < Standard_Integer_Size
4291 Init_Esize (T, Standard_Integer_Size);
4297 ------------------------------
4298 -- Validate_Address_Clauses --
4299 ------------------------------
4301 procedure Validate_Address_Clauses is
4303 for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop
4305 ACCR : Address_Clause_Check_Record
4306 renames Address_Clause_Checks.Table (J);
4317 -- Skip processing of this entry if warning already posted
4319 if not Address_Warning_Posted (ACCR.N) then
4321 Expr := Original_Node (Expression (ACCR.N));
4325 X_Alignment := Alignment (ACCR.X);
4326 Y_Alignment := Alignment (ACCR.Y);
4328 -- Similarly obtain sizes
4330 X_Size := Esize (ACCR.X);
4331 Y_Size := Esize (ACCR.Y);
4333 -- Check for large object overlaying smaller one
4336 and then X_Size > Uint_0
4337 and then X_Size > Y_Size
4340 ("?& overlays smaller object", ACCR.N, ACCR.X);
4342 ("\?program execution may be erroneous", ACCR.N);
4343 Error_Msg_Uint_1 := X_Size;
4345 ("\?size of & is ^", ACCR.N, ACCR.X);
4346 Error_Msg_Uint_1 := Y_Size;
4348 ("\?size of & is ^", ACCR.N, ACCR.Y);
4350 -- Check for inadequate alignment, both of the base object
4351 -- and of the offset, if any.
4353 -- Note: we do not check the alignment if we gave a size
4354 -- warning, since it would likely be redundant.
4356 elsif Y_Alignment /= Uint_0
4357 and then (Y_Alignment < X_Alignment
4360 Nkind (Expr) = N_Attribute_Reference
4362 Attribute_Name (Expr) = Name_Address
4364 Has_Compatible_Alignment
4365 (ACCR.X, Prefix (Expr))
4366 /= Known_Compatible))
4369 ("?specified address for& may be inconsistent "
4373 ("\?program execution may be erroneous (RM 13.3(27))",
4375 Error_Msg_Uint_1 := X_Alignment;
4377 ("\?alignment of & is ^",
4379 Error_Msg_Uint_1 := Y_Alignment;
4381 ("\?alignment of & is ^",
4383 if Y_Alignment >= X_Alignment then
4385 ("\?but offset is not multiple of alignment",
4392 end Validate_Address_Clauses;
4394 -----------------------------------
4395 -- Validate_Unchecked_Conversion --
4396 -----------------------------------
4398 procedure Validate_Unchecked_Conversion
4400 Act_Unit : Entity_Id)
4407 -- Obtain source and target types. Note that we call Ancestor_Subtype
4408 -- here because the processing for generic instantiation always makes
4409 -- subtypes, and we want the original frozen actual types.
4411 -- If we are dealing with private types, then do the check on their
4412 -- fully declared counterparts if the full declarations have been
4413 -- encountered (they don't have to be visible, but they must exist!)
4415 Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit)));
4417 if Is_Private_Type (Source)
4418 and then Present (Underlying_Type (Source))
4420 Source := Underlying_Type (Source);
4423 Target := Ancestor_Subtype (Etype (Act_Unit));
4425 -- If either type is generic, the instantiation happens within a generic
4426 -- unit, and there is nothing to check. The proper check
4427 -- will happen when the enclosing generic is instantiated.
4429 if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then
4433 if Is_Private_Type (Target)
4434 and then Present (Underlying_Type (Target))
4436 Target := Underlying_Type (Target);
4439 -- Source may be unconstrained array, but not target
4441 if Is_Array_Type (Target)
4442 and then not Is_Constrained (Target)
4445 ("unchecked conversion to unconstrained array not allowed", N);
4449 -- Warn if conversion between two different convention pointers
4451 if Is_Access_Type (Target)
4452 and then Is_Access_Type (Source)
4453 and then Convention (Target) /= Convention (Source)
4454 and then Warn_On_Unchecked_Conversion
4456 -- Give warnings for subprogram pointers only on most targets. The
4457 -- exception is VMS, where data pointers can have different lengths
4458 -- depending on the pointer convention.
4460 if Is_Access_Subprogram_Type (Target)
4461 or else Is_Access_Subprogram_Type (Source)
4462 or else OpenVMS_On_Target
4465 ("?conversion between pointers with different conventions!", N);
4469 -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a
4470 -- warning when compiling GNAT-related sources.
4472 if Warn_On_Unchecked_Conversion
4473 and then not In_Predefined_Unit (N)
4474 and then RTU_Loaded (Ada_Calendar)
4476 (Chars (Source) = Name_Time
4478 Chars (Target) = Name_Time)
4480 -- If Ada.Calendar is loaded and the name of one of the operands is
4481 -- Time, there is a good chance that this is Ada.Calendar.Time.
4484 Calendar_Time : constant Entity_Id :=
4485 Full_View (RTE (RO_CA_Time));
4487 pragma Assert (Present (Calendar_Time));
4489 if Source = Calendar_Time
4490 or else Target = Calendar_Time
4493 ("?representation of 'Time values may change between " &
4494 "'G'N'A'T versions", N);
4499 -- Make entry in unchecked conversion table for later processing by
4500 -- Validate_Unchecked_Conversions, which will check sizes and alignments
4501 -- (using values set by the back-end where possible). This is only done
4502 -- if the appropriate warning is active.
4504 if Warn_On_Unchecked_Conversion then
4505 Unchecked_Conversions.Append
4506 (New_Val => UC_Entry'
4511 -- If both sizes are known statically now, then back end annotation
4512 -- is not required to do a proper check but if either size is not
4513 -- known statically, then we need the annotation.
4515 if Known_Static_RM_Size (Source)
4516 and then Known_Static_RM_Size (Target)
4520 Back_Annotate_Rep_Info := True;
4524 -- If unchecked conversion to access type, and access type is declared
4525 -- in the same unit as the unchecked conversion, then set the
4526 -- No_Strict_Aliasing flag (no strict aliasing is implicit in this
4529 if Is_Access_Type (Target) and then
4530 In_Same_Source_Unit (Target, N)
4532 Set_No_Strict_Aliasing (Implementation_Base_Type (Target));
4535 -- Generate N_Validate_Unchecked_Conversion node for back end in
4536 -- case the back end needs to perform special validation checks.
4538 -- Shouldn't this be in Exp_Ch13, since the check only gets done
4539 -- if we have full expansion and the back end is called ???
4542 Make_Validate_Unchecked_Conversion (Sloc (N));
4543 Set_Source_Type (Vnode, Source);
4544 Set_Target_Type (Vnode, Target);
4546 -- If the unchecked conversion node is in a list, just insert before it.
4547 -- If not we have some strange case, not worth bothering about.
4549 if Is_List_Member (N) then
4550 Insert_After (N, Vnode);
4552 end Validate_Unchecked_Conversion;
4554 ------------------------------------
4555 -- Validate_Unchecked_Conversions --
4556 ------------------------------------
4558 procedure Validate_Unchecked_Conversions is
4560 for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop
4562 T : UC_Entry renames Unchecked_Conversions.Table (N);
4564 Eloc : constant Source_Ptr := T.Eloc;
4565 Source : constant Entity_Id := T.Source;
4566 Target : constant Entity_Id := T.Target;
4572 -- This validation check, which warns if we have unequal sizes for
4573 -- unchecked conversion, and thus potentially implementation
4574 -- dependent semantics, is one of the few occasions on which we
4575 -- use the official RM size instead of Esize. See description in
4576 -- Einfo "Handling of Type'Size Values" for details.
4578 if Serious_Errors_Detected = 0
4579 and then Known_Static_RM_Size (Source)
4580 and then Known_Static_RM_Size (Target)
4582 -- Don't do the check if warnings off for either type, note the
4583 -- deliberate use of OR here instead of OR ELSE to get the flag
4584 -- Warnings_Off_Used set for both types if appropriate.
4586 and then not (Has_Warnings_Off (Source)
4588 Has_Warnings_Off (Target))
4590 Source_Siz := RM_Size (Source);
4591 Target_Siz := RM_Size (Target);
4593 if Source_Siz /= Target_Siz then
4595 ("?types for unchecked conversion have different sizes!",
4598 if All_Errors_Mode then
4599 Error_Msg_Name_1 := Chars (Source);
4600 Error_Msg_Uint_1 := Source_Siz;
4601 Error_Msg_Name_2 := Chars (Target);
4602 Error_Msg_Uint_2 := Target_Siz;
4603 Error_Msg ("\size of % is ^, size of % is ^?", Eloc);
4605 Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz);
4607 if Is_Discrete_Type (Source)
4608 and then Is_Discrete_Type (Target)
4610 if Source_Siz > Target_Siz then
4612 ("\?^ high order bits of source will be ignored!",
4615 elsif Is_Unsigned_Type (Source) then
4617 ("\?source will be extended with ^ high order " &
4618 "zero bits?!", Eloc);
4622 ("\?source will be extended with ^ high order " &
4627 elsif Source_Siz < Target_Siz then
4628 if Is_Discrete_Type (Target) then
4629 if Bytes_Big_Endian then
4631 ("\?target value will include ^ undefined " &
4636 ("\?target value will include ^ undefined " &
4643 ("\?^ trailing bits of target value will be " &
4644 "undefined!", Eloc);
4647 else pragma Assert (Source_Siz > Target_Siz);
4649 ("\?^ trailing bits of source will be ignored!",
4656 -- If both types are access types, we need to check the alignment.
4657 -- If the alignment of both is specified, we can do it here.
4659 if Serious_Errors_Detected = 0
4660 and then Ekind (Source) in Access_Kind
4661 and then Ekind (Target) in Access_Kind
4662 and then Target_Strict_Alignment
4663 and then Present (Designated_Type (Source))
4664 and then Present (Designated_Type (Target))
4667 D_Source : constant Entity_Id := Designated_Type (Source);
4668 D_Target : constant Entity_Id := Designated_Type (Target);
4671 if Known_Alignment (D_Source)
4672 and then Known_Alignment (D_Target)
4675 Source_Align : constant Uint := Alignment (D_Source);
4676 Target_Align : constant Uint := Alignment (D_Target);
4679 if Source_Align < Target_Align
4680 and then not Is_Tagged_Type (D_Source)
4682 -- Suppress warning if warnings suppressed on either
4683 -- type or either designated type. Note the use of
4684 -- OR here instead of OR ELSE. That is intentional,
4685 -- we would like to set flag Warnings_Off_Used in
4686 -- all types for which warnings are suppressed.
4688 and then not (Has_Warnings_Off (D_Source)
4690 Has_Warnings_Off (D_Target)
4692 Has_Warnings_Off (Source)
4694 Has_Warnings_Off (Target))
4696 Error_Msg_Uint_1 := Target_Align;
4697 Error_Msg_Uint_2 := Source_Align;
4698 Error_Msg_Node_1 := D_Target;
4699 Error_Msg_Node_2 := D_Source;
4701 ("?alignment of & (^) is stricter than " &
4702 "alignment of & (^)!", Eloc);
4704 ("\?resulting access value may have invalid " &
4705 "alignment!", Eloc);
4713 end Validate_Unchecked_Conversions;