aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.8.3/gcc/ada/restrict.adb
blob: d4acf1dd912bb246e15eb6b566ec9eca35fdbe3a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                             R E S T R I C T                              --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--          Copyright (C) 1992-2012, Free Software Foundation, Inc.         --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
-- for  more details.  You should have  received  a copy of the GNU General --
-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license.          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

with Aspects;  use Aspects;
with Atree;    use Atree;
with Casing;   use Casing;
with Einfo;    use Einfo;
with Errout;   use Errout;
with Debug;    use Debug;
with Fname;    use Fname;
with Fname.UF; use Fname.UF;
with Lib;      use Lib;
with Opt;      use Opt;
with Sinfo;    use Sinfo;
with Sinput;   use Sinput;
with Snames;   use Snames;
with Stand;    use Stand;
with Uname;    use Uname;

package body Restrict is

   Config_Cunit_Boolean_Restrictions : Save_Cunit_Boolean_Restrictions;
   --  Save compilation unit restrictions set by config pragma files

   Restricted_Profile_Result : Boolean := False;
   --  This switch memoizes the result of Restricted_Profile function calls for
   --  improved efficiency. Valid only if Restricted_Profile_Cached is True.
   --  Note: if this switch is ever set True, it is never turned off again.

   Restricted_Profile_Cached : Boolean := False;
   --  This flag is set to True if the Restricted_Profile_Result contains the
   --  correct cached result of Restricted_Profile calls.

   No_Specification_Of_Aspects : array (Aspect_Id) of Source_Ptr :=
                                   (others => No_Location);
   --  Entries in this array are set to point to a previously occuring pragma
   --  that activates a No_Specification_Of_Aspect check.

   No_Specification_Of_Aspect_Warning : array (Aspect_Id) of Boolean :=
                                          (others => True);
   --  An entry in this array is set False in reponse to a previous call to
   --  Set_No_Speficiation_Of_Aspect for pragmas in the main unit that
   --  specify Warning as False. Once set False, an entry is never reset.

   No_Specification_Of_Aspect_Set : Boolean := False;
   --  Set True if any entry of No_Specifcation_Of_Aspects has been set True.
   --  Once set True, this is never turned off again.

   -----------------------
   -- Local Subprograms --
   -----------------------

   procedure Restriction_Msg (R : Restriction_Id; N : Node_Id);
   --  Called if a violation of restriction R at node N is found. This routine
   --  outputs the appropriate message or messages taking care of warning vs
   --  real violation, serious vs non-serious, implicit vs explicit, the second
   --  message giving the profile name if needed, and the location information.

   function Same_Unit (U1, U2 : Node_Id) return Boolean;
   --  Returns True iff U1 and U2 represent the same library unit. Used for
   --  handling of No_Dependence => Unit restriction case.

   function Suppress_Restriction_Message (N : Node_Id) return Boolean;
   --  N is the node for a possible restriction violation message, but the
   --  message is to be suppressed if this is an internal file and this file is
   --  not the main unit. Returns True if message is to be suppressed.

   -------------------
   -- Abort_Allowed --
   -------------------

   function Abort_Allowed return Boolean is
   begin
      if Restrictions.Set (No_Abort_Statements)
        and then Restrictions.Set (Max_Asynchronous_Select_Nesting)
        and then Restrictions.Value (Max_Asynchronous_Select_Nesting) = 0
      then
         return False;
      else
         return True;
      end if;
   end Abort_Allowed;

   ----------------------------------------
   -- Add_To_Config_Boolean_Restrictions --
   ----------------------------------------

   procedure Add_To_Config_Boolean_Restrictions (R : Restriction_Id) is
   begin
      Config_Cunit_Boolean_Restrictions (R) := True;
   end Add_To_Config_Boolean_Restrictions;
   --  Add specified restriction to stored configuration boolean restrictions.
   --  This is used for handling the special case of No_Elaboration_Code.

   -------------------------
   -- Check_Compiler_Unit --
   -------------------------

   procedure Check_Compiler_Unit (N : Node_Id) is
   begin
      if Is_Compiler_Unit (Get_Source_Unit (N)) then
         Error_Msg_N ("use of construct not allowed in compiler", N);
      end if;
   end Check_Compiler_Unit;

   ------------------------------------
   -- Check_Elaboration_Code_Allowed --
   ------------------------------------

   procedure Check_Elaboration_Code_Allowed (N : Node_Id) is
   begin
      Check_Restriction (No_Elaboration_Code, N);
   end Check_Elaboration_Code_Allowed;

   -----------------------------
   -- Check_SPARK_Restriction --
   -----------------------------

   procedure Check_SPARK_Restriction
     (Msg   : String;
      N     : Node_Id;
      Force : Boolean := False)
   is
      Msg_Issued          : Boolean;
      Save_Error_Msg_Sloc : Source_Ptr;
   begin
      if Force or else Comes_From_Source (Original_Node (N)) then

         if Restriction_Check_Required (SPARK)
           and then Is_In_Hidden_Part_In_SPARK (Sloc (N))
         then
            return;
         end if;

         --  Since the call to Restriction_Msg from Check_Restriction may set
         --  Error_Msg_Sloc to the location of the pragma restriction, save and
         --  restore the previous value of the global variable around the call.

         Save_Error_Msg_Sloc := Error_Msg_Sloc;
         Check_Restriction (Msg_Issued, SPARK, First_Node (N));
         Error_Msg_Sloc := Save_Error_Msg_Sloc;

         if Msg_Issued then
            Error_Msg_F ("\\| " & Msg, N);
         end if;
      end if;
   end Check_SPARK_Restriction;

   procedure Check_SPARK_Restriction (Msg1, Msg2 : String; N : Node_Id) is
      Msg_Issued          : Boolean;
      Save_Error_Msg_Sloc : Source_Ptr;
   begin
      pragma Assert (Msg2'Length /= 0 and then Msg2 (Msg2'First) = '\');

      if Comes_From_Source (Original_Node (N)) then

         if Restriction_Check_Required (SPARK)
           and then Is_In_Hidden_Part_In_SPARK (Sloc (N))
         then
            return;
         end if;

         --  Since the call to Restriction_Msg from Check_Restriction may set
         --  Error_Msg_Sloc to the location of the pragma restriction, save and
         --  restore the previous value of the global variable around the call.

         Save_Error_Msg_Sloc := Error_Msg_Sloc;
         Check_Restriction (Msg_Issued, SPARK, First_Node (N));
         Error_Msg_Sloc := Save_Error_Msg_Sloc;

         if Msg_Issued then
            Error_Msg_F ("\\| " & Msg1, N);
            Error_Msg_F (Msg2, N);
         end if;
      end if;
   end Check_SPARK_Restriction;

   --------------------------------
   -- Check_No_Implicit_Aliasing --
   --------------------------------

   procedure Check_No_Implicit_Aliasing (Obj : Node_Id) is
      E : Entity_Id;

   begin
      --  If restriction not active, nothing to check

      if not Restriction_Active (No_Implicit_Aliasing) then
         return;
      end if;

      --  If we have an entity name, check entity

      if Is_Entity_Name (Obj) then
         E := Entity (Obj);

         --  Restriction applies to entities that are objects

         if Is_Object (E) then
            if Is_Aliased (E) then
               return;

            elsif Present (Renamed_Object (E)) then
               Check_No_Implicit_Aliasing (Renamed_Object (E));
               return;
            end if;

         --  If we don't have an object, then it's OK

         else
            return;
         end if;

      --  For selected component, check selector

      elsif Nkind (Obj) = N_Selected_Component then
         Check_No_Implicit_Aliasing (Selector_Name (Obj));
         return;

      --  Indexed component is OK if aliased components

      elsif Nkind (Obj) = N_Indexed_Component then
         if Has_Aliased_Components (Etype (Prefix (Obj)))
           or else
             (Is_Access_Type (Etype (Prefix (Obj)))
               and then Has_Aliased_Components
                          (Designated_Type (Etype (Prefix (Obj)))))
         then
            return;
         end if;

      --  For type conversion, check converted expression

      elsif Nkind_In (Obj, N_Unchecked_Type_Conversion, N_Type_Conversion) then
         Check_No_Implicit_Aliasing (Expression (Obj));
         return;

      --  Explicit dereference is always OK

      elsif Nkind (Obj) = N_Explicit_Dereference then
         return;
      end if;

      --  If we fall through, then we have an aliased view that does not meet
      --  the rules for being explicitly aliased, so issue restriction msg.

      Check_Restriction (No_Implicit_Aliasing, Obj);
   end Check_No_Implicit_Aliasing;

   -----------------------------------------
   -- Check_Implicit_Dynamic_Code_Allowed --
   -----------------------------------------

   procedure Check_Implicit_Dynamic_Code_Allowed (N : Node_Id) is
   begin
      Check_Restriction (No_Implicit_Dynamic_Code, N);
   end Check_Implicit_Dynamic_Code_Allowed;

   ----------------------------------
   -- Check_No_Implicit_Heap_Alloc --
   ----------------------------------

   procedure Check_No_Implicit_Heap_Alloc (N : Node_Id) is
   begin
      Check_Restriction (No_Implicit_Heap_Allocations, N);
   end Check_No_Implicit_Heap_Alloc;

   -----------------------------------
   -- Check_Obsolescent_2005_Entity --
   -----------------------------------

   procedure Check_Obsolescent_2005_Entity (E : Entity_Id; N : Node_Id) is
      function Chars_Is (E : Entity_Id; S : String) return Boolean;
      --  Return True iff Chars (E) matches S (given in lower case)

      function Chars_Is (E : Entity_Id; S : String) return Boolean is
         Nam : constant Name_Id := Chars (E);
      begin
         if Length_Of_Name (Nam) /= S'Length then
            return False;
         else
            return Get_Name_String (Nam) = S;
         end if;
      end Chars_Is;

   --  Start of processing for Check_Obsolescent_2005_Entity

   begin
      if Restriction_Check_Required (No_Obsolescent_Features)
        and then Ada_Version >= Ada_2005
        and then Chars_Is (Scope (E),                 "handling")
        and then Chars_Is (Scope (Scope (E)),         "characters")
        and then Chars_Is (Scope (Scope (Scope (E))), "ada")
        and then Scope (Scope (Scope (Scope (E)))) = Standard_Standard
      then
         if Chars_Is (E, "is_character")      or else
            Chars_Is (E, "is_string")         or else
            Chars_Is (E, "to_character")      or else
            Chars_Is (E, "to_string")         or else
            Chars_Is (E, "to_wide_character") or else
            Chars_Is (E, "to_wide_string")
         then
            Check_Restriction (No_Obsolescent_Features, N);
         end if;
      end if;
   end Check_Obsolescent_2005_Entity;

   ---------------------------
   -- Check_Restricted_Unit --
   ---------------------------

   procedure Check_Restricted_Unit (U : Unit_Name_Type; N : Node_Id) is
   begin
      if Suppress_Restriction_Message (N) then
         return;

      elsif Is_Spec_Name (U) then
         declare
            Fnam : constant File_Name_Type :=
                     Get_File_Name (U, Subunit => False);

         begin
            --  Get file name

            Get_Name_String (Fnam);

            --  Nothing to do if name not at least 5 characters long ending
            --  in .ads or .adb extension, which we strip.

            if Name_Len < 5
              or else (Name_Buffer (Name_Len - 3 .. Name_Len) /= ".ads"
                         and then
                       Name_Buffer (Name_Len - 3 .. Name_Len) /= ".adb")
            then
               return;
            end if;

            --  Strip extension and pad to eight characters

            Name_Len := Name_Len - 4;
            Add_Str_To_Name_Buffer ((Name_Len + 1 .. 8 => ' '));

            --  If predefined unit, check the list of restricted units

            if Is_Predefined_File_Name (Fnam) then
               for J in Unit_Array'Range loop
                  if Name_Len = 8
                    and then Name_Buffer (1 .. 8) = Unit_Array (J).Filenm
                  then
                     Check_Restriction (Unit_Array (J).Res_Id, N);
                  end if;
               end loop;

               --  If not predefined unit, then one special check still
               --  remains. GNAT.Current_Exception is not allowed if we have
               --  restriction No_Exception_Propagation active.

            else
               if Name_Buffer (1 .. 8) = "g-curexc" then
                  Check_Restriction (No_Exception_Propagation, N);
               end if;
            end if;
         end;
      end if;
   end Check_Restricted_Unit;

   -----------------------
   -- Check_Restriction --
   -----------------------

   procedure Check_Restriction
     (R : Restriction_Id;
      N : Node_Id;
      V : Uint := Uint_Minus_1)
   is
      Msg_Issued : Boolean;
      pragma Unreferenced (Msg_Issued);
   begin
      Check_Restriction (Msg_Issued, R, N, V);
   end Check_Restriction;

   procedure Check_Restriction
     (Msg_Issued : out Boolean;
      R          : Restriction_Id;
      N          : Node_Id;
      V          : Uint := Uint_Minus_1)
   is
      VV : Integer;
      --  V converted to integer form. If V is greater than Integer'Last,
      --  it is reset to minus 1 (unknown value).

      procedure Update_Restrictions (Info : in out Restrictions_Info);
      --  Update violation information in Info.Violated and Info.Count

      -------------------------
      -- Update_Restrictions --
      -------------------------

      procedure Update_Restrictions (Info : in out Restrictions_Info) is
      begin
         --  If not violated, set as violated now

         if not Info.Violated (R) then
            Info.Violated (R) := True;

            if R in All_Parameter_Restrictions then
               if VV < 0 then
                  Info.Unknown (R) := True;
                  Info.Count (R) := 1;
               else
                  Info.Count (R) := VV;
               end if;
            end if;

         --  Otherwise if violated already and a parameter restriction,
         --  update count by maximizing or summing depending on restriction.

         elsif R in All_Parameter_Restrictions then

            --  If new value is unknown, result is unknown

            if VV < 0 then
               Info.Unknown (R) := True;

            --  If checked by maximization, do maximization

            elsif R in Checked_Max_Parameter_Restrictions then
               Info.Count (R) := Integer'Max (Info.Count (R), VV);

            --  If checked by adding, do add, checking for overflow

            elsif R in Checked_Add_Parameter_Restrictions then
               declare
                  pragma Unsuppress (Overflow_Check);
               begin
                  Info.Count (R) := Info.Count (R) + VV;
               exception
                  when Constraint_Error =>
                     Info.Count (R) := Integer'Last;
                     Info.Unknown (R) := True;
               end;

            --  Should not be able to come here, known counts should only
            --  occur for restrictions that are Checked_max or Checked_Sum.

            else
               raise Program_Error;
            end if;
         end if;
      end Update_Restrictions;

   --  Start of processing for Check_Restriction

   begin
      Msg_Issued := False;

      --  In CodePeer and Alfa mode, we do not want to check for any
      --  restriction, or set additional restrictions other than those already
      --  set in gnat1drv.adb so that we have consistency between each
      --  compilation.

      if CodePeer_Mode or Alfa_Mode then
         return;
      end if;

      --  In SPARK mode, issue an error for any use of class-wide, even if the
      --  No_Dispatch restriction is not set.

      if R = No_Dispatch then
         Check_SPARK_Restriction ("class-wide is not allowed", N);
      end if;

      if UI_Is_In_Int_Range (V) then
         VV := Integer (UI_To_Int (V));
      else
         VV := -1;
      end if;

      --  Count can only be specified in the checked val parameter case

      pragma Assert (VV < 0 or else R in Checked_Val_Parameter_Restrictions);

      --  Nothing to do if value of zero specified for parameter restriction

      if VV = 0 then
         return;
      end if;

      --  Update current restrictions

      Update_Restrictions (Restrictions);

      --  If in main extended unit, update main restrictions as well. Note
      --  that as usual we check for Main_Unit explicitly to deal with the
      --  case of configuration pragma files.

      if Current_Sem_Unit = Main_Unit
        or else In_Extended_Main_Source_Unit (N)
      then
         Update_Restrictions (Main_Restrictions);
      end if;

      --  Nothing to do if restriction message suppressed

      if Suppress_Restriction_Message (N) then
         null;

      --  If restriction not set, nothing to do

      elsif not Restrictions.Set (R) then
         null;

      --  Don't complain about No_Obsolescent_Features in an instance, since we
      --  will complain on the template, which is much better. Are there other
      --  cases like this ??? Do we need a more general mechanism ???

      elsif R = No_Obsolescent_Features
        and then Instantiation_Location (Sloc (N)) /= No_Location
      then
         null;

      --  Here if restriction set, check for violation (this is a Boolean
      --  restriction, or a parameter restriction with a value of zero and an
      --  unknown count, or a parameter restriction with a known value that
      --  exceeds the restriction count).

      elsif R in All_Boolean_Restrictions
        or else (Restrictions.Unknown (R)
                   and then Restrictions.Value (R) = 0)
        or else Restrictions.Count (R) > Restrictions.Value (R)
      then
         Msg_Issued := True;
         Restriction_Msg (R, N);
      end if;
   end Check_Restriction;

   -------------------------------------
   -- Check_Restriction_No_Dependence --
   -------------------------------------

   procedure Check_Restriction_No_Dependence (U : Node_Id; Err : Node_Id) is
      DU : Node_Id;

   begin
      --  Ignore call if node U is not in the main source unit. This avoids
      --  cascaded errors, e.g. when Ada.Containers units with other units.

      if not In_Extended_Main_Source_Unit (U) then
         return;
      end if;

      --  Loop through entries in No_Dependence table to check each one in turn

      for J in No_Dependences.First .. No_Dependences.Last loop
         DU := No_Dependences.Table (J).Unit;

         if Same_Unit (U, DU) then
            Error_Msg_Sloc := Sloc (DU);
            Error_Msg_Node_1 := DU;

            if No_Dependences.Table (J).Warn then
               Error_Msg
                 ("??violation of restriction `No_Dependence '='> &`#",
                  Sloc (Err));
            else
               Error_Msg
                 ("|violation of restriction `No_Dependence '='> &`#",
                  Sloc (Err));
            end if;

            return;
         end if;
      end loop;
   end Check_Restriction_No_Dependence;

   --------------------------------------------------
   -- Check_Restriction_No_Specification_Of_Aspect --
   --------------------------------------------------

   procedure Check_Restriction_No_Specification_Of_Aspect (N : Node_Id) is
      A_Id : Aspect_Id;
      Id   : Node_Id;

   begin
      --  Ignore call if no instances of this restriction set

      if not No_Specification_Of_Aspect_Set then
         return;
      end if;

      --  Ignore call if node N is not in the main source unit, since we only
      --  give messages for the main unit. This avoids giving messages for
      --  aspects that are specified in withed units.

      if not In_Extended_Main_Source_Unit (N) then
         return;
      end if;

      Id := Identifier (N);
      A_Id := Get_Aspect_Id (Chars (Id));
      pragma Assert (A_Id /= No_Aspect);

      Error_Msg_Sloc := No_Specification_Of_Aspects (A_Id);

      if Error_Msg_Sloc /= No_Location then
         Error_Msg_Node_1 := Id;
         Error_Msg_Warn := No_Specification_Of_Aspect_Warning (A_Id);
         Error_Msg_N
           ("<violation of restriction `No_Specification_Of_Aspect '='> &`#",
            Id);
      end if;
   end Check_Restriction_No_Specification_Of_Aspect;

   --------------------------------------
   -- Check_Wide_Character_Restriction --
   --------------------------------------

   procedure Check_Wide_Character_Restriction (E : Entity_Id; N : Node_Id) is
   begin
      if Restriction_Check_Required (No_Wide_Characters)
        and then Comes_From_Source (N)
      then
         declare
            T : constant Entity_Id := Root_Type (E);
         begin
            if T = Standard_Wide_Character      or else
               T = Standard_Wide_String         or else
               T = Standard_Wide_Wide_Character or else
               T = Standard_Wide_Wide_String
            then
               Check_Restriction (No_Wide_Characters, N);
            end if;
         end;
      end if;
   end Check_Wide_Character_Restriction;

   ----------------------------------------
   -- Cunit_Boolean_Restrictions_Restore --
   ----------------------------------------

   procedure Cunit_Boolean_Restrictions_Restore
     (R : Save_Cunit_Boolean_Restrictions)
   is
   begin
      for J in Cunit_Boolean_Restrictions loop
         Restrictions.Set (J) := R (J);
      end loop;

      --  If No_Elaboration_Code set in configuration restrictions, and we
      --  in the main extended source, then set it here now. This is part of
      --  the special processing for No_Elaboration_Code.

      if In_Extended_Main_Source_Unit (Cunit_Entity (Current_Sem_Unit))
        and then Config_Cunit_Boolean_Restrictions (No_Elaboration_Code)
      then
         Restrictions.Set (No_Elaboration_Code) := True;
      end if;
   end Cunit_Boolean_Restrictions_Restore;

   -------------------------------------
   -- Cunit_Boolean_Restrictions_Save --
   -------------------------------------

   function Cunit_Boolean_Restrictions_Save
     return Save_Cunit_Boolean_Restrictions
   is
      R : Save_Cunit_Boolean_Restrictions;

   begin
      for J in Cunit_Boolean_Restrictions loop
         R (J) := Restrictions.Set (J);
      end loop;

      return R;
   end Cunit_Boolean_Restrictions_Save;

   ------------------------
   -- Get_Restriction_Id --
   ------------------------

   function Get_Restriction_Id
     (N : Name_Id) return Restriction_Id
   is
   begin
      Get_Name_String (N);
      Set_Casing (All_Upper_Case);

      for J in All_Restrictions loop
         declare
            S : constant String := Restriction_Id'Image (J);
         begin
            if S = Name_Buffer (1 .. Name_Len) then
               return J;
            end if;
         end;
      end loop;

      return Not_A_Restriction_Id;
   end Get_Restriction_Id;

   --------------------------------
   -- Is_In_Hidden_Part_In_SPARK --
   --------------------------------

   function Is_In_Hidden_Part_In_SPARK (Loc : Source_Ptr) return Boolean is
   begin
      --  Loop through table of hidden ranges

      for J in SPARK_Hides.First .. SPARK_Hides.Last loop
         if SPARK_Hides.Table (J).Start <= Loc
           and then Loc < SPARK_Hides.Table (J).Stop
         then
            return True;
         end if;
      end loop;

      return False;
   end Is_In_Hidden_Part_In_SPARK;

   -------------------------------
   -- No_Exception_Handlers_Set --
   -------------------------------

   function No_Exception_Handlers_Set return Boolean is
   begin
      return (No_Run_Time_Mode or else Configurable_Run_Time_Mode)
        and then (Restrictions.Set (No_Exception_Handlers)
                    or else
                  Restrictions.Set (No_Exception_Propagation));
   end No_Exception_Handlers_Set;

   -------------------------------------
   -- No_Exception_Propagation_Active --
   -------------------------------------

   function No_Exception_Propagation_Active return Boolean is
   begin
      return (No_Run_Time_Mode
               or else Configurable_Run_Time_Mode
               or else Debug_Flag_Dot_G)
        and then Restriction_Active (No_Exception_Propagation);
   end No_Exception_Propagation_Active;

   ----------------------------------
   -- Process_Restriction_Synonyms --
   ----------------------------------

   --  Note: body of this function must be coordinated with list of
   --  renaming declarations in System.Rident.

   function Process_Restriction_Synonyms (N : Node_Id) return Name_Id
   is
      Old_Name : constant Name_Id := Chars (N);
      New_Name : Name_Id;

   begin
      case Old_Name is
         when Name_Boolean_Entry_Barriers =>
            New_Name := Name_Simple_Barriers;

         when Name_Max_Entry_Queue_Depth =>
            New_Name := Name_Max_Entry_Queue_Length;

         when Name_No_Dynamic_Interrupts =>
            New_Name := Name_No_Dynamic_Attachment;

         when Name_No_Requeue =>
            New_Name := Name_No_Requeue_Statements;

         when Name_No_Task_Attributes =>
            New_Name := Name_No_Task_Attributes_Package;

         when others =>
            return Old_Name;
      end case;

      if Warn_On_Obsolescent_Feature then
         Error_Msg_Name_1 := Old_Name;
         Error_Msg_N ("restriction identifier % is obsolescent?j?", N);
         Error_Msg_Name_1 := New_Name;
         Error_Msg_N ("|use restriction identifier % instead?j?", N);
      end if;

      return New_Name;
   end Process_Restriction_Synonyms;

   --------------------------------------
   -- Reset_Cunit_Boolean_Restrictions --
   --------------------------------------

   procedure Reset_Cunit_Boolean_Restrictions is
   begin
      for J in Cunit_Boolean_Restrictions loop
         Restrictions.Set (J) := False;
      end loop;
   end Reset_Cunit_Boolean_Restrictions;

   -----------------------------------------------
   -- Restore_Config_Cunit_Boolean_Restrictions --
   -----------------------------------------------

   procedure Restore_Config_Cunit_Boolean_Restrictions is
   begin
      Cunit_Boolean_Restrictions_Restore (Config_Cunit_Boolean_Restrictions);
   end Restore_Config_Cunit_Boolean_Restrictions;

   ------------------------
   -- Restricted_Profile --
   ------------------------

   function Restricted_Profile return Boolean is
   begin
      if Restricted_Profile_Cached then
         return Restricted_Profile_Result;

      else
         Restricted_Profile_Result := True;
         Restricted_Profile_Cached := True;

         declare
            R : Restriction_Flags  renames Profile_Info (Restricted).Set;
            V : Restriction_Values renames Profile_Info (Restricted).Value;
         begin
            for J in R'Range loop
               if R (J)
                 and then (Restrictions.Set (J) = False
                             or else Restriction_Warnings (J)
                             or else
                               (J in All_Parameter_Restrictions
                                  and then Restrictions.Value (J) > V (J)))
               then
                  Restricted_Profile_Result := False;
                  exit;
               end if;
            end loop;

            return Restricted_Profile_Result;
         end;
      end if;
   end Restricted_Profile;

   ------------------------
   -- Restriction_Active --
   ------------------------

   function Restriction_Active (R : All_Restrictions) return Boolean is
   begin
      return Restrictions.Set (R) and then not Restriction_Warnings (R);
   end Restriction_Active;

   --------------------------------
   -- Restriction_Check_Required --
   --------------------------------

   function Restriction_Check_Required (R : All_Restrictions) return Boolean is
   begin
      return Restrictions.Set (R);
   end Restriction_Check_Required;

   ---------------------
   -- Restriction_Msg --
   ---------------------

   procedure Restriction_Msg (R : Restriction_Id; N : Node_Id) is
      Msg : String (1 .. 100);
      Len : Natural := 0;

      procedure Add_Char (C : Character);
      --  Append given character to Msg, bumping Len

      procedure Add_Str (S : String);
      --  Append given string to Msg, bumping Len appropriately

      procedure Id_Case (S : String; Quotes : Boolean := True);
      --  Given a string S, case it according to current identifier casing,
      --  except for SPARK (an acronym) which is set all upper case, and store
      --  in Error_Msg_String. Then append `~` to the message buffer to output
      --  the string unchanged surrounded in quotes. The quotes are suppressed
      --  if Quotes = False.

      --------------
      -- Add_Char --
      --------------

      procedure Add_Char (C : Character) is
      begin
         Len := Len + 1;
         Msg (Len) := C;
      end Add_Char;

      -------------
      -- Add_Str --
      -------------

      procedure Add_Str (S : String) is
      begin
         Msg (Len + 1 .. Len + S'Length) := S;
         Len := Len + S'Length;
      end Add_Str;

      -------------
      -- Id_Case --
      -------------

      procedure Id_Case (S : String; Quotes : Boolean := True) is
      begin
         Name_Buffer (1 .. S'Last) := S;
         Name_Len := S'Length;

         if R = SPARK then
            Set_All_Upper_Case;
         else
            Set_Casing (Identifier_Casing (Get_Source_File_Index (Sloc (N))));
         end if;

         Error_Msg_Strlen := Name_Len;
         Error_Msg_String (1 .. Name_Len) := Name_Buffer (1 .. Name_Len);

         if Quotes then
            Add_Str ("`~`");
         else
            Add_Char ('~');
         end if;
      end Id_Case;

   --  Start of processing for Restriction_Msg

   begin
      --  Set warning message if warning

      if Restriction_Warnings (R) then
         Add_Str ("??");

      --  If real violation (not warning), then mark it as non-serious unless
      --  it is a violation of No_Finalization in which case we leave it as a
      --  serious message, since otherwise we get crashes during attempts to
      --  expand stuff that is not properly formed due to assumptions made
      --  about no finalization being present.

      elsif R /= No_Finalization then
         Add_Char ('|');
      end if;

      Error_Msg_Sloc := Restrictions_Loc (R);

      --  Set main message, adding implicit if no source location

      if Error_Msg_Sloc > No_Location
        or else Error_Msg_Sloc = System_Location
      then
         Add_Str ("violation of restriction ");
      else
         Add_Str ("violation of implicit restriction ");
         Error_Msg_Sloc := No_Location;
      end if;

      --  Case of parameterized restriction

      if R in All_Parameter_Restrictions then
         Add_Char ('`');
         Id_Case (Restriction_Id'Image (R), Quotes => False);
         Add_Str (" = ^`");
         Error_Msg_Uint_1 := UI_From_Int (Int (Restrictions.Value (R)));

      --  Case of boolean restriction

      else
         Id_Case (Restriction_Id'Image (R));
      end if;

      --  Case of no secondary profile continuation message

      if Restriction_Profile_Name (R) = No_Profile then
         if Error_Msg_Sloc /= No_Location then
            Add_Char ('#');
         end if;

         Add_Char ('!');
         Error_Msg_N (Msg (1 .. Len), N);

      --  Case of secondary profile continuation message present

      else
         Add_Char ('!');
         Error_Msg_N (Msg (1 .. Len), N);

         Len := 0;
         Add_Char ('\');

         --  Set as warning if warning case

         if Restriction_Warnings (R) then
            Add_Str ("??");
         end if;

         --  Set main message

         Add_Str ("from profile ");
         Id_Case (Profile_Name'Image (Restriction_Profile_Name (R)));

         --  Add location if we have one

         if Error_Msg_Sloc /= No_Location then
            Add_Char ('#');
         end if;

         --  Output unconditional message and we are done

         Add_Char ('!');
         Error_Msg_N (Msg (1 .. Len), N);
      end if;
   end Restriction_Msg;

   ---------------
   -- Same_Unit --
   ---------------

   function Same_Unit (U1, U2 : Node_Id) return Boolean is
   begin
      if Nkind (U1) = N_Identifier then
         return Nkind (U2) = N_Identifier and then Chars (U1) = Chars (U2);

      elsif Nkind (U2) = N_Identifier then
         return False;

      elsif (Nkind (U1) = N_Selected_Component
             or else Nkind (U1) = N_Expanded_Name)
        and then
          (Nkind (U2) = N_Selected_Component
           or else Nkind (U2) = N_Expanded_Name)
      then
         return Same_Unit (Prefix (U1), Prefix (U2))
           and then Same_Unit (Selector_Name (U1), Selector_Name (U2));
      else
         return False;
      end if;
   end Same_Unit;

   --------------------------------------------
   -- Save_Config_Cunit_Boolean_Restrictions --
   --------------------------------------------

   procedure Save_Config_Cunit_Boolean_Restrictions is
   begin
      Config_Cunit_Boolean_Restrictions := Cunit_Boolean_Restrictions_Save;
   end Save_Config_Cunit_Boolean_Restrictions;

   ------------------------------
   -- Set_Hidden_Part_In_SPARK --
   ------------------------------

   procedure Set_Hidden_Part_In_SPARK (Loc1, Loc2 : Source_Ptr) is
   begin
      SPARK_Hides.Increment_Last;
      SPARK_Hides.Table (SPARK_Hides.Last).Start := Loc1;
      SPARK_Hides.Table (SPARK_Hides.Last).Stop  := Loc2;
   end Set_Hidden_Part_In_SPARK;

   ------------------------------
   -- Set_Profile_Restrictions --
   ------------------------------

   procedure Set_Profile_Restrictions
     (P    : Profile_Name;
      N    : Node_Id;
      Warn : Boolean)
   is
      R : Restriction_Flags  renames Profile_Info (P).Set;
      V : Restriction_Values renames Profile_Info (P).Value;

   begin
      for J in R'Range loop
         if R (J) then
            declare
               Already_Restricted : constant Boolean := Restriction_Active (J);

            begin
               --  Set the restriction

               if J in All_Boolean_Restrictions then
                  Set_Restriction (J, N);
               else
                  Set_Restriction (J, N, V (J));
               end if;

               --  Record that this came from a Profile[_Warnings] restriction

               Restriction_Profile_Name (J) := P;

               --  Set warning flag, except that we do not set the warning
               --  flag if the restriction was already active and this is
               --  the warning case. That avoids a warning overriding a real
               --  restriction, which should never happen.

               if not (Warn and Already_Restricted) then
                  Restriction_Warnings (J) := Warn;
               end if;
            end;
         end if;
      end loop;
   end Set_Profile_Restrictions;

   ---------------------
   -- Set_Restriction --
   ---------------------

   --  Case of Boolean restriction

   procedure Set_Restriction
     (R : All_Boolean_Restrictions;
      N : Node_Id)
   is
   begin
      Restrictions.Set (R) := True;

      if Restricted_Profile_Cached and Restricted_Profile_Result then
         null;
      else
         Restricted_Profile_Cached := False;
      end if;

      --  Set location, but preserve location of system restriction for nice
      --  error msg with run time name.

      if Restrictions_Loc (R) /= System_Location then
         Restrictions_Loc (R) := Sloc (N);
      end if;

      --  Note restriction came from restriction pragma, not profile

      Restriction_Profile_Name (R) := No_Profile;

      --  Record the restriction if we are in the main unit, or in the extended
      --  main unit. The reason that we test separately for Main_Unit is that
      --  gnat.adc is processed with Current_Sem_Unit = Main_Unit, but nodes in
      --  gnat.adc do not appear to be in the extended main source unit (they
      --  probably should do ???)

      if Current_Sem_Unit = Main_Unit
        or else In_Extended_Main_Source_Unit (N)
      then
         if not Restriction_Warnings (R) then
            Main_Restrictions.Set (R) := True;
         end if;
      end if;
   end Set_Restriction;

   --  Case of parameter restriction

   procedure Set_Restriction
     (R : All_Parameter_Restrictions;
      N : Node_Id;
      V : Integer)
   is
   begin
      if Restricted_Profile_Cached and Restricted_Profile_Result then
         null;
      else
         Restricted_Profile_Cached := False;
      end if;

      if Restrictions.Set (R) then
         if V < Restrictions.Value (R) then
            Restrictions.Value (R) := V;
            Restrictions_Loc (R) := Sloc (N);
         end if;

      else
         Restrictions.Set (R) := True;
         Restrictions.Value (R) := V;
         Restrictions_Loc (R) := Sloc (N);
      end if;

      --  Record the restriction if we are in the main unit, or in the extended
      --  main unit. The reason that we test separately for Main_Unit is that
      --  gnat.adc is processed with Current_Sem_Unit = Main_Unit, but nodes in
      --  gnat.adc do not appear to be the extended main source unit (they
      --  probably should do ???)

      if Current_Sem_Unit = Main_Unit
        or else In_Extended_Main_Source_Unit (N)
      then
         if Main_Restrictions.Set (R) then
            if V < Main_Restrictions.Value (R) then
               Main_Restrictions.Value (R) := V;
            end if;

         elsif not Restriction_Warnings (R) then
            Main_Restrictions.Set (R) := True;
            Main_Restrictions.Value (R) := V;
         end if;
      end if;

      --  Note restriction came from restriction pragma, not profile

      Restriction_Profile_Name (R) := No_Profile;
   end Set_Restriction;

   -----------------------------------
   -- Set_Restriction_No_Dependence --
   -----------------------------------

   procedure Set_Restriction_No_Dependence
     (Unit    : Node_Id;
      Warn    : Boolean;
      Profile : Profile_Name := No_Profile)
   is
   begin
      --  Loop to check for duplicate entry

      for J in No_Dependences.First .. No_Dependences.Last loop

         --  Case of entry already in table

         if Same_Unit (Unit, No_Dependences.Table (J).Unit) then

            --  Error has precedence over warning

            if not Warn then
               No_Dependences.Table (J).Warn := False;
            end if;

            return;
         end if;
      end loop;

      --  Entry is not currently in table

      No_Dependences.Append ((Unit, Warn, Profile));
   end Set_Restriction_No_Dependence;

   ------------------------------------------------
   -- Set_Restriction_No_Specification_Of_Aspect --
   ------------------------------------------------

   procedure Set_Restriction_No_Specification_Of_Aspect
     (N       : Node_Id;
      Warning : Boolean)
   is
      A_Id : constant Aspect_Id_Exclude_No_Aspect := Get_Aspect_Id (Chars (N));

   begin
      No_Specification_Of_Aspects (A_Id) := Sloc (N);

      if Warning = False then
         No_Specification_Of_Aspect_Warning (A_Id) := False;
      end if;

      No_Specification_Of_Aspect_Set := True;
   end Set_Restriction_No_Specification_Of_Aspect;

   ----------------------------------
   -- Suppress_Restriction_Message --
   ----------------------------------

   function Suppress_Restriction_Message (N : Node_Id) return Boolean is
   begin
      --  We only output messages for the extended main source unit

      if In_Extended_Main_Source_Unit (N) then
         return False;

      --  If loaded by rtsfind, then suppress message

      elsif Sloc (N) <= No_Location then
         return True;

      --  Otherwise suppress message if internal file

      else
         return Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (N)));
      end if;
   end Suppress_Restriction_Message;

   ---------------------
   -- Tasking_Allowed --
   ---------------------

   function Tasking_Allowed return Boolean is
   begin
      return not Restrictions.Set (No_Tasking)
        and then (not Restrictions.Set (Max_Tasks)
                    or else Restrictions.Value (Max_Tasks) > 0);
   end Tasking_Allowed;

end Restrict;