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
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
|
/* Perform an inferior function call, for GDB, the GNU debugger.
Copyright (C) 1986-2017 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT 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
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "infcall.h"
#include "breakpoint.h"
#include "tracepoint.h"
#include "target.h"
#include "regcache.h"
#include "inferior.h"
#include "infrun.h"
#include "block.h"
#include "gdbcore.h"
#include "language.h"
#include "objfiles.h"
#include "gdbcmd.h"
#include "command.h"
#include "dummy-frame.h"
#include "ada-lang.h"
#include "gdbthread.h"
#include "event-top.h"
#include "observer.h"
#include "top.h"
#include "interps.h"
#include "thread-fsm.h"
/* If we can't find a function's name from its address,
we print this instead. */
#define RAW_FUNCTION_ADDRESS_FORMAT "at 0x%s"
#define RAW_FUNCTION_ADDRESS_SIZE (sizeof (RAW_FUNCTION_ADDRESS_FORMAT) \
+ 2 * sizeof (CORE_ADDR))
/* NOTE: cagney/2003-04-16: What's the future of this code?
GDB needs an asynchronous expression evaluator, that means an
asynchronous inferior function call implementation, and that in
turn means restructuring the code so that it is event driven. */
/* How you should pass arguments to a function depends on whether it
was defined in K&R style or prototype style. If you define a
function using the K&R syntax that takes a `float' argument, then
callers must pass that argument as a `double'. If you define the
function using the prototype syntax, then you must pass the
argument as a `float', with no promotion.
Unfortunately, on certain older platforms, the debug info doesn't
indicate reliably how each function was defined. A function type's
TYPE_PROTOTYPED flag may be clear, even if the function was defined
in prototype style. When calling a function whose TYPE_PROTOTYPED
flag is clear, GDB consults this flag to decide what to do.
For modern targets, it is proper to assume that, if the prototype
flag is clear, that can be trusted: `float' arguments should be
promoted to `double'. For some older targets, if the prototype
flag is clear, that doesn't tell us anything. The default is to
trust the debug information; the user can override this behavior
with "set coerce-float-to-double 0". */
static int coerce_float_to_double_p = 1;
static void
show_coerce_float_to_double_p (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file,
_("Coercion of floats to doubles "
"when calling functions is %s.\n"),
value);
}
/* This boolean tells what gdb should do if a signal is received while
in a function called from gdb (call dummy). If set, gdb unwinds
the stack and restore the context to what as it was before the
call.
The default is to stop in the frame where the signal was received. */
static int unwind_on_signal_p = 0;
static void
show_unwind_on_signal_p (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file,
_("Unwinding of stack if a signal is "
"received while in a call dummy is %s.\n"),
value);
}
/* This boolean tells what gdb should do if a std::terminate call is
made while in a function called from gdb (call dummy).
As the confines of a single dummy stack prohibit out-of-frame
handlers from handling a raised exception, and as out-of-frame
handlers are common in C++, this can lead to no handler being found
by the unwinder, and a std::terminate call. This is a false positive.
If set, gdb unwinds the stack and restores the context to what it
was before the call.
The default is to unwind the frame if a std::terminate call is
made. */
static int unwind_on_terminating_exception_p = 1;
static void
show_unwind_on_terminating_exception_p (struct ui_file *file, int from_tty,
struct cmd_list_element *c,
const char *value)
{
fprintf_filtered (file,
_("Unwind stack if a C++ exception is "
"unhandled while in a call dummy is %s.\n"),
value);
}
/* Perform the standard coercions that are specified
for arguments to be passed to C or Ada functions.
If PARAM_TYPE is non-NULL, it is the expected parameter type.
IS_PROTOTYPED is non-zero if the function declaration is prototyped.
SP is the stack pointer were additional data can be pushed (updating
its value as needed). */
static struct value *
value_arg_coerce (struct gdbarch *gdbarch, struct value *arg,
struct type *param_type, int is_prototyped, CORE_ADDR *sp)
{
const struct builtin_type *builtin = builtin_type (gdbarch);
struct type *arg_type = check_typedef (value_type (arg));
struct type *type
= param_type ? check_typedef (param_type) : arg_type;
/* Perform any Ada-specific coercion first. */
if (current_language->la_language == language_ada)
arg = ada_convert_actual (arg, type);
/* Force the value to the target if we will need its address. At
this point, we could allocate arguments on the stack instead of
calling malloc if we knew that their addresses would not be
saved by the called function. */
arg = value_coerce_to_target (arg);
switch (TYPE_CODE (type))
{
case TYPE_CODE_REF:
case TYPE_CODE_RVALUE_REF:
{
struct value *new_value;
if (TYPE_IS_REFERENCE (arg_type))
return value_cast_pointers (type, arg, 0);
/* Cast the value to the reference's target type, and then
convert it back to a reference. This will issue an error
if the value was not previously in memory - in some cases
we should clearly be allowing this, but how? */
new_value = value_cast (TYPE_TARGET_TYPE (type), arg);
new_value = value_ref (new_value, TYPE_CODE (type));
return new_value;
}
case TYPE_CODE_INT:
case TYPE_CODE_CHAR:
case TYPE_CODE_BOOL:
case TYPE_CODE_ENUM:
/* If we don't have a prototype, coerce to integer type if necessary. */
if (!is_prototyped)
{
if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int))
type = builtin->builtin_int;
}
/* Currently all target ABIs require at least the width of an integer
type for an argument. We may have to conditionalize the following
type coercion for future targets. */
if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_int))
type = builtin->builtin_int;
break;
case TYPE_CODE_FLT:
if (!is_prototyped && coerce_float_to_double_p)
{
if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin->builtin_double))
type = builtin->builtin_double;
else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin->builtin_double))
type = builtin->builtin_long_double;
}
break;
case TYPE_CODE_FUNC:
type = lookup_pointer_type (type);
break;
case TYPE_CODE_ARRAY:
/* Arrays are coerced to pointers to their first element, unless
they are vectors, in which case we want to leave them alone,
because they are passed by value. */
if (current_language->c_style_arrays)
if (!TYPE_VECTOR (type))
type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
break;
case TYPE_CODE_UNDEF:
case TYPE_CODE_PTR:
case TYPE_CODE_STRUCT:
case TYPE_CODE_UNION:
case TYPE_CODE_VOID:
case TYPE_CODE_SET:
case TYPE_CODE_RANGE:
case TYPE_CODE_STRING:
case TYPE_CODE_ERROR:
case TYPE_CODE_MEMBERPTR:
case TYPE_CODE_METHODPTR:
case TYPE_CODE_METHOD:
case TYPE_CODE_COMPLEX:
default:
break;
}
return value_cast (type, arg);
}
/* Return the return type of a function with its first instruction exactly at
the PC address. Return NULL otherwise. */
static struct type *
find_function_return_type (CORE_ADDR pc)
{
struct symbol *sym = find_pc_function (pc);
if (sym != NULL && BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) == pc
&& SYMBOL_TYPE (sym) != NULL)
return TYPE_TARGET_TYPE (SYMBOL_TYPE (sym));
return NULL;
}
/* Determine a function's address and its return type from its value.
Calls error() if the function is not valid for calling. */
CORE_ADDR
find_function_addr (struct value *function, struct type **retval_type)
{
struct type *ftype = check_typedef (value_type (function));
struct gdbarch *gdbarch = get_type_arch (ftype);
struct type *value_type = NULL;
/* Initialize it just to avoid a GCC false warning. */
CORE_ADDR funaddr = 0;
/* If it's a member function, just look at the function
part of it. */
/* Determine address to call. */
if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
|| TYPE_CODE (ftype) == TYPE_CODE_METHOD)
funaddr = value_address (function);
else if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
{
funaddr = value_as_address (function);
ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
|| TYPE_CODE (ftype) == TYPE_CODE_METHOD)
funaddr = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr,
¤t_target);
}
if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
|| TYPE_CODE (ftype) == TYPE_CODE_METHOD)
{
value_type = TYPE_TARGET_TYPE (ftype);
if (TYPE_GNU_IFUNC (ftype))
{
funaddr = gnu_ifunc_resolve_addr (gdbarch, funaddr);
/* Skip querying the function symbol if no RETVAL_TYPE has been
asked for. */
if (retval_type)
value_type = find_function_return_type (funaddr);
}
}
else if (TYPE_CODE (ftype) == TYPE_CODE_INT)
{
/* Handle the case of functions lacking debugging info.
Their values are characters since their addresses are char. */
if (TYPE_LENGTH (ftype) == 1)
funaddr = value_as_address (value_addr (function));
else
{
/* Handle function descriptors lacking debug info. */
int found_descriptor = 0;
funaddr = 0; /* pacify "gcc -Werror" */
if (VALUE_LVAL (function) == lval_memory)
{
CORE_ADDR nfunaddr;
funaddr = value_as_address (value_addr (function));
nfunaddr = funaddr;
funaddr = gdbarch_convert_from_func_ptr_addr (gdbarch, funaddr,
¤t_target);
if (funaddr != nfunaddr)
found_descriptor = 1;
}
if (!found_descriptor)
/* Handle integer used as address of a function. */
funaddr = (CORE_ADDR) value_as_long (function);
}
}
else
error (_("Invalid data type for function to be called."));
if (retval_type != NULL)
*retval_type = value_type;
return funaddr + gdbarch_deprecated_function_start_offset (gdbarch);
}
/* For CALL_DUMMY_ON_STACK, push a breakpoint sequence that the called
function returns to. */
static CORE_ADDR
push_dummy_code (struct gdbarch *gdbarch,
CORE_ADDR sp, CORE_ADDR funaddr,
struct value **args, int nargs,
struct type *value_type,
CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
struct regcache *regcache)
{
gdb_assert (gdbarch_push_dummy_code_p (gdbarch));
return gdbarch_push_dummy_code (gdbarch, sp, funaddr,
args, nargs, value_type, real_pc, bp_addr,
regcache);
}
/* See infcall.h. */
void
error_call_unknown_return_type (const char *func_name)
{
if (func_name != NULL)
error (_("'%s' has unknown return type; "
"cast the call to its declared return type"),
func_name);
else
error (_("function has unknown return type; "
"cast the call to its declared return type"));
}
/* Fetch the name of the function at FUNADDR.
This is used in printing an error message for call_function_by_hand.
BUF is used to print FUNADDR in hex if the function name cannot be
determined. It must be large enough to hold formatted result of
RAW_FUNCTION_ADDRESS_FORMAT. */
static const char *
get_function_name (CORE_ADDR funaddr, char *buf, int buf_size)
{
{
struct symbol *symbol = find_pc_function (funaddr);
if (symbol)
return SYMBOL_PRINT_NAME (symbol);
}
{
/* Try the minimal symbols. */
struct bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (funaddr);
if (msymbol.minsym)
return MSYMBOL_PRINT_NAME (msymbol.minsym);
}
{
char *tmp = xstrprintf (_(RAW_FUNCTION_ADDRESS_FORMAT),
hex_string (funaddr));
gdb_assert (strlen (tmp) + 1 <= buf_size);
strcpy (buf, tmp);
xfree (tmp);
return buf;
}
}
/* All the meta data necessary to extract the call's return value. */
struct call_return_meta_info
{
/* The caller frame's architecture. */
struct gdbarch *gdbarch;
/* The called function. */
struct value *function;
/* The return value's type. */
struct type *value_type;
/* Are we returning a value using a structure return or a normal
value return? */
int struct_return_p;
/* If using a structure return, this is the structure's address. */
CORE_ADDR struct_addr;
/* Whether stack temporaries are enabled. */
int stack_temporaries_enabled;
};
/* Extract the called function's return value. */
static struct value *
get_call_return_value (struct call_return_meta_info *ri)
{
struct value *retval = NULL;
int stack_temporaries = thread_stack_temporaries_enabled_p (inferior_ptid);
if (TYPE_CODE (ri->value_type) == TYPE_CODE_VOID)
retval = allocate_value (ri->value_type);
else if (ri->struct_return_p)
{
if (stack_temporaries)
{
retval = value_from_contents_and_address (ri->value_type, NULL,
ri->struct_addr);
push_thread_stack_temporary (inferior_ptid, retval);
}
else
{
retval = allocate_value (ri->value_type);
read_value_memory (retval, 0, 1, ri->struct_addr,
value_contents_raw (retval),
TYPE_LENGTH (ri->value_type));
}
}
else
{
retval = allocate_value (ri->value_type);
gdbarch_return_value (ri->gdbarch, ri->function, ri->value_type,
get_current_regcache (),
value_contents_raw (retval), NULL);
if (stack_temporaries && class_or_union_p (ri->value_type))
{
/* Values of class type returned in registers are copied onto
the stack and their lval_type set to lval_memory. This is
required because further evaluation of the expression
could potentially invoke methods on the return value
requiring GDB to evaluate the "this" pointer. To evaluate
the this pointer, GDB needs the memory address of the
value. */
value_force_lval (retval, ri->struct_addr);
push_thread_stack_temporary (inferior_ptid, retval);
}
}
gdb_assert (retval != NULL);
return retval;
}
/* Data for the FSM that manages an infcall. It's main job is to
record the called function's return value. */
struct call_thread_fsm
{
/* The base class. */
struct thread_fsm thread_fsm;
/* All the info necessary to be able to extract the return
value. */
struct call_return_meta_info return_meta_info;
/* The called function's return value. This is extracted from the
target before the dummy frame is popped. */
struct value *return_value;
/* The top level that started the infcall (and is synchronously
waiting for it to end). */
struct ui *waiting_ui;
};
static int call_thread_fsm_should_stop (struct thread_fsm *self,
struct thread_info *thread);
static int call_thread_fsm_should_notify_stop (struct thread_fsm *self);
/* call_thread_fsm's vtable. */
static struct thread_fsm_ops call_thread_fsm_ops =
{
NULL, /*dtor */
NULL, /* clean_up */
call_thread_fsm_should_stop,
NULL, /* return_value */
NULL, /* async_reply_reason*/
call_thread_fsm_should_notify_stop,
};
/* Allocate a new call_thread_fsm object. */
static struct call_thread_fsm *
new_call_thread_fsm (struct ui *waiting_ui, struct interp *cmd_interp,
struct gdbarch *gdbarch, struct value *function,
struct type *value_type,
int struct_return_p, CORE_ADDR struct_addr)
{
struct call_thread_fsm *sm;
sm = XCNEW (struct call_thread_fsm);
thread_fsm_ctor (&sm->thread_fsm, &call_thread_fsm_ops, cmd_interp);
sm->return_meta_info.gdbarch = gdbarch;
sm->return_meta_info.function = function;
sm->return_meta_info.value_type = value_type;
sm->return_meta_info.struct_return_p = struct_return_p;
sm->return_meta_info.struct_addr = struct_addr;
sm->waiting_ui = waiting_ui;
return sm;
}
/* Implementation of should_stop method for infcalls. */
static int
call_thread_fsm_should_stop (struct thread_fsm *self,
struct thread_info *thread)
{
struct call_thread_fsm *f = (struct call_thread_fsm *) self;
if (stop_stack_dummy == STOP_STACK_DUMMY)
{
/* Done. */
thread_fsm_set_finished (self);
/* Stash the return value before the dummy frame is popped and
registers are restored to what they were before the
call.. */
f->return_value = get_call_return_value (&f->return_meta_info);
/* Break out of wait_sync_command_done. */
scoped_restore save_ui = make_scoped_restore (¤t_ui, f->waiting_ui);
target_terminal::ours ();
f->waiting_ui->prompt_state = PROMPT_NEEDED;
}
return 1;
}
/* Implementation of should_notify_stop method for infcalls. */
static int
call_thread_fsm_should_notify_stop (struct thread_fsm *self)
{
if (thread_fsm_finished_p (self))
{
/* Infcall succeeded. Be silent and proceed with evaluating the
expression. */
return 0;
}
/* Something wrong happened. E.g., an unexpected breakpoint
triggered, or a signal was intercepted. Notify the stop. */
return 1;
}
/* Subroutine of call_function_by_hand to simplify it.
Start up the inferior and wait for it to stop.
Return the exception if there's an error, or an exception with
reason >= 0 if there's no error.
This is done inside a TRY_CATCH so the caller needn't worry about
thrown errors. The caller should rethrow if there's an error. */
static struct gdb_exception
run_inferior_call (struct call_thread_fsm *sm,
struct thread_info *call_thread, CORE_ADDR real_pc)
{
struct gdb_exception caught_error = exception_none;
int saved_in_infcall = call_thread->control.in_infcall;
ptid_t call_thread_ptid = call_thread->ptid;
enum prompt_state saved_prompt_state = current_ui->prompt_state;
int was_running = call_thread->state == THREAD_RUNNING;
int saved_ui_async = current_ui->async;
/* Infcalls run synchronously, in the foreground. */
current_ui->prompt_state = PROMPT_BLOCKED;
/* So that we don't print the prompt prematurely in
fetch_inferior_event. */
current_ui->async = 0;
delete_file_handler (current_ui->input_fd);
call_thread->control.in_infcall = 1;
clear_proceed_status (0);
/* Associate the FSM with the thread after clear_proceed_status
(otherwise it'd clear this FSM), and before anything throws, so
we don't leak it (and any resources it manages). */
call_thread->thread_fsm = &sm->thread_fsm;
disable_watchpoints_before_interactive_call_start ();
/* We want to print return value, please... */
call_thread->control.proceed_to_finish = 1;
TRY
{
proceed (real_pc, GDB_SIGNAL_0);
/* Inferior function calls are always synchronous, even if the
target supports asynchronous execution. */
wait_sync_command_done ();
}
CATCH (e, RETURN_MASK_ALL)
{
caught_error = e;
}
END_CATCH
/* If GDB has the prompt blocked before, then ensure that it remains
so. normal_stop calls async_enable_stdin, so reset the prompt
state again here. In other cases, stdin will be re-enabled by
inferior_event_handler, when an exception is thrown. */
current_ui->prompt_state = saved_prompt_state;
if (current_ui->prompt_state == PROMPT_BLOCKED)
delete_file_handler (current_ui->input_fd);
else
ui_register_input_event_handler (current_ui);
current_ui->async = saved_ui_async;
/* At this point the current thread may have changed. Refresh
CALL_THREAD as it could be invalid if its thread has exited. */
call_thread = find_thread_ptid (call_thread_ptid);
/* If the infcall does NOT succeed, normal_stop will have already
finished the thread states. However, on success, normal_stop
defers here, so that we can set back the thread states to what
they were before the call. Note that we must also finish the
state of new threads that might have spawned while the call was
running. The main cases to handle are:
- "(gdb) print foo ()", or any other command that evaluates an
expression at the prompt. (The thread was marked stopped before.)
- "(gdb) break foo if return_false()" or similar cases where we
do an infcall while handling an event (while the thread is still
marked running). In this example, whether the condition
evaluates true and thus we'll present a user-visible stop is
decided elsewhere. */
if (!was_running
&& ptid_equal (call_thread_ptid, inferior_ptid)
&& stop_stack_dummy == STOP_STACK_DUMMY)
finish_thread_state (user_visible_resume_ptid (0));
enable_watchpoints_after_interactive_call_stop ();
/* Call breakpoint_auto_delete on the current contents of the bpstat
of inferior call thread.
If all error()s out of proceed ended up calling normal_stop
(and perhaps they should; it already does in the special case
of error out of resume()), then we wouldn't need this. */
if (caught_error.reason < 0)
{
if (call_thread != NULL)
breakpoint_auto_delete (call_thread->control.stop_bpstat);
}
if (call_thread != NULL)
call_thread->control.in_infcall = saved_in_infcall;
return caught_error;
}
/* A cleanup function that calls delete_std_terminate_breakpoint. */
static void
cleanup_delete_std_terminate_breakpoint (void *ignore)
{
delete_std_terminate_breakpoint ();
}
/* See infcall.h. */
struct value *
call_function_by_hand (struct value *function,
type *default_return_type,
int nargs, struct value **args)
{
return call_function_by_hand_dummy (function, default_return_type,
nargs, args, NULL, NULL);
}
/* All this stuff with a dummy frame may seem unnecessarily complicated
(why not just save registers in GDB?). The purpose of pushing a dummy
frame which looks just like a real frame is so that if you call a
function and then hit a breakpoint (get a signal, etc), "backtrace"
will look right. Whether the backtrace needs to actually show the
stack at the time the inferior function was called is debatable, but
it certainly needs to not display garbage. So if you are contemplating
making dummy frames be different from normal frames, consider that. */
/* Perform a function call in the inferior.
ARGS is a vector of values of arguments (NARGS of them).
FUNCTION is a value, the function to be called.
Returns a value representing what the function returned.
May fail to return, if a breakpoint or signal is hit
during the execution of the function.
ARGS is modified to contain coerced values. */
struct value *
call_function_by_hand_dummy (struct value *function,
type *default_return_type,
int nargs, struct value **args,
dummy_frame_dtor_ftype *dummy_dtor,
void *dummy_dtor_data)
{
CORE_ADDR sp;
struct type *values_type, *target_values_type;
unsigned char struct_return = 0, hidden_first_param_p = 0;
CORE_ADDR struct_addr = 0;
struct infcall_control_state *inf_status;
struct cleanup *inf_status_cleanup;
struct infcall_suspend_state *caller_state;
CORE_ADDR funaddr;
CORE_ADDR real_pc;
struct type *ftype = check_typedef (value_type (function));
CORE_ADDR bp_addr;
struct frame_id dummy_id;
struct cleanup *args_cleanup;
struct frame_info *frame;
struct gdbarch *gdbarch;
struct cleanup *terminate_bp_cleanup;
ptid_t call_thread_ptid;
struct gdb_exception e;
char name_buf[RAW_FUNCTION_ADDRESS_SIZE];
int stack_temporaries = thread_stack_temporaries_enabled_p (inferior_ptid);
if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
if (!target_has_execution)
noprocess ();
if (get_traceframe_number () >= 0)
error (_("May not call functions while looking at trace frames."));
if (execution_direction == EXEC_REVERSE)
error (_("Cannot call functions in reverse mode."));
frame = get_current_frame ();
gdbarch = get_frame_arch (frame);
if (!gdbarch_push_dummy_call_p (gdbarch))
error (_("This target does not support function calls."));
/* A cleanup for the inferior status.
This is only needed while we're preparing the inferior function call. */
inf_status = save_infcall_control_state ();
inf_status_cleanup
= make_cleanup_restore_infcall_control_state (inf_status);
/* Save the caller's registers and other state associated with the
inferior itself so that they can be restored once the
callee returns. To allow nested calls the registers are (further
down) pushed onto a dummy frame stack. Include a cleanup (which
is tossed once the regcache has been pushed). */
caller_state = save_infcall_suspend_state ();
make_cleanup_restore_infcall_suspend_state (caller_state);
/* Ensure that the initial SP is correctly aligned. */
{
CORE_ADDR old_sp = get_frame_sp (frame);
if (gdbarch_frame_align_p (gdbarch))
{
sp = gdbarch_frame_align (gdbarch, old_sp);
/* NOTE: cagney/2003-08-13: Skip the "red zone". For some
ABIs, a function can use memory beyond the inner most stack
address. AMD64 called that region the "red zone". Skip at
least the "red zone" size before allocating any space on
the stack. */
if (gdbarch_inner_than (gdbarch, 1, 2))
sp -= gdbarch_frame_red_zone_size (gdbarch);
else
sp += gdbarch_frame_red_zone_size (gdbarch);
/* Still aligned? */
gdb_assert (sp == gdbarch_frame_align (gdbarch, sp));
/* NOTE: cagney/2002-09-18:
On a RISC architecture, a void parameterless generic dummy
frame (i.e., no parameters, no result) typically does not
need to push anything the stack and hence can leave SP and
FP. Similarly, a frameless (possibly leaf) function does
not push anything on the stack and, hence, that too can
leave FP and SP unchanged. As a consequence, a sequence of
void parameterless generic dummy frame calls to frameless
functions will create a sequence of effectively identical
frames (SP, FP and TOS and PC the same). This, not
suprisingly, results in what appears to be a stack in an
infinite loop --- when GDB tries to find a generic dummy
frame on the internal dummy frame stack, it will always
find the first one.
To avoid this problem, the code below always grows the
stack. That way, two dummy frames can never be identical.
It does burn a few bytes of stack but that is a small price
to pay :-). */
if (sp == old_sp)
{
if (gdbarch_inner_than (gdbarch, 1, 2))
/* Stack grows down. */
sp = gdbarch_frame_align (gdbarch, old_sp - 1);
else
/* Stack grows up. */
sp = gdbarch_frame_align (gdbarch, old_sp + 1);
}
/* SP may have underflown address zero here from OLD_SP. Memory access
functions will probably fail in such case but that is a target's
problem. */
}
else
/* FIXME: cagney/2002-09-18: Hey, you loose!
Who knows how badly aligned the SP is!
If the generic dummy frame ends up empty (because nothing is
pushed) GDB won't be able to correctly perform back traces.
If a target is having trouble with backtraces, first thing to
do is add FRAME_ALIGN() to the architecture vector. If that
fails, try dummy_id().
If the ABI specifies a "Red Zone" (see the doco) the code
below will quietly trash it. */
sp = old_sp;
/* Skip over the stack temporaries that might have been generated during
the evaluation of an expression. */
if (stack_temporaries)
{
struct value *lastval;
lastval = get_last_thread_stack_temporary (inferior_ptid);
if (lastval != NULL)
{
CORE_ADDR lastval_addr = value_address (lastval);
if (gdbarch_inner_than (gdbarch, 1, 2))
{
gdb_assert (sp >= lastval_addr);
sp = lastval_addr;
}
else
{
gdb_assert (sp <= lastval_addr);
sp = lastval_addr + TYPE_LENGTH (value_type (lastval));
}
if (gdbarch_frame_align_p (gdbarch))
sp = gdbarch_frame_align (gdbarch, sp);
}
}
}
funaddr = find_function_addr (function, &values_type);
if (values_type == NULL)
values_type = default_return_type;
if (values_type == NULL)
{
const char *name = get_function_name (funaddr,
name_buf, sizeof (name_buf));
error (_("'%s' has unknown return type; "
"cast the call to its declared return type"),
name);
}
values_type = check_typedef (values_type);
/* Are we returning a value using a structure return (passing a
hidden argument pointing to storage) or a normal value return?
There are two cases: language-mandated structure return and
target ABI structure return. The variable STRUCT_RETURN only
describes the latter. The language version is handled by passing
the return location as the first parameter to the function,
even preceding "this". This is different from the target
ABI version, which is target-specific; for instance, on ia64
the first argument is passed in out0 but the hidden structure
return pointer would normally be passed in r8. */
if (gdbarch_return_in_first_hidden_param_p (gdbarch, values_type))
{
hidden_first_param_p = 1;
/* Tell the target specific argument pushing routine not to
expect a value. */
target_values_type = builtin_type (gdbarch)->builtin_void;
}
else
{
struct_return = using_struct_return (gdbarch, function, values_type);
target_values_type = values_type;
}
observer_notify_inferior_call_pre (inferior_ptid, funaddr);
/* Determine the location of the breakpoint (and possibly other
stuff) that the called function will return to. The SPARC, for a
function returning a structure or union, needs to make space for
not just the breakpoint but also an extra word containing the
size (?) of the structure being passed. */
switch (gdbarch_call_dummy_location (gdbarch))
{
case ON_STACK:
{
const gdb_byte *bp_bytes;
CORE_ADDR bp_addr_as_address;
int bp_size;
/* Be careful BP_ADDR is in inferior PC encoding while
BP_ADDR_AS_ADDRESS is a plain memory address. */
sp = push_dummy_code (gdbarch, sp, funaddr, args, nargs,
target_values_type, &real_pc, &bp_addr,
get_current_regcache ());
/* Write a legitimate instruction at the point where the infcall
breakpoint is going to be inserted. While this instruction
is never going to be executed, a user investigating the
memory from GDB would see this instruction instead of random
uninitialized bytes. We chose the breakpoint instruction
as it may look as the most logical one to the user and also
valgrind 3.7.0 needs it for proper vgdb inferior calls.
If software breakpoints are unsupported for this target we
leave the user visible memory content uninitialized. */
bp_addr_as_address = bp_addr;
bp_bytes = gdbarch_breakpoint_from_pc (gdbarch, &bp_addr_as_address,
&bp_size);
if (bp_bytes != NULL)
write_memory (bp_addr_as_address, bp_bytes, bp_size);
}
break;
case AT_ENTRY_POINT:
{
CORE_ADDR dummy_addr;
real_pc = funaddr;
dummy_addr = entry_point_address ();
/* A call dummy always consists of just a single breakpoint, so
its address is the same as the address of the dummy.
The actual breakpoint is inserted separatly so there is no need to
write that out. */
bp_addr = dummy_addr;
break;
}
default:
internal_error (__FILE__, __LINE__, _("bad switch"));
}
if (nargs < TYPE_NFIELDS (ftype))
error (_("Too few arguments in function call."));
{
int i;
for (i = nargs - 1; i >= 0; i--)
{
int prototyped;
struct type *param_type;
/* FIXME drow/2002-05-31: Should just always mark methods as
prototyped. Can we respect TYPE_VARARGS? Probably not. */
if (TYPE_CODE (ftype) == TYPE_CODE_METHOD)
prototyped = 1;
if (TYPE_TARGET_TYPE (ftype) == NULL && TYPE_NFIELDS (ftype) == 0
&& default_return_type != NULL)
{
/* Calling a no-debug function with the return type
explicitly cast. Assume the function is prototyped,
with a prototype matching the types of the arguments.
E.g., with:
float mult (float v1, float v2) { return v1 * v2; }
This:
(gdb) p (float) mult (2.0f, 3.0f)
Is a simpler alternative to:
(gdb) p ((float (*) (float, float)) mult) (2.0f, 3.0f)
*/
prototyped = 1;
}
else if (i < TYPE_NFIELDS (ftype))
prototyped = TYPE_PROTOTYPED (ftype);
else
prototyped = 0;
if (i < TYPE_NFIELDS (ftype))
param_type = TYPE_FIELD_TYPE (ftype, i);
else
param_type = NULL;
args[i] = value_arg_coerce (gdbarch, args[i],
param_type, prototyped, &sp);
if (param_type != NULL && language_pass_by_reference (param_type))
args[i] = value_addr (args[i]);
}
}
/* Reserve space for the return structure to be written on the
stack, if necessary. Make certain that the value is correctly
aligned.
While evaluating expressions, we reserve space on the stack for
return values of class type even if the language ABI and the target
ABI do not require that the return value be passed as a hidden first
argument. This is because we want to store the return value as an
on-stack temporary while the expression is being evaluated. This
enables us to have chained function calls in expressions.
Keeping the return values as on-stack temporaries while the expression
is being evaluated is OK because the thread is stopped until the
expression is completely evaluated. */
if (struct_return || hidden_first_param_p
|| (stack_temporaries && class_or_union_p (values_type)))
{
if (gdbarch_inner_than (gdbarch, 1, 2))
{
/* Stack grows downward. Align STRUCT_ADDR and SP after
making space for the return value. */
sp -= TYPE_LENGTH (values_type);
if (gdbarch_frame_align_p (gdbarch))
sp = gdbarch_frame_align (gdbarch, sp);
struct_addr = sp;
}
else
{
/* Stack grows upward. Align the frame, allocate space, and
then again, re-align the frame??? */
if (gdbarch_frame_align_p (gdbarch))
sp = gdbarch_frame_align (gdbarch, sp);
struct_addr = sp;
sp += TYPE_LENGTH (values_type);
if (gdbarch_frame_align_p (gdbarch))
sp = gdbarch_frame_align (gdbarch, sp);
}
}
if (hidden_first_param_p)
{
struct value **new_args;
/* Add the new argument to the front of the argument list. */
new_args = XNEWVEC (struct value *, nargs + 1);
new_args[0] = value_from_pointer (lookup_pointer_type (values_type),
struct_addr);
memcpy (&new_args[1], &args[0], sizeof (struct value *) * nargs);
args = new_args;
nargs++;
args_cleanup = make_cleanup (xfree, args);
}
else
args_cleanup = make_cleanup (null_cleanup, NULL);
/* Create the dummy stack frame. Pass in the call dummy address as,
presumably, the ABI code knows where, in the call dummy, the
return address should be pointed. */
sp = gdbarch_push_dummy_call (gdbarch, function, get_current_regcache (),
bp_addr, nargs, args,
sp, struct_return, struct_addr);
do_cleanups (args_cleanup);
/* Set up a frame ID for the dummy frame so we can pass it to
set_momentary_breakpoint. We need to give the breakpoint a frame
ID so that the breakpoint code can correctly re-identify the
dummy breakpoint. */
/* Sanity. The exact same SP value is returned by PUSH_DUMMY_CALL,
saved as the dummy-frame TOS, and used by dummy_id to form
the frame ID's stack address. */
dummy_id = frame_id_build (sp, bp_addr);
/* Create a momentary breakpoint at the return address of the
inferior. That way it breaks when it returns. */
{
symtab_and_line sal;
sal.pspace = current_program_space;
sal.pc = bp_addr;
sal.section = find_pc_overlay (sal.pc);
/* Sanity. The exact same SP value is returned by
PUSH_DUMMY_CALL, saved as the dummy-frame TOS, and used by
dummy_id to form the frame ID's stack address. */
breakpoint *bpt
= set_momentary_breakpoint (gdbarch, sal,
dummy_id, bp_call_dummy).release ();
/* set_momentary_breakpoint invalidates FRAME. */
frame = NULL;
bpt->disposition = disp_del;
gdb_assert (bpt->related_breakpoint == bpt);
breakpoint *longjmp_b = set_longjmp_breakpoint_for_call_dummy ();
if (longjmp_b)
{
/* Link BPT into the chain of LONGJMP_B. */
bpt->related_breakpoint = longjmp_b;
while (longjmp_b->related_breakpoint != bpt->related_breakpoint)
longjmp_b = longjmp_b->related_breakpoint;
longjmp_b->related_breakpoint = bpt;
}
}
/* Create a breakpoint in std::terminate.
If a C++ exception is raised in the dummy-frame, and the
exception handler is (normally, and expected to be) out-of-frame,
the default C++ handler will (wrongly) be called in an inferior
function call. This is wrong, as an exception can be normally
and legally handled out-of-frame. The confines of the dummy frame
prevent the unwinder from finding the correct handler (or any
handler, unless it is in-frame). The default handler calls
std::terminate. This will kill the inferior. Assert that
terminate should never be called in an inferior function
call. Place a momentary breakpoint in the std::terminate function
and if triggered in the call, rewind. */
if (unwind_on_terminating_exception_p)
set_std_terminate_breakpoint ();
/* Discard both inf_status and caller_state cleanups.
From this point on we explicitly restore the associated state
or discard it. */
discard_cleanups (inf_status_cleanup);
/* Everything's ready, push all the info needed to restore the
caller (and identify the dummy-frame) onto the dummy-frame
stack. */
dummy_frame_push (caller_state, &dummy_id, inferior_ptid);
if (dummy_dtor != NULL)
register_dummy_frame_dtor (dummy_id, inferior_ptid,
dummy_dtor, dummy_dtor_data);
/* Register a clean-up for unwind_on_terminating_exception_breakpoint. */
terminate_bp_cleanup = make_cleanup (cleanup_delete_std_terminate_breakpoint,
NULL);
/* - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP - SNIP -
If you're looking to implement asynchronous dummy-frames, then
just below is the place to chop this function in two.. */
/* TP is invalid after run_inferior_call returns, so enclose this
in a block so that it's only in scope during the time it's valid. */
{
struct thread_info *tp = inferior_thread ();
struct thread_fsm *saved_sm;
struct call_thread_fsm *sm;
/* Save the current FSM. We'll override it. */
saved_sm = tp->thread_fsm;
tp->thread_fsm = NULL;
/* Save this thread's ptid, we need it later but the thread
may have exited. */
call_thread_ptid = tp->ptid;
/* Run the inferior until it stops. */
/* Create the FSM used to manage the infcall. It tells infrun to
not report the stop to the user, and captures the return value
before the dummy frame is popped. run_inferior_call registers
it with the thread ASAP. */
sm = new_call_thread_fsm (current_ui, command_interp (),
gdbarch, function,
values_type,
struct_return || hidden_first_param_p,
struct_addr);
e = run_inferior_call (sm, tp, real_pc);
observer_notify_inferior_call_post (call_thread_ptid, funaddr);
tp = find_thread_ptid (call_thread_ptid);
if (tp != NULL)
{
/* The FSM should still be the same. */
gdb_assert (tp->thread_fsm == &sm->thread_fsm);
if (thread_fsm_finished_p (tp->thread_fsm))
{
struct value *retval;
/* The inferior call is successful. Pop the dummy frame,
which runs its destructors and restores the inferior's
suspend state, and restore the inferior control
state. */
dummy_frame_pop (dummy_id, call_thread_ptid);
restore_infcall_control_state (inf_status);
/* Get the return value. */
retval = sm->return_value;
/* Clean up / destroy the call FSM, and restore the
original one. */
thread_fsm_clean_up (tp->thread_fsm, tp);
thread_fsm_delete (tp->thread_fsm);
tp->thread_fsm = saved_sm;
maybe_remove_breakpoints ();
do_cleanups (terminate_bp_cleanup);
gdb_assert (retval != NULL);
return retval;
}
/* Didn't complete. Restore previous state machine, and
handle the error. */
tp->thread_fsm = saved_sm;
}
}
/* Rethrow an error if we got one trying to run the inferior. */
if (e.reason < 0)
{
const char *name = get_function_name (funaddr,
name_buf, sizeof (name_buf));
discard_infcall_control_state (inf_status);
/* We could discard the dummy frame here if the program exited,
but it will get garbage collected the next time the program is
run anyway. */
switch (e.reason)
{
case RETURN_ERROR:
throw_error (e.error, _("%s\n\
An error occurred while in a function called from GDB.\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned.\n\
When the function is done executing, GDB will silently stop."),
e.message, name);
case RETURN_QUIT:
default:
throw_exception (e);
}
}
/* If the program has exited, or we stopped at a different thread,
exit and inform the user. */
if (! target_has_execution)
{
const char *name = get_function_name (funaddr,
name_buf, sizeof (name_buf));
/* If we try to restore the inferior status,
we'll crash as the inferior is no longer running. */
discard_infcall_control_state (inf_status);
/* We could discard the dummy frame here given that the program exited,
but it will get garbage collected the next time the program is
run anyway. */
error (_("The program being debugged exited while in a function "
"called from GDB.\n"
"Evaluation of the expression containing the function\n"
"(%s) will be abandoned."),
name);
}
if (! ptid_equal (call_thread_ptid, inferior_ptid))
{
const char *name = get_function_name (funaddr,
name_buf, sizeof (name_buf));
/* We've switched threads. This can happen if another thread gets a
signal or breakpoint while our thread was running.
There's no point in restoring the inferior status,
we're in a different thread. */
discard_infcall_control_state (inf_status);
/* Keep the dummy frame record, if the user switches back to the
thread with the hand-call, we'll need it. */
if (stopped_by_random_signal)
error (_("\
The program received a signal in another thread while\n\
making a function call from GDB.\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned.\n\
When the function is done executing, GDB will silently stop."),
name);
else
error (_("\
The program stopped in another thread while making a function call from GDB.\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned.\n\
When the function is done executing, GDB will silently stop."),
name);
}
{
/* Make a copy as NAME may be in an objfile freed by dummy_frame_pop. */
std::string name = get_function_name (funaddr, name_buf,
sizeof (name_buf));
if (stopped_by_random_signal)
{
/* We stopped inside the FUNCTION because of a random
signal. Further execution of the FUNCTION is not
allowed. */
if (unwind_on_signal_p)
{
/* The user wants the context restored. */
/* We must get back to the frame we were before the
dummy call. */
dummy_frame_pop (dummy_id, call_thread_ptid);
/* We also need to restore inferior status to that before the
dummy call. */
restore_infcall_control_state (inf_status);
/* FIXME: Insert a bunch of wrap_here; name can be very
long if it's a C++ name with arguments and stuff. */
error (_("\
The program being debugged was signaled while in a function called from GDB.\n\
GDB has restored the context to what it was before the call.\n\
To change this behavior use \"set unwindonsignal off\".\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned."),
name.c_str ());
}
else
{
/* The user wants to stay in the frame where we stopped
(default).
Discard inferior status, we're not at the same point
we started at. */
discard_infcall_control_state (inf_status);
/* FIXME: Insert a bunch of wrap_here; name can be very
long if it's a C++ name with arguments and stuff. */
error (_("\
The program being debugged was signaled while in a function called from GDB.\n\
GDB remains in the frame where the signal was received.\n\
To change this behavior use \"set unwindonsignal on\".\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned.\n\
When the function is done executing, GDB will silently stop."),
name.c_str ());
}
}
if (stop_stack_dummy == STOP_STD_TERMINATE)
{
/* We must get back to the frame we were before the dummy
call. */
dummy_frame_pop (dummy_id, call_thread_ptid);
/* We also need to restore inferior status to that before
the dummy call. */
restore_infcall_control_state (inf_status);
error (_("\
The program being debugged entered a std::terminate call, most likely\n\
caused by an unhandled C++ exception. GDB blocked this call in order\n\
to prevent the program from being terminated, and has restored the\n\
context to its original state before the call.\n\
To change this behaviour use \"set unwind-on-terminating-exception off\".\n\
Evaluation of the expression containing the function (%s)\n\
will be abandoned."),
name.c_str ());
}
else if (stop_stack_dummy == STOP_NONE)
{
/* We hit a breakpoint inside the FUNCTION.
Keep the dummy frame, the user may want to examine its state.
Discard inferior status, we're not at the same point
we started at. */
discard_infcall_control_state (inf_status);
/* The following error message used to say "The expression
which contained the function call has been discarded."
It is a hard concept to explain in a few words. Ideally,
GDB would be able to resume evaluation of the expression
when the function finally is done executing. Perhaps
someday this will be implemented (it would not be easy). */
/* FIXME: Insert a bunch of wrap_here; name can be very long if it's
a C++ name with arguments and stuff. */
error (_("\
The program being debugged stopped while in a function called from GDB.\n\
Evaluation of the expression containing the function\n\
(%s) will be abandoned.\n\
When the function is done executing, GDB will silently stop."),
name.c_str ());
}
}
/* The above code errors out, so ... */
gdb_assert_not_reached ("... should not be here");
}
void
_initialize_infcall (void)
{
add_setshow_boolean_cmd ("coerce-float-to-double", class_obscure,
&coerce_float_to_double_p, _("\
Set coercion of floats to doubles when calling functions."), _("\
Show coercion of floats to doubles when calling functions"), _("\
Variables of type float should generally be converted to doubles before\n\
calling an unprototyped function, and left alone when calling a prototyped\n\
function. However, some older debug info formats do not provide enough\n\
information to determine that a function is prototyped. If this flag is\n\
set, GDB will perform the conversion for a function it considers\n\
unprototyped.\n\
The default is to perform the conversion.\n"),
NULL,
show_coerce_float_to_double_p,
&setlist, &showlist);
add_setshow_boolean_cmd ("unwindonsignal", no_class,
&unwind_on_signal_p, _("\
Set unwinding of stack if a signal is received while in a call dummy."), _("\
Show unwinding of stack if a signal is received while in a call dummy."), _("\
The unwindonsignal lets the user determine what gdb should do if a signal\n\
is received while in a function called from gdb (call dummy). If set, gdb\n\
unwinds the stack and restore the context to what as it was before the call.\n\
The default is to stop in the frame where the signal was received."),
NULL,
show_unwind_on_signal_p,
&setlist, &showlist);
add_setshow_boolean_cmd ("unwind-on-terminating-exception", no_class,
&unwind_on_terminating_exception_p, _("\
Set unwinding of stack if std::terminate is called while in call dummy."), _("\
Show unwinding of stack if std::terminate() is called while in a call dummy."),
_("\
The unwind on terminating exception flag lets the user determine\n\
what gdb should do if a std::terminate() call is made from the\n\
default exception handler. If set, gdb unwinds the stack and restores\n\
the context to what it was before the call. If unset, gdb allows the\n\
std::terminate call to proceed.\n\
The default is to unwind the frame."),
NULL,
show_unwind_on_terminating_exception_p,
&setlist, &showlist);
}
|