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Fix gdb crash when trying to print the address of a synthetic C++ reference
[thirdparty/binutils-gdb.git] / gdb / valops.c
1 /* Perform non-arithmetic operations on values, for GDB.
2
3 Copyright (C) 1986-2016 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "symtab.h"
22 #include "gdbtypes.h"
23 #include "value.h"
24 #include "frame.h"
25 #include "inferior.h"
26 #include "gdbcore.h"
27 #include "target.h"
28 #include "demangle.h"
29 #include "language.h"
30 #include "gdbcmd.h"
31 #include "regcache.h"
32 #include "cp-abi.h"
33 #include "block.h"
34 #include "infcall.h"
35 #include "dictionary.h"
36 #include "cp-support.h"
37 #include "dfp.h"
38 #include "tracepoint.h"
39 #include "observer.h"
40 #include "objfiles.h"
41 #include "extension.h"
42
43 extern unsigned int overload_debug;
44 /* Local functions. */
45
46 static int typecmp (int staticp, int varargs, int nargs,
47 struct field t1[], struct value *t2[]);
48
49 static struct value *search_struct_field (const char *, struct value *,
50 struct type *, int);
51
52 static struct value *search_struct_method (const char *, struct value **,
53 struct value **,
54 int, int *, struct type *);
55
56 static int find_oload_champ_namespace (struct value **, int,
57 const char *, const char *,
58 struct symbol ***,
59 struct badness_vector **,
60 const int no_adl);
61
62 static
63 int find_oload_champ_namespace_loop (struct value **, int,
64 const char *, const char *,
65 int, struct symbol ***,
66 struct badness_vector **, int *,
67 const int no_adl);
68
69 static int find_oload_champ (struct value **, int, int,
70 struct fn_field *, VEC (xmethod_worker_ptr) *,
71 struct symbol **, struct badness_vector **);
72
73 static int oload_method_static_p (struct fn_field *, int);
74
75 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
76
77 static enum
78 oload_classification classify_oload_match (struct badness_vector *,
79 int, int);
80
81 static struct value *value_struct_elt_for_reference (struct type *,
82 int, struct type *,
83 const char *,
84 struct type *,
85 int, enum noside);
86
87 static struct value *value_namespace_elt (const struct type *,
88 const char *, int , enum noside);
89
90 static struct value *value_maybe_namespace_elt (const struct type *,
91 const char *, int,
92 enum noside);
93
94 static CORE_ADDR allocate_space_in_inferior (int);
95
96 static struct value *cast_into_complex (struct type *, struct value *);
97
98 static void find_method_list (struct value **, const char *,
99 int, struct type *, struct fn_field **, int *,
100 VEC (xmethod_worker_ptr) **,
101 struct type **, int *);
102
103 void _initialize_valops (void);
104
105 #if 0
106 /* Flag for whether we want to abandon failed expression evals by
107 default. */
108
109 static int auto_abandon = 0;
110 #endif
111
112 int overload_resolution = 0;
113 static void
114 show_overload_resolution (struct ui_file *file, int from_tty,
115 struct cmd_list_element *c,
116 const char *value)
117 {
118 fprintf_filtered (file, _("Overload resolution in evaluating "
119 "C++ functions is %s.\n"),
120 value);
121 }
122
123 /* Find the address of function name NAME in the inferior. If OBJF_P
124 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
125 is defined. */
126
127 struct value *
128 find_function_in_inferior (const char *name, struct objfile **objf_p)
129 {
130 struct block_symbol sym;
131
132 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
133 if (sym.symbol != NULL)
134 {
135 if (SYMBOL_CLASS (sym.symbol) != LOC_BLOCK)
136 {
137 error (_("\"%s\" exists in this program but is not a function."),
138 name);
139 }
140
141 if (objf_p)
142 *objf_p = symbol_objfile (sym.symbol);
143
144 return value_of_variable (sym.symbol, sym.block);
145 }
146 else
147 {
148 struct bound_minimal_symbol msymbol =
149 lookup_bound_minimal_symbol (name);
150
151 if (msymbol.minsym != NULL)
152 {
153 struct objfile *objfile = msymbol.objfile;
154 struct gdbarch *gdbarch = get_objfile_arch (objfile);
155
156 struct type *type;
157 CORE_ADDR maddr;
158 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
159 type = lookup_function_type (type);
160 type = lookup_pointer_type (type);
161 maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
162
163 if (objf_p)
164 *objf_p = objfile;
165
166 return value_from_pointer (type, maddr);
167 }
168 else
169 {
170 if (!target_has_execution)
171 error (_("evaluation of this expression "
172 "requires the target program to be active"));
173 else
174 error (_("evaluation of this expression requires the "
175 "program to have a function \"%s\"."),
176 name);
177 }
178 }
179 }
180
181 /* Allocate NBYTES of space in the inferior using the inferior's
182 malloc and return a value that is a pointer to the allocated
183 space. */
184
185 struct value *
186 value_allocate_space_in_inferior (int len)
187 {
188 struct objfile *objf;
189 struct value *val = find_function_in_inferior ("malloc", &objf);
190 struct gdbarch *gdbarch = get_objfile_arch (objf);
191 struct value *blocklen;
192
193 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
194 val = call_function_by_hand (val, 1, &blocklen);
195 if (value_logical_not (val))
196 {
197 if (!target_has_execution)
198 error (_("No memory available to program now: "
199 "you need to start the target first"));
200 else
201 error (_("No memory available to program: call to malloc failed"));
202 }
203 return val;
204 }
205
206 static CORE_ADDR
207 allocate_space_in_inferior (int len)
208 {
209 return value_as_long (value_allocate_space_in_inferior (len));
210 }
211
212 /* Cast struct value VAL to type TYPE and return as a value.
213 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
214 for this to work. Typedef to one of the codes is permitted.
215 Returns NULL if the cast is neither an upcast nor a downcast. */
216
217 static struct value *
218 value_cast_structs (struct type *type, struct value *v2)
219 {
220 struct type *t1;
221 struct type *t2;
222 struct value *v;
223
224 gdb_assert (type != NULL && v2 != NULL);
225
226 t1 = check_typedef (type);
227 t2 = check_typedef (value_type (v2));
228
229 /* Check preconditions. */
230 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
231 || TYPE_CODE (t1) == TYPE_CODE_UNION)
232 && !!"Precondition is that type is of STRUCT or UNION kind.");
233 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
234 || TYPE_CODE (t2) == TYPE_CODE_UNION)
235 && !!"Precondition is that value is of STRUCT or UNION kind");
236
237 if (TYPE_NAME (t1) != NULL
238 && TYPE_NAME (t2) != NULL
239 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
240 return NULL;
241
242 /* Upcasting: look in the type of the source to see if it contains the
243 type of the target as a superclass. If so, we'll need to
244 offset the pointer rather than just change its type. */
245 if (TYPE_NAME (t1) != NULL)
246 {
247 v = search_struct_field (type_name_no_tag (t1),
248 v2, t2, 1);
249 if (v)
250 return v;
251 }
252
253 /* Downcasting: look in the type of the target to see if it contains the
254 type of the source as a superclass. If so, we'll need to
255 offset the pointer rather than just change its type. */
256 if (TYPE_NAME (t2) != NULL)
257 {
258 /* Try downcasting using the run-time type of the value. */
259 int full, top, using_enc;
260 struct type *real_type;
261
262 real_type = value_rtti_type (v2, &full, &top, &using_enc);
263 if (real_type)
264 {
265 v = value_full_object (v2, real_type, full, top, using_enc);
266 v = value_at_lazy (real_type, value_address (v));
267 real_type = value_type (v);
268
269 /* We might be trying to cast to the outermost enclosing
270 type, in which case search_struct_field won't work. */
271 if (TYPE_NAME (real_type) != NULL
272 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
273 return v;
274
275 v = search_struct_field (type_name_no_tag (t2), v, real_type, 1);
276 if (v)
277 return v;
278 }
279
280 /* Try downcasting using information from the destination type
281 T2. This wouldn't work properly for classes with virtual
282 bases, but those were handled above. */
283 v = search_struct_field (type_name_no_tag (t2),
284 value_zero (t1, not_lval), t1, 1);
285 if (v)
286 {
287 /* Downcasting is possible (t1 is superclass of v2). */
288 CORE_ADDR addr2 = value_address (v2);
289
290 addr2 -= value_address (v) + value_embedded_offset (v);
291 return value_at (type, addr2);
292 }
293 }
294
295 return NULL;
296 }
297
298 /* Cast one pointer or reference type to another. Both TYPE and
299 the type of ARG2 should be pointer types, or else both should be
300 reference types. If SUBCLASS_CHECK is non-zero, this will force a
301 check to see whether TYPE is a superclass of ARG2's type. If
302 SUBCLASS_CHECK is zero, then the subclass check is done only when
303 ARG2 is itself non-zero. Returns the new pointer or reference. */
304
305 struct value *
306 value_cast_pointers (struct type *type, struct value *arg2,
307 int subclass_check)
308 {
309 struct type *type1 = check_typedef (type);
310 struct type *type2 = check_typedef (value_type (arg2));
311 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
312 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
313
314 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
315 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
316 && (subclass_check || !value_logical_not (arg2)))
317 {
318 struct value *v2;
319
320 if (TYPE_CODE (type2) == TYPE_CODE_REF)
321 v2 = coerce_ref (arg2);
322 else
323 v2 = value_ind (arg2);
324 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
325 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
326 v2 = value_cast_structs (t1, v2);
327 /* At this point we have what we can have, un-dereference if needed. */
328 if (v2)
329 {
330 struct value *v = value_addr (v2);
331
332 deprecated_set_value_type (v, type);
333 return v;
334 }
335 }
336
337 /* No superclass found, just change the pointer type. */
338 arg2 = value_copy (arg2);
339 deprecated_set_value_type (arg2, type);
340 set_value_enclosing_type (arg2, type);
341 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
342 return arg2;
343 }
344
345 /* Cast value ARG2 to type TYPE and return as a value.
346 More general than a C cast: accepts any two types of the same length,
347 and if ARG2 is an lvalue it can be cast into anything at all. */
348 /* In C++, casts may change pointer or object representations. */
349
350 struct value *
351 value_cast (struct type *type, struct value *arg2)
352 {
353 enum type_code code1;
354 enum type_code code2;
355 int scalar;
356 struct type *type2;
357
358 int convert_to_boolean = 0;
359
360 if (value_type (arg2) == type)
361 return arg2;
362
363 code1 = TYPE_CODE (check_typedef (type));
364
365 /* Check if we are casting struct reference to struct reference. */
366 if (code1 == TYPE_CODE_REF)
367 {
368 /* We dereference type; then we recurse and finally
369 we generate value of the given reference. Nothing wrong with
370 that. */
371 struct type *t1 = check_typedef (type);
372 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
373 struct value *val = value_cast (dereftype, arg2);
374
375 return value_ref (val);
376 }
377
378 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
379
380 if (code2 == TYPE_CODE_REF)
381 /* We deref the value and then do the cast. */
382 return value_cast (type, coerce_ref (arg2));
383
384 type = check_typedef (type);
385 code1 = TYPE_CODE (type);
386 arg2 = coerce_ref (arg2);
387 type2 = check_typedef (value_type (arg2));
388
389 /* You can't cast to a reference type. See value_cast_pointers
390 instead. */
391 gdb_assert (code1 != TYPE_CODE_REF);
392
393 /* A cast to an undetermined-length array_type, such as
394 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
395 where N is sizeof(OBJECT)/sizeof(TYPE). */
396 if (code1 == TYPE_CODE_ARRAY)
397 {
398 struct type *element_type = TYPE_TARGET_TYPE (type);
399 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
400
401 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
402 {
403 struct type *range_type = TYPE_INDEX_TYPE (type);
404 int val_length = TYPE_LENGTH (type2);
405 LONGEST low_bound, high_bound, new_length;
406
407 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
408 low_bound = 0, high_bound = 0;
409 new_length = val_length / element_length;
410 if (val_length % element_length != 0)
411 warning (_("array element type size does not "
412 "divide object size in cast"));
413 /* FIXME-type-allocation: need a way to free this type when
414 we are done with it. */
415 range_type = create_static_range_type ((struct type *) NULL,
416 TYPE_TARGET_TYPE (range_type),
417 low_bound,
418 new_length + low_bound - 1);
419 deprecated_set_value_type (arg2,
420 create_array_type ((struct type *) NULL,
421 element_type,
422 range_type));
423 return arg2;
424 }
425 }
426
427 if (current_language->c_style_arrays
428 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
429 && !TYPE_VECTOR (type2))
430 arg2 = value_coerce_array (arg2);
431
432 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
433 arg2 = value_coerce_function (arg2);
434
435 type2 = check_typedef (value_type (arg2));
436 code2 = TYPE_CODE (type2);
437
438 if (code1 == TYPE_CODE_COMPLEX)
439 return cast_into_complex (type, arg2);
440 if (code1 == TYPE_CODE_BOOL)
441 {
442 code1 = TYPE_CODE_INT;
443 convert_to_boolean = 1;
444 }
445 if (code1 == TYPE_CODE_CHAR)
446 code1 = TYPE_CODE_INT;
447 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
448 code2 = TYPE_CODE_INT;
449
450 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
451 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
452 || code2 == TYPE_CODE_RANGE);
453
454 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
455 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
456 && TYPE_NAME (type) != 0)
457 {
458 struct value *v = value_cast_structs (type, arg2);
459
460 if (v)
461 return v;
462 }
463
464 if (code1 == TYPE_CODE_FLT && scalar)
465 return value_from_double (type, value_as_double (arg2));
466 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
467 {
468 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
469 int dec_len = TYPE_LENGTH (type);
470 gdb_byte dec[16];
471
472 if (code2 == TYPE_CODE_FLT)
473 decimal_from_floating (arg2, dec, dec_len, byte_order);
474 else if (code2 == TYPE_CODE_DECFLOAT)
475 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
476 byte_order, dec, dec_len, byte_order);
477 else
478 /* The only option left is an integral type. */
479 decimal_from_integral (arg2, dec, dec_len, byte_order);
480
481 return value_from_decfloat (type, dec);
482 }
483 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
484 || code1 == TYPE_CODE_RANGE)
485 && (scalar || code2 == TYPE_CODE_PTR
486 || code2 == TYPE_CODE_MEMBERPTR))
487 {
488 LONGEST longest;
489
490 /* When we cast pointers to integers, we mustn't use
491 gdbarch_pointer_to_address to find the address the pointer
492 represents, as value_as_long would. GDB should evaluate
493 expressions just as the compiler would --- and the compiler
494 sees a cast as a simple reinterpretation of the pointer's
495 bits. */
496 if (code2 == TYPE_CODE_PTR)
497 longest = extract_unsigned_integer
498 (value_contents (arg2), TYPE_LENGTH (type2),
499 gdbarch_byte_order (get_type_arch (type2)));
500 else
501 longest = value_as_long (arg2);
502 return value_from_longest (type, convert_to_boolean ?
503 (LONGEST) (longest ? 1 : 0) : longest);
504 }
505 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
506 || code2 == TYPE_CODE_ENUM
507 || code2 == TYPE_CODE_RANGE))
508 {
509 /* TYPE_LENGTH (type) is the length of a pointer, but we really
510 want the length of an address! -- we are really dealing with
511 addresses (i.e., gdb representations) not pointers (i.e.,
512 target representations) here.
513
514 This allows things like "print *(int *)0x01000234" to work
515 without printing a misleading message -- which would
516 otherwise occur when dealing with a target having two byte
517 pointers and four byte addresses. */
518
519 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
520 LONGEST longest = value_as_long (arg2);
521
522 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
523 {
524 if (longest >= ((LONGEST) 1 << addr_bit)
525 || longest <= -((LONGEST) 1 << addr_bit))
526 warning (_("value truncated"));
527 }
528 return value_from_longest (type, longest);
529 }
530 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
531 && value_as_long (arg2) == 0)
532 {
533 struct value *result = allocate_value (type);
534
535 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
536 return result;
537 }
538 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
539 && value_as_long (arg2) == 0)
540 {
541 /* The Itanium C++ ABI represents NULL pointers to members as
542 minus one, instead of biasing the normal case. */
543 return value_from_longest (type, -1);
544 }
545 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
546 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
547 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
548 error (_("Cannot convert between vector values of different sizes"));
549 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
550 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
551 error (_("can only cast scalar to vector of same size"));
552 else if (code1 == TYPE_CODE_VOID)
553 {
554 return value_zero (type, not_lval);
555 }
556 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
557 {
558 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
559 return value_cast_pointers (type, arg2, 0);
560
561 arg2 = value_copy (arg2);
562 deprecated_set_value_type (arg2, type);
563 set_value_enclosing_type (arg2, type);
564 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
565 return arg2;
566 }
567 else if (VALUE_LVAL (arg2) == lval_memory)
568 return value_at_lazy (type, value_address (arg2));
569 else
570 {
571 error (_("Invalid cast."));
572 return 0;
573 }
574 }
575
576 /* The C++ reinterpret_cast operator. */
577
578 struct value *
579 value_reinterpret_cast (struct type *type, struct value *arg)
580 {
581 struct value *result;
582 struct type *real_type = check_typedef (type);
583 struct type *arg_type, *dest_type;
584 int is_ref = 0;
585 enum type_code dest_code, arg_code;
586
587 /* Do reference, function, and array conversion. */
588 arg = coerce_array (arg);
589
590 /* Attempt to preserve the type the user asked for. */
591 dest_type = type;
592
593 /* If we are casting to a reference type, transform
594 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
595 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
596 {
597 is_ref = 1;
598 arg = value_addr (arg);
599 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
600 real_type = lookup_pointer_type (real_type);
601 }
602
603 arg_type = value_type (arg);
604
605 dest_code = TYPE_CODE (real_type);
606 arg_code = TYPE_CODE (arg_type);
607
608 /* We can convert pointer types, or any pointer type to int, or int
609 type to pointer. */
610 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
611 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
612 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
613 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
614 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
615 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
616 || (dest_code == arg_code
617 && (dest_code == TYPE_CODE_PTR
618 || dest_code == TYPE_CODE_METHODPTR
619 || dest_code == TYPE_CODE_MEMBERPTR)))
620 result = value_cast (dest_type, arg);
621 else
622 error (_("Invalid reinterpret_cast"));
623
624 if (is_ref)
625 result = value_cast (type, value_ref (value_ind (result)));
626
627 return result;
628 }
629
630 /* A helper for value_dynamic_cast. This implements the first of two
631 runtime checks: we iterate over all the base classes of the value's
632 class which are equal to the desired class; if only one of these
633 holds the value, then it is the answer. */
634
635 static int
636 dynamic_cast_check_1 (struct type *desired_type,
637 const gdb_byte *valaddr,
638 int embedded_offset,
639 CORE_ADDR address,
640 struct value *val,
641 struct type *search_type,
642 CORE_ADDR arg_addr,
643 struct type *arg_type,
644 struct value **result)
645 {
646 int i, result_count = 0;
647
648 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
649 {
650 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
651 address, val);
652
653 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
654 {
655 if (address + embedded_offset + offset >= arg_addr
656 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
657 {
658 ++result_count;
659 if (!*result)
660 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
661 address + embedded_offset + offset);
662 }
663 }
664 else
665 result_count += dynamic_cast_check_1 (desired_type,
666 valaddr,
667 embedded_offset + offset,
668 address, val,
669 TYPE_BASECLASS (search_type, i),
670 arg_addr,
671 arg_type,
672 result);
673 }
674
675 return result_count;
676 }
677
678 /* A helper for value_dynamic_cast. This implements the second of two
679 runtime checks: we look for a unique public sibling class of the
680 argument's declared class. */
681
682 static int
683 dynamic_cast_check_2 (struct type *desired_type,
684 const gdb_byte *valaddr,
685 int embedded_offset,
686 CORE_ADDR address,
687 struct value *val,
688 struct type *search_type,
689 struct value **result)
690 {
691 int i, result_count = 0;
692
693 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
694 {
695 int offset;
696
697 if (! BASETYPE_VIA_PUBLIC (search_type, i))
698 continue;
699
700 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
701 address, val);
702 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
703 {
704 ++result_count;
705 if (*result == NULL)
706 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
707 address + embedded_offset + offset);
708 }
709 else
710 result_count += dynamic_cast_check_2 (desired_type,
711 valaddr,
712 embedded_offset + offset,
713 address, val,
714 TYPE_BASECLASS (search_type, i),
715 result);
716 }
717
718 return result_count;
719 }
720
721 /* The C++ dynamic_cast operator. */
722
723 struct value *
724 value_dynamic_cast (struct type *type, struct value *arg)
725 {
726 int full, top, using_enc;
727 struct type *resolved_type = check_typedef (type);
728 struct type *arg_type = check_typedef (value_type (arg));
729 struct type *class_type, *rtti_type;
730 struct value *result, *tem, *original_arg = arg;
731 CORE_ADDR addr;
732 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
733
734 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
735 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
736 error (_("Argument to dynamic_cast must be a pointer or reference type"));
737 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
738 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_STRUCT)
739 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
740
741 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
742 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
743 {
744 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
745 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
746 && value_as_long (arg) == 0))
747 error (_("Argument to dynamic_cast does not have pointer type"));
748 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
749 {
750 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
751 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
752 error (_("Argument to dynamic_cast does "
753 "not have pointer to class type"));
754 }
755
756 /* Handle NULL pointers. */
757 if (value_as_long (arg) == 0)
758 return value_zero (type, not_lval);
759
760 arg = value_ind (arg);
761 }
762 else
763 {
764 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
765 error (_("Argument to dynamic_cast does not have class type"));
766 }
767
768 /* If the classes are the same, just return the argument. */
769 if (class_types_same_p (class_type, arg_type))
770 return value_cast (type, arg);
771
772 /* If the target type is a unique base class of the argument's
773 declared type, just cast it. */
774 if (is_ancestor (class_type, arg_type))
775 {
776 if (is_unique_ancestor (class_type, arg))
777 return value_cast (type, original_arg);
778 error (_("Ambiguous dynamic_cast"));
779 }
780
781 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
782 if (! rtti_type)
783 error (_("Couldn't determine value's most derived type for dynamic_cast"));
784
785 /* Compute the most derived object's address. */
786 addr = value_address (arg);
787 if (full)
788 {
789 /* Done. */
790 }
791 else if (using_enc)
792 addr += top;
793 else
794 addr += top + value_embedded_offset (arg);
795
796 /* dynamic_cast<void *> means to return a pointer to the
797 most-derived object. */
798 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
799 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
800 return value_at_lazy (type, addr);
801
802 tem = value_at (type, addr);
803 type = value_type (tem);
804
805 /* The first dynamic check specified in 5.2.7. */
806 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
807 {
808 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
809 return tem;
810 result = NULL;
811 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
812 value_contents_for_printing (tem),
813 value_embedded_offset (tem),
814 value_address (tem), tem,
815 rtti_type, addr,
816 arg_type,
817 &result) == 1)
818 return value_cast (type,
819 is_ref ? value_ref (result) : value_addr (result));
820 }
821
822 /* The second dynamic check specified in 5.2.7. */
823 result = NULL;
824 if (is_public_ancestor (arg_type, rtti_type)
825 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
826 value_contents_for_printing (tem),
827 value_embedded_offset (tem),
828 value_address (tem), tem,
829 rtti_type, &result) == 1)
830 return value_cast (type,
831 is_ref ? value_ref (result) : value_addr (result));
832
833 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
834 return value_zero (type, not_lval);
835
836 error (_("dynamic_cast failed"));
837 }
838
839 /* Create a value of type TYPE that is zero, and return it. */
840
841 struct value *
842 value_zero (struct type *type, enum lval_type lv)
843 {
844 struct value *val = allocate_value (type);
845
846 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
847 return val;
848 }
849
850 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
851
852 struct value *
853 value_one (struct type *type)
854 {
855 struct type *type1 = check_typedef (type);
856 struct value *val;
857
858 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
859 {
860 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
861 gdb_byte v[16];
862
863 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
864 val = value_from_decfloat (type, v);
865 }
866 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
867 {
868 val = value_from_double (type, (DOUBLEST) 1);
869 }
870 else if (is_integral_type (type1))
871 {
872 val = value_from_longest (type, (LONGEST) 1);
873 }
874 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
875 {
876 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
877 int i;
878 LONGEST low_bound, high_bound;
879 struct value *tmp;
880
881 if (!get_array_bounds (type1, &low_bound, &high_bound))
882 error (_("Could not determine the vector bounds"));
883
884 val = allocate_value (type);
885 for (i = 0; i < high_bound - low_bound + 1; i++)
886 {
887 tmp = value_one (eltype);
888 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
889 value_contents_all (tmp), TYPE_LENGTH (eltype));
890 }
891 }
892 else
893 {
894 error (_("Not a numeric type."));
895 }
896
897 /* value_one result is never used for assignments to. */
898 gdb_assert (VALUE_LVAL (val) == not_lval);
899
900 return val;
901 }
902
903 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
904 The type of the created value may differ from the passed type TYPE.
905 Make sure to retrieve the returned values's new type after this call
906 e.g. in case the type is a variable length array. */
907
908 static struct value *
909 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
910 {
911 struct value *val;
912
913 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
914 error (_("Attempt to dereference a generic pointer."));
915
916 val = value_from_contents_and_address (type, NULL, addr);
917
918 if (!lazy)
919 value_fetch_lazy (val);
920
921 return val;
922 }
923
924 /* Return a value with type TYPE located at ADDR.
925
926 Call value_at only if the data needs to be fetched immediately;
927 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
928 value_at_lazy instead. value_at_lazy simply records the address of
929 the data and sets the lazy-evaluation-required flag. The lazy flag
930 is tested in the value_contents macro, which is used if and when
931 the contents are actually required. The type of the created value
932 may differ from the passed type TYPE. Make sure to retrieve the
933 returned values's new type after this call e.g. in case the type
934 is a variable length array.
935
936 Note: value_at does *NOT* handle embedded offsets; perform such
937 adjustments before or after calling it. */
938
939 struct value *
940 value_at (struct type *type, CORE_ADDR addr)
941 {
942 return get_value_at (type, addr, 0);
943 }
944
945 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
946 The type of the created value may differ from the passed type TYPE.
947 Make sure to retrieve the returned values's new type after this call
948 e.g. in case the type is a variable length array. */
949
950 struct value *
951 value_at_lazy (struct type *type, CORE_ADDR addr)
952 {
953 return get_value_at (type, addr, 1);
954 }
955
956 void
957 read_value_memory (struct value *val, int embedded_offset,
958 int stack, CORE_ADDR memaddr,
959 gdb_byte *buffer, size_t length)
960 {
961 ULONGEST xfered_total = 0;
962 struct gdbarch *arch = get_value_arch (val);
963 int unit_size = gdbarch_addressable_memory_unit_size (arch);
964
965 while (xfered_total < length)
966 {
967 enum target_xfer_status status;
968 ULONGEST xfered_partial;
969
970 status = target_xfer_partial (current_target.beneath,
971 TARGET_OBJECT_MEMORY, NULL,
972 buffer + xfered_total * unit_size, NULL,
973 memaddr + xfered_total,
974 length - xfered_total,
975 &xfered_partial);
976
977 if (status == TARGET_XFER_OK)
978 /* nothing */;
979 else if (status == TARGET_XFER_UNAVAILABLE)
980 mark_value_bytes_unavailable (val, embedded_offset + xfered_total,
981 xfered_partial);
982 else if (status == TARGET_XFER_EOF)
983 memory_error (TARGET_XFER_E_IO, memaddr + xfered_total);
984 else
985 memory_error (status, memaddr + xfered_total);
986
987 xfered_total += xfered_partial;
988 QUIT;
989 }
990 }
991
992 /* Store the contents of FROMVAL into the location of TOVAL.
993 Return a new value with the location of TOVAL and contents of FROMVAL. */
994
995 struct value *
996 value_assign (struct value *toval, struct value *fromval)
997 {
998 struct type *type;
999 struct value *val;
1000 struct frame_id old_frame;
1001
1002 if (!deprecated_value_modifiable (toval))
1003 error (_("Left operand of assignment is not a modifiable lvalue."));
1004
1005 toval = coerce_ref (toval);
1006
1007 type = value_type (toval);
1008 if (VALUE_LVAL (toval) != lval_internalvar)
1009 fromval = value_cast (type, fromval);
1010 else
1011 {
1012 /* Coerce arrays and functions to pointers, except for arrays
1013 which only live in GDB's storage. */
1014 if (!value_must_coerce_to_target (fromval))
1015 fromval = coerce_array (fromval);
1016 }
1017
1018 type = check_typedef (type);
1019
1020 /* Since modifying a register can trash the frame chain, and
1021 modifying memory can trash the frame cache, we save the old frame
1022 and then restore the new frame afterwards. */
1023 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1024
1025 switch (VALUE_LVAL (toval))
1026 {
1027 case lval_internalvar:
1028 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1029 return value_of_internalvar (get_type_arch (type),
1030 VALUE_INTERNALVAR (toval));
1031
1032 case lval_internalvar_component:
1033 {
1034 int offset = value_offset (toval);
1035
1036 /* Are we dealing with a bitfield?
1037
1038 It is important to mention that `value_parent (toval)' is
1039 non-NULL iff `value_bitsize (toval)' is non-zero. */
1040 if (value_bitsize (toval))
1041 {
1042 /* VALUE_INTERNALVAR below refers to the parent value, while
1043 the offset is relative to this parent value. */
1044 gdb_assert (value_parent (value_parent (toval)) == NULL);
1045 offset += value_offset (value_parent (toval));
1046 }
1047
1048 set_internalvar_component (VALUE_INTERNALVAR (toval),
1049 offset,
1050 value_bitpos (toval),
1051 value_bitsize (toval),
1052 fromval);
1053 }
1054 break;
1055
1056 case lval_memory:
1057 {
1058 const gdb_byte *dest_buffer;
1059 CORE_ADDR changed_addr;
1060 int changed_len;
1061 gdb_byte buffer[sizeof (LONGEST)];
1062
1063 if (value_bitsize (toval))
1064 {
1065 struct value *parent = value_parent (toval);
1066
1067 changed_addr = value_address (parent) + value_offset (toval);
1068 changed_len = (value_bitpos (toval)
1069 + value_bitsize (toval)
1070 + HOST_CHAR_BIT - 1)
1071 / HOST_CHAR_BIT;
1072
1073 /* If we can read-modify-write exactly the size of the
1074 containing type (e.g. short or int) then do so. This
1075 is safer for volatile bitfields mapped to hardware
1076 registers. */
1077 if (changed_len < TYPE_LENGTH (type)
1078 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1079 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1080 changed_len = TYPE_LENGTH (type);
1081
1082 if (changed_len > (int) sizeof (LONGEST))
1083 error (_("Can't handle bitfields which "
1084 "don't fit in a %d bit word."),
1085 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1086
1087 read_memory (changed_addr, buffer, changed_len);
1088 modify_field (type, buffer, value_as_long (fromval),
1089 value_bitpos (toval), value_bitsize (toval));
1090 dest_buffer = buffer;
1091 }
1092 else
1093 {
1094 changed_addr = value_address (toval);
1095 changed_len = type_length_units (type);
1096 dest_buffer = value_contents (fromval);
1097 }
1098
1099 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1100 }
1101 break;
1102
1103 case lval_register:
1104 {
1105 struct frame_info *frame;
1106 struct gdbarch *gdbarch;
1107 int value_reg;
1108
1109 /* Figure out which frame this is in currently. */
1110 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1111 value_reg = VALUE_REGNUM (toval);
1112
1113 if (!frame)
1114 error (_("Value being assigned to is no longer active."));
1115
1116 gdbarch = get_frame_arch (frame);
1117
1118 if (value_bitsize (toval))
1119 {
1120 struct value *parent = value_parent (toval);
1121 int offset = value_offset (parent) + value_offset (toval);
1122 int changed_len;
1123 gdb_byte buffer[sizeof (LONGEST)];
1124 int optim, unavail;
1125
1126 changed_len = (value_bitpos (toval)
1127 + value_bitsize (toval)
1128 + HOST_CHAR_BIT - 1)
1129 / HOST_CHAR_BIT;
1130
1131 if (changed_len > (int) sizeof (LONGEST))
1132 error (_("Can't handle bitfields which "
1133 "don't fit in a %d bit word."),
1134 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1135
1136 if (!get_frame_register_bytes (frame, value_reg, offset,
1137 changed_len, buffer,
1138 &optim, &unavail))
1139 {
1140 if (optim)
1141 throw_error (OPTIMIZED_OUT_ERROR,
1142 _("value has been optimized out"));
1143 if (unavail)
1144 throw_error (NOT_AVAILABLE_ERROR,
1145 _("value is not available"));
1146 }
1147
1148 modify_field (type, buffer, value_as_long (fromval),
1149 value_bitpos (toval), value_bitsize (toval));
1150
1151 put_frame_register_bytes (frame, value_reg, offset,
1152 changed_len, buffer);
1153 }
1154 else
1155 {
1156 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1157 type))
1158 {
1159 /* If TOVAL is a special machine register requiring
1160 conversion of program values to a special raw
1161 format. */
1162 gdbarch_value_to_register (gdbarch, frame,
1163 VALUE_REGNUM (toval), type,
1164 value_contents (fromval));
1165 }
1166 else
1167 {
1168 put_frame_register_bytes (frame, value_reg,
1169 value_offset (toval),
1170 TYPE_LENGTH (type),
1171 value_contents (fromval));
1172 }
1173 }
1174
1175 observer_notify_register_changed (frame, value_reg);
1176 break;
1177 }
1178
1179 case lval_computed:
1180 {
1181 const struct lval_funcs *funcs = value_computed_funcs (toval);
1182
1183 if (funcs->write != NULL)
1184 {
1185 funcs->write (toval, fromval);
1186 break;
1187 }
1188 }
1189 /* Fall through. */
1190
1191 default:
1192 error (_("Left operand of assignment is not an lvalue."));
1193 }
1194
1195 /* Assigning to the stack pointer, frame pointer, and other
1196 (architecture and calling convention specific) registers may
1197 cause the frame cache and regcache to be out of date. Assigning to memory
1198 also can. We just do this on all assignments to registers or
1199 memory, for simplicity's sake; I doubt the slowdown matters. */
1200 switch (VALUE_LVAL (toval))
1201 {
1202 case lval_memory:
1203 case lval_register:
1204 case lval_computed:
1205
1206 observer_notify_target_changed (&current_target);
1207
1208 /* Having destroyed the frame cache, restore the selected
1209 frame. */
1210
1211 /* FIXME: cagney/2002-11-02: There has to be a better way of
1212 doing this. Instead of constantly saving/restoring the
1213 frame. Why not create a get_selected_frame() function that,
1214 having saved the selected frame's ID can automatically
1215 re-find the previously selected frame automatically. */
1216
1217 {
1218 struct frame_info *fi = frame_find_by_id (old_frame);
1219
1220 if (fi != NULL)
1221 select_frame (fi);
1222 }
1223
1224 break;
1225 default:
1226 break;
1227 }
1228
1229 /* If the field does not entirely fill a LONGEST, then zero the sign
1230 bits. If the field is signed, and is negative, then sign
1231 extend. */
1232 if ((value_bitsize (toval) > 0)
1233 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1234 {
1235 LONGEST fieldval = value_as_long (fromval);
1236 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1237
1238 fieldval &= valmask;
1239 if (!TYPE_UNSIGNED (type)
1240 && (fieldval & (valmask ^ (valmask >> 1))))
1241 fieldval |= ~valmask;
1242
1243 fromval = value_from_longest (type, fieldval);
1244 }
1245
1246 /* The return value is a copy of TOVAL so it shares its location
1247 information, but its contents are updated from FROMVAL. This
1248 implies the returned value is not lazy, even if TOVAL was. */
1249 val = value_copy (toval);
1250 set_value_lazy (val, 0);
1251 memcpy (value_contents_raw (val), value_contents (fromval),
1252 TYPE_LENGTH (type));
1253
1254 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1255 in the case of pointer types. For object types, the enclosing type
1256 and embedded offset must *not* be copied: the target object refered
1257 to by TOVAL retains its original dynamic type after assignment. */
1258 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1259 {
1260 set_value_enclosing_type (val, value_enclosing_type (fromval));
1261 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1262 }
1263
1264 return val;
1265 }
1266
1267 /* Extend a value VAL to COUNT repetitions of its type. */
1268
1269 struct value *
1270 value_repeat (struct value *arg1, int count)
1271 {
1272 struct value *val;
1273
1274 if (VALUE_LVAL (arg1) != lval_memory)
1275 error (_("Only values in memory can be extended with '@'."));
1276 if (count < 1)
1277 error (_("Invalid number %d of repetitions."), count);
1278
1279 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1280
1281 VALUE_LVAL (val) = lval_memory;
1282 set_value_address (val, value_address (arg1));
1283
1284 read_value_memory (val, 0, value_stack (val), value_address (val),
1285 value_contents_all_raw (val),
1286 type_length_units (value_enclosing_type (val)));
1287
1288 return val;
1289 }
1290
1291 struct value *
1292 value_of_variable (struct symbol *var, const struct block *b)
1293 {
1294 struct frame_info *frame = NULL;
1295
1296 if (symbol_read_needs_frame (var))
1297 frame = get_selected_frame (_("No frame selected."));
1298
1299 return read_var_value (var, b, frame);
1300 }
1301
1302 struct value *
1303 address_of_variable (struct symbol *var, const struct block *b)
1304 {
1305 struct type *type = SYMBOL_TYPE (var);
1306 struct value *val;
1307
1308 /* Evaluate it first; if the result is a memory address, we're fine.
1309 Lazy evaluation pays off here. */
1310
1311 val = value_of_variable (var, b);
1312 type = value_type (val);
1313
1314 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1315 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1316 {
1317 CORE_ADDR addr = value_address (val);
1318
1319 return value_from_pointer (lookup_pointer_type (type), addr);
1320 }
1321
1322 /* Not a memory address; check what the problem was. */
1323 switch (VALUE_LVAL (val))
1324 {
1325 case lval_register:
1326 {
1327 struct frame_info *frame;
1328 const char *regname;
1329
1330 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1331 gdb_assert (frame);
1332
1333 regname = gdbarch_register_name (get_frame_arch (frame),
1334 VALUE_REGNUM (val));
1335 gdb_assert (regname && *regname);
1336
1337 error (_("Address requested for identifier "
1338 "\"%s\" which is in register $%s"),
1339 SYMBOL_PRINT_NAME (var), regname);
1340 break;
1341 }
1342
1343 default:
1344 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1345 SYMBOL_PRINT_NAME (var));
1346 break;
1347 }
1348
1349 return val;
1350 }
1351
1352 /* Return one if VAL does not live in target memory, but should in order
1353 to operate on it. Otherwise return zero. */
1354
1355 int
1356 value_must_coerce_to_target (struct value *val)
1357 {
1358 struct type *valtype;
1359
1360 /* The only lval kinds which do not live in target memory. */
1361 if (VALUE_LVAL (val) != not_lval
1362 && VALUE_LVAL (val) != lval_internalvar
1363 && VALUE_LVAL (val) != lval_xcallable)
1364 return 0;
1365
1366 valtype = check_typedef (value_type (val));
1367
1368 switch (TYPE_CODE (valtype))
1369 {
1370 case TYPE_CODE_ARRAY:
1371 return TYPE_VECTOR (valtype) ? 0 : 1;
1372 case TYPE_CODE_STRING:
1373 return 1;
1374 default:
1375 return 0;
1376 }
1377 }
1378
1379 /* Make sure that VAL lives in target memory if it's supposed to. For
1380 instance, strings are constructed as character arrays in GDB's
1381 storage, and this function copies them to the target. */
1382
1383 struct value *
1384 value_coerce_to_target (struct value *val)
1385 {
1386 LONGEST length;
1387 CORE_ADDR addr;
1388
1389 if (!value_must_coerce_to_target (val))
1390 return val;
1391
1392 length = TYPE_LENGTH (check_typedef (value_type (val)));
1393 addr = allocate_space_in_inferior (length);
1394 write_memory (addr, value_contents (val), length);
1395 return value_at_lazy (value_type (val), addr);
1396 }
1397
1398 /* Given a value which is an array, return a value which is a pointer
1399 to its first element, regardless of whether or not the array has a
1400 nonzero lower bound.
1401
1402 FIXME: A previous comment here indicated that this routine should
1403 be substracting the array's lower bound. It's not clear to me that
1404 this is correct. Given an array subscripting operation, it would
1405 certainly work to do the adjustment here, essentially computing:
1406
1407 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1408
1409 However I believe a more appropriate and logical place to account
1410 for the lower bound is to do so in value_subscript, essentially
1411 computing:
1412
1413 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1414
1415 As further evidence consider what would happen with operations
1416 other than array subscripting, where the caller would get back a
1417 value that had an address somewhere before the actual first element
1418 of the array, and the information about the lower bound would be
1419 lost because of the coercion to pointer type. */
1420
1421 struct value *
1422 value_coerce_array (struct value *arg1)
1423 {
1424 struct type *type = check_typedef (value_type (arg1));
1425
1426 /* If the user tries to do something requiring a pointer with an
1427 array that has not yet been pushed to the target, then this would
1428 be a good time to do so. */
1429 arg1 = value_coerce_to_target (arg1);
1430
1431 if (VALUE_LVAL (arg1) != lval_memory)
1432 error (_("Attempt to take address of value not located in memory."));
1433
1434 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1435 value_address (arg1));
1436 }
1437
1438 /* Given a value which is a function, return a value which is a pointer
1439 to it. */
1440
1441 struct value *
1442 value_coerce_function (struct value *arg1)
1443 {
1444 struct value *retval;
1445
1446 if (VALUE_LVAL (arg1) != lval_memory)
1447 error (_("Attempt to take address of value not located in memory."));
1448
1449 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1450 value_address (arg1));
1451 return retval;
1452 }
1453
1454 /* Return a pointer value for the object for which ARG1 is the
1455 contents. */
1456
1457 struct value *
1458 value_addr (struct value *arg1)
1459 {
1460 struct value *arg2;
1461 struct type *type = check_typedef (value_type (arg1));
1462
1463 if (TYPE_CODE (type) == TYPE_CODE_REF)
1464 {
1465 /* Copy the value, but change the type from (T&) to (T*). We
1466 keep the same location information, which is efficient, and
1467 allows &(&X) to get the location containing the reference.
1468 Do the same to its enclosing type for consistency. */
1469 struct type *type_ptr
1470 = lookup_pointer_type (TYPE_TARGET_TYPE (type));
1471 struct type *enclosing_type
1472 = check_typedef (value_enclosing_type (arg1));
1473 struct type *enclosing_type_ptr
1474 = lookup_pointer_type (TYPE_TARGET_TYPE (enclosing_type));
1475
1476 arg2 = value_copy (arg1);
1477 deprecated_set_value_type (arg2, type_ptr);
1478 set_value_enclosing_type (arg2, enclosing_type_ptr);
1479
1480 return arg2;
1481 }
1482 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1483 return value_coerce_function (arg1);
1484
1485 /* If this is an array that has not yet been pushed to the target,
1486 then this would be a good time to force it to memory. */
1487 arg1 = value_coerce_to_target (arg1);
1488
1489 if (VALUE_LVAL (arg1) != lval_memory)
1490 error (_("Attempt to take address of value not located in memory."));
1491
1492 /* Get target memory address. */
1493 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1494 (value_address (arg1)
1495 + value_embedded_offset (arg1)));
1496
1497 /* This may be a pointer to a base subobject; so remember the
1498 full derived object's type ... */
1499 set_value_enclosing_type (arg2,
1500 lookup_pointer_type (value_enclosing_type (arg1)));
1501 /* ... and also the relative position of the subobject in the full
1502 object. */
1503 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1504 return arg2;
1505 }
1506
1507 /* Return a reference value for the object for which ARG1 is the
1508 contents. */
1509
1510 struct value *
1511 value_ref (struct value *arg1)
1512 {
1513 struct value *arg2;
1514 struct type *type = check_typedef (value_type (arg1));
1515
1516 if (TYPE_CODE (type) == TYPE_CODE_REF)
1517 return arg1;
1518
1519 arg2 = value_addr (arg1);
1520 deprecated_set_value_type (arg2, lookup_reference_type (type));
1521 return arg2;
1522 }
1523
1524 /* Given a value of a pointer type, apply the C unary * operator to
1525 it. */
1526
1527 struct value *
1528 value_ind (struct value *arg1)
1529 {
1530 struct type *base_type;
1531 struct value *arg2;
1532
1533 arg1 = coerce_array (arg1);
1534
1535 base_type = check_typedef (value_type (arg1));
1536
1537 if (VALUE_LVAL (arg1) == lval_computed)
1538 {
1539 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1540
1541 if (funcs->indirect)
1542 {
1543 struct value *result = funcs->indirect (arg1);
1544
1545 if (result)
1546 return result;
1547 }
1548 }
1549
1550 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1551 {
1552 struct type *enc_type;
1553
1554 /* We may be pointing to something embedded in a larger object.
1555 Get the real type of the enclosing object. */
1556 enc_type = check_typedef (value_enclosing_type (arg1));
1557 enc_type = TYPE_TARGET_TYPE (enc_type);
1558
1559 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1560 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1561 /* For functions, go through find_function_addr, which knows
1562 how to handle function descriptors. */
1563 arg2 = value_at_lazy (enc_type,
1564 find_function_addr (arg1, NULL));
1565 else
1566 /* Retrieve the enclosing object pointed to. */
1567 arg2 = value_at_lazy (enc_type,
1568 (value_as_address (arg1)
1569 - value_pointed_to_offset (arg1)));
1570
1571 enc_type = value_type (arg2);
1572 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1573 }
1574
1575 error (_("Attempt to take contents of a non-pointer value."));
1576 return 0; /* For lint -- never reached. */
1577 }
1578 \f
1579 /* Create a value for an array by allocating space in GDB, copying the
1580 data into that space, and then setting up an array value.
1581
1582 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1583 is populated from the values passed in ELEMVEC.
1584
1585 The element type of the array is inherited from the type of the
1586 first element, and all elements must have the same size (though we
1587 don't currently enforce any restriction on their types). */
1588
1589 struct value *
1590 value_array (int lowbound, int highbound, struct value **elemvec)
1591 {
1592 int nelem;
1593 int idx;
1594 unsigned int typelength;
1595 struct value *val;
1596 struct type *arraytype;
1597
1598 /* Validate that the bounds are reasonable and that each of the
1599 elements have the same size. */
1600
1601 nelem = highbound - lowbound + 1;
1602 if (nelem <= 0)
1603 {
1604 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1605 }
1606 typelength = type_length_units (value_enclosing_type (elemvec[0]));
1607 for (idx = 1; idx < nelem; idx++)
1608 {
1609 if (type_length_units (value_enclosing_type (elemvec[idx]))
1610 != typelength)
1611 {
1612 error (_("array elements must all be the same size"));
1613 }
1614 }
1615
1616 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1617 lowbound, highbound);
1618
1619 if (!current_language->c_style_arrays)
1620 {
1621 val = allocate_value (arraytype);
1622 for (idx = 0; idx < nelem; idx++)
1623 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1624 typelength);
1625 return val;
1626 }
1627
1628 /* Allocate space to store the array, and then initialize it by
1629 copying in each element. */
1630
1631 val = allocate_value (arraytype);
1632 for (idx = 0; idx < nelem; idx++)
1633 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1634 return val;
1635 }
1636
1637 struct value *
1638 value_cstring (const char *ptr, ssize_t len, struct type *char_type)
1639 {
1640 struct value *val;
1641 int lowbound = current_language->string_lower_bound;
1642 ssize_t highbound = len / TYPE_LENGTH (char_type);
1643 struct type *stringtype
1644 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1645
1646 val = allocate_value (stringtype);
1647 memcpy (value_contents_raw (val), ptr, len);
1648 return val;
1649 }
1650
1651 /* Create a value for a string constant by allocating space in the
1652 inferior, copying the data into that space, and returning the
1653 address with type TYPE_CODE_STRING. PTR points to the string
1654 constant data; LEN is number of characters.
1655
1656 Note that string types are like array of char types with a lower
1657 bound of zero and an upper bound of LEN - 1. Also note that the
1658 string may contain embedded null bytes. */
1659
1660 struct value *
1661 value_string (const char *ptr, ssize_t len, struct type *char_type)
1662 {
1663 struct value *val;
1664 int lowbound = current_language->string_lower_bound;
1665 ssize_t highbound = len / TYPE_LENGTH (char_type);
1666 struct type *stringtype
1667 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1668
1669 val = allocate_value (stringtype);
1670 memcpy (value_contents_raw (val), ptr, len);
1671 return val;
1672 }
1673
1674 \f
1675 /* See if we can pass arguments in T2 to a function which takes
1676 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1677 a NULL-terminated vector. If some arguments need coercion of some
1678 sort, then the coerced values are written into T2. Return value is
1679 0 if the arguments could be matched, or the position at which they
1680 differ if not.
1681
1682 STATICP is nonzero if the T1 argument list came from a static
1683 member function. T2 will still include the ``this'' pointer, but
1684 it will be skipped.
1685
1686 For non-static member functions, we ignore the first argument,
1687 which is the type of the instance variable. This is because we
1688 want to handle calls with objects from derived classes. This is
1689 not entirely correct: we should actually check to make sure that a
1690 requested operation is type secure, shouldn't we? FIXME. */
1691
1692 static int
1693 typecmp (int staticp, int varargs, int nargs,
1694 struct field t1[], struct value *t2[])
1695 {
1696 int i;
1697
1698 if (t2 == 0)
1699 internal_error (__FILE__, __LINE__,
1700 _("typecmp: no argument list"));
1701
1702 /* Skip ``this'' argument if applicable. T2 will always include
1703 THIS. */
1704 if (staticp)
1705 t2 ++;
1706
1707 for (i = 0;
1708 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1709 i++)
1710 {
1711 struct type *tt1, *tt2;
1712
1713 if (!t2[i])
1714 return i + 1;
1715
1716 tt1 = check_typedef (t1[i].type);
1717 tt2 = check_typedef (value_type (t2[i]));
1718
1719 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1720 /* We should be doing hairy argument matching, as below. */
1721 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1722 == TYPE_CODE (tt2)))
1723 {
1724 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1725 t2[i] = value_coerce_array (t2[i]);
1726 else
1727 t2[i] = value_ref (t2[i]);
1728 continue;
1729 }
1730
1731 /* djb - 20000715 - Until the new type structure is in the
1732 place, and we can attempt things like implicit conversions,
1733 we need to do this so you can take something like a map<const
1734 char *>, and properly access map["hello"], because the
1735 argument to [] will be a reference to a pointer to a char,
1736 and the argument will be a pointer to a char. */
1737 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1738 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1739 {
1740 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1741 }
1742 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1743 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1744 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1745 {
1746 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1747 }
1748 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1749 continue;
1750 /* Array to pointer is a `trivial conversion' according to the
1751 ARM. */
1752
1753 /* We should be doing much hairier argument matching (see
1754 section 13.2 of the ARM), but as a quick kludge, just check
1755 for the same type code. */
1756 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1757 return i + 1;
1758 }
1759 if (varargs || t2[i] == NULL)
1760 return 0;
1761 return i + 1;
1762 }
1763
1764 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1765 and *LAST_BOFFSET, and possibly throws an exception if the field
1766 search has yielded ambiguous results. */
1767
1768 static void
1769 update_search_result (struct value **result_ptr, struct value *v,
1770 int *last_boffset, int boffset,
1771 const char *name, struct type *type)
1772 {
1773 if (v != NULL)
1774 {
1775 if (*result_ptr != NULL
1776 /* The result is not ambiguous if all the classes that are
1777 found occupy the same space. */
1778 && *last_boffset != boffset)
1779 error (_("base class '%s' is ambiguous in type '%s'"),
1780 name, TYPE_SAFE_NAME (type));
1781 *result_ptr = v;
1782 *last_boffset = boffset;
1783 }
1784 }
1785
1786 /* A helper for search_struct_field. This does all the work; most
1787 arguments are as passed to search_struct_field. The result is
1788 stored in *RESULT_PTR, which must be initialized to NULL.
1789 OUTERMOST_TYPE is the type of the initial type passed to
1790 search_struct_field; this is used for error reporting when the
1791 lookup is ambiguous. */
1792
1793 static void
1794 do_search_struct_field (const char *name, struct value *arg1, int offset,
1795 struct type *type, int looking_for_baseclass,
1796 struct value **result_ptr,
1797 int *last_boffset,
1798 struct type *outermost_type)
1799 {
1800 int i;
1801 int nbases;
1802
1803 type = check_typedef (type);
1804 nbases = TYPE_N_BASECLASSES (type);
1805
1806 if (!looking_for_baseclass)
1807 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1808 {
1809 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1810
1811 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1812 {
1813 struct value *v;
1814
1815 if (field_is_static (&TYPE_FIELD (type, i)))
1816 v = value_static_field (type, i);
1817 else
1818 v = value_primitive_field (arg1, offset, i, type);
1819 *result_ptr = v;
1820 return;
1821 }
1822
1823 if (t_field_name
1824 && t_field_name[0] == '\0')
1825 {
1826 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1827
1828 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1829 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1830 {
1831 /* Look for a match through the fields of an anonymous
1832 union, or anonymous struct. C++ provides anonymous
1833 unions.
1834
1835 In the GNU Chill (now deleted from GDB)
1836 implementation of variant record types, each
1837 <alternative field> has an (anonymous) union type,
1838 each member of the union represents a <variant
1839 alternative>. Each <variant alternative> is
1840 represented as a struct, with a member for each
1841 <variant field>. */
1842
1843 struct value *v = NULL;
1844 int new_offset = offset;
1845
1846 /* This is pretty gross. In G++, the offset in an
1847 anonymous union is relative to the beginning of the
1848 enclosing struct. In the GNU Chill (now deleted
1849 from GDB) implementation of variant records, the
1850 bitpos is zero in an anonymous union field, so we
1851 have to add the offset of the union here. */
1852 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1853 || (TYPE_NFIELDS (field_type) > 0
1854 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1855 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1856
1857 do_search_struct_field (name, arg1, new_offset,
1858 field_type,
1859 looking_for_baseclass, &v,
1860 last_boffset,
1861 outermost_type);
1862 if (v)
1863 {
1864 *result_ptr = v;
1865 return;
1866 }
1867 }
1868 }
1869 }
1870
1871 for (i = 0; i < nbases; i++)
1872 {
1873 struct value *v = NULL;
1874 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1875 /* If we are looking for baseclasses, this is what we get when
1876 we hit them. But it could happen that the base part's member
1877 name is not yet filled in. */
1878 int found_baseclass = (looking_for_baseclass
1879 && TYPE_BASECLASS_NAME (type, i) != NULL
1880 && (strcmp_iw (name,
1881 TYPE_BASECLASS_NAME (type,
1882 i)) == 0));
1883 int boffset = value_embedded_offset (arg1) + offset;
1884
1885 if (BASETYPE_VIA_VIRTUAL (type, i))
1886 {
1887 struct value *v2;
1888
1889 boffset = baseclass_offset (type, i,
1890 value_contents_for_printing (arg1),
1891 value_embedded_offset (arg1) + offset,
1892 value_address (arg1),
1893 arg1);
1894
1895 /* The virtual base class pointer might have been clobbered
1896 by the user program. Make sure that it still points to a
1897 valid memory location. */
1898
1899 boffset += value_embedded_offset (arg1) + offset;
1900 if (boffset < 0
1901 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1902 {
1903 CORE_ADDR base_addr;
1904
1905 base_addr = value_address (arg1) + boffset;
1906 v2 = value_at_lazy (basetype, base_addr);
1907 if (target_read_memory (base_addr,
1908 value_contents_raw (v2),
1909 TYPE_LENGTH (value_type (v2))) != 0)
1910 error (_("virtual baseclass botch"));
1911 }
1912 else
1913 {
1914 v2 = value_copy (arg1);
1915 deprecated_set_value_type (v2, basetype);
1916 set_value_embedded_offset (v2, boffset);
1917 }
1918
1919 if (found_baseclass)
1920 v = v2;
1921 else
1922 {
1923 do_search_struct_field (name, v2, 0,
1924 TYPE_BASECLASS (type, i),
1925 looking_for_baseclass,
1926 result_ptr, last_boffset,
1927 outermost_type);
1928 }
1929 }
1930 else if (found_baseclass)
1931 v = value_primitive_field (arg1, offset, i, type);
1932 else
1933 {
1934 do_search_struct_field (name, arg1,
1935 offset + TYPE_BASECLASS_BITPOS (type,
1936 i) / 8,
1937 basetype, looking_for_baseclass,
1938 result_ptr, last_boffset,
1939 outermost_type);
1940 }
1941
1942 update_search_result (result_ptr, v, last_boffset,
1943 boffset, name, outermost_type);
1944 }
1945 }
1946
1947 /* Helper function used by value_struct_elt to recurse through
1948 baseclasses. Look for a field NAME in ARG1. Search in it assuming
1949 it has (class) type TYPE. If found, return value, else return NULL.
1950
1951 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1952 fields, look for a baseclass named NAME. */
1953
1954 static struct value *
1955 search_struct_field (const char *name, struct value *arg1,
1956 struct type *type, int looking_for_baseclass)
1957 {
1958 struct value *result = NULL;
1959 int boffset = 0;
1960
1961 do_search_struct_field (name, arg1, 0, type, looking_for_baseclass,
1962 &result, &boffset, type);
1963 return result;
1964 }
1965
1966 /* Helper function used by value_struct_elt to recurse through
1967 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1968 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1969 TYPE.
1970
1971 If found, return value, else if name matched and args not return
1972 (value) -1, else return NULL. */
1973
1974 static struct value *
1975 search_struct_method (const char *name, struct value **arg1p,
1976 struct value **args, int offset,
1977 int *static_memfuncp, struct type *type)
1978 {
1979 int i;
1980 struct value *v;
1981 int name_matched = 0;
1982 char dem_opname[64];
1983
1984 type = check_typedef (type);
1985 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1986 {
1987 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1988
1989 /* FIXME! May need to check for ARM demangling here. */
1990 if (startswith (t_field_name, "__") ||
1991 startswith (t_field_name, "op") ||
1992 startswith (t_field_name, "type"))
1993 {
1994 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1995 t_field_name = dem_opname;
1996 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1997 t_field_name = dem_opname;
1998 }
1999 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2000 {
2001 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2002 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2003
2004 name_matched = 1;
2005 check_stub_method_group (type, i);
2006 if (j > 0 && args == 0)
2007 error (_("cannot resolve overloaded method "
2008 "`%s': no arguments supplied"), name);
2009 else if (j == 0 && args == 0)
2010 {
2011 v = value_fn_field (arg1p, f, j, type, offset);
2012 if (v != NULL)
2013 return v;
2014 }
2015 else
2016 while (j >= 0)
2017 {
2018 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2019 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2020 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2021 TYPE_FN_FIELD_ARGS (f, j), args))
2022 {
2023 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2024 return value_virtual_fn_field (arg1p, f, j,
2025 type, offset);
2026 if (TYPE_FN_FIELD_STATIC_P (f, j)
2027 && static_memfuncp)
2028 *static_memfuncp = 1;
2029 v = value_fn_field (arg1p, f, j, type, offset);
2030 if (v != NULL)
2031 return v;
2032 }
2033 j--;
2034 }
2035 }
2036 }
2037
2038 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2039 {
2040 int base_offset;
2041 int this_offset;
2042
2043 if (BASETYPE_VIA_VIRTUAL (type, i))
2044 {
2045 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2046 struct value *base_val;
2047 const gdb_byte *base_valaddr;
2048
2049 /* The virtual base class pointer might have been
2050 clobbered by the user program. Make sure that it
2051 still points to a valid memory location. */
2052
2053 if (offset < 0 || offset >= TYPE_LENGTH (type))
2054 {
2055 gdb_byte *tmp;
2056 struct cleanup *back_to;
2057 CORE_ADDR address;
2058
2059 tmp = (gdb_byte *) xmalloc (TYPE_LENGTH (baseclass));
2060 back_to = make_cleanup (xfree, tmp);
2061 address = value_address (*arg1p);
2062
2063 if (target_read_memory (address + offset,
2064 tmp, TYPE_LENGTH (baseclass)) != 0)
2065 error (_("virtual baseclass botch"));
2066
2067 base_val = value_from_contents_and_address (baseclass,
2068 tmp,
2069 address + offset);
2070 base_valaddr = value_contents_for_printing (base_val);
2071 this_offset = 0;
2072 do_cleanups (back_to);
2073 }
2074 else
2075 {
2076 base_val = *arg1p;
2077 base_valaddr = value_contents_for_printing (*arg1p);
2078 this_offset = offset;
2079 }
2080
2081 base_offset = baseclass_offset (type, i, base_valaddr,
2082 this_offset, value_address (base_val),
2083 base_val);
2084 }
2085 else
2086 {
2087 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2088 }
2089 v = search_struct_method (name, arg1p, args, base_offset + offset,
2090 static_memfuncp, TYPE_BASECLASS (type, i));
2091 if (v == (struct value *) - 1)
2092 {
2093 name_matched = 1;
2094 }
2095 else if (v)
2096 {
2097 /* FIXME-bothner: Why is this commented out? Why is it here? */
2098 /* *arg1p = arg1_tmp; */
2099 return v;
2100 }
2101 }
2102 if (name_matched)
2103 return (struct value *) - 1;
2104 else
2105 return NULL;
2106 }
2107
2108 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2109 extract the component named NAME from the ultimate target
2110 structure/union and return it as a value with its appropriate type.
2111 ERR is used in the error message if *ARGP's type is wrong.
2112
2113 C++: ARGS is a list of argument types to aid in the selection of
2114 an appropriate method. Also, handle derived types.
2115
2116 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2117 where the truthvalue of whether the function that was resolved was
2118 a static member function or not is stored.
2119
2120 ERR is an error message to be printed in case the field is not
2121 found. */
2122
2123 struct value *
2124 value_struct_elt (struct value **argp, struct value **args,
2125 const char *name, int *static_memfuncp, const char *err)
2126 {
2127 struct type *t;
2128 struct value *v;
2129
2130 *argp = coerce_array (*argp);
2131
2132 t = check_typedef (value_type (*argp));
2133
2134 /* Follow pointers until we get to a non-pointer. */
2135
2136 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2137 {
2138 *argp = value_ind (*argp);
2139 /* Don't coerce fn pointer to fn and then back again! */
2140 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2141 *argp = coerce_array (*argp);
2142 t = check_typedef (value_type (*argp));
2143 }
2144
2145 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2146 && TYPE_CODE (t) != TYPE_CODE_UNION)
2147 error (_("Attempt to extract a component of a value that is not a %s."),
2148 err);
2149
2150 /* Assume it's not, unless we see that it is. */
2151 if (static_memfuncp)
2152 *static_memfuncp = 0;
2153
2154 if (!args)
2155 {
2156 /* if there are no arguments ...do this... */
2157
2158 /* Try as a field first, because if we succeed, there is less
2159 work to be done. */
2160 v = search_struct_field (name, *argp, t, 0);
2161 if (v)
2162 return v;
2163
2164 /* C++: If it was not found as a data field, then try to
2165 return it as a pointer to a method. */
2166 v = search_struct_method (name, argp, args, 0,
2167 static_memfuncp, t);
2168
2169 if (v == (struct value *) - 1)
2170 error (_("Cannot take address of method %s."), name);
2171 else if (v == 0)
2172 {
2173 if (TYPE_NFN_FIELDS (t))
2174 error (_("There is no member or method named %s."), name);
2175 else
2176 error (_("There is no member named %s."), name);
2177 }
2178 return v;
2179 }
2180
2181 v = search_struct_method (name, argp, args, 0,
2182 static_memfuncp, t);
2183
2184 if (v == (struct value *) - 1)
2185 {
2186 error (_("One of the arguments you tried to pass to %s could not "
2187 "be converted to what the function wants."), name);
2188 }
2189 else if (v == 0)
2190 {
2191 /* See if user tried to invoke data as function. If so, hand it
2192 back. If it's not callable (i.e., a pointer to function),
2193 gdb should give an error. */
2194 v = search_struct_field (name, *argp, t, 0);
2195 /* If we found an ordinary field, then it is not a method call.
2196 So, treat it as if it were a static member function. */
2197 if (v && static_memfuncp)
2198 *static_memfuncp = 1;
2199 }
2200
2201 if (!v)
2202 throw_error (NOT_FOUND_ERROR,
2203 _("Structure has no component named %s."), name);
2204 return v;
2205 }
2206
2207 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2208 to a structure or union, extract and return its component (field) of
2209 type FTYPE at the specified BITPOS.
2210 Throw an exception on error. */
2211
2212 struct value *
2213 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2214 const char *err)
2215 {
2216 struct type *t;
2217 struct value *v;
2218 int i;
2219 int nbases;
2220
2221 *argp = coerce_array (*argp);
2222
2223 t = check_typedef (value_type (*argp));
2224
2225 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2226 {
2227 *argp = value_ind (*argp);
2228 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2229 *argp = coerce_array (*argp);
2230 t = check_typedef (value_type (*argp));
2231 }
2232
2233 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2234 && TYPE_CODE (t) != TYPE_CODE_UNION)
2235 error (_("Attempt to extract a component of a value that is not a %s."),
2236 err);
2237
2238 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2239 {
2240 if (!field_is_static (&TYPE_FIELD (t, i))
2241 && bitpos == TYPE_FIELD_BITPOS (t, i)
2242 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2243 return value_primitive_field (*argp, 0, i, t);
2244 }
2245
2246 error (_("No field with matching bitpos and type."));
2247
2248 /* Never hit. */
2249 return NULL;
2250 }
2251
2252 /* Search through the methods of an object (and its bases) to find a
2253 specified method. Return the pointer to the fn_field list FN_LIST of
2254 overloaded instances defined in the source language. If available
2255 and matching, a vector of matching xmethods defined in extension
2256 languages are also returned in XM_WORKER_VEC
2257
2258 Helper function for value_find_oload_list.
2259 ARGP is a pointer to a pointer to a value (the object).
2260 METHOD is a string containing the method name.
2261 OFFSET is the offset within the value.
2262 TYPE is the assumed type of the object.
2263 FN_LIST is the pointer to matching overloaded instances defined in
2264 source language. Since this is a recursive function, *FN_LIST
2265 should be set to NULL when calling this function.
2266 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2267 0 when calling this function.
2268 XM_WORKER_VEC is the vector of matching xmethod workers. *XM_WORKER_VEC
2269 should also be set to NULL when calling this function.
2270 BASETYPE is set to the actual type of the subobject where the
2271 method is found.
2272 BOFFSET is the offset of the base subobject where the method is found. */
2273
2274 static void
2275 find_method_list (struct value **argp, const char *method,
2276 int offset, struct type *type,
2277 struct fn_field **fn_list, int *num_fns,
2278 VEC (xmethod_worker_ptr) **xm_worker_vec,
2279 struct type **basetype, int *boffset)
2280 {
2281 int i;
2282 struct fn_field *f = NULL;
2283 VEC (xmethod_worker_ptr) *worker_vec = NULL, *new_vec = NULL;
2284
2285 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2286 type = check_typedef (type);
2287
2288 /* First check in object itself.
2289 This function is called recursively to search through base classes.
2290 If there is a source method match found at some stage, then we need not
2291 look for source methods in consequent recursive calls. */
2292 if ((*fn_list) == NULL)
2293 {
2294 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2295 {
2296 /* pai: FIXME What about operators and type conversions? */
2297 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2298
2299 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2300 {
2301 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2302 f = TYPE_FN_FIELDLIST1 (type, i);
2303 *fn_list = f;
2304
2305 *num_fns = len;
2306 *basetype = type;
2307 *boffset = offset;
2308
2309 /* Resolve any stub methods. */
2310 check_stub_method_group (type, i);
2311
2312 break;
2313 }
2314 }
2315 }
2316
2317 /* Unlike source methods, xmethods can be accumulated over successive
2318 recursive calls. In other words, an xmethod named 'm' in a class
2319 will not hide an xmethod named 'm' in its base class(es). We want
2320 it to be this way because xmethods are after all convenience functions
2321 and hence there is no point restricting them with something like method
2322 hiding. Moreover, if hiding is done for xmethods as well, then we will
2323 have to provide a mechanism to un-hide (like the 'using' construct). */
2324 worker_vec = get_matching_xmethod_workers (type, method);
2325 new_vec = VEC_merge (xmethod_worker_ptr, *xm_worker_vec, worker_vec);
2326
2327 VEC_free (xmethod_worker_ptr, *xm_worker_vec);
2328 VEC_free (xmethod_worker_ptr, worker_vec);
2329 *xm_worker_vec = new_vec;
2330
2331 /* If source methods are not found in current class, look for them in the
2332 base classes. We also have to go through the base classes to gather
2333 extension methods. */
2334 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2335 {
2336 int base_offset;
2337
2338 if (BASETYPE_VIA_VIRTUAL (type, i))
2339 {
2340 base_offset = baseclass_offset (type, i,
2341 value_contents_for_printing (*argp),
2342 value_offset (*argp) + offset,
2343 value_address (*argp), *argp);
2344 }
2345 else /* Non-virtual base, simply use bit position from debug
2346 info. */
2347 {
2348 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2349 }
2350
2351 find_method_list (argp, method, base_offset + offset,
2352 TYPE_BASECLASS (type, i), fn_list, num_fns,
2353 xm_worker_vec, basetype, boffset);
2354 }
2355 }
2356
2357 /* Return the list of overloaded methods of a specified name. The methods
2358 could be those GDB finds in the binary, or xmethod. Methods found in
2359 the binary are returned in FN_LIST, and xmethods are returned in
2360 XM_WORKER_VEC.
2361
2362 ARGP is a pointer to a pointer to a value (the object).
2363 METHOD is the method name.
2364 OFFSET is the offset within the value contents.
2365 FN_LIST is the pointer to matching overloaded instances defined in
2366 source language.
2367 NUM_FNS is the number of overloaded instances.
2368 XM_WORKER_VEC is the vector of matching xmethod workers defined in
2369 extension languages.
2370 BASETYPE is set to the type of the base subobject that defines the
2371 method.
2372 BOFFSET is the offset of the base subobject which defines the method. */
2373
2374 static void
2375 value_find_oload_method_list (struct value **argp, const char *method,
2376 int offset, struct fn_field **fn_list,
2377 int *num_fns,
2378 VEC (xmethod_worker_ptr) **xm_worker_vec,
2379 struct type **basetype, int *boffset)
2380 {
2381 struct type *t;
2382
2383 t = check_typedef (value_type (*argp));
2384
2385 /* Code snarfed from value_struct_elt. */
2386 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2387 {
2388 *argp = value_ind (*argp);
2389 /* Don't coerce fn pointer to fn and then back again! */
2390 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2391 *argp = coerce_array (*argp);
2392 t = check_typedef (value_type (*argp));
2393 }
2394
2395 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2396 && TYPE_CODE (t) != TYPE_CODE_UNION)
2397 error (_("Attempt to extract a component of a "
2398 "value that is not a struct or union"));
2399
2400 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2401
2402 /* Clear the lists. */
2403 *fn_list = NULL;
2404 *num_fns = 0;
2405 *xm_worker_vec = NULL;
2406
2407 find_method_list (argp, method, 0, t, fn_list, num_fns, xm_worker_vec,
2408 basetype, boffset);
2409 }
2410
2411 /* Given an array of arguments (ARGS) (which includes an
2412 entry for "this" in the case of C++ methods), the number of
2413 arguments NARGS, the NAME of a function, and whether it's a method or
2414 not (METHOD), find the best function that matches on the argument types
2415 according to the overload resolution rules.
2416
2417 METHOD can be one of three values:
2418 NON_METHOD for non-member functions.
2419 METHOD: for member functions.
2420 BOTH: used for overload resolution of operators where the
2421 candidates are expected to be either member or non member
2422 functions. In this case the first argument ARGTYPES
2423 (representing 'this') is expected to be a reference to the
2424 target object, and will be dereferenced when attempting the
2425 non-member search.
2426
2427 In the case of class methods, the parameter OBJ is an object value
2428 in which to search for overloaded methods.
2429
2430 In the case of non-method functions, the parameter FSYM is a symbol
2431 corresponding to one of the overloaded functions.
2432
2433 Return value is an integer: 0 -> good match, 10 -> debugger applied
2434 non-standard coercions, 100 -> incompatible.
2435
2436 If a method is being searched for, VALP will hold the value.
2437 If a non-method is being searched for, SYMP will hold the symbol
2438 for it.
2439
2440 If a method is being searched for, and it is a static method,
2441 then STATICP will point to a non-zero value.
2442
2443 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2444 ADL overload candidates when performing overload resolution for a fully
2445 qualified name.
2446
2447 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2448 read while picking the best overload match (it may be all zeroes and thus
2449 not have a vtable pointer), in which case skip virtual function lookup.
2450 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2451 the result type.
2452
2453 Note: This function does *not* check the value of
2454 overload_resolution. Caller must check it to see whether overload
2455 resolution is permitted. */
2456
2457 int
2458 find_overload_match (struct value **args, int nargs,
2459 const char *name, enum oload_search_type method,
2460 struct value **objp, struct symbol *fsym,
2461 struct value **valp, struct symbol **symp,
2462 int *staticp, const int no_adl,
2463 const enum noside noside)
2464 {
2465 struct value *obj = (objp ? *objp : NULL);
2466 struct type *obj_type = obj ? value_type (obj) : NULL;
2467 /* Index of best overloaded function. */
2468 int func_oload_champ = -1;
2469 int method_oload_champ = -1;
2470 int src_method_oload_champ = -1;
2471 int ext_method_oload_champ = -1;
2472 int src_and_ext_equal = 0;
2473
2474 /* The measure for the current best match. */
2475 struct badness_vector *method_badness = NULL;
2476 struct badness_vector *func_badness = NULL;
2477 struct badness_vector *ext_method_badness = NULL;
2478 struct badness_vector *src_method_badness = NULL;
2479
2480 struct value *temp = obj;
2481 /* For methods, the list of overloaded methods. */
2482 struct fn_field *fns_ptr = NULL;
2483 /* For non-methods, the list of overloaded function symbols. */
2484 struct symbol **oload_syms = NULL;
2485 /* For xmethods, the VEC of xmethod workers. */
2486 VEC (xmethod_worker_ptr) *xm_worker_vec = NULL;
2487 /* Number of overloaded instances being considered. */
2488 int num_fns = 0;
2489 struct type *basetype = NULL;
2490 int boffset;
2491
2492 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2493
2494 const char *obj_type_name = NULL;
2495 const char *func_name = NULL;
2496 enum oload_classification match_quality;
2497 enum oload_classification method_match_quality = INCOMPATIBLE;
2498 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2499 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2500 enum oload_classification func_match_quality = INCOMPATIBLE;
2501
2502 /* Get the list of overloaded methods or functions. */
2503 if (method == METHOD || method == BOTH)
2504 {
2505 gdb_assert (obj);
2506
2507 /* OBJ may be a pointer value rather than the object itself. */
2508 obj = coerce_ref (obj);
2509 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2510 obj = coerce_ref (value_ind (obj));
2511 obj_type_name = TYPE_NAME (value_type (obj));
2512
2513 /* First check whether this is a data member, e.g. a pointer to
2514 a function. */
2515 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2516 {
2517 *valp = search_struct_field (name, obj,
2518 check_typedef (value_type (obj)), 0);
2519 if (*valp)
2520 {
2521 *staticp = 1;
2522 do_cleanups (all_cleanups);
2523 return 0;
2524 }
2525 }
2526
2527 /* Retrieve the list of methods with the name NAME. */
2528 value_find_oload_method_list (&temp, name, 0, &fns_ptr, &num_fns,
2529 &xm_worker_vec, &basetype, &boffset);
2530 /* If this is a method only search, and no methods were found
2531 the search has faild. */
2532 if (method == METHOD && (!fns_ptr || !num_fns) && !xm_worker_vec)
2533 error (_("Couldn't find method %s%s%s"),
2534 obj_type_name,
2535 (obj_type_name && *obj_type_name) ? "::" : "",
2536 name);
2537 /* If we are dealing with stub method types, they should have
2538 been resolved by find_method_list via
2539 value_find_oload_method_list above. */
2540 if (fns_ptr)
2541 {
2542 gdb_assert (TYPE_SELF_TYPE (fns_ptr[0].type) != NULL);
2543
2544 src_method_oload_champ = find_oload_champ (args, nargs,
2545 num_fns, fns_ptr, NULL,
2546 NULL, &src_method_badness);
2547
2548 src_method_match_quality = classify_oload_match
2549 (src_method_badness, nargs,
2550 oload_method_static_p (fns_ptr, src_method_oload_champ));
2551
2552 make_cleanup (xfree, src_method_badness);
2553 }
2554
2555 if (VEC_length (xmethod_worker_ptr, xm_worker_vec) > 0)
2556 {
2557 ext_method_oload_champ = find_oload_champ (args, nargs,
2558 0, NULL, xm_worker_vec,
2559 NULL, &ext_method_badness);
2560 ext_method_match_quality = classify_oload_match (ext_method_badness,
2561 nargs, 0);
2562 make_cleanup (xfree, ext_method_badness);
2563 make_cleanup (free_xmethod_worker_vec, xm_worker_vec);
2564 }
2565
2566 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2567 {
2568 switch (compare_badness (ext_method_badness, src_method_badness))
2569 {
2570 case 0: /* Src method and xmethod are equally good. */
2571 src_and_ext_equal = 1;
2572 /* If src method and xmethod are equally good, then
2573 xmethod should be the winner. Hence, fall through to the
2574 case where a xmethod is better than the source
2575 method, except when the xmethod match quality is
2576 non-standard. */
2577 /* FALLTHROUGH */
2578 case 1: /* Src method and ext method are incompatible. */
2579 /* If ext method match is not standard, then let source method
2580 win. Otherwise, fallthrough to let xmethod win. */
2581 if (ext_method_match_quality != STANDARD)
2582 {
2583 method_oload_champ = src_method_oload_champ;
2584 method_badness = src_method_badness;
2585 ext_method_oload_champ = -1;
2586 method_match_quality = src_method_match_quality;
2587 break;
2588 }
2589 /* FALLTHROUGH */
2590 case 2: /* Ext method is champion. */
2591 method_oload_champ = ext_method_oload_champ;
2592 method_badness = ext_method_badness;
2593 src_method_oload_champ = -1;
2594 method_match_quality = ext_method_match_quality;
2595 break;
2596 case 3: /* Src method is champion. */
2597 method_oload_champ = src_method_oload_champ;
2598 method_badness = src_method_badness;
2599 ext_method_oload_champ = -1;
2600 method_match_quality = src_method_match_quality;
2601 break;
2602 default:
2603 gdb_assert_not_reached ("Unexpected overload comparison "
2604 "result");
2605 break;
2606 }
2607 }
2608 else if (src_method_oload_champ >= 0)
2609 {
2610 method_oload_champ = src_method_oload_champ;
2611 method_badness = src_method_badness;
2612 method_match_quality = src_method_match_quality;
2613 }
2614 else if (ext_method_oload_champ >= 0)
2615 {
2616 method_oload_champ = ext_method_oload_champ;
2617 method_badness = ext_method_badness;
2618 method_match_quality = ext_method_match_quality;
2619 }
2620 }
2621
2622 if (method == NON_METHOD || method == BOTH)
2623 {
2624 const char *qualified_name = NULL;
2625
2626 /* If the overload match is being search for both as a method
2627 and non member function, the first argument must now be
2628 dereferenced. */
2629 if (method == BOTH)
2630 args[0] = value_ind (args[0]);
2631
2632 if (fsym)
2633 {
2634 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2635
2636 /* If we have a function with a C++ name, try to extract just
2637 the function part. Do not try this for non-functions (e.g.
2638 function pointers). */
2639 if (qualified_name
2640 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2641 == TYPE_CODE_FUNC)
2642 {
2643 char *temp;
2644
2645 temp = cp_func_name (qualified_name);
2646
2647 /* If cp_func_name did not remove anything, the name of the
2648 symbol did not include scope or argument types - it was
2649 probably a C-style function. */
2650 if (temp)
2651 {
2652 make_cleanup (xfree, temp);
2653 if (strcmp (temp, qualified_name) == 0)
2654 func_name = NULL;
2655 else
2656 func_name = temp;
2657 }
2658 }
2659 }
2660 else
2661 {
2662 func_name = name;
2663 qualified_name = name;
2664 }
2665
2666 /* If there was no C++ name, this must be a C-style function or
2667 not a function at all. Just return the same symbol. Do the
2668 same if cp_func_name fails for some reason. */
2669 if (func_name == NULL)
2670 {
2671 *symp = fsym;
2672 do_cleanups (all_cleanups);
2673 return 0;
2674 }
2675
2676 func_oload_champ = find_oload_champ_namespace (args, nargs,
2677 func_name,
2678 qualified_name,
2679 &oload_syms,
2680 &func_badness,
2681 no_adl);
2682
2683 if (func_oload_champ >= 0)
2684 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2685
2686 make_cleanup (xfree, oload_syms);
2687 make_cleanup (xfree, func_badness);
2688 }
2689
2690 /* Did we find a match ? */
2691 if (method_oload_champ == -1 && func_oload_champ == -1)
2692 throw_error (NOT_FOUND_ERROR,
2693 _("No symbol \"%s\" in current context."),
2694 name);
2695
2696 /* If we have found both a method match and a function
2697 match, find out which one is better, and calculate match
2698 quality. */
2699 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2700 {
2701 switch (compare_badness (func_badness, method_badness))
2702 {
2703 case 0: /* Top two contenders are equally good. */
2704 /* FIXME: GDB does not support the general ambiguous case.
2705 All candidates should be collected and presented the
2706 user. */
2707 error (_("Ambiguous overload resolution"));
2708 break;
2709 case 1: /* Incomparable top contenders. */
2710 /* This is an error incompatible candidates
2711 should not have been proposed. */
2712 error (_("Internal error: incompatible "
2713 "overload candidates proposed"));
2714 break;
2715 case 2: /* Function champion. */
2716 method_oload_champ = -1;
2717 match_quality = func_match_quality;
2718 break;
2719 case 3: /* Method champion. */
2720 func_oload_champ = -1;
2721 match_quality = method_match_quality;
2722 break;
2723 default:
2724 error (_("Internal error: unexpected overload comparison result"));
2725 break;
2726 }
2727 }
2728 else
2729 {
2730 /* We have either a method match or a function match. */
2731 if (method_oload_champ >= 0)
2732 match_quality = method_match_quality;
2733 else
2734 match_quality = func_match_quality;
2735 }
2736
2737 if (match_quality == INCOMPATIBLE)
2738 {
2739 if (method == METHOD)
2740 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2741 obj_type_name,
2742 (obj_type_name && *obj_type_name) ? "::" : "",
2743 name);
2744 else
2745 error (_("Cannot resolve function %s to any overloaded instance"),
2746 func_name);
2747 }
2748 else if (match_quality == NON_STANDARD)
2749 {
2750 if (method == METHOD)
2751 warning (_("Using non-standard conversion to match "
2752 "method %s%s%s to supplied arguments"),
2753 obj_type_name,
2754 (obj_type_name && *obj_type_name) ? "::" : "",
2755 name);
2756 else
2757 warning (_("Using non-standard conversion to match "
2758 "function %s to supplied arguments"),
2759 func_name);
2760 }
2761
2762 if (staticp != NULL)
2763 *staticp = oload_method_static_p (fns_ptr, method_oload_champ);
2764
2765 if (method_oload_champ >= 0)
2766 {
2767 if (src_method_oload_champ >= 0)
2768 {
2769 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)
2770 && noside != EVAL_AVOID_SIDE_EFFECTS)
2771 {
2772 *valp = value_virtual_fn_field (&temp, fns_ptr,
2773 method_oload_champ, basetype,
2774 boffset);
2775 }
2776 else
2777 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2778 basetype, boffset);
2779 }
2780 else
2781 {
2782 *valp = value_of_xmethod (clone_xmethod_worker
2783 (VEC_index (xmethod_worker_ptr, xm_worker_vec,
2784 ext_method_oload_champ)));
2785 }
2786 }
2787 else
2788 *symp = oload_syms[func_oload_champ];
2789
2790 if (objp)
2791 {
2792 struct type *temp_type = check_typedef (value_type (temp));
2793 struct type *objtype = check_typedef (obj_type);
2794
2795 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2796 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2797 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2798 {
2799 temp = value_addr (temp);
2800 }
2801 *objp = temp;
2802 }
2803
2804 do_cleanups (all_cleanups);
2805
2806 switch (match_quality)
2807 {
2808 case INCOMPATIBLE:
2809 return 100;
2810 case NON_STANDARD:
2811 return 10;
2812 default: /* STANDARD */
2813 return 0;
2814 }
2815 }
2816
2817 /* Find the best overload match, searching for FUNC_NAME in namespaces
2818 contained in QUALIFIED_NAME until it either finds a good match or
2819 runs out of namespaces. It stores the overloaded functions in
2820 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2821 calling function is responsible for freeing *OLOAD_SYMS and
2822 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2823 performned. */
2824
2825 static int
2826 find_oload_champ_namespace (struct value **args, int nargs,
2827 const char *func_name,
2828 const char *qualified_name,
2829 struct symbol ***oload_syms,
2830 struct badness_vector **oload_champ_bv,
2831 const int no_adl)
2832 {
2833 int oload_champ;
2834
2835 find_oload_champ_namespace_loop (args, nargs,
2836 func_name,
2837 qualified_name, 0,
2838 oload_syms, oload_champ_bv,
2839 &oload_champ,
2840 no_adl);
2841
2842 return oload_champ;
2843 }
2844
2845 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2846 how deep we've looked for namespaces, and the champ is stored in
2847 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2848 if it isn't. Other arguments are the same as in
2849 find_oload_champ_namespace
2850
2851 It is the caller's responsibility to free *OLOAD_SYMS and
2852 *OLOAD_CHAMP_BV. */
2853
2854 static int
2855 find_oload_champ_namespace_loop (struct value **args, int nargs,
2856 const char *func_name,
2857 const char *qualified_name,
2858 int namespace_len,
2859 struct symbol ***oload_syms,
2860 struct badness_vector **oload_champ_bv,
2861 int *oload_champ,
2862 const int no_adl)
2863 {
2864 int next_namespace_len = namespace_len;
2865 int searched_deeper = 0;
2866 int num_fns = 0;
2867 struct cleanup *old_cleanups;
2868 int new_oload_champ;
2869 struct symbol **new_oload_syms;
2870 struct badness_vector *new_oload_champ_bv;
2871 char *new_namespace;
2872
2873 if (next_namespace_len != 0)
2874 {
2875 gdb_assert (qualified_name[next_namespace_len] == ':');
2876 next_namespace_len += 2;
2877 }
2878 next_namespace_len +=
2879 cp_find_first_component (qualified_name + next_namespace_len);
2880
2881 /* Initialize these to values that can safely be xfree'd. */
2882 *oload_syms = NULL;
2883 *oload_champ_bv = NULL;
2884
2885 /* First, see if we have a deeper namespace we can search in.
2886 If we get a good match there, use it. */
2887
2888 if (qualified_name[next_namespace_len] == ':')
2889 {
2890 searched_deeper = 1;
2891
2892 if (find_oload_champ_namespace_loop (args, nargs,
2893 func_name, qualified_name,
2894 next_namespace_len,
2895 oload_syms, oload_champ_bv,
2896 oload_champ, no_adl))
2897 {
2898 return 1;
2899 }
2900 };
2901
2902 /* If we reach here, either we're in the deepest namespace or we
2903 didn't find a good match in a deeper namespace. But, in the
2904 latter case, we still have a bad match in a deeper namespace;
2905 note that we might not find any match at all in the current
2906 namespace. (There's always a match in the deepest namespace,
2907 because this overload mechanism only gets called if there's a
2908 function symbol to start off with.) */
2909
2910 old_cleanups = make_cleanup (xfree, *oload_syms);
2911 make_cleanup (xfree, *oload_champ_bv);
2912 new_namespace = (char *) alloca (namespace_len + 1);
2913 strncpy (new_namespace, qualified_name, namespace_len);
2914 new_namespace[namespace_len] = '\0';
2915 new_oload_syms = make_symbol_overload_list (func_name,
2916 new_namespace);
2917
2918 /* If we have reached the deepest level perform argument
2919 determined lookup. */
2920 if (!searched_deeper && !no_adl)
2921 {
2922 int ix;
2923 struct type **arg_types;
2924
2925 /* Prepare list of argument types for overload resolution. */
2926 arg_types = (struct type **)
2927 alloca (nargs * (sizeof (struct type *)));
2928 for (ix = 0; ix < nargs; ix++)
2929 arg_types[ix] = value_type (args[ix]);
2930 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2931 }
2932
2933 while (new_oload_syms[num_fns])
2934 ++num_fns;
2935
2936 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2937 NULL, NULL, new_oload_syms,
2938 &new_oload_champ_bv);
2939
2940 /* Case 1: We found a good match. Free earlier matches (if any),
2941 and return it. Case 2: We didn't find a good match, but we're
2942 not the deepest function. Then go with the bad match that the
2943 deeper function found. Case 3: We found a bad match, and we're
2944 the deepest function. Then return what we found, even though
2945 it's a bad match. */
2946
2947 if (new_oload_champ != -1
2948 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2949 {
2950 *oload_syms = new_oload_syms;
2951 *oload_champ = new_oload_champ;
2952 *oload_champ_bv = new_oload_champ_bv;
2953 do_cleanups (old_cleanups);
2954 return 1;
2955 }
2956 else if (searched_deeper)
2957 {
2958 xfree (new_oload_syms);
2959 xfree (new_oload_champ_bv);
2960 discard_cleanups (old_cleanups);
2961 return 0;
2962 }
2963 else
2964 {
2965 *oload_syms = new_oload_syms;
2966 *oload_champ = new_oload_champ;
2967 *oload_champ_bv = new_oload_champ_bv;
2968 do_cleanups (old_cleanups);
2969 return 0;
2970 }
2971 }
2972
2973 /* Look for a function to take NARGS args of ARGS. Find
2974 the best match from among the overloaded methods or functions
2975 given by FNS_PTR or OLOAD_SYMS or XM_WORKER_VEC, respectively.
2976 One, and only one of FNS_PTR, OLOAD_SYMS and XM_WORKER_VEC can be
2977 non-NULL.
2978
2979 If XM_WORKER_VEC is NULL, then the length of the arrays FNS_PTR
2980 or OLOAD_SYMS (whichever is non-NULL) is specified in NUM_FNS.
2981
2982 Return the index of the best match; store an indication of the
2983 quality of the match in OLOAD_CHAMP_BV.
2984
2985 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2986
2987 static int
2988 find_oload_champ (struct value **args, int nargs,
2989 int num_fns, struct fn_field *fns_ptr,
2990 VEC (xmethod_worker_ptr) *xm_worker_vec,
2991 struct symbol **oload_syms,
2992 struct badness_vector **oload_champ_bv)
2993 {
2994 int ix;
2995 int fn_count;
2996 int xm_worker_vec_n = VEC_length (xmethod_worker_ptr, xm_worker_vec);
2997 /* A measure of how good an overloaded instance is. */
2998 struct badness_vector *bv;
2999 /* Index of best overloaded function. */
3000 int oload_champ = -1;
3001 /* Current ambiguity state for overload resolution. */
3002 int oload_ambiguous = 0;
3003 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
3004
3005 /* A champion can be found among methods alone, or among functions
3006 alone, or in xmethods alone, but not in more than one of these
3007 groups. */
3008 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) + (xm_worker_vec != NULL)
3009 == 1);
3010
3011 *oload_champ_bv = NULL;
3012
3013 fn_count = (xm_worker_vec != NULL
3014 ? VEC_length (xmethod_worker_ptr, xm_worker_vec)
3015 : num_fns);
3016 /* Consider each candidate in turn. */
3017 for (ix = 0; ix < fn_count; ix++)
3018 {
3019 int jj;
3020 int static_offset = 0;
3021 int nparms;
3022 struct type **parm_types;
3023 struct xmethod_worker *worker = NULL;
3024
3025 if (xm_worker_vec != NULL)
3026 {
3027 worker = VEC_index (xmethod_worker_ptr, xm_worker_vec, ix);
3028 parm_types = get_xmethod_arg_types (worker, &nparms);
3029 }
3030 else
3031 {
3032 if (fns_ptr != NULL)
3033 {
3034 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
3035 static_offset = oload_method_static_p (fns_ptr, ix);
3036 }
3037 else
3038 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
3039
3040 parm_types = XNEWVEC (struct type *, nparms);
3041 for (jj = 0; jj < nparms; jj++)
3042 parm_types[jj] = (fns_ptr != NULL
3043 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
3044 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
3045 jj));
3046 }
3047
3048 /* Compare parameter types to supplied argument types. Skip
3049 THIS for static methods. */
3050 bv = rank_function (parm_types, nparms,
3051 args + static_offset,
3052 nargs - static_offset);
3053
3054 if (!*oload_champ_bv)
3055 {
3056 *oload_champ_bv = bv;
3057 oload_champ = 0;
3058 }
3059 else /* See whether current candidate is better or worse than
3060 previous best. */
3061 switch (compare_badness (bv, *oload_champ_bv))
3062 {
3063 case 0: /* Top two contenders are equally good. */
3064 oload_ambiguous = 1;
3065 break;
3066 case 1: /* Incomparable top contenders. */
3067 oload_ambiguous = 2;
3068 break;
3069 case 2: /* New champion, record details. */
3070 *oload_champ_bv = bv;
3071 oload_ambiguous = 0;
3072 oload_champ = ix;
3073 break;
3074 case 3:
3075 default:
3076 break;
3077 }
3078 xfree (parm_types);
3079 if (overload_debug)
3080 {
3081 if (fns_ptr != NULL)
3082 fprintf_filtered (gdb_stderr,
3083 "Overloaded method instance %s, # of parms %d\n",
3084 fns_ptr[ix].physname, nparms);
3085 else if (xm_worker_vec != NULL)
3086 fprintf_filtered (gdb_stderr,
3087 "Xmethod worker, # of parms %d\n",
3088 nparms);
3089 else
3090 fprintf_filtered (gdb_stderr,
3091 "Overloaded function instance "
3092 "%s # of parms %d\n",
3093 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3094 nparms);
3095 for (jj = 0; jj < nargs - static_offset; jj++)
3096 fprintf_filtered (gdb_stderr,
3097 "...Badness @ %d : %d\n",
3098 jj, bv->rank[jj].rank);
3099 fprintf_filtered (gdb_stderr, "Overload resolution "
3100 "champion is %d, ambiguous? %d\n",
3101 oload_champ, oload_ambiguous);
3102 }
3103 }
3104
3105 return oload_champ;
3106 }
3107
3108 /* Return 1 if we're looking at a static method, 0 if we're looking at
3109 a non-static method or a function that isn't a method. */
3110
3111 static int
3112 oload_method_static_p (struct fn_field *fns_ptr, int index)
3113 {
3114 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3115 return 1;
3116 else
3117 return 0;
3118 }
3119
3120 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3121
3122 static enum oload_classification
3123 classify_oload_match (struct badness_vector *oload_champ_bv,
3124 int nargs,
3125 int static_offset)
3126 {
3127 int ix;
3128 enum oload_classification worst = STANDARD;
3129
3130 for (ix = 1; ix <= nargs - static_offset; ix++)
3131 {
3132 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3133 or worse return INCOMPATIBLE. */
3134 if (compare_ranks (oload_champ_bv->rank[ix],
3135 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3136 return INCOMPATIBLE; /* Truly mismatched types. */
3137 /* Otherwise If this conversion is as bad as
3138 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3139 else if (compare_ranks (oload_champ_bv->rank[ix],
3140 NS_POINTER_CONVERSION_BADNESS) <= 0)
3141 worst = NON_STANDARD; /* Non-standard type conversions
3142 needed. */
3143 }
3144
3145 /* If no INCOMPATIBLE classification was found, return the worst one
3146 that was found (if any). */
3147 return worst;
3148 }
3149
3150 /* C++: return 1 is NAME is a legitimate name for the destructor of
3151 type TYPE. If TYPE does not have a destructor, or if NAME is
3152 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3153 have CHECK_TYPEDEF applied, this function will apply it itself. */
3154
3155 int
3156 destructor_name_p (const char *name, struct type *type)
3157 {
3158 if (name[0] == '~')
3159 {
3160 const char *dname = type_name_no_tag_or_error (type);
3161 const char *cp = strchr (dname, '<');
3162 unsigned int len;
3163
3164 /* Do not compare the template part for template classes. */
3165 if (cp == NULL)
3166 len = strlen (dname);
3167 else
3168 len = cp - dname;
3169 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3170 error (_("name of destructor must equal name of class"));
3171 else
3172 return 1;
3173 }
3174 return 0;
3175 }
3176
3177 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3178 class". If the name is found, return a value representing it;
3179 otherwise throw an exception. */
3180
3181 static struct value *
3182 enum_constant_from_type (struct type *type, const char *name)
3183 {
3184 int i;
3185 int name_len = strlen (name);
3186
3187 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3188 && TYPE_DECLARED_CLASS (type));
3189
3190 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3191 {
3192 const char *fname = TYPE_FIELD_NAME (type, i);
3193 int len;
3194
3195 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3196 || fname == NULL)
3197 continue;
3198
3199 /* Look for the trailing "::NAME", since enum class constant
3200 names are qualified here. */
3201 len = strlen (fname);
3202 if (len + 2 >= name_len
3203 && fname[len - name_len - 2] == ':'
3204 && fname[len - name_len - 1] == ':'
3205 && strcmp (&fname[len - name_len], name) == 0)
3206 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3207 }
3208
3209 error (_("no constant named \"%s\" in enum \"%s\""),
3210 name, TYPE_TAG_NAME (type));
3211 }
3212
3213 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3214 return the appropriate member (or the address of the member, if
3215 WANT_ADDRESS). This function is used to resolve user expressions
3216 of the form "DOMAIN::NAME". For more details on what happens, see
3217 the comment before value_struct_elt_for_reference. */
3218
3219 struct value *
3220 value_aggregate_elt (struct type *curtype, const char *name,
3221 struct type *expect_type, int want_address,
3222 enum noside noside)
3223 {
3224 switch (TYPE_CODE (curtype))
3225 {
3226 case TYPE_CODE_STRUCT:
3227 case TYPE_CODE_UNION:
3228 return value_struct_elt_for_reference (curtype, 0, curtype,
3229 name, expect_type,
3230 want_address, noside);
3231 case TYPE_CODE_NAMESPACE:
3232 return value_namespace_elt (curtype, name,
3233 want_address, noside);
3234
3235 case TYPE_CODE_ENUM:
3236 return enum_constant_from_type (curtype, name);
3237
3238 default:
3239 internal_error (__FILE__, __LINE__,
3240 _("non-aggregate type in value_aggregate_elt"));
3241 }
3242 }
3243
3244 /* Compares the two method/function types T1 and T2 for "equality"
3245 with respect to the methods' parameters. If the types of the
3246 two parameter lists are the same, returns 1; 0 otherwise. This
3247 comparison may ignore any artificial parameters in T1 if
3248 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3249 the first artificial parameter in T1, assumed to be a 'this' pointer.
3250
3251 The type T2 is expected to have come from make_params (in eval.c). */
3252
3253 static int
3254 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3255 {
3256 int start = 0;
3257
3258 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3259 ++start;
3260
3261 /* If skipping artificial fields, find the first real field
3262 in T1. */
3263 if (skip_artificial)
3264 {
3265 while (start < TYPE_NFIELDS (t1)
3266 && TYPE_FIELD_ARTIFICIAL (t1, start))
3267 ++start;
3268 }
3269
3270 /* Now compare parameters. */
3271
3272 /* Special case: a method taking void. T1 will contain no
3273 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3274 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3275 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3276 return 1;
3277
3278 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3279 {
3280 int i;
3281
3282 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3283 {
3284 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3285 TYPE_FIELD_TYPE (t2, i), NULL),
3286 EXACT_MATCH_BADNESS) != 0)
3287 return 0;
3288 }
3289
3290 return 1;
3291 }
3292
3293 return 0;
3294 }
3295
3296 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3297 return the address of this member as a "pointer to member" type.
3298 If INTYPE is non-null, then it will be the type of the member we
3299 are looking for. This will help us resolve "pointers to member
3300 functions". This function is used to resolve user expressions of
3301 the form "DOMAIN::NAME". */
3302
3303 static struct value *
3304 value_struct_elt_for_reference (struct type *domain, int offset,
3305 struct type *curtype, const char *name,
3306 struct type *intype,
3307 int want_address,
3308 enum noside noside)
3309 {
3310 struct type *t = curtype;
3311 int i;
3312 struct value *v, *result;
3313
3314 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3315 && TYPE_CODE (t) != TYPE_CODE_UNION)
3316 error (_("Internal error: non-aggregate type "
3317 "to value_struct_elt_for_reference"));
3318
3319 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3320 {
3321 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3322
3323 if (t_field_name && strcmp (t_field_name, name) == 0)
3324 {
3325 if (field_is_static (&TYPE_FIELD (t, i)))
3326 {
3327 v = value_static_field (t, i);
3328 if (want_address)
3329 v = value_addr (v);
3330 return v;
3331 }
3332 if (TYPE_FIELD_PACKED (t, i))
3333 error (_("pointers to bitfield members not allowed"));
3334
3335 if (want_address)
3336 return value_from_longest
3337 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3338 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3339 else if (noside != EVAL_NORMAL)
3340 return allocate_value (TYPE_FIELD_TYPE (t, i));
3341 else
3342 {
3343 /* Try to evaluate NAME as a qualified name with implicit
3344 this pointer. In this case, attempt to return the
3345 equivalent to `this->*(&TYPE::NAME)'. */
3346 v = value_of_this_silent (current_language);
3347 if (v != NULL)
3348 {
3349 struct value *ptr;
3350 long mem_offset;
3351 struct type *type, *tmp;
3352
3353 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3354 type = check_typedef (value_type (ptr));
3355 gdb_assert (type != NULL
3356 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3357 tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
3358 v = value_cast_pointers (tmp, v, 1);
3359 mem_offset = value_as_long (ptr);
3360 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3361 result = value_from_pointer (tmp,
3362 value_as_long (v) + mem_offset);
3363 return value_ind (result);
3364 }
3365
3366 error (_("Cannot reference non-static field \"%s\""), name);
3367 }
3368 }
3369 }
3370
3371 /* C++: If it was not found as a data field, then try to return it
3372 as a pointer to a method. */
3373
3374 /* Perform all necessary dereferencing. */
3375 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3376 intype = TYPE_TARGET_TYPE (intype);
3377
3378 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3379 {
3380 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3381 char dem_opname[64];
3382
3383 if (startswith (t_field_name, "__")
3384 || startswith (t_field_name, "op")
3385 || startswith (t_field_name, "type"))
3386 {
3387 if (cplus_demangle_opname (t_field_name,
3388 dem_opname, DMGL_ANSI))
3389 t_field_name = dem_opname;
3390 else if (cplus_demangle_opname (t_field_name,
3391 dem_opname, 0))
3392 t_field_name = dem_opname;
3393 }
3394 if (t_field_name && strcmp (t_field_name, name) == 0)
3395 {
3396 int j;
3397 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3398 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3399
3400 check_stub_method_group (t, i);
3401
3402 if (intype)
3403 {
3404 for (j = 0; j < len; ++j)
3405 {
3406 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3407 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3408 intype, 1))
3409 break;
3410 }
3411
3412 if (j == len)
3413 error (_("no member function matches "
3414 "that type instantiation"));
3415 }
3416 else
3417 {
3418 int ii;
3419
3420 j = -1;
3421 for (ii = 0; ii < len; ++ii)
3422 {
3423 /* Skip artificial methods. This is necessary if,
3424 for example, the user wants to "print
3425 subclass::subclass" with only one user-defined
3426 constructor. There is no ambiguity in this case.
3427 We are careful here to allow artificial methods
3428 if they are the unique result. */
3429 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3430 {
3431 if (j == -1)
3432 j = ii;
3433 continue;
3434 }
3435
3436 /* Desired method is ambiguous if more than one
3437 method is defined. */
3438 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3439 error (_("non-unique member `%s' requires "
3440 "type instantiation"), name);
3441
3442 j = ii;
3443 }
3444
3445 if (j == -1)
3446 error (_("no matching member function"));
3447 }
3448
3449 if (TYPE_FN_FIELD_STATIC_P (f, j))
3450 {
3451 struct symbol *s =
3452 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3453 0, VAR_DOMAIN, 0).symbol;
3454
3455 if (s == NULL)
3456 return NULL;
3457
3458 if (want_address)
3459 return value_addr (read_var_value (s, 0, 0));
3460 else
3461 return read_var_value (s, 0, 0);
3462 }
3463
3464 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3465 {
3466 if (want_address)
3467 {
3468 result = allocate_value
3469 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3470 cplus_make_method_ptr (value_type (result),
3471 value_contents_writeable (result),
3472 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3473 }
3474 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3475 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3476 else
3477 error (_("Cannot reference virtual member function \"%s\""),
3478 name);
3479 }
3480 else
3481 {
3482 struct symbol *s =
3483 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3484 0, VAR_DOMAIN, 0).symbol;
3485
3486 if (s == NULL)
3487 return NULL;
3488
3489 v = read_var_value (s, 0, 0);
3490 if (!want_address)
3491 result = v;
3492 else
3493 {
3494 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3495 cplus_make_method_ptr (value_type (result),
3496 value_contents_writeable (result),
3497 value_address (v), 0);
3498 }
3499 }
3500 return result;
3501 }
3502 }
3503 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3504 {
3505 struct value *v;
3506 int base_offset;
3507
3508 if (BASETYPE_VIA_VIRTUAL (t, i))
3509 base_offset = 0;
3510 else
3511 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3512 v = value_struct_elt_for_reference (domain,
3513 offset + base_offset,
3514 TYPE_BASECLASS (t, i),
3515 name, intype,
3516 want_address, noside);
3517 if (v)
3518 return v;
3519 }
3520
3521 /* As a last chance, pretend that CURTYPE is a namespace, and look
3522 it up that way; this (frequently) works for types nested inside
3523 classes. */
3524
3525 return value_maybe_namespace_elt (curtype, name,
3526 want_address, noside);
3527 }
3528
3529 /* C++: Return the member NAME of the namespace given by the type
3530 CURTYPE. */
3531
3532 static struct value *
3533 value_namespace_elt (const struct type *curtype,
3534 const char *name, int want_address,
3535 enum noside noside)
3536 {
3537 struct value *retval = value_maybe_namespace_elt (curtype, name,
3538 want_address,
3539 noside);
3540
3541 if (retval == NULL)
3542 error (_("No symbol \"%s\" in namespace \"%s\"."),
3543 name, TYPE_TAG_NAME (curtype));
3544
3545 return retval;
3546 }
3547
3548 /* A helper function used by value_namespace_elt and
3549 value_struct_elt_for_reference. It looks up NAME inside the
3550 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3551 is a class and NAME refers to a type in CURTYPE itself (as opposed
3552 to, say, some base class of CURTYPE). */
3553
3554 static struct value *
3555 value_maybe_namespace_elt (const struct type *curtype,
3556 const char *name, int want_address,
3557 enum noside noside)
3558 {
3559 const char *namespace_name = TYPE_TAG_NAME (curtype);
3560 struct block_symbol sym;
3561 struct value *result;
3562
3563 sym = cp_lookup_symbol_namespace (namespace_name, name,
3564 get_selected_block (0), VAR_DOMAIN);
3565
3566 if (sym.symbol == NULL)
3567 return NULL;
3568 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3569 && (SYMBOL_CLASS (sym.symbol) == LOC_TYPEDEF))
3570 result = allocate_value (SYMBOL_TYPE (sym.symbol));
3571 else
3572 result = value_of_variable (sym.symbol, sym.block);
3573
3574 if (want_address)
3575 result = value_addr (result);
3576
3577 return result;
3578 }
3579
3580 /* Given a pointer or a reference value V, find its real (RTTI) type.
3581
3582 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3583 and refer to the values computed for the object pointed to. */
3584
3585 struct type *
3586 value_rtti_indirect_type (struct value *v, int *full,
3587 int *top, int *using_enc)
3588 {
3589 struct value *target = NULL;
3590 struct type *type, *real_type, *target_type;
3591
3592 type = value_type (v);
3593 type = check_typedef (type);
3594 if (TYPE_CODE (type) == TYPE_CODE_REF)
3595 target = coerce_ref (v);
3596 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3597 {
3598
3599 TRY
3600 {
3601 target = value_ind (v);
3602 }
3603 CATCH (except, RETURN_MASK_ERROR)
3604 {
3605 if (except.error == MEMORY_ERROR)
3606 {
3607 /* value_ind threw a memory error. The pointer is NULL or
3608 contains an uninitialized value: we can't determine any
3609 type. */
3610 return NULL;
3611 }
3612 throw_exception (except);
3613 }
3614 END_CATCH
3615 }
3616 else
3617 return NULL;
3618
3619 real_type = value_rtti_type (target, full, top, using_enc);
3620
3621 if (real_type)
3622 {
3623 /* Copy qualifiers to the referenced object. */
3624 target_type = value_type (target);
3625 real_type = make_cv_type (TYPE_CONST (target_type),
3626 TYPE_VOLATILE (target_type), real_type, NULL);
3627 if (TYPE_CODE (type) == TYPE_CODE_REF)
3628 real_type = lookup_reference_type (real_type);
3629 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3630 real_type = lookup_pointer_type (real_type);
3631 else
3632 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3633
3634 /* Copy qualifiers to the pointer/reference. */
3635 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3636 real_type, NULL);
3637 }
3638
3639 return real_type;
3640 }
3641
3642 /* Given a value pointed to by ARGP, check its real run-time type, and
3643 if that is different from the enclosing type, create a new value
3644 using the real run-time type as the enclosing type (and of the same
3645 type as ARGP) and return it, with the embedded offset adjusted to
3646 be the correct offset to the enclosed object. RTYPE is the type,
3647 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3648 by value_rtti_type(). If these are available, they can be supplied
3649 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3650 NULL if they're not available. */
3651
3652 struct value *
3653 value_full_object (struct value *argp,
3654 struct type *rtype,
3655 int xfull, int xtop,
3656 int xusing_enc)
3657 {
3658 struct type *real_type;
3659 int full = 0;
3660 int top = -1;
3661 int using_enc = 0;
3662 struct value *new_val;
3663
3664 if (rtype)
3665 {
3666 real_type = rtype;
3667 full = xfull;
3668 top = xtop;
3669 using_enc = xusing_enc;
3670 }
3671 else
3672 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3673
3674 /* If no RTTI data, or if object is already complete, do nothing. */
3675 if (!real_type || real_type == value_enclosing_type (argp))
3676 return argp;
3677
3678 /* In a destructor we might see a real type that is a superclass of
3679 the object's type. In this case it is better to leave the object
3680 as-is. */
3681 if (full
3682 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3683 return argp;
3684
3685 /* If we have the full object, but for some reason the enclosing
3686 type is wrong, set it. */
3687 /* pai: FIXME -- sounds iffy */
3688 if (full)
3689 {
3690 argp = value_copy (argp);
3691 set_value_enclosing_type (argp, real_type);
3692 return argp;
3693 }
3694
3695 /* Check if object is in memory. */
3696 if (VALUE_LVAL (argp) != lval_memory)
3697 {
3698 warning (_("Couldn't retrieve complete object of RTTI "
3699 "type %s; object may be in register(s)."),
3700 TYPE_NAME (real_type));
3701
3702 return argp;
3703 }
3704
3705 /* All other cases -- retrieve the complete object. */
3706 /* Go back by the computed top_offset from the beginning of the
3707 object, adjusting for the embedded offset of argp if that's what
3708 value_rtti_type used for its computation. */
3709 new_val = value_at_lazy (real_type, value_address (argp) - top +
3710 (using_enc ? 0 : value_embedded_offset (argp)));
3711 deprecated_set_value_type (new_val, value_type (argp));
3712 set_value_embedded_offset (new_val, (using_enc
3713 ? top + value_embedded_offset (argp)
3714 : top));
3715 return new_val;
3716 }
3717
3718
3719 /* Return the value of the local variable, if one exists. Throw error
3720 otherwise, such as if the request is made in an inappropriate context. */
3721
3722 struct value *
3723 value_of_this (const struct language_defn *lang)
3724 {
3725 struct block_symbol sym;
3726 const struct block *b;
3727 struct frame_info *frame;
3728
3729 if (!lang->la_name_of_this)
3730 error (_("no `this' in current language"));
3731
3732 frame = get_selected_frame (_("no frame selected"));
3733
3734 b = get_frame_block (frame, NULL);
3735
3736 sym = lookup_language_this (lang, b);
3737 if (sym.symbol == NULL)
3738 error (_("current stack frame does not contain a variable named `%s'"),
3739 lang->la_name_of_this);
3740
3741 return read_var_value (sym.symbol, sym.block, frame);
3742 }
3743
3744 /* Return the value of the local variable, if one exists. Return NULL
3745 otherwise. Never throw error. */
3746
3747 struct value *
3748 value_of_this_silent (const struct language_defn *lang)
3749 {
3750 struct value *ret = NULL;
3751
3752 TRY
3753 {
3754 ret = value_of_this (lang);
3755 }
3756 CATCH (except, RETURN_MASK_ERROR)
3757 {
3758 }
3759 END_CATCH
3760
3761 return ret;
3762 }
3763
3764 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3765 elements long, starting at LOWBOUND. The result has the same lower
3766 bound as the original ARRAY. */
3767
3768 struct value *
3769 value_slice (struct value *array, int lowbound, int length)
3770 {
3771 struct type *slice_range_type, *slice_type, *range_type;
3772 LONGEST lowerbound, upperbound;
3773 struct value *slice;
3774 struct type *array_type;
3775
3776 array_type = check_typedef (value_type (array));
3777 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3778 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3779 error (_("cannot take slice of non-array"));
3780
3781 range_type = TYPE_INDEX_TYPE (array_type);
3782 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3783 error (_("slice from bad array or bitstring"));
3784
3785 if (lowbound < lowerbound || length < 0
3786 || lowbound + length - 1 > upperbound)
3787 error (_("slice out of range"));
3788
3789 /* FIXME-type-allocation: need a way to free this type when we are
3790 done with it. */
3791 slice_range_type = create_static_range_type ((struct type *) NULL,
3792 TYPE_TARGET_TYPE (range_type),
3793 lowbound,
3794 lowbound + length - 1);
3795
3796 {
3797 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3798 LONGEST offset
3799 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3800
3801 slice_type = create_array_type ((struct type *) NULL,
3802 element_type,
3803 slice_range_type);
3804 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3805
3806 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3807 slice = allocate_value_lazy (slice_type);
3808 else
3809 {
3810 slice = allocate_value (slice_type);
3811 value_contents_copy (slice, 0, array, offset,
3812 type_length_units (slice_type));
3813 }
3814
3815 set_value_component_location (slice, array);
3816 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3817 set_value_offset (slice, value_offset (array) + offset);
3818 }
3819
3820 return slice;
3821 }
3822
3823 /* Create a value for a FORTRAN complex number. Currently most of the
3824 time values are coerced to COMPLEX*16 (i.e. a complex number
3825 composed of 2 doubles. This really should be a smarter routine
3826 that figures out precision inteligently as opposed to assuming
3827 doubles. FIXME: fmb */
3828
3829 struct value *
3830 value_literal_complex (struct value *arg1,
3831 struct value *arg2,
3832 struct type *type)
3833 {
3834 struct value *val;
3835 struct type *real_type = TYPE_TARGET_TYPE (type);
3836
3837 val = allocate_value (type);
3838 arg1 = value_cast (real_type, arg1);
3839 arg2 = value_cast (real_type, arg2);
3840
3841 memcpy (value_contents_raw (val),
3842 value_contents (arg1), TYPE_LENGTH (real_type));
3843 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3844 value_contents (arg2), TYPE_LENGTH (real_type));
3845 return val;
3846 }
3847
3848 /* Cast a value into the appropriate complex data type. */
3849
3850 static struct value *
3851 cast_into_complex (struct type *type, struct value *val)
3852 {
3853 struct type *real_type = TYPE_TARGET_TYPE (type);
3854
3855 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3856 {
3857 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3858 struct value *re_val = allocate_value (val_real_type);
3859 struct value *im_val = allocate_value (val_real_type);
3860
3861 memcpy (value_contents_raw (re_val),
3862 value_contents (val), TYPE_LENGTH (val_real_type));
3863 memcpy (value_contents_raw (im_val),
3864 value_contents (val) + TYPE_LENGTH (val_real_type),
3865 TYPE_LENGTH (val_real_type));
3866
3867 return value_literal_complex (re_val, im_val, type);
3868 }
3869 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3870 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3871 return value_literal_complex (val,
3872 value_zero (real_type, not_lval),
3873 type);
3874 else
3875 error (_("cannot cast non-number to complex"));
3876 }
3877
3878 void
3879 _initialize_valops (void)
3880 {
3881 add_setshow_boolean_cmd ("overload-resolution", class_support,
3882 &overload_resolution, _("\
3883 Set overload resolution in evaluating C++ functions."), _("\
3884 Show overload resolution in evaluating C++ functions."),
3885 NULL, NULL,
3886 show_overload_resolution,
3887 &setlist, &showlist);
3888 overload_resolution = 1;
3889 }