1 /* Perform non-arithmetic operations on values, for GDB.
3 Copyright (C) 1986-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
35 #include "dictionary.h"
36 #include "cp-support.h"
38 #include "tracepoint.h"
41 #include "exceptions.h"
42 #include "extension.h"
44 extern unsigned int overload_debug;
45 /* Local functions. */
47 static int typecmp (int staticp, int varargs, int nargs,
48 struct field t1[], struct value *t2[]);
50 static struct value *search_struct_field (const char *, struct value *,
51 int, struct type *, int);
53 static struct value *search_struct_method (const char *, struct value **,
55 int, int *, struct type *);
57 static int find_oload_champ_namespace (struct value **, int,
58 const char *, const char *,
60 struct badness_vector **,
64 int find_oload_champ_namespace_loop (struct value **, int,
65 const char *, const char *,
66 int, struct symbol ***,
67 struct badness_vector **, int *,
70 static int find_oload_champ (struct value **, int, int,
71 struct fn_field *, VEC (xmethod_worker_ptr) *,
72 struct symbol **, struct badness_vector **);
74 static int oload_method_static_p (struct fn_field *, int);
76 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
79 oload_classification classify_oload_match (struct badness_vector *,
82 static struct value *value_struct_elt_for_reference (struct type *,
88 static struct value *value_namespace_elt (const struct type *,
89 const char *, int , enum noside);
91 static struct value *value_maybe_namespace_elt (const struct type *,
95 static CORE_ADDR allocate_space_in_inferior (int);
97 static struct value *cast_into_complex (struct type *, struct value *);
99 static void find_method_list (struct value **, const char *,
100 int, struct type *, struct fn_field **, int *,
101 VEC (xmethod_worker_ptr) **,
102 struct type **, int *);
104 void _initialize_valops (void);
107 /* Flag for whether we want to abandon failed expression evals by
110 static int auto_abandon = 0;
113 int overload_resolution = 0;
115 show_overload_resolution (struct ui_file *file, int from_tty,
116 struct cmd_list_element *c,
119 fprintf_filtered (file, _("Overload resolution in evaluating "
120 "C++ functions is %s.\n"),
124 /* Find the address of function name NAME in the inferior. If OBJF_P
125 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
129 find_function_in_inferior (const char *name, struct objfile **objf_p)
133 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
136 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
138 error (_("\"%s\" exists in this program but is not a function."),
143 *objf_p = SYMBOL_SYMTAB (sym)->objfile;
145 return value_of_variable (sym, NULL);
149 struct bound_minimal_symbol msymbol =
150 lookup_bound_minimal_symbol (name);
152 if (msymbol.minsym != NULL)
154 struct objfile *objfile = msymbol.objfile;
155 struct gdbarch *gdbarch = get_objfile_arch (objfile);
159 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
160 type = lookup_function_type (type);
161 type = lookup_pointer_type (type);
162 maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
167 return value_from_pointer (type, maddr);
171 if (!target_has_execution)
172 error (_("evaluation of this expression "
173 "requires the target program to be active"));
175 error (_("evaluation of this expression requires the "
176 "program to have a function \"%s\"."),
182 /* Allocate NBYTES of space in the inferior using the inferior's
183 malloc and return a value that is a pointer to the allocated
187 value_allocate_space_in_inferior (int len)
189 struct objfile *objf;
190 struct value *val = find_function_in_inferior ("malloc", &objf);
191 struct gdbarch *gdbarch = get_objfile_arch (objf);
192 struct value *blocklen;
194 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
195 val = call_function_by_hand (val, 1, &blocklen);
196 if (value_logical_not (val))
198 if (!target_has_execution)
199 error (_("No memory available to program now: "
200 "you need to start the target first"));
202 error (_("No memory available to program: call to malloc failed"));
208 allocate_space_in_inferior (int len)
210 return value_as_long (value_allocate_space_in_inferior (len));
213 /* Cast struct value VAL to type TYPE and return as a value.
214 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
215 for this to work. Typedef to one of the codes is permitted.
216 Returns NULL if the cast is neither an upcast nor a downcast. */
218 static struct value *
219 value_cast_structs (struct type *type, struct value *v2)
225 gdb_assert (type != NULL && v2 != NULL);
227 t1 = check_typedef (type);
228 t2 = check_typedef (value_type (v2));
230 /* Check preconditions. */
231 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
232 || TYPE_CODE (t1) == TYPE_CODE_UNION)
233 && !!"Precondition is that type is of STRUCT or UNION kind.");
234 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
235 || TYPE_CODE (t2) == TYPE_CODE_UNION)
236 && !!"Precondition is that value is of STRUCT or UNION kind");
238 if (TYPE_NAME (t1) != NULL
239 && TYPE_NAME (t2) != NULL
240 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
243 /* Upcasting: look in the type of the source to see if it contains the
244 type of the target as a superclass. If so, we'll need to
245 offset the pointer rather than just change its type. */
246 if (TYPE_NAME (t1) != NULL)
248 v = search_struct_field (type_name_no_tag (t1),
254 /* Downcasting: look in the type of the target to see if it contains the
255 type of the source as a superclass. If so, we'll need to
256 offset the pointer rather than just change its type. */
257 if (TYPE_NAME (t2) != NULL)
259 /* Try downcasting using the run-time type of the value. */
260 int full, top, using_enc;
261 struct type *real_type;
263 real_type = value_rtti_type (v2, &full, &top, &using_enc);
266 v = value_full_object (v2, real_type, full, top, using_enc);
267 v = value_at_lazy (real_type, value_address (v));
268 real_type = value_type (v);
270 /* We might be trying to cast to the outermost enclosing
271 type, in which case search_struct_field won't work. */
272 if (TYPE_NAME (real_type) != NULL
273 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
276 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
281 /* Try downcasting using information from the destination type
282 T2. This wouldn't work properly for classes with virtual
283 bases, but those were handled above. */
284 v = search_struct_field (type_name_no_tag (t2),
285 value_zero (t1, not_lval), 0, t1, 1);
288 /* Downcasting is possible (t1 is superclass of v2). */
289 CORE_ADDR addr2 = value_address (v2);
291 addr2 -= value_address (v) + value_embedded_offset (v);
292 return value_at (type, addr2);
299 /* Cast one pointer or reference type to another. Both TYPE and
300 the type of ARG2 should be pointer types, or else both should be
301 reference types. If SUBCLASS_CHECK is non-zero, this will force a
302 check to see whether TYPE is a superclass of ARG2's type. If
303 SUBCLASS_CHECK is zero, then the subclass check is done only when
304 ARG2 is itself non-zero. Returns the new pointer or reference. */
307 value_cast_pointers (struct type *type, struct value *arg2,
310 struct type *type1 = check_typedef (type);
311 struct type *type2 = check_typedef (value_type (arg2));
312 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
313 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
315 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
316 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
317 && (subclass_check || !value_logical_not (arg2)))
321 if (TYPE_CODE (type2) == TYPE_CODE_REF)
322 v2 = coerce_ref (arg2);
324 v2 = value_ind (arg2);
325 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
326 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
327 v2 = value_cast_structs (t1, v2);
328 /* At this point we have what we can have, un-dereference if needed. */
331 struct value *v = value_addr (v2);
333 deprecated_set_value_type (v, type);
338 /* No superclass found, just change the pointer type. */
339 arg2 = value_copy (arg2);
340 deprecated_set_value_type (arg2, type);
341 set_value_enclosing_type (arg2, type);
342 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
346 /* Cast value ARG2 to type TYPE and return as a value.
347 More general than a C cast: accepts any two types of the same length,
348 and if ARG2 is an lvalue it can be cast into anything at all. */
349 /* In C++, casts may change pointer or object representations. */
352 value_cast (struct type *type, struct value *arg2)
354 enum type_code code1;
355 enum type_code code2;
359 int convert_to_boolean = 0;
361 if (value_type (arg2) == type)
364 code1 = TYPE_CODE (check_typedef (type));
366 /* Check if we are casting struct reference to struct reference. */
367 if (code1 == TYPE_CODE_REF)
369 /* We dereference type; then we recurse and finally
370 we generate value of the given reference. Nothing wrong with
372 struct type *t1 = check_typedef (type);
373 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
374 struct value *val = value_cast (dereftype, arg2);
376 return value_ref (val);
379 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
381 if (code2 == TYPE_CODE_REF)
382 /* We deref the value and then do the cast. */
383 return value_cast (type, coerce_ref (arg2));
385 CHECK_TYPEDEF (type);
386 code1 = TYPE_CODE (type);
387 arg2 = coerce_ref (arg2);
388 type2 = check_typedef (value_type (arg2));
390 /* You can't cast to a reference type. See value_cast_pointers
392 gdb_assert (code1 != TYPE_CODE_REF);
394 /* A cast to an undetermined-length array_type, such as
395 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
396 where N is sizeof(OBJECT)/sizeof(TYPE). */
397 if (code1 == TYPE_CODE_ARRAY)
399 struct type *element_type = TYPE_TARGET_TYPE (type);
400 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
402 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
404 struct type *range_type = TYPE_INDEX_TYPE (type);
405 int val_length = TYPE_LENGTH (type2);
406 LONGEST low_bound, high_bound, new_length;
408 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
409 low_bound = 0, high_bound = 0;
410 new_length = val_length / element_length;
411 if (val_length % element_length != 0)
412 warning (_("array element type size does not "
413 "divide object size in cast"));
414 /* FIXME-type-allocation: need a way to free this type when
415 we are done with it. */
416 range_type = create_static_range_type ((struct type *) NULL,
417 TYPE_TARGET_TYPE (range_type),
419 new_length + low_bound - 1);
420 deprecated_set_value_type (arg2,
421 create_array_type ((struct type *) NULL,
428 if (current_language->c_style_arrays
429 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
430 && !TYPE_VECTOR (type2))
431 arg2 = value_coerce_array (arg2);
433 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
434 arg2 = value_coerce_function (arg2);
436 type2 = check_typedef (value_type (arg2));
437 code2 = TYPE_CODE (type2);
439 if (code1 == TYPE_CODE_COMPLEX)
440 return cast_into_complex (type, arg2);
441 if (code1 == TYPE_CODE_BOOL)
443 code1 = TYPE_CODE_INT;
444 convert_to_boolean = 1;
446 if (code1 == TYPE_CODE_CHAR)
447 code1 = TYPE_CODE_INT;
448 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
449 code2 = TYPE_CODE_INT;
451 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
452 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
453 || code2 == TYPE_CODE_RANGE);
455 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
456 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
457 && TYPE_NAME (type) != 0)
459 struct value *v = value_cast_structs (type, arg2);
465 if (code1 == TYPE_CODE_FLT && scalar)
466 return value_from_double (type, value_as_double (arg2));
467 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
469 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
470 int dec_len = TYPE_LENGTH (type);
473 if (code2 == TYPE_CODE_FLT)
474 decimal_from_floating (arg2, dec, dec_len, byte_order);
475 else if (code2 == TYPE_CODE_DECFLOAT)
476 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
477 byte_order, dec, dec_len, byte_order);
479 /* The only option left is an integral type. */
480 decimal_from_integral (arg2, dec, dec_len, byte_order);
482 return value_from_decfloat (type, dec);
484 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
485 || code1 == TYPE_CODE_RANGE)
486 && (scalar || code2 == TYPE_CODE_PTR
487 || code2 == TYPE_CODE_MEMBERPTR))
491 /* When we cast pointers to integers, we mustn't use
492 gdbarch_pointer_to_address to find the address the pointer
493 represents, as value_as_long would. GDB should evaluate
494 expressions just as the compiler would --- and the compiler
495 sees a cast as a simple reinterpretation of the pointer's
497 if (code2 == TYPE_CODE_PTR)
498 longest = extract_unsigned_integer
499 (value_contents (arg2), TYPE_LENGTH (type2),
500 gdbarch_byte_order (get_type_arch (type2)));
502 longest = value_as_long (arg2);
503 return value_from_longest (type, convert_to_boolean ?
504 (LONGEST) (longest ? 1 : 0) : longest);
506 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
507 || code2 == TYPE_CODE_ENUM
508 || code2 == TYPE_CODE_RANGE))
510 /* TYPE_LENGTH (type) is the length of a pointer, but we really
511 want the length of an address! -- we are really dealing with
512 addresses (i.e., gdb representations) not pointers (i.e.,
513 target representations) here.
515 This allows things like "print *(int *)0x01000234" to work
516 without printing a misleading message -- which would
517 otherwise occur when dealing with a target having two byte
518 pointers and four byte addresses. */
520 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
521 LONGEST longest = value_as_long (arg2);
523 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
525 if (longest >= ((LONGEST) 1 << addr_bit)
526 || longest <= -((LONGEST) 1 << addr_bit))
527 warning (_("value truncated"));
529 return value_from_longest (type, longest);
531 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
532 && value_as_long (arg2) == 0)
534 struct value *result = allocate_value (type);
536 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
539 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
540 && value_as_long (arg2) == 0)
542 /* The Itanium C++ ABI represents NULL pointers to members as
543 minus one, instead of biasing the normal case. */
544 return value_from_longest (type, -1);
546 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
547 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
548 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
549 error (_("Cannot convert between vector values of different sizes"));
550 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
551 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
552 error (_("can only cast scalar to vector of same size"));
553 else if (code1 == TYPE_CODE_VOID)
555 return value_zero (type, not_lval);
557 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
559 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
560 return value_cast_pointers (type, arg2, 0);
562 arg2 = value_copy (arg2);
563 deprecated_set_value_type (arg2, type);
564 set_value_enclosing_type (arg2, type);
565 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
568 else if (VALUE_LVAL (arg2) == lval_memory)
569 return value_at_lazy (type, value_address (arg2));
572 error (_("Invalid cast."));
577 /* The C++ reinterpret_cast operator. */
580 value_reinterpret_cast (struct type *type, struct value *arg)
582 struct value *result;
583 struct type *real_type = check_typedef (type);
584 struct type *arg_type, *dest_type;
586 enum type_code dest_code, arg_code;
588 /* Do reference, function, and array conversion. */
589 arg = coerce_array (arg);
591 /* Attempt to preserve the type the user asked for. */
594 /* If we are casting to a reference type, transform
595 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
596 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
599 arg = value_addr (arg);
600 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
601 real_type = lookup_pointer_type (real_type);
604 arg_type = value_type (arg);
606 dest_code = TYPE_CODE (real_type);
607 arg_code = TYPE_CODE (arg_type);
609 /* We can convert pointer types, or any pointer type to int, or int
611 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
612 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
613 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
614 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
615 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
616 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
617 || (dest_code == arg_code
618 && (dest_code == TYPE_CODE_PTR
619 || dest_code == TYPE_CODE_METHODPTR
620 || dest_code == TYPE_CODE_MEMBERPTR)))
621 result = value_cast (dest_type, arg);
623 error (_("Invalid reinterpret_cast"));
626 result = value_cast (type, value_ref (value_ind (result)));
631 /* A helper for value_dynamic_cast. This implements the first of two
632 runtime checks: we iterate over all the base classes of the value's
633 class which are equal to the desired class; if only one of these
634 holds the value, then it is the answer. */
637 dynamic_cast_check_1 (struct type *desired_type,
638 const gdb_byte *valaddr,
642 struct type *search_type,
644 struct type *arg_type,
645 struct value **result)
647 int i, result_count = 0;
649 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
651 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
654 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
656 if (address + embedded_offset + offset >= arg_addr
657 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
661 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
662 address + embedded_offset + offset);
666 result_count += dynamic_cast_check_1 (desired_type,
668 embedded_offset + offset,
670 TYPE_BASECLASS (search_type, i),
679 /* A helper for value_dynamic_cast. This implements the second of two
680 runtime checks: we look for a unique public sibling class of the
681 argument's declared class. */
684 dynamic_cast_check_2 (struct type *desired_type,
685 const gdb_byte *valaddr,
689 struct type *search_type,
690 struct value **result)
692 int i, result_count = 0;
694 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
698 if (! BASETYPE_VIA_PUBLIC (search_type, i))
701 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
703 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
707 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
708 address + embedded_offset + offset);
711 result_count += dynamic_cast_check_2 (desired_type,
713 embedded_offset + offset,
715 TYPE_BASECLASS (search_type, i),
722 /* The C++ dynamic_cast operator. */
725 value_dynamic_cast (struct type *type, struct value *arg)
727 int full, top, using_enc;
728 struct type *resolved_type = check_typedef (type);
729 struct type *arg_type = check_typedef (value_type (arg));
730 struct type *class_type, *rtti_type;
731 struct value *result, *tem, *original_arg = arg;
733 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
735 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
736 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
737 error (_("Argument to dynamic_cast must be a pointer or reference type"));
738 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
739 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS)
740 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
742 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
743 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
745 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
746 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
747 && value_as_long (arg) == 0))
748 error (_("Argument to dynamic_cast does not have pointer type"));
749 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
751 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
752 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
753 error (_("Argument to dynamic_cast does "
754 "not have pointer to class type"));
757 /* Handle NULL pointers. */
758 if (value_as_long (arg) == 0)
759 return value_zero (type, not_lval);
761 arg = value_ind (arg);
765 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS)
766 error (_("Argument to dynamic_cast does not have class type"));
769 /* If the classes are the same, just return the argument. */
770 if (class_types_same_p (class_type, arg_type))
771 return value_cast (type, arg);
773 /* If the target type is a unique base class of the argument's
774 declared type, just cast it. */
775 if (is_ancestor (class_type, arg_type))
777 if (is_unique_ancestor (class_type, arg))
778 return value_cast (type, original_arg);
779 error (_("Ambiguous dynamic_cast"));
782 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
784 error (_("Couldn't determine value's most derived type for dynamic_cast"));
786 /* Compute the most derived object's address. */
787 addr = value_address (arg);
795 addr += top + value_embedded_offset (arg);
797 /* dynamic_cast<void *> means to return a pointer to the
798 most-derived object. */
799 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
800 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
801 return value_at_lazy (type, addr);
803 tem = value_at (type, addr);
804 type = value_type (tem);
806 /* The first dynamic check specified in 5.2.7. */
807 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
809 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
812 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
813 value_contents_for_printing (tem),
814 value_embedded_offset (tem),
815 value_address (tem), tem,
819 return value_cast (type,
820 is_ref ? value_ref (result) : value_addr (result));
823 /* The second dynamic check specified in 5.2.7. */
825 if (is_public_ancestor (arg_type, rtti_type)
826 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
827 value_contents_for_printing (tem),
828 value_embedded_offset (tem),
829 value_address (tem), tem,
830 rtti_type, &result) == 1)
831 return value_cast (type,
832 is_ref ? value_ref (result) : value_addr (result));
834 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
835 return value_zero (type, not_lval);
837 error (_("dynamic_cast failed"));
840 /* Create a value of type TYPE that is zero, and return it. */
843 value_zero (struct type *type, enum lval_type lv)
845 struct value *val = allocate_value (type);
847 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
851 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
854 value_one (struct type *type)
856 struct type *type1 = check_typedef (type);
859 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
861 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
864 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
865 val = value_from_decfloat (type, v);
867 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
869 val = value_from_double (type, (DOUBLEST) 1);
871 else if (is_integral_type (type1))
873 val = value_from_longest (type, (LONGEST) 1);
875 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
877 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
879 LONGEST low_bound, high_bound;
882 if (!get_array_bounds (type1, &low_bound, &high_bound))
883 error (_("Could not determine the vector bounds"));
885 val = allocate_value (type);
886 for (i = 0; i < high_bound - low_bound + 1; i++)
888 tmp = value_one (eltype);
889 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
890 value_contents_all (tmp), TYPE_LENGTH (eltype));
895 error (_("Not a numeric type."));
898 /* value_one result is never used for assignments to. */
899 gdb_assert (VALUE_LVAL (val) == not_lval);
904 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
905 The type of the created value may differ from the passed type TYPE.
906 Make sure to retrieve the returned values's new type after this call
907 e.g. in case the type is a variable length array. */
909 static struct value *
910 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
914 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
915 error (_("Attempt to dereference a generic pointer."));
917 val = value_from_contents_and_address (type, NULL, addr);
920 value_fetch_lazy (val);
925 /* Return a value with type TYPE located at ADDR.
927 Call value_at only if the data needs to be fetched immediately;
928 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
929 value_at_lazy instead. value_at_lazy simply records the address of
930 the data and sets the lazy-evaluation-required flag. The lazy flag
931 is tested in the value_contents macro, which is used if and when
932 the contents are actually required. The type of the created value
933 may differ from the passed type TYPE. Make sure to retrieve the
934 returned values's new type after this call e.g. in case the type
935 is a variable length array.
937 Note: value_at does *NOT* handle embedded offsets; perform such
938 adjustments before or after calling it. */
941 value_at (struct type *type, CORE_ADDR addr)
943 return get_value_at (type, addr, 0);
946 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
947 The type of the created value may differ from the passed type TYPE.
948 Make sure to retrieve the returned values's new type after this call
949 e.g. in case the type is a variable length array. */
952 value_at_lazy (struct type *type, CORE_ADDR addr)
954 return get_value_at (type, addr, 1);
958 read_value_memory (struct value *val, int embedded_offset,
959 int stack, CORE_ADDR memaddr,
960 gdb_byte *buffer, size_t length)
964 while (xfered < length)
966 enum target_xfer_status status;
969 status = target_xfer_partial (current_target.beneath,
970 TARGET_OBJECT_MEMORY, NULL,
971 buffer + xfered, NULL,
972 memaddr + xfered, length - xfered,
975 if (status == TARGET_XFER_OK)
977 else if (status == TARGET_XFER_UNAVAILABLE)
978 mark_value_bytes_unavailable (val, embedded_offset + xfered,
980 else if (status == TARGET_XFER_EOF)
981 memory_error (TARGET_XFER_E_IO, memaddr + xfered);
983 memory_error (status, memaddr + xfered);
985 xfered += xfered_len;
990 /* Store the contents of FROMVAL into the location of TOVAL.
991 Return a new value with the location of TOVAL and contents of FROMVAL. */
994 value_assign (struct value *toval, struct value *fromval)
998 struct frame_id old_frame;
1000 if (!deprecated_value_modifiable (toval))
1001 error (_("Left operand of assignment is not a modifiable lvalue."));
1003 toval = coerce_ref (toval);
1005 type = value_type (toval);
1006 if (VALUE_LVAL (toval) != lval_internalvar)
1007 fromval = value_cast (type, fromval);
1010 /* Coerce arrays and functions to pointers, except for arrays
1011 which only live in GDB's storage. */
1012 if (!value_must_coerce_to_target (fromval))
1013 fromval = coerce_array (fromval);
1016 CHECK_TYPEDEF (type);
1018 /* Since modifying a register can trash the frame chain, and
1019 modifying memory can trash the frame cache, we save the old frame
1020 and then restore the new frame afterwards. */
1021 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1023 switch (VALUE_LVAL (toval))
1025 case lval_internalvar:
1026 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1027 return value_of_internalvar (get_type_arch (type),
1028 VALUE_INTERNALVAR (toval));
1030 case lval_internalvar_component:
1032 int offset = value_offset (toval);
1034 /* Are we dealing with a bitfield?
1036 It is important to mention that `value_parent (toval)' is
1037 non-NULL iff `value_bitsize (toval)' is non-zero. */
1038 if (value_bitsize (toval))
1040 /* VALUE_INTERNALVAR below refers to the parent value, while
1041 the offset is relative to this parent value. */
1042 gdb_assert (value_parent (value_parent (toval)) == NULL);
1043 offset += value_offset (value_parent (toval));
1046 set_internalvar_component (VALUE_INTERNALVAR (toval),
1048 value_bitpos (toval),
1049 value_bitsize (toval),
1056 const gdb_byte *dest_buffer;
1057 CORE_ADDR changed_addr;
1059 gdb_byte buffer[sizeof (LONGEST)];
1061 if (value_bitsize (toval))
1063 struct value *parent = value_parent (toval);
1065 changed_addr = value_address (parent) + value_offset (toval);
1066 changed_len = (value_bitpos (toval)
1067 + value_bitsize (toval)
1068 + HOST_CHAR_BIT - 1)
1071 /* If we can read-modify-write exactly the size of the
1072 containing type (e.g. short or int) then do so. This
1073 is safer for volatile bitfields mapped to hardware
1075 if (changed_len < TYPE_LENGTH (type)
1076 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1077 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1078 changed_len = TYPE_LENGTH (type);
1080 if (changed_len > (int) sizeof (LONGEST))
1081 error (_("Can't handle bitfields which "
1082 "don't fit in a %d bit word."),
1083 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1085 read_memory (changed_addr, buffer, changed_len);
1086 modify_field (type, buffer, value_as_long (fromval),
1087 value_bitpos (toval), value_bitsize (toval));
1088 dest_buffer = buffer;
1092 changed_addr = value_address (toval);
1093 changed_len = TYPE_LENGTH (type);
1094 dest_buffer = value_contents (fromval);
1097 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1103 struct frame_info *frame;
1104 struct gdbarch *gdbarch;
1107 /* Figure out which frame this is in currently. */
1108 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1109 value_reg = VALUE_REGNUM (toval);
1112 error (_("Value being assigned to is no longer active."));
1114 gdbarch = get_frame_arch (frame);
1116 if (value_bitsize (toval))
1118 struct value *parent = value_parent (toval);
1119 int offset = value_offset (parent) + value_offset (toval);
1121 gdb_byte buffer[sizeof (LONGEST)];
1124 changed_len = (value_bitpos (toval)
1125 + value_bitsize (toval)
1126 + HOST_CHAR_BIT - 1)
1129 if (changed_len > (int) sizeof (LONGEST))
1130 error (_("Can't handle bitfields which "
1131 "don't fit in a %d bit word."),
1132 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1134 if (!get_frame_register_bytes (frame, value_reg, offset,
1135 changed_len, buffer,
1139 throw_error (OPTIMIZED_OUT_ERROR,
1140 _("value has been optimized out"));
1142 throw_error (NOT_AVAILABLE_ERROR,
1143 _("value is not available"));
1146 modify_field (type, buffer, value_as_long (fromval),
1147 value_bitpos (toval), value_bitsize (toval));
1149 put_frame_register_bytes (frame, value_reg, offset,
1150 changed_len, buffer);
1154 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1157 /* If TOVAL is a special machine register requiring
1158 conversion of program values to a special raw
1160 gdbarch_value_to_register (gdbarch, frame,
1161 VALUE_REGNUM (toval), type,
1162 value_contents (fromval));
1166 put_frame_register_bytes (frame, value_reg,
1167 value_offset (toval),
1169 value_contents (fromval));
1173 if (deprecated_register_changed_hook)
1174 deprecated_register_changed_hook (-1);
1180 const struct lval_funcs *funcs = value_computed_funcs (toval);
1182 if (funcs->write != NULL)
1184 funcs->write (toval, fromval);
1191 error (_("Left operand of assignment is not an lvalue."));
1194 /* Assigning to the stack pointer, frame pointer, and other
1195 (architecture and calling convention specific) registers may
1196 cause the frame cache and regcache to be out of date. Assigning to memory
1197 also can. We just do this on all assignments to registers or
1198 memory, for simplicity's sake; I doubt the slowdown matters. */
1199 switch (VALUE_LVAL (toval))
1205 observer_notify_target_changed (¤t_target);
1207 /* Having destroyed the frame cache, restore the selected
1210 /* FIXME: cagney/2002-11-02: There has to be a better way of
1211 doing this. Instead of constantly saving/restoring the
1212 frame. Why not create a get_selected_frame() function that,
1213 having saved the selected frame's ID can automatically
1214 re-find the previously selected frame automatically. */
1217 struct frame_info *fi = frame_find_by_id (old_frame);
1228 /* If the field does not entirely fill a LONGEST, then zero the sign
1229 bits. If the field is signed, and is negative, then sign
1231 if ((value_bitsize (toval) > 0)
1232 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1234 LONGEST fieldval = value_as_long (fromval);
1235 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1237 fieldval &= valmask;
1238 if (!TYPE_UNSIGNED (type)
1239 && (fieldval & (valmask ^ (valmask >> 1))))
1240 fieldval |= ~valmask;
1242 fromval = value_from_longest (type, fieldval);
1245 /* The return value is a copy of TOVAL so it shares its location
1246 information, but its contents are updated from FROMVAL. This
1247 implies the returned value is not lazy, even if TOVAL was. */
1248 val = value_copy (toval);
1249 set_value_lazy (val, 0);
1250 memcpy (value_contents_raw (val), value_contents (fromval),
1251 TYPE_LENGTH (type));
1253 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1254 in the case of pointer types. For object types, the enclosing type
1255 and embedded offset must *not* be copied: the target object refered
1256 to by TOVAL retains its original dynamic type after assignment. */
1257 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1259 set_value_enclosing_type (val, value_enclosing_type (fromval));
1260 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1266 /* Extend a value VAL to COUNT repetitions of its type. */
1269 value_repeat (struct value *arg1, int count)
1273 if (VALUE_LVAL (arg1) != lval_memory)
1274 error (_("Only values in memory can be extended with '@'."));
1276 error (_("Invalid number %d of repetitions."), count);
1278 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1280 VALUE_LVAL (val) = lval_memory;
1281 set_value_address (val, value_address (arg1));
1283 read_value_memory (val, 0, value_stack (val), value_address (val),
1284 value_contents_all_raw (val),
1285 TYPE_LENGTH (value_enclosing_type (val)));
1291 value_of_variable (struct symbol *var, const struct block *b)
1293 struct frame_info *frame;
1295 if (!symbol_read_needs_frame (var))
1298 frame = get_selected_frame (_("No frame selected."));
1301 frame = block_innermost_frame (b);
1304 if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
1305 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
1306 error (_("No frame is currently executing in block %s."),
1307 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
1309 error (_("No frame is currently executing in specified block"));
1313 return read_var_value (var, frame);
1317 address_of_variable (struct symbol *var, const struct block *b)
1319 struct type *type = SYMBOL_TYPE (var);
1322 /* Evaluate it first; if the result is a memory address, we're fine.
1323 Lazy evaluation pays off here. */
1325 val = value_of_variable (var, b);
1326 type = value_type (val);
1328 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1329 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1331 CORE_ADDR addr = value_address (val);
1333 return value_from_pointer (lookup_pointer_type (type), addr);
1336 /* Not a memory address; check what the problem was. */
1337 switch (VALUE_LVAL (val))
1341 struct frame_info *frame;
1342 const char *regname;
1344 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1347 regname = gdbarch_register_name (get_frame_arch (frame),
1348 VALUE_REGNUM (val));
1349 gdb_assert (regname && *regname);
1351 error (_("Address requested for identifier "
1352 "\"%s\" which is in register $%s"),
1353 SYMBOL_PRINT_NAME (var), regname);
1358 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1359 SYMBOL_PRINT_NAME (var));
1366 /* Return one if VAL does not live in target memory, but should in order
1367 to operate on it. Otherwise return zero. */
1370 value_must_coerce_to_target (struct value *val)
1372 struct type *valtype;
1374 /* The only lval kinds which do not live in target memory. */
1375 if (VALUE_LVAL (val) != not_lval
1376 && VALUE_LVAL (val) != lval_internalvar
1377 && VALUE_LVAL (val) != lval_xcallable)
1380 valtype = check_typedef (value_type (val));
1382 switch (TYPE_CODE (valtype))
1384 case TYPE_CODE_ARRAY:
1385 return TYPE_VECTOR (valtype) ? 0 : 1;
1386 case TYPE_CODE_STRING:
1393 /* Make sure that VAL lives in target memory if it's supposed to. For
1394 instance, strings are constructed as character arrays in GDB's
1395 storage, and this function copies them to the target. */
1398 value_coerce_to_target (struct value *val)
1403 if (!value_must_coerce_to_target (val))
1406 length = TYPE_LENGTH (check_typedef (value_type (val)));
1407 addr = allocate_space_in_inferior (length);
1408 write_memory (addr, value_contents (val), length);
1409 return value_at_lazy (value_type (val), addr);
1412 /* Given a value which is an array, return a value which is a pointer
1413 to its first element, regardless of whether or not the array has a
1414 nonzero lower bound.
1416 FIXME: A previous comment here indicated that this routine should
1417 be substracting the array's lower bound. It's not clear to me that
1418 this is correct. Given an array subscripting operation, it would
1419 certainly work to do the adjustment here, essentially computing:
1421 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1423 However I believe a more appropriate and logical place to account
1424 for the lower bound is to do so in value_subscript, essentially
1427 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1429 As further evidence consider what would happen with operations
1430 other than array subscripting, where the caller would get back a
1431 value that had an address somewhere before the actual first element
1432 of the array, and the information about the lower bound would be
1433 lost because of the coercion to pointer type. */
1436 value_coerce_array (struct value *arg1)
1438 struct type *type = check_typedef (value_type (arg1));
1440 /* If the user tries to do something requiring a pointer with an
1441 array that has not yet been pushed to the target, then this would
1442 be a good time to do so. */
1443 arg1 = value_coerce_to_target (arg1);
1445 if (VALUE_LVAL (arg1) != lval_memory)
1446 error (_("Attempt to take address of value not located in memory."));
1448 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1449 value_address (arg1));
1452 /* Given a value which is a function, return a value which is a pointer
1456 value_coerce_function (struct value *arg1)
1458 struct value *retval;
1460 if (VALUE_LVAL (arg1) != lval_memory)
1461 error (_("Attempt to take address of value not located in memory."));
1463 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1464 value_address (arg1));
1468 /* Return a pointer value for the object for which ARG1 is the
1472 value_addr (struct value *arg1)
1475 struct type *type = check_typedef (value_type (arg1));
1477 if (TYPE_CODE (type) == TYPE_CODE_REF)
1479 /* Copy the value, but change the type from (T&) to (T*). We
1480 keep the same location information, which is efficient, and
1481 allows &(&X) to get the location containing the reference. */
1482 arg2 = value_copy (arg1);
1483 deprecated_set_value_type (arg2,
1484 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1487 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1488 return value_coerce_function (arg1);
1490 /* If this is an array that has not yet been pushed to the target,
1491 then this would be a good time to force it to memory. */
1492 arg1 = value_coerce_to_target (arg1);
1494 if (VALUE_LVAL (arg1) != lval_memory)
1495 error (_("Attempt to take address of value not located in memory."));
1497 /* Get target memory address. */
1498 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1499 (value_address (arg1)
1500 + value_embedded_offset (arg1)));
1502 /* This may be a pointer to a base subobject; so remember the
1503 full derived object's type ... */
1504 set_value_enclosing_type (arg2,
1505 lookup_pointer_type (value_enclosing_type (arg1)));
1506 /* ... and also the relative position of the subobject in the full
1508 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1512 /* Return a reference value for the object for which ARG1 is the
1516 value_ref (struct value *arg1)
1519 struct type *type = check_typedef (value_type (arg1));
1521 if (TYPE_CODE (type) == TYPE_CODE_REF)
1524 arg2 = value_addr (arg1);
1525 deprecated_set_value_type (arg2, lookup_reference_type (type));
1529 /* Given a value of a pointer type, apply the C unary * operator to
1533 value_ind (struct value *arg1)
1535 struct type *base_type;
1538 arg1 = coerce_array (arg1);
1540 base_type = check_typedef (value_type (arg1));
1542 if (VALUE_LVAL (arg1) == lval_computed)
1544 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1546 if (funcs->indirect)
1548 struct value *result = funcs->indirect (arg1);
1555 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1557 struct type *enc_type;
1559 /* We may be pointing to something embedded in a larger object.
1560 Get the real type of the enclosing object. */
1561 enc_type = check_typedef (value_enclosing_type (arg1));
1562 enc_type = TYPE_TARGET_TYPE (enc_type);
1564 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1565 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1566 /* For functions, go through find_function_addr, which knows
1567 how to handle function descriptors. */
1568 arg2 = value_at_lazy (enc_type,
1569 find_function_addr (arg1, NULL));
1571 /* Retrieve the enclosing object pointed to. */
1572 arg2 = value_at_lazy (enc_type,
1573 (value_as_address (arg1)
1574 - value_pointed_to_offset (arg1)));
1576 enc_type = value_type (arg2);
1577 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1580 error (_("Attempt to take contents of a non-pointer value."));
1581 return 0; /* For lint -- never reached. */
1584 /* Create a value for an array by allocating space in GDB, copying the
1585 data into that space, and then setting up an array value.
1587 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1588 is populated from the values passed in ELEMVEC.
1590 The element type of the array is inherited from the type of the
1591 first element, and all elements must have the same size (though we
1592 don't currently enforce any restriction on their types). */
1595 value_array (int lowbound, int highbound, struct value **elemvec)
1599 unsigned int typelength;
1601 struct type *arraytype;
1603 /* Validate that the bounds are reasonable and that each of the
1604 elements have the same size. */
1606 nelem = highbound - lowbound + 1;
1609 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1611 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0]));
1612 for (idx = 1; idx < nelem; idx++)
1614 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength)
1616 error (_("array elements must all be the same size"));
1620 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1621 lowbound, highbound);
1623 if (!current_language->c_style_arrays)
1625 val = allocate_value (arraytype);
1626 for (idx = 0; idx < nelem; idx++)
1627 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1632 /* Allocate space to store the array, and then initialize it by
1633 copying in each element. */
1635 val = allocate_value (arraytype);
1636 for (idx = 0; idx < nelem; idx++)
1637 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1642 value_cstring (char *ptr, ssize_t len, struct type *char_type)
1645 int lowbound = current_language->string_lower_bound;
1646 ssize_t highbound = len / TYPE_LENGTH (char_type);
1647 struct type *stringtype
1648 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1650 val = allocate_value (stringtype);
1651 memcpy (value_contents_raw (val), ptr, len);
1655 /* Create a value for a string constant by allocating space in the
1656 inferior, copying the data into that space, and returning the
1657 address with type TYPE_CODE_STRING. PTR points to the string
1658 constant data; LEN is number of characters.
1660 Note that string types are like array of char types with a lower
1661 bound of zero and an upper bound of LEN - 1. Also note that the
1662 string may contain embedded null bytes. */
1665 value_string (char *ptr, ssize_t len, struct type *char_type)
1668 int lowbound = current_language->string_lower_bound;
1669 ssize_t highbound = len / TYPE_LENGTH (char_type);
1670 struct type *stringtype
1671 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1673 val = allocate_value (stringtype);
1674 memcpy (value_contents_raw (val), ptr, len);
1679 /* See if we can pass arguments in T2 to a function which takes
1680 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1681 a NULL-terminated vector. If some arguments need coercion of some
1682 sort, then the coerced values are written into T2. Return value is
1683 0 if the arguments could be matched, or the position at which they
1686 STATICP is nonzero if the T1 argument list came from a static
1687 member function. T2 will still include the ``this'' pointer, but
1690 For non-static member functions, we ignore the first argument,
1691 which is the type of the instance variable. This is because we
1692 want to handle calls with objects from derived classes. This is
1693 not entirely correct: we should actually check to make sure that a
1694 requested operation is type secure, shouldn't we? FIXME. */
1697 typecmp (int staticp, int varargs, int nargs,
1698 struct field t1[], struct value *t2[])
1703 internal_error (__FILE__, __LINE__,
1704 _("typecmp: no argument list"));
1706 /* Skip ``this'' argument if applicable. T2 will always include
1712 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1715 struct type *tt1, *tt2;
1720 tt1 = check_typedef (t1[i].type);
1721 tt2 = check_typedef (value_type (t2[i]));
1723 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1724 /* We should be doing hairy argument matching, as below. */
1725 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1726 == TYPE_CODE (tt2)))
1728 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1729 t2[i] = value_coerce_array (t2[i]);
1731 t2[i] = value_ref (t2[i]);
1735 /* djb - 20000715 - Until the new type structure is in the
1736 place, and we can attempt things like implicit conversions,
1737 we need to do this so you can take something like a map<const
1738 char *>, and properly access map["hello"], because the
1739 argument to [] will be a reference to a pointer to a char,
1740 and the argument will be a pointer to a char. */
1741 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1742 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1744 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1746 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1747 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1748 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1750 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1752 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1754 /* Array to pointer is a `trivial conversion' according to the
1757 /* We should be doing much hairier argument matching (see
1758 section 13.2 of the ARM), but as a quick kludge, just check
1759 for the same type code. */
1760 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1763 if (varargs || t2[i] == NULL)
1768 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1769 and *LAST_BOFFSET, and possibly throws an exception if the field
1770 search has yielded ambiguous results. */
1773 update_search_result (struct value **result_ptr, struct value *v,
1774 int *last_boffset, int boffset,
1775 const char *name, struct type *type)
1779 if (*result_ptr != NULL
1780 /* The result is not ambiguous if all the classes that are
1781 found occupy the same space. */
1782 && *last_boffset != boffset)
1783 error (_("base class '%s' is ambiguous in type '%s'"),
1784 name, TYPE_SAFE_NAME (type));
1786 *last_boffset = boffset;
1790 /* A helper for search_struct_field. This does all the work; most
1791 arguments are as passed to search_struct_field. The result is
1792 stored in *RESULT_PTR, which must be initialized to NULL.
1793 OUTERMOST_TYPE is the type of the initial type passed to
1794 search_struct_field; this is used for error reporting when the
1795 lookup is ambiguous. */
1798 do_search_struct_field (const char *name, struct value *arg1, int offset,
1799 struct type *type, int looking_for_baseclass,
1800 struct value **result_ptr,
1802 struct type *outermost_type)
1807 CHECK_TYPEDEF (type);
1808 nbases = TYPE_N_BASECLASSES (type);
1810 if (!looking_for_baseclass)
1811 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1813 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1815 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1819 if (field_is_static (&TYPE_FIELD (type, i)))
1820 v = value_static_field (type, i);
1822 v = value_primitive_field (arg1, offset, i, type);
1828 && (t_field_name[0] == '\0'
1829 || (TYPE_CODE (type) == TYPE_CODE_UNION
1830 && (strcmp_iw (t_field_name, "else") == 0))))
1832 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1834 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1835 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1837 /* Look for a match through the fields of an anonymous
1838 union, or anonymous struct. C++ provides anonymous
1841 In the GNU Chill (now deleted from GDB)
1842 implementation of variant record types, each
1843 <alternative field> has an (anonymous) union type,
1844 each member of the union represents a <variant
1845 alternative>. Each <variant alternative> is
1846 represented as a struct, with a member for each
1849 struct value *v = NULL;
1850 int new_offset = offset;
1852 /* This is pretty gross. In G++, the offset in an
1853 anonymous union is relative to the beginning of the
1854 enclosing struct. In the GNU Chill (now deleted
1855 from GDB) implementation of variant records, the
1856 bitpos is zero in an anonymous union field, so we
1857 have to add the offset of the union here. */
1858 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1859 || (TYPE_NFIELDS (field_type) > 0
1860 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1861 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1863 do_search_struct_field (name, arg1, new_offset,
1865 looking_for_baseclass, &v,
1877 for (i = 0; i < nbases; i++)
1879 struct value *v = NULL;
1880 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1881 /* If we are looking for baseclasses, this is what we get when
1882 we hit them. But it could happen that the base part's member
1883 name is not yet filled in. */
1884 int found_baseclass = (looking_for_baseclass
1885 && TYPE_BASECLASS_NAME (type, i) != NULL
1886 && (strcmp_iw (name,
1887 TYPE_BASECLASS_NAME (type,
1889 int boffset = value_embedded_offset (arg1) + offset;
1891 if (BASETYPE_VIA_VIRTUAL (type, i))
1895 boffset = baseclass_offset (type, i,
1896 value_contents_for_printing (arg1),
1897 value_embedded_offset (arg1) + offset,
1898 value_address (arg1),
1901 /* The virtual base class pointer might have been clobbered
1902 by the user program. Make sure that it still points to a
1903 valid memory location. */
1905 boffset += value_embedded_offset (arg1) + offset;
1907 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1909 CORE_ADDR base_addr;
1911 base_addr = value_address (arg1) + boffset;
1912 v2 = value_at_lazy (basetype, base_addr);
1913 if (target_read_memory (base_addr,
1914 value_contents_raw (v2),
1915 TYPE_LENGTH (value_type (v2))) != 0)
1916 error (_("virtual baseclass botch"));
1920 v2 = value_copy (arg1);
1921 deprecated_set_value_type (v2, basetype);
1922 set_value_embedded_offset (v2, boffset);
1925 if (found_baseclass)
1929 do_search_struct_field (name, v2, 0,
1930 TYPE_BASECLASS (type, i),
1931 looking_for_baseclass,
1932 result_ptr, last_boffset,
1936 else if (found_baseclass)
1937 v = value_primitive_field (arg1, offset, i, type);
1940 do_search_struct_field (name, arg1,
1941 offset + TYPE_BASECLASS_BITPOS (type,
1943 basetype, looking_for_baseclass,
1944 result_ptr, last_boffset,
1948 update_search_result (result_ptr, v, last_boffset,
1949 boffset, name, outermost_type);
1953 /* Helper function used by value_struct_elt to recurse through
1954 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1955 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1956 TYPE. If found, return value, else return NULL.
1958 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1959 fields, look for a baseclass named NAME. */
1961 static struct value *
1962 search_struct_field (const char *name, struct value *arg1, int offset,
1963 struct type *type, int looking_for_baseclass)
1965 struct value *result = NULL;
1968 do_search_struct_field (name, arg1, offset, type, looking_for_baseclass,
1969 &result, &boffset, type);
1973 /* Helper function used by value_struct_elt to recurse through
1974 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1975 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1978 If found, return value, else if name matched and args not return
1979 (value) -1, else return NULL. */
1981 static struct value *
1982 search_struct_method (const char *name, struct value **arg1p,
1983 struct value **args, int offset,
1984 int *static_memfuncp, struct type *type)
1988 int name_matched = 0;
1989 char dem_opname[64];
1991 CHECK_TYPEDEF (type);
1992 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1994 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1996 /* FIXME! May need to check for ARM demangling here. */
1997 if (strncmp (t_field_name, "__", 2) == 0 ||
1998 strncmp (t_field_name, "op", 2) == 0 ||
1999 strncmp (t_field_name, "type", 4) == 0)
2001 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2002 t_field_name = dem_opname;
2003 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2004 t_field_name = dem_opname;
2006 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2008 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2009 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2012 check_stub_method_group (type, i);
2013 if (j > 0 && args == 0)
2014 error (_("cannot resolve overloaded method "
2015 "`%s': no arguments supplied"), name);
2016 else if (j == 0 && args == 0)
2018 v = value_fn_field (arg1p, f, j, type, offset);
2025 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2026 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2027 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2028 TYPE_FN_FIELD_ARGS (f, j), args))
2030 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2031 return value_virtual_fn_field (arg1p, f, j,
2033 if (TYPE_FN_FIELD_STATIC_P (f, j)
2035 *static_memfuncp = 1;
2036 v = value_fn_field (arg1p, f, j, type, offset);
2045 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2050 if (BASETYPE_VIA_VIRTUAL (type, i))
2052 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2053 struct value *base_val;
2054 const gdb_byte *base_valaddr;
2056 /* The virtual base class pointer might have been
2057 clobbered by the user program. Make sure that it
2058 still points to a valid memory location. */
2060 if (offset < 0 || offset >= TYPE_LENGTH (type))
2063 struct cleanup *back_to;
2066 tmp = xmalloc (TYPE_LENGTH (baseclass));
2067 back_to = make_cleanup (xfree, tmp);
2068 address = value_address (*arg1p);
2070 if (target_read_memory (address + offset,
2071 tmp, TYPE_LENGTH (baseclass)) != 0)
2072 error (_("virtual baseclass botch"));
2074 base_val = value_from_contents_and_address (baseclass,
2077 base_valaddr = value_contents_for_printing (base_val);
2079 do_cleanups (back_to);
2084 base_valaddr = value_contents_for_printing (*arg1p);
2085 this_offset = offset;
2088 base_offset = baseclass_offset (type, i, base_valaddr,
2089 this_offset, value_address (base_val),
2094 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2096 v = search_struct_method (name, arg1p, args, base_offset + offset,
2097 static_memfuncp, TYPE_BASECLASS (type, i));
2098 if (v == (struct value *) - 1)
2104 /* FIXME-bothner: Why is this commented out? Why is it here? */
2105 /* *arg1p = arg1_tmp; */
2110 return (struct value *) - 1;
2115 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2116 extract the component named NAME from the ultimate target
2117 structure/union and return it as a value with its appropriate type.
2118 ERR is used in the error message if *ARGP's type is wrong.
2120 C++: ARGS is a list of argument types to aid in the selection of
2121 an appropriate method. Also, handle derived types.
2123 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2124 where the truthvalue of whether the function that was resolved was
2125 a static member function or not is stored.
2127 ERR is an error message to be printed in case the field is not
2131 value_struct_elt (struct value **argp, struct value **args,
2132 const char *name, int *static_memfuncp, const char *err)
2137 *argp = coerce_array (*argp);
2139 t = check_typedef (value_type (*argp));
2141 /* Follow pointers until we get to a non-pointer. */
2143 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2145 *argp = value_ind (*argp);
2146 /* Don't coerce fn pointer to fn and then back again! */
2147 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2148 *argp = coerce_array (*argp);
2149 t = check_typedef (value_type (*argp));
2152 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2153 && TYPE_CODE (t) != TYPE_CODE_UNION)
2154 error (_("Attempt to extract a component of a value that is not a %s."),
2157 /* Assume it's not, unless we see that it is. */
2158 if (static_memfuncp)
2159 *static_memfuncp = 0;
2163 /* if there are no arguments ...do this... */
2165 /* Try as a field first, because if we succeed, there is less
2167 v = search_struct_field (name, *argp, 0, t, 0);
2171 /* C++: If it was not found as a data field, then try to
2172 return it as a pointer to a method. */
2173 v = search_struct_method (name, argp, args, 0,
2174 static_memfuncp, t);
2176 if (v == (struct value *) - 1)
2177 error (_("Cannot take address of method %s."), name);
2180 if (TYPE_NFN_FIELDS (t))
2181 error (_("There is no member or method named %s."), name);
2183 error (_("There is no member named %s."), name);
2188 v = search_struct_method (name, argp, args, 0,
2189 static_memfuncp, t);
2191 if (v == (struct value *) - 1)
2193 error (_("One of the arguments you tried to pass to %s could not "
2194 "be converted to what the function wants."), name);
2198 /* See if user tried to invoke data as function. If so, hand it
2199 back. If it's not callable (i.e., a pointer to function),
2200 gdb should give an error. */
2201 v = search_struct_field (name, *argp, 0, t, 0);
2202 /* If we found an ordinary field, then it is not a method call.
2203 So, treat it as if it were a static member function. */
2204 if (v && static_memfuncp)
2205 *static_memfuncp = 1;
2209 throw_error (NOT_FOUND_ERROR,
2210 _("Structure has no component named %s."), name);
2214 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2215 to a structure or union, extract and return its component (field) of
2216 type FTYPE at the specified BITPOS.
2217 Throw an exception on error. */
2220 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2228 *argp = coerce_array (*argp);
2230 t = check_typedef (value_type (*argp));
2232 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2234 *argp = value_ind (*argp);
2235 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2236 *argp = coerce_array (*argp);
2237 t = check_typedef (value_type (*argp));
2240 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2241 && TYPE_CODE (t) != TYPE_CODE_UNION)
2242 error (_("Attempt to extract a component of a value that is not a %s."),
2245 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2247 if (!field_is_static (&TYPE_FIELD (t, i))
2248 && bitpos == TYPE_FIELD_BITPOS (t, i)
2249 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2250 return value_primitive_field (*argp, 0, i, t);
2253 error (_("No field with matching bitpos and type."));
2259 /* Search through the methods of an object (and its bases) to find a
2260 specified method. Return the pointer to the fn_field list FN_LIST of
2261 overloaded instances defined in the source language. If available
2262 and matching, a vector of matching xmethods defined in extension
2263 languages are also returned in XM_WORKER_VEC
2265 Helper function for value_find_oload_list.
2266 ARGP is a pointer to a pointer to a value (the object).
2267 METHOD is a string containing the method name.
2268 OFFSET is the offset within the value.
2269 TYPE is the assumed type of the object.
2270 FN_LIST is the pointer to matching overloaded instances defined in
2271 source language. Since this is a recursive function, *FN_LIST
2272 should be set to NULL when calling this function.
2273 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2274 0 when calling this function.
2275 XM_WORKER_VEC is the vector of matching xmethod workers. *XM_WORKER_VEC
2276 should also be set to NULL when calling this function.
2277 BASETYPE is set to the actual type of the subobject where the
2279 BOFFSET is the offset of the base subobject where the method is found. */
2282 find_method_list (struct value **argp, const char *method,
2283 int offset, struct type *type,
2284 struct fn_field **fn_list, int *num_fns,
2285 VEC (xmethod_worker_ptr) **xm_worker_vec,
2286 struct type **basetype, int *boffset)
2289 struct fn_field *f = NULL;
2290 VEC (xmethod_worker_ptr) *worker_vec = NULL, *new_vec = NULL;
2292 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2293 CHECK_TYPEDEF (type);
2295 /* First check in object itself.
2296 This function is called recursively to search through base classes.
2297 If there is a source method match found at some stage, then we need not
2298 look for source methods in consequent recursive calls. */
2299 if ((*fn_list) == NULL)
2301 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2303 /* pai: FIXME What about operators and type conversions? */
2304 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2306 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2308 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2309 f = TYPE_FN_FIELDLIST1 (type, i);
2316 /* Resolve any stub methods. */
2317 check_stub_method_group (type, i);
2324 /* Unlike source methods, xmethods can be accumulated over successive
2325 recursive calls. In other words, an xmethod named 'm' in a class
2326 will not hide an xmethod named 'm' in its base class(es). We want
2327 it to be this way because xmethods are after all convenience functions
2328 and hence there is no point restricting them with something like method
2329 hiding. Moreover, if hiding is done for xmethods as well, then we will
2330 have to provide a mechanism to un-hide (like the 'using' construct). */
2331 worker_vec = get_matching_xmethod_workers (type, method);
2332 new_vec = VEC_merge (xmethod_worker_ptr, *xm_worker_vec, worker_vec);
2334 VEC_free (xmethod_worker_ptr, *xm_worker_vec);
2335 VEC_free (xmethod_worker_ptr, worker_vec);
2336 *xm_worker_vec = new_vec;
2338 /* If source methods are not found in current class, look for them in the
2339 base classes. We also have to go through the base classes to gather
2340 extension methods. */
2341 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2345 if (BASETYPE_VIA_VIRTUAL (type, i))
2347 base_offset = baseclass_offset (type, i,
2348 value_contents_for_printing (*argp),
2349 value_offset (*argp) + offset,
2350 value_address (*argp), *argp);
2352 else /* Non-virtual base, simply use bit position from debug
2355 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2358 find_method_list (argp, method, base_offset + offset,
2359 TYPE_BASECLASS (type, i), fn_list, num_fns,
2360 xm_worker_vec, basetype, boffset);
2364 /* Return the list of overloaded methods of a specified name. The methods
2365 could be those GDB finds in the binary, or xmethod. Methods found in
2366 the binary are returned in FN_LIST, and xmethods are returned in
2369 ARGP is a pointer to a pointer to a value (the object).
2370 METHOD is the method name.
2371 OFFSET is the offset within the value contents.
2372 FN_LIST is the pointer to matching overloaded instances defined in
2374 NUM_FNS is the number of overloaded instances.
2375 XM_WORKER_VEC is the vector of matching xmethod workers defined in
2376 extension languages.
2377 BASETYPE is set to the type of the base subobject that defines the
2379 BOFFSET is the offset of the base subobject which defines the method. */
2382 value_find_oload_method_list (struct value **argp, const char *method,
2383 int offset, struct fn_field **fn_list,
2385 VEC (xmethod_worker_ptr) **xm_worker_vec,
2386 struct type **basetype, int *boffset)
2390 t = check_typedef (value_type (*argp));
2392 /* Code snarfed from value_struct_elt. */
2393 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2395 *argp = value_ind (*argp);
2396 /* Don't coerce fn pointer to fn and then back again! */
2397 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2398 *argp = coerce_array (*argp);
2399 t = check_typedef (value_type (*argp));
2402 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2403 && TYPE_CODE (t) != TYPE_CODE_UNION)
2404 error (_("Attempt to extract a component of a "
2405 "value that is not a struct or union"));
2407 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2409 /* Clear the lists. */
2412 *xm_worker_vec = NULL;
2414 find_method_list (argp, method, 0, t, fn_list, num_fns, xm_worker_vec,
2418 /* Given an array of arguments (ARGS) (which includes an
2419 entry for "this" in the case of C++ methods), the number of
2420 arguments NARGS, the NAME of a function, and whether it's a method or
2421 not (METHOD), find the best function that matches on the argument types
2422 according to the overload resolution rules.
2424 METHOD can be one of three values:
2425 NON_METHOD for non-member functions.
2426 METHOD: for member functions.
2427 BOTH: used for overload resolution of operators where the
2428 candidates are expected to be either member or non member
2429 functions. In this case the first argument ARGTYPES
2430 (representing 'this') is expected to be a reference to the
2431 target object, and will be dereferenced when attempting the
2434 In the case of class methods, the parameter OBJ is an object value
2435 in which to search for overloaded methods.
2437 In the case of non-method functions, the parameter FSYM is a symbol
2438 corresponding to one of the overloaded functions.
2440 Return value is an integer: 0 -> good match, 10 -> debugger applied
2441 non-standard coercions, 100 -> incompatible.
2443 If a method is being searched for, VALP will hold the value.
2444 If a non-method is being searched for, SYMP will hold the symbol
2447 If a method is being searched for, and it is a static method,
2448 then STATICP will point to a non-zero value.
2450 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2451 ADL overload candidates when performing overload resolution for a fully
2454 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2455 read while picking the best overload match (it may be all zeroes and thus
2456 not have a vtable pointer), in which case skip virtual function lookup.
2457 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2460 Note: This function does *not* check the value of
2461 overload_resolution. Caller must check it to see whether overload
2462 resolution is permitted. */
2465 find_overload_match (struct value **args, int nargs,
2466 const char *name, enum oload_search_type method,
2467 struct value **objp, struct symbol *fsym,
2468 struct value **valp, struct symbol **symp,
2469 int *staticp, const int no_adl,
2470 const enum noside noside)
2472 struct value *obj = (objp ? *objp : NULL);
2473 struct type *obj_type = obj ? value_type (obj) : NULL;
2474 /* Index of best overloaded function. */
2475 int func_oload_champ = -1;
2476 int method_oload_champ = -1;
2477 int src_method_oload_champ = -1;
2478 int ext_method_oload_champ = -1;
2479 int src_and_ext_equal = 0;
2481 /* The measure for the current best match. */
2482 struct badness_vector *method_badness = NULL;
2483 struct badness_vector *func_badness = NULL;
2484 struct badness_vector *ext_method_badness = NULL;
2485 struct badness_vector *src_method_badness = NULL;
2487 struct value *temp = obj;
2488 /* For methods, the list of overloaded methods. */
2489 struct fn_field *fns_ptr = NULL;
2490 /* For non-methods, the list of overloaded function symbols. */
2491 struct symbol **oload_syms = NULL;
2492 /* For xmethods, the VEC of xmethod workers. */
2493 VEC (xmethod_worker_ptr) *xm_worker_vec = NULL;
2494 /* Number of overloaded instances being considered. */
2496 struct type *basetype = NULL;
2499 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2501 const char *obj_type_name = NULL;
2502 const char *func_name = NULL;
2503 enum oload_classification match_quality;
2504 enum oload_classification method_match_quality = INCOMPATIBLE;
2505 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2506 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2507 enum oload_classification func_match_quality = INCOMPATIBLE;
2509 /* Get the list of overloaded methods or functions. */
2510 if (method == METHOD || method == BOTH)
2514 /* OBJ may be a pointer value rather than the object itself. */
2515 obj = coerce_ref (obj);
2516 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2517 obj = coerce_ref (value_ind (obj));
2518 obj_type_name = TYPE_NAME (value_type (obj));
2520 /* First check whether this is a data member, e.g. a pointer to
2522 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2524 *valp = search_struct_field (name, obj, 0,
2525 check_typedef (value_type (obj)), 0);
2529 do_cleanups (all_cleanups);
2534 /* Retrieve the list of methods with the name NAME. */
2535 value_find_oload_method_list (&temp, name, 0, &fns_ptr, &num_fns,
2536 &xm_worker_vec, &basetype, &boffset);
2537 /* If this is a method only search, and no methods were found
2538 the search has faild. */
2539 if (method == METHOD && (!fns_ptr || !num_fns) && !xm_worker_vec)
2540 error (_("Couldn't find method %s%s%s"),
2542 (obj_type_name && *obj_type_name) ? "::" : "",
2544 /* If we are dealing with stub method types, they should have
2545 been resolved by find_method_list via
2546 value_find_oload_method_list above. */
2549 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL);
2551 src_method_oload_champ = find_oload_champ (args, nargs,
2552 num_fns, fns_ptr, NULL,
2553 NULL, &src_method_badness);
2555 src_method_match_quality = classify_oload_match
2556 (src_method_badness, nargs,
2557 oload_method_static_p (fns_ptr, src_method_oload_champ));
2559 make_cleanup (xfree, src_method_badness);
2562 if (VEC_length (xmethod_worker_ptr, xm_worker_vec) > 0)
2564 ext_method_oload_champ = find_oload_champ (args, nargs,
2565 0, NULL, xm_worker_vec,
2566 NULL, &ext_method_badness);
2567 ext_method_match_quality = classify_oload_match (ext_method_badness,
2569 make_cleanup (xfree, ext_method_badness);
2570 make_cleanup (free_xmethod_worker_vec, xm_worker_vec);
2573 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2575 switch (compare_badness (ext_method_badness, src_method_badness))
2577 case 0: /* Src method and xmethod are equally good. */
2578 src_and_ext_equal = 1;
2579 /* If src method and xmethod are equally good, then
2580 xmethod should be the winner. Hence, fall through to the
2581 case where a xmethod is better than the source
2582 method, except when the xmethod match quality is
2585 case 1: /* Src method and ext method are incompatible. */
2586 /* If ext method match is not standard, then let source method
2587 win. Otherwise, fallthrough to let xmethod win. */
2588 if (ext_method_match_quality != STANDARD)
2590 method_oload_champ = src_method_oload_champ;
2591 method_badness = src_method_badness;
2592 ext_method_oload_champ = -1;
2593 method_match_quality = src_method_match_quality;
2597 case 2: /* Ext method is champion. */
2598 method_oload_champ = ext_method_oload_champ;
2599 method_badness = ext_method_badness;
2600 src_method_oload_champ = -1;
2601 method_match_quality = ext_method_match_quality;
2603 case 3: /* Src method is champion. */
2604 method_oload_champ = src_method_oload_champ;
2605 method_badness = src_method_badness;
2606 ext_method_oload_champ = -1;
2607 method_match_quality = src_method_match_quality;
2610 gdb_assert_not_reached ("Unexpected overload comparison "
2615 else if (src_method_oload_champ >= 0)
2617 method_oload_champ = src_method_oload_champ;
2618 method_badness = src_method_badness;
2619 method_match_quality = src_method_match_quality;
2621 else if (ext_method_oload_champ >= 0)
2623 method_oload_champ = ext_method_oload_champ;
2624 method_badness = ext_method_badness;
2625 method_match_quality = ext_method_match_quality;
2629 if (method == NON_METHOD || method == BOTH)
2631 const char *qualified_name = NULL;
2633 /* If the overload match is being search for both as a method
2634 and non member function, the first argument must now be
2637 args[0] = value_ind (args[0]);
2641 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2643 /* If we have a function with a C++ name, try to extract just
2644 the function part. Do not try this for non-functions (e.g.
2645 function pointers). */
2647 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2652 temp = cp_func_name (qualified_name);
2654 /* If cp_func_name did not remove anything, the name of the
2655 symbol did not include scope or argument types - it was
2656 probably a C-style function. */
2659 make_cleanup (xfree, temp);
2660 if (strcmp (temp, qualified_name) == 0)
2670 qualified_name = name;
2673 /* If there was no C++ name, this must be a C-style function or
2674 not a function at all. Just return the same symbol. Do the
2675 same if cp_func_name fails for some reason. */
2676 if (func_name == NULL)
2679 do_cleanups (all_cleanups);
2683 func_oload_champ = find_oload_champ_namespace (args, nargs,
2690 if (func_oload_champ >= 0)
2691 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2693 make_cleanup (xfree, oload_syms);
2694 make_cleanup (xfree, func_badness);
2697 /* Did we find a match ? */
2698 if (method_oload_champ == -1 && func_oload_champ == -1)
2699 throw_error (NOT_FOUND_ERROR,
2700 _("No symbol \"%s\" in current context."),
2703 /* If we have found both a method match and a function
2704 match, find out which one is better, and calculate match
2706 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2708 switch (compare_badness (func_badness, method_badness))
2710 case 0: /* Top two contenders are equally good. */
2711 /* FIXME: GDB does not support the general ambiguous case.
2712 All candidates should be collected and presented the
2714 error (_("Ambiguous overload resolution"));
2716 case 1: /* Incomparable top contenders. */
2717 /* This is an error incompatible candidates
2718 should not have been proposed. */
2719 error (_("Internal error: incompatible "
2720 "overload candidates proposed"));
2722 case 2: /* Function champion. */
2723 method_oload_champ = -1;
2724 match_quality = func_match_quality;
2726 case 3: /* Method champion. */
2727 func_oload_champ = -1;
2728 match_quality = method_match_quality;
2731 error (_("Internal error: unexpected overload comparison result"));
2737 /* We have either a method match or a function match. */
2738 if (method_oload_champ >= 0)
2739 match_quality = method_match_quality;
2741 match_quality = func_match_quality;
2744 if (match_quality == INCOMPATIBLE)
2746 if (method == METHOD)
2747 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2749 (obj_type_name && *obj_type_name) ? "::" : "",
2752 error (_("Cannot resolve function %s to any overloaded instance"),
2755 else if (match_quality == NON_STANDARD)
2757 if (method == METHOD)
2758 warning (_("Using non-standard conversion to match "
2759 "method %s%s%s to supplied arguments"),
2761 (obj_type_name && *obj_type_name) ? "::" : "",
2764 warning (_("Using non-standard conversion to match "
2765 "function %s to supplied arguments"),
2769 if (staticp != NULL)
2770 *staticp = oload_method_static_p (fns_ptr, method_oload_champ);
2772 if (method_oload_champ >= 0)
2774 if (src_method_oload_champ >= 0)
2776 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)
2777 && noside != EVAL_AVOID_SIDE_EFFECTS)
2779 *valp = value_virtual_fn_field (&temp, fns_ptr,
2780 method_oload_champ, basetype,
2784 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2789 *valp = value_of_xmethod (clone_xmethod_worker
2790 (VEC_index (xmethod_worker_ptr, xm_worker_vec,
2791 ext_method_oload_champ)));
2795 *symp = oload_syms[func_oload_champ];
2799 struct type *temp_type = check_typedef (value_type (temp));
2800 struct type *objtype = check_typedef (obj_type);
2802 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2803 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2804 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2806 temp = value_addr (temp);
2811 do_cleanups (all_cleanups);
2813 switch (match_quality)
2819 default: /* STANDARD */
2824 /* Find the best overload match, searching for FUNC_NAME in namespaces
2825 contained in QUALIFIED_NAME until it either finds a good match or
2826 runs out of namespaces. It stores the overloaded functions in
2827 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2828 calling function is responsible for freeing *OLOAD_SYMS and
2829 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2833 find_oload_champ_namespace (struct value **args, int nargs,
2834 const char *func_name,
2835 const char *qualified_name,
2836 struct symbol ***oload_syms,
2837 struct badness_vector **oload_champ_bv,
2842 find_oload_champ_namespace_loop (args, nargs,
2845 oload_syms, oload_champ_bv,
2852 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2853 how deep we've looked for namespaces, and the champ is stored in
2854 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2855 if it isn't. Other arguments are the same as in
2856 find_oload_champ_namespace
2858 It is the caller's responsibility to free *OLOAD_SYMS and
2862 find_oload_champ_namespace_loop (struct value **args, int nargs,
2863 const char *func_name,
2864 const char *qualified_name,
2866 struct symbol ***oload_syms,
2867 struct badness_vector **oload_champ_bv,
2871 int next_namespace_len = namespace_len;
2872 int searched_deeper = 0;
2874 struct cleanup *old_cleanups;
2875 int new_oload_champ;
2876 struct symbol **new_oload_syms;
2877 struct badness_vector *new_oload_champ_bv;
2878 char *new_namespace;
2880 if (next_namespace_len != 0)
2882 gdb_assert (qualified_name[next_namespace_len] == ':');
2883 next_namespace_len += 2;
2885 next_namespace_len +=
2886 cp_find_first_component (qualified_name + next_namespace_len);
2888 /* Initialize these to values that can safely be xfree'd. */
2890 *oload_champ_bv = NULL;
2892 /* First, see if we have a deeper namespace we can search in.
2893 If we get a good match there, use it. */
2895 if (qualified_name[next_namespace_len] == ':')
2897 searched_deeper = 1;
2899 if (find_oload_champ_namespace_loop (args, nargs,
2900 func_name, qualified_name,
2902 oload_syms, oload_champ_bv,
2903 oload_champ, no_adl))
2909 /* If we reach here, either we're in the deepest namespace or we
2910 didn't find a good match in a deeper namespace. But, in the
2911 latter case, we still have a bad match in a deeper namespace;
2912 note that we might not find any match at all in the current
2913 namespace. (There's always a match in the deepest namespace,
2914 because this overload mechanism only gets called if there's a
2915 function symbol to start off with.) */
2917 old_cleanups = make_cleanup (xfree, *oload_syms);
2918 make_cleanup (xfree, *oload_champ_bv);
2919 new_namespace = alloca (namespace_len + 1);
2920 strncpy (new_namespace, qualified_name, namespace_len);
2921 new_namespace[namespace_len] = '\0';
2922 new_oload_syms = make_symbol_overload_list (func_name,
2925 /* If we have reached the deepest level perform argument
2926 determined lookup. */
2927 if (!searched_deeper && !no_adl)
2930 struct type **arg_types;
2932 /* Prepare list of argument types for overload resolution. */
2933 arg_types = (struct type **)
2934 alloca (nargs * (sizeof (struct type *)));
2935 for (ix = 0; ix < nargs; ix++)
2936 arg_types[ix] = value_type (args[ix]);
2937 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2940 while (new_oload_syms[num_fns])
2943 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2944 NULL, NULL, new_oload_syms,
2945 &new_oload_champ_bv);
2947 /* Case 1: We found a good match. Free earlier matches (if any),
2948 and return it. Case 2: We didn't find a good match, but we're
2949 not the deepest function. Then go with the bad match that the
2950 deeper function found. Case 3: We found a bad match, and we're
2951 the deepest function. Then return what we found, even though
2952 it's a bad match. */
2954 if (new_oload_champ != -1
2955 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2957 *oload_syms = new_oload_syms;
2958 *oload_champ = new_oload_champ;
2959 *oload_champ_bv = new_oload_champ_bv;
2960 do_cleanups (old_cleanups);
2963 else if (searched_deeper)
2965 xfree (new_oload_syms);
2966 xfree (new_oload_champ_bv);
2967 discard_cleanups (old_cleanups);
2972 *oload_syms = new_oload_syms;
2973 *oload_champ = new_oload_champ;
2974 *oload_champ_bv = new_oload_champ_bv;
2975 do_cleanups (old_cleanups);
2980 /* Look for a function to take NARGS args of ARGS. Find
2981 the best match from among the overloaded methods or functions
2982 given by FNS_PTR or OLOAD_SYMS or XM_WORKER_VEC, respectively.
2983 One, and only one of FNS_PTR, OLOAD_SYMS and XM_WORKER_VEC can be
2986 If XM_WORKER_VEC is NULL, then the length of the arrays FNS_PTR
2987 or OLOAD_SYMS (whichever is non-NULL) is specified in NUM_FNS.
2989 Return the index of the best match; store an indication of the
2990 quality of the match in OLOAD_CHAMP_BV.
2992 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2995 find_oload_champ (struct value **args, int nargs,
2996 int num_fns, struct fn_field *fns_ptr,
2997 VEC (xmethod_worker_ptr) *xm_worker_vec,
2998 struct symbol **oload_syms,
2999 struct badness_vector **oload_champ_bv)
3003 int xm_worker_vec_n = VEC_length (xmethod_worker_ptr, xm_worker_vec);
3004 /* A measure of how good an overloaded instance is. */
3005 struct badness_vector *bv;
3006 /* Index of best overloaded function. */
3007 int oload_champ = -1;
3008 /* Current ambiguity state for overload resolution. */
3009 int oload_ambiguous = 0;
3010 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
3012 /* A champion can be found among methods alone, or among functions
3013 alone, or in xmethods alone, but not in more than one of these
3015 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) + (xm_worker_vec != NULL)
3018 *oload_champ_bv = NULL;
3020 fn_count = (xm_worker_vec != NULL
3021 ? VEC_length (xmethod_worker_ptr, xm_worker_vec)
3023 /* Consider each candidate in turn. */
3024 for (ix = 0; ix < fn_count; ix++)
3027 int static_offset = 0;
3029 struct type **parm_types;
3030 struct xmethod_worker *worker = NULL;
3032 if (xm_worker_vec != NULL)
3034 worker = VEC_index (xmethod_worker_ptr, xm_worker_vec, ix);
3035 parm_types = get_xmethod_arg_types (worker, &nparms);
3039 if (fns_ptr != NULL)
3041 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
3042 static_offset = oload_method_static_p (fns_ptr, ix);
3045 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
3047 parm_types = (struct type **)
3048 xmalloc (nparms * (sizeof (struct type *)));
3049 for (jj = 0; jj < nparms; jj++)
3050 parm_types[jj] = (fns_ptr != NULL
3051 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
3052 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
3056 /* Compare parameter types to supplied argument types. Skip
3057 THIS for static methods. */
3058 bv = rank_function (parm_types, nparms,
3059 args + static_offset,
3060 nargs - static_offset);
3062 if (!*oload_champ_bv)
3064 *oload_champ_bv = bv;
3067 else /* See whether current candidate is better or worse than
3069 switch (compare_badness (bv, *oload_champ_bv))
3071 case 0: /* Top two contenders are equally good. */
3072 oload_ambiguous = 1;
3074 case 1: /* Incomparable top contenders. */
3075 oload_ambiguous = 2;
3077 case 2: /* New champion, record details. */
3078 *oload_champ_bv = bv;
3079 oload_ambiguous = 0;
3089 if (fns_ptr != NULL)
3090 fprintf_filtered (gdb_stderr,
3091 "Overloaded method instance %s, # of parms %d\n",
3092 fns_ptr[ix].physname, nparms);
3093 else if (xm_worker_vec != NULL)
3094 fprintf_filtered (gdb_stderr,
3095 "Xmethod worker, # of parms %d\n",
3098 fprintf_filtered (gdb_stderr,
3099 "Overloaded function instance "
3100 "%s # of parms %d\n",
3101 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3103 for (jj = 0; jj < nargs - static_offset; jj++)
3104 fprintf_filtered (gdb_stderr,
3105 "...Badness @ %d : %d\n",
3106 jj, bv->rank[jj].rank);
3107 fprintf_filtered (gdb_stderr, "Overload resolution "
3108 "champion is %d, ambiguous? %d\n",
3109 oload_champ, oload_ambiguous);
3116 /* Return 1 if we're looking at a static method, 0 if we're looking at
3117 a non-static method or a function that isn't a method. */
3120 oload_method_static_p (struct fn_field *fns_ptr, int index)
3122 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3128 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3130 static enum oload_classification
3131 classify_oload_match (struct badness_vector *oload_champ_bv,
3136 enum oload_classification worst = STANDARD;
3138 for (ix = 1; ix <= nargs - static_offset; ix++)
3140 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3141 or worse return INCOMPATIBLE. */
3142 if (compare_ranks (oload_champ_bv->rank[ix],
3143 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3144 return INCOMPATIBLE; /* Truly mismatched types. */
3145 /* Otherwise If this conversion is as bad as
3146 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3147 else if (compare_ranks (oload_champ_bv->rank[ix],
3148 NS_POINTER_CONVERSION_BADNESS) <= 0)
3149 worst = NON_STANDARD; /* Non-standard type conversions
3153 /* If no INCOMPATIBLE classification was found, return the worst one
3154 that was found (if any). */
3158 /* C++: return 1 is NAME is a legitimate name for the destructor of
3159 type TYPE. If TYPE does not have a destructor, or if NAME is
3160 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3161 have CHECK_TYPEDEF applied, this function will apply it itself. */
3164 destructor_name_p (const char *name, struct type *type)
3168 const char *dname = type_name_no_tag_or_error (type);
3169 const char *cp = strchr (dname, '<');
3172 /* Do not compare the template part for template classes. */
3174 len = strlen (dname);
3177 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3178 error (_("name of destructor must equal name of class"));
3185 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3186 class". If the name is found, return a value representing it;
3187 otherwise throw an exception. */
3189 static struct value *
3190 enum_constant_from_type (struct type *type, const char *name)
3193 int name_len = strlen (name);
3195 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3196 && TYPE_DECLARED_CLASS (type));
3198 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3200 const char *fname = TYPE_FIELD_NAME (type, i);
3203 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3207 /* Look for the trailing "::NAME", since enum class constant
3208 names are qualified here. */
3209 len = strlen (fname);
3210 if (len + 2 >= name_len
3211 && fname[len - name_len - 2] == ':'
3212 && fname[len - name_len - 1] == ':'
3213 && strcmp (&fname[len - name_len], name) == 0)
3214 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3217 error (_("no constant named \"%s\" in enum \"%s\""),
3218 name, TYPE_TAG_NAME (type));
3221 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3222 return the appropriate member (or the address of the member, if
3223 WANT_ADDRESS). This function is used to resolve user expressions
3224 of the form "DOMAIN::NAME". For more details on what happens, see
3225 the comment before value_struct_elt_for_reference. */
3228 value_aggregate_elt (struct type *curtype, const char *name,
3229 struct type *expect_type, int want_address,
3232 switch (TYPE_CODE (curtype))
3234 case TYPE_CODE_STRUCT:
3235 case TYPE_CODE_UNION:
3236 return value_struct_elt_for_reference (curtype, 0, curtype,
3238 want_address, noside);
3239 case TYPE_CODE_NAMESPACE:
3240 return value_namespace_elt (curtype, name,
3241 want_address, noside);
3243 case TYPE_CODE_ENUM:
3244 return enum_constant_from_type (curtype, name);
3247 internal_error (__FILE__, __LINE__,
3248 _("non-aggregate type in value_aggregate_elt"));
3252 /* Compares the two method/function types T1 and T2 for "equality"
3253 with respect to the methods' parameters. If the types of the
3254 two parameter lists are the same, returns 1; 0 otherwise. This
3255 comparison may ignore any artificial parameters in T1 if
3256 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3257 the first artificial parameter in T1, assumed to be a 'this' pointer.
3259 The type T2 is expected to have come from make_params (in eval.c). */
3262 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3266 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3269 /* If skipping artificial fields, find the first real field
3271 if (skip_artificial)
3273 while (start < TYPE_NFIELDS (t1)
3274 && TYPE_FIELD_ARTIFICIAL (t1, start))
3278 /* Now compare parameters. */
3280 /* Special case: a method taking void. T1 will contain no
3281 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3282 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3283 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3286 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3290 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3292 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3293 TYPE_FIELD_TYPE (t2, i), NULL),
3294 EXACT_MATCH_BADNESS) != 0)
3304 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3305 return the address of this member as a "pointer to member" type.
3306 If INTYPE is non-null, then it will be the type of the member we
3307 are looking for. This will help us resolve "pointers to member
3308 functions". This function is used to resolve user expressions of
3309 the form "DOMAIN::NAME". */
3311 static struct value *
3312 value_struct_elt_for_reference (struct type *domain, int offset,
3313 struct type *curtype, const char *name,
3314 struct type *intype,
3318 struct type *t = curtype;
3320 struct value *v, *result;
3322 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3323 && TYPE_CODE (t) != TYPE_CODE_UNION)
3324 error (_("Internal error: non-aggregate type "
3325 "to value_struct_elt_for_reference"));
3327 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3329 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3331 if (t_field_name && strcmp (t_field_name, name) == 0)
3333 if (field_is_static (&TYPE_FIELD (t, i)))
3335 v = value_static_field (t, i);
3340 if (TYPE_FIELD_PACKED (t, i))
3341 error (_("pointers to bitfield members not allowed"));
3344 return value_from_longest
3345 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3346 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3347 else if (noside != EVAL_NORMAL)
3348 return allocate_value (TYPE_FIELD_TYPE (t, i));
3351 /* Try to evaluate NAME as a qualified name with implicit
3352 this pointer. In this case, attempt to return the
3353 equivalent to `this->*(&TYPE::NAME)'. */
3354 v = value_of_this_silent (current_language);
3359 struct type *type, *tmp;
3361 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3362 type = check_typedef (value_type (ptr));
3363 gdb_assert (type != NULL
3364 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3365 tmp = lookup_pointer_type (TYPE_DOMAIN_TYPE (type));
3366 v = value_cast_pointers (tmp, v, 1);
3367 mem_offset = value_as_long (ptr);
3368 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3369 result = value_from_pointer (tmp,
3370 value_as_long (v) + mem_offset);
3371 return value_ind (result);
3374 error (_("Cannot reference non-static field \"%s\""), name);
3379 /* C++: If it was not found as a data field, then try to return it
3380 as a pointer to a method. */
3382 /* Perform all necessary dereferencing. */
3383 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3384 intype = TYPE_TARGET_TYPE (intype);
3386 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3388 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3389 char dem_opname[64];
3391 if (strncmp (t_field_name, "__", 2) == 0
3392 || strncmp (t_field_name, "op", 2) == 0
3393 || strncmp (t_field_name, "type", 4) == 0)
3395 if (cplus_demangle_opname (t_field_name,
3396 dem_opname, DMGL_ANSI))
3397 t_field_name = dem_opname;
3398 else if (cplus_demangle_opname (t_field_name,
3400 t_field_name = dem_opname;
3402 if (t_field_name && strcmp (t_field_name, name) == 0)
3405 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3406 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3408 check_stub_method_group (t, i);
3412 for (j = 0; j < len; ++j)
3414 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3415 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3421 error (_("no member function matches "
3422 "that type instantiation"));
3429 for (ii = 0; ii < len; ++ii)
3431 /* Skip artificial methods. This is necessary if,
3432 for example, the user wants to "print
3433 subclass::subclass" with only one user-defined
3434 constructor. There is no ambiguity in this case.
3435 We are careful here to allow artificial methods
3436 if they are the unique result. */
3437 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3444 /* Desired method is ambiguous if more than one
3445 method is defined. */
3446 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3447 error (_("non-unique member `%s' requires "
3448 "type instantiation"), name);
3454 error (_("no matching member function"));
3457 if (TYPE_FN_FIELD_STATIC_P (f, j))
3460 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3467 return value_addr (read_var_value (s, 0));
3469 return read_var_value (s, 0);
3472 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3476 result = allocate_value
3477 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3478 cplus_make_method_ptr (value_type (result),
3479 value_contents_writeable (result),
3480 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3482 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3483 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3485 error (_("Cannot reference virtual member function \"%s\""),
3491 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3497 v = read_var_value (s, 0);
3502 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3503 cplus_make_method_ptr (value_type (result),
3504 value_contents_writeable (result),
3505 value_address (v), 0);
3511 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3516 if (BASETYPE_VIA_VIRTUAL (t, i))
3519 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3520 v = value_struct_elt_for_reference (domain,
3521 offset + base_offset,
3522 TYPE_BASECLASS (t, i),
3524 want_address, noside);
3529 /* As a last chance, pretend that CURTYPE is a namespace, and look
3530 it up that way; this (frequently) works for types nested inside
3533 return value_maybe_namespace_elt (curtype, name,
3534 want_address, noside);
3537 /* C++: Return the member NAME of the namespace given by the type
3540 static struct value *
3541 value_namespace_elt (const struct type *curtype,
3542 const char *name, int want_address,
3545 struct value *retval = value_maybe_namespace_elt (curtype, name,
3550 error (_("No symbol \"%s\" in namespace \"%s\"."),
3551 name, TYPE_TAG_NAME (curtype));
3556 /* A helper function used by value_namespace_elt and
3557 value_struct_elt_for_reference. It looks up NAME inside the
3558 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3559 is a class and NAME refers to a type in CURTYPE itself (as opposed
3560 to, say, some base class of CURTYPE). */
3562 static struct value *
3563 value_maybe_namespace_elt (const struct type *curtype,
3564 const char *name, int want_address,
3567 const char *namespace_name = TYPE_TAG_NAME (curtype);
3569 struct value *result;
3571 sym = cp_lookup_symbol_namespace (namespace_name, name,
3572 get_selected_block (0), VAR_DOMAIN);
3576 char *concatenated_name = alloca (strlen (namespace_name) + 2
3577 + strlen (name) + 1);
3579 sprintf (concatenated_name, "%s::%s", namespace_name, name);
3580 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN);
3585 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3586 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3587 result = allocate_value (SYMBOL_TYPE (sym));
3589 result = value_of_variable (sym, get_selected_block (0));
3591 if (result && want_address)
3592 result = value_addr (result);
3597 /* Given a pointer or a reference value V, find its real (RTTI) type.
3599 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3600 and refer to the values computed for the object pointed to. */
3603 value_rtti_indirect_type (struct value *v, int *full,
3604 int *top, int *using_enc)
3606 struct value *target;
3607 struct type *type, *real_type, *target_type;
3609 type = value_type (v);
3610 type = check_typedef (type);
3611 if (TYPE_CODE (type) == TYPE_CODE_REF)
3612 target = coerce_ref (v);
3613 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3614 target = value_ind (v);
3618 real_type = value_rtti_type (target, full, top, using_enc);
3622 /* Copy qualifiers to the referenced object. */
3623 target_type = value_type (target);
3624 real_type = make_cv_type (TYPE_CONST (target_type),
3625 TYPE_VOLATILE (target_type), real_type, NULL);
3626 if (TYPE_CODE (type) == TYPE_CODE_REF)
3627 real_type = lookup_reference_type (real_type);
3628 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3629 real_type = lookup_pointer_type (real_type);
3631 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3633 /* Copy qualifiers to the pointer/reference. */
3634 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3641 /* Given a value pointed to by ARGP, check its real run-time type, and
3642 if that is different from the enclosing type, create a new value
3643 using the real run-time type as the enclosing type (and of the same
3644 type as ARGP) and return it, with the embedded offset adjusted to
3645 be the correct offset to the enclosed object. RTYPE is the type,
3646 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3647 by value_rtti_type(). If these are available, they can be supplied
3648 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3649 NULL if they're not available. */
3652 value_full_object (struct value *argp,
3654 int xfull, int xtop,
3657 struct type *real_type;
3661 struct value *new_val;
3668 using_enc = xusing_enc;
3671 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3673 /* If no RTTI data, or if object is already complete, do nothing. */
3674 if (!real_type || real_type == value_enclosing_type (argp))
3677 /* In a destructor we might see a real type that is a superclass of
3678 the object's type. In this case it is better to leave the object
3681 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3684 /* If we have the full object, but for some reason the enclosing
3685 type is wrong, set it. */
3686 /* pai: FIXME -- sounds iffy */
3689 argp = value_copy (argp);
3690 set_value_enclosing_type (argp, real_type);
3694 /* Check if object is in memory. */
3695 if (VALUE_LVAL (argp) != lval_memory)
3697 warning (_("Couldn't retrieve complete object of RTTI "
3698 "type %s; object may be in register(s)."),
3699 TYPE_NAME (real_type));
3704 /* All other cases -- retrieve the complete object. */
3705 /* Go back by the computed top_offset from the beginning of the
3706 object, adjusting for the embedded offset of argp if that's what
3707 value_rtti_type used for its computation. */
3708 new_val = value_at_lazy (real_type, value_address (argp) - top +
3709 (using_enc ? 0 : value_embedded_offset (argp)));
3710 deprecated_set_value_type (new_val, value_type (argp));
3711 set_value_embedded_offset (new_val, (using_enc
3712 ? top + value_embedded_offset (argp)
3718 /* Return the value of the local variable, if one exists. Throw error
3719 otherwise, such as if the request is made in an inappropriate context. */
3722 value_of_this (const struct language_defn *lang)
3725 const struct block *b;
3726 struct frame_info *frame;
3728 if (!lang->la_name_of_this)
3729 error (_("no `this' in current language"));
3731 frame = get_selected_frame (_("no frame selected"));
3733 b = get_frame_block (frame, NULL);
3735 sym = lookup_language_this (lang, b);
3737 error (_("current stack frame does not contain a variable named `%s'"),
3738 lang->la_name_of_this);
3740 return read_var_value (sym, frame);
3743 /* Return the value of the local variable, if one exists. Return NULL
3744 otherwise. Never throw error. */
3747 value_of_this_silent (const struct language_defn *lang)
3749 struct value *ret = NULL;
3750 volatile struct gdb_exception except;
3752 TRY_CATCH (except, RETURN_MASK_ERROR)
3754 ret = value_of_this (lang);
3760 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3761 elements long, starting at LOWBOUND. The result has the same lower
3762 bound as the original ARRAY. */
3765 value_slice (struct value *array, int lowbound, int length)
3767 struct type *slice_range_type, *slice_type, *range_type;
3768 LONGEST lowerbound, upperbound;
3769 struct value *slice;
3770 struct type *array_type;
3772 array_type = check_typedef (value_type (array));
3773 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3774 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3775 error (_("cannot take slice of non-array"));
3777 range_type = TYPE_INDEX_TYPE (array_type);
3778 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3779 error (_("slice from bad array or bitstring"));
3781 if (lowbound < lowerbound || length < 0
3782 || lowbound + length - 1 > upperbound)
3783 error (_("slice out of range"));
3785 /* FIXME-type-allocation: need a way to free this type when we are
3787 slice_range_type = create_static_range_type ((struct type *) NULL,
3788 TYPE_TARGET_TYPE (range_type),
3790 lowbound + length - 1);
3793 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3795 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3797 slice_type = create_array_type ((struct type *) NULL,
3800 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3802 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3803 slice = allocate_value_lazy (slice_type);
3806 slice = allocate_value (slice_type);
3807 value_contents_copy (slice, 0, array, offset,
3808 TYPE_LENGTH (slice_type));
3811 set_value_component_location (slice, array);
3812 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3813 set_value_offset (slice, value_offset (array) + offset);
3819 /* Create a value for a FORTRAN complex number. Currently most of the
3820 time values are coerced to COMPLEX*16 (i.e. a complex number
3821 composed of 2 doubles. This really should be a smarter routine
3822 that figures out precision inteligently as opposed to assuming
3823 doubles. FIXME: fmb */
3826 value_literal_complex (struct value *arg1,
3831 struct type *real_type = TYPE_TARGET_TYPE (type);
3833 val = allocate_value (type);
3834 arg1 = value_cast (real_type, arg1);
3835 arg2 = value_cast (real_type, arg2);
3837 memcpy (value_contents_raw (val),
3838 value_contents (arg1), TYPE_LENGTH (real_type));
3839 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3840 value_contents (arg2), TYPE_LENGTH (real_type));
3844 /* Cast a value into the appropriate complex data type. */
3846 static struct value *
3847 cast_into_complex (struct type *type, struct value *val)
3849 struct type *real_type = TYPE_TARGET_TYPE (type);
3851 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3853 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3854 struct value *re_val = allocate_value (val_real_type);
3855 struct value *im_val = allocate_value (val_real_type);
3857 memcpy (value_contents_raw (re_val),
3858 value_contents (val), TYPE_LENGTH (val_real_type));
3859 memcpy (value_contents_raw (im_val),
3860 value_contents (val) + TYPE_LENGTH (val_real_type),
3861 TYPE_LENGTH (val_real_type));
3863 return value_literal_complex (re_val, im_val, type);
3865 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3866 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3867 return value_literal_complex (val,
3868 value_zero (real_type, not_lval),
3871 error (_("cannot cast non-number to complex"));
3875 _initialize_valops (void)
3877 add_setshow_boolean_cmd ("overload-resolution", class_support,
3878 &overload_resolution, _("\
3879 Set overload resolution in evaluating C++ functions."), _("\
3880 Show overload resolution in evaluating C++ functions."),
3882 show_overload_resolution,
3883 &setlist, &showlist);
3884 overload_resolution = 1;