1 /* Perform non-arithmetic operations on values, for GDB.
3 Copyright (C) 1986-2015 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 "extension.h"
43 extern unsigned int overload_debug;
44 /* Local functions. */
46 static int typecmp (int staticp, int varargs, int nargs,
47 struct field t1[], struct value *t2[]);
49 static struct value *search_struct_field (const char *, struct value *,
50 int, struct type *, int);
52 static struct value *search_struct_method (const char *, struct value **,
54 int, int *, struct type *);
56 static int find_oload_champ_namespace (struct value **, int,
57 const char *, const char *,
59 struct badness_vector **,
63 int find_oload_champ_namespace_loop (struct value **, int,
64 const char *, const char *,
65 int, struct symbol ***,
66 struct badness_vector **, int *,
69 static int find_oload_champ (struct value **, int, int,
70 struct fn_field *, VEC (xmethod_worker_ptr) *,
71 struct symbol **, struct badness_vector **);
73 static int oload_method_static_p (struct fn_field *, int);
75 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
78 oload_classification classify_oload_match (struct badness_vector *,
81 static struct value *value_struct_elt_for_reference (struct type *,
87 static struct value *value_namespace_elt (const struct type *,
88 const char *, int , enum noside);
90 static struct value *value_maybe_namespace_elt (const struct type *,
94 static CORE_ADDR allocate_space_in_inferior (int);
96 static struct value *cast_into_complex (struct type *, struct value *);
98 static void find_method_list (struct value **, const char *,
99 int, struct type *, struct fn_field **, int *,
100 VEC (xmethod_worker_ptr) **,
101 struct type **, int *);
103 void _initialize_valops (void);
106 /* Flag for whether we want to abandon failed expression evals by
109 static int auto_abandon = 0;
112 int overload_resolution = 0;
114 show_overload_resolution (struct ui_file *file, int from_tty,
115 struct cmd_list_element *c,
118 fprintf_filtered (file, _("Overload resolution in evaluating "
119 "C++ functions is %s.\n"),
123 /* Find the address of function name NAME in the inferior. If OBJF_P
124 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
128 find_function_in_inferior (const char *name, struct objfile **objf_p)
132 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
135 if (SYMBOL_CLASS (sym) != LOC_BLOCK)
137 error (_("\"%s\" exists in this program but is not a function."),
142 *objf_p = symbol_objfile (sym);
144 return value_of_variable (sym, NULL);
148 struct bound_minimal_symbol msymbol =
149 lookup_bound_minimal_symbol (name);
151 if (msymbol.minsym != NULL)
153 struct objfile *objfile = msymbol.objfile;
154 struct gdbarch *gdbarch = get_objfile_arch (objfile);
158 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
159 type = lookup_function_type (type);
160 type = lookup_pointer_type (type);
161 maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
166 return value_from_pointer (type, maddr);
170 if (!target_has_execution)
171 error (_("evaluation of this expression "
172 "requires the target program to be active"));
174 error (_("evaluation of this expression requires the "
175 "program to have a function \"%s\"."),
181 /* Allocate NBYTES of space in the inferior using the inferior's
182 malloc and return a value that is a pointer to the allocated
186 value_allocate_space_in_inferior (int len)
188 struct objfile *objf;
189 struct value *val = find_function_in_inferior ("malloc", &objf);
190 struct gdbarch *gdbarch = get_objfile_arch (objf);
191 struct value *blocklen;
193 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
194 val = call_function_by_hand (val, 1, &blocklen);
195 if (value_logical_not (val))
197 if (!target_has_execution)
198 error (_("No memory available to program now: "
199 "you need to start the target first"));
201 error (_("No memory available to program: call to malloc failed"));
207 allocate_space_in_inferior (int len)
209 return value_as_long (value_allocate_space_in_inferior (len));
212 /* Cast struct value VAL to type TYPE and return as a value.
213 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
214 for this to work. Typedef to one of the codes is permitted.
215 Returns NULL if the cast is neither an upcast nor a downcast. */
217 static struct value *
218 value_cast_structs (struct type *type, struct value *v2)
224 gdb_assert (type != NULL && v2 != NULL);
226 t1 = check_typedef (type);
227 t2 = check_typedef (value_type (v2));
229 /* Check preconditions. */
230 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT
231 || TYPE_CODE (t1) == TYPE_CODE_UNION)
232 && !!"Precondition is that type is of STRUCT or UNION kind.");
233 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT
234 || TYPE_CODE (t2) == TYPE_CODE_UNION)
235 && !!"Precondition is that value is of STRUCT or UNION kind");
237 if (TYPE_NAME (t1) != NULL
238 && TYPE_NAME (t2) != NULL
239 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2)))
242 /* Upcasting: look in the type of the source to see if it contains the
243 type of the target as a superclass. If so, we'll need to
244 offset the pointer rather than just change its type. */
245 if (TYPE_NAME (t1) != NULL)
247 v = search_struct_field (type_name_no_tag (t1),
253 /* Downcasting: look in the type of the target to see if it contains the
254 type of the source as a superclass. If so, we'll need to
255 offset the pointer rather than just change its type. */
256 if (TYPE_NAME (t2) != NULL)
258 /* Try downcasting using the run-time type of the value. */
259 int full, top, using_enc;
260 struct type *real_type;
262 real_type = value_rtti_type (v2, &full, &top, &using_enc);
265 v = value_full_object (v2, real_type, full, top, using_enc);
266 v = value_at_lazy (real_type, value_address (v));
267 real_type = value_type (v);
269 /* We might be trying to cast to the outermost enclosing
270 type, in which case search_struct_field won't work. */
271 if (TYPE_NAME (real_type) != NULL
272 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1)))
275 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1);
280 /* Try downcasting using information from the destination type
281 T2. This wouldn't work properly for classes with virtual
282 bases, but those were handled above. */
283 v = search_struct_field (type_name_no_tag (t2),
284 value_zero (t1, not_lval), 0, t1, 1);
287 /* Downcasting is possible (t1 is superclass of v2). */
288 CORE_ADDR addr2 = value_address (v2);
290 addr2 -= value_address (v) + value_embedded_offset (v);
291 return value_at (type, addr2);
298 /* Cast one pointer or reference type to another. Both TYPE and
299 the type of ARG2 should be pointer types, or else both should be
300 reference types. If SUBCLASS_CHECK is non-zero, this will force a
301 check to see whether TYPE is a superclass of ARG2's type. If
302 SUBCLASS_CHECK is zero, then the subclass check is done only when
303 ARG2 is itself non-zero. Returns the new pointer or reference. */
306 value_cast_pointers (struct type *type, struct value *arg2,
309 struct type *type1 = check_typedef (type);
310 struct type *type2 = check_typedef (value_type (arg2));
311 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
312 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
314 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT
315 && TYPE_CODE (t2) == TYPE_CODE_STRUCT
316 && (subclass_check || !value_logical_not (arg2)))
320 if (TYPE_CODE (type2) == TYPE_CODE_REF)
321 v2 = coerce_ref (arg2);
323 v2 = value_ind (arg2);
324 gdb_assert (TYPE_CODE (check_typedef (value_type (v2)))
325 == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
326 v2 = value_cast_structs (t1, v2);
327 /* At this point we have what we can have, un-dereference if needed. */
330 struct value *v = value_addr (v2);
332 deprecated_set_value_type (v, type);
337 /* No superclass found, just change the pointer type. */
338 arg2 = value_copy (arg2);
339 deprecated_set_value_type (arg2, type);
340 set_value_enclosing_type (arg2, type);
341 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
345 /* Cast value ARG2 to type TYPE and return as a value.
346 More general than a C cast: accepts any two types of the same length,
347 and if ARG2 is an lvalue it can be cast into anything at all. */
348 /* In C++, casts may change pointer or object representations. */
351 value_cast (struct type *type, struct value *arg2)
353 enum type_code code1;
354 enum type_code code2;
358 int convert_to_boolean = 0;
360 if (value_type (arg2) == type)
363 code1 = TYPE_CODE (check_typedef (type));
365 /* Check if we are casting struct reference to struct reference. */
366 if (code1 == TYPE_CODE_REF)
368 /* We dereference type; then we recurse and finally
369 we generate value of the given reference. Nothing wrong with
371 struct type *t1 = check_typedef (type);
372 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
373 struct value *val = value_cast (dereftype, arg2);
375 return value_ref (val);
378 code2 = TYPE_CODE (check_typedef (value_type (arg2)));
380 if (code2 == TYPE_CODE_REF)
381 /* We deref the value and then do the cast. */
382 return value_cast (type, coerce_ref (arg2));
384 CHECK_TYPEDEF (type);
385 code1 = TYPE_CODE (type);
386 arg2 = coerce_ref (arg2);
387 type2 = check_typedef (value_type (arg2));
389 /* You can't cast to a reference type. See value_cast_pointers
391 gdb_assert (code1 != TYPE_CODE_REF);
393 /* A cast to an undetermined-length array_type, such as
394 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
395 where N is sizeof(OBJECT)/sizeof(TYPE). */
396 if (code1 == TYPE_CODE_ARRAY)
398 struct type *element_type = TYPE_TARGET_TYPE (type);
399 unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
401 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type))
403 struct type *range_type = TYPE_INDEX_TYPE (type);
404 int val_length = TYPE_LENGTH (type2);
405 LONGEST low_bound, high_bound, new_length;
407 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
408 low_bound = 0, high_bound = 0;
409 new_length = val_length / element_length;
410 if (val_length % element_length != 0)
411 warning (_("array element type size does not "
412 "divide object size in cast"));
413 /* FIXME-type-allocation: need a way to free this type when
414 we are done with it. */
415 range_type = create_static_range_type ((struct type *) NULL,
416 TYPE_TARGET_TYPE (range_type),
418 new_length + low_bound - 1);
419 deprecated_set_value_type (arg2,
420 create_array_type ((struct type *) NULL,
427 if (current_language->c_style_arrays
428 && TYPE_CODE (type2) == TYPE_CODE_ARRAY
429 && !TYPE_VECTOR (type2))
430 arg2 = value_coerce_array (arg2);
432 if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
433 arg2 = value_coerce_function (arg2);
435 type2 = check_typedef (value_type (arg2));
436 code2 = TYPE_CODE (type2);
438 if (code1 == TYPE_CODE_COMPLEX)
439 return cast_into_complex (type, arg2);
440 if (code1 == TYPE_CODE_BOOL)
442 code1 = TYPE_CODE_INT;
443 convert_to_boolean = 1;
445 if (code1 == TYPE_CODE_CHAR)
446 code1 = TYPE_CODE_INT;
447 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
448 code2 = TYPE_CODE_INT;
450 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
451 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
452 || code2 == TYPE_CODE_RANGE);
454 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
455 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
456 && TYPE_NAME (type) != 0)
458 struct value *v = value_cast_structs (type, arg2);
464 if (code1 == TYPE_CODE_FLT && scalar)
465 return value_from_double (type, value_as_double (arg2));
466 else if (code1 == TYPE_CODE_DECFLOAT && scalar)
468 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
469 int dec_len = TYPE_LENGTH (type);
472 if (code2 == TYPE_CODE_FLT)
473 decimal_from_floating (arg2, dec, dec_len, byte_order);
474 else if (code2 == TYPE_CODE_DECFLOAT)
475 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2),
476 byte_order, dec, dec_len, byte_order);
478 /* The only option left is an integral type. */
479 decimal_from_integral (arg2, dec, dec_len, byte_order);
481 return value_from_decfloat (type, dec);
483 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
484 || code1 == TYPE_CODE_RANGE)
485 && (scalar || code2 == TYPE_CODE_PTR
486 || code2 == TYPE_CODE_MEMBERPTR))
490 /* When we cast pointers to integers, we mustn't use
491 gdbarch_pointer_to_address to find the address the pointer
492 represents, as value_as_long would. GDB should evaluate
493 expressions just as the compiler would --- and the compiler
494 sees a cast as a simple reinterpretation of the pointer's
496 if (code2 == TYPE_CODE_PTR)
497 longest = extract_unsigned_integer
498 (value_contents (arg2), TYPE_LENGTH (type2),
499 gdbarch_byte_order (get_type_arch (type2)));
501 longest = value_as_long (arg2);
502 return value_from_longest (type, convert_to_boolean ?
503 (LONGEST) (longest ? 1 : 0) : longest);
505 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
506 || code2 == TYPE_CODE_ENUM
507 || code2 == TYPE_CODE_RANGE))
509 /* TYPE_LENGTH (type) is the length of a pointer, but we really
510 want the length of an address! -- we are really dealing with
511 addresses (i.e., gdb representations) not pointers (i.e.,
512 target representations) here.
514 This allows things like "print *(int *)0x01000234" to work
515 without printing a misleading message -- which would
516 otherwise occur when dealing with a target having two byte
517 pointers and four byte addresses. */
519 int addr_bit = gdbarch_addr_bit (get_type_arch (type2));
520 LONGEST longest = value_as_long (arg2);
522 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
524 if (longest >= ((LONGEST) 1 << addr_bit)
525 || longest <= -((LONGEST) 1 << addr_bit))
526 warning (_("value truncated"));
528 return value_from_longest (type, longest);
530 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
531 && value_as_long (arg2) == 0)
533 struct value *result = allocate_value (type);
535 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0);
538 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
539 && value_as_long (arg2) == 0)
541 /* The Itanium C++ ABI represents NULL pointers to members as
542 minus one, instead of biasing the normal case. */
543 return value_from_longest (type, -1);
545 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
546 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2)
547 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
548 error (_("Cannot convert between vector values of different sizes"));
549 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar
550 && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
551 error (_("can only cast scalar to vector of same size"));
552 else if (code1 == TYPE_CODE_VOID)
554 return value_zero (type, not_lval);
556 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
558 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
559 return value_cast_pointers (type, arg2, 0);
561 arg2 = value_copy (arg2);
562 deprecated_set_value_type (arg2, type);
563 set_value_enclosing_type (arg2, type);
564 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
567 else if (VALUE_LVAL (arg2) == lval_memory)
568 return value_at_lazy (type, value_address (arg2));
571 error (_("Invalid cast."));
576 /* The C++ reinterpret_cast operator. */
579 value_reinterpret_cast (struct type *type, struct value *arg)
581 struct value *result;
582 struct type *real_type = check_typedef (type);
583 struct type *arg_type, *dest_type;
585 enum type_code dest_code, arg_code;
587 /* Do reference, function, and array conversion. */
588 arg = coerce_array (arg);
590 /* Attempt to preserve the type the user asked for. */
593 /* If we are casting to a reference type, transform
594 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */
595 if (TYPE_CODE (real_type) == TYPE_CODE_REF)
598 arg = value_addr (arg);
599 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
600 real_type = lookup_pointer_type (real_type);
603 arg_type = value_type (arg);
605 dest_code = TYPE_CODE (real_type);
606 arg_code = TYPE_CODE (arg_type);
608 /* We can convert pointer types, or any pointer type to int, or int
610 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
611 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
612 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
613 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
614 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
615 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
616 || (dest_code == arg_code
617 && (dest_code == TYPE_CODE_PTR
618 || dest_code == TYPE_CODE_METHODPTR
619 || dest_code == TYPE_CODE_MEMBERPTR)))
620 result = value_cast (dest_type, arg);
622 error (_("Invalid reinterpret_cast"));
625 result = value_cast (type, value_ref (value_ind (result)));
630 /* A helper for value_dynamic_cast. This implements the first of two
631 runtime checks: we iterate over all the base classes of the value's
632 class which are equal to the desired class; if only one of these
633 holds the value, then it is the answer. */
636 dynamic_cast_check_1 (struct type *desired_type,
637 const gdb_byte *valaddr,
641 struct type *search_type,
643 struct type *arg_type,
644 struct value **result)
646 int i, result_count = 0;
648 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
650 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
653 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
655 if (address + embedded_offset + offset >= arg_addr
656 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
660 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
661 address + embedded_offset + offset);
665 result_count += dynamic_cast_check_1 (desired_type,
667 embedded_offset + offset,
669 TYPE_BASECLASS (search_type, i),
678 /* A helper for value_dynamic_cast. This implements the second of two
679 runtime checks: we look for a unique public sibling class of the
680 argument's declared class. */
683 dynamic_cast_check_2 (struct type *desired_type,
684 const gdb_byte *valaddr,
688 struct type *search_type,
689 struct value **result)
691 int i, result_count = 0;
693 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
697 if (! BASETYPE_VIA_PUBLIC (search_type, i))
700 offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
702 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
706 *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
707 address + embedded_offset + offset);
710 result_count += dynamic_cast_check_2 (desired_type,
712 embedded_offset + offset,
714 TYPE_BASECLASS (search_type, i),
721 /* The C++ dynamic_cast operator. */
724 value_dynamic_cast (struct type *type, struct value *arg)
726 int full, top, using_enc;
727 struct type *resolved_type = check_typedef (type);
728 struct type *arg_type = check_typedef (value_type (arg));
729 struct type *class_type, *rtti_type;
730 struct value *result, *tem, *original_arg = arg;
732 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF;
734 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR
735 && TYPE_CODE (resolved_type) != TYPE_CODE_REF)
736 error (_("Argument to dynamic_cast must be a pointer or reference type"));
737 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID
738 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_STRUCT)
739 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
741 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
742 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
744 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR
745 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT
746 && value_as_long (arg) == 0))
747 error (_("Argument to dynamic_cast does not have pointer type"));
748 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR)
750 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
751 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
752 error (_("Argument to dynamic_cast does "
753 "not have pointer to class type"));
756 /* Handle NULL pointers. */
757 if (value_as_long (arg) == 0)
758 return value_zero (type, not_lval);
760 arg = value_ind (arg);
764 if (TYPE_CODE (arg_type) != TYPE_CODE_STRUCT)
765 error (_("Argument to dynamic_cast does not have class type"));
768 /* If the classes are the same, just return the argument. */
769 if (class_types_same_p (class_type, arg_type))
770 return value_cast (type, arg);
772 /* If the target type is a unique base class of the argument's
773 declared type, just cast it. */
774 if (is_ancestor (class_type, arg_type))
776 if (is_unique_ancestor (class_type, arg))
777 return value_cast (type, original_arg);
778 error (_("Ambiguous dynamic_cast"));
781 rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
783 error (_("Couldn't determine value's most derived type for dynamic_cast"));
785 /* Compute the most derived object's address. */
786 addr = value_address (arg);
794 addr += top + value_embedded_offset (arg);
796 /* dynamic_cast<void *> means to return a pointer to the
797 most-derived object. */
798 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR
799 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID)
800 return value_at_lazy (type, addr);
802 tem = value_at (type, addr);
803 type = value_type (tem);
805 /* The first dynamic check specified in 5.2.7. */
806 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
808 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
811 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
812 value_contents_for_printing (tem),
813 value_embedded_offset (tem),
814 value_address (tem), tem,
818 return value_cast (type,
819 is_ref ? value_ref (result) : value_addr (result));
822 /* The second dynamic check specified in 5.2.7. */
824 if (is_public_ancestor (arg_type, rtti_type)
825 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
826 value_contents_for_printing (tem),
827 value_embedded_offset (tem),
828 value_address (tem), tem,
829 rtti_type, &result) == 1)
830 return value_cast (type,
831 is_ref ? value_ref (result) : value_addr (result));
833 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
834 return value_zero (type, not_lval);
836 error (_("dynamic_cast failed"));
839 /* Create a value of type TYPE that is zero, and return it. */
842 value_zero (struct type *type, enum lval_type lv)
844 struct value *val = allocate_value (type);
846 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
850 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
853 value_one (struct type *type)
855 struct type *type1 = check_typedef (type);
858 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT)
860 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
863 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1");
864 val = value_from_decfloat (type, v);
866 else if (TYPE_CODE (type1) == TYPE_CODE_FLT)
868 val = value_from_double (type, (DOUBLEST) 1);
870 else if (is_integral_type (type1))
872 val = value_from_longest (type, (LONGEST) 1);
874 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1))
876 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
878 LONGEST low_bound, high_bound;
881 if (!get_array_bounds (type1, &low_bound, &high_bound))
882 error (_("Could not determine the vector bounds"));
884 val = allocate_value (type);
885 for (i = 0; i < high_bound - low_bound + 1; i++)
887 tmp = value_one (eltype);
888 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype),
889 value_contents_all (tmp), TYPE_LENGTH (eltype));
894 error (_("Not a numeric type."));
897 /* value_one result is never used for assignments to. */
898 gdb_assert (VALUE_LVAL (val) == not_lval);
903 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
904 The type of the created value may differ from the passed type TYPE.
905 Make sure to retrieve the returned values's new type after this call
906 e.g. in case the type is a variable length array. */
908 static struct value *
909 get_value_at (struct type *type, CORE_ADDR addr, int lazy)
913 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
914 error (_("Attempt to dereference a generic pointer."));
916 val = value_from_contents_and_address (type, NULL, addr);
919 value_fetch_lazy (val);
924 /* Return a value with type TYPE located at ADDR.
926 Call value_at only if the data needs to be fetched immediately;
927 if we can be 'lazy' and defer the fetch, perhaps indefinately, call
928 value_at_lazy instead. value_at_lazy simply records the address of
929 the data and sets the lazy-evaluation-required flag. The lazy flag
930 is tested in the value_contents macro, which is used if and when
931 the contents are actually required. The type of the created value
932 may differ from the passed type TYPE. Make sure to retrieve the
933 returned values's new type after this call e.g. in case the type
934 is a variable length array.
936 Note: value_at does *NOT* handle embedded offsets; perform such
937 adjustments before or after calling it. */
940 value_at (struct type *type, CORE_ADDR addr)
942 return get_value_at (type, addr, 0);
945 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
946 The type of the created value may differ from the passed type TYPE.
947 Make sure to retrieve the returned values's new type after this call
948 e.g. in case the type is a variable length array. */
951 value_at_lazy (struct type *type, CORE_ADDR addr)
953 return get_value_at (type, addr, 1);
957 read_value_memory (struct value *val, int embedded_offset,
958 int stack, CORE_ADDR memaddr,
959 gdb_byte *buffer, size_t length)
963 while (xfered < length)
965 enum target_xfer_status status;
968 status = target_xfer_partial (current_target.beneath,
969 TARGET_OBJECT_MEMORY, NULL,
970 buffer + xfered, NULL,
971 memaddr + xfered, length - xfered,
974 if (status == TARGET_XFER_OK)
976 else if (status == TARGET_XFER_UNAVAILABLE)
977 mark_value_bytes_unavailable (val, embedded_offset + xfered,
979 else if (status == TARGET_XFER_EOF)
980 memory_error (TARGET_XFER_E_IO, memaddr + xfered);
982 memory_error (status, memaddr + xfered);
984 xfered += xfered_len;
989 /* Store the contents of FROMVAL into the location of TOVAL.
990 Return a new value with the location of TOVAL and contents of FROMVAL. */
993 value_assign (struct value *toval, struct value *fromval)
997 struct frame_id old_frame;
999 if (!deprecated_value_modifiable (toval))
1000 error (_("Left operand of assignment is not a modifiable lvalue."));
1002 toval = coerce_ref (toval);
1004 type = value_type (toval);
1005 if (VALUE_LVAL (toval) != lval_internalvar)
1006 fromval = value_cast (type, fromval);
1009 /* Coerce arrays and functions to pointers, except for arrays
1010 which only live in GDB's storage. */
1011 if (!value_must_coerce_to_target (fromval))
1012 fromval = coerce_array (fromval);
1015 CHECK_TYPEDEF (type);
1017 /* Since modifying a register can trash the frame chain, and
1018 modifying memory can trash the frame cache, we save the old frame
1019 and then restore the new frame afterwards. */
1020 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1022 switch (VALUE_LVAL (toval))
1024 case lval_internalvar:
1025 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1026 return value_of_internalvar (get_type_arch (type),
1027 VALUE_INTERNALVAR (toval));
1029 case lval_internalvar_component:
1031 int offset = value_offset (toval);
1033 /* Are we dealing with a bitfield?
1035 It is important to mention that `value_parent (toval)' is
1036 non-NULL iff `value_bitsize (toval)' is non-zero. */
1037 if (value_bitsize (toval))
1039 /* VALUE_INTERNALVAR below refers to the parent value, while
1040 the offset is relative to this parent value. */
1041 gdb_assert (value_parent (value_parent (toval)) == NULL);
1042 offset += value_offset (value_parent (toval));
1045 set_internalvar_component (VALUE_INTERNALVAR (toval),
1047 value_bitpos (toval),
1048 value_bitsize (toval),
1055 const gdb_byte *dest_buffer;
1056 CORE_ADDR changed_addr;
1058 gdb_byte buffer[sizeof (LONGEST)];
1060 if (value_bitsize (toval))
1062 struct value *parent = value_parent (toval);
1064 changed_addr = value_address (parent) + value_offset (toval);
1065 changed_len = (value_bitpos (toval)
1066 + value_bitsize (toval)
1067 + HOST_CHAR_BIT - 1)
1070 /* If we can read-modify-write exactly the size of the
1071 containing type (e.g. short or int) then do so. This
1072 is safer for volatile bitfields mapped to hardware
1074 if (changed_len < TYPE_LENGTH (type)
1075 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1076 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1077 changed_len = TYPE_LENGTH (type);
1079 if (changed_len > (int) sizeof (LONGEST))
1080 error (_("Can't handle bitfields which "
1081 "don't fit in a %d bit word."),
1082 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1084 read_memory (changed_addr, buffer, changed_len);
1085 modify_field (type, buffer, value_as_long (fromval),
1086 value_bitpos (toval), value_bitsize (toval));
1087 dest_buffer = buffer;
1091 changed_addr = value_address (toval);
1092 changed_len = TYPE_LENGTH (type);
1093 dest_buffer = value_contents (fromval);
1096 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1102 struct frame_info *frame;
1103 struct gdbarch *gdbarch;
1106 /* Figure out which frame this is in currently. */
1107 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1108 value_reg = VALUE_REGNUM (toval);
1111 error (_("Value being assigned to is no longer active."));
1113 gdbarch = get_frame_arch (frame);
1115 if (value_bitsize (toval))
1117 struct value *parent = value_parent (toval);
1118 int offset = value_offset (parent) + value_offset (toval);
1120 gdb_byte buffer[sizeof (LONGEST)];
1123 changed_len = (value_bitpos (toval)
1124 + value_bitsize (toval)
1125 + HOST_CHAR_BIT - 1)
1128 if (changed_len > (int) sizeof (LONGEST))
1129 error (_("Can't handle bitfields which "
1130 "don't fit in a %d bit word."),
1131 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1133 if (!get_frame_register_bytes (frame, value_reg, offset,
1134 changed_len, buffer,
1138 throw_error (OPTIMIZED_OUT_ERROR,
1139 _("value has been optimized out"));
1141 throw_error (NOT_AVAILABLE_ERROR,
1142 _("value is not available"));
1145 modify_field (type, buffer, value_as_long (fromval),
1146 value_bitpos (toval), value_bitsize (toval));
1148 put_frame_register_bytes (frame, value_reg, offset,
1149 changed_len, buffer);
1153 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1156 /* If TOVAL is a special machine register requiring
1157 conversion of program values to a special raw
1159 gdbarch_value_to_register (gdbarch, frame,
1160 VALUE_REGNUM (toval), type,
1161 value_contents (fromval));
1165 put_frame_register_bytes (frame, value_reg,
1166 value_offset (toval),
1168 value_contents (fromval));
1172 observer_notify_register_changed (frame, value_reg);
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')
1830 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1832 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1833 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1835 /* Look for a match through the fields of an anonymous
1836 union, or anonymous struct. C++ provides anonymous
1839 In the GNU Chill (now deleted from GDB)
1840 implementation of variant record types, each
1841 <alternative field> has an (anonymous) union type,
1842 each member of the union represents a <variant
1843 alternative>. Each <variant alternative> is
1844 represented as a struct, with a member for each
1847 struct value *v = NULL;
1848 int new_offset = offset;
1850 /* This is pretty gross. In G++, the offset in an
1851 anonymous union is relative to the beginning of the
1852 enclosing struct. In the GNU Chill (now deleted
1853 from GDB) implementation of variant records, the
1854 bitpos is zero in an anonymous union field, so we
1855 have to add the offset of the union here. */
1856 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1857 || (TYPE_NFIELDS (field_type) > 0
1858 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1859 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1861 do_search_struct_field (name, arg1, new_offset,
1863 looking_for_baseclass, &v,
1875 for (i = 0; i < nbases; i++)
1877 struct value *v = NULL;
1878 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1879 /* If we are looking for baseclasses, this is what we get when
1880 we hit them. But it could happen that the base part's member
1881 name is not yet filled in. */
1882 int found_baseclass = (looking_for_baseclass
1883 && TYPE_BASECLASS_NAME (type, i) != NULL
1884 && (strcmp_iw (name,
1885 TYPE_BASECLASS_NAME (type,
1887 int boffset = value_embedded_offset (arg1) + offset;
1889 if (BASETYPE_VIA_VIRTUAL (type, i))
1893 boffset = baseclass_offset (type, i,
1894 value_contents_for_printing (arg1),
1895 value_embedded_offset (arg1) + offset,
1896 value_address (arg1),
1899 /* The virtual base class pointer might have been clobbered
1900 by the user program. Make sure that it still points to a
1901 valid memory location. */
1903 boffset += value_embedded_offset (arg1) + offset;
1905 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1907 CORE_ADDR base_addr;
1909 base_addr = value_address (arg1) + boffset;
1910 v2 = value_at_lazy (basetype, base_addr);
1911 if (target_read_memory (base_addr,
1912 value_contents_raw (v2),
1913 TYPE_LENGTH (value_type (v2))) != 0)
1914 error (_("virtual baseclass botch"));
1918 v2 = value_copy (arg1);
1919 deprecated_set_value_type (v2, basetype);
1920 set_value_embedded_offset (v2, boffset);
1923 if (found_baseclass)
1927 do_search_struct_field (name, v2, 0,
1928 TYPE_BASECLASS (type, i),
1929 looking_for_baseclass,
1930 result_ptr, last_boffset,
1934 else if (found_baseclass)
1935 v = value_primitive_field (arg1, offset, i, type);
1938 do_search_struct_field (name, arg1,
1939 offset + TYPE_BASECLASS_BITPOS (type,
1941 basetype, looking_for_baseclass,
1942 result_ptr, last_boffset,
1946 update_search_result (result_ptr, v, last_boffset,
1947 boffset, name, outermost_type);
1951 /* Helper function used by value_struct_elt to recurse through
1952 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1953 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1954 TYPE. If found, return value, else return NULL.
1956 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1957 fields, look for a baseclass named NAME. */
1959 static struct value *
1960 search_struct_field (const char *name, struct value *arg1, int offset,
1961 struct type *type, int looking_for_baseclass)
1963 struct value *result = NULL;
1966 do_search_struct_field (name, arg1, offset, type, looking_for_baseclass,
1967 &result, &boffset, type);
1971 /* Helper function used by value_struct_elt to recurse through
1972 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1973 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1976 If found, return value, else if name matched and args not return
1977 (value) -1, else return NULL. */
1979 static struct value *
1980 search_struct_method (const char *name, struct value **arg1p,
1981 struct value **args, int offset,
1982 int *static_memfuncp, struct type *type)
1986 int name_matched = 0;
1987 char dem_opname[64];
1989 CHECK_TYPEDEF (type);
1990 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1992 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1994 /* FIXME! May need to check for ARM demangling here. */
1995 if (startswith (t_field_name, "__") ||
1996 startswith (t_field_name, "op") ||
1997 startswith (t_field_name, "type"))
1999 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
2000 t_field_name = dem_opname;
2001 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
2002 t_field_name = dem_opname;
2004 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
2006 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
2007 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
2010 check_stub_method_group (type, i);
2011 if (j > 0 && args == 0)
2012 error (_("cannot resolve overloaded method "
2013 "`%s': no arguments supplied"), name);
2014 else if (j == 0 && args == 0)
2016 v = value_fn_field (arg1p, f, j, type, offset);
2023 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2024 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2025 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2026 TYPE_FN_FIELD_ARGS (f, j), args))
2028 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2029 return value_virtual_fn_field (arg1p, f, j,
2031 if (TYPE_FN_FIELD_STATIC_P (f, j)
2033 *static_memfuncp = 1;
2034 v = value_fn_field (arg1p, f, j, type, offset);
2043 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2048 if (BASETYPE_VIA_VIRTUAL (type, i))
2050 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2051 struct value *base_val;
2052 const gdb_byte *base_valaddr;
2054 /* The virtual base class pointer might have been
2055 clobbered by the user program. Make sure that it
2056 still points to a valid memory location. */
2058 if (offset < 0 || offset >= TYPE_LENGTH (type))
2061 struct cleanup *back_to;
2064 tmp = xmalloc (TYPE_LENGTH (baseclass));
2065 back_to = make_cleanup (xfree, tmp);
2066 address = value_address (*arg1p);
2068 if (target_read_memory (address + offset,
2069 tmp, TYPE_LENGTH (baseclass)) != 0)
2070 error (_("virtual baseclass botch"));
2072 base_val = value_from_contents_and_address (baseclass,
2075 base_valaddr = value_contents_for_printing (base_val);
2077 do_cleanups (back_to);
2082 base_valaddr = value_contents_for_printing (*arg1p);
2083 this_offset = offset;
2086 base_offset = baseclass_offset (type, i, base_valaddr,
2087 this_offset, value_address (base_val),
2092 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2094 v = search_struct_method (name, arg1p, args, base_offset + offset,
2095 static_memfuncp, TYPE_BASECLASS (type, i));
2096 if (v == (struct value *) - 1)
2102 /* FIXME-bothner: Why is this commented out? Why is it here? */
2103 /* *arg1p = arg1_tmp; */
2108 return (struct value *) - 1;
2113 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2114 extract the component named NAME from the ultimate target
2115 structure/union and return it as a value with its appropriate type.
2116 ERR is used in the error message if *ARGP's type is wrong.
2118 C++: ARGS is a list of argument types to aid in the selection of
2119 an appropriate method. Also, handle derived types.
2121 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2122 where the truthvalue of whether the function that was resolved was
2123 a static member function or not is stored.
2125 ERR is an error message to be printed in case the field is not
2129 value_struct_elt (struct value **argp, struct value **args,
2130 const char *name, int *static_memfuncp, const char *err)
2135 *argp = coerce_array (*argp);
2137 t = check_typedef (value_type (*argp));
2139 /* Follow pointers until we get to a non-pointer. */
2141 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2143 *argp = value_ind (*argp);
2144 /* Don't coerce fn pointer to fn and then back again! */
2145 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2146 *argp = coerce_array (*argp);
2147 t = check_typedef (value_type (*argp));
2150 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2151 && TYPE_CODE (t) != TYPE_CODE_UNION)
2152 error (_("Attempt to extract a component of a value that is not a %s."),
2155 /* Assume it's not, unless we see that it is. */
2156 if (static_memfuncp)
2157 *static_memfuncp = 0;
2161 /* if there are no arguments ...do this... */
2163 /* Try as a field first, because if we succeed, there is less
2165 v = search_struct_field (name, *argp, 0, t, 0);
2169 /* C++: If it was not found as a data field, then try to
2170 return it as a pointer to a method. */
2171 v = search_struct_method (name, argp, args, 0,
2172 static_memfuncp, t);
2174 if (v == (struct value *) - 1)
2175 error (_("Cannot take address of method %s."), name);
2178 if (TYPE_NFN_FIELDS (t))
2179 error (_("There is no member or method named %s."), name);
2181 error (_("There is no member named %s."), name);
2186 v = search_struct_method (name, argp, args, 0,
2187 static_memfuncp, t);
2189 if (v == (struct value *) - 1)
2191 error (_("One of the arguments you tried to pass to %s could not "
2192 "be converted to what the function wants."), name);
2196 /* See if user tried to invoke data as function. If so, hand it
2197 back. If it's not callable (i.e., a pointer to function),
2198 gdb should give an error. */
2199 v = search_struct_field (name, *argp, 0, t, 0);
2200 /* If we found an ordinary field, then it is not a method call.
2201 So, treat it as if it were a static member function. */
2202 if (v && static_memfuncp)
2203 *static_memfuncp = 1;
2207 throw_error (NOT_FOUND_ERROR,
2208 _("Structure has no component named %s."), name);
2212 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2213 to a structure or union, extract and return its component (field) of
2214 type FTYPE at the specified BITPOS.
2215 Throw an exception on error. */
2218 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2226 *argp = coerce_array (*argp);
2228 t = check_typedef (value_type (*argp));
2230 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2232 *argp = value_ind (*argp);
2233 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2234 *argp = coerce_array (*argp);
2235 t = check_typedef (value_type (*argp));
2238 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2239 && TYPE_CODE (t) != TYPE_CODE_UNION)
2240 error (_("Attempt to extract a component of a value that is not a %s."),
2243 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2245 if (!field_is_static (&TYPE_FIELD (t, i))
2246 && bitpos == TYPE_FIELD_BITPOS (t, i)
2247 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2248 return value_primitive_field (*argp, 0, i, t);
2251 error (_("No field with matching bitpos and type."));
2257 /* Search through the methods of an object (and its bases) to find a
2258 specified method. Return the pointer to the fn_field list FN_LIST of
2259 overloaded instances defined in the source language. If available
2260 and matching, a vector of matching xmethods defined in extension
2261 languages are also returned in XM_WORKER_VEC
2263 Helper function for value_find_oload_list.
2264 ARGP is a pointer to a pointer to a value (the object).
2265 METHOD is a string containing the method name.
2266 OFFSET is the offset within the value.
2267 TYPE is the assumed type of the object.
2268 FN_LIST is the pointer to matching overloaded instances defined in
2269 source language. Since this is a recursive function, *FN_LIST
2270 should be set to NULL when calling this function.
2271 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2272 0 when calling this function.
2273 XM_WORKER_VEC is the vector of matching xmethod workers. *XM_WORKER_VEC
2274 should also be set to NULL when calling this function.
2275 BASETYPE is set to the actual type of the subobject where the
2277 BOFFSET is the offset of the base subobject where the method is found. */
2280 find_method_list (struct value **argp, const char *method,
2281 int offset, struct type *type,
2282 struct fn_field **fn_list, int *num_fns,
2283 VEC (xmethod_worker_ptr) **xm_worker_vec,
2284 struct type **basetype, int *boffset)
2287 struct fn_field *f = NULL;
2288 VEC (xmethod_worker_ptr) *worker_vec = NULL, *new_vec = NULL;
2290 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2291 CHECK_TYPEDEF (type);
2293 /* First check in object itself.
2294 This function is called recursively to search through base classes.
2295 If there is a source method match found at some stage, then we need not
2296 look for source methods in consequent recursive calls. */
2297 if ((*fn_list) == NULL)
2299 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2301 /* pai: FIXME What about operators and type conversions? */
2302 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2304 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2306 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2307 f = TYPE_FN_FIELDLIST1 (type, i);
2314 /* Resolve any stub methods. */
2315 check_stub_method_group (type, i);
2322 /* Unlike source methods, xmethods can be accumulated over successive
2323 recursive calls. In other words, an xmethod named 'm' in a class
2324 will not hide an xmethod named 'm' in its base class(es). We want
2325 it to be this way because xmethods are after all convenience functions
2326 and hence there is no point restricting them with something like method
2327 hiding. Moreover, if hiding is done for xmethods as well, then we will
2328 have to provide a mechanism to un-hide (like the 'using' construct). */
2329 worker_vec = get_matching_xmethod_workers (type, method);
2330 new_vec = VEC_merge (xmethod_worker_ptr, *xm_worker_vec, worker_vec);
2332 VEC_free (xmethod_worker_ptr, *xm_worker_vec);
2333 VEC_free (xmethod_worker_ptr, worker_vec);
2334 *xm_worker_vec = new_vec;
2336 /* If source methods are not found in current class, look for them in the
2337 base classes. We also have to go through the base classes to gather
2338 extension methods. */
2339 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2343 if (BASETYPE_VIA_VIRTUAL (type, i))
2345 base_offset = baseclass_offset (type, i,
2346 value_contents_for_printing (*argp),
2347 value_offset (*argp) + offset,
2348 value_address (*argp), *argp);
2350 else /* Non-virtual base, simply use bit position from debug
2353 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2356 find_method_list (argp, method, base_offset + offset,
2357 TYPE_BASECLASS (type, i), fn_list, num_fns,
2358 xm_worker_vec, basetype, boffset);
2362 /* Return the list of overloaded methods of a specified name. The methods
2363 could be those GDB finds in the binary, or xmethod. Methods found in
2364 the binary are returned in FN_LIST, and xmethods are returned in
2367 ARGP is a pointer to a pointer to a value (the object).
2368 METHOD is the method name.
2369 OFFSET is the offset within the value contents.
2370 FN_LIST is the pointer to matching overloaded instances defined in
2372 NUM_FNS is the number of overloaded instances.
2373 XM_WORKER_VEC is the vector of matching xmethod workers defined in
2374 extension languages.
2375 BASETYPE is set to the type of the base subobject that defines the
2377 BOFFSET is the offset of the base subobject which defines the method. */
2380 value_find_oload_method_list (struct value **argp, const char *method,
2381 int offset, struct fn_field **fn_list,
2383 VEC (xmethod_worker_ptr) **xm_worker_vec,
2384 struct type **basetype, int *boffset)
2388 t = check_typedef (value_type (*argp));
2390 /* Code snarfed from value_struct_elt. */
2391 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2393 *argp = value_ind (*argp);
2394 /* Don't coerce fn pointer to fn and then back again! */
2395 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2396 *argp = coerce_array (*argp);
2397 t = check_typedef (value_type (*argp));
2400 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2401 && TYPE_CODE (t) != TYPE_CODE_UNION)
2402 error (_("Attempt to extract a component of a "
2403 "value that is not a struct or union"));
2405 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2407 /* Clear the lists. */
2410 *xm_worker_vec = NULL;
2412 find_method_list (argp, method, 0, t, fn_list, num_fns, xm_worker_vec,
2416 /* Given an array of arguments (ARGS) (which includes an
2417 entry for "this" in the case of C++ methods), the number of
2418 arguments NARGS, the NAME of a function, and whether it's a method or
2419 not (METHOD), find the best function that matches on the argument types
2420 according to the overload resolution rules.
2422 METHOD can be one of three values:
2423 NON_METHOD for non-member functions.
2424 METHOD: for member functions.
2425 BOTH: used for overload resolution of operators where the
2426 candidates are expected to be either member or non member
2427 functions. In this case the first argument ARGTYPES
2428 (representing 'this') is expected to be a reference to the
2429 target object, and will be dereferenced when attempting the
2432 In the case of class methods, the parameter OBJ is an object value
2433 in which to search for overloaded methods.
2435 In the case of non-method functions, the parameter FSYM is a symbol
2436 corresponding to one of the overloaded functions.
2438 Return value is an integer: 0 -> good match, 10 -> debugger applied
2439 non-standard coercions, 100 -> incompatible.
2441 If a method is being searched for, VALP will hold the value.
2442 If a non-method is being searched for, SYMP will hold the symbol
2445 If a method is being searched for, and it is a static method,
2446 then STATICP will point to a non-zero value.
2448 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2449 ADL overload candidates when performing overload resolution for a fully
2452 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2453 read while picking the best overload match (it may be all zeroes and thus
2454 not have a vtable pointer), in which case skip virtual function lookup.
2455 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2458 Note: This function does *not* check the value of
2459 overload_resolution. Caller must check it to see whether overload
2460 resolution is permitted. */
2463 find_overload_match (struct value **args, int nargs,
2464 const char *name, enum oload_search_type method,
2465 struct value **objp, struct symbol *fsym,
2466 struct value **valp, struct symbol **symp,
2467 int *staticp, const int no_adl,
2468 const enum noside noside)
2470 struct value *obj = (objp ? *objp : NULL);
2471 struct type *obj_type = obj ? value_type (obj) : NULL;
2472 /* Index of best overloaded function. */
2473 int func_oload_champ = -1;
2474 int method_oload_champ = -1;
2475 int src_method_oload_champ = -1;
2476 int ext_method_oload_champ = -1;
2477 int src_and_ext_equal = 0;
2479 /* The measure for the current best match. */
2480 struct badness_vector *method_badness = NULL;
2481 struct badness_vector *func_badness = NULL;
2482 struct badness_vector *ext_method_badness = NULL;
2483 struct badness_vector *src_method_badness = NULL;
2485 struct value *temp = obj;
2486 /* For methods, the list of overloaded methods. */
2487 struct fn_field *fns_ptr = NULL;
2488 /* For non-methods, the list of overloaded function symbols. */
2489 struct symbol **oload_syms = NULL;
2490 /* For xmethods, the VEC of xmethod workers. */
2491 VEC (xmethod_worker_ptr) *xm_worker_vec = NULL;
2492 /* Number of overloaded instances being considered. */
2494 struct type *basetype = NULL;
2497 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2499 const char *obj_type_name = NULL;
2500 const char *func_name = NULL;
2501 enum oload_classification match_quality;
2502 enum oload_classification method_match_quality = INCOMPATIBLE;
2503 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2504 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2505 enum oload_classification func_match_quality = INCOMPATIBLE;
2507 /* Get the list of overloaded methods or functions. */
2508 if (method == METHOD || method == BOTH)
2512 /* OBJ may be a pointer value rather than the object itself. */
2513 obj = coerce_ref (obj);
2514 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2515 obj = coerce_ref (value_ind (obj));
2516 obj_type_name = TYPE_NAME (value_type (obj));
2518 /* First check whether this is a data member, e.g. a pointer to
2520 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2522 *valp = search_struct_field (name, obj, 0,
2523 check_typedef (value_type (obj)), 0);
2527 do_cleanups (all_cleanups);
2532 /* Retrieve the list of methods with the name NAME. */
2533 value_find_oload_method_list (&temp, name, 0, &fns_ptr, &num_fns,
2534 &xm_worker_vec, &basetype, &boffset);
2535 /* If this is a method only search, and no methods were found
2536 the search has faild. */
2537 if (method == METHOD && (!fns_ptr || !num_fns) && !xm_worker_vec)
2538 error (_("Couldn't find method %s%s%s"),
2540 (obj_type_name && *obj_type_name) ? "::" : "",
2542 /* If we are dealing with stub method types, they should have
2543 been resolved by find_method_list via
2544 value_find_oload_method_list above. */
2547 gdb_assert (TYPE_SELF_TYPE (fns_ptr[0].type) != NULL);
2549 src_method_oload_champ = find_oload_champ (args, nargs,
2550 num_fns, fns_ptr, NULL,
2551 NULL, &src_method_badness);
2553 src_method_match_quality = classify_oload_match
2554 (src_method_badness, nargs,
2555 oload_method_static_p (fns_ptr, src_method_oload_champ));
2557 make_cleanup (xfree, src_method_badness);
2560 if (VEC_length (xmethod_worker_ptr, xm_worker_vec) > 0)
2562 ext_method_oload_champ = find_oload_champ (args, nargs,
2563 0, NULL, xm_worker_vec,
2564 NULL, &ext_method_badness);
2565 ext_method_match_quality = classify_oload_match (ext_method_badness,
2567 make_cleanup (xfree, ext_method_badness);
2568 make_cleanup (free_xmethod_worker_vec, xm_worker_vec);
2571 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2573 switch (compare_badness (ext_method_badness, src_method_badness))
2575 case 0: /* Src method and xmethod are equally good. */
2576 src_and_ext_equal = 1;
2577 /* If src method and xmethod are equally good, then
2578 xmethod should be the winner. Hence, fall through to the
2579 case where a xmethod is better than the source
2580 method, except when the xmethod match quality is
2583 case 1: /* Src method and ext method are incompatible. */
2584 /* If ext method match is not standard, then let source method
2585 win. Otherwise, fallthrough to let xmethod win. */
2586 if (ext_method_match_quality != STANDARD)
2588 method_oload_champ = src_method_oload_champ;
2589 method_badness = src_method_badness;
2590 ext_method_oload_champ = -1;
2591 method_match_quality = src_method_match_quality;
2595 case 2: /* Ext method is champion. */
2596 method_oload_champ = ext_method_oload_champ;
2597 method_badness = ext_method_badness;
2598 src_method_oload_champ = -1;
2599 method_match_quality = ext_method_match_quality;
2601 case 3: /* Src method is champion. */
2602 method_oload_champ = src_method_oload_champ;
2603 method_badness = src_method_badness;
2604 ext_method_oload_champ = -1;
2605 method_match_quality = src_method_match_quality;
2608 gdb_assert_not_reached ("Unexpected overload comparison "
2613 else if (src_method_oload_champ >= 0)
2615 method_oload_champ = src_method_oload_champ;
2616 method_badness = src_method_badness;
2617 method_match_quality = src_method_match_quality;
2619 else if (ext_method_oload_champ >= 0)
2621 method_oload_champ = ext_method_oload_champ;
2622 method_badness = ext_method_badness;
2623 method_match_quality = ext_method_match_quality;
2627 if (method == NON_METHOD || method == BOTH)
2629 const char *qualified_name = NULL;
2631 /* If the overload match is being search for both as a method
2632 and non member function, the first argument must now be
2635 args[0] = value_ind (args[0]);
2639 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2641 /* If we have a function with a C++ name, try to extract just
2642 the function part. Do not try this for non-functions (e.g.
2643 function pointers). */
2645 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2650 temp = cp_func_name (qualified_name);
2652 /* If cp_func_name did not remove anything, the name of the
2653 symbol did not include scope or argument types - it was
2654 probably a C-style function. */
2657 make_cleanup (xfree, temp);
2658 if (strcmp (temp, qualified_name) == 0)
2668 qualified_name = name;
2671 /* If there was no C++ name, this must be a C-style function or
2672 not a function at all. Just return the same symbol. Do the
2673 same if cp_func_name fails for some reason. */
2674 if (func_name == NULL)
2677 do_cleanups (all_cleanups);
2681 func_oload_champ = find_oload_champ_namespace (args, nargs,
2688 if (func_oload_champ >= 0)
2689 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2691 make_cleanup (xfree, oload_syms);
2692 make_cleanup (xfree, func_badness);
2695 /* Did we find a match ? */
2696 if (method_oload_champ == -1 && func_oload_champ == -1)
2697 throw_error (NOT_FOUND_ERROR,
2698 _("No symbol \"%s\" in current context."),
2701 /* If we have found both a method match and a function
2702 match, find out which one is better, and calculate match
2704 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2706 switch (compare_badness (func_badness, method_badness))
2708 case 0: /* Top two contenders are equally good. */
2709 /* FIXME: GDB does not support the general ambiguous case.
2710 All candidates should be collected and presented the
2712 error (_("Ambiguous overload resolution"));
2714 case 1: /* Incomparable top contenders. */
2715 /* This is an error incompatible candidates
2716 should not have been proposed. */
2717 error (_("Internal error: incompatible "
2718 "overload candidates proposed"));
2720 case 2: /* Function champion. */
2721 method_oload_champ = -1;
2722 match_quality = func_match_quality;
2724 case 3: /* Method champion. */
2725 func_oload_champ = -1;
2726 match_quality = method_match_quality;
2729 error (_("Internal error: unexpected overload comparison result"));
2735 /* We have either a method match or a function match. */
2736 if (method_oload_champ >= 0)
2737 match_quality = method_match_quality;
2739 match_quality = func_match_quality;
2742 if (match_quality == INCOMPATIBLE)
2744 if (method == METHOD)
2745 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2747 (obj_type_name && *obj_type_name) ? "::" : "",
2750 error (_("Cannot resolve function %s to any overloaded instance"),
2753 else if (match_quality == NON_STANDARD)
2755 if (method == METHOD)
2756 warning (_("Using non-standard conversion to match "
2757 "method %s%s%s to supplied arguments"),
2759 (obj_type_name && *obj_type_name) ? "::" : "",
2762 warning (_("Using non-standard conversion to match "
2763 "function %s to supplied arguments"),
2767 if (staticp != NULL)
2768 *staticp = oload_method_static_p (fns_ptr, method_oload_champ);
2770 if (method_oload_champ >= 0)
2772 if (src_method_oload_champ >= 0)
2774 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)
2775 && noside != EVAL_AVOID_SIDE_EFFECTS)
2777 *valp = value_virtual_fn_field (&temp, fns_ptr,
2778 method_oload_champ, basetype,
2782 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2787 *valp = value_of_xmethod (clone_xmethod_worker
2788 (VEC_index (xmethod_worker_ptr, xm_worker_vec,
2789 ext_method_oload_champ)));
2793 *symp = oload_syms[func_oload_champ];
2797 struct type *temp_type = check_typedef (value_type (temp));
2798 struct type *objtype = check_typedef (obj_type);
2800 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2801 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2802 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2804 temp = value_addr (temp);
2809 do_cleanups (all_cleanups);
2811 switch (match_quality)
2817 default: /* STANDARD */
2822 /* Find the best overload match, searching for FUNC_NAME in namespaces
2823 contained in QUALIFIED_NAME until it either finds a good match or
2824 runs out of namespaces. It stores the overloaded functions in
2825 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2826 calling function is responsible for freeing *OLOAD_SYMS and
2827 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2831 find_oload_champ_namespace (struct value **args, int nargs,
2832 const char *func_name,
2833 const char *qualified_name,
2834 struct symbol ***oload_syms,
2835 struct badness_vector **oload_champ_bv,
2840 find_oload_champ_namespace_loop (args, nargs,
2843 oload_syms, oload_champ_bv,
2850 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2851 how deep we've looked for namespaces, and the champ is stored in
2852 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2853 if it isn't. Other arguments are the same as in
2854 find_oload_champ_namespace
2856 It is the caller's responsibility to free *OLOAD_SYMS and
2860 find_oload_champ_namespace_loop (struct value **args, int nargs,
2861 const char *func_name,
2862 const char *qualified_name,
2864 struct symbol ***oload_syms,
2865 struct badness_vector **oload_champ_bv,
2869 int next_namespace_len = namespace_len;
2870 int searched_deeper = 0;
2872 struct cleanup *old_cleanups;
2873 int new_oload_champ;
2874 struct symbol **new_oload_syms;
2875 struct badness_vector *new_oload_champ_bv;
2876 char *new_namespace;
2878 if (next_namespace_len != 0)
2880 gdb_assert (qualified_name[next_namespace_len] == ':');
2881 next_namespace_len += 2;
2883 next_namespace_len +=
2884 cp_find_first_component (qualified_name + next_namespace_len);
2886 /* Initialize these to values that can safely be xfree'd. */
2888 *oload_champ_bv = NULL;
2890 /* First, see if we have a deeper namespace we can search in.
2891 If we get a good match there, use it. */
2893 if (qualified_name[next_namespace_len] == ':')
2895 searched_deeper = 1;
2897 if (find_oload_champ_namespace_loop (args, nargs,
2898 func_name, qualified_name,
2900 oload_syms, oload_champ_bv,
2901 oload_champ, no_adl))
2907 /* If we reach here, either we're in the deepest namespace or we
2908 didn't find a good match in a deeper namespace. But, in the
2909 latter case, we still have a bad match in a deeper namespace;
2910 note that we might not find any match at all in the current
2911 namespace. (There's always a match in the deepest namespace,
2912 because this overload mechanism only gets called if there's a
2913 function symbol to start off with.) */
2915 old_cleanups = make_cleanup (xfree, *oload_syms);
2916 make_cleanup (xfree, *oload_champ_bv);
2917 new_namespace = alloca (namespace_len + 1);
2918 strncpy (new_namespace, qualified_name, namespace_len);
2919 new_namespace[namespace_len] = '\0';
2920 new_oload_syms = make_symbol_overload_list (func_name,
2923 /* If we have reached the deepest level perform argument
2924 determined lookup. */
2925 if (!searched_deeper && !no_adl)
2928 struct type **arg_types;
2930 /* Prepare list of argument types for overload resolution. */
2931 arg_types = (struct type **)
2932 alloca (nargs * (sizeof (struct type *)));
2933 for (ix = 0; ix < nargs; ix++)
2934 arg_types[ix] = value_type (args[ix]);
2935 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2938 while (new_oload_syms[num_fns])
2941 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2942 NULL, NULL, new_oload_syms,
2943 &new_oload_champ_bv);
2945 /* Case 1: We found a good match. Free earlier matches (if any),
2946 and return it. Case 2: We didn't find a good match, but we're
2947 not the deepest function. Then go with the bad match that the
2948 deeper function found. Case 3: We found a bad match, and we're
2949 the deepest function. Then return what we found, even though
2950 it's a bad match. */
2952 if (new_oload_champ != -1
2953 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2955 *oload_syms = new_oload_syms;
2956 *oload_champ = new_oload_champ;
2957 *oload_champ_bv = new_oload_champ_bv;
2958 do_cleanups (old_cleanups);
2961 else if (searched_deeper)
2963 xfree (new_oload_syms);
2964 xfree (new_oload_champ_bv);
2965 discard_cleanups (old_cleanups);
2970 *oload_syms = new_oload_syms;
2971 *oload_champ = new_oload_champ;
2972 *oload_champ_bv = new_oload_champ_bv;
2973 do_cleanups (old_cleanups);
2978 /* Look for a function to take NARGS args of ARGS. Find
2979 the best match from among the overloaded methods or functions
2980 given by FNS_PTR or OLOAD_SYMS or XM_WORKER_VEC, respectively.
2981 One, and only one of FNS_PTR, OLOAD_SYMS and XM_WORKER_VEC can be
2984 If XM_WORKER_VEC is NULL, then the length of the arrays FNS_PTR
2985 or OLOAD_SYMS (whichever is non-NULL) is specified in NUM_FNS.
2987 Return the index of the best match; store an indication of the
2988 quality of the match in OLOAD_CHAMP_BV.
2990 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2993 find_oload_champ (struct value **args, int nargs,
2994 int num_fns, struct fn_field *fns_ptr,
2995 VEC (xmethod_worker_ptr) *xm_worker_vec,
2996 struct symbol **oload_syms,
2997 struct badness_vector **oload_champ_bv)
3001 int xm_worker_vec_n = VEC_length (xmethod_worker_ptr, xm_worker_vec);
3002 /* A measure of how good an overloaded instance is. */
3003 struct badness_vector *bv;
3004 /* Index of best overloaded function. */
3005 int oload_champ = -1;
3006 /* Current ambiguity state for overload resolution. */
3007 int oload_ambiguous = 0;
3008 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
3010 /* A champion can be found among methods alone, or among functions
3011 alone, or in xmethods alone, but not in more than one of these
3013 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) + (xm_worker_vec != NULL)
3016 *oload_champ_bv = NULL;
3018 fn_count = (xm_worker_vec != NULL
3019 ? VEC_length (xmethod_worker_ptr, xm_worker_vec)
3021 /* Consider each candidate in turn. */
3022 for (ix = 0; ix < fn_count; ix++)
3025 int static_offset = 0;
3027 struct type **parm_types;
3028 struct xmethod_worker *worker = NULL;
3030 if (xm_worker_vec != NULL)
3032 worker = VEC_index (xmethod_worker_ptr, xm_worker_vec, ix);
3033 parm_types = get_xmethod_arg_types (worker, &nparms);
3037 if (fns_ptr != NULL)
3039 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
3040 static_offset = oload_method_static_p (fns_ptr, ix);
3043 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
3045 parm_types = (struct type **)
3046 xmalloc (nparms * (sizeof (struct type *)));
3047 for (jj = 0; jj < nparms; jj++)
3048 parm_types[jj] = (fns_ptr != NULL
3049 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
3050 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
3054 /* Compare parameter types to supplied argument types. Skip
3055 THIS for static methods. */
3056 bv = rank_function (parm_types, nparms,
3057 args + static_offset,
3058 nargs - static_offset);
3060 if (!*oload_champ_bv)
3062 *oload_champ_bv = bv;
3065 else /* See whether current candidate is better or worse than
3067 switch (compare_badness (bv, *oload_champ_bv))
3069 case 0: /* Top two contenders are equally good. */
3070 oload_ambiguous = 1;
3072 case 1: /* Incomparable top contenders. */
3073 oload_ambiguous = 2;
3075 case 2: /* New champion, record details. */
3076 *oload_champ_bv = bv;
3077 oload_ambiguous = 0;
3087 if (fns_ptr != NULL)
3088 fprintf_filtered (gdb_stderr,
3089 "Overloaded method instance %s, # of parms %d\n",
3090 fns_ptr[ix].physname, nparms);
3091 else if (xm_worker_vec != NULL)
3092 fprintf_filtered (gdb_stderr,
3093 "Xmethod worker, # of parms %d\n",
3096 fprintf_filtered (gdb_stderr,
3097 "Overloaded function instance "
3098 "%s # of parms %d\n",
3099 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3101 for (jj = 0; jj < nargs - static_offset; jj++)
3102 fprintf_filtered (gdb_stderr,
3103 "...Badness @ %d : %d\n",
3104 jj, bv->rank[jj].rank);
3105 fprintf_filtered (gdb_stderr, "Overload resolution "
3106 "champion is %d, ambiguous? %d\n",
3107 oload_champ, oload_ambiguous);
3114 /* Return 1 if we're looking at a static method, 0 if we're looking at
3115 a non-static method or a function that isn't a method. */
3118 oload_method_static_p (struct fn_field *fns_ptr, int index)
3120 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3126 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3128 static enum oload_classification
3129 classify_oload_match (struct badness_vector *oload_champ_bv,
3134 enum oload_classification worst = STANDARD;
3136 for (ix = 1; ix <= nargs - static_offset; ix++)
3138 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3139 or worse return INCOMPATIBLE. */
3140 if (compare_ranks (oload_champ_bv->rank[ix],
3141 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3142 return INCOMPATIBLE; /* Truly mismatched types. */
3143 /* Otherwise If this conversion is as bad as
3144 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3145 else if (compare_ranks (oload_champ_bv->rank[ix],
3146 NS_POINTER_CONVERSION_BADNESS) <= 0)
3147 worst = NON_STANDARD; /* Non-standard type conversions
3151 /* If no INCOMPATIBLE classification was found, return the worst one
3152 that was found (if any). */
3156 /* C++: return 1 is NAME is a legitimate name for the destructor of
3157 type TYPE. If TYPE does not have a destructor, or if NAME is
3158 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3159 have CHECK_TYPEDEF applied, this function will apply it itself. */
3162 destructor_name_p (const char *name, struct type *type)
3166 const char *dname = type_name_no_tag_or_error (type);
3167 const char *cp = strchr (dname, '<');
3170 /* Do not compare the template part for template classes. */
3172 len = strlen (dname);
3175 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3176 error (_("name of destructor must equal name of class"));
3183 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3184 class". If the name is found, return a value representing it;
3185 otherwise throw an exception. */
3187 static struct value *
3188 enum_constant_from_type (struct type *type, const char *name)
3191 int name_len = strlen (name);
3193 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3194 && TYPE_DECLARED_CLASS (type));
3196 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3198 const char *fname = TYPE_FIELD_NAME (type, i);
3201 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3205 /* Look for the trailing "::NAME", since enum class constant
3206 names are qualified here. */
3207 len = strlen (fname);
3208 if (len + 2 >= name_len
3209 && fname[len - name_len - 2] == ':'
3210 && fname[len - name_len - 1] == ':'
3211 && strcmp (&fname[len - name_len], name) == 0)
3212 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3215 error (_("no constant named \"%s\" in enum \"%s\""),
3216 name, TYPE_TAG_NAME (type));
3219 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3220 return the appropriate member (or the address of the member, if
3221 WANT_ADDRESS). This function is used to resolve user expressions
3222 of the form "DOMAIN::NAME". For more details on what happens, see
3223 the comment before value_struct_elt_for_reference. */
3226 value_aggregate_elt (struct type *curtype, const char *name,
3227 struct type *expect_type, int want_address,
3230 switch (TYPE_CODE (curtype))
3232 case TYPE_CODE_STRUCT:
3233 case TYPE_CODE_UNION:
3234 return value_struct_elt_for_reference (curtype, 0, curtype,
3236 want_address, noside);
3237 case TYPE_CODE_NAMESPACE:
3238 return value_namespace_elt (curtype, name,
3239 want_address, noside);
3241 case TYPE_CODE_ENUM:
3242 return enum_constant_from_type (curtype, name);
3245 internal_error (__FILE__, __LINE__,
3246 _("non-aggregate type in value_aggregate_elt"));
3250 /* Compares the two method/function types T1 and T2 for "equality"
3251 with respect to the methods' parameters. If the types of the
3252 two parameter lists are the same, returns 1; 0 otherwise. This
3253 comparison may ignore any artificial parameters in T1 if
3254 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3255 the first artificial parameter in T1, assumed to be a 'this' pointer.
3257 The type T2 is expected to have come from make_params (in eval.c). */
3260 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3264 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3267 /* If skipping artificial fields, find the first real field
3269 if (skip_artificial)
3271 while (start < TYPE_NFIELDS (t1)
3272 && TYPE_FIELD_ARTIFICIAL (t1, start))
3276 /* Now compare parameters. */
3278 /* Special case: a method taking void. T1 will contain no
3279 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3280 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3281 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3284 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3288 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3290 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3291 TYPE_FIELD_TYPE (t2, i), NULL),
3292 EXACT_MATCH_BADNESS) != 0)
3302 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3303 return the address of this member as a "pointer to member" type.
3304 If INTYPE is non-null, then it will be the type of the member we
3305 are looking for. This will help us resolve "pointers to member
3306 functions". This function is used to resolve user expressions of
3307 the form "DOMAIN::NAME". */
3309 static struct value *
3310 value_struct_elt_for_reference (struct type *domain, int offset,
3311 struct type *curtype, const char *name,
3312 struct type *intype,
3316 struct type *t = curtype;
3318 struct value *v, *result;
3320 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3321 && TYPE_CODE (t) != TYPE_CODE_UNION)
3322 error (_("Internal error: non-aggregate type "
3323 "to value_struct_elt_for_reference"));
3325 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3327 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3329 if (t_field_name && strcmp (t_field_name, name) == 0)
3331 if (field_is_static (&TYPE_FIELD (t, i)))
3333 v = value_static_field (t, i);
3338 if (TYPE_FIELD_PACKED (t, i))
3339 error (_("pointers to bitfield members not allowed"));
3342 return value_from_longest
3343 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3344 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3345 else if (noside != EVAL_NORMAL)
3346 return allocate_value (TYPE_FIELD_TYPE (t, i));
3349 /* Try to evaluate NAME as a qualified name with implicit
3350 this pointer. In this case, attempt to return the
3351 equivalent to `this->*(&TYPE::NAME)'. */
3352 v = value_of_this_silent (current_language);
3357 struct type *type, *tmp;
3359 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3360 type = check_typedef (value_type (ptr));
3361 gdb_assert (type != NULL
3362 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3363 tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
3364 v = value_cast_pointers (tmp, v, 1);
3365 mem_offset = value_as_long (ptr);
3366 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3367 result = value_from_pointer (tmp,
3368 value_as_long (v) + mem_offset);
3369 return value_ind (result);
3372 error (_("Cannot reference non-static field \"%s\""), name);
3377 /* C++: If it was not found as a data field, then try to return it
3378 as a pointer to a method. */
3380 /* Perform all necessary dereferencing. */
3381 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3382 intype = TYPE_TARGET_TYPE (intype);
3384 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3386 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3387 char dem_opname[64];
3389 if (startswith (t_field_name, "__")
3390 || startswith (t_field_name, "op")
3391 || startswith (t_field_name, "type"))
3393 if (cplus_demangle_opname (t_field_name,
3394 dem_opname, DMGL_ANSI))
3395 t_field_name = dem_opname;
3396 else if (cplus_demangle_opname (t_field_name,
3398 t_field_name = dem_opname;
3400 if (t_field_name && strcmp (t_field_name, name) == 0)
3403 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3404 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3406 check_stub_method_group (t, i);
3410 for (j = 0; j < len; ++j)
3412 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3413 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3419 error (_("no member function matches "
3420 "that type instantiation"));
3427 for (ii = 0; ii < len; ++ii)
3429 /* Skip artificial methods. This is necessary if,
3430 for example, the user wants to "print
3431 subclass::subclass" with only one user-defined
3432 constructor. There is no ambiguity in this case.
3433 We are careful here to allow artificial methods
3434 if they are the unique result. */
3435 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3442 /* Desired method is ambiguous if more than one
3443 method is defined. */
3444 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3445 error (_("non-unique member `%s' requires "
3446 "type instantiation"), name);
3452 error (_("no matching member function"));
3455 if (TYPE_FN_FIELD_STATIC_P (f, j))
3458 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3465 return value_addr (read_var_value (s, 0));
3467 return read_var_value (s, 0);
3470 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3474 result = allocate_value
3475 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3476 cplus_make_method_ptr (value_type (result),
3477 value_contents_writeable (result),
3478 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3480 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3481 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3483 error (_("Cannot reference virtual member function \"%s\""),
3489 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3495 v = read_var_value (s, 0);
3500 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3501 cplus_make_method_ptr (value_type (result),
3502 value_contents_writeable (result),
3503 value_address (v), 0);
3509 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3514 if (BASETYPE_VIA_VIRTUAL (t, i))
3517 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3518 v = value_struct_elt_for_reference (domain,
3519 offset + base_offset,
3520 TYPE_BASECLASS (t, i),
3522 want_address, noside);
3527 /* As a last chance, pretend that CURTYPE is a namespace, and look
3528 it up that way; this (frequently) works for types nested inside
3531 return value_maybe_namespace_elt (curtype, name,
3532 want_address, noside);
3535 /* C++: Return the member NAME of the namespace given by the type
3538 static struct value *
3539 value_namespace_elt (const struct type *curtype,
3540 const char *name, int want_address,
3543 struct value *retval = value_maybe_namespace_elt (curtype, name,
3548 error (_("No symbol \"%s\" in namespace \"%s\"."),
3549 name, TYPE_TAG_NAME (curtype));
3554 /* A helper function used by value_namespace_elt and
3555 value_struct_elt_for_reference. It looks up NAME inside the
3556 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3557 is a class and NAME refers to a type in CURTYPE itself (as opposed
3558 to, say, some base class of CURTYPE). */
3560 static struct value *
3561 value_maybe_namespace_elt (const struct type *curtype,
3562 const char *name, int want_address,
3565 const char *namespace_name = TYPE_TAG_NAME (curtype);
3567 struct value *result;
3569 sym = cp_lookup_symbol_namespace (namespace_name, name,
3570 get_selected_block (0), VAR_DOMAIN);
3574 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3575 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))
3576 result = allocate_value (SYMBOL_TYPE (sym));
3578 result = value_of_variable (sym, get_selected_block (0));
3581 result = value_addr (result);
3586 /* Given a pointer or a reference value V, find its real (RTTI) type.
3588 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3589 and refer to the values computed for the object pointed to. */
3592 value_rtti_indirect_type (struct value *v, int *full,
3593 int *top, int *using_enc)
3595 struct value *target = NULL;
3596 struct type *type, *real_type, *target_type;
3598 type = value_type (v);
3599 type = check_typedef (type);
3600 if (TYPE_CODE (type) == TYPE_CODE_REF)
3601 target = coerce_ref (v);
3602 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3607 target = value_ind (v);
3609 CATCH (except, RETURN_MASK_ERROR)
3611 if (except.error == MEMORY_ERROR)
3613 /* value_ind threw a memory error. The pointer is NULL or
3614 contains an uninitialized value: we can't determine any
3618 throw_exception (except);
3625 real_type = value_rtti_type (target, full, top, using_enc);
3629 /* Copy qualifiers to the referenced object. */
3630 target_type = value_type (target);
3631 real_type = make_cv_type (TYPE_CONST (target_type),
3632 TYPE_VOLATILE (target_type), real_type, NULL);
3633 if (TYPE_CODE (type) == TYPE_CODE_REF)
3634 real_type = lookup_reference_type (real_type);
3635 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3636 real_type = lookup_pointer_type (real_type);
3638 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3640 /* Copy qualifiers to the pointer/reference. */
3641 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3648 /* Given a value pointed to by ARGP, check its real run-time type, and
3649 if that is different from the enclosing type, create a new value
3650 using the real run-time type as the enclosing type (and of the same
3651 type as ARGP) and return it, with the embedded offset adjusted to
3652 be the correct offset to the enclosed object. RTYPE is the type,
3653 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3654 by value_rtti_type(). If these are available, they can be supplied
3655 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3656 NULL if they're not available. */
3659 value_full_object (struct value *argp,
3661 int xfull, int xtop,
3664 struct type *real_type;
3668 struct value *new_val;
3675 using_enc = xusing_enc;
3678 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3680 /* If no RTTI data, or if object is already complete, do nothing. */
3681 if (!real_type || real_type == value_enclosing_type (argp))
3684 /* In a destructor we might see a real type that is a superclass of
3685 the object's type. In this case it is better to leave the object
3688 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3691 /* If we have the full object, but for some reason the enclosing
3692 type is wrong, set it. */
3693 /* pai: FIXME -- sounds iffy */
3696 argp = value_copy (argp);
3697 set_value_enclosing_type (argp, real_type);
3701 /* Check if object is in memory. */
3702 if (VALUE_LVAL (argp) != lval_memory)
3704 warning (_("Couldn't retrieve complete object of RTTI "
3705 "type %s; object may be in register(s)."),
3706 TYPE_NAME (real_type));
3711 /* All other cases -- retrieve the complete object. */
3712 /* Go back by the computed top_offset from the beginning of the
3713 object, adjusting for the embedded offset of argp if that's what
3714 value_rtti_type used for its computation. */
3715 new_val = value_at_lazy (real_type, value_address (argp) - top +
3716 (using_enc ? 0 : value_embedded_offset (argp)));
3717 deprecated_set_value_type (new_val, value_type (argp));
3718 set_value_embedded_offset (new_val, (using_enc
3719 ? top + value_embedded_offset (argp)
3725 /* Return the value of the local variable, if one exists. Throw error
3726 otherwise, such as if the request is made in an inappropriate context. */
3729 value_of_this (const struct language_defn *lang)
3732 const struct block *b;
3733 struct frame_info *frame;
3735 if (!lang->la_name_of_this)
3736 error (_("no `this' in current language"));
3738 frame = get_selected_frame (_("no frame selected"));
3740 b = get_frame_block (frame, NULL);
3742 sym = lookup_language_this (lang, b);
3744 error (_("current stack frame does not contain a variable named `%s'"),
3745 lang->la_name_of_this);
3747 return read_var_value (sym, frame);
3750 /* Return the value of the local variable, if one exists. Return NULL
3751 otherwise. Never throw error. */
3754 value_of_this_silent (const struct language_defn *lang)
3756 struct value *ret = NULL;
3760 ret = value_of_this (lang);
3762 CATCH (except, RETURN_MASK_ERROR)
3770 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3771 elements long, starting at LOWBOUND. The result has the same lower
3772 bound as the original ARRAY. */
3775 value_slice (struct value *array, int lowbound, int length)
3777 struct type *slice_range_type, *slice_type, *range_type;
3778 LONGEST lowerbound, upperbound;
3779 struct value *slice;
3780 struct type *array_type;
3782 array_type = check_typedef (value_type (array));
3783 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3784 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3785 error (_("cannot take slice of non-array"));
3787 range_type = TYPE_INDEX_TYPE (array_type);
3788 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3789 error (_("slice from bad array or bitstring"));
3791 if (lowbound < lowerbound || length < 0
3792 || lowbound + length - 1 > upperbound)
3793 error (_("slice out of range"));
3795 /* FIXME-type-allocation: need a way to free this type when we are
3797 slice_range_type = create_static_range_type ((struct type *) NULL,
3798 TYPE_TARGET_TYPE (range_type),
3800 lowbound + length - 1);
3803 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3805 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3807 slice_type = create_array_type ((struct type *) NULL,
3810 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3812 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3813 slice = allocate_value_lazy (slice_type);
3816 slice = allocate_value (slice_type);
3817 value_contents_copy (slice, 0, array, offset,
3818 TYPE_LENGTH (slice_type));
3821 set_value_component_location (slice, array);
3822 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3823 set_value_offset (slice, value_offset (array) + offset);
3829 /* Create a value for a FORTRAN complex number. Currently most of the
3830 time values are coerced to COMPLEX*16 (i.e. a complex number
3831 composed of 2 doubles. This really should be a smarter routine
3832 that figures out precision inteligently as opposed to assuming
3833 doubles. FIXME: fmb */
3836 value_literal_complex (struct value *arg1,
3841 struct type *real_type = TYPE_TARGET_TYPE (type);
3843 val = allocate_value (type);
3844 arg1 = value_cast (real_type, arg1);
3845 arg2 = value_cast (real_type, arg2);
3847 memcpy (value_contents_raw (val),
3848 value_contents (arg1), TYPE_LENGTH (real_type));
3849 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3850 value_contents (arg2), TYPE_LENGTH (real_type));
3854 /* Cast a value into the appropriate complex data type. */
3856 static struct value *
3857 cast_into_complex (struct type *type, struct value *val)
3859 struct type *real_type = TYPE_TARGET_TYPE (type);
3861 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3863 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3864 struct value *re_val = allocate_value (val_real_type);
3865 struct value *im_val = allocate_value (val_real_type);
3867 memcpy (value_contents_raw (re_val),
3868 value_contents (val), TYPE_LENGTH (val_real_type));
3869 memcpy (value_contents_raw (im_val),
3870 value_contents (val) + TYPE_LENGTH (val_real_type),
3871 TYPE_LENGTH (val_real_type));
3873 return value_literal_complex (re_val, im_val, type);
3875 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3876 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3877 return value_literal_complex (val,
3878 value_zero (real_type, not_lval),
3881 error (_("cannot cast non-number to complex"));
3885 _initialize_valops (void)
3887 add_setshow_boolean_cmd ("overload-resolution", class_support,
3888 &overload_resolution, _("\
3889 Set overload resolution in evaluating C++ functions."), _("\
3890 Show overload resolution in evaluating C++ functions."),
3892 show_overload_resolution,
3893 &setlist, &showlist);
3894 overload_resolution = 1;