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 *,
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)
130 struct block_symbol sym;
132 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
133 if (sym.symbol != NULL)
135 if (SYMBOL_CLASS (sym.symbol) != LOC_BLOCK)
137 error (_("\"%s\" exists in this program but is not a function."),
142 *objf_p = symbol_objfile (sym.symbol);
144 return value_of_variable (sym.symbol, sym.block);
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, 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), 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 type = 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)
961 ULONGEST xfered_total = 0;
962 struct gdbarch *arch = get_value_arch (val);
963 int unit_size = gdbarch_addressable_memory_unit_size (arch);
965 while (xfered_total < length)
967 enum target_xfer_status status;
968 ULONGEST xfered_partial;
970 status = target_xfer_partial (current_target.beneath,
971 TARGET_OBJECT_MEMORY, NULL,
972 buffer + xfered_total * unit_size, NULL,
973 memaddr + xfered_total,
974 length - xfered_total,
977 if (status == TARGET_XFER_OK)
979 else if (status == TARGET_XFER_UNAVAILABLE)
980 mark_value_bytes_unavailable (val, embedded_offset + xfered_total,
982 else if (status == TARGET_XFER_EOF)
983 memory_error (TARGET_XFER_E_IO, memaddr + xfered_total);
985 memory_error (status, memaddr + xfered_total);
987 xfered_total += xfered_partial;
992 /* Store the contents of FROMVAL into the location of TOVAL.
993 Return a new value with the location of TOVAL and contents of FROMVAL. */
996 value_assign (struct value *toval, struct value *fromval)
1000 struct frame_id old_frame;
1002 if (!deprecated_value_modifiable (toval))
1003 error (_("Left operand of assignment is not a modifiable lvalue."));
1005 toval = coerce_ref (toval);
1007 type = value_type (toval);
1008 if (VALUE_LVAL (toval) != lval_internalvar)
1009 fromval = value_cast (type, fromval);
1012 /* Coerce arrays and functions to pointers, except for arrays
1013 which only live in GDB's storage. */
1014 if (!value_must_coerce_to_target (fromval))
1015 fromval = coerce_array (fromval);
1018 type = check_typedef (type);
1020 /* Since modifying a register can trash the frame chain, and
1021 modifying memory can trash the frame cache, we save the old frame
1022 and then restore the new frame afterwards. */
1023 old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
1025 switch (VALUE_LVAL (toval))
1027 case lval_internalvar:
1028 set_internalvar (VALUE_INTERNALVAR (toval), fromval);
1029 return value_of_internalvar (get_type_arch (type),
1030 VALUE_INTERNALVAR (toval));
1032 case lval_internalvar_component:
1034 int offset = value_offset (toval);
1036 /* Are we dealing with a bitfield?
1038 It is important to mention that `value_parent (toval)' is
1039 non-NULL iff `value_bitsize (toval)' is non-zero. */
1040 if (value_bitsize (toval))
1042 /* VALUE_INTERNALVAR below refers to the parent value, while
1043 the offset is relative to this parent value. */
1044 gdb_assert (value_parent (value_parent (toval)) == NULL);
1045 offset += value_offset (value_parent (toval));
1048 set_internalvar_component (VALUE_INTERNALVAR (toval),
1050 value_bitpos (toval),
1051 value_bitsize (toval),
1058 const gdb_byte *dest_buffer;
1059 CORE_ADDR changed_addr;
1061 gdb_byte buffer[sizeof (LONGEST)];
1063 if (value_bitsize (toval))
1065 struct value *parent = value_parent (toval);
1067 changed_addr = value_address (parent) + value_offset (toval);
1068 changed_len = (value_bitpos (toval)
1069 + value_bitsize (toval)
1070 + HOST_CHAR_BIT - 1)
1073 /* If we can read-modify-write exactly the size of the
1074 containing type (e.g. short or int) then do so. This
1075 is safer for volatile bitfields mapped to hardware
1077 if (changed_len < TYPE_LENGTH (type)
1078 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
1079 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
1080 changed_len = TYPE_LENGTH (type);
1082 if (changed_len > (int) sizeof (LONGEST))
1083 error (_("Can't handle bitfields which "
1084 "don't fit in a %d bit word."),
1085 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1087 read_memory (changed_addr, buffer, changed_len);
1088 modify_field (type, buffer, value_as_long (fromval),
1089 value_bitpos (toval), value_bitsize (toval));
1090 dest_buffer = buffer;
1094 changed_addr = value_address (toval);
1095 changed_len = type_length_units (type);
1096 dest_buffer = value_contents (fromval);
1099 write_memory_with_notification (changed_addr, dest_buffer, changed_len);
1105 struct frame_info *frame;
1106 struct gdbarch *gdbarch;
1109 /* Figure out which frame this is in currently. */
1110 frame = frame_find_by_id (VALUE_FRAME_ID (toval));
1111 value_reg = VALUE_REGNUM (toval);
1114 error (_("Value being assigned to is no longer active."));
1116 gdbarch = get_frame_arch (frame);
1118 if (value_bitsize (toval))
1120 struct value *parent = value_parent (toval);
1121 int offset = value_offset (parent) + value_offset (toval);
1123 gdb_byte buffer[sizeof (LONGEST)];
1126 changed_len = (value_bitpos (toval)
1127 + value_bitsize (toval)
1128 + HOST_CHAR_BIT - 1)
1131 if (changed_len > (int) sizeof (LONGEST))
1132 error (_("Can't handle bitfields which "
1133 "don't fit in a %d bit word."),
1134 (int) sizeof (LONGEST) * HOST_CHAR_BIT);
1136 if (!get_frame_register_bytes (frame, value_reg, offset,
1137 changed_len, buffer,
1141 throw_error (OPTIMIZED_OUT_ERROR,
1142 _("value has been optimized out"));
1144 throw_error (NOT_AVAILABLE_ERROR,
1145 _("value is not available"));
1148 modify_field (type, buffer, value_as_long (fromval),
1149 value_bitpos (toval), value_bitsize (toval));
1151 put_frame_register_bytes (frame, value_reg, offset,
1152 changed_len, buffer);
1156 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
1159 /* If TOVAL is a special machine register requiring
1160 conversion of program values to a special raw
1162 gdbarch_value_to_register (gdbarch, frame,
1163 VALUE_REGNUM (toval), type,
1164 value_contents (fromval));
1168 put_frame_register_bytes (frame, value_reg,
1169 value_offset (toval),
1171 value_contents (fromval));
1175 observer_notify_register_changed (frame, value_reg);
1181 const struct lval_funcs *funcs = value_computed_funcs (toval);
1183 if (funcs->write != NULL)
1185 funcs->write (toval, fromval);
1192 error (_("Left operand of assignment is not an lvalue."));
1195 /* Assigning to the stack pointer, frame pointer, and other
1196 (architecture and calling convention specific) registers may
1197 cause the frame cache and regcache to be out of date. Assigning to memory
1198 also can. We just do this on all assignments to registers or
1199 memory, for simplicity's sake; I doubt the slowdown matters. */
1200 switch (VALUE_LVAL (toval))
1206 observer_notify_target_changed (¤t_target);
1208 /* Having destroyed the frame cache, restore the selected
1211 /* FIXME: cagney/2002-11-02: There has to be a better way of
1212 doing this. Instead of constantly saving/restoring the
1213 frame. Why not create a get_selected_frame() function that,
1214 having saved the selected frame's ID can automatically
1215 re-find the previously selected frame automatically. */
1218 struct frame_info *fi = frame_find_by_id (old_frame);
1229 /* If the field does not entirely fill a LONGEST, then zero the sign
1230 bits. If the field is signed, and is negative, then sign
1232 if ((value_bitsize (toval) > 0)
1233 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
1235 LONGEST fieldval = value_as_long (fromval);
1236 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
1238 fieldval &= valmask;
1239 if (!TYPE_UNSIGNED (type)
1240 && (fieldval & (valmask ^ (valmask >> 1))))
1241 fieldval |= ~valmask;
1243 fromval = value_from_longest (type, fieldval);
1246 /* The return value is a copy of TOVAL so it shares its location
1247 information, but its contents are updated from FROMVAL. This
1248 implies the returned value is not lazy, even if TOVAL was. */
1249 val = value_copy (toval);
1250 set_value_lazy (val, 0);
1251 memcpy (value_contents_raw (val), value_contents (fromval),
1252 TYPE_LENGTH (type));
1254 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1255 in the case of pointer types. For object types, the enclosing type
1256 and embedded offset must *not* be copied: the target object refered
1257 to by TOVAL retains its original dynamic type after assignment. */
1258 if (TYPE_CODE (type) == TYPE_CODE_PTR)
1260 set_value_enclosing_type (val, value_enclosing_type (fromval));
1261 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
1267 /* Extend a value VAL to COUNT repetitions of its type. */
1270 value_repeat (struct value *arg1, int count)
1274 if (VALUE_LVAL (arg1) != lval_memory)
1275 error (_("Only values in memory can be extended with '@'."));
1277 error (_("Invalid number %d of repetitions."), count);
1279 val = allocate_repeat_value (value_enclosing_type (arg1), count);
1281 VALUE_LVAL (val) = lval_memory;
1282 set_value_address (val, value_address (arg1));
1284 read_value_memory (val, 0, value_stack (val), value_address (val),
1285 value_contents_all_raw (val),
1286 type_length_units (value_enclosing_type (val)));
1292 value_of_variable (struct symbol *var, const struct block *b)
1294 struct frame_info *frame = NULL;
1296 if (symbol_read_needs_frame (var))
1297 frame = get_selected_frame (_("No frame selected."));
1299 return read_var_value (var, b, frame);
1303 address_of_variable (struct symbol *var, const struct block *b)
1305 struct type *type = SYMBOL_TYPE (var);
1308 /* Evaluate it first; if the result is a memory address, we're fine.
1309 Lazy evaluation pays off here. */
1311 val = value_of_variable (var, b);
1312 type = value_type (val);
1314 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
1315 || TYPE_CODE (type) == TYPE_CODE_FUNC)
1317 CORE_ADDR addr = value_address (val);
1319 return value_from_pointer (lookup_pointer_type (type), addr);
1322 /* Not a memory address; check what the problem was. */
1323 switch (VALUE_LVAL (val))
1327 struct frame_info *frame;
1328 const char *regname;
1330 frame = frame_find_by_id (VALUE_FRAME_ID (val));
1333 regname = gdbarch_register_name (get_frame_arch (frame),
1334 VALUE_REGNUM (val));
1335 gdb_assert (regname && *regname);
1337 error (_("Address requested for identifier "
1338 "\"%s\" which is in register $%s"),
1339 SYMBOL_PRINT_NAME (var), regname);
1344 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1345 SYMBOL_PRINT_NAME (var));
1352 /* Return one if VAL does not live in target memory, but should in order
1353 to operate on it. Otherwise return zero. */
1356 value_must_coerce_to_target (struct value *val)
1358 struct type *valtype;
1360 /* The only lval kinds which do not live in target memory. */
1361 if (VALUE_LVAL (val) != not_lval
1362 && VALUE_LVAL (val) != lval_internalvar
1363 && VALUE_LVAL (val) != lval_xcallable)
1366 valtype = check_typedef (value_type (val));
1368 switch (TYPE_CODE (valtype))
1370 case TYPE_CODE_ARRAY:
1371 return TYPE_VECTOR (valtype) ? 0 : 1;
1372 case TYPE_CODE_STRING:
1379 /* Make sure that VAL lives in target memory if it's supposed to. For
1380 instance, strings are constructed as character arrays in GDB's
1381 storage, and this function copies them to the target. */
1384 value_coerce_to_target (struct value *val)
1389 if (!value_must_coerce_to_target (val))
1392 length = TYPE_LENGTH (check_typedef (value_type (val)));
1393 addr = allocate_space_in_inferior (length);
1394 write_memory (addr, value_contents (val), length);
1395 return value_at_lazy (value_type (val), addr);
1398 /* Given a value which is an array, return a value which is a pointer
1399 to its first element, regardless of whether or not the array has a
1400 nonzero lower bound.
1402 FIXME: A previous comment here indicated that this routine should
1403 be substracting the array's lower bound. It's not clear to me that
1404 this is correct. Given an array subscripting operation, it would
1405 certainly work to do the adjustment here, essentially computing:
1407 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1409 However I believe a more appropriate and logical place to account
1410 for the lower bound is to do so in value_subscript, essentially
1413 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1415 As further evidence consider what would happen with operations
1416 other than array subscripting, where the caller would get back a
1417 value that had an address somewhere before the actual first element
1418 of the array, and the information about the lower bound would be
1419 lost because of the coercion to pointer type. */
1422 value_coerce_array (struct value *arg1)
1424 struct type *type = check_typedef (value_type (arg1));
1426 /* If the user tries to do something requiring a pointer with an
1427 array that has not yet been pushed to the target, then this would
1428 be a good time to do so. */
1429 arg1 = value_coerce_to_target (arg1);
1431 if (VALUE_LVAL (arg1) != lval_memory)
1432 error (_("Attempt to take address of value not located in memory."));
1434 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
1435 value_address (arg1));
1438 /* Given a value which is a function, return a value which is a pointer
1442 value_coerce_function (struct value *arg1)
1444 struct value *retval;
1446 if (VALUE_LVAL (arg1) != lval_memory)
1447 error (_("Attempt to take address of value not located in memory."));
1449 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1450 value_address (arg1));
1454 /* Return a pointer value for the object for which ARG1 is the
1458 value_addr (struct value *arg1)
1461 struct type *type = check_typedef (value_type (arg1));
1463 if (TYPE_CODE (type) == TYPE_CODE_REF)
1465 /* Copy the value, but change the type from (T&) to (T*). We
1466 keep the same location information, which is efficient, and
1467 allows &(&X) to get the location containing the reference. */
1468 arg2 = value_copy (arg1);
1469 deprecated_set_value_type (arg2,
1470 lookup_pointer_type (TYPE_TARGET_TYPE (type)));
1473 if (TYPE_CODE (type) == TYPE_CODE_FUNC)
1474 return value_coerce_function (arg1);
1476 /* If this is an array that has not yet been pushed to the target,
1477 then this would be a good time to force it to memory. */
1478 arg1 = value_coerce_to_target (arg1);
1480 if (VALUE_LVAL (arg1) != lval_memory)
1481 error (_("Attempt to take address of value not located in memory."));
1483 /* Get target memory address. */
1484 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
1485 (value_address (arg1)
1486 + value_embedded_offset (arg1)));
1488 /* This may be a pointer to a base subobject; so remember the
1489 full derived object's type ... */
1490 set_value_enclosing_type (arg2,
1491 lookup_pointer_type (value_enclosing_type (arg1)));
1492 /* ... and also the relative position of the subobject in the full
1494 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
1498 /* Return a reference value for the object for which ARG1 is the
1502 value_ref (struct value *arg1)
1505 struct type *type = check_typedef (value_type (arg1));
1507 if (TYPE_CODE (type) == TYPE_CODE_REF)
1510 arg2 = value_addr (arg1);
1511 deprecated_set_value_type (arg2, lookup_reference_type (type));
1515 /* Given a value of a pointer type, apply the C unary * operator to
1519 value_ind (struct value *arg1)
1521 struct type *base_type;
1524 arg1 = coerce_array (arg1);
1526 base_type = check_typedef (value_type (arg1));
1528 if (VALUE_LVAL (arg1) == lval_computed)
1530 const struct lval_funcs *funcs = value_computed_funcs (arg1);
1532 if (funcs->indirect)
1534 struct value *result = funcs->indirect (arg1);
1541 if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
1543 struct type *enc_type;
1545 /* We may be pointing to something embedded in a larger object.
1546 Get the real type of the enclosing object. */
1547 enc_type = check_typedef (value_enclosing_type (arg1));
1548 enc_type = TYPE_TARGET_TYPE (enc_type);
1550 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC
1551 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD)
1552 /* For functions, go through find_function_addr, which knows
1553 how to handle function descriptors. */
1554 arg2 = value_at_lazy (enc_type,
1555 find_function_addr (arg1, NULL));
1557 /* Retrieve the enclosing object pointed to. */
1558 arg2 = value_at_lazy (enc_type,
1559 (value_as_address (arg1)
1560 - value_pointed_to_offset (arg1)));
1562 enc_type = value_type (arg2);
1563 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1);
1566 error (_("Attempt to take contents of a non-pointer value."));
1567 return 0; /* For lint -- never reached. */
1570 /* Create a value for an array by allocating space in GDB, copying the
1571 data into that space, and then setting up an array value.
1573 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1574 is populated from the values passed in ELEMVEC.
1576 The element type of the array is inherited from the type of the
1577 first element, and all elements must have the same size (though we
1578 don't currently enforce any restriction on their types). */
1581 value_array (int lowbound, int highbound, struct value **elemvec)
1585 unsigned int typelength;
1587 struct type *arraytype;
1589 /* Validate that the bounds are reasonable and that each of the
1590 elements have the same size. */
1592 nelem = highbound - lowbound + 1;
1595 error (_("bad array bounds (%d, %d)"), lowbound, highbound);
1597 typelength = type_length_units (value_enclosing_type (elemvec[0]));
1598 for (idx = 1; idx < nelem; idx++)
1600 if (type_length_units (value_enclosing_type (elemvec[idx]))
1603 error (_("array elements must all be the same size"));
1607 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
1608 lowbound, highbound);
1610 if (!current_language->c_style_arrays)
1612 val = allocate_value (arraytype);
1613 for (idx = 0; idx < nelem; idx++)
1614 value_contents_copy (val, idx * typelength, elemvec[idx], 0,
1619 /* Allocate space to store the array, and then initialize it by
1620 copying in each element. */
1622 val = allocate_value (arraytype);
1623 for (idx = 0; idx < nelem; idx++)
1624 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
1629 value_cstring (char *ptr, ssize_t len, struct type *char_type)
1632 int lowbound = current_language->string_lower_bound;
1633 ssize_t highbound = len / TYPE_LENGTH (char_type);
1634 struct type *stringtype
1635 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
1637 val = allocate_value (stringtype);
1638 memcpy (value_contents_raw (val), ptr, len);
1642 /* Create a value for a string constant by allocating space in the
1643 inferior, copying the data into that space, and returning the
1644 address with type TYPE_CODE_STRING. PTR points to the string
1645 constant data; LEN is number of characters.
1647 Note that string types are like array of char types with a lower
1648 bound of zero and an upper bound of LEN - 1. Also note that the
1649 string may contain embedded null bytes. */
1652 value_string (char *ptr, ssize_t len, struct type *char_type)
1655 int lowbound = current_language->string_lower_bound;
1656 ssize_t highbound = len / TYPE_LENGTH (char_type);
1657 struct type *stringtype
1658 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
1660 val = allocate_value (stringtype);
1661 memcpy (value_contents_raw (val), ptr, len);
1666 /* See if we can pass arguments in T2 to a function which takes
1667 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1668 a NULL-terminated vector. If some arguments need coercion of some
1669 sort, then the coerced values are written into T2. Return value is
1670 0 if the arguments could be matched, or the position at which they
1673 STATICP is nonzero if the T1 argument list came from a static
1674 member function. T2 will still include the ``this'' pointer, but
1677 For non-static member functions, we ignore the first argument,
1678 which is the type of the instance variable. This is because we
1679 want to handle calls with objects from derived classes. This is
1680 not entirely correct: we should actually check to make sure that a
1681 requested operation is type secure, shouldn't we? FIXME. */
1684 typecmp (int staticp, int varargs, int nargs,
1685 struct field t1[], struct value *t2[])
1690 internal_error (__FILE__, __LINE__,
1691 _("typecmp: no argument list"));
1693 /* Skip ``this'' argument if applicable. T2 will always include
1699 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID;
1702 struct type *tt1, *tt2;
1707 tt1 = check_typedef (t1[i].type);
1708 tt2 = check_typedef (value_type (t2[i]));
1710 if (TYPE_CODE (tt1) == TYPE_CODE_REF
1711 /* We should be doing hairy argument matching, as below. */
1712 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1)))
1713 == TYPE_CODE (tt2)))
1715 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
1716 t2[i] = value_coerce_array (t2[i]);
1718 t2[i] = value_ref (t2[i]);
1722 /* djb - 20000715 - Until the new type structure is in the
1723 place, and we can attempt things like implicit conversions,
1724 we need to do this so you can take something like a map<const
1725 char *>, and properly access map["hello"], because the
1726 argument to [] will be a reference to a pointer to a char,
1727 and the argument will be a pointer to a char. */
1728 while (TYPE_CODE(tt1) == TYPE_CODE_REF
1729 || TYPE_CODE (tt1) == TYPE_CODE_PTR)
1731 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) );
1733 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY
1734 || TYPE_CODE(tt2) == TYPE_CODE_PTR
1735 || TYPE_CODE(tt2) == TYPE_CODE_REF)
1737 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
1739 if (TYPE_CODE (tt1) == TYPE_CODE (tt2))
1741 /* Array to pointer is a `trivial conversion' according to the
1744 /* We should be doing much hairier argument matching (see
1745 section 13.2 of the ARM), but as a quick kludge, just check
1746 for the same type code. */
1747 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i])))
1750 if (varargs || t2[i] == NULL)
1755 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1756 and *LAST_BOFFSET, and possibly throws an exception if the field
1757 search has yielded ambiguous results. */
1760 update_search_result (struct value **result_ptr, struct value *v,
1761 int *last_boffset, int boffset,
1762 const char *name, struct type *type)
1766 if (*result_ptr != NULL
1767 /* The result is not ambiguous if all the classes that are
1768 found occupy the same space. */
1769 && *last_boffset != boffset)
1770 error (_("base class '%s' is ambiguous in type '%s'"),
1771 name, TYPE_SAFE_NAME (type));
1773 *last_boffset = boffset;
1777 /* A helper for search_struct_field. This does all the work; most
1778 arguments are as passed to search_struct_field. The result is
1779 stored in *RESULT_PTR, which must be initialized to NULL.
1780 OUTERMOST_TYPE is the type of the initial type passed to
1781 search_struct_field; this is used for error reporting when the
1782 lookup is ambiguous. */
1785 do_search_struct_field (const char *name, struct value *arg1, int offset,
1786 struct type *type, int looking_for_baseclass,
1787 struct value **result_ptr,
1789 struct type *outermost_type)
1794 type = check_typedef (type);
1795 nbases = TYPE_N_BASECLASSES (type);
1797 if (!looking_for_baseclass)
1798 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
1800 const char *t_field_name = TYPE_FIELD_NAME (type, i);
1802 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1806 if (field_is_static (&TYPE_FIELD (type, i)))
1807 v = value_static_field (type, i);
1809 v = value_primitive_field (arg1, offset, i, type);
1815 && t_field_name[0] == '\0')
1817 struct type *field_type = TYPE_FIELD_TYPE (type, i);
1819 if (TYPE_CODE (field_type) == TYPE_CODE_UNION
1820 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
1822 /* Look for a match through the fields of an anonymous
1823 union, or anonymous struct. C++ provides anonymous
1826 In the GNU Chill (now deleted from GDB)
1827 implementation of variant record types, each
1828 <alternative field> has an (anonymous) union type,
1829 each member of the union represents a <variant
1830 alternative>. Each <variant alternative> is
1831 represented as a struct, with a member for each
1834 struct value *v = NULL;
1835 int new_offset = offset;
1837 /* This is pretty gross. In G++, the offset in an
1838 anonymous union is relative to the beginning of the
1839 enclosing struct. In the GNU Chill (now deleted
1840 from GDB) implementation of variant records, the
1841 bitpos is zero in an anonymous union field, so we
1842 have to add the offset of the union here. */
1843 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
1844 || (TYPE_NFIELDS (field_type) > 0
1845 && TYPE_FIELD_BITPOS (field_type, 0) == 0))
1846 new_offset += TYPE_FIELD_BITPOS (type, i) / 8;
1848 do_search_struct_field (name, arg1, new_offset,
1850 looking_for_baseclass, &v,
1862 for (i = 0; i < nbases; i++)
1864 struct value *v = NULL;
1865 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
1866 /* If we are looking for baseclasses, this is what we get when
1867 we hit them. But it could happen that the base part's member
1868 name is not yet filled in. */
1869 int found_baseclass = (looking_for_baseclass
1870 && TYPE_BASECLASS_NAME (type, i) != NULL
1871 && (strcmp_iw (name,
1872 TYPE_BASECLASS_NAME (type,
1874 int boffset = value_embedded_offset (arg1) + offset;
1876 if (BASETYPE_VIA_VIRTUAL (type, i))
1880 boffset = baseclass_offset (type, i,
1881 value_contents_for_printing (arg1),
1882 value_embedded_offset (arg1) + offset,
1883 value_address (arg1),
1886 /* The virtual base class pointer might have been clobbered
1887 by the user program. Make sure that it still points to a
1888 valid memory location. */
1890 boffset += value_embedded_offset (arg1) + offset;
1892 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
1894 CORE_ADDR base_addr;
1896 base_addr = value_address (arg1) + boffset;
1897 v2 = value_at_lazy (basetype, base_addr);
1898 if (target_read_memory (base_addr,
1899 value_contents_raw (v2),
1900 TYPE_LENGTH (value_type (v2))) != 0)
1901 error (_("virtual baseclass botch"));
1905 v2 = value_copy (arg1);
1906 deprecated_set_value_type (v2, basetype);
1907 set_value_embedded_offset (v2, boffset);
1910 if (found_baseclass)
1914 do_search_struct_field (name, v2, 0,
1915 TYPE_BASECLASS (type, i),
1916 looking_for_baseclass,
1917 result_ptr, last_boffset,
1921 else if (found_baseclass)
1922 v = value_primitive_field (arg1, offset, i, type);
1925 do_search_struct_field (name, arg1,
1926 offset + TYPE_BASECLASS_BITPOS (type,
1928 basetype, looking_for_baseclass,
1929 result_ptr, last_boffset,
1933 update_search_result (result_ptr, v, last_boffset,
1934 boffset, name, outermost_type);
1938 /* Helper function used by value_struct_elt to recurse through
1939 baseclasses. Look for a field NAME in ARG1. Search in it assuming
1940 it has (class) type TYPE. If found, return value, else return NULL.
1942 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1943 fields, look for a baseclass named NAME. */
1945 static struct value *
1946 search_struct_field (const char *name, struct value *arg1,
1947 struct type *type, int looking_for_baseclass)
1949 struct value *result = NULL;
1952 do_search_struct_field (name, arg1, 0, type, looking_for_baseclass,
1953 &result, &boffset, type);
1957 /* Helper function used by value_struct_elt to recurse through
1958 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1959 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1962 If found, return value, else if name matched and args not return
1963 (value) -1, else return NULL. */
1965 static struct value *
1966 search_struct_method (const char *name, struct value **arg1p,
1967 struct value **args, int offset,
1968 int *static_memfuncp, struct type *type)
1972 int name_matched = 0;
1973 char dem_opname[64];
1975 type = check_typedef (type);
1976 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
1978 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
1980 /* FIXME! May need to check for ARM demangling here. */
1981 if (startswith (t_field_name, "__") ||
1982 startswith (t_field_name, "op") ||
1983 startswith (t_field_name, "type"))
1985 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI))
1986 t_field_name = dem_opname;
1987 else if (cplus_demangle_opname (t_field_name, dem_opname, 0))
1988 t_field_name = dem_opname;
1990 if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
1992 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
1993 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
1996 check_stub_method_group (type, i);
1997 if (j > 0 && args == 0)
1998 error (_("cannot resolve overloaded method "
1999 "`%s': no arguments supplied"), name);
2000 else if (j == 0 && args == 0)
2002 v = value_fn_field (arg1p, f, j, type, offset);
2009 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
2010 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)),
2011 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)),
2012 TYPE_FN_FIELD_ARGS (f, j), args))
2014 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
2015 return value_virtual_fn_field (arg1p, f, j,
2017 if (TYPE_FN_FIELD_STATIC_P (f, j)
2019 *static_memfuncp = 1;
2020 v = value_fn_field (arg1p, f, j, type, offset);
2029 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2034 if (BASETYPE_VIA_VIRTUAL (type, i))
2036 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
2037 struct value *base_val;
2038 const gdb_byte *base_valaddr;
2040 /* The virtual base class pointer might have been
2041 clobbered by the user program. Make sure that it
2042 still points to a valid memory location. */
2044 if (offset < 0 || offset >= TYPE_LENGTH (type))
2047 struct cleanup *back_to;
2050 tmp = xmalloc (TYPE_LENGTH (baseclass));
2051 back_to = make_cleanup (xfree, tmp);
2052 address = value_address (*arg1p);
2054 if (target_read_memory (address + offset,
2055 tmp, TYPE_LENGTH (baseclass)) != 0)
2056 error (_("virtual baseclass botch"));
2058 base_val = value_from_contents_and_address (baseclass,
2061 base_valaddr = value_contents_for_printing (base_val);
2063 do_cleanups (back_to);
2068 base_valaddr = value_contents_for_printing (*arg1p);
2069 this_offset = offset;
2072 base_offset = baseclass_offset (type, i, base_valaddr,
2073 this_offset, value_address (base_val),
2078 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2080 v = search_struct_method (name, arg1p, args, base_offset + offset,
2081 static_memfuncp, TYPE_BASECLASS (type, i));
2082 if (v == (struct value *) - 1)
2088 /* FIXME-bothner: Why is this commented out? Why is it here? */
2089 /* *arg1p = arg1_tmp; */
2094 return (struct value *) - 1;
2099 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2100 extract the component named NAME from the ultimate target
2101 structure/union and return it as a value with its appropriate type.
2102 ERR is used in the error message if *ARGP's type is wrong.
2104 C++: ARGS is a list of argument types to aid in the selection of
2105 an appropriate method. Also, handle derived types.
2107 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2108 where the truthvalue of whether the function that was resolved was
2109 a static member function or not is stored.
2111 ERR is an error message to be printed in case the field is not
2115 value_struct_elt (struct value **argp, struct value **args,
2116 const char *name, int *static_memfuncp, const char *err)
2121 *argp = coerce_array (*argp);
2123 t = check_typedef (value_type (*argp));
2125 /* Follow pointers until we get to a non-pointer. */
2127 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2129 *argp = value_ind (*argp);
2130 /* Don't coerce fn pointer to fn and then back again! */
2131 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2132 *argp = coerce_array (*argp);
2133 t = check_typedef (value_type (*argp));
2136 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2137 && TYPE_CODE (t) != TYPE_CODE_UNION)
2138 error (_("Attempt to extract a component of a value that is not a %s."),
2141 /* Assume it's not, unless we see that it is. */
2142 if (static_memfuncp)
2143 *static_memfuncp = 0;
2147 /* if there are no arguments ...do this... */
2149 /* Try as a field first, because if we succeed, there is less
2151 v = search_struct_field (name, *argp, t, 0);
2155 /* C++: If it was not found as a data field, then try to
2156 return it as a pointer to a method. */
2157 v = search_struct_method (name, argp, args, 0,
2158 static_memfuncp, t);
2160 if (v == (struct value *) - 1)
2161 error (_("Cannot take address of method %s."), name);
2164 if (TYPE_NFN_FIELDS (t))
2165 error (_("There is no member or method named %s."), name);
2167 error (_("There is no member named %s."), name);
2172 v = search_struct_method (name, argp, args, 0,
2173 static_memfuncp, t);
2175 if (v == (struct value *) - 1)
2177 error (_("One of the arguments you tried to pass to %s could not "
2178 "be converted to what the function wants."), name);
2182 /* See if user tried to invoke data as function. If so, hand it
2183 back. If it's not callable (i.e., a pointer to function),
2184 gdb should give an error. */
2185 v = search_struct_field (name, *argp, t, 0);
2186 /* If we found an ordinary field, then it is not a method call.
2187 So, treat it as if it were a static member function. */
2188 if (v && static_memfuncp)
2189 *static_memfuncp = 1;
2193 throw_error (NOT_FOUND_ERROR,
2194 _("Structure has no component named %s."), name);
2198 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2199 to a structure or union, extract and return its component (field) of
2200 type FTYPE at the specified BITPOS.
2201 Throw an exception on error. */
2204 value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
2212 *argp = coerce_array (*argp);
2214 t = check_typedef (value_type (*argp));
2216 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2218 *argp = value_ind (*argp);
2219 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2220 *argp = coerce_array (*argp);
2221 t = check_typedef (value_type (*argp));
2224 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2225 && TYPE_CODE (t) != TYPE_CODE_UNION)
2226 error (_("Attempt to extract a component of a value that is not a %s."),
2229 for (i = TYPE_N_BASECLASSES (t); i < TYPE_NFIELDS (t); i++)
2231 if (!field_is_static (&TYPE_FIELD (t, i))
2232 && bitpos == TYPE_FIELD_BITPOS (t, i)
2233 && types_equal (ftype, TYPE_FIELD_TYPE (t, i)))
2234 return value_primitive_field (*argp, 0, i, t);
2237 error (_("No field with matching bitpos and type."));
2243 /* Search through the methods of an object (and its bases) to find a
2244 specified method. Return the pointer to the fn_field list FN_LIST of
2245 overloaded instances defined in the source language. If available
2246 and matching, a vector of matching xmethods defined in extension
2247 languages are also returned in XM_WORKER_VEC
2249 Helper function for value_find_oload_list.
2250 ARGP is a pointer to a pointer to a value (the object).
2251 METHOD is a string containing the method name.
2252 OFFSET is the offset within the value.
2253 TYPE is the assumed type of the object.
2254 FN_LIST is the pointer to matching overloaded instances defined in
2255 source language. Since this is a recursive function, *FN_LIST
2256 should be set to NULL when calling this function.
2257 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2258 0 when calling this function.
2259 XM_WORKER_VEC is the vector of matching xmethod workers. *XM_WORKER_VEC
2260 should also be set to NULL when calling this function.
2261 BASETYPE is set to the actual type of the subobject where the
2263 BOFFSET is the offset of the base subobject where the method is found. */
2266 find_method_list (struct value **argp, const char *method,
2267 int offset, struct type *type,
2268 struct fn_field **fn_list, int *num_fns,
2269 VEC (xmethod_worker_ptr) **xm_worker_vec,
2270 struct type **basetype, int *boffset)
2273 struct fn_field *f = NULL;
2274 VEC (xmethod_worker_ptr) *worker_vec = NULL, *new_vec = NULL;
2276 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2277 type = check_typedef (type);
2279 /* First check in object itself.
2280 This function is called recursively to search through base classes.
2281 If there is a source method match found at some stage, then we need not
2282 look for source methods in consequent recursive calls. */
2283 if ((*fn_list) == NULL)
2285 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
2287 /* pai: FIXME What about operators and type conversions? */
2288 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
2290 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
2292 int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
2293 f = TYPE_FN_FIELDLIST1 (type, i);
2300 /* Resolve any stub methods. */
2301 check_stub_method_group (type, i);
2308 /* Unlike source methods, xmethods can be accumulated over successive
2309 recursive calls. In other words, an xmethod named 'm' in a class
2310 will not hide an xmethod named 'm' in its base class(es). We want
2311 it to be this way because xmethods are after all convenience functions
2312 and hence there is no point restricting them with something like method
2313 hiding. Moreover, if hiding is done for xmethods as well, then we will
2314 have to provide a mechanism to un-hide (like the 'using' construct). */
2315 worker_vec = get_matching_xmethod_workers (type, method);
2316 new_vec = VEC_merge (xmethod_worker_ptr, *xm_worker_vec, worker_vec);
2318 VEC_free (xmethod_worker_ptr, *xm_worker_vec);
2319 VEC_free (xmethod_worker_ptr, worker_vec);
2320 *xm_worker_vec = new_vec;
2322 /* If source methods are not found in current class, look for them in the
2323 base classes. We also have to go through the base classes to gather
2324 extension methods. */
2325 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
2329 if (BASETYPE_VIA_VIRTUAL (type, i))
2331 base_offset = baseclass_offset (type, i,
2332 value_contents_for_printing (*argp),
2333 value_offset (*argp) + offset,
2334 value_address (*argp), *argp);
2336 else /* Non-virtual base, simply use bit position from debug
2339 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
2342 find_method_list (argp, method, base_offset + offset,
2343 TYPE_BASECLASS (type, i), fn_list, num_fns,
2344 xm_worker_vec, basetype, boffset);
2348 /* Return the list of overloaded methods of a specified name. The methods
2349 could be those GDB finds in the binary, or xmethod. Methods found in
2350 the binary are returned in FN_LIST, and xmethods are returned in
2353 ARGP is a pointer to a pointer to a value (the object).
2354 METHOD is the method name.
2355 OFFSET is the offset within the value contents.
2356 FN_LIST is the pointer to matching overloaded instances defined in
2358 NUM_FNS is the number of overloaded instances.
2359 XM_WORKER_VEC is the vector of matching xmethod workers defined in
2360 extension languages.
2361 BASETYPE is set to the type of the base subobject that defines the
2363 BOFFSET is the offset of the base subobject which defines the method. */
2366 value_find_oload_method_list (struct value **argp, const char *method,
2367 int offset, struct fn_field **fn_list,
2369 VEC (xmethod_worker_ptr) **xm_worker_vec,
2370 struct type **basetype, int *boffset)
2374 t = check_typedef (value_type (*argp));
2376 /* Code snarfed from value_struct_elt. */
2377 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
2379 *argp = value_ind (*argp);
2380 /* Don't coerce fn pointer to fn and then back again! */
2381 if (TYPE_CODE (check_typedef (value_type (*argp))) != TYPE_CODE_FUNC)
2382 *argp = coerce_array (*argp);
2383 t = check_typedef (value_type (*argp));
2386 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
2387 && TYPE_CODE (t) != TYPE_CODE_UNION)
2388 error (_("Attempt to extract a component of a "
2389 "value that is not a struct or union"));
2391 gdb_assert (fn_list != NULL && xm_worker_vec != NULL);
2393 /* Clear the lists. */
2396 *xm_worker_vec = NULL;
2398 find_method_list (argp, method, 0, t, fn_list, num_fns, xm_worker_vec,
2402 /* Given an array of arguments (ARGS) (which includes an
2403 entry for "this" in the case of C++ methods), the number of
2404 arguments NARGS, the NAME of a function, and whether it's a method or
2405 not (METHOD), find the best function that matches on the argument types
2406 according to the overload resolution rules.
2408 METHOD can be one of three values:
2409 NON_METHOD for non-member functions.
2410 METHOD: for member functions.
2411 BOTH: used for overload resolution of operators where the
2412 candidates are expected to be either member or non member
2413 functions. In this case the first argument ARGTYPES
2414 (representing 'this') is expected to be a reference to the
2415 target object, and will be dereferenced when attempting the
2418 In the case of class methods, the parameter OBJ is an object value
2419 in which to search for overloaded methods.
2421 In the case of non-method functions, the parameter FSYM is a symbol
2422 corresponding to one of the overloaded functions.
2424 Return value is an integer: 0 -> good match, 10 -> debugger applied
2425 non-standard coercions, 100 -> incompatible.
2427 If a method is being searched for, VALP will hold the value.
2428 If a non-method is being searched for, SYMP will hold the symbol
2431 If a method is being searched for, and it is a static method,
2432 then STATICP will point to a non-zero value.
2434 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2435 ADL overload candidates when performing overload resolution for a fully
2438 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2439 read while picking the best overload match (it may be all zeroes and thus
2440 not have a vtable pointer), in which case skip virtual function lookup.
2441 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2444 Note: This function does *not* check the value of
2445 overload_resolution. Caller must check it to see whether overload
2446 resolution is permitted. */
2449 find_overload_match (struct value **args, int nargs,
2450 const char *name, enum oload_search_type method,
2451 struct value **objp, struct symbol *fsym,
2452 struct value **valp, struct symbol **symp,
2453 int *staticp, const int no_adl,
2454 const enum noside noside)
2456 struct value *obj = (objp ? *objp : NULL);
2457 struct type *obj_type = obj ? value_type (obj) : NULL;
2458 /* Index of best overloaded function. */
2459 int func_oload_champ = -1;
2460 int method_oload_champ = -1;
2461 int src_method_oload_champ = -1;
2462 int ext_method_oload_champ = -1;
2463 int src_and_ext_equal = 0;
2465 /* The measure for the current best match. */
2466 struct badness_vector *method_badness = NULL;
2467 struct badness_vector *func_badness = NULL;
2468 struct badness_vector *ext_method_badness = NULL;
2469 struct badness_vector *src_method_badness = NULL;
2471 struct value *temp = obj;
2472 /* For methods, the list of overloaded methods. */
2473 struct fn_field *fns_ptr = NULL;
2474 /* For non-methods, the list of overloaded function symbols. */
2475 struct symbol **oload_syms = NULL;
2476 /* For xmethods, the VEC of xmethod workers. */
2477 VEC (xmethod_worker_ptr) *xm_worker_vec = NULL;
2478 /* Number of overloaded instances being considered. */
2480 struct type *basetype = NULL;
2483 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL);
2485 const char *obj_type_name = NULL;
2486 const char *func_name = NULL;
2487 enum oload_classification match_quality;
2488 enum oload_classification method_match_quality = INCOMPATIBLE;
2489 enum oload_classification src_method_match_quality = INCOMPATIBLE;
2490 enum oload_classification ext_method_match_quality = INCOMPATIBLE;
2491 enum oload_classification func_match_quality = INCOMPATIBLE;
2493 /* Get the list of overloaded methods or functions. */
2494 if (method == METHOD || method == BOTH)
2498 /* OBJ may be a pointer value rather than the object itself. */
2499 obj = coerce_ref (obj);
2500 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR)
2501 obj = coerce_ref (value_ind (obj));
2502 obj_type_name = TYPE_NAME (value_type (obj));
2504 /* First check whether this is a data member, e.g. a pointer to
2506 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT)
2508 *valp = search_struct_field (name, obj,
2509 check_typedef (value_type (obj)), 0);
2513 do_cleanups (all_cleanups);
2518 /* Retrieve the list of methods with the name NAME. */
2519 value_find_oload_method_list (&temp, name, 0, &fns_ptr, &num_fns,
2520 &xm_worker_vec, &basetype, &boffset);
2521 /* If this is a method only search, and no methods were found
2522 the search has faild. */
2523 if (method == METHOD && (!fns_ptr || !num_fns) && !xm_worker_vec)
2524 error (_("Couldn't find method %s%s%s"),
2526 (obj_type_name && *obj_type_name) ? "::" : "",
2528 /* If we are dealing with stub method types, they should have
2529 been resolved by find_method_list via
2530 value_find_oload_method_list above. */
2533 gdb_assert (TYPE_SELF_TYPE (fns_ptr[0].type) != NULL);
2535 src_method_oload_champ = find_oload_champ (args, nargs,
2536 num_fns, fns_ptr, NULL,
2537 NULL, &src_method_badness);
2539 src_method_match_quality = classify_oload_match
2540 (src_method_badness, nargs,
2541 oload_method_static_p (fns_ptr, src_method_oload_champ));
2543 make_cleanup (xfree, src_method_badness);
2546 if (VEC_length (xmethod_worker_ptr, xm_worker_vec) > 0)
2548 ext_method_oload_champ = find_oload_champ (args, nargs,
2549 0, NULL, xm_worker_vec,
2550 NULL, &ext_method_badness);
2551 ext_method_match_quality = classify_oload_match (ext_method_badness,
2553 make_cleanup (xfree, ext_method_badness);
2554 make_cleanup (free_xmethod_worker_vec, xm_worker_vec);
2557 if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
2559 switch (compare_badness (ext_method_badness, src_method_badness))
2561 case 0: /* Src method and xmethod are equally good. */
2562 src_and_ext_equal = 1;
2563 /* If src method and xmethod are equally good, then
2564 xmethod should be the winner. Hence, fall through to the
2565 case where a xmethod is better than the source
2566 method, except when the xmethod match quality is
2569 case 1: /* Src method and ext method are incompatible. */
2570 /* If ext method match is not standard, then let source method
2571 win. Otherwise, fallthrough to let xmethod win. */
2572 if (ext_method_match_quality != STANDARD)
2574 method_oload_champ = src_method_oload_champ;
2575 method_badness = src_method_badness;
2576 ext_method_oload_champ = -1;
2577 method_match_quality = src_method_match_quality;
2581 case 2: /* Ext method is champion. */
2582 method_oload_champ = ext_method_oload_champ;
2583 method_badness = ext_method_badness;
2584 src_method_oload_champ = -1;
2585 method_match_quality = ext_method_match_quality;
2587 case 3: /* Src method is champion. */
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;
2594 gdb_assert_not_reached ("Unexpected overload comparison "
2599 else if (src_method_oload_champ >= 0)
2601 method_oload_champ = src_method_oload_champ;
2602 method_badness = src_method_badness;
2603 method_match_quality = src_method_match_quality;
2605 else if (ext_method_oload_champ >= 0)
2607 method_oload_champ = ext_method_oload_champ;
2608 method_badness = ext_method_badness;
2609 method_match_quality = ext_method_match_quality;
2613 if (method == NON_METHOD || method == BOTH)
2615 const char *qualified_name = NULL;
2617 /* If the overload match is being search for both as a method
2618 and non member function, the first argument must now be
2621 args[0] = value_ind (args[0]);
2625 qualified_name = SYMBOL_NATURAL_NAME (fsym);
2627 /* If we have a function with a C++ name, try to extract just
2628 the function part. Do not try this for non-functions (e.g.
2629 function pointers). */
2631 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym)))
2636 temp = cp_func_name (qualified_name);
2638 /* If cp_func_name did not remove anything, the name of the
2639 symbol did not include scope or argument types - it was
2640 probably a C-style function. */
2643 make_cleanup (xfree, temp);
2644 if (strcmp (temp, qualified_name) == 0)
2654 qualified_name = name;
2657 /* If there was no C++ name, this must be a C-style function or
2658 not a function at all. Just return the same symbol. Do the
2659 same if cp_func_name fails for some reason. */
2660 if (func_name == NULL)
2663 do_cleanups (all_cleanups);
2667 func_oload_champ = find_oload_champ_namespace (args, nargs,
2674 if (func_oload_champ >= 0)
2675 func_match_quality = classify_oload_match (func_badness, nargs, 0);
2677 make_cleanup (xfree, oload_syms);
2678 make_cleanup (xfree, func_badness);
2681 /* Did we find a match ? */
2682 if (method_oload_champ == -1 && func_oload_champ == -1)
2683 throw_error (NOT_FOUND_ERROR,
2684 _("No symbol \"%s\" in current context."),
2687 /* If we have found both a method match and a function
2688 match, find out which one is better, and calculate match
2690 if (method_oload_champ >= 0 && func_oload_champ >= 0)
2692 switch (compare_badness (func_badness, method_badness))
2694 case 0: /* Top two contenders are equally good. */
2695 /* FIXME: GDB does not support the general ambiguous case.
2696 All candidates should be collected and presented the
2698 error (_("Ambiguous overload resolution"));
2700 case 1: /* Incomparable top contenders. */
2701 /* This is an error incompatible candidates
2702 should not have been proposed. */
2703 error (_("Internal error: incompatible "
2704 "overload candidates proposed"));
2706 case 2: /* Function champion. */
2707 method_oload_champ = -1;
2708 match_quality = func_match_quality;
2710 case 3: /* Method champion. */
2711 func_oload_champ = -1;
2712 match_quality = method_match_quality;
2715 error (_("Internal error: unexpected overload comparison result"));
2721 /* We have either a method match or a function match. */
2722 if (method_oload_champ >= 0)
2723 match_quality = method_match_quality;
2725 match_quality = func_match_quality;
2728 if (match_quality == INCOMPATIBLE)
2730 if (method == METHOD)
2731 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2733 (obj_type_name && *obj_type_name) ? "::" : "",
2736 error (_("Cannot resolve function %s to any overloaded instance"),
2739 else if (match_quality == NON_STANDARD)
2741 if (method == METHOD)
2742 warning (_("Using non-standard conversion to match "
2743 "method %s%s%s to supplied arguments"),
2745 (obj_type_name && *obj_type_name) ? "::" : "",
2748 warning (_("Using non-standard conversion to match "
2749 "function %s to supplied arguments"),
2753 if (staticp != NULL)
2754 *staticp = oload_method_static_p (fns_ptr, method_oload_champ);
2756 if (method_oload_champ >= 0)
2758 if (src_method_oload_champ >= 0)
2760 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)
2761 && noside != EVAL_AVOID_SIDE_EFFECTS)
2763 *valp = value_virtual_fn_field (&temp, fns_ptr,
2764 method_oload_champ, basetype,
2768 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ,
2773 *valp = value_of_xmethod (clone_xmethod_worker
2774 (VEC_index (xmethod_worker_ptr, xm_worker_vec,
2775 ext_method_oload_champ)));
2779 *symp = oload_syms[func_oload_champ];
2783 struct type *temp_type = check_typedef (value_type (temp));
2784 struct type *objtype = check_typedef (obj_type);
2786 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR
2787 && (TYPE_CODE (objtype) == TYPE_CODE_PTR
2788 || TYPE_CODE (objtype) == TYPE_CODE_REF))
2790 temp = value_addr (temp);
2795 do_cleanups (all_cleanups);
2797 switch (match_quality)
2803 default: /* STANDARD */
2808 /* Find the best overload match, searching for FUNC_NAME in namespaces
2809 contained in QUALIFIED_NAME until it either finds a good match or
2810 runs out of namespaces. It stores the overloaded functions in
2811 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The
2812 calling function is responsible for freeing *OLOAD_SYMS and
2813 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not
2817 find_oload_champ_namespace (struct value **args, int nargs,
2818 const char *func_name,
2819 const char *qualified_name,
2820 struct symbol ***oload_syms,
2821 struct badness_vector **oload_champ_bv,
2826 find_oload_champ_namespace_loop (args, nargs,
2829 oload_syms, oload_champ_bv,
2836 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2837 how deep we've looked for namespaces, and the champ is stored in
2838 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2839 if it isn't. Other arguments are the same as in
2840 find_oload_champ_namespace
2842 It is the caller's responsibility to free *OLOAD_SYMS and
2846 find_oload_champ_namespace_loop (struct value **args, int nargs,
2847 const char *func_name,
2848 const char *qualified_name,
2850 struct symbol ***oload_syms,
2851 struct badness_vector **oload_champ_bv,
2855 int next_namespace_len = namespace_len;
2856 int searched_deeper = 0;
2858 struct cleanup *old_cleanups;
2859 int new_oload_champ;
2860 struct symbol **new_oload_syms;
2861 struct badness_vector *new_oload_champ_bv;
2862 char *new_namespace;
2864 if (next_namespace_len != 0)
2866 gdb_assert (qualified_name[next_namespace_len] == ':');
2867 next_namespace_len += 2;
2869 next_namespace_len +=
2870 cp_find_first_component (qualified_name + next_namespace_len);
2872 /* Initialize these to values that can safely be xfree'd. */
2874 *oload_champ_bv = NULL;
2876 /* First, see if we have a deeper namespace we can search in.
2877 If we get a good match there, use it. */
2879 if (qualified_name[next_namespace_len] == ':')
2881 searched_deeper = 1;
2883 if (find_oload_champ_namespace_loop (args, nargs,
2884 func_name, qualified_name,
2886 oload_syms, oload_champ_bv,
2887 oload_champ, no_adl))
2893 /* If we reach here, either we're in the deepest namespace or we
2894 didn't find a good match in a deeper namespace. But, in the
2895 latter case, we still have a bad match in a deeper namespace;
2896 note that we might not find any match at all in the current
2897 namespace. (There's always a match in the deepest namespace,
2898 because this overload mechanism only gets called if there's a
2899 function symbol to start off with.) */
2901 old_cleanups = make_cleanup (xfree, *oload_syms);
2902 make_cleanup (xfree, *oload_champ_bv);
2903 new_namespace = alloca (namespace_len + 1);
2904 strncpy (new_namespace, qualified_name, namespace_len);
2905 new_namespace[namespace_len] = '\0';
2906 new_oload_syms = make_symbol_overload_list (func_name,
2909 /* If we have reached the deepest level perform argument
2910 determined lookup. */
2911 if (!searched_deeper && !no_adl)
2914 struct type **arg_types;
2916 /* Prepare list of argument types for overload resolution. */
2917 arg_types = (struct type **)
2918 alloca (nargs * (sizeof (struct type *)));
2919 for (ix = 0; ix < nargs; ix++)
2920 arg_types[ix] = value_type (args[ix]);
2921 make_symbol_overload_list_adl (arg_types, nargs, func_name);
2924 while (new_oload_syms[num_fns])
2927 new_oload_champ = find_oload_champ (args, nargs, num_fns,
2928 NULL, NULL, new_oload_syms,
2929 &new_oload_champ_bv);
2931 /* Case 1: We found a good match. Free earlier matches (if any),
2932 and return it. Case 2: We didn't find a good match, but we're
2933 not the deepest function. Then go with the bad match that the
2934 deeper function found. Case 3: We found a bad match, and we're
2935 the deepest function. Then return what we found, even though
2936 it's a bad match. */
2938 if (new_oload_champ != -1
2939 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD)
2941 *oload_syms = new_oload_syms;
2942 *oload_champ = new_oload_champ;
2943 *oload_champ_bv = new_oload_champ_bv;
2944 do_cleanups (old_cleanups);
2947 else if (searched_deeper)
2949 xfree (new_oload_syms);
2950 xfree (new_oload_champ_bv);
2951 discard_cleanups (old_cleanups);
2956 *oload_syms = new_oload_syms;
2957 *oload_champ = new_oload_champ;
2958 *oload_champ_bv = new_oload_champ_bv;
2959 do_cleanups (old_cleanups);
2964 /* Look for a function to take NARGS args of ARGS. Find
2965 the best match from among the overloaded methods or functions
2966 given by FNS_PTR or OLOAD_SYMS or XM_WORKER_VEC, respectively.
2967 One, and only one of FNS_PTR, OLOAD_SYMS and XM_WORKER_VEC can be
2970 If XM_WORKER_VEC is NULL, then the length of the arrays FNS_PTR
2971 or OLOAD_SYMS (whichever is non-NULL) is specified in NUM_FNS.
2973 Return the index of the best match; store an indication of the
2974 quality of the match in OLOAD_CHAMP_BV.
2976 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */
2979 find_oload_champ (struct value **args, int nargs,
2980 int num_fns, struct fn_field *fns_ptr,
2981 VEC (xmethod_worker_ptr) *xm_worker_vec,
2982 struct symbol **oload_syms,
2983 struct badness_vector **oload_champ_bv)
2987 int xm_worker_vec_n = VEC_length (xmethod_worker_ptr, xm_worker_vec);
2988 /* A measure of how good an overloaded instance is. */
2989 struct badness_vector *bv;
2990 /* Index of best overloaded function. */
2991 int oload_champ = -1;
2992 /* Current ambiguity state for overload resolution. */
2993 int oload_ambiguous = 0;
2994 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2996 /* A champion can be found among methods alone, or among functions
2997 alone, or in xmethods alone, but not in more than one of these
2999 gdb_assert ((fns_ptr != NULL) + (oload_syms != NULL) + (xm_worker_vec != NULL)
3002 *oload_champ_bv = NULL;
3004 fn_count = (xm_worker_vec != NULL
3005 ? VEC_length (xmethod_worker_ptr, xm_worker_vec)
3007 /* Consider each candidate in turn. */
3008 for (ix = 0; ix < fn_count; ix++)
3011 int static_offset = 0;
3013 struct type **parm_types;
3014 struct xmethod_worker *worker = NULL;
3016 if (xm_worker_vec != NULL)
3018 worker = VEC_index (xmethod_worker_ptr, xm_worker_vec, ix);
3019 parm_types = get_xmethod_arg_types (worker, &nparms);
3023 if (fns_ptr != NULL)
3025 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix));
3026 static_offset = oload_method_static_p (fns_ptr, ix);
3029 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));
3031 parm_types = XNEWVEC (struct type *, nparms);
3032 for (jj = 0; jj < nparms; jj++)
3033 parm_types[jj] = (fns_ptr != NULL
3034 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type)
3035 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]),
3039 /* Compare parameter types to supplied argument types. Skip
3040 THIS for static methods. */
3041 bv = rank_function (parm_types, nparms,
3042 args + static_offset,
3043 nargs - static_offset);
3045 if (!*oload_champ_bv)
3047 *oload_champ_bv = bv;
3050 else /* See whether current candidate is better or worse than
3052 switch (compare_badness (bv, *oload_champ_bv))
3054 case 0: /* Top two contenders are equally good. */
3055 oload_ambiguous = 1;
3057 case 1: /* Incomparable top contenders. */
3058 oload_ambiguous = 2;
3060 case 2: /* New champion, record details. */
3061 *oload_champ_bv = bv;
3062 oload_ambiguous = 0;
3072 if (fns_ptr != NULL)
3073 fprintf_filtered (gdb_stderr,
3074 "Overloaded method instance %s, # of parms %d\n",
3075 fns_ptr[ix].physname, nparms);
3076 else if (xm_worker_vec != NULL)
3077 fprintf_filtered (gdb_stderr,
3078 "Xmethod worker, # of parms %d\n",
3081 fprintf_filtered (gdb_stderr,
3082 "Overloaded function instance "
3083 "%s # of parms %d\n",
3084 SYMBOL_DEMANGLED_NAME (oload_syms[ix]),
3086 for (jj = 0; jj < nargs - static_offset; jj++)
3087 fprintf_filtered (gdb_stderr,
3088 "...Badness @ %d : %d\n",
3089 jj, bv->rank[jj].rank);
3090 fprintf_filtered (gdb_stderr, "Overload resolution "
3091 "champion is %d, ambiguous? %d\n",
3092 oload_champ, oload_ambiguous);
3099 /* Return 1 if we're looking at a static method, 0 if we're looking at
3100 a non-static method or a function that isn't a method. */
3103 oload_method_static_p (struct fn_field *fns_ptr, int index)
3105 if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
3111 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3113 static enum oload_classification
3114 classify_oload_match (struct badness_vector *oload_champ_bv,
3119 enum oload_classification worst = STANDARD;
3121 for (ix = 1; ix <= nargs - static_offset; ix++)
3123 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3124 or worse return INCOMPATIBLE. */
3125 if (compare_ranks (oload_champ_bv->rank[ix],
3126 INCOMPATIBLE_TYPE_BADNESS) <= 0)
3127 return INCOMPATIBLE; /* Truly mismatched types. */
3128 /* Otherwise If this conversion is as bad as
3129 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3130 else if (compare_ranks (oload_champ_bv->rank[ix],
3131 NS_POINTER_CONVERSION_BADNESS) <= 0)
3132 worst = NON_STANDARD; /* Non-standard type conversions
3136 /* If no INCOMPATIBLE classification was found, return the worst one
3137 that was found (if any). */
3141 /* C++: return 1 is NAME is a legitimate name for the destructor of
3142 type TYPE. If TYPE does not have a destructor, or if NAME is
3143 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3144 have CHECK_TYPEDEF applied, this function will apply it itself. */
3147 destructor_name_p (const char *name, struct type *type)
3151 const char *dname = type_name_no_tag_or_error (type);
3152 const char *cp = strchr (dname, '<');
3155 /* Do not compare the template part for template classes. */
3157 len = strlen (dname);
3160 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
3161 error (_("name of destructor must equal name of class"));
3168 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3169 class". If the name is found, return a value representing it;
3170 otherwise throw an exception. */
3172 static struct value *
3173 enum_constant_from_type (struct type *type, const char *name)
3176 int name_len = strlen (name);
3178 gdb_assert (TYPE_CODE (type) == TYPE_CODE_ENUM
3179 && TYPE_DECLARED_CLASS (type));
3181 for (i = TYPE_N_BASECLASSES (type); i < TYPE_NFIELDS (type); ++i)
3183 const char *fname = TYPE_FIELD_NAME (type, i);
3186 if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_ENUMVAL
3190 /* Look for the trailing "::NAME", since enum class constant
3191 names are qualified here. */
3192 len = strlen (fname);
3193 if (len + 2 >= name_len
3194 && fname[len - name_len - 2] == ':'
3195 && fname[len - name_len - 1] == ':'
3196 && strcmp (&fname[len - name_len], name) == 0)
3197 return value_from_longest (type, TYPE_FIELD_ENUMVAL (type, i));
3200 error (_("no constant named \"%s\" in enum \"%s\""),
3201 name, TYPE_TAG_NAME (type));
3204 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3205 return the appropriate member (or the address of the member, if
3206 WANT_ADDRESS). This function is used to resolve user expressions
3207 of the form "DOMAIN::NAME". For more details on what happens, see
3208 the comment before value_struct_elt_for_reference. */
3211 value_aggregate_elt (struct type *curtype, const char *name,
3212 struct type *expect_type, int want_address,
3215 switch (TYPE_CODE (curtype))
3217 case TYPE_CODE_STRUCT:
3218 case TYPE_CODE_UNION:
3219 return value_struct_elt_for_reference (curtype, 0, curtype,
3221 want_address, noside);
3222 case TYPE_CODE_NAMESPACE:
3223 return value_namespace_elt (curtype, name,
3224 want_address, noside);
3226 case TYPE_CODE_ENUM:
3227 return enum_constant_from_type (curtype, name);
3230 internal_error (__FILE__, __LINE__,
3231 _("non-aggregate type in value_aggregate_elt"));
3235 /* Compares the two method/function types T1 and T2 for "equality"
3236 with respect to the methods' parameters. If the types of the
3237 two parameter lists are the same, returns 1; 0 otherwise. This
3238 comparison may ignore any artificial parameters in T1 if
3239 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3240 the first artificial parameter in T1, assumed to be a 'this' pointer.
3242 The type T2 is expected to have come from make_params (in eval.c). */
3245 compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
3249 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
3252 /* If skipping artificial fields, find the first real field
3254 if (skip_artificial)
3256 while (start < TYPE_NFIELDS (t1)
3257 && TYPE_FIELD_ARTIFICIAL (t1, start))
3261 /* Now compare parameters. */
3263 /* Special case: a method taking void. T1 will contain no
3264 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3265 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1
3266 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID)
3269 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2))
3273 for (i = 0; i < TYPE_NFIELDS (t2); ++i)
3275 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i),
3276 TYPE_FIELD_TYPE (t2, i), NULL),
3277 EXACT_MATCH_BADNESS) != 0)
3287 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3288 return the address of this member as a "pointer to member" type.
3289 If INTYPE is non-null, then it will be the type of the member we
3290 are looking for. This will help us resolve "pointers to member
3291 functions". This function is used to resolve user expressions of
3292 the form "DOMAIN::NAME". */
3294 static struct value *
3295 value_struct_elt_for_reference (struct type *domain, int offset,
3296 struct type *curtype, const char *name,
3297 struct type *intype,
3301 struct type *t = curtype;
3303 struct value *v, *result;
3305 if (TYPE_CODE (t) != TYPE_CODE_STRUCT
3306 && TYPE_CODE (t) != TYPE_CODE_UNION)
3307 error (_("Internal error: non-aggregate type "
3308 "to value_struct_elt_for_reference"));
3310 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
3312 const char *t_field_name = TYPE_FIELD_NAME (t, i);
3314 if (t_field_name && strcmp (t_field_name, name) == 0)
3316 if (field_is_static (&TYPE_FIELD (t, i)))
3318 v = value_static_field (t, i);
3323 if (TYPE_FIELD_PACKED (t, i))
3324 error (_("pointers to bitfield members not allowed"));
3327 return value_from_longest
3328 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain),
3329 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
3330 else if (noside != EVAL_NORMAL)
3331 return allocate_value (TYPE_FIELD_TYPE (t, i));
3334 /* Try to evaluate NAME as a qualified name with implicit
3335 this pointer. In this case, attempt to return the
3336 equivalent to `this->*(&TYPE::NAME)'. */
3337 v = value_of_this_silent (current_language);
3342 struct type *type, *tmp;
3344 ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
3345 type = check_typedef (value_type (ptr));
3346 gdb_assert (type != NULL
3347 && TYPE_CODE (type) == TYPE_CODE_MEMBERPTR);
3348 tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
3349 v = value_cast_pointers (tmp, v, 1);
3350 mem_offset = value_as_long (ptr);
3351 tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
3352 result = value_from_pointer (tmp,
3353 value_as_long (v) + mem_offset);
3354 return value_ind (result);
3357 error (_("Cannot reference non-static field \"%s\""), name);
3362 /* C++: If it was not found as a data field, then try to return it
3363 as a pointer to a method. */
3365 /* Perform all necessary dereferencing. */
3366 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
3367 intype = TYPE_TARGET_TYPE (intype);
3369 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
3371 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
3372 char dem_opname[64];
3374 if (startswith (t_field_name, "__")
3375 || startswith (t_field_name, "op")
3376 || startswith (t_field_name, "type"))
3378 if (cplus_demangle_opname (t_field_name,
3379 dem_opname, DMGL_ANSI))
3380 t_field_name = dem_opname;
3381 else if (cplus_demangle_opname (t_field_name,
3383 t_field_name = dem_opname;
3385 if (t_field_name && strcmp (t_field_name, name) == 0)
3388 int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
3389 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
3391 check_stub_method_group (t, i);
3395 for (j = 0; j < len; ++j)
3397 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
3398 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
3404 error (_("no member function matches "
3405 "that type instantiation"));
3412 for (ii = 0; ii < len; ++ii)
3414 /* Skip artificial methods. This is necessary if,
3415 for example, the user wants to "print
3416 subclass::subclass" with only one user-defined
3417 constructor. There is no ambiguity in this case.
3418 We are careful here to allow artificial methods
3419 if they are the unique result. */
3420 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
3427 /* Desired method is ambiguous if more than one
3428 method is defined. */
3429 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
3430 error (_("non-unique member `%s' requires "
3431 "type instantiation"), name);
3437 error (_("no matching member function"));
3440 if (TYPE_FN_FIELD_STATIC_P (f, j))
3443 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3444 0, VAR_DOMAIN, 0).symbol;
3450 return value_addr (read_var_value (s, 0, 0));
3452 return read_var_value (s, 0, 0);
3455 if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
3459 result = allocate_value
3460 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3461 cplus_make_method_ptr (value_type (result),
3462 value_contents_writeable (result),
3463 TYPE_FN_FIELD_VOFFSET (f, j), 1);
3465 else if (noside == EVAL_AVOID_SIDE_EFFECTS)
3466 return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
3468 error (_("Cannot reference virtual member function \"%s\""),
3474 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
3475 0, VAR_DOMAIN, 0).symbol;
3480 v = read_var_value (s, 0, 0);
3485 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
3486 cplus_make_method_ptr (value_type (result),
3487 value_contents_writeable (result),
3488 value_address (v), 0);
3494 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
3499 if (BASETYPE_VIA_VIRTUAL (t, i))
3502 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
3503 v = value_struct_elt_for_reference (domain,
3504 offset + base_offset,
3505 TYPE_BASECLASS (t, i),
3507 want_address, noside);
3512 /* As a last chance, pretend that CURTYPE is a namespace, and look
3513 it up that way; this (frequently) works for types nested inside
3516 return value_maybe_namespace_elt (curtype, name,
3517 want_address, noside);
3520 /* C++: Return the member NAME of the namespace given by the type
3523 static struct value *
3524 value_namespace_elt (const struct type *curtype,
3525 const char *name, int want_address,
3528 struct value *retval = value_maybe_namespace_elt (curtype, name,
3533 error (_("No symbol \"%s\" in namespace \"%s\"."),
3534 name, TYPE_TAG_NAME (curtype));
3539 /* A helper function used by value_namespace_elt and
3540 value_struct_elt_for_reference. It looks up NAME inside the
3541 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
3542 is a class and NAME refers to a type in CURTYPE itself (as opposed
3543 to, say, some base class of CURTYPE). */
3545 static struct value *
3546 value_maybe_namespace_elt (const struct type *curtype,
3547 const char *name, int want_address,
3550 const char *namespace_name = TYPE_TAG_NAME (curtype);
3551 struct block_symbol sym;
3552 struct value *result;
3554 sym = cp_lookup_symbol_namespace (namespace_name, name,
3555 get_selected_block (0), VAR_DOMAIN);
3557 if (sym.symbol == NULL)
3559 else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
3560 && (SYMBOL_CLASS (sym.symbol) == LOC_TYPEDEF))
3561 result = allocate_value (SYMBOL_TYPE (sym.symbol));
3563 result = value_of_variable (sym.symbol, sym.block);
3566 result = value_addr (result);
3571 /* Given a pointer or a reference value V, find its real (RTTI) type.
3573 Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
3574 and refer to the values computed for the object pointed to. */
3577 value_rtti_indirect_type (struct value *v, int *full,
3578 int *top, int *using_enc)
3580 struct value *target = NULL;
3581 struct type *type, *real_type, *target_type;
3583 type = value_type (v);
3584 type = check_typedef (type);
3585 if (TYPE_CODE (type) == TYPE_CODE_REF)
3586 target = coerce_ref (v);
3587 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3592 target = value_ind (v);
3594 CATCH (except, RETURN_MASK_ERROR)
3596 if (except.error == MEMORY_ERROR)
3598 /* value_ind threw a memory error. The pointer is NULL or
3599 contains an uninitialized value: we can't determine any
3603 throw_exception (except);
3610 real_type = value_rtti_type (target, full, top, using_enc);
3614 /* Copy qualifiers to the referenced object. */
3615 target_type = value_type (target);
3616 real_type = make_cv_type (TYPE_CONST (target_type),
3617 TYPE_VOLATILE (target_type), real_type, NULL);
3618 if (TYPE_CODE (type) == TYPE_CODE_REF)
3619 real_type = lookup_reference_type (real_type);
3620 else if (TYPE_CODE (type) == TYPE_CODE_PTR)
3621 real_type = lookup_pointer_type (real_type);
3623 internal_error (__FILE__, __LINE__, _("Unexpected value type."));
3625 /* Copy qualifiers to the pointer/reference. */
3626 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
3633 /* Given a value pointed to by ARGP, check its real run-time type, and
3634 if that is different from the enclosing type, create a new value
3635 using the real run-time type as the enclosing type (and of the same
3636 type as ARGP) and return it, with the embedded offset adjusted to
3637 be the correct offset to the enclosed object. RTYPE is the type,
3638 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3639 by value_rtti_type(). If these are available, they can be supplied
3640 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3641 NULL if they're not available. */
3644 value_full_object (struct value *argp,
3646 int xfull, int xtop,
3649 struct type *real_type;
3653 struct value *new_val;
3660 using_enc = xusing_enc;
3663 real_type = value_rtti_type (argp, &full, &top, &using_enc);
3665 /* If no RTTI data, or if object is already complete, do nothing. */
3666 if (!real_type || real_type == value_enclosing_type (argp))
3669 /* In a destructor we might see a real type that is a superclass of
3670 the object's type. In this case it is better to leave the object
3673 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
3676 /* If we have the full object, but for some reason the enclosing
3677 type is wrong, set it. */
3678 /* pai: FIXME -- sounds iffy */
3681 argp = value_copy (argp);
3682 set_value_enclosing_type (argp, real_type);
3686 /* Check if object is in memory. */
3687 if (VALUE_LVAL (argp) != lval_memory)
3689 warning (_("Couldn't retrieve complete object of RTTI "
3690 "type %s; object may be in register(s)."),
3691 TYPE_NAME (real_type));
3696 /* All other cases -- retrieve the complete object. */
3697 /* Go back by the computed top_offset from the beginning of the
3698 object, adjusting for the embedded offset of argp if that's what
3699 value_rtti_type used for its computation. */
3700 new_val = value_at_lazy (real_type, value_address (argp) - top +
3701 (using_enc ? 0 : value_embedded_offset (argp)));
3702 deprecated_set_value_type (new_val, value_type (argp));
3703 set_value_embedded_offset (new_val, (using_enc
3704 ? top + value_embedded_offset (argp)
3710 /* Return the value of the local variable, if one exists. Throw error
3711 otherwise, such as if the request is made in an inappropriate context. */
3714 value_of_this (const struct language_defn *lang)
3716 struct block_symbol sym;
3717 const struct block *b;
3718 struct frame_info *frame;
3720 if (!lang->la_name_of_this)
3721 error (_("no `this' in current language"));
3723 frame = get_selected_frame (_("no frame selected"));
3725 b = get_frame_block (frame, NULL);
3727 sym = lookup_language_this (lang, b);
3728 if (sym.symbol == NULL)
3729 error (_("current stack frame does not contain a variable named `%s'"),
3730 lang->la_name_of_this);
3732 return read_var_value (sym.symbol, sym.block, frame);
3735 /* Return the value of the local variable, if one exists. Return NULL
3736 otherwise. Never throw error. */
3739 value_of_this_silent (const struct language_defn *lang)
3741 struct value *ret = NULL;
3745 ret = value_of_this (lang);
3747 CATCH (except, RETURN_MASK_ERROR)
3755 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3756 elements long, starting at LOWBOUND. The result has the same lower
3757 bound as the original ARRAY. */
3760 value_slice (struct value *array, int lowbound, int length)
3762 struct type *slice_range_type, *slice_type, *range_type;
3763 LONGEST lowerbound, upperbound;
3764 struct value *slice;
3765 struct type *array_type;
3767 array_type = check_typedef (value_type (array));
3768 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
3769 && TYPE_CODE (array_type) != TYPE_CODE_STRING)
3770 error (_("cannot take slice of non-array"));
3772 range_type = TYPE_INDEX_TYPE (array_type);
3773 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
3774 error (_("slice from bad array or bitstring"));
3776 if (lowbound < lowerbound || length < 0
3777 || lowbound + length - 1 > upperbound)
3778 error (_("slice out of range"));
3780 /* FIXME-type-allocation: need a way to free this type when we are
3782 slice_range_type = create_static_range_type ((struct type *) NULL,
3783 TYPE_TARGET_TYPE (range_type),
3785 lowbound + length - 1);
3788 struct type *element_type = TYPE_TARGET_TYPE (array_type);
3790 = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
3792 slice_type = create_array_type ((struct type *) NULL,
3795 TYPE_CODE (slice_type) = TYPE_CODE (array_type);
3797 if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
3798 slice = allocate_value_lazy (slice_type);
3801 slice = allocate_value (slice_type);
3802 value_contents_copy (slice, 0, array, offset,
3803 type_length_units (slice_type));
3806 set_value_component_location (slice, array);
3807 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array);
3808 set_value_offset (slice, value_offset (array) + offset);
3814 /* Create a value for a FORTRAN complex number. Currently most of the
3815 time values are coerced to COMPLEX*16 (i.e. a complex number
3816 composed of 2 doubles. This really should be a smarter routine
3817 that figures out precision inteligently as opposed to assuming
3818 doubles. FIXME: fmb */
3821 value_literal_complex (struct value *arg1,
3826 struct type *real_type = TYPE_TARGET_TYPE (type);
3828 val = allocate_value (type);
3829 arg1 = value_cast (real_type, arg1);
3830 arg2 = value_cast (real_type, arg2);
3832 memcpy (value_contents_raw (val),
3833 value_contents (arg1), TYPE_LENGTH (real_type));
3834 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type),
3835 value_contents (arg2), TYPE_LENGTH (real_type));
3839 /* Cast a value into the appropriate complex data type. */
3841 static struct value *
3842 cast_into_complex (struct type *type, struct value *val)
3844 struct type *real_type = TYPE_TARGET_TYPE (type);
3846 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX)
3848 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
3849 struct value *re_val = allocate_value (val_real_type);
3850 struct value *im_val = allocate_value (val_real_type);
3852 memcpy (value_contents_raw (re_val),
3853 value_contents (val), TYPE_LENGTH (val_real_type));
3854 memcpy (value_contents_raw (im_val),
3855 value_contents (val) + TYPE_LENGTH (val_real_type),
3856 TYPE_LENGTH (val_real_type));
3858 return value_literal_complex (re_val, im_val, type);
3860 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT
3861 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
3862 return value_literal_complex (val,
3863 value_zero (real_type, not_lval),
3866 error (_("cannot cast non-number to complex"));
3870 _initialize_valops (void)
3872 add_setshow_boolean_cmd ("overload-resolution", class_support,
3873 &overload_resolution, _("\
3874 Set overload resolution in evaluating C++ functions."), _("\
3875 Show overload resolution in evaluating C++ functions."),
3877 show_overload_resolution,
3878 &setlist, &showlist);
3879 overload_resolution = 1;