1 /* Perform non-arithmetic operations on values, for GDB.
3 Copyright (C) 1986-2020 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"
37 #include "target-float.h"
38 #include "tracepoint.h"
39 #include "observable.h"
41 #include "extension.h"
43 #include "gdbsupport/byte-vector.h"
45 /* Local functions. */
47 static int typecmp (int staticp
, int varargs
, int nargs
,
48 struct field t1
[], struct value
*t2
[]);
50 static struct value
*search_struct_field (const char *, struct value
*,
53 static struct value
*search_struct_method (const char *, struct value
**,
55 LONGEST
, int *, struct type
*);
57 static int find_oload_champ_namespace (gdb::array_view
<value
*> args
,
58 const char *, const char *,
59 std::vector
<symbol
*> *oload_syms
,
63 static int find_oload_champ_namespace_loop (gdb::array_view
<value
*> args
,
64 const char *, const char *,
65 int, std::vector
<symbol
*> *oload_syms
,
66 badness_vector
*, int *,
69 static int find_oload_champ (gdb::array_view
<value
*> args
,
72 xmethod_worker_up
*xmethods
,
74 badness_vector
*oload_champ_bv
);
76 static int oload_method_static_p (struct fn_field
*, int);
78 enum oload_classification
{ STANDARD
, NON_STANDARD
, INCOMPATIBLE
};
80 static enum oload_classification classify_oload_match
81 (const badness_vector
&, int, int);
83 static struct value
*value_struct_elt_for_reference (struct type
*,
89 static struct value
*value_namespace_elt (const struct type
*,
90 const char *, int , enum noside
);
92 static struct value
*value_maybe_namespace_elt (const struct type
*,
96 static CORE_ADDR
allocate_space_in_inferior (int);
98 static struct value
*cast_into_complex (struct type
*, struct value
*);
100 bool overload_resolution
= false;
102 show_overload_resolution (struct ui_file
*file
, int from_tty
,
103 struct cmd_list_element
*c
,
106 fprintf_filtered (file
, _("Overload resolution in evaluating "
107 "C++ functions is %s.\n"),
111 /* Find the address of function name NAME in the inferior. If OBJF_P
112 is non-NULL, *OBJF_P will be set to the OBJFILE where the function
116 find_function_in_inferior (const char *name
, struct objfile
**objf_p
)
118 struct block_symbol sym
;
120 sym
= lookup_symbol (name
, 0, VAR_DOMAIN
, 0);
121 if (sym
.symbol
!= NULL
)
123 if (SYMBOL_CLASS (sym
.symbol
) != LOC_BLOCK
)
125 error (_("\"%s\" exists in this program but is not a function."),
130 *objf_p
= symbol_objfile (sym
.symbol
);
132 return value_of_variable (sym
.symbol
, sym
.block
);
136 struct bound_minimal_symbol msymbol
=
137 lookup_bound_minimal_symbol (name
);
139 if (msymbol
.minsym
!= NULL
)
141 struct objfile
*objfile
= msymbol
.objfile
;
142 struct gdbarch
*gdbarch
= objfile
->arch ();
146 type
= lookup_pointer_type (builtin_type (gdbarch
)->builtin_char
);
147 type
= lookup_function_type (type
);
148 type
= lookup_pointer_type (type
);
149 maddr
= BMSYMBOL_VALUE_ADDRESS (msymbol
);
154 return value_from_pointer (type
, maddr
);
158 if (!target_has_execution
)
159 error (_("evaluation of this expression "
160 "requires the target program to be active"));
162 error (_("evaluation of this expression requires the "
163 "program to have a function \"%s\"."),
169 /* Allocate NBYTES of space in the inferior using the inferior's
170 malloc and return a value that is a pointer to the allocated
174 value_allocate_space_in_inferior (int len
)
176 struct objfile
*objf
;
177 struct value
*val
= find_function_in_inferior ("malloc", &objf
);
178 struct gdbarch
*gdbarch
= objf
->arch ();
179 struct value
*blocklen
;
181 blocklen
= value_from_longest (builtin_type (gdbarch
)->builtin_int
, len
);
182 val
= call_function_by_hand (val
, NULL
, blocklen
);
183 if (value_logical_not (val
))
185 if (!target_has_execution
)
186 error (_("No memory available to program now: "
187 "you need to start the target first"));
189 error (_("No memory available to program: call to malloc failed"));
195 allocate_space_in_inferior (int len
)
197 return value_as_long (value_allocate_space_in_inferior (len
));
200 /* Cast struct value VAL to type TYPE and return as a value.
201 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
202 for this to work. Typedef to one of the codes is permitted.
203 Returns NULL if the cast is neither an upcast nor a downcast. */
205 static struct value
*
206 value_cast_structs (struct type
*type
, struct value
*v2
)
212 gdb_assert (type
!= NULL
&& v2
!= NULL
);
214 t1
= check_typedef (type
);
215 t2
= check_typedef (value_type (v2
));
217 /* Check preconditions. */
218 gdb_assert ((t1
->code () == TYPE_CODE_STRUCT
219 || t1
->code () == TYPE_CODE_UNION
)
220 && !!"Precondition is that type is of STRUCT or UNION kind.");
221 gdb_assert ((t2
->code () == TYPE_CODE_STRUCT
222 || t2
->code () == TYPE_CODE_UNION
)
223 && !!"Precondition is that value is of STRUCT or UNION kind");
225 if (t1
->name () != NULL
226 && t2
->name () != NULL
227 && !strcmp (t1
->name (), t2
->name ()))
230 /* Upcasting: look in the type of the source to see if it contains the
231 type of the target as a superclass. If so, we'll need to
232 offset the pointer rather than just change its type. */
233 if (t1
->name () != NULL
)
235 v
= search_struct_field (t1
->name (),
241 /* Downcasting: look in the type of the target to see if it contains the
242 type of the source as a superclass. If so, we'll need to
243 offset the pointer rather than just change its type. */
244 if (t2
->name () != NULL
)
246 /* Try downcasting using the run-time type of the value. */
249 struct type
*real_type
;
251 real_type
= value_rtti_type (v2
, &full
, &top
, &using_enc
);
254 v
= value_full_object (v2
, real_type
, full
, top
, using_enc
);
255 v
= value_at_lazy (real_type
, value_address (v
));
256 real_type
= value_type (v
);
258 /* We might be trying to cast to the outermost enclosing
259 type, in which case search_struct_field won't work. */
260 if (real_type
->name () != NULL
261 && !strcmp (real_type
->name (), t1
->name ()))
264 v
= search_struct_field (t2
->name (), v
, real_type
, 1);
269 /* Try downcasting using information from the destination type
270 T2. This wouldn't work properly for classes with virtual
271 bases, but those were handled above. */
272 v
= search_struct_field (t2
->name (),
273 value_zero (t1
, not_lval
), t1
, 1);
276 /* Downcasting is possible (t1 is superclass of v2). */
277 CORE_ADDR addr2
= value_address (v2
);
279 addr2
-= value_address (v
) + value_embedded_offset (v
);
280 return value_at (type
, addr2
);
287 /* Cast one pointer or reference type to another. Both TYPE and
288 the type of ARG2 should be pointer types, or else both should be
289 reference types. If SUBCLASS_CHECK is non-zero, this will force a
290 check to see whether TYPE is a superclass of ARG2's type. If
291 SUBCLASS_CHECK is zero, then the subclass check is done only when
292 ARG2 is itself non-zero. Returns the new pointer or reference. */
295 value_cast_pointers (struct type
*type
, struct value
*arg2
,
298 struct type
*type1
= check_typedef (type
);
299 struct type
*type2
= check_typedef (value_type (arg2
));
300 struct type
*t1
= check_typedef (TYPE_TARGET_TYPE (type1
));
301 struct type
*t2
= check_typedef (TYPE_TARGET_TYPE (type2
));
303 if (t1
->code () == TYPE_CODE_STRUCT
304 && t2
->code () == TYPE_CODE_STRUCT
305 && (subclass_check
|| !value_logical_not (arg2
)))
309 if (TYPE_IS_REFERENCE (type2
))
310 v2
= coerce_ref (arg2
);
312 v2
= value_ind (arg2
);
313 gdb_assert (check_typedef (value_type (v2
))->code ()
314 == TYPE_CODE_STRUCT
&& !!"Why did coercion fail?");
315 v2
= value_cast_structs (t1
, v2
);
316 /* At this point we have what we can have, un-dereference if needed. */
319 struct value
*v
= value_addr (v2
);
321 deprecated_set_value_type (v
, type
);
326 /* No superclass found, just change the pointer type. */
327 arg2
= value_copy (arg2
);
328 deprecated_set_value_type (arg2
, type
);
329 set_value_enclosing_type (arg2
, type
);
330 set_value_pointed_to_offset (arg2
, 0); /* pai: chk_val */
334 /* Cast value ARG2 to type TYPE and return as a value.
335 More general than a C cast: accepts any two types of the same length,
336 and if ARG2 is an lvalue it can be cast into anything at all. */
337 /* In C++, casts may change pointer or object representations. */
340 value_cast (struct type
*type
, struct value
*arg2
)
342 enum type_code code1
;
343 enum type_code code2
;
347 int convert_to_boolean
= 0;
349 if (value_type (arg2
) == type
)
352 /* Check if we are casting struct reference to struct reference. */
353 if (TYPE_IS_REFERENCE (check_typedef (type
)))
355 /* We dereference type; then we recurse and finally
356 we generate value of the given reference. Nothing wrong with
358 struct type
*t1
= check_typedef (type
);
359 struct type
*dereftype
= check_typedef (TYPE_TARGET_TYPE (t1
));
360 struct value
*val
= value_cast (dereftype
, arg2
);
362 return value_ref (val
, t1
->code ());
365 if (TYPE_IS_REFERENCE (check_typedef (value_type (arg2
))))
366 /* We deref the value and then do the cast. */
367 return value_cast (type
, coerce_ref (arg2
));
369 /* Strip typedefs / resolve stubs in order to get at the type's
370 code/length, but remember the original type, to use as the
371 resulting type of the cast, in case it was a typedef. */
372 struct type
*to_type
= type
;
374 type
= check_typedef (type
);
375 code1
= type
->code ();
376 arg2
= coerce_ref (arg2
);
377 type2
= check_typedef (value_type (arg2
));
379 /* You can't cast to a reference type. See value_cast_pointers
381 gdb_assert (!TYPE_IS_REFERENCE (type
));
383 /* A cast to an undetermined-length array_type, such as
384 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
385 where N is sizeof(OBJECT)/sizeof(TYPE). */
386 if (code1
== TYPE_CODE_ARRAY
)
388 struct type
*element_type
= TYPE_TARGET_TYPE (type
);
389 unsigned element_length
= TYPE_LENGTH (check_typedef (element_type
));
391 if (element_length
> 0 && type
->bounds ()->high
.kind () == PROP_UNDEFINED
)
393 struct type
*range_type
= type
->index_type ();
394 int val_length
= TYPE_LENGTH (type2
);
395 LONGEST low_bound
, high_bound
, new_length
;
397 if (get_discrete_bounds (range_type
, &low_bound
, &high_bound
) < 0)
398 low_bound
= 0, high_bound
= 0;
399 new_length
= val_length
/ element_length
;
400 if (val_length
% element_length
!= 0)
401 warning (_("array element type size does not "
402 "divide object size in cast"));
403 /* FIXME-type-allocation: need a way to free this type when
404 we are done with it. */
405 range_type
= create_static_range_type (NULL
,
406 TYPE_TARGET_TYPE (range_type
),
408 new_length
+ low_bound
- 1);
409 deprecated_set_value_type (arg2
,
410 create_array_type (NULL
,
417 if (current_language
->c_style_arrays_p ()
418 && type2
->code () == TYPE_CODE_ARRAY
419 && !type2
->is_vector ())
420 arg2
= value_coerce_array (arg2
);
422 if (type2
->code () == TYPE_CODE_FUNC
)
423 arg2
= value_coerce_function (arg2
);
425 type2
= check_typedef (value_type (arg2
));
426 code2
= type2
->code ();
428 if (code1
== TYPE_CODE_COMPLEX
)
429 return cast_into_complex (to_type
, arg2
);
430 if (code1
== TYPE_CODE_BOOL
)
432 code1
= TYPE_CODE_INT
;
433 convert_to_boolean
= 1;
435 if (code1
== TYPE_CODE_CHAR
)
436 code1
= TYPE_CODE_INT
;
437 if (code2
== TYPE_CODE_BOOL
|| code2
== TYPE_CODE_CHAR
)
438 code2
= TYPE_CODE_INT
;
440 scalar
= (code2
== TYPE_CODE_INT
|| code2
== TYPE_CODE_FLT
441 || code2
== TYPE_CODE_DECFLOAT
|| code2
== TYPE_CODE_ENUM
442 || code2
== TYPE_CODE_RANGE
);
444 if ((code1
== TYPE_CODE_STRUCT
|| code1
== TYPE_CODE_UNION
)
445 && (code2
== TYPE_CODE_STRUCT
|| code2
== TYPE_CODE_UNION
)
446 && type
->name () != 0)
448 struct value
*v
= value_cast_structs (to_type
, arg2
);
454 if (is_floating_type (type
) && scalar
)
456 if (is_floating_value (arg2
))
458 struct value
*v
= allocate_value (to_type
);
459 target_float_convert (value_contents (arg2
), type2
,
460 value_contents_raw (v
), type
);
464 /* The only option left is an integral type. */
465 if (type2
->is_unsigned ())
466 return value_from_ulongest (to_type
, value_as_long (arg2
));
468 return value_from_longest (to_type
, value_as_long (arg2
));
470 else if ((code1
== TYPE_CODE_INT
|| code1
== TYPE_CODE_ENUM
471 || code1
== TYPE_CODE_RANGE
)
472 && (scalar
|| code2
== TYPE_CODE_PTR
473 || code2
== TYPE_CODE_MEMBERPTR
))
477 /* When we cast pointers to integers, we mustn't use
478 gdbarch_pointer_to_address to find the address the pointer
479 represents, as value_as_long would. GDB should evaluate
480 expressions just as the compiler would --- and the compiler
481 sees a cast as a simple reinterpretation of the pointer's
483 if (code2
== TYPE_CODE_PTR
)
484 longest
= extract_unsigned_integer
485 (value_contents (arg2
), TYPE_LENGTH (type2
),
486 type_byte_order (type2
));
488 longest
= value_as_long (arg2
);
489 return value_from_longest (to_type
, convert_to_boolean
?
490 (LONGEST
) (longest
? 1 : 0) : longest
);
492 else if (code1
== TYPE_CODE_PTR
&& (code2
== TYPE_CODE_INT
493 || code2
== TYPE_CODE_ENUM
494 || code2
== TYPE_CODE_RANGE
))
496 /* TYPE_LENGTH (type) is the length of a pointer, but we really
497 want the length of an address! -- we are really dealing with
498 addresses (i.e., gdb representations) not pointers (i.e.,
499 target representations) here.
501 This allows things like "print *(int *)0x01000234" to work
502 without printing a misleading message -- which would
503 otherwise occur when dealing with a target having two byte
504 pointers and four byte addresses. */
506 int addr_bit
= gdbarch_addr_bit (get_type_arch (type2
));
507 LONGEST longest
= value_as_long (arg2
);
509 if (addr_bit
< sizeof (LONGEST
) * HOST_CHAR_BIT
)
511 if (longest
>= ((LONGEST
) 1 << addr_bit
)
512 || longest
<= -((LONGEST
) 1 << addr_bit
))
513 warning (_("value truncated"));
515 return value_from_longest (to_type
, longest
);
517 else if (code1
== TYPE_CODE_METHODPTR
&& code2
== TYPE_CODE_INT
518 && value_as_long (arg2
) == 0)
520 struct value
*result
= allocate_value (to_type
);
522 cplus_make_method_ptr (to_type
, value_contents_writeable (result
), 0, 0);
525 else if (code1
== TYPE_CODE_MEMBERPTR
&& code2
== TYPE_CODE_INT
526 && value_as_long (arg2
) == 0)
528 /* The Itanium C++ ABI represents NULL pointers to members as
529 minus one, instead of biasing the normal case. */
530 return value_from_longest (to_type
, -1);
532 else if (code1
== TYPE_CODE_ARRAY
&& type
->is_vector ()
533 && code2
== TYPE_CODE_ARRAY
&& type2
->is_vector ()
534 && TYPE_LENGTH (type
) != TYPE_LENGTH (type2
))
535 error (_("Cannot convert between vector values of different sizes"));
536 else if (code1
== TYPE_CODE_ARRAY
&& type
->is_vector () && scalar
537 && TYPE_LENGTH (type
) != TYPE_LENGTH (type2
))
538 error (_("can only cast scalar to vector of same size"));
539 else if (code1
== TYPE_CODE_VOID
)
541 return value_zero (to_type
, not_lval
);
543 else if (TYPE_LENGTH (type
) == TYPE_LENGTH (type2
))
545 if (code1
== TYPE_CODE_PTR
&& code2
== TYPE_CODE_PTR
)
546 return value_cast_pointers (to_type
, arg2
, 0);
548 arg2
= value_copy (arg2
);
549 deprecated_set_value_type (arg2
, to_type
);
550 set_value_enclosing_type (arg2
, to_type
);
551 set_value_pointed_to_offset (arg2
, 0); /* pai: chk_val */
554 else if (VALUE_LVAL (arg2
) == lval_memory
)
555 return value_at_lazy (to_type
, value_address (arg2
));
558 if (current_language
->la_language
== language_ada
)
559 error (_("Invalid type conversion."));
560 error (_("Invalid cast."));
564 /* The C++ reinterpret_cast operator. */
567 value_reinterpret_cast (struct type
*type
, struct value
*arg
)
569 struct value
*result
;
570 struct type
*real_type
= check_typedef (type
);
571 struct type
*arg_type
, *dest_type
;
573 enum type_code dest_code
, arg_code
;
575 /* Do reference, function, and array conversion. */
576 arg
= coerce_array (arg
);
578 /* Attempt to preserve the type the user asked for. */
581 /* If we are casting to a reference type, transform
582 reinterpret_cast<T&[&]>(V) to *reinterpret_cast<T*>(&V). */
583 if (TYPE_IS_REFERENCE (real_type
))
586 arg
= value_addr (arg
);
587 dest_type
= lookup_pointer_type (TYPE_TARGET_TYPE (dest_type
));
588 real_type
= lookup_pointer_type (real_type
);
591 arg_type
= value_type (arg
);
593 dest_code
= real_type
->code ();
594 arg_code
= arg_type
->code ();
596 /* We can convert pointer types, or any pointer type to int, or int
598 if ((dest_code
== TYPE_CODE_PTR
&& arg_code
== TYPE_CODE_INT
)
599 || (dest_code
== TYPE_CODE_INT
&& arg_code
== TYPE_CODE_PTR
)
600 || (dest_code
== TYPE_CODE_METHODPTR
&& arg_code
== TYPE_CODE_INT
)
601 || (dest_code
== TYPE_CODE_INT
&& arg_code
== TYPE_CODE_METHODPTR
)
602 || (dest_code
== TYPE_CODE_MEMBERPTR
&& arg_code
== TYPE_CODE_INT
)
603 || (dest_code
== TYPE_CODE_INT
&& arg_code
== TYPE_CODE_MEMBERPTR
)
604 || (dest_code
== arg_code
605 && (dest_code
== TYPE_CODE_PTR
606 || dest_code
== TYPE_CODE_METHODPTR
607 || dest_code
== TYPE_CODE_MEMBERPTR
)))
608 result
= value_cast (dest_type
, arg
);
610 error (_("Invalid reinterpret_cast"));
613 result
= value_cast (type
, value_ref (value_ind (result
),
619 /* A helper for value_dynamic_cast. This implements the first of two
620 runtime checks: we iterate over all the base classes of the value's
621 class which are equal to the desired class; if only one of these
622 holds the value, then it is the answer. */
625 dynamic_cast_check_1 (struct type
*desired_type
,
626 const gdb_byte
*valaddr
,
627 LONGEST embedded_offset
,
630 struct type
*search_type
,
632 struct type
*arg_type
,
633 struct value
**result
)
635 int i
, result_count
= 0;
637 for (i
= 0; i
< TYPE_N_BASECLASSES (search_type
) && result_count
< 2; ++i
)
639 LONGEST offset
= baseclass_offset (search_type
, i
, valaddr
,
643 if (class_types_same_p (desired_type
, TYPE_BASECLASS (search_type
, i
)))
645 if (address
+ embedded_offset
+ offset
>= arg_addr
646 && address
+ embedded_offset
+ offset
< arg_addr
+ TYPE_LENGTH (arg_type
))
650 *result
= value_at_lazy (TYPE_BASECLASS (search_type
, i
),
651 address
+ embedded_offset
+ offset
);
655 result_count
+= dynamic_cast_check_1 (desired_type
,
657 embedded_offset
+ offset
,
659 TYPE_BASECLASS (search_type
, i
),
668 /* A helper for value_dynamic_cast. This implements the second of two
669 runtime checks: we look for a unique public sibling class of the
670 argument's declared class. */
673 dynamic_cast_check_2 (struct type
*desired_type
,
674 const gdb_byte
*valaddr
,
675 LONGEST embedded_offset
,
678 struct type
*search_type
,
679 struct value
**result
)
681 int i
, result_count
= 0;
683 for (i
= 0; i
< TYPE_N_BASECLASSES (search_type
) && result_count
< 2; ++i
)
687 if (! BASETYPE_VIA_PUBLIC (search_type
, i
))
690 offset
= baseclass_offset (search_type
, i
, valaddr
, embedded_offset
,
692 if (class_types_same_p (desired_type
, TYPE_BASECLASS (search_type
, i
)))
696 *result
= value_at_lazy (TYPE_BASECLASS (search_type
, i
),
697 address
+ embedded_offset
+ offset
);
700 result_count
+= dynamic_cast_check_2 (desired_type
,
702 embedded_offset
+ offset
,
704 TYPE_BASECLASS (search_type
, i
),
711 /* The C++ dynamic_cast operator. */
714 value_dynamic_cast (struct type
*type
, struct value
*arg
)
718 struct type
*resolved_type
= check_typedef (type
);
719 struct type
*arg_type
= check_typedef (value_type (arg
));
720 struct type
*class_type
, *rtti_type
;
721 struct value
*result
, *tem
, *original_arg
= arg
;
723 int is_ref
= TYPE_IS_REFERENCE (resolved_type
);
725 if (resolved_type
->code () != TYPE_CODE_PTR
726 && !TYPE_IS_REFERENCE (resolved_type
))
727 error (_("Argument to dynamic_cast must be a pointer or reference type"));
728 if (TYPE_TARGET_TYPE (resolved_type
)->code () != TYPE_CODE_VOID
729 && TYPE_TARGET_TYPE (resolved_type
)->code () != TYPE_CODE_STRUCT
)
730 error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
732 class_type
= check_typedef (TYPE_TARGET_TYPE (resolved_type
));
733 if (resolved_type
->code () == TYPE_CODE_PTR
)
735 if (arg_type
->code () != TYPE_CODE_PTR
736 && ! (arg_type
->code () == TYPE_CODE_INT
737 && value_as_long (arg
) == 0))
738 error (_("Argument to dynamic_cast does not have pointer type"));
739 if (arg_type
->code () == TYPE_CODE_PTR
)
741 arg_type
= check_typedef (TYPE_TARGET_TYPE (arg_type
));
742 if (arg_type
->code () != TYPE_CODE_STRUCT
)
743 error (_("Argument to dynamic_cast does "
744 "not have pointer to class type"));
747 /* Handle NULL pointers. */
748 if (value_as_long (arg
) == 0)
749 return value_zero (type
, not_lval
);
751 arg
= value_ind (arg
);
755 if (arg_type
->code () != TYPE_CODE_STRUCT
)
756 error (_("Argument to dynamic_cast does not have class type"));
759 /* If the classes are the same, just return the argument. */
760 if (class_types_same_p (class_type
, arg_type
))
761 return value_cast (type
, arg
);
763 /* If the target type is a unique base class of the argument's
764 declared type, just cast it. */
765 if (is_ancestor (class_type
, arg_type
))
767 if (is_unique_ancestor (class_type
, arg
))
768 return value_cast (type
, original_arg
);
769 error (_("Ambiguous dynamic_cast"));
772 rtti_type
= value_rtti_type (arg
, &full
, &top
, &using_enc
);
774 error (_("Couldn't determine value's most derived type for dynamic_cast"));
776 /* Compute the most derived object's address. */
777 addr
= value_address (arg
);
785 addr
+= top
+ value_embedded_offset (arg
);
787 /* dynamic_cast<void *> means to return a pointer to the
788 most-derived object. */
789 if (resolved_type
->code () == TYPE_CODE_PTR
790 && TYPE_TARGET_TYPE (resolved_type
)->code () == TYPE_CODE_VOID
)
791 return value_at_lazy (type
, addr
);
793 tem
= value_at (type
, addr
);
794 type
= value_type (tem
);
796 /* The first dynamic check specified in 5.2.7. */
797 if (is_public_ancestor (arg_type
, TYPE_TARGET_TYPE (resolved_type
)))
799 if (class_types_same_p (rtti_type
, TYPE_TARGET_TYPE (resolved_type
)))
802 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type
),
803 value_contents_for_printing (tem
),
804 value_embedded_offset (tem
),
805 value_address (tem
), tem
,
809 return value_cast (type
,
811 ? value_ref (result
, resolved_type
->code ())
812 : value_addr (result
));
815 /* The second dynamic check specified in 5.2.7. */
817 if (is_public_ancestor (arg_type
, rtti_type
)
818 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type
),
819 value_contents_for_printing (tem
),
820 value_embedded_offset (tem
),
821 value_address (tem
), tem
,
822 rtti_type
, &result
) == 1)
823 return value_cast (type
,
825 ? value_ref (result
, resolved_type
->code ())
826 : value_addr (result
));
828 if (resolved_type
->code () == TYPE_CODE_PTR
)
829 return value_zero (type
, not_lval
);
831 error (_("dynamic_cast failed"));
834 /* Create a value of type TYPE that is zero, and return it. */
837 value_zero (struct type
*type
, enum lval_type lv
)
839 struct value
*val
= allocate_value (type
);
841 VALUE_LVAL (val
) = (lv
== lval_computed
? not_lval
: lv
);
845 /* Create a not_lval value of numeric type TYPE that is one, and return it. */
848 value_one (struct type
*type
)
850 struct type
*type1
= check_typedef (type
);
853 if (is_integral_type (type1
) || is_floating_type (type1
))
855 val
= value_from_longest (type
, (LONGEST
) 1);
857 else if (type1
->code () == TYPE_CODE_ARRAY
&& type1
->is_vector ())
859 struct type
*eltype
= check_typedef (TYPE_TARGET_TYPE (type1
));
861 LONGEST low_bound
, high_bound
;
864 if (!get_array_bounds (type1
, &low_bound
, &high_bound
))
865 error (_("Could not determine the vector bounds"));
867 val
= allocate_value (type
);
868 for (i
= 0; i
< high_bound
- low_bound
+ 1; i
++)
870 tmp
= value_one (eltype
);
871 memcpy (value_contents_writeable (val
) + i
* TYPE_LENGTH (eltype
),
872 value_contents_all (tmp
), TYPE_LENGTH (eltype
));
877 error (_("Not a numeric type."));
880 /* value_one result is never used for assignments to. */
881 gdb_assert (VALUE_LVAL (val
) == not_lval
);
886 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
887 The type of the created value may differ from the passed type TYPE.
888 Make sure to retrieve the returned values's new type after this call
889 e.g. in case the type is a variable length array. */
891 static struct value
*
892 get_value_at (struct type
*type
, CORE_ADDR addr
, int lazy
)
896 if (check_typedef (type
)->code () == TYPE_CODE_VOID
)
897 error (_("Attempt to dereference a generic pointer."));
899 val
= value_from_contents_and_address (type
, NULL
, addr
);
902 value_fetch_lazy (val
);
907 /* Return a value with type TYPE located at ADDR.
909 Call value_at only if the data needs to be fetched immediately;
910 if we can be 'lazy' and defer the fetch, perhaps indefinitely, call
911 value_at_lazy instead. value_at_lazy simply records the address of
912 the data and sets the lazy-evaluation-required flag. The lazy flag
913 is tested in the value_contents macro, which is used if and when
914 the contents are actually required. The type of the created value
915 may differ from the passed type TYPE. Make sure to retrieve the
916 returned values's new type after this call e.g. in case the type
917 is a variable length array.
919 Note: value_at does *NOT* handle embedded offsets; perform such
920 adjustments before or after calling it. */
923 value_at (struct type
*type
, CORE_ADDR addr
)
925 return get_value_at (type
, addr
, 0);
928 /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
929 The type of the created value may differ from the passed type TYPE.
930 Make sure to retrieve the returned values's new type after this call
931 e.g. in case the type is a variable length array. */
934 value_at_lazy (struct type
*type
, CORE_ADDR addr
)
936 return get_value_at (type
, addr
, 1);
940 read_value_memory (struct value
*val
, LONGEST bit_offset
,
941 int stack
, CORE_ADDR memaddr
,
942 gdb_byte
*buffer
, size_t length
)
944 ULONGEST xfered_total
= 0;
945 struct gdbarch
*arch
= get_value_arch (val
);
946 int unit_size
= gdbarch_addressable_memory_unit_size (arch
);
947 enum target_object object
;
949 object
= stack
? TARGET_OBJECT_STACK_MEMORY
: TARGET_OBJECT_MEMORY
;
951 while (xfered_total
< length
)
953 enum target_xfer_status status
;
954 ULONGEST xfered_partial
;
956 status
= target_xfer_partial (current_top_target (),
958 buffer
+ xfered_total
* unit_size
, NULL
,
959 memaddr
+ xfered_total
,
960 length
- xfered_total
,
963 if (status
== TARGET_XFER_OK
)
965 else if (status
== TARGET_XFER_UNAVAILABLE
)
966 mark_value_bits_unavailable (val
, (xfered_total
* HOST_CHAR_BIT
968 xfered_partial
* HOST_CHAR_BIT
);
969 else if (status
== TARGET_XFER_EOF
)
970 memory_error (TARGET_XFER_E_IO
, memaddr
+ xfered_total
);
972 memory_error (status
, memaddr
+ xfered_total
);
974 xfered_total
+= xfered_partial
;
979 /* Store the contents of FROMVAL into the location of TOVAL.
980 Return a new value with the location of TOVAL and contents of FROMVAL. */
983 value_assign (struct value
*toval
, struct value
*fromval
)
987 struct frame_id old_frame
;
989 if (!deprecated_value_modifiable (toval
))
990 error (_("Left operand of assignment is not a modifiable lvalue."));
992 toval
= coerce_ref (toval
);
994 type
= value_type (toval
);
995 if (VALUE_LVAL (toval
) != lval_internalvar
)
996 fromval
= value_cast (type
, fromval
);
999 /* Coerce arrays and functions to pointers, except for arrays
1000 which only live in GDB's storage. */
1001 if (!value_must_coerce_to_target (fromval
))
1002 fromval
= coerce_array (fromval
);
1005 type
= check_typedef (type
);
1007 /* Since modifying a register can trash the frame chain, and
1008 modifying memory can trash the frame cache, we save the old frame
1009 and then restore the new frame afterwards. */
1010 old_frame
= get_frame_id (deprecated_safe_get_selected_frame ());
1012 switch (VALUE_LVAL (toval
))
1014 case lval_internalvar
:
1015 set_internalvar (VALUE_INTERNALVAR (toval
), fromval
);
1016 return value_of_internalvar (get_type_arch (type
),
1017 VALUE_INTERNALVAR (toval
));
1019 case lval_internalvar_component
:
1021 LONGEST offset
= value_offset (toval
);
1023 /* Are we dealing with a bitfield?
1025 It is important to mention that `value_parent (toval)' is
1026 non-NULL iff `value_bitsize (toval)' is non-zero. */
1027 if (value_bitsize (toval
))
1029 /* VALUE_INTERNALVAR below refers to the parent value, while
1030 the offset is relative to this parent value. */
1031 gdb_assert (value_parent (value_parent (toval
)) == NULL
);
1032 offset
+= value_offset (value_parent (toval
));
1035 set_internalvar_component (VALUE_INTERNALVAR (toval
),
1037 value_bitpos (toval
),
1038 value_bitsize (toval
),
1045 const gdb_byte
*dest_buffer
;
1046 CORE_ADDR changed_addr
;
1048 gdb_byte buffer
[sizeof (LONGEST
)];
1050 if (value_bitsize (toval
))
1052 struct value
*parent
= value_parent (toval
);
1054 changed_addr
= value_address (parent
) + value_offset (toval
);
1055 changed_len
= (value_bitpos (toval
)
1056 + value_bitsize (toval
)
1057 + HOST_CHAR_BIT
- 1)
1060 /* If we can read-modify-write exactly the size of the
1061 containing type (e.g. short or int) then do so. This
1062 is safer for volatile bitfields mapped to hardware
1064 if (changed_len
< TYPE_LENGTH (type
)
1065 && TYPE_LENGTH (type
) <= (int) sizeof (LONGEST
)
1066 && ((LONGEST
) changed_addr
% TYPE_LENGTH (type
)) == 0)
1067 changed_len
= TYPE_LENGTH (type
);
1069 if (changed_len
> (int) sizeof (LONGEST
))
1070 error (_("Can't handle bitfields which "
1071 "don't fit in a %d bit word."),
1072 (int) sizeof (LONGEST
) * HOST_CHAR_BIT
);
1074 read_memory (changed_addr
, buffer
, changed_len
);
1075 modify_field (type
, buffer
, value_as_long (fromval
),
1076 value_bitpos (toval
), value_bitsize (toval
));
1077 dest_buffer
= buffer
;
1081 changed_addr
= value_address (toval
);
1082 changed_len
= type_length_units (type
);
1083 dest_buffer
= value_contents (fromval
);
1086 write_memory_with_notification (changed_addr
, dest_buffer
, changed_len
);
1092 struct frame_info
*frame
;
1093 struct gdbarch
*gdbarch
;
1096 /* Figure out which frame this is in currently.
1098 We use VALUE_FRAME_ID for obtaining the value's frame id instead of
1099 VALUE_NEXT_FRAME_ID due to requiring a frame which may be passed to
1100 put_frame_register_bytes() below. That function will (eventually)
1101 perform the necessary unwind operation by first obtaining the next
1103 frame
= frame_find_by_id (VALUE_FRAME_ID (toval
));
1105 value_reg
= VALUE_REGNUM (toval
);
1108 error (_("Value being assigned to is no longer active."));
1110 gdbarch
= get_frame_arch (frame
);
1112 if (value_bitsize (toval
))
1114 struct value
*parent
= value_parent (toval
);
1115 LONGEST offset
= value_offset (parent
) + value_offset (toval
);
1117 gdb_byte buffer
[sizeof (LONGEST
)];
1120 changed_len
= (value_bitpos (toval
)
1121 + value_bitsize (toval
)
1122 + HOST_CHAR_BIT
- 1)
1125 if (changed_len
> (int) sizeof (LONGEST
))
1126 error (_("Can't handle bitfields which "
1127 "don't fit in a %d bit word."),
1128 (int) sizeof (LONGEST
) * HOST_CHAR_BIT
);
1130 if (!get_frame_register_bytes (frame
, value_reg
, offset
,
1131 changed_len
, buffer
,
1135 throw_error (OPTIMIZED_OUT_ERROR
,
1136 _("value has been optimized out"));
1138 throw_error (NOT_AVAILABLE_ERROR
,
1139 _("value is not available"));
1142 modify_field (type
, buffer
, value_as_long (fromval
),
1143 value_bitpos (toval
), value_bitsize (toval
));
1145 put_frame_register_bytes (frame
, value_reg
, offset
,
1146 changed_len
, buffer
);
1150 if (gdbarch_convert_register_p (gdbarch
, VALUE_REGNUM (toval
),
1153 /* If TOVAL is a special machine register requiring
1154 conversion of program values to a special raw
1156 gdbarch_value_to_register (gdbarch
, frame
,
1157 VALUE_REGNUM (toval
), type
,
1158 value_contents (fromval
));
1162 put_frame_register_bytes (frame
, value_reg
,
1163 value_offset (toval
),
1165 value_contents (fromval
));
1169 gdb::observers::register_changed
.notify (frame
, value_reg
);
1175 const struct lval_funcs
*funcs
= value_computed_funcs (toval
);
1177 if (funcs
->write
!= NULL
)
1179 funcs
->write (toval
, fromval
);
1186 error (_("Left operand of assignment is not an lvalue."));
1189 /* Assigning to the stack pointer, frame pointer, and other
1190 (architecture and calling convention specific) registers may
1191 cause the frame cache and regcache to be out of date. Assigning to memory
1192 also can. We just do this on all assignments to registers or
1193 memory, for simplicity's sake; I doubt the slowdown matters. */
1194 switch (VALUE_LVAL (toval
))
1200 gdb::observers::target_changed
.notify (current_top_target ());
1202 /* Having destroyed the frame cache, restore the selected
1205 /* FIXME: cagney/2002-11-02: There has to be a better way of
1206 doing this. Instead of constantly saving/restoring the
1207 frame. Why not create a get_selected_frame() function that,
1208 having saved the selected frame's ID can automatically
1209 re-find the previously selected frame automatically. */
1212 struct frame_info
*fi
= frame_find_by_id (old_frame
);
1223 /* If the field does not entirely fill a LONGEST, then zero the sign
1224 bits. If the field is signed, and is negative, then sign
1226 if ((value_bitsize (toval
) > 0)
1227 && (value_bitsize (toval
) < 8 * (int) sizeof (LONGEST
)))
1229 LONGEST fieldval
= value_as_long (fromval
);
1230 LONGEST valmask
= (((ULONGEST
) 1) << value_bitsize (toval
)) - 1;
1232 fieldval
&= valmask
;
1233 if (!type
->is_unsigned ()
1234 && (fieldval
& (valmask
^ (valmask
>> 1))))
1235 fieldval
|= ~valmask
;
1237 fromval
= value_from_longest (type
, fieldval
);
1240 /* The return value is a copy of TOVAL so it shares its location
1241 information, but its contents are updated from FROMVAL. This
1242 implies the returned value is not lazy, even if TOVAL was. */
1243 val
= value_copy (toval
);
1244 set_value_lazy (val
, 0);
1245 memcpy (value_contents_raw (val
), value_contents (fromval
),
1246 TYPE_LENGTH (type
));
1248 /* We copy over the enclosing type and pointed-to offset from FROMVAL
1249 in the case of pointer types. For object types, the enclosing type
1250 and embedded offset must *not* be copied: the target object refered
1251 to by TOVAL retains its original dynamic type after assignment. */
1252 if (type
->code () == TYPE_CODE_PTR
)
1254 set_value_enclosing_type (val
, value_enclosing_type (fromval
));
1255 set_value_pointed_to_offset (val
, value_pointed_to_offset (fromval
));
1261 /* Extend a value ARG1 to COUNT repetitions of its type. */
1264 value_repeat (struct value
*arg1
, int count
)
1268 if (VALUE_LVAL (arg1
) != lval_memory
)
1269 error (_("Only values in memory can be extended with '@'."));
1271 error (_("Invalid number %d of repetitions."), count
);
1273 val
= allocate_repeat_value (value_enclosing_type (arg1
), count
);
1275 VALUE_LVAL (val
) = lval_memory
;
1276 set_value_address (val
, value_address (arg1
));
1278 read_value_memory (val
, 0, value_stack (val
), value_address (val
),
1279 value_contents_all_raw (val
),
1280 type_length_units (value_enclosing_type (val
)));
1286 value_of_variable (struct symbol
*var
, const struct block
*b
)
1288 struct frame_info
*frame
= NULL
;
1290 if (symbol_read_needs_frame (var
))
1291 frame
= get_selected_frame (_("No frame selected."));
1293 return read_var_value (var
, b
, frame
);
1297 address_of_variable (struct symbol
*var
, const struct block
*b
)
1299 struct type
*type
= SYMBOL_TYPE (var
);
1302 /* Evaluate it first; if the result is a memory address, we're fine.
1303 Lazy evaluation pays off here. */
1305 val
= value_of_variable (var
, b
);
1306 type
= value_type (val
);
1308 if ((VALUE_LVAL (val
) == lval_memory
&& value_lazy (val
))
1309 || type
->code () == TYPE_CODE_FUNC
)
1311 CORE_ADDR addr
= value_address (val
);
1313 return value_from_pointer (lookup_pointer_type (type
), addr
);
1316 /* Not a memory address; check what the problem was. */
1317 switch (VALUE_LVAL (val
))
1321 struct frame_info
*frame
;
1322 const char *regname
;
1324 frame
= frame_find_by_id (VALUE_NEXT_FRAME_ID (val
));
1327 regname
= gdbarch_register_name (get_frame_arch (frame
),
1328 VALUE_REGNUM (val
));
1329 gdb_assert (regname
&& *regname
);
1331 error (_("Address requested for identifier "
1332 "\"%s\" which is in register $%s"),
1333 var
->print_name (), regname
);
1338 error (_("Can't take address of \"%s\" which isn't an lvalue."),
1339 var
->print_name ());
1349 value_must_coerce_to_target (struct value
*val
)
1351 struct type
*valtype
;
1353 /* The only lval kinds which do not live in target memory. */
1354 if (VALUE_LVAL (val
) != not_lval
1355 && VALUE_LVAL (val
) != lval_internalvar
1356 && VALUE_LVAL (val
) != lval_xcallable
)
1359 valtype
= check_typedef (value_type (val
));
1361 switch (valtype
->code ())
1363 case TYPE_CODE_ARRAY
:
1364 return valtype
->is_vector () ? 0 : 1;
1365 case TYPE_CODE_STRING
:
1372 /* Make sure that VAL lives in target memory if it's supposed to. For
1373 instance, strings are constructed as character arrays in GDB's
1374 storage, and this function copies them to the target. */
1377 value_coerce_to_target (struct value
*val
)
1382 if (!value_must_coerce_to_target (val
))
1385 length
= TYPE_LENGTH (check_typedef (value_type (val
)));
1386 addr
= allocate_space_in_inferior (length
);
1387 write_memory (addr
, value_contents (val
), length
);
1388 return value_at_lazy (value_type (val
), addr
);
1391 /* Given a value which is an array, return a value which is a pointer
1392 to its first element, regardless of whether or not the array has a
1393 nonzero lower bound.
1395 FIXME: A previous comment here indicated that this routine should
1396 be substracting the array's lower bound. It's not clear to me that
1397 this is correct. Given an array subscripting operation, it would
1398 certainly work to do the adjustment here, essentially computing:
1400 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
1402 However I believe a more appropriate and logical place to account
1403 for the lower bound is to do so in value_subscript, essentially
1406 (&array[0] + ((index - lowerbound) * sizeof array[0]))
1408 As further evidence consider what would happen with operations
1409 other than array subscripting, where the caller would get back a
1410 value that had an address somewhere before the actual first element
1411 of the array, and the information about the lower bound would be
1412 lost because of the coercion to pointer type. */
1415 value_coerce_array (struct value
*arg1
)
1417 struct type
*type
= check_typedef (value_type (arg1
));
1419 /* If the user tries to do something requiring a pointer with an
1420 array that has not yet been pushed to the target, then this would
1421 be a good time to do so. */
1422 arg1
= value_coerce_to_target (arg1
);
1424 if (VALUE_LVAL (arg1
) != lval_memory
)
1425 error (_("Attempt to take address of value not located in memory."));
1427 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type
)),
1428 value_address (arg1
));
1431 /* Given a value which is a function, return a value which is a pointer
1435 value_coerce_function (struct value
*arg1
)
1437 struct value
*retval
;
1439 if (VALUE_LVAL (arg1
) != lval_memory
)
1440 error (_("Attempt to take address of value not located in memory."));
1442 retval
= value_from_pointer (lookup_pointer_type (value_type (arg1
)),
1443 value_address (arg1
));
1447 /* Return a pointer value for the object for which ARG1 is the
1451 value_addr (struct value
*arg1
)
1454 struct type
*type
= check_typedef (value_type (arg1
));
1456 if (TYPE_IS_REFERENCE (type
))
1458 if (value_bits_synthetic_pointer (arg1
, value_embedded_offset (arg1
),
1459 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
1460 arg1
= coerce_ref (arg1
);
1463 /* Copy the value, but change the type from (T&) to (T*). We
1464 keep the same location information, which is efficient, and
1465 allows &(&X) to get the location containing the reference.
1466 Do the same to its enclosing type for consistency. */
1467 struct type
*type_ptr
1468 = lookup_pointer_type (TYPE_TARGET_TYPE (type
));
1469 struct type
*enclosing_type
1470 = check_typedef (value_enclosing_type (arg1
));
1471 struct type
*enclosing_type_ptr
1472 = lookup_pointer_type (TYPE_TARGET_TYPE (enclosing_type
));
1474 arg2
= value_copy (arg1
);
1475 deprecated_set_value_type (arg2
, type_ptr
);
1476 set_value_enclosing_type (arg2
, enclosing_type_ptr
);
1481 if (type
->code () == TYPE_CODE_FUNC
)
1482 return value_coerce_function (arg1
);
1484 /* If this is an array that has not yet been pushed to the target,
1485 then this would be a good time to force it to memory. */
1486 arg1
= value_coerce_to_target (arg1
);
1488 if (VALUE_LVAL (arg1
) != lval_memory
)
1489 error (_("Attempt to take address of value not located in memory."));
1491 /* Get target memory address. */
1492 arg2
= value_from_pointer (lookup_pointer_type (value_type (arg1
)),
1493 (value_address (arg1
)
1494 + value_embedded_offset (arg1
)));
1496 /* This may be a pointer to a base subobject; so remember the
1497 full derived object's type ... */
1498 set_value_enclosing_type (arg2
,
1499 lookup_pointer_type (value_enclosing_type (arg1
)));
1500 /* ... and also the relative position of the subobject in the full
1502 set_value_pointed_to_offset (arg2
, value_embedded_offset (arg1
));
1506 /* Return a reference value for the object for which ARG1 is the
1510 value_ref (struct value
*arg1
, enum type_code refcode
)
1513 struct type
*type
= check_typedef (value_type (arg1
));
1515 gdb_assert (refcode
== TYPE_CODE_REF
|| refcode
== TYPE_CODE_RVALUE_REF
);
1517 if ((type
->code () == TYPE_CODE_REF
1518 || type
->code () == TYPE_CODE_RVALUE_REF
)
1519 && type
->code () == refcode
)
1522 arg2
= value_addr (arg1
);
1523 deprecated_set_value_type (arg2
, lookup_reference_type (type
, refcode
));
1527 /* Given a value of a pointer type, apply the C unary * operator to
1531 value_ind (struct value
*arg1
)
1533 struct type
*base_type
;
1536 arg1
= coerce_array (arg1
);
1538 base_type
= check_typedef (value_type (arg1
));
1540 if (VALUE_LVAL (arg1
) == lval_computed
)
1542 const struct lval_funcs
*funcs
= value_computed_funcs (arg1
);
1544 if (funcs
->indirect
)
1546 struct value
*result
= funcs
->indirect (arg1
);
1553 if (base_type
->code () == TYPE_CODE_PTR
)
1555 struct type
*enc_type
;
1557 /* We may be pointing to something embedded in a larger object.
1558 Get the real type of the enclosing object. */
1559 enc_type
= check_typedef (value_enclosing_type (arg1
));
1560 enc_type
= TYPE_TARGET_TYPE (enc_type
);
1562 CORE_ADDR base_addr
;
1563 if (check_typedef (enc_type
)->code () == TYPE_CODE_FUNC
1564 || check_typedef (enc_type
)->code () == TYPE_CODE_METHOD
)
1566 /* For functions, go through find_function_addr, which knows
1567 how to handle function descriptors. */
1568 base_addr
= find_function_addr (arg1
, NULL
);
1572 /* Retrieve the enclosing object pointed to. */
1573 base_addr
= (value_as_address (arg1
)
1574 - value_pointed_to_offset (arg1
));
1576 arg2
= value_at_lazy (enc_type
, base_addr
);
1577 enc_type
= value_type (arg2
);
1578 return readjust_indirect_value_type (arg2
, enc_type
, base_type
,
1582 error (_("Attempt to take contents of a non-pointer value."));
1585 /* Create a value for an array by allocating space in GDB, copying the
1586 data into that space, and then setting up an array value.
1588 The array bounds are set from LOWBOUND and HIGHBOUND, and the array
1589 is populated from the values passed in ELEMVEC.
1591 The element type of the array is inherited from the type of the
1592 first element, and all elements must have the same size (though we
1593 don't currently enforce any restriction on their types). */
1596 value_array (int lowbound
, int highbound
, struct value
**elemvec
)
1600 ULONGEST typelength
;
1602 struct type
*arraytype
;
1604 /* Validate that the bounds are reasonable and that each of the
1605 elements have the same size. */
1607 nelem
= highbound
- lowbound
+ 1;
1610 error (_("bad array bounds (%d, %d)"), lowbound
, highbound
);
1612 typelength
= type_length_units (value_enclosing_type (elemvec
[0]));
1613 for (idx
= 1; idx
< nelem
; idx
++)
1615 if (type_length_units (value_enclosing_type (elemvec
[idx
]))
1618 error (_("array elements must all be the same size"));
1622 arraytype
= lookup_array_range_type (value_enclosing_type (elemvec
[0]),
1623 lowbound
, highbound
);
1625 if (!current_language
->c_style_arrays_p ())
1627 val
= allocate_value (arraytype
);
1628 for (idx
= 0; idx
< nelem
; idx
++)
1629 value_contents_copy (val
, idx
* typelength
, elemvec
[idx
], 0,
1634 /* Allocate space to store the array, and then initialize it by
1635 copying in each element. */
1637 val
= allocate_value (arraytype
);
1638 for (idx
= 0; idx
< nelem
; idx
++)
1639 value_contents_copy (val
, idx
* typelength
, elemvec
[idx
], 0, typelength
);
1644 value_cstring (const char *ptr
, ssize_t len
, struct type
*char_type
)
1647 int lowbound
= current_language
->string_lower_bound ();
1648 ssize_t highbound
= len
/ TYPE_LENGTH (char_type
);
1649 struct type
*stringtype
1650 = lookup_array_range_type (char_type
, lowbound
, highbound
+ lowbound
- 1);
1652 val
= allocate_value (stringtype
);
1653 memcpy (value_contents_raw (val
), ptr
, len
);
1657 /* Create a value for a string constant by allocating space in the
1658 inferior, copying the data into that space, and returning the
1659 address with type TYPE_CODE_STRING. PTR points to the string
1660 constant data; LEN is number of characters.
1662 Note that string types are like array of char types with a lower
1663 bound of zero and an upper bound of LEN - 1. Also note that the
1664 string may contain embedded null bytes. */
1667 value_string (const char *ptr
, ssize_t len
, struct type
*char_type
)
1670 int lowbound
= current_language
->string_lower_bound ();
1671 ssize_t highbound
= len
/ TYPE_LENGTH (char_type
);
1672 struct type
*stringtype
1673 = lookup_string_range_type (char_type
, lowbound
, highbound
+ lowbound
- 1);
1675 val
= allocate_value (stringtype
);
1676 memcpy (value_contents_raw (val
), ptr
, len
);
1681 /* See if we can pass arguments in T2 to a function which takes
1682 arguments of types T1. T1 is a list of NARGS arguments, and T2 is
1683 a NULL-terminated vector. If some arguments need coercion of some
1684 sort, then the coerced values are written into T2. Return value is
1685 0 if the arguments could be matched, or the position at which they
1688 STATICP is nonzero if the T1 argument list came from a static
1689 member function. T2 will still include the ``this'' pointer, but
1692 For non-static member functions, we ignore the first argument,
1693 which is the type of the instance variable. This is because we
1694 want to handle calls with objects from derived classes. This is
1695 not entirely correct: we should actually check to make sure that a
1696 requested operation is type secure, shouldn't we? FIXME. */
1699 typecmp (int staticp
, int varargs
, int nargs
,
1700 struct field t1
[], struct value
*t2
[])
1705 internal_error (__FILE__
, __LINE__
,
1706 _("typecmp: no argument list"));
1708 /* Skip ``this'' argument if applicable. T2 will always include
1714 (i
< nargs
) && t1
[i
].type ()->code () != TYPE_CODE_VOID
;
1717 struct type
*tt1
, *tt2
;
1722 tt1
= check_typedef (t1
[i
].type ());
1723 tt2
= check_typedef (value_type (t2
[i
]));
1725 if (TYPE_IS_REFERENCE (tt1
)
1726 /* We should be doing hairy argument matching, as below. */
1727 && (check_typedef (TYPE_TARGET_TYPE (tt1
))->code ()
1730 if (tt2
->code () == TYPE_CODE_ARRAY
)
1731 t2
[i
] = value_coerce_array (t2
[i
]);
1733 t2
[i
] = value_ref (t2
[i
], tt1
->code ());
1737 /* djb - 20000715 - Until the new type structure is in the
1738 place, and we can attempt things like implicit conversions,
1739 we need to do this so you can take something like a map<const
1740 char *>, and properly access map["hello"], because the
1741 argument to [] will be a reference to a pointer to a char,
1742 and the argument will be a pointer to a char. */
1743 while (TYPE_IS_REFERENCE (tt1
) || tt1
->code () == TYPE_CODE_PTR
)
1745 tt1
= check_typedef ( TYPE_TARGET_TYPE (tt1
) );
1747 while (tt2
->code () == TYPE_CODE_ARRAY
1748 || tt2
->code () == TYPE_CODE_PTR
1749 || TYPE_IS_REFERENCE (tt2
))
1751 tt2
= check_typedef (TYPE_TARGET_TYPE (tt2
));
1753 if (tt1
->code () == tt2
->code ())
1755 /* Array to pointer is a `trivial conversion' according to the
1758 /* We should be doing much hairier argument matching (see
1759 section 13.2 of the ARM), but as a quick kludge, just check
1760 for the same type code. */
1761 if (t1
[i
].type ()->code () != value_type (t2
[i
])->code ())
1764 if (varargs
|| t2
[i
] == NULL
)
1769 /* Helper class for do_search_struct_field that updates *RESULT_PTR
1770 and *LAST_BOFFSET, and possibly throws an exception if the field
1771 search has yielded ambiguous results. */
1774 update_search_result (struct value
**result_ptr
, struct value
*v
,
1775 LONGEST
*last_boffset
, LONGEST boffset
,
1776 const char *name
, struct type
*type
)
1780 if (*result_ptr
!= NULL
1781 /* The result is not ambiguous if all the classes that are
1782 found occupy the same space. */
1783 && *last_boffset
!= boffset
)
1784 error (_("base class '%s' is ambiguous in type '%s'"),
1785 name
, TYPE_SAFE_NAME (type
));
1787 *last_boffset
= boffset
;
1791 /* A helper for search_struct_field. This does all the work; most
1792 arguments are as passed to search_struct_field. The result is
1793 stored in *RESULT_PTR, which must be initialized to NULL.
1794 OUTERMOST_TYPE is the type of the initial type passed to
1795 search_struct_field; this is used for error reporting when the
1796 lookup is ambiguous. */
1799 do_search_struct_field (const char *name
, struct value
*arg1
, LONGEST offset
,
1800 struct type
*type
, int looking_for_baseclass
,
1801 struct value
**result_ptr
,
1802 LONGEST
*last_boffset
,
1803 struct type
*outermost_type
)
1808 type
= check_typedef (type
);
1809 nbases
= TYPE_N_BASECLASSES (type
);
1811 if (!looking_for_baseclass
)
1812 for (i
= type
->num_fields () - 1; i
>= nbases
; i
--)
1814 const char *t_field_name
= TYPE_FIELD_NAME (type
, i
);
1816 if (t_field_name
&& (strcmp_iw (t_field_name
, name
) == 0))
1820 if (field_is_static (&type
->field (i
)))
1821 v
= value_static_field (type
, i
);
1823 v
= value_primitive_field (arg1
, offset
, i
, type
);
1829 && t_field_name
[0] == '\0')
1831 struct type
*field_type
= type
->field (i
).type ();
1833 if (field_type
->code () == TYPE_CODE_UNION
1834 || field_type
->code () == TYPE_CODE_STRUCT
)
1836 /* Look for a match through the fields of an anonymous
1837 union, or anonymous struct. C++ provides anonymous
1840 In the GNU Chill (now deleted from GDB)
1841 implementation of variant record types, each
1842 <alternative field> has an (anonymous) union type,
1843 each member of the union represents a <variant
1844 alternative>. Each <variant alternative> is
1845 represented as a struct, with a member for each
1848 struct value
*v
= NULL
;
1849 LONGEST new_offset
= offset
;
1851 /* This is pretty gross. In G++, the offset in an
1852 anonymous union is relative to the beginning of the
1853 enclosing struct. In the GNU Chill (now deleted
1854 from GDB) implementation of variant records, the
1855 bitpos is zero in an anonymous union field, so we
1856 have to add the offset of the union here. */
1857 if (field_type
->code () == TYPE_CODE_STRUCT
1858 || (field_type
->num_fields () > 0
1859 && TYPE_FIELD_BITPOS (field_type
, 0) == 0))
1860 new_offset
+= TYPE_FIELD_BITPOS (type
, i
) / 8;
1862 do_search_struct_field (name
, arg1
, new_offset
,
1864 looking_for_baseclass
, &v
,
1876 for (i
= 0; i
< nbases
; i
++)
1878 struct value
*v
= NULL
;
1879 struct type
*basetype
= check_typedef (TYPE_BASECLASS (type
, i
));
1880 /* If we are looking for baseclasses, this is what we get when
1881 we hit them. But it could happen that the base part's member
1882 name is not yet filled in. */
1883 int found_baseclass
= (looking_for_baseclass
1884 && TYPE_BASECLASS_NAME (type
, i
) != NULL
1885 && (strcmp_iw (name
,
1886 TYPE_BASECLASS_NAME (type
,
1888 LONGEST boffset
= value_embedded_offset (arg1
) + offset
;
1890 if (BASETYPE_VIA_VIRTUAL (type
, i
))
1894 boffset
= baseclass_offset (type
, i
,
1895 value_contents_for_printing (arg1
),
1896 value_embedded_offset (arg1
) + offset
,
1897 value_address (arg1
),
1900 /* The virtual base class pointer might have been clobbered
1901 by the user program. Make sure that it still points to a
1902 valid memory location. */
1904 boffset
+= value_embedded_offset (arg1
) + offset
;
1906 || boffset
>= TYPE_LENGTH (value_enclosing_type (arg1
)))
1908 CORE_ADDR base_addr
;
1910 base_addr
= value_address (arg1
) + boffset
;
1911 v2
= value_at_lazy (basetype
, base_addr
);
1912 if (target_read_memory (base_addr
,
1913 value_contents_raw (v2
),
1914 TYPE_LENGTH (value_type (v2
))) != 0)
1915 error (_("virtual baseclass botch"));
1919 v2
= value_copy (arg1
);
1920 deprecated_set_value_type (v2
, basetype
);
1921 set_value_embedded_offset (v2
, boffset
);
1924 if (found_baseclass
)
1928 do_search_struct_field (name
, v2
, 0,
1929 TYPE_BASECLASS (type
, i
),
1930 looking_for_baseclass
,
1931 result_ptr
, last_boffset
,
1935 else if (found_baseclass
)
1936 v
= value_primitive_field (arg1
, offset
, i
, type
);
1939 do_search_struct_field (name
, arg1
,
1940 offset
+ TYPE_BASECLASS_BITPOS (type
,
1942 basetype
, looking_for_baseclass
,
1943 result_ptr
, last_boffset
,
1947 update_search_result (result_ptr
, v
, last_boffset
,
1948 boffset
, name
, outermost_type
);
1952 /* Helper function used by value_struct_elt to recurse through
1953 baseclasses. Look for a field NAME in ARG1. Search in it assuming
1954 it has (class) type TYPE. If found, return value, else return NULL.
1956 If LOOKING_FOR_BASECLASS, then instead of looking for struct
1957 fields, look for a baseclass named NAME. */
1959 static struct value
*
1960 search_struct_field (const char *name
, struct value
*arg1
,
1961 struct type
*type
, int looking_for_baseclass
)
1963 struct value
*result
= NULL
;
1964 LONGEST boffset
= 0;
1966 do_search_struct_field (name
, arg1
, 0, type
, looking_for_baseclass
,
1967 &result
, &boffset
, type
);
1971 /* Helper function used by value_struct_elt to recurse through
1972 baseclasses. Look for a field NAME in ARG1. Adjust the address of
1973 ARG1 by OFFSET bytes, and search in it assuming it has (class) type
1976 If found, return value, else if name matched and args not return
1977 (value) -1, else return NULL. */
1979 static struct value
*
1980 search_struct_method (const char *name
, struct value
**arg1p
,
1981 struct value
**args
, LONGEST offset
,
1982 int *static_memfuncp
, struct type
*type
)
1986 int name_matched
= 0;
1988 type
= check_typedef (type
);
1989 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; i
--)
1991 const char *t_field_name
= TYPE_FN_FIELDLIST_NAME (type
, i
);
1993 if (t_field_name
&& (strcmp_iw (t_field_name
, name
) == 0))
1995 int j
= TYPE_FN_FIELDLIST_LENGTH (type
, i
) - 1;
1996 struct fn_field
*f
= TYPE_FN_FIELDLIST1 (type
, i
);
1999 check_stub_method_group (type
, i
);
2000 if (j
> 0 && args
== 0)
2001 error (_("cannot resolve overloaded method "
2002 "`%s': no arguments supplied"), name
);
2003 else if (j
== 0 && args
== 0)
2005 v
= value_fn_field (arg1p
, f
, j
, type
, offset
);
2012 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f
, j
),
2013 TYPE_FN_FIELD_TYPE (f
, j
)->has_varargs (),
2014 TYPE_FN_FIELD_TYPE (f
, j
)->num_fields (),
2015 TYPE_FN_FIELD_ARGS (f
, j
), args
))
2017 if (TYPE_FN_FIELD_VIRTUAL_P (f
, j
))
2018 return value_virtual_fn_field (arg1p
, f
, j
,
2020 if (TYPE_FN_FIELD_STATIC_P (f
, j
)
2022 *static_memfuncp
= 1;
2023 v
= value_fn_field (arg1p
, f
, j
, type
, offset
);
2032 for (i
= TYPE_N_BASECLASSES (type
) - 1; i
>= 0; i
--)
2034 LONGEST base_offset
;
2035 LONGEST this_offset
;
2037 if (BASETYPE_VIA_VIRTUAL (type
, i
))
2039 struct type
*baseclass
= check_typedef (TYPE_BASECLASS (type
, i
));
2040 struct value
*base_val
;
2041 const gdb_byte
*base_valaddr
;
2043 /* The virtual base class pointer might have been
2044 clobbered by the user program. Make sure that it
2045 still points to a valid memory location. */
2047 if (offset
< 0 || offset
>= TYPE_LENGTH (type
))
2051 gdb::byte_vector
tmp (TYPE_LENGTH (baseclass
));
2052 address
= value_address (*arg1p
);
2054 if (target_read_memory (address
+ offset
,
2055 tmp
.data (), 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
);
2067 base_valaddr
= value_contents_for_printing (*arg1p
);
2068 this_offset
= offset
;
2071 base_offset
= baseclass_offset (type
, i
, base_valaddr
,
2072 this_offset
, value_address (base_val
),
2077 base_offset
= TYPE_BASECLASS_BITPOS (type
, i
) / 8;
2079 v
= search_struct_method (name
, arg1p
, args
, base_offset
+ offset
,
2080 static_memfuncp
, TYPE_BASECLASS (type
, i
));
2081 if (v
== (struct value
*) - 1)
2087 /* FIXME-bothner: Why is this commented out? Why is it here? */
2088 /* *arg1p = arg1_tmp; */
2093 return (struct value
*) - 1;
2098 /* Given *ARGP, a value of type (pointer to a)* structure/union,
2099 extract the component named NAME from the ultimate target
2100 structure/union and return it as a value with its appropriate type.
2101 ERR is used in the error message if *ARGP's type is wrong.
2103 C++: ARGS is a list of argument types to aid in the selection of
2104 an appropriate method. Also, handle derived types.
2106 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
2107 where the truthvalue of whether the function that was resolved was
2108 a static member function or not is stored.
2110 ERR is an error message to be printed in case the field is not
2114 value_struct_elt (struct value
**argp
, struct value
**args
,
2115 const char *name
, int *static_memfuncp
, const char *err
)
2120 *argp
= coerce_array (*argp
);
2122 t
= check_typedef (value_type (*argp
));
2124 /* Follow pointers until we get to a non-pointer. */
2126 while (t
->code () == TYPE_CODE_PTR
|| TYPE_IS_REFERENCE (t
))
2128 *argp
= value_ind (*argp
);
2129 /* Don't coerce fn pointer to fn and then back again! */
2130 if (check_typedef (value_type (*argp
))->code () != TYPE_CODE_FUNC
)
2131 *argp
= coerce_array (*argp
);
2132 t
= check_typedef (value_type (*argp
));
2135 if (t
->code () != TYPE_CODE_STRUCT
2136 && t
->code () != TYPE_CODE_UNION
)
2137 error (_("Attempt to extract a component of a value that is not a %s."),
2140 /* Assume it's not, unless we see that it is. */
2141 if (static_memfuncp
)
2142 *static_memfuncp
= 0;
2146 /* if there are no arguments ...do this... */
2148 /* Try as a field first, because if we succeed, there is less
2150 v
= search_struct_field (name
, *argp
, t
, 0);
2154 /* C++: If it was not found as a data field, then try to
2155 return it as a pointer to a method. */
2156 v
= search_struct_method (name
, argp
, args
, 0,
2157 static_memfuncp
, t
);
2159 if (v
== (struct value
*) - 1)
2160 error (_("Cannot take address of method %s."), name
);
2163 if (TYPE_NFN_FIELDS (t
))
2164 error (_("There is no member or method named %s."), name
);
2166 error (_("There is no member named %s."), name
);
2171 v
= search_struct_method (name
, argp
, args
, 0,
2172 static_memfuncp
, t
);
2174 if (v
== (struct value
*) - 1)
2176 error (_("One of the arguments you tried to pass to %s could not "
2177 "be converted to what the function wants."), name
);
2181 /* See if user tried to invoke data as function. If so, hand it
2182 back. If it's not callable (i.e., a pointer to function),
2183 gdb should give an error. */
2184 v
= search_struct_field (name
, *argp
, t
, 0);
2185 /* If we found an ordinary field, then it is not a method call.
2186 So, treat it as if it were a static member function. */
2187 if (v
&& static_memfuncp
)
2188 *static_memfuncp
= 1;
2192 throw_error (NOT_FOUND_ERROR
,
2193 _("Structure has no component named %s."), name
);
2197 /* Given *ARGP, a value of type structure or union, or a pointer/reference
2198 to a structure or union, extract and return its component (field) of
2199 type FTYPE at the specified BITPOS.
2200 Throw an exception on error. */
2203 value_struct_elt_bitpos (struct value
**argp
, int bitpos
, struct type
*ftype
,
2209 *argp
= coerce_array (*argp
);
2211 t
= check_typedef (value_type (*argp
));
2213 while (t
->code () == TYPE_CODE_PTR
|| TYPE_IS_REFERENCE (t
))
2215 *argp
= value_ind (*argp
);
2216 if (check_typedef (value_type (*argp
))->code () != TYPE_CODE_FUNC
)
2217 *argp
= coerce_array (*argp
);
2218 t
= check_typedef (value_type (*argp
));
2221 if (t
->code () != TYPE_CODE_STRUCT
2222 && t
->code () != TYPE_CODE_UNION
)
2223 error (_("Attempt to extract a component of a value that is not a %s."),
2226 for (i
= TYPE_N_BASECLASSES (t
); i
< t
->num_fields (); i
++)
2228 if (!field_is_static (&t
->field (i
))
2229 && bitpos
== TYPE_FIELD_BITPOS (t
, i
)
2230 && types_equal (ftype
, t
->field (i
).type ()))
2231 return value_primitive_field (*argp
, 0, i
, t
);
2234 error (_("No field with matching bitpos and type."));
2240 /* Search through the methods of an object (and its bases) to find a
2241 specified method. Return a reference to the fn_field list METHODS of
2242 overloaded instances defined in the source language. If available
2243 and matching, a vector of matching xmethods defined in extension
2244 languages are also returned in XMETHODS.
2246 Helper function for value_find_oload_list.
2247 ARGP is a pointer to a pointer to a value (the object).
2248 METHOD is a string containing the method name.
2249 OFFSET is the offset within the value.
2250 TYPE is the assumed type of the object.
2251 METHODS is a pointer to the matching overloaded instances defined
2252 in the source language. Since this is a recursive function,
2253 *METHODS should be set to NULL when calling this function.
2254 NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
2255 0 when calling this function.
2256 XMETHODS is the vector of matching xmethod workers. *XMETHODS
2257 should also be set to NULL when calling this function.
2258 BASETYPE is set to the actual type of the subobject where the
2260 BOFFSET is the offset of the base subobject where the method is found. */
2263 find_method_list (struct value
**argp
, const char *method
,
2264 LONGEST offset
, struct type
*type
,
2265 gdb::array_view
<fn_field
> *methods
,
2266 std::vector
<xmethod_worker_up
> *xmethods
,
2267 struct type
**basetype
, LONGEST
*boffset
)
2270 struct fn_field
*f
= NULL
;
2272 gdb_assert (methods
!= NULL
&& xmethods
!= NULL
);
2273 type
= check_typedef (type
);
2275 /* First check in object itself.
2276 This function is called recursively to search through base classes.
2277 If there is a source method match found at some stage, then we need not
2278 look for source methods in consequent recursive calls. */
2279 if (methods
->empty ())
2281 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; i
--)
2283 /* pai: FIXME What about operators and type conversions? */
2284 const char *fn_field_name
= TYPE_FN_FIELDLIST_NAME (type
, i
);
2286 if (fn_field_name
&& (strcmp_iw (fn_field_name
, method
) == 0))
2288 int len
= TYPE_FN_FIELDLIST_LENGTH (type
, i
);
2289 f
= TYPE_FN_FIELDLIST1 (type
, i
);
2290 *methods
= gdb::make_array_view (f
, len
);
2295 /* Resolve any stub methods. */
2296 check_stub_method_group (type
, i
);
2303 /* Unlike source methods, xmethods can be accumulated over successive
2304 recursive calls. In other words, an xmethod named 'm' in a class
2305 will not hide an xmethod named 'm' in its base class(es). We want
2306 it to be this way because xmethods are after all convenience functions
2307 and hence there is no point restricting them with something like method
2308 hiding. Moreover, if hiding is done for xmethods as well, then we will
2309 have to provide a mechanism to un-hide (like the 'using' construct). */
2310 get_matching_xmethod_workers (type
, method
, xmethods
);
2312 /* If source methods are not found in current class, look for them in the
2313 base classes. We also have to go through the base classes to gather
2314 extension methods. */
2315 for (i
= TYPE_N_BASECLASSES (type
) - 1; i
>= 0; i
--)
2317 LONGEST base_offset
;
2319 if (BASETYPE_VIA_VIRTUAL (type
, i
))
2321 base_offset
= baseclass_offset (type
, i
,
2322 value_contents_for_printing (*argp
),
2323 value_offset (*argp
) + offset
,
2324 value_address (*argp
), *argp
);
2326 else /* Non-virtual base, simply use bit position from debug
2329 base_offset
= TYPE_BASECLASS_BITPOS (type
, i
) / 8;
2332 find_method_list (argp
, method
, base_offset
+ offset
,
2333 TYPE_BASECLASS (type
, i
), methods
,
2334 xmethods
, basetype
, boffset
);
2338 /* Return the list of overloaded methods of a specified name. The methods
2339 could be those GDB finds in the binary, or xmethod. Methods found in
2340 the binary are returned in METHODS, and xmethods are returned in
2343 ARGP is a pointer to a pointer to a value (the object).
2344 METHOD is the method name.
2345 OFFSET is the offset within the value contents.
2346 METHODS is the list of matching overloaded instances defined in
2347 the source language.
2348 XMETHODS is the vector of matching xmethod workers defined in
2349 extension languages.
2350 BASETYPE is set to the type of the base subobject that defines the
2352 BOFFSET is the offset of the base subobject which defines the method. */
2355 value_find_oload_method_list (struct value
**argp
, const char *method
,
2357 gdb::array_view
<fn_field
> *methods
,
2358 std::vector
<xmethod_worker_up
> *xmethods
,
2359 struct type
**basetype
, LONGEST
*boffset
)
2363 t
= check_typedef (value_type (*argp
));
2365 /* Code snarfed from value_struct_elt. */
2366 while (t
->code () == TYPE_CODE_PTR
|| TYPE_IS_REFERENCE (t
))
2368 *argp
= value_ind (*argp
);
2369 /* Don't coerce fn pointer to fn and then back again! */
2370 if (check_typedef (value_type (*argp
))->code () != TYPE_CODE_FUNC
)
2371 *argp
= coerce_array (*argp
);
2372 t
= check_typedef (value_type (*argp
));
2375 if (t
->code () != TYPE_CODE_STRUCT
2376 && t
->code () != TYPE_CODE_UNION
)
2377 error (_("Attempt to extract a component of a "
2378 "value that is not a struct or union"));
2380 gdb_assert (methods
!= NULL
&& xmethods
!= NULL
);
2382 /* Clear the lists. */
2386 find_method_list (argp
, method
, 0, t
, methods
, xmethods
,
2390 /* Given an array of arguments (ARGS) (which includes an entry for
2391 "this" in the case of C++ methods), the NAME of a function, and
2392 whether it's a method or not (METHOD), find the best function that
2393 matches on the argument types according to the overload resolution
2396 METHOD can be one of three values:
2397 NON_METHOD for non-member functions.
2398 METHOD: for member functions.
2399 BOTH: used for overload resolution of operators where the
2400 candidates are expected to be either member or non member
2401 functions. In this case the first argument ARGTYPES
2402 (representing 'this') is expected to be a reference to the
2403 target object, and will be dereferenced when attempting the
2406 In the case of class methods, the parameter OBJ is an object value
2407 in which to search for overloaded methods.
2409 In the case of non-method functions, the parameter FSYM is a symbol
2410 corresponding to one of the overloaded functions.
2412 Return value is an integer: 0 -> good match, 10 -> debugger applied
2413 non-standard coercions, 100 -> incompatible.
2415 If a method is being searched for, VALP will hold the value.
2416 If a non-method is being searched for, SYMP will hold the symbol
2419 If a method is being searched for, and it is a static method,
2420 then STATICP will point to a non-zero value.
2422 If NO_ADL argument dependent lookup is disabled. This is used to prevent
2423 ADL overload candidates when performing overload resolution for a fully
2426 If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
2427 read while picking the best overload match (it may be all zeroes and thus
2428 not have a vtable pointer), in which case skip virtual function lookup.
2429 This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
2432 Note: This function does *not* check the value of
2433 overload_resolution. Caller must check it to see whether overload
2434 resolution is permitted. */
2437 find_overload_match (gdb::array_view
<value
*> args
,
2438 const char *name
, enum oload_search_type method
,
2439 struct value
**objp
, struct symbol
*fsym
,
2440 struct value
**valp
, struct symbol
**symp
,
2441 int *staticp
, const int no_adl
,
2442 const enum noside noside
)
2444 struct value
*obj
= (objp
? *objp
: NULL
);
2445 struct type
*obj_type
= obj
? value_type (obj
) : NULL
;
2446 /* Index of best overloaded function. */
2447 int func_oload_champ
= -1;
2448 int method_oload_champ
= -1;
2449 int src_method_oload_champ
= -1;
2450 int ext_method_oload_champ
= -1;
2452 /* The measure for the current best match. */
2453 badness_vector method_badness
;
2454 badness_vector func_badness
;
2455 badness_vector ext_method_badness
;
2456 badness_vector src_method_badness
;
2458 struct value
*temp
= obj
;
2459 /* For methods, the list of overloaded methods. */
2460 gdb::array_view
<fn_field
> methods
;
2461 /* For non-methods, the list of overloaded function symbols. */
2462 std::vector
<symbol
*> functions
;
2463 /* For xmethods, the vector of xmethod workers. */
2464 std::vector
<xmethod_worker_up
> xmethods
;
2465 struct type
*basetype
= NULL
;
2468 const char *obj_type_name
= NULL
;
2469 const char *func_name
= NULL
;
2470 gdb::unique_xmalloc_ptr
<char> temp_func
;
2471 enum oload_classification match_quality
;
2472 enum oload_classification method_match_quality
= INCOMPATIBLE
;
2473 enum oload_classification src_method_match_quality
= INCOMPATIBLE
;
2474 enum oload_classification ext_method_match_quality
= INCOMPATIBLE
;
2475 enum oload_classification func_match_quality
= INCOMPATIBLE
;
2477 /* Get the list of overloaded methods or functions. */
2478 if (method
== METHOD
|| method
== BOTH
)
2482 /* OBJ may be a pointer value rather than the object itself. */
2483 obj
= coerce_ref (obj
);
2484 while (check_typedef (value_type (obj
))->code () == TYPE_CODE_PTR
)
2485 obj
= coerce_ref (value_ind (obj
));
2486 obj_type_name
= value_type (obj
)->name ();
2488 /* First check whether this is a data member, e.g. a pointer to
2490 if (check_typedef (value_type (obj
))->code () == TYPE_CODE_STRUCT
)
2492 *valp
= search_struct_field (name
, obj
,
2493 check_typedef (value_type (obj
)), 0);
2501 /* Retrieve the list of methods with the name NAME. */
2502 value_find_oload_method_list (&temp
, name
, 0, &methods
,
2503 &xmethods
, &basetype
, &boffset
);
2504 /* If this is a method only search, and no methods were found
2505 the search has failed. */
2506 if (method
== METHOD
&& methods
.empty () && xmethods
.empty ())
2507 error (_("Couldn't find method %s%s%s"),
2509 (obj_type_name
&& *obj_type_name
) ? "::" : "",
2511 /* If we are dealing with stub method types, they should have
2512 been resolved by find_method_list via
2513 value_find_oload_method_list above. */
2514 if (!methods
.empty ())
2516 gdb_assert (TYPE_SELF_TYPE (methods
[0].type
) != NULL
);
2518 src_method_oload_champ
2519 = find_oload_champ (args
,
2521 methods
.data (), NULL
, NULL
,
2522 &src_method_badness
);
2524 src_method_match_quality
= classify_oload_match
2525 (src_method_badness
, args
.size (),
2526 oload_method_static_p (methods
.data (), src_method_oload_champ
));
2529 if (!xmethods
.empty ())
2531 ext_method_oload_champ
2532 = find_oload_champ (args
,
2534 NULL
, xmethods
.data (), NULL
,
2535 &ext_method_badness
);
2536 ext_method_match_quality
= classify_oload_match (ext_method_badness
,
2540 if (src_method_oload_champ
>= 0 && ext_method_oload_champ
>= 0)
2542 switch (compare_badness (ext_method_badness
, src_method_badness
))
2544 case 0: /* Src method and xmethod are equally good. */
2545 /* If src method and xmethod are equally good, then
2546 xmethod should be the winner. Hence, fall through to the
2547 case where a xmethod is better than the source
2548 method, except when the xmethod match quality is
2551 case 1: /* Src method and ext method are incompatible. */
2552 /* If ext method match is not standard, then let source method
2553 win. Otherwise, fallthrough to let xmethod win. */
2554 if (ext_method_match_quality
!= STANDARD
)
2556 method_oload_champ
= src_method_oload_champ
;
2557 method_badness
= src_method_badness
;
2558 ext_method_oload_champ
= -1;
2559 method_match_quality
= src_method_match_quality
;
2563 case 2: /* Ext method is champion. */
2564 method_oload_champ
= ext_method_oload_champ
;
2565 method_badness
= ext_method_badness
;
2566 src_method_oload_champ
= -1;
2567 method_match_quality
= ext_method_match_quality
;
2569 case 3: /* Src method is champion. */
2570 method_oload_champ
= src_method_oload_champ
;
2571 method_badness
= src_method_badness
;
2572 ext_method_oload_champ
= -1;
2573 method_match_quality
= src_method_match_quality
;
2576 gdb_assert_not_reached ("Unexpected overload comparison "
2581 else if (src_method_oload_champ
>= 0)
2583 method_oload_champ
= src_method_oload_champ
;
2584 method_badness
= src_method_badness
;
2585 method_match_quality
= src_method_match_quality
;
2587 else if (ext_method_oload_champ
>= 0)
2589 method_oload_champ
= ext_method_oload_champ
;
2590 method_badness
= ext_method_badness
;
2591 method_match_quality
= ext_method_match_quality
;
2595 if (method
== NON_METHOD
|| method
== BOTH
)
2597 const char *qualified_name
= NULL
;
2599 /* If the overload match is being search for both as a method
2600 and non member function, the first argument must now be
2603 args
[0] = value_ind (args
[0]);
2607 qualified_name
= fsym
->natural_name ();
2609 /* If we have a function with a C++ name, try to extract just
2610 the function part. Do not try this for non-functions (e.g.
2611 function pointers). */
2613 && (check_typedef (SYMBOL_TYPE (fsym
))->code ()
2616 temp_func
= cp_func_name (qualified_name
);
2618 /* If cp_func_name did not remove anything, the name of the
2619 symbol did not include scope or argument types - it was
2620 probably a C-style function. */
2621 if (temp_func
!= nullptr)
2623 if (strcmp (temp_func
.get (), qualified_name
) == 0)
2626 func_name
= temp_func
.get ();
2633 qualified_name
= name
;
2636 /* If there was no C++ name, this must be a C-style function or
2637 not a function at all. Just return the same symbol. Do the
2638 same if cp_func_name fails for some reason. */
2639 if (func_name
== NULL
)
2645 func_oload_champ
= find_oload_champ_namespace (args
,
2652 if (func_oload_champ
>= 0)
2653 func_match_quality
= classify_oload_match (func_badness
,
2657 /* Did we find a match ? */
2658 if (method_oload_champ
== -1 && func_oload_champ
== -1)
2659 throw_error (NOT_FOUND_ERROR
,
2660 _("No symbol \"%s\" in current context."),
2663 /* If we have found both a method match and a function
2664 match, find out which one is better, and calculate match
2666 if (method_oload_champ
>= 0 && func_oload_champ
>= 0)
2668 switch (compare_badness (func_badness
, method_badness
))
2670 case 0: /* Top two contenders are equally good. */
2671 /* FIXME: GDB does not support the general ambiguous case.
2672 All candidates should be collected and presented the
2674 error (_("Ambiguous overload resolution"));
2676 case 1: /* Incomparable top contenders. */
2677 /* This is an error incompatible candidates
2678 should not have been proposed. */
2679 error (_("Internal error: incompatible "
2680 "overload candidates proposed"));
2682 case 2: /* Function champion. */
2683 method_oload_champ
= -1;
2684 match_quality
= func_match_quality
;
2686 case 3: /* Method champion. */
2687 func_oload_champ
= -1;
2688 match_quality
= method_match_quality
;
2691 error (_("Internal error: unexpected overload comparison result"));
2697 /* We have either a method match or a function match. */
2698 if (method_oload_champ
>= 0)
2699 match_quality
= method_match_quality
;
2701 match_quality
= func_match_quality
;
2704 if (match_quality
== INCOMPATIBLE
)
2706 if (method
== METHOD
)
2707 error (_("Cannot resolve method %s%s%s to any overloaded instance"),
2709 (obj_type_name
&& *obj_type_name
) ? "::" : "",
2712 error (_("Cannot resolve function %s to any overloaded instance"),
2715 else if (match_quality
== NON_STANDARD
)
2717 if (method
== METHOD
)
2718 warning (_("Using non-standard conversion to match "
2719 "method %s%s%s to supplied arguments"),
2721 (obj_type_name
&& *obj_type_name
) ? "::" : "",
2724 warning (_("Using non-standard conversion to match "
2725 "function %s to supplied arguments"),
2729 if (staticp
!= NULL
)
2730 *staticp
= oload_method_static_p (methods
.data (), method_oload_champ
);
2732 if (method_oload_champ
>= 0)
2734 if (src_method_oload_champ
>= 0)
2736 if (TYPE_FN_FIELD_VIRTUAL_P (methods
, method_oload_champ
)
2737 && noside
!= EVAL_AVOID_SIDE_EFFECTS
)
2739 *valp
= value_virtual_fn_field (&temp
, methods
.data (),
2740 method_oload_champ
, basetype
,
2744 *valp
= value_fn_field (&temp
, methods
.data (),
2745 method_oload_champ
, basetype
, boffset
);
2748 *valp
= value_from_xmethod
2749 (std::move (xmethods
[ext_method_oload_champ
]));
2752 *symp
= functions
[func_oload_champ
];
2756 struct type
*temp_type
= check_typedef (value_type (temp
));
2757 struct type
*objtype
= check_typedef (obj_type
);
2759 if (temp_type
->code () != TYPE_CODE_PTR
2760 && (objtype
->code () == TYPE_CODE_PTR
2761 || TYPE_IS_REFERENCE (objtype
)))
2763 temp
= value_addr (temp
);
2768 switch (match_quality
)
2774 default: /* STANDARD */
2779 /* Find the best overload match, searching for FUNC_NAME in namespaces
2780 contained in QUALIFIED_NAME until it either finds a good match or
2781 runs out of namespaces. It stores the overloaded functions in
2782 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. If NO_ADL,
2783 argument dependent lookup is not performed. */
2786 find_oload_champ_namespace (gdb::array_view
<value
*> args
,
2787 const char *func_name
,
2788 const char *qualified_name
,
2789 std::vector
<symbol
*> *oload_syms
,
2790 badness_vector
*oload_champ_bv
,
2795 find_oload_champ_namespace_loop (args
,
2798 oload_syms
, oload_champ_bv
,
2805 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
2806 how deep we've looked for namespaces, and the champ is stored in
2807 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
2808 if it isn't. Other arguments are the same as in
2809 find_oload_champ_namespace. */
2812 find_oload_champ_namespace_loop (gdb::array_view
<value
*> args
,
2813 const char *func_name
,
2814 const char *qualified_name
,
2816 std::vector
<symbol
*> *oload_syms
,
2817 badness_vector
*oload_champ_bv
,
2821 int next_namespace_len
= namespace_len
;
2822 int searched_deeper
= 0;
2823 int new_oload_champ
;
2824 char *new_namespace
;
2826 if (next_namespace_len
!= 0)
2828 gdb_assert (qualified_name
[next_namespace_len
] == ':');
2829 next_namespace_len
+= 2;
2831 next_namespace_len
+=
2832 cp_find_first_component (qualified_name
+ next_namespace_len
);
2834 /* First, see if we have a deeper namespace we can search in.
2835 If we get a good match there, use it. */
2837 if (qualified_name
[next_namespace_len
] == ':')
2839 searched_deeper
= 1;
2841 if (find_oload_champ_namespace_loop (args
,
2842 func_name
, qualified_name
,
2844 oload_syms
, oload_champ_bv
,
2845 oload_champ
, no_adl
))
2851 /* If we reach here, either we're in the deepest namespace or we
2852 didn't find a good match in a deeper namespace. But, in the
2853 latter case, we still have a bad match in a deeper namespace;
2854 note that we might not find any match at all in the current
2855 namespace. (There's always a match in the deepest namespace,
2856 because this overload mechanism only gets called if there's a
2857 function symbol to start off with.) */
2859 new_namespace
= (char *) alloca (namespace_len
+ 1);
2860 strncpy (new_namespace
, qualified_name
, namespace_len
);
2861 new_namespace
[namespace_len
] = '\0';
2863 std::vector
<symbol
*> new_oload_syms
2864 = make_symbol_overload_list (func_name
, new_namespace
);
2866 /* If we have reached the deepest level perform argument
2867 determined lookup. */
2868 if (!searched_deeper
&& !no_adl
)
2871 struct type
**arg_types
;
2873 /* Prepare list of argument types for overload resolution. */
2874 arg_types
= (struct type
**)
2875 alloca (args
.size () * (sizeof (struct type
*)));
2876 for (ix
= 0; ix
< args
.size (); ix
++)
2877 arg_types
[ix
] = value_type (args
[ix
]);
2878 add_symbol_overload_list_adl ({arg_types
, args
.size ()}, func_name
,
2882 badness_vector new_oload_champ_bv
;
2883 new_oload_champ
= find_oload_champ (args
,
2884 new_oload_syms
.size (),
2885 NULL
, NULL
, new_oload_syms
.data (),
2886 &new_oload_champ_bv
);
2888 /* Case 1: We found a good match. Free earlier matches (if any),
2889 and return it. Case 2: We didn't find a good match, but we're
2890 not the deepest function. Then go with the bad match that the
2891 deeper function found. Case 3: We found a bad match, and we're
2892 the deepest function. Then return what we found, even though
2893 it's a bad match. */
2895 if (new_oload_champ
!= -1
2896 && classify_oload_match (new_oload_champ_bv
, args
.size (), 0) == STANDARD
)
2898 *oload_syms
= std::move (new_oload_syms
);
2899 *oload_champ
= new_oload_champ
;
2900 *oload_champ_bv
= std::move (new_oload_champ_bv
);
2903 else if (searched_deeper
)
2909 *oload_syms
= std::move (new_oload_syms
);
2910 *oload_champ
= new_oload_champ
;
2911 *oload_champ_bv
= std::move (new_oload_champ_bv
);
2916 /* Look for a function to take ARGS. Find the best match from among
2917 the overloaded methods or functions given by METHODS or FUNCTIONS
2918 or XMETHODS, respectively. One, and only one of METHODS, FUNCTIONS
2919 and XMETHODS can be non-NULL.
2921 NUM_FNS is the length of the array pointed at by METHODS, FUNCTIONS
2922 or XMETHODS, whichever is non-NULL.
2924 Return the index of the best match; store an indication of the
2925 quality of the match in OLOAD_CHAMP_BV. */
2928 find_oload_champ (gdb::array_view
<value
*> args
,
2931 xmethod_worker_up
*xmethods
,
2933 badness_vector
*oload_champ_bv
)
2935 /* A measure of how good an overloaded instance is. */
2937 /* Index of best overloaded function. */
2938 int oload_champ
= -1;
2939 /* Current ambiguity state for overload resolution. */
2940 int oload_ambiguous
= 0;
2941 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
2943 /* A champion can be found among methods alone, or among functions
2944 alone, or in xmethods alone, but not in more than one of these
2946 gdb_assert ((methods
!= NULL
) + (functions
!= NULL
) + (xmethods
!= NULL
)
2949 /* Consider each candidate in turn. */
2950 for (size_t ix
= 0; ix
< num_fns
; ix
++)
2953 int static_offset
= 0;
2954 std::vector
<type
*> parm_types
;
2956 if (xmethods
!= NULL
)
2957 parm_types
= xmethods
[ix
]->get_arg_types ();
2962 if (methods
!= NULL
)
2964 nparms
= TYPE_FN_FIELD_TYPE (methods
, ix
)->num_fields ();
2965 static_offset
= oload_method_static_p (methods
, ix
);
2968 nparms
= SYMBOL_TYPE (functions
[ix
])->num_fields ();
2970 parm_types
.reserve (nparms
);
2971 for (jj
= 0; jj
< nparms
; jj
++)
2973 type
*t
= (methods
!= NULL
2974 ? (TYPE_FN_FIELD_ARGS (methods
, ix
)[jj
].type ())
2975 : SYMBOL_TYPE (functions
[ix
])->field (jj
).type ());
2976 parm_types
.push_back (t
);
2980 /* Compare parameter types to supplied argument types. Skip
2981 THIS for static methods. */
2982 bv
= rank_function (parm_types
,
2983 args
.slice (static_offset
));
2987 if (methods
!= NULL
)
2988 fprintf_filtered (gdb_stderr
,
2989 "Overloaded method instance %s, # of parms %d\n",
2990 methods
[ix
].physname
, (int) parm_types
.size ());
2991 else if (xmethods
!= NULL
)
2992 fprintf_filtered (gdb_stderr
,
2993 "Xmethod worker, # of parms %d\n",
2994 (int) parm_types
.size ());
2996 fprintf_filtered (gdb_stderr
,
2997 "Overloaded function instance "
2998 "%s # of parms %d\n",
2999 functions
[ix
]->demangled_name (),
3000 (int) parm_types
.size ());
3002 fprintf_filtered (gdb_stderr
,
3003 "...Badness of length : {%d, %d}\n",
3004 bv
[0].rank
, bv
[0].subrank
);
3006 for (jj
= 1; jj
< bv
.size (); jj
++)
3007 fprintf_filtered (gdb_stderr
,
3008 "...Badness of arg %d : {%d, %d}\n",
3009 jj
, bv
[jj
].rank
, bv
[jj
].subrank
);
3012 if (oload_champ_bv
->empty ())
3014 *oload_champ_bv
= std::move (bv
);
3017 else /* See whether current candidate is better or worse than
3019 switch (compare_badness (bv
, *oload_champ_bv
))
3021 case 0: /* Top two contenders are equally good. */
3022 oload_ambiguous
= 1;
3024 case 1: /* Incomparable top contenders. */
3025 oload_ambiguous
= 2;
3027 case 2: /* New champion, record details. */
3028 *oload_champ_bv
= std::move (bv
);
3029 oload_ambiguous
= 0;
3037 fprintf_filtered (gdb_stderr
, "Overload resolution "
3038 "champion is %d, ambiguous? %d\n",
3039 oload_champ
, oload_ambiguous
);
3045 /* Return 1 if we're looking at a static method, 0 if we're looking at
3046 a non-static method or a function that isn't a method. */
3049 oload_method_static_p (struct fn_field
*fns_ptr
, int index
)
3051 if (fns_ptr
&& index
>= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr
, index
))
3057 /* Check how good an overload match OLOAD_CHAMP_BV represents. */
3059 static enum oload_classification
3060 classify_oload_match (const badness_vector
&oload_champ_bv
,
3065 enum oload_classification worst
= STANDARD
;
3067 for (ix
= 1; ix
<= nargs
- static_offset
; ix
++)
3069 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
3070 or worse return INCOMPATIBLE. */
3071 if (compare_ranks (oload_champ_bv
[ix
],
3072 INCOMPATIBLE_TYPE_BADNESS
) <= 0)
3073 return INCOMPATIBLE
; /* Truly mismatched types. */
3074 /* Otherwise If this conversion is as bad as
3075 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
3076 else if (compare_ranks (oload_champ_bv
[ix
],
3077 NS_POINTER_CONVERSION_BADNESS
) <= 0)
3078 worst
= NON_STANDARD
; /* Non-standard type conversions
3082 /* If no INCOMPATIBLE classification was found, return the worst one
3083 that was found (if any). */
3087 /* C++: return 1 is NAME is a legitimate name for the destructor of
3088 type TYPE. If TYPE does not have a destructor, or if NAME is
3089 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
3090 have CHECK_TYPEDEF applied, this function will apply it itself. */
3093 destructor_name_p (const char *name
, struct type
*type
)
3097 const char *dname
= type_name_or_error (type
);
3098 const char *cp
= strchr (dname
, '<');
3101 /* Do not compare the template part for template classes. */
3103 len
= strlen (dname
);
3106 if (strlen (name
+ 1) != len
|| strncmp (dname
, name
+ 1, len
) != 0)
3107 error (_("name of destructor must equal name of class"));
3114 /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
3115 class". If the name is found, return a value representing it;
3116 otherwise throw an exception. */
3118 static struct value
*
3119 enum_constant_from_type (struct type
*type
, const char *name
)
3122 int name_len
= strlen (name
);
3124 gdb_assert (type
->code () == TYPE_CODE_ENUM
3125 && TYPE_DECLARED_CLASS (type
));
3127 for (i
= TYPE_N_BASECLASSES (type
); i
< type
->num_fields (); ++i
)
3129 const char *fname
= TYPE_FIELD_NAME (type
, i
);
3132 if (TYPE_FIELD_LOC_KIND (type
, i
) != FIELD_LOC_KIND_ENUMVAL
3136 /* Look for the trailing "::NAME", since enum class constant
3137 names are qualified here. */
3138 len
= strlen (fname
);
3139 if (len
+ 2 >= name_len
3140 && fname
[len
- name_len
- 2] == ':'
3141 && fname
[len
- name_len
- 1] == ':'
3142 && strcmp (&fname
[len
- name_len
], name
) == 0)
3143 return value_from_longest (type
, TYPE_FIELD_ENUMVAL (type
, i
));
3146 error (_("no constant named \"%s\" in enum \"%s\""),
3147 name
, type
->name ());
3150 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3151 return the appropriate member (or the address of the member, if
3152 WANT_ADDRESS). This function is used to resolve user expressions
3153 of the form "DOMAIN::NAME". For more details on what happens, see
3154 the comment before value_struct_elt_for_reference. */
3157 value_aggregate_elt (struct type
*curtype
, const char *name
,
3158 struct type
*expect_type
, int want_address
,
3161 switch (curtype
->code ())
3163 case TYPE_CODE_STRUCT
:
3164 case TYPE_CODE_UNION
:
3165 return value_struct_elt_for_reference (curtype
, 0, curtype
,
3167 want_address
, noside
);
3168 case TYPE_CODE_NAMESPACE
:
3169 return value_namespace_elt (curtype
, name
,
3170 want_address
, noside
);
3172 case TYPE_CODE_ENUM
:
3173 return enum_constant_from_type (curtype
, name
);
3176 internal_error (__FILE__
, __LINE__
,
3177 _("non-aggregate type in value_aggregate_elt"));
3181 /* Compares the two method/function types T1 and T2 for "equality"
3182 with respect to the methods' parameters. If the types of the
3183 two parameter lists are the same, returns 1; 0 otherwise. This
3184 comparison may ignore any artificial parameters in T1 if
3185 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
3186 the first artificial parameter in T1, assumed to be a 'this' pointer.
3188 The type T2 is expected to have come from make_params (in eval.c). */
3191 compare_parameters (struct type
*t1
, struct type
*t2
, int skip_artificial
)
3195 if (t1
->num_fields () > 0 && TYPE_FIELD_ARTIFICIAL (t1
, 0))
3198 /* If skipping artificial fields, find the first real field
3200 if (skip_artificial
)
3202 while (start
< t1
->num_fields ()
3203 && TYPE_FIELD_ARTIFICIAL (t1
, start
))
3207 /* Now compare parameters. */
3209 /* Special case: a method taking void. T1 will contain no
3210 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
3211 if ((t1
->num_fields () - start
) == 0 && t2
->num_fields () == 1
3212 && t2
->field (0).type ()->code () == TYPE_CODE_VOID
)
3215 if ((t1
->num_fields () - start
) == t2
->num_fields ())
3219 for (i
= 0; i
< t2
->num_fields (); ++i
)
3221 if (compare_ranks (rank_one_type (t1
->field (start
+ i
).type (),
3222 t2
->field (i
).type (), NULL
),
3223 EXACT_MATCH_BADNESS
) != 0)
3233 /* C++: Given an aggregate type VT, and a class type CLS, search
3234 recursively for CLS using value V; If found, store the offset
3235 which is either fetched from the virtual base pointer if CLS
3236 is virtual or accumulated offset of its parent classes if
3237 CLS is non-virtual in *BOFFS, set ISVIRT to indicate if CLS
3238 is virtual, and return true. If not found, return false. */
3241 get_baseclass_offset (struct type
*vt
, struct type
*cls
,
3242 struct value
*v
, int *boffs
, bool *isvirt
)
3244 for (int i
= 0; i
< TYPE_N_BASECLASSES (vt
); i
++)
3246 struct type
*t
= vt
->field (i
).type ();
3247 if (types_equal (t
, cls
))
3249 if (BASETYPE_VIA_VIRTUAL (vt
, i
))
3251 const gdb_byte
*adr
= value_contents_for_printing (v
);
3252 *boffs
= baseclass_offset (vt
, i
, adr
, value_offset (v
),
3253 value_as_long (v
), v
);
3261 if (get_baseclass_offset (check_typedef (t
), cls
, v
, boffs
, isvirt
))
3263 if (*isvirt
== false) /* Add non-virtual base offset. */
3265 const gdb_byte
*adr
= value_contents_for_printing (v
);
3266 *boffs
+= baseclass_offset (vt
, i
, adr
, value_offset (v
),
3267 value_as_long (v
), v
);
3276 /* C++: Given an aggregate type CURTYPE, and a member name NAME,
3277 return the address of this member as a "pointer to member" type.
3278 If INTYPE is non-null, then it will be the type of the member we
3279 are looking for. This will help us resolve "pointers to member
3280 functions". This function is used to resolve user expressions of
3281 the form "DOMAIN::NAME". */
3283 static struct value
*
3284 value_struct_elt_for_reference (struct type
*domain
, int offset
,
3285 struct type
*curtype
, const char *name
,
3286 struct type
*intype
,
3290 struct type
*t
= check_typedef (curtype
);
3292 struct value
*result
;
3294 if (t
->code () != TYPE_CODE_STRUCT
3295 && t
->code () != TYPE_CODE_UNION
)
3296 error (_("Internal error: non-aggregate type "
3297 "to value_struct_elt_for_reference"));
3299 for (i
= t
->num_fields () - 1; i
>= TYPE_N_BASECLASSES (t
); i
--)
3301 const char *t_field_name
= TYPE_FIELD_NAME (t
, i
);
3303 if (t_field_name
&& strcmp (t_field_name
, name
) == 0)
3305 if (field_is_static (&t
->field (i
)))
3307 struct value
*v
= value_static_field (t
, i
);
3312 if (TYPE_FIELD_PACKED (t
, i
))
3313 error (_("pointers to bitfield members not allowed"));
3316 return value_from_longest
3317 (lookup_memberptr_type (t
->field (i
).type (), domain
),
3318 offset
+ (LONGEST
) (TYPE_FIELD_BITPOS (t
, i
) >> 3));
3319 else if (noside
!= EVAL_NORMAL
)
3320 return allocate_value (t
->field (i
).type ());
3323 /* Try to evaluate NAME as a qualified name with implicit
3324 this pointer. In this case, attempt to return the
3325 equivalent to `this->*(&TYPE::NAME)'. */
3326 struct value
*v
= value_of_this_silent (current_language
);
3329 struct value
*ptr
, *this_v
= v
;
3331 struct type
*type
, *tmp
;
3333 ptr
= value_aggregate_elt (domain
, name
, NULL
, 1, noside
);
3334 type
= check_typedef (value_type (ptr
));
3335 gdb_assert (type
!= NULL
3336 && type
->code () == TYPE_CODE_MEMBERPTR
);
3337 tmp
= lookup_pointer_type (TYPE_SELF_TYPE (type
));
3338 v
= value_cast_pointers (tmp
, v
, 1);
3339 mem_offset
= value_as_long (ptr
);
3340 if (domain
!= curtype
)
3342 /* Find class offset of type CURTYPE from either its
3343 parent type DOMAIN or the type of implied this. */
3345 bool isvirt
= false;
3346 if (get_baseclass_offset (domain
, curtype
, v
, &boff
,
3351 struct type
*p
= check_typedef (value_type (this_v
));
3352 p
= check_typedef (TYPE_TARGET_TYPE (p
));
3353 if (get_baseclass_offset (p
, curtype
, this_v
,
3358 tmp
= lookup_pointer_type (TYPE_TARGET_TYPE (type
));
3359 result
= value_from_pointer (tmp
,
3360 value_as_long (v
) + mem_offset
);
3361 return value_ind (result
);
3364 error (_("Cannot reference non-static field \"%s\""), name
);
3369 /* C++: If it was not found as a data field, then try to return it
3370 as a pointer to a method. */
3372 /* Perform all necessary dereferencing. */
3373 while (intype
&& intype
->code () == TYPE_CODE_PTR
)
3374 intype
= TYPE_TARGET_TYPE (intype
);
3376 for (i
= TYPE_NFN_FIELDS (t
) - 1; i
>= 0; --i
)
3378 const char *t_field_name
= TYPE_FN_FIELDLIST_NAME (t
, i
);
3380 if (t_field_name
&& strcmp (t_field_name
, name
) == 0)
3383 int len
= TYPE_FN_FIELDLIST_LENGTH (t
, i
);
3384 struct fn_field
*f
= TYPE_FN_FIELDLIST1 (t
, i
);
3386 check_stub_method_group (t
, i
);
3390 for (j
= 0; j
< len
; ++j
)
3392 if (TYPE_CONST (intype
) != TYPE_FN_FIELD_CONST (f
, j
))
3394 if (TYPE_VOLATILE (intype
) != TYPE_FN_FIELD_VOLATILE (f
, 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 struct value
*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
, curtype
->name ());
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
= curtype
->name ();
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 LONGEST
*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_IS_REFERENCE (type
))
3586 target
= coerce_ref (v
);
3587 else if (type
->code () == TYPE_CODE_PTR
)
3592 target
= value_ind (v
);
3594 catch (const gdb_exception_error
&except
)
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
3609 real_type
= value_rtti_type (target
, full
, top
, using_enc
);
3613 /* Copy qualifiers to the referenced object. */
3614 target_type
= value_type (target
);
3615 real_type
= make_cv_type (TYPE_CONST (target_type
),
3616 TYPE_VOLATILE (target_type
), real_type
, NULL
);
3617 if (TYPE_IS_REFERENCE (type
))
3618 real_type
= lookup_reference_type (real_type
, type
->code ());
3619 else if (type
->code () == TYPE_CODE_PTR
)
3620 real_type
= lookup_pointer_type (real_type
);
3622 internal_error (__FILE__
, __LINE__
, _("Unexpected value type."));
3624 /* Copy qualifiers to the pointer/reference. */
3625 real_type
= make_cv_type (TYPE_CONST (type
), TYPE_VOLATILE (type
),
3632 /* Given a value pointed to by ARGP, check its real run-time type, and
3633 if that is different from the enclosing type, create a new value
3634 using the real run-time type as the enclosing type (and of the same
3635 type as ARGP) and return it, with the embedded offset adjusted to
3636 be the correct offset to the enclosed object. RTYPE is the type,
3637 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
3638 by value_rtti_type(). If these are available, they can be supplied
3639 and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
3640 NULL if they're not available. */
3643 value_full_object (struct value
*argp
,
3645 int xfull
, int xtop
,
3648 struct type
*real_type
;
3652 struct value
*new_val
;
3659 using_enc
= xusing_enc
;
3662 real_type
= value_rtti_type (argp
, &full
, &top
, &using_enc
);
3664 /* If no RTTI data, or if object is already complete, do nothing. */
3665 if (!real_type
|| real_type
== value_enclosing_type (argp
))
3668 /* In a destructor we might see a real type that is a superclass of
3669 the object's type. In this case it is better to leave the object
3672 && TYPE_LENGTH (real_type
) < TYPE_LENGTH (value_enclosing_type (argp
)))
3675 /* If we have the full object, but for some reason the enclosing
3676 type is wrong, set it. */
3677 /* pai: FIXME -- sounds iffy */
3680 argp
= value_copy (argp
);
3681 set_value_enclosing_type (argp
, real_type
);
3685 /* Check if object is in memory. */
3686 if (VALUE_LVAL (argp
) != lval_memory
)
3688 warning (_("Couldn't retrieve complete object of RTTI "
3689 "type %s; object may be in register(s)."),
3690 real_type
->name ());
3695 /* All other cases -- retrieve the complete object. */
3696 /* Go back by the computed top_offset from the beginning of the
3697 object, adjusting for the embedded offset of argp if that's what
3698 value_rtti_type used for its computation. */
3699 new_val
= value_at_lazy (real_type
, value_address (argp
) - top
+
3700 (using_enc
? 0 : value_embedded_offset (argp
)));
3701 deprecated_set_value_type (new_val
, value_type (argp
));
3702 set_value_embedded_offset (new_val
, (using_enc
3703 ? top
+ value_embedded_offset (argp
)
3709 /* Return the value of the local variable, if one exists. Throw error
3710 otherwise, such as if the request is made in an inappropriate context. */
3713 value_of_this (const struct language_defn
*lang
)
3715 struct block_symbol sym
;
3716 const struct block
*b
;
3717 struct frame_info
*frame
;
3719 if (lang
->name_of_this () == NULL
)
3720 error (_("no `this' in current language"));
3722 frame
= get_selected_frame (_("no frame selected"));
3724 b
= get_frame_block (frame
, NULL
);
3726 sym
= lookup_language_this (lang
, b
);
3727 if (sym
.symbol
== NULL
)
3728 error (_("current stack frame does not contain a variable named `%s'"),
3729 lang
->name_of_this ());
3731 return read_var_value (sym
.symbol
, sym
.block
, frame
);
3734 /* Return the value of the local variable, if one exists. Return NULL
3735 otherwise. Never throw error. */
3738 value_of_this_silent (const struct language_defn
*lang
)
3740 struct value
*ret
= NULL
;
3744 ret
= value_of_this (lang
);
3746 catch (const gdb_exception_error
&except
)
3753 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
3754 elements long, starting at LOWBOUND. The result has the same lower
3755 bound as the original ARRAY. */
3758 value_slice (struct value
*array
, int lowbound
, int length
)
3760 struct type
*slice_range_type
, *slice_type
, *range_type
;
3761 LONGEST lowerbound
, upperbound
;
3762 struct value
*slice
;
3763 struct type
*array_type
;
3765 array_type
= check_typedef (value_type (array
));
3766 if (array_type
->code () != TYPE_CODE_ARRAY
3767 && array_type
->code () != TYPE_CODE_STRING
)
3768 error (_("cannot take slice of non-array"));
3770 if (type_not_allocated (array_type
))
3771 error (_("array not allocated"));
3772 if (type_not_associated (array_type
))
3773 error (_("array not associated"));
3775 range_type
= array_type
->index_type ();
3776 if (get_discrete_bounds (range_type
, &lowerbound
, &upperbound
) < 0)
3777 error (_("slice from bad array or bitstring"));
3779 if (lowbound
< lowerbound
|| length
< 0
3780 || lowbound
+ length
- 1 > upperbound
)
3781 error (_("slice out of range"));
3783 /* FIXME-type-allocation: need a way to free this type when we are
3785 slice_range_type
= create_static_range_type (NULL
,
3786 TYPE_TARGET_TYPE (range_type
),
3788 lowbound
+ length
- 1);
3791 struct type
*element_type
= TYPE_TARGET_TYPE (array_type
);
3793 = (lowbound
- lowerbound
) * TYPE_LENGTH (check_typedef (element_type
));
3795 slice_type
= create_array_type (NULL
,
3798 slice_type
->set_code (array_type
->code ());
3800 if (VALUE_LVAL (array
) == lval_memory
&& value_lazy (array
))
3801 slice
= allocate_value_lazy (slice_type
);
3804 slice
= allocate_value (slice_type
);
3805 value_contents_copy (slice
, 0, array
, offset
,
3806 type_length_units (slice_type
));
3809 set_value_component_location (slice
, array
);
3810 set_value_offset (slice
, value_offset (array
) + offset
);
3819 value_literal_complex (struct value
*arg1
,
3824 struct type
*real_type
= TYPE_TARGET_TYPE (type
);
3826 val
= allocate_value (type
);
3827 arg1
= value_cast (real_type
, arg1
);
3828 arg2
= value_cast (real_type
, arg2
);
3830 memcpy (value_contents_raw (val
),
3831 value_contents (arg1
), TYPE_LENGTH (real_type
));
3832 memcpy (value_contents_raw (val
) + TYPE_LENGTH (real_type
),
3833 value_contents (arg2
), TYPE_LENGTH (real_type
));
3840 value_real_part (struct value
*value
)
3842 struct type
*type
= check_typedef (value_type (value
));
3843 struct type
*ttype
= TYPE_TARGET_TYPE (type
);
3845 gdb_assert (type
->code () == TYPE_CODE_COMPLEX
);
3846 return value_from_component (value
, ttype
, 0);
3852 value_imaginary_part (struct value
*value
)
3854 struct type
*type
= check_typedef (value_type (value
));
3855 struct type
*ttype
= TYPE_TARGET_TYPE (type
);
3857 gdb_assert (type
->code () == TYPE_CODE_COMPLEX
);
3858 return value_from_component (value
, ttype
,
3859 TYPE_LENGTH (check_typedef (ttype
)));
3862 /* Cast a value into the appropriate complex data type. */
3864 static struct value
*
3865 cast_into_complex (struct type
*type
, struct value
*val
)
3867 struct type
*real_type
= TYPE_TARGET_TYPE (type
);
3869 if (value_type (val
)->code () == TYPE_CODE_COMPLEX
)
3871 struct type
*val_real_type
= TYPE_TARGET_TYPE (value_type (val
));
3872 struct value
*re_val
= allocate_value (val_real_type
);
3873 struct value
*im_val
= allocate_value (val_real_type
);
3875 memcpy (value_contents_raw (re_val
),
3876 value_contents (val
), TYPE_LENGTH (val_real_type
));
3877 memcpy (value_contents_raw (im_val
),
3878 value_contents (val
) + TYPE_LENGTH (val_real_type
),
3879 TYPE_LENGTH (val_real_type
));
3881 return value_literal_complex (re_val
, im_val
, type
);
3883 else if (value_type (val
)->code () == TYPE_CODE_FLT
3884 || value_type (val
)->code () == TYPE_CODE_INT
)
3885 return value_literal_complex (val
,
3886 value_zero (real_type
, not_lval
),
3889 error (_("cannot cast non-number to complex"));
3892 void _initialize_valops ();
3894 _initialize_valops ()
3896 add_setshow_boolean_cmd ("overload-resolution", class_support
,
3897 &overload_resolution
, _("\
3898 Set overload resolution in evaluating C++ functions."), _("\
3899 Show overload resolution in evaluating C++ functions."),
3901 show_overload_resolution
,
3902 &setlist
, &showlist
);
3903 overload_resolution
= 1;