1 /* Parse expressions for GDB.
3 Copyright (C) 1986-2013 Free Software Foundation, Inc.
5 Modified from expread.y by the Department of Computer Science at the
6 State University of New York at Buffalo, 1991.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 /* Parse an expression from text in a string,
24 and return the result as a struct expression pointer.
25 That structure contains arithmetic operations in reverse polish,
26 with constants represented by operations that are followed by special data.
27 See expression.h for the details of the format.
28 What is important here is that it can be built up sequentially
29 during the process of parsing; the lower levels of the tree always
30 come first in the result. */
34 #include "arch-utils.h"
35 #include "gdb_string.h"
39 #include "expression.h"
44 #include "parser-defs.h"
46 #include "symfile.h" /* for overlay functions */
49 #include "gdb_assert.h"
53 #include "exceptions.h"
54 #include "user-regs.h"
56 /* Standard set of definitions for printing, dumping, prefixifying,
57 * and evaluating expressions. */
59 const struct exp_descriptor exp_descriptor_standard
=
61 print_subexp_standard
,
62 operator_length_standard
,
63 operator_check_standard
,
65 dump_subexp_body_standard
,
66 evaluate_subexp_standard
69 /* Global variables declared in parser-defs.h (and commented there). */
70 struct expression
*expout
;
73 const struct block
*expression_context_block
;
74 CORE_ADDR expression_context_pc
;
75 const struct block
*innermost_block
;
77 static struct type_stack type_stack
;
83 /* True if parsing an expression to attempt completion. */
86 /* The index of the last struct expression directly before a '.' or
87 '->'. This is set when parsing and is only used when completing a
88 field name. It is -1 if no dereference operation was found. */
89 static int expout_last_struct
= -1;
91 /* If we are completing a tagged type name, this will be nonzero. */
92 static enum type_code expout_tag_completion_type
= TYPE_CODE_UNDEF
;
94 /* The token for tagged type name completion. */
95 static char *expout_completion_name
;
98 static unsigned int expressiondebug
= 0;
100 show_expressiondebug (struct ui_file
*file
, int from_tty
,
101 struct cmd_list_element
*c
, const char *value
)
103 fprintf_filtered (file
, _("Expression debugging is %s.\n"), value
);
107 /* Non-zero if an expression parser should set yydebug. */
111 show_parserdebug (struct ui_file
*file
, int from_tty
,
112 struct cmd_list_element
*c
, const char *value
)
114 fprintf_filtered (file
, _("Parser debugging is %s.\n"), value
);
118 static void free_funcalls (void *ignore
);
120 static int prefixify_subexp (struct expression
*, struct expression
*, int,
123 static struct expression
*parse_exp_in_context (char **, CORE_ADDR
,
124 const struct block
*, int,
127 void _initialize_parse (void);
129 /* Data structure for saving values of arglist_len for function calls whose
130 arguments contain other function calls. */
134 struct funcall
*next
;
138 static struct funcall
*funcall_chain
;
140 /* Begin counting arguments for a function call,
141 saving the data about any containing call. */
148 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
149 new->next
= funcall_chain
;
150 new->arglist_len
= arglist_len
;
155 /* Return the number of arguments in a function call just terminated,
156 and restore the data for the containing function call. */
161 int val
= arglist_len
;
162 struct funcall
*call
= funcall_chain
;
164 funcall_chain
= call
->next
;
165 arglist_len
= call
->arglist_len
;
170 /* Free everything in the funcall chain.
171 Used when there is an error inside parsing. */
174 free_funcalls (void *ignore
)
176 struct funcall
*call
, *next
;
178 for (call
= funcall_chain
; call
; call
= next
)
185 /* This page contains the functions for adding data to the struct expression
186 being constructed. */
188 /* See definition in parser-defs.h. */
191 initialize_expout (int initial_size
, const struct language_defn
*lang
,
192 struct gdbarch
*gdbarch
)
194 expout_size
= initial_size
;
196 expout
= xmalloc (sizeof (struct expression
)
197 + EXP_ELEM_TO_BYTES (expout_size
));
198 expout
->language_defn
= lang
;
199 expout
->gdbarch
= gdbarch
;
202 /* See definition in parser-defs.h. */
205 reallocate_expout (void)
207 /* Record the actual number of expression elements, and then
208 reallocate the expression memory so that we free up any
211 expout
->nelts
= expout_ptr
;
212 expout
= xrealloc ((char *) expout
,
213 sizeof (struct expression
)
214 + EXP_ELEM_TO_BYTES (expout_ptr
));
217 /* Add one element to the end of the expression. */
219 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
220 a register through here. */
223 write_exp_elt (const union exp_element
*expelt
)
225 if (expout_ptr
>= expout_size
)
228 expout
= (struct expression
*)
229 xrealloc ((char *) expout
, sizeof (struct expression
)
230 + EXP_ELEM_TO_BYTES (expout_size
));
232 expout
->elts
[expout_ptr
++] = *expelt
;
236 write_exp_elt_opcode (enum exp_opcode expelt
)
238 union exp_element tmp
;
240 memset (&tmp
, 0, sizeof (union exp_element
));
242 write_exp_elt (&tmp
);
246 write_exp_elt_sym (struct symbol
*expelt
)
248 union exp_element tmp
;
250 memset (&tmp
, 0, sizeof (union exp_element
));
252 write_exp_elt (&tmp
);
256 write_exp_elt_block (const struct block
*b
)
258 union exp_element tmp
;
260 memset (&tmp
, 0, sizeof (union exp_element
));
262 write_exp_elt (&tmp
);
266 write_exp_elt_objfile (struct objfile
*objfile
)
268 union exp_element tmp
;
270 memset (&tmp
, 0, sizeof (union exp_element
));
271 tmp
.objfile
= objfile
;
272 write_exp_elt (&tmp
);
276 write_exp_elt_longcst (LONGEST expelt
)
278 union exp_element tmp
;
280 memset (&tmp
, 0, sizeof (union exp_element
));
281 tmp
.longconst
= expelt
;
282 write_exp_elt (&tmp
);
286 write_exp_elt_dblcst (DOUBLEST expelt
)
288 union exp_element tmp
;
290 memset (&tmp
, 0, sizeof (union exp_element
));
291 tmp
.doubleconst
= expelt
;
292 write_exp_elt (&tmp
);
296 write_exp_elt_decfloatcst (gdb_byte expelt
[16])
298 union exp_element tmp
;
301 for (index
= 0; index
< 16; index
++)
302 tmp
.decfloatconst
[index
] = expelt
[index
];
304 write_exp_elt (&tmp
);
308 write_exp_elt_type (struct type
*expelt
)
310 union exp_element tmp
;
312 memset (&tmp
, 0, sizeof (union exp_element
));
314 write_exp_elt (&tmp
);
318 write_exp_elt_intern (struct internalvar
*expelt
)
320 union exp_element tmp
;
322 memset (&tmp
, 0, sizeof (union exp_element
));
323 tmp
.internalvar
= expelt
;
324 write_exp_elt (&tmp
);
327 /* Add a string constant to the end of the expression.
329 String constants are stored by first writing an expression element
330 that contains the length of the string, then stuffing the string
331 constant itself into however many expression elements are needed
332 to hold it, and then writing another expression element that contains
333 the length of the string. I.e. an expression element at each end of
334 the string records the string length, so you can skip over the
335 expression elements containing the actual string bytes from either
336 end of the string. Note that this also allows gdb to handle
337 strings with embedded null bytes, as is required for some languages.
339 Don't be fooled by the fact that the string is null byte terminated,
340 this is strictly for the convenience of debugging gdb itself.
341 Gdb does not depend up the string being null terminated, since the
342 actual length is recorded in expression elements at each end of the
343 string. The null byte is taken into consideration when computing how
344 many expression elements are required to hold the string constant, of
349 write_exp_string (struct stoken str
)
351 int len
= str
.length
;
355 /* Compute the number of expression elements required to hold the string
356 (including a null byte terminator), along with one expression element
357 at each end to record the actual string length (not including the
358 null byte terminator). */
360 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
362 /* Ensure that we have enough available expression elements to store
365 if ((expout_ptr
+ lenelt
) >= expout_size
)
367 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
368 expout
= (struct expression
*)
369 xrealloc ((char *) expout
, (sizeof (struct expression
)
370 + EXP_ELEM_TO_BYTES (expout_size
)));
373 /* Write the leading length expression element (which advances the current
374 expression element index), then write the string constant followed by a
375 terminating null byte, and then write the trailing length expression
378 write_exp_elt_longcst ((LONGEST
) len
);
379 strdata
= (char *) &expout
->elts
[expout_ptr
];
380 memcpy (strdata
, str
.ptr
, len
);
381 *(strdata
+ len
) = '\0';
382 expout_ptr
+= lenelt
- 2;
383 write_exp_elt_longcst ((LONGEST
) len
);
386 /* Add a vector of string constants to the end of the expression.
388 This adds an OP_STRING operation, but encodes the contents
389 differently from write_exp_string. The language is expected to
390 handle evaluation of this expression itself.
392 After the usual OP_STRING header, TYPE is written into the
393 expression as a long constant. The interpretation of this field is
394 up to the language evaluator.
396 Next, each string in VEC is written. The length is written as a
397 long constant, followed by the contents of the string. */
400 write_exp_string_vector (int type
, struct stoken_vector
*vec
)
404 /* Compute the size. We compute the size in number of slots to
405 avoid issues with string padding. */
407 for (i
= 0; i
< vec
->len
; ++i
)
409 /* One slot for the length of this element, plus the number of
410 slots needed for this string. */
411 n_slots
+= 1 + BYTES_TO_EXP_ELEM (vec
->tokens
[i
].length
);
414 /* One more slot for the type of the string. */
417 /* Now compute a phony string length. */
418 len
= EXP_ELEM_TO_BYTES (n_slots
) - 1;
421 if ((expout_ptr
+ n_slots
) >= expout_size
)
423 expout_size
= max (expout_size
* 2, expout_ptr
+ n_slots
+ 10);
424 expout
= (struct expression
*)
425 xrealloc ((char *) expout
, (sizeof (struct expression
)
426 + EXP_ELEM_TO_BYTES (expout_size
)));
429 write_exp_elt_opcode (OP_STRING
);
430 write_exp_elt_longcst (len
);
431 write_exp_elt_longcst (type
);
433 for (i
= 0; i
< vec
->len
; ++i
)
435 write_exp_elt_longcst (vec
->tokens
[i
].length
);
436 memcpy (&expout
->elts
[expout_ptr
], vec
->tokens
[i
].ptr
,
437 vec
->tokens
[i
].length
);
438 expout_ptr
+= BYTES_TO_EXP_ELEM (vec
->tokens
[i
].length
);
441 write_exp_elt_longcst (len
);
442 write_exp_elt_opcode (OP_STRING
);
445 /* Add a bitstring constant to the end of the expression.
447 Bitstring constants are stored by first writing an expression element
448 that contains the length of the bitstring (in bits), then stuffing the
449 bitstring constant itself into however many expression elements are
450 needed to hold it, and then writing another expression element that
451 contains the length of the bitstring. I.e. an expression element at
452 each end of the bitstring records the bitstring length, so you can skip
453 over the expression elements containing the actual bitstring bytes from
454 either end of the bitstring. */
457 write_exp_bitstring (struct stoken str
)
459 int bits
= str
.length
; /* length in bits */
460 int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
464 /* Compute the number of expression elements required to hold the bitstring,
465 along with one expression element at each end to record the actual
466 bitstring length in bits. */
468 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
470 /* Ensure that we have enough available expression elements to store
473 if ((expout_ptr
+ lenelt
) >= expout_size
)
475 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
476 expout
= (struct expression
*)
477 xrealloc ((char *) expout
, (sizeof (struct expression
)
478 + EXP_ELEM_TO_BYTES (expout_size
)));
481 /* Write the leading length expression element (which advances the current
482 expression element index), then write the bitstring constant, and then
483 write the trailing length expression element. */
485 write_exp_elt_longcst ((LONGEST
) bits
);
486 strdata
= (char *) &expout
->elts
[expout_ptr
];
487 memcpy (strdata
, str
.ptr
, len
);
488 expout_ptr
+= lenelt
- 2;
489 write_exp_elt_longcst ((LONGEST
) bits
);
492 /* Add the appropriate elements for a minimal symbol to the end of
496 write_exp_msymbol (struct minimal_symbol
*msymbol
)
498 struct objfile
*objfile
= msymbol_objfile (msymbol
);
499 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
501 CORE_ADDR addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
502 struct obj_section
*section
= SYMBOL_OBJ_SECTION (msymbol
);
503 enum minimal_symbol_type type
= MSYMBOL_TYPE (msymbol
);
506 /* The minimal symbol might point to a function descriptor;
507 resolve it to the actual code address instead. */
508 pc
= gdbarch_convert_from_func_ptr_addr (gdbarch
, addr
, ¤t_target
);
511 struct minimal_symbol
*ifunc_msym
= lookup_minimal_symbol_by_pc (pc
);
513 /* In this case, assume we have a code symbol instead of
516 if (ifunc_msym
!= NULL
&& MSYMBOL_TYPE (ifunc_msym
) == mst_text_gnu_ifunc
517 && SYMBOL_VALUE_ADDRESS (ifunc_msym
) == pc
)
519 /* A function descriptor has been resolved but PC is still in the
520 STT_GNU_IFUNC resolver body (such as because inferior does not
521 run to be able to call it). */
523 type
= mst_text_gnu_ifunc
;
531 if (overlay_debugging
)
532 addr
= symbol_overlayed_address (addr
, section
);
534 write_exp_elt_opcode (OP_LONG
);
535 /* Let's make the type big enough to hold a 64-bit address. */
536 write_exp_elt_type (objfile_type (objfile
)->builtin_core_addr
);
537 write_exp_elt_longcst ((LONGEST
) addr
);
538 write_exp_elt_opcode (OP_LONG
);
540 if (section
&& section
->the_bfd_section
->flags
& SEC_THREAD_LOCAL
)
542 write_exp_elt_opcode (UNOP_MEMVAL_TLS
);
543 write_exp_elt_objfile (objfile
);
544 write_exp_elt_type (objfile_type (objfile
)->nodebug_tls_symbol
);
545 write_exp_elt_opcode (UNOP_MEMVAL_TLS
);
549 write_exp_elt_opcode (UNOP_MEMVAL
);
554 case mst_solib_trampoline
:
555 write_exp_elt_type (objfile_type (objfile
)->nodebug_text_symbol
);
558 case mst_text_gnu_ifunc
:
559 write_exp_elt_type (objfile_type (objfile
)
560 ->nodebug_text_gnu_ifunc_symbol
);
567 write_exp_elt_type (objfile_type (objfile
)->nodebug_data_symbol
);
570 case mst_slot_got_plt
:
571 write_exp_elt_type (objfile_type (objfile
)->nodebug_got_plt_symbol
);
575 write_exp_elt_type (objfile_type (objfile
)->nodebug_unknown_symbol
);
578 write_exp_elt_opcode (UNOP_MEMVAL
);
581 /* Mark the current index as the starting location of a structure
582 expression. This is used when completing on field names. */
585 mark_struct_expression (void)
587 gdb_assert (parse_completion
588 && expout_tag_completion_type
== TYPE_CODE_UNDEF
);
589 expout_last_struct
= expout_ptr
;
592 /* Indicate that the current parser invocation is completing a tag.
593 TAG is the type code of the tag, and PTR and LENGTH represent the
594 start of the tag name. */
597 mark_completion_tag (enum type_code tag
, const char *ptr
, int length
)
599 gdb_assert (parse_completion
600 && expout_tag_completion_type
== TYPE_CODE_UNDEF
601 && expout_completion_name
== NULL
602 && expout_last_struct
== -1);
603 gdb_assert (tag
== TYPE_CODE_UNION
604 || tag
== TYPE_CODE_STRUCT
605 || tag
== TYPE_CODE_CLASS
606 || tag
== TYPE_CODE_ENUM
);
607 expout_tag_completion_type
= tag
;
608 expout_completion_name
= xmalloc (length
+ 1);
609 memcpy (expout_completion_name
, ptr
, length
);
610 expout_completion_name
[length
] = '\0';
614 /* Recognize tokens that start with '$'. These include:
616 $regname A native register name or a "standard
619 $variable A convenience variable with a name chosen
622 $digits Value history with index <digits>, starting
623 from the first value which has index 1.
625 $$digits Value history with index <digits> relative
626 to the last value. I.e. $$0 is the last
627 value, $$1 is the one previous to that, $$2
628 is the one previous to $$1, etc.
630 $ | $0 | $$0 The last value in the value history.
632 $$ An abbreviation for the second to the last
633 value in the value history, I.e. $$1 */
636 write_dollar_variable (struct stoken str
)
638 struct symbol
*sym
= NULL
;
639 struct minimal_symbol
*msym
= NULL
;
640 struct internalvar
*isym
= NULL
;
642 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
643 and $$digits (equivalent to $<-digits> if you could type that). */
647 /* Double dollar means negate the number and add -1 as well.
648 Thus $$ alone means -1. */
649 if (str
.length
>= 2 && str
.ptr
[1] == '$')
656 /* Just dollars (one or two). */
660 /* Is the rest of the token digits? */
661 for (; i
< str
.length
; i
++)
662 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
666 i
= atoi (str
.ptr
+ 1 + negate
);
672 /* Handle tokens that refer to machine registers:
673 $ followed by a register name. */
674 i
= user_reg_map_name_to_regnum (parse_gdbarch
,
675 str
.ptr
+ 1, str
.length
- 1);
677 goto handle_register
;
679 /* Any names starting with $ are probably debugger internal variables. */
681 isym
= lookup_only_internalvar (copy_name (str
) + 1);
684 write_exp_elt_opcode (OP_INTERNALVAR
);
685 write_exp_elt_intern (isym
);
686 write_exp_elt_opcode (OP_INTERNALVAR
);
690 /* On some systems, such as HP-UX and hppa-linux, certain system routines
691 have names beginning with $ or $$. Check for those, first. */
693 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
697 write_exp_elt_opcode (OP_VAR_VALUE
);
698 write_exp_elt_block (block_found
); /* set by lookup_symbol */
699 write_exp_elt_sym (sym
);
700 write_exp_elt_opcode (OP_VAR_VALUE
);
703 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
706 write_exp_msymbol (msym
);
710 /* Any other names are assumed to be debugger internal variables. */
712 write_exp_elt_opcode (OP_INTERNALVAR
);
713 write_exp_elt_intern (create_internalvar (copy_name (str
) + 1));
714 write_exp_elt_opcode (OP_INTERNALVAR
);
717 write_exp_elt_opcode (OP_LAST
);
718 write_exp_elt_longcst ((LONGEST
) i
);
719 write_exp_elt_opcode (OP_LAST
);
722 write_exp_elt_opcode (OP_REGISTER
);
725 write_exp_string (str
);
726 write_exp_elt_opcode (OP_REGISTER
);
732 find_template_name_end (char *p
)
735 int just_seen_right
= 0;
736 int just_seen_colon
= 0;
737 int just_seen_space
= 0;
739 if (!p
|| (*p
!= '<'))
750 /* In future, may want to allow these?? */
753 depth
++; /* start nested template */
754 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
755 return 0; /* but not after : or :: or > or space */
758 if (just_seen_colon
|| just_seen_right
)
759 return 0; /* end a (nested?) template */
760 just_seen_right
= 1; /* but not after : or :: */
761 if (--depth
== 0) /* also disallow >>, insist on > > */
762 return ++p
; /* if outermost ended, return */
765 if (just_seen_space
|| (just_seen_colon
> 1))
766 return 0; /* nested class spec coming up */
767 just_seen_colon
++; /* we allow :: but not :::: */
772 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
773 (*p
>= 'A' && *p
<= 'Z') ||
774 (*p
>= '0' && *p
<= '9') ||
775 (*p
== '_') || (*p
== ',') || /* commas for template args */
776 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
777 (*p
== '(') || (*p
== ')') || /* function types */
778 (*p
== '[') || (*p
== ']'))) /* array types */
792 /* Return a null-terminated temporary copy of the name of a string token.
794 Tokens that refer to names do so with explicit pointer and length,
795 so they can share the storage that lexptr is parsing.
796 When it is necessary to pass a name to a function that expects
797 a null-terminated string, the substring is copied out
798 into a separate block of storage.
800 N.B. A single buffer is reused on each call. */
803 copy_name (struct stoken token
)
805 /* A temporary buffer for identifiers, so we can null-terminate them.
806 We allocate this with xrealloc. parse_exp_1 used to allocate with
807 alloca, using the size of the whole expression as a conservative
808 estimate of the space needed. However, macro expansion can
809 introduce names longer than the original expression; there's no
810 practical way to know beforehand how large that might be. */
811 static char *namecopy
;
812 static size_t namecopy_size
;
814 /* Make sure there's enough space for the token. */
815 if (namecopy_size
< token
.length
+ 1)
817 namecopy_size
= token
.length
+ 1;
818 namecopy
= xrealloc (namecopy
, token
.length
+ 1);
821 memcpy (namecopy
, token
.ptr
, token
.length
);
822 namecopy
[token
.length
] = 0;
828 /* See comments on parser-defs.h. */
831 prefixify_expression (struct expression
*expr
)
833 int len
= sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
834 struct expression
*temp
;
835 int inpos
= expr
->nelts
, outpos
= 0;
837 temp
= (struct expression
*) alloca (len
);
839 /* Copy the original expression into temp. */
840 memcpy (temp
, expr
, len
);
842 return prefixify_subexp (temp
, expr
, inpos
, outpos
);
845 /* Return the number of exp_elements in the postfix subexpression
846 of EXPR whose operator is at index ENDPOS - 1 in EXPR. */
849 length_of_subexp (struct expression
*expr
, int endpos
)
853 operator_length (expr
, endpos
, &oplen
, &args
);
857 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
864 /* Sets *OPLENP to the length of the operator whose (last) index is
865 ENDPOS - 1 in EXPR, and sets *ARGSP to the number of arguments that
869 operator_length (const struct expression
*expr
, int endpos
, int *oplenp
,
872 expr
->language_defn
->la_exp_desc
->operator_length (expr
, endpos
,
876 /* Default value for operator_length in exp_descriptor vectors. */
879 operator_length_standard (const struct expression
*expr
, int endpos
,
880 int *oplenp
, int *argsp
)
884 enum f90_range_type range_type
;
888 error (_("?error in operator_length_standard"));
890 i
= (int) expr
->elts
[endpos
- 1].opcode
;
896 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
897 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
911 case OP_VAR_ENTRY_VALUE
:
921 case OP_F77_UNDETERMINED_ARGLIST
:
923 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
927 oplen
= 4 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
931 case OP_OBJC_MSGCALL
: /* Objective C message (method) call. */
933 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
942 case UNOP_DYNAMIC_CAST
:
943 case UNOP_REINTERPRET_CAST
:
944 case UNOP_MEMVAL_TYPE
:
956 case UNOP_MEMVAL_TLS
:
976 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
977 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
982 case STRUCTOP_STRUCT
:
989 case OP_OBJC_NSSTRING
: /* Objective C Foundation Class
990 NSString constant. */
991 case OP_OBJC_SELECTOR
: /* Objective C "@selector" pseudo-op. */
993 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
994 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
999 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
1000 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
1010 case MULTI_SUBSCRIPT
:
1012 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
1015 case BINOP_ASSIGN_MODIFY
:
1028 range_type
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
1031 case LOW_BOUND_DEFAULT
:
1032 case HIGH_BOUND_DEFAULT
:
1035 case BOTH_BOUND_DEFAULT
:
1038 case NONE_BOUND_DEFAULT
:
1046 args
= 1 + (i
< (int) BINOP_END
);
1053 /* Copy the subexpression ending just before index INEND in INEXPR
1054 into OUTEXPR, starting at index OUTBEG.
1055 In the process, convert it from suffix to prefix form.
1056 If EXPOUT_LAST_STRUCT is -1, then this function always returns -1.
1057 Otherwise, it returns the index of the subexpression which is the
1058 left-hand-side of the expression at EXPOUT_LAST_STRUCT. */
1061 prefixify_subexp (struct expression
*inexpr
,
1062 struct expression
*outexpr
, int inend
, int outbeg
)
1070 operator_length (inexpr
, inend
, &oplen
, &args
);
1072 /* Copy the final operator itself, from the end of the input
1073 to the beginning of the output. */
1075 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1076 EXP_ELEM_TO_BYTES (oplen
));
1079 if (expout_last_struct
== inend
)
1080 result
= outbeg
- oplen
;
1082 /* Find the lengths of the arg subexpressions. */
1083 arglens
= (int *) alloca (args
* sizeof (int));
1084 for (i
= args
- 1; i
>= 0; i
--)
1086 oplen
= length_of_subexp (inexpr
, inend
);
1091 /* Now copy each subexpression, preserving the order of
1092 the subexpressions, but prefixifying each one.
1093 In this loop, inend starts at the beginning of
1094 the expression this level is working on
1095 and marches forward over the arguments.
1096 outbeg does similarly in the output. */
1097 for (i
= 0; i
< args
; i
++)
1103 r
= prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1106 /* Return immediately. We probably have only parsed a
1107 partial expression, so we don't want to try to reverse
1108 the other operands. */
1117 /* Read an expression from the string *STRINGPTR points to,
1118 parse it, and return a pointer to a struct expression that we malloc.
1119 Use block BLOCK as the lexical context for variable names;
1120 if BLOCK is zero, use the block of the selected stack frame.
1121 Meanwhile, advance *STRINGPTR to point after the expression,
1122 at the first nonwhite character that is not part of the expression
1123 (possibly a null character).
1125 If COMMA is nonzero, stop if a comma is reached. */
1128 parse_exp_1 (char **stringptr
, CORE_ADDR pc
, const struct block
*block
,
1131 return parse_exp_in_context (stringptr
, pc
, block
, comma
, 0, NULL
);
1134 /* As for parse_exp_1, except that if VOID_CONTEXT_P, then
1135 no value is expected from the expression.
1136 OUT_SUBEXP is set when attempting to complete a field name; in this
1137 case it is set to the index of the subexpression on the
1138 left-hand-side of the struct op. If not doing such completion, it
1139 is left untouched. */
1141 static struct expression
*
1142 parse_exp_in_context (char **stringptr
, CORE_ADDR pc
, const struct block
*block
,
1143 int comma
, int void_context_p
, int *out_subexp
)
1145 volatile struct gdb_exception except
;
1146 struct cleanup
*old_chain
;
1147 const struct language_defn
*lang
= NULL
;
1150 lexptr
= *stringptr
;
1154 type_stack
.depth
= 0;
1155 expout_last_struct
= -1;
1156 expout_tag_completion_type
= TYPE_CODE_UNDEF
;
1157 xfree (expout_completion_name
);
1158 expout_completion_name
= NULL
;
1160 comma_terminates
= comma
;
1162 if (lexptr
== 0 || *lexptr
== 0)
1163 error_no_arg (_("expression to compute"));
1165 old_chain
= make_cleanup (free_funcalls
, 0 /*ignore*/);
1168 expression_context_block
= block
;
1170 /* If no context specified, try using the current frame, if any. */
1171 if (!expression_context_block
)
1172 expression_context_block
= get_selected_block (&expression_context_pc
);
1174 expression_context_pc
= BLOCK_START (expression_context_block
);
1176 expression_context_pc
= pc
;
1178 /* Fall back to using the current source static context, if any. */
1180 if (!expression_context_block
)
1182 struct symtab_and_line cursal
= get_current_source_symtab_and_line ();
1184 expression_context_block
1185 = BLOCKVECTOR_BLOCK (BLOCKVECTOR (cursal
.symtab
), STATIC_BLOCK
);
1186 if (expression_context_block
)
1187 expression_context_pc
= BLOCK_START (expression_context_block
);
1190 if (language_mode
== language_mode_auto
&& block
!= NULL
)
1192 /* Find the language associated to the given context block.
1193 Default to the current language if it can not be determined.
1195 Note that using the language corresponding to the current frame
1196 can sometimes give unexpected results. For instance, this
1197 routine is often called several times during the inferior
1198 startup phase to re-parse breakpoint expressions after
1199 a new shared library has been loaded. The language associated
1200 to the current frame at this moment is not relevant for
1201 the breakpoint. Using it would therefore be silly, so it seems
1202 better to rely on the current language rather than relying on
1203 the current frame language to parse the expression. That's why
1204 we do the following language detection only if the context block
1205 has been specifically provided. */
1206 struct symbol
*func
= block_linkage_function (block
);
1209 lang
= language_def (SYMBOL_LANGUAGE (func
));
1210 if (lang
== NULL
|| lang
->la_language
== language_unknown
)
1211 lang
= current_language
;
1214 lang
= current_language
;
1216 initialize_expout (10, lang
, get_current_arch ());
1218 TRY_CATCH (except
, RETURN_MASK_ALL
)
1220 if (lang
->la_parser ())
1221 lang
->la_error (NULL
);
1223 if (except
.reason
< 0)
1225 if (! parse_completion
)
1228 throw_exception (except
);
1232 discard_cleanups (old_chain
);
1234 reallocate_expout ();
1236 /* Convert expression from postfix form as generated by yacc
1237 parser, to a prefix form. */
1239 if (expressiondebug
)
1240 dump_raw_expression (expout
, gdb_stdlog
,
1241 "before conversion to prefix form");
1243 subexp
= prefixify_expression (expout
);
1245 *out_subexp
= subexp
;
1247 lang
->la_post_parser (&expout
, void_context_p
);
1249 if (expressiondebug
)
1250 dump_prefix_expression (expout
, gdb_stdlog
);
1252 *stringptr
= lexptr
;
1256 /* Parse STRING as an expression, and complain if this fails
1257 to use up all of the contents of STRING. */
1260 parse_expression (char *string
)
1262 struct expression
*exp
;
1264 exp
= parse_exp_1 (&string
, 0, 0, 0);
1266 error (_("Junk after end of expression."));
1270 /* Parse STRING as an expression. If parsing ends in the middle of a
1271 field reference, return the type of the left-hand-side of the
1272 reference; furthermore, if the parsing ends in the field name,
1273 return the field name in *NAME. If the parsing ends in the middle
1274 of a field reference, but the reference is somehow invalid, throw
1275 an exception. In all other cases, return NULL. Returned non-NULL
1276 *NAME must be freed by the caller. */
1279 parse_expression_for_completion (char *string
, char **name
,
1280 enum type_code
*code
)
1282 struct expression
*exp
= NULL
;
1285 volatile struct gdb_exception except
;
1287 TRY_CATCH (except
, RETURN_MASK_ERROR
)
1289 parse_completion
= 1;
1290 exp
= parse_exp_in_context (&string
, 0, 0, 0, 0, &subexp
);
1292 parse_completion
= 0;
1293 if (except
.reason
< 0 || ! exp
)
1296 if (expout_tag_completion_type
!= TYPE_CODE_UNDEF
)
1298 *code
= expout_tag_completion_type
;
1299 *name
= expout_completion_name
;
1300 expout_completion_name
= NULL
;
1304 if (expout_last_struct
== -1)
1310 *name
= extract_field_op (exp
, &subexp
);
1317 /* This might throw an exception. If so, we want to let it
1319 val
= evaluate_subexpression_type (exp
, subexp
);
1320 /* (*NAME) is a part of the EXP memory block freed below. */
1321 *name
= xstrdup (*name
);
1324 return value_type (val
);
1327 /* A post-parser that does nothing. */
1330 null_post_parser (struct expression
**exp
, int void_context_p
)
1334 /* Parse floating point value P of length LEN.
1335 Return 0 (false) if invalid, 1 (true) if valid.
1336 The successfully parsed number is stored in D.
1337 *SUFFIX points to the suffix of the number in P.
1339 NOTE: This accepts the floating point syntax that sscanf accepts. */
1342 parse_float (const char *p
, int len
, DOUBLEST
*d
, const char **suffix
)
1347 copy
= xmalloc (len
+ 1);
1348 memcpy (copy
, p
, len
);
1351 num
= sscanf (copy
, "%" DOUBLEST_SCAN_FORMAT
"%n", d
, &n
);
1354 /* The sscanf man page suggests not making any assumptions on the effect
1355 of %n on the result, so we don't.
1356 That is why we simply test num == 0. */
1364 /* Parse floating point value P of length LEN, using the C syntax for floats.
1365 Return 0 (false) if invalid, 1 (true) if valid.
1366 The successfully parsed number is stored in *D.
1367 Its type is taken from builtin_type (gdbarch) and is stored in *T. */
1370 parse_c_float (struct gdbarch
*gdbarch
, const char *p
, int len
,
1371 DOUBLEST
*d
, struct type
**t
)
1375 const struct builtin_type
*builtin_types
= builtin_type (gdbarch
);
1377 if (! parse_float (p
, len
, d
, &suffix
))
1380 suffix_len
= p
+ len
- suffix
;
1382 if (suffix_len
== 0)
1383 *t
= builtin_types
->builtin_double
;
1384 else if (suffix_len
== 1)
1386 /* Handle suffixes: 'f' for float, 'l' for long double. */
1387 if (tolower (*suffix
) == 'f')
1388 *t
= builtin_types
->builtin_float
;
1389 else if (tolower (*suffix
) == 'l')
1390 *t
= builtin_types
->builtin_long_double
;
1400 /* Stuff for maintaining a stack of types. Currently just used by C, but
1401 probably useful for any language which declares its types "backwards". */
1403 /* Ensure that there are HOWMUCH open slots on the type stack STACK. */
1406 type_stack_reserve (struct type_stack
*stack
, int howmuch
)
1408 if (stack
->depth
+ howmuch
>= stack
->size
)
1411 if (stack
->size
< howmuch
)
1412 stack
->size
= howmuch
;
1413 stack
->elements
= xrealloc (stack
->elements
,
1414 stack
->size
* sizeof (union type_stack_elt
));
1418 /* Ensure that there is a single open slot in the global type stack. */
1421 check_type_stack_depth (void)
1423 type_stack_reserve (&type_stack
, 1);
1426 /* A helper function for insert_type and insert_type_address_space.
1427 This does work of expanding the type stack and inserting the new
1428 element, ELEMENT, into the stack at location SLOT. */
1431 insert_into_type_stack (int slot
, union type_stack_elt element
)
1433 check_type_stack_depth ();
1435 if (slot
< type_stack
.depth
)
1436 memmove (&type_stack
.elements
[slot
+ 1], &type_stack
.elements
[slot
],
1437 (type_stack
.depth
- slot
) * sizeof (union type_stack_elt
));
1438 type_stack
.elements
[slot
] = element
;
1442 /* Insert a new type, TP, at the bottom of the type stack. If TP is
1443 tp_pointer or tp_reference, it is inserted at the bottom. If TP is
1444 a qualifier, it is inserted at slot 1 (just above a previous
1445 tp_pointer) if there is anything on the stack, or simply pushed if
1446 the stack is empty. Other values for TP are invalid. */
1449 insert_type (enum type_pieces tp
)
1451 union type_stack_elt element
;
1454 gdb_assert (tp
== tp_pointer
|| tp
== tp_reference
1455 || tp
== tp_const
|| tp
== tp_volatile
);
1457 /* If there is anything on the stack (we know it will be a
1458 tp_pointer), insert the qualifier above it. Otherwise, simply
1459 push this on the top of the stack. */
1460 if (type_stack
.depth
&& (tp
== tp_const
|| tp
== tp_volatile
))
1466 insert_into_type_stack (slot
, element
);
1470 push_type (enum type_pieces tp
)
1472 check_type_stack_depth ();
1473 type_stack
.elements
[type_stack
.depth
++].piece
= tp
;
1477 push_type_int (int n
)
1479 check_type_stack_depth ();
1480 type_stack
.elements
[type_stack
.depth
++].int_val
= n
;
1483 /* Insert a tp_space_identifier and the corresponding address space
1484 value into the stack. STRING is the name of an address space, as
1485 recognized by address_space_name_to_int. If the stack is empty,
1486 the new elements are simply pushed. If the stack is not empty,
1487 this function assumes that the first item on the stack is a
1488 tp_pointer, and the new values are inserted above the first
1492 insert_type_address_space (char *string
)
1494 union type_stack_elt element
;
1497 /* If there is anything on the stack (we know it will be a
1498 tp_pointer), insert the address space qualifier above it.
1499 Otherwise, simply push this on the top of the stack. */
1500 if (type_stack
.depth
)
1505 element
.piece
= tp_space_identifier
;
1506 insert_into_type_stack (slot
, element
);
1507 element
.int_val
= address_space_name_to_int (parse_gdbarch
, string
);
1508 insert_into_type_stack (slot
, element
);
1514 if (type_stack
.depth
)
1515 return type_stack
.elements
[--type_stack
.depth
].piece
;
1522 if (type_stack
.depth
)
1523 return type_stack
.elements
[--type_stack
.depth
].int_val
;
1524 /* "Can't happen". */
1528 /* Pop a type list element from the global type stack. */
1530 static VEC (type_ptr
) *
1533 gdb_assert (type_stack
.depth
);
1534 return type_stack
.elements
[--type_stack
.depth
].typelist_val
;
1537 /* Pop a type_stack element from the global type stack. */
1539 static struct type_stack
*
1540 pop_type_stack (void)
1542 gdb_assert (type_stack
.depth
);
1543 return type_stack
.elements
[--type_stack
.depth
].stack_val
;
1546 /* Append the elements of the type stack FROM to the type stack TO.
1547 Always returns TO. */
1550 append_type_stack (struct type_stack
*to
, struct type_stack
*from
)
1552 type_stack_reserve (to
, from
->depth
);
1554 memcpy (&to
->elements
[to
->depth
], &from
->elements
[0],
1555 from
->depth
* sizeof (union type_stack_elt
));
1556 to
->depth
+= from
->depth
;
1561 /* Push the type stack STACK as an element on the global type stack. */
1564 push_type_stack (struct type_stack
*stack
)
1566 check_type_stack_depth ();
1567 type_stack
.elements
[type_stack
.depth
++].stack_val
= stack
;
1568 push_type (tp_type_stack
);
1571 /* Copy the global type stack into a newly allocated type stack and
1572 return it. The global stack is cleared. The returned type stack
1573 must be freed with type_stack_cleanup. */
1576 get_type_stack (void)
1578 struct type_stack
*result
= XNEW (struct type_stack
);
1580 *result
= type_stack
;
1581 type_stack
.depth
= 0;
1582 type_stack
.size
= 0;
1583 type_stack
.elements
= NULL
;
1588 /* A cleanup function that destroys a single type stack. */
1591 type_stack_cleanup (void *arg
)
1593 struct type_stack
*stack
= arg
;
1595 xfree (stack
->elements
);
1599 /* Push a function type with arguments onto the global type stack.
1600 LIST holds the argument types. If the final item in LIST is NULL,
1601 then the function will be varargs. */
1604 push_typelist (VEC (type_ptr
) *list
)
1606 check_type_stack_depth ();
1607 type_stack
.elements
[type_stack
.depth
++].typelist_val
= list
;
1608 push_type (tp_function_with_arguments
);
1611 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1612 as modified by all the stuff on the stack. */
1614 follow_types (struct type
*follow_type
)
1618 int make_volatile
= 0;
1619 int make_addr_space
= 0;
1623 switch (pop_type ())
1628 follow_type
= make_cv_type (make_const
,
1629 TYPE_VOLATILE (follow_type
),
1632 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1635 if (make_addr_space
)
1636 follow_type
= make_type_with_address_space (follow_type
,
1638 make_const
= make_volatile
= 0;
1639 make_addr_space
= 0;
1647 case tp_space_identifier
:
1648 make_addr_space
= pop_type_int ();
1651 follow_type
= lookup_pointer_type (follow_type
);
1653 follow_type
= make_cv_type (make_const
,
1654 TYPE_VOLATILE (follow_type
),
1657 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1660 if (make_addr_space
)
1661 follow_type
= make_type_with_address_space (follow_type
,
1663 make_const
= make_volatile
= 0;
1664 make_addr_space
= 0;
1667 follow_type
= lookup_reference_type (follow_type
);
1669 follow_type
= make_cv_type (make_const
,
1670 TYPE_VOLATILE (follow_type
),
1673 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1676 if (make_addr_space
)
1677 follow_type
= make_type_with_address_space (follow_type
,
1679 make_const
= make_volatile
= 0;
1680 make_addr_space
= 0;
1683 array_size
= pop_type_int ();
1684 /* FIXME-type-allocation: need a way to free this type when we are
1687 lookup_array_range_type (follow_type
,
1688 0, array_size
>= 0 ? array_size
- 1 : 0);
1690 TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (follow_type
) = 1;
1693 /* FIXME-type-allocation: need a way to free this type when we are
1695 follow_type
= lookup_function_type (follow_type
);
1698 case tp_function_with_arguments
:
1700 VEC (type_ptr
) *args
= pop_typelist ();
1703 = lookup_function_type_with_arguments (follow_type
,
1704 VEC_length (type_ptr
, args
),
1705 VEC_address (type_ptr
,
1707 VEC_free (type_ptr
, args
);
1713 struct type_stack
*stack
= pop_type_stack ();
1714 /* Sort of ugly, but not really much worse than the
1716 struct type_stack save
= type_stack
;
1718 type_stack
= *stack
;
1719 follow_type
= follow_types (follow_type
);
1720 gdb_assert (type_stack
.depth
== 0);
1726 gdb_assert_not_reached ("unrecognized tp_ value in follow_types");
1731 /* This function avoids direct calls to fprintf
1732 in the parser generated debug code. */
1734 parser_fprintf (FILE *x
, const char *y
, ...)
1740 vfprintf_unfiltered (gdb_stderr
, y
, args
);
1743 fprintf_unfiltered (gdb_stderr
, " Unknown FILE used.\n");
1744 vfprintf_unfiltered (gdb_stderr
, y
, args
);
1749 /* Implementation of the exp_descriptor method operator_check. */
1752 operator_check_standard (struct expression
*exp
, int pos
,
1753 int (*objfile_func
) (struct objfile
*objfile
,
1757 const union exp_element
*const elts
= exp
->elts
;
1758 struct type
*type
= NULL
;
1759 struct objfile
*objfile
= NULL
;
1761 /* Extended operators should have been already handled by exp_descriptor
1762 iterate method of its specific language. */
1763 gdb_assert (elts
[pos
].opcode
< OP_EXTENDED0
);
1765 /* Track the callers of write_exp_elt_type for this table. */
1767 switch (elts
[pos
].opcode
)
1780 type
= elts
[pos
+ 1].type
;
1785 LONGEST arg
, nargs
= elts
[pos
+ 1].longconst
;
1787 for (arg
= 0; arg
< nargs
; arg
++)
1789 struct type
*type
= elts
[pos
+ 2 + arg
].type
;
1790 struct objfile
*objfile
= TYPE_OBJFILE (type
);
1792 if (objfile
&& (*objfile_func
) (objfile
, data
))
1798 case UNOP_MEMVAL_TLS
:
1799 objfile
= elts
[pos
+ 1].objfile
;
1800 type
= elts
[pos
+ 2].type
;
1805 const struct block
*const block
= elts
[pos
+ 1].block
;
1806 const struct symbol
*const symbol
= elts
[pos
+ 2].symbol
;
1808 /* Check objfile where the variable itself is placed.
1809 SYMBOL_OBJ_SECTION (symbol) may be NULL. */
1810 if ((*objfile_func
) (SYMBOL_SYMTAB (symbol
)->objfile
, data
))
1813 /* Check objfile where is placed the code touching the variable. */
1814 objfile
= lookup_objfile_from_block (block
);
1816 type
= SYMBOL_TYPE (symbol
);
1821 /* Invoke callbacks for TYPE and OBJFILE if they were set as non-NULL. */
1823 if (type
&& TYPE_OBJFILE (type
)
1824 && (*objfile_func
) (TYPE_OBJFILE (type
), data
))
1826 if (objfile
&& (*objfile_func
) (objfile
, data
))
1832 /* Call OBJFILE_FUNC for any TYPE and OBJFILE found being referenced by EXP.
1833 The functions are never called with NULL OBJFILE. Functions get passed an
1834 arbitrary caller supplied DATA pointer. If any of the functions returns
1835 non-zero value then (any other) non-zero value is immediately returned to
1836 the caller. Otherwise zero is returned after iterating through whole EXP.
1840 exp_iterate (struct expression
*exp
,
1841 int (*objfile_func
) (struct objfile
*objfile
, void *data
),
1846 for (endpos
= exp
->nelts
; endpos
> 0; )
1848 int pos
, args
, oplen
= 0;
1850 operator_length (exp
, endpos
, &oplen
, &args
);
1851 gdb_assert (oplen
> 0);
1853 pos
= endpos
- oplen
;
1854 if (exp
->language_defn
->la_exp_desc
->operator_check (exp
, pos
,
1855 objfile_func
, data
))
1864 /* Helper for exp_uses_objfile. */
1867 exp_uses_objfile_iter (struct objfile
*exp_objfile
, void *objfile_voidp
)
1869 struct objfile
*objfile
= objfile_voidp
;
1871 if (exp_objfile
->separate_debug_objfile_backlink
)
1872 exp_objfile
= exp_objfile
->separate_debug_objfile_backlink
;
1874 return exp_objfile
== objfile
;
1877 /* Return 1 if EXP uses OBJFILE (and will become dangling when OBJFILE
1878 is unloaded), otherwise return 0. OBJFILE must not be a separate debug info
1882 exp_uses_objfile (struct expression
*exp
, struct objfile
*objfile
)
1884 gdb_assert (objfile
->separate_debug_objfile_backlink
== NULL
);
1886 return exp_iterate (exp
, exp_uses_objfile_iter
, objfile
);
1890 _initialize_parse (void)
1892 type_stack
.size
= 0;
1893 type_stack
.depth
= 0;
1894 type_stack
.elements
= NULL
;
1896 add_setshow_zuinteger_cmd ("expression", class_maintenance
,
1898 _("Set expression debugging."),
1899 _("Show expression debugging."),
1900 _("When non-zero, the internal representation "
1901 "of expressions will be printed."),
1903 show_expressiondebug
,
1904 &setdebuglist
, &showdebuglist
);
1905 add_setshow_boolean_cmd ("parser", class_maintenance
,
1907 _("Set parser debugging."),
1908 _("Show parser debugging."),
1909 _("When non-zero, expression parser "
1910 "tracing will be enabled."),
1913 &setdebuglist
, &showdebuglist
);