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1 /* Output the generated parsing program for Bison.
2
3 Copyright (C) 1984, 1986, 1989, 1992, 2000-2010 Free Software
4 Foundation, Inc.
5
6 This file is part of Bison, the GNU Compiler Compiler.
7
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20
21 #include <config.h>
22 #include "system.h"
23
24 #include <assert.h>
25 #include <configmake.h>
26 #include <error.h>
27 #include <get-errno.h>
28 #include <pipe.h>
29 #include <quotearg.h>
30 #include <timevar.h>
31 #include <wait-process.h>
32
33 #include "complain.h"
34 #include "files.h"
35 #include "getargs.h"
36 #include "gram.h"
37 #include "muscle_tab.h"
38 #include "output.h"
39 #include "reader.h"
40 #include "scan-code.h" /* max_left_semantic_context */
41 #include "scan-skel.h"
42 #include "symtab.h"
43 #include "tables.h"
44
45 # define ARRAY_CARDINALITY(Array) (sizeof (Array) / sizeof *(Array))
46
47 static struct obstack format_obstack;
48
49
50 /*-------------------------------------------------------------------.
51 | Create a function NAME which associates to the muscle NAME the |
52 | result of formatting the FIRST and then TABLE_DATA[BEGIN..END[ (of |
53 | TYPE), and to the muscle NAME_max, the max value of the |
54 | TABLE_DATA. |
55 `-------------------------------------------------------------------*/
56
57
58 #define GENERATE_MUSCLE_INSERT_TABLE(Name, Type) \
59 \
60 static void \
61 Name (char const *name, \
62 Type *table_data, \
63 Type first, \
64 int begin, \
65 int end) \
66 { \
67 Type min = first; \
68 Type max = first; \
69 long int lmin; \
70 long int lmax; \
71 int i; \
72 int j = 1; \
73 \
74 obstack_fgrow1 (&format_obstack, "%6d", first); \
75 for (i = begin; i < end; ++i) \
76 { \
77 obstack_1grow (&format_obstack, ','); \
78 if (j >= 10) \
79 { \
80 obstack_sgrow (&format_obstack, "\n "); \
81 j = 1; \
82 } \
83 else \
84 ++j; \
85 obstack_fgrow1 (&format_obstack, "%6d", table_data[i]); \
86 if (table_data[i] < min) \
87 min = table_data[i]; \
88 if (max < table_data[i]) \
89 max = table_data[i]; \
90 } \
91 obstack_1grow (&format_obstack, 0); \
92 muscle_insert (name, obstack_finish (&format_obstack)); \
93 \
94 lmin = min; \
95 lmax = max; \
96 /* Build `NAME_min' and `NAME_max' in the obstack. */ \
97 obstack_fgrow1 (&format_obstack, "%s_min", name); \
98 obstack_1grow (&format_obstack, 0); \
99 MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), lmin); \
100 obstack_fgrow1 (&format_obstack, "%s_max", name); \
101 obstack_1grow (&format_obstack, 0); \
102 MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), lmax); \
103 }
104
105 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_unsigned_int_table, unsigned int)
106 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_int_table, int)
107 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_base_table, base_number)
108 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_rule_number_table, rule_number)
109 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_symbol_number_table, symbol_number)
110 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_item_number_table, item_number)
111 GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_state_number_table, state_number)
112
113
114 /*--------------------------------------------------------------------.
115 | Print to OUT a representation of STRING escaped both for C and M4. |
116 `--------------------------------------------------------------------*/
117
118 static void
119 escaped_output (FILE *out, char const *string)
120 {
121 char const *p;
122 fprintf (out, "[[");
123
124 for (p = quotearg_style (c_quoting_style, string); *p; p++)
125 switch (*p)
126 {
127 case '$': fputs ("$][", out); break;
128 case '@': fputs ("@@", out); break;
129 case '[': fputs ("@{", out); break;
130 case ']': fputs ("@}", out); break;
131 default: fputc (*p, out); break;
132 }
133
134 fprintf (out, "]]");
135 }
136
137
138 /*------------------------------------------------------------------.
139 | Prepare the muscles related to the symbols: translate, tname, and |
140 | toknum. |
141 `------------------------------------------------------------------*/
142
143 static void
144 prepare_symbols (void)
145 {
146 MUSCLE_INSERT_BOOL ("token_table", token_table_flag);
147 MUSCLE_INSERT_INT ("tokens_number", ntokens);
148 MUSCLE_INSERT_INT ("nterms_number", nvars);
149 MUSCLE_INSERT_INT ("undef_token_number", undeftoken->number);
150 MUSCLE_INSERT_INT ("user_token_number_max", max_user_token_number);
151
152 muscle_insert_symbol_number_table ("translate",
153 token_translations,
154 token_translations[0],
155 1, max_user_token_number + 1);
156
157 /* tname -- token names. */
158 {
159 int i;
160 /* We assume that the table will be output starting at column 2. */
161 int j = 2;
162 struct quoting_options *qo = clone_quoting_options (0);
163 set_quoting_style (qo, c_quoting_style);
164 set_quoting_flags (qo, QA_SPLIT_TRIGRAPHS);
165 for (i = 0; i < nsyms; i++)
166 {
167 char *cp = quotearg_alloc (symbols[i]->tag, -1, qo);
168 /* Width of the next token, including the two quotes, the
169 comma and the space. */
170 int width = strlen (cp) + 2;
171
172 if (j + width > 75)
173 {
174 obstack_sgrow (&format_obstack, "\n ");
175 j = 1;
176 }
177
178 if (i)
179 obstack_1grow (&format_obstack, ' ');
180 MUSCLE_OBSTACK_SGROW (&format_obstack, cp);
181 free (cp);
182 obstack_1grow (&format_obstack, ',');
183 j += width;
184 }
185 free (qo);
186 obstack_sgrow (&format_obstack, " ]b4_null[");
187
188 /* Finish table and store. */
189 obstack_1grow (&format_obstack, 0);
190 muscle_insert ("tname", obstack_finish (&format_obstack));
191 }
192
193 /* Output YYTOKNUM. */
194 {
195 int i;
196 int *values = xnmalloc (ntokens, sizeof *values);
197 for (i = 0; i < ntokens; ++i)
198 values[i] = symbols[i]->user_token_number;
199 muscle_insert_int_table ("toknum", values,
200 values[0], 1, ntokens);
201 free (values);
202 }
203 }
204
205
206 /*-------------------------------------------------------------.
207 | Prepare the muscles related to the rules: rhs, prhs, r1, r2, |
208 | rline, dprec, merger. |
209 `-------------------------------------------------------------*/
210
211 static void
212 prepare_rules (void)
213 {
214 rule_number r;
215 unsigned int i = 0;
216 item_number *rhs = xnmalloc (nritems, sizeof *rhs);
217 unsigned int *prhs = xnmalloc (nrules, sizeof *prhs);
218 unsigned int *rline = xnmalloc (nrules, sizeof *rline);
219 symbol_number *r1 = xnmalloc (nrules, sizeof *r1);
220 unsigned int *r2 = xnmalloc (nrules, sizeof *r2);
221 int *dprec = xnmalloc (nrules, sizeof *dprec);
222 int *merger = xnmalloc (nrules, sizeof *merger);
223
224 for (r = 0; r < nrules; ++r)
225 {
226 item_number *rhsp = NULL;
227 /* Index of rule R in RHS. */
228 prhs[r] = i;
229 /* RHS of the rule R. */
230 for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
231 rhs[i++] = *rhsp;
232 /* LHS of the rule R. */
233 r1[r] = rules[r].lhs->number;
234 /* Length of rule R's RHS. */
235 r2[r] = i - prhs[r];
236 /* Separator in RHS. */
237 rhs[i++] = -1;
238 /* Line where rule was defined. */
239 rline[r] = rules[r].location.start.line;
240 /* Dynamic precedence (GLR). */
241 dprec[r] = rules[r].dprec;
242 /* Merger-function index (GLR). */
243 merger[r] = rules[r].merger;
244 }
245 aver (i == nritems);
246
247 muscle_insert_item_number_table ("rhs", rhs, ritem[0], 1, nritems);
248 muscle_insert_unsigned_int_table ("prhs", prhs, 0, 0, nrules);
249 muscle_insert_unsigned_int_table ("rline", rline, 0, 0, nrules);
250 muscle_insert_symbol_number_table ("r1", r1, 0, 0, nrules);
251 muscle_insert_unsigned_int_table ("r2", r2, 0, 0, nrules);
252 muscle_insert_int_table ("dprec", dprec, 0, 0, nrules);
253 muscle_insert_int_table ("merger", merger, 0, 0, nrules);
254
255 MUSCLE_INSERT_INT ("rules_number", nrules);
256 MUSCLE_INSERT_INT ("max_left_semantic_context", max_left_semantic_context);
257
258 free (rhs);
259 free (prhs);
260 free (rline);
261 free (r1);
262 free (r2);
263 free (dprec);
264 free (merger);
265 }
266
267 /*--------------------------------------------.
268 | Prepare the muscles related to the states. |
269 `--------------------------------------------*/
270
271 static void
272 prepare_states (void)
273 {
274 state_number i;
275 symbol_number *values = xnmalloc (nstates, sizeof *values);
276 for (i = 0; i < nstates; ++i)
277 values[i] = states[i]->accessing_symbol;
278 muscle_insert_symbol_number_table ("stos", values,
279 0, 1, nstates);
280 free (values);
281
282 MUSCLE_INSERT_INT ("last", high);
283 MUSCLE_INSERT_INT ("final_state_number", final_state->number);
284 MUSCLE_INSERT_INT ("states_number", nstates);
285 }
286
287
288
289 /*---------------------------------.
290 | Output the user actions to OUT. |
291 `---------------------------------*/
292
293 static void
294 user_actions_output (FILE *out)
295 {
296 rule_number r;
297
298 fputs ("m4_define([b4_actions], \n[", out);
299 for (r = 0; r < nrules; ++r)
300 if (rules[r].action)
301 {
302 fprintf (out, "b4_case(%d, [b4_syncline(%d, ", r + 1,
303 rules[r].action_location.start.line);
304 escaped_output (out, rules[r].action_location.start.file);
305 fprintf (out, ")\n[ %s]])\n\n", rules[r].action);
306 }
307 fputs ("])\n\n", out);
308 }
309
310 /*--------------------------------------.
311 | Output the merge functions to OUT. |
312 `--------------------------------------*/
313
314 static void
315 merger_output (FILE *out)
316 {
317 int n;
318 merger_list* p;
319
320 fputs ("m4_define([b4_mergers], \n[[", out);
321 for (n = 1, p = merge_functions; p != NULL; n += 1, p = p->next)
322 {
323 if (p->type[0] == '\0')
324 fprintf (out, " case %d: *yy0 = %s (*yy0, *yy1); break;\n",
325 n, p->name);
326 else
327 fprintf (out, " case %d: yy0->%s = %s (*yy0, *yy1); break;\n",
328 n, p->type, p->name);
329 }
330 fputs ("]])\n\n", out);
331 }
332
333 /*--------------------------------------.
334 | Output the tokens definition to OUT. |
335 `--------------------------------------*/
336
337 static void
338 token_definitions_output (FILE *out)
339 {
340 int i;
341 char const *sep = "";
342
343 fputs ("m4_define([b4_tokens], \n[", out);
344 for (i = 0; i < ntokens; ++i)
345 {
346 symbol *sym = symbols[i];
347 int number = sym->user_token_number;
348
349 /* At this stage, if there are literal aliases, they are part of
350 SYMBOLS, so we should not find symbols which are the aliases
351 here. */
352 aver (number != USER_NUMBER_ALIAS);
353
354 /* Skip error token. */
355 if (sym == errtoken)
356 continue;
357
358 /* If this string has an alias, then it is necessarily the alias
359 which is to be output. */
360 if (sym->alias)
361 sym = sym->alias;
362
363 /* Don't output literal chars or strings (when defined only as a
364 string). Note that must be done after the alias resolution:
365 think about `%token 'f' "f"'. */
366 if (sym->tag[0] == '\'' || sym->tag[0] == '\"')
367 continue;
368
369 /* Don't #define nonliteral tokens whose names contain periods
370 or '$' (as does the default value of the EOF token). */
371 if (strchr (sym->tag, '.') || strchr (sym->tag, '$'))
372 continue;
373
374 fprintf (out, "%s[[[%s]], %d]",
375 sep, sym->tag, number);
376 sep = ",\n";
377 }
378 fputs ("])\n\n", out);
379 }
380
381
382 /*---------------------------------------------------.
383 | Output the symbol destructors or printers to OUT. |
384 `---------------------------------------------------*/
385
386 static void
387 symbol_code_props_output (FILE *out, char const *what,
388 code_props const *(*get)(symbol const *))
389 {
390 int i;
391 char const *sep = "";
392
393 fputs ("m4_define([b4_symbol_", out);
394 fputs (what, out);
395 fputs ("], \n[", out);
396 for (i = 0; i < nsyms; ++i)
397 {
398 symbol *sym = symbols[i];
399 char const *code = (*get) (sym)->code;
400 if (code)
401 {
402 location loc = (*get) (sym)->location;
403 /* Filename, lineno,
404 Symbol-name, Symbol-number,
405 code, optional typename. */
406 fprintf (out, "%s[", sep);
407 sep = ",\n";
408 escaped_output (out, loc.start.file);
409 fprintf (out, ", %d, ", loc.start.line);
410 escaped_output (out, sym->tag);
411 fprintf (out, ", %d, [[%s]]", sym->number, code);
412 if (sym->type_name)
413 fprintf (out, ", [[%s]]", sym->type_name);
414 fputc (']', out);
415 }
416 }
417 fputs ("])\n\n", out);
418 }
419
420
421 static void
422 prepare_actions (void)
423 {
424 /* Figure out the actions for the specified state, indexed by
425 lookahead token type. */
426
427 muscle_insert_rule_number_table ("defact", yydefact,
428 yydefact[0], 1, nstates);
429
430 /* Figure out what to do after reducing with each rule, depending on
431 the saved state from before the beginning of parsing the data
432 that matched this rule. */
433 muscle_insert_state_number_table ("defgoto", yydefgoto,
434 yydefgoto[0], 1, nsyms - ntokens);
435
436
437 /* Output PACT. */
438 muscle_insert_base_table ("pact", base,
439 base[0], 1, nstates);
440 MUSCLE_INSERT_INT ("pact_ninf", base_ninf);
441
442 /* Output PGOTO. */
443 muscle_insert_base_table ("pgoto", base,
444 base[nstates], nstates + 1, nvectors);
445
446 muscle_insert_base_table ("table", table,
447 table[0], 1, high + 1);
448 MUSCLE_INSERT_INT ("table_ninf", table_ninf);
449
450 muscle_insert_base_table ("check", check,
451 check[0], 1, high + 1);
452
453 /* GLR parsing slightly modifies YYTABLE and YYCHECK (and thus
454 YYPACT) so that in states with unresolved conflicts, the default
455 reduction is not used in the conflicted entries, so that there is
456 a place to put a conflict pointer.
457
458 This means that YYCONFLP and YYCONFL are nonsense for a non-GLR
459 parser, so we could avoid accidents by not writing them out in
460 that case. Nevertheless, it seems even better to be able to use
461 the GLR skeletons even without the non-deterministic tables. */
462 muscle_insert_unsigned_int_table ("conflict_list_heads", conflict_table,
463 conflict_table[0], 1, high + 1);
464 muscle_insert_unsigned_int_table ("conflicting_rules", conflict_list,
465 0, 1, conflict_list_cnt);
466 }
467
468 \f
469 /*---------------------------.
470 | Call the skeleton parser. |
471 `---------------------------*/
472
473 static void
474 output_skeleton (void)
475 {
476 FILE *in;
477 FILE *out;
478 int filter_fd[2];
479 char const *argv[10];
480 pid_t pid;
481
482 /* Compute the names of the package data dir and skeleton files. */
483 char const m4sugar[] = "m4sugar/m4sugar.m4";
484 char const m4bison[] = "bison.m4";
485 char *full_m4sugar;
486 char *full_m4bison;
487 char *full_skeleton;
488 char const *p;
489 char const *m4 = (p = getenv ("M4")) ? p : M4;
490 char const *pkgdatadir = compute_pkgdatadir ();
491 size_t skeleton_size = strlen (skeleton) + 1;
492 size_t pkgdatadirlen = strlen (pkgdatadir);
493 while (pkgdatadirlen && pkgdatadir[pkgdatadirlen - 1] == '/')
494 pkgdatadirlen--;
495 full_skeleton = xmalloc (pkgdatadirlen + 1
496 + (skeleton_size < sizeof m4sugar
497 ? sizeof m4sugar : skeleton_size));
498 strncpy (full_skeleton, pkgdatadir, pkgdatadirlen);
499 full_skeleton[pkgdatadirlen] = '/';
500 strcpy (full_skeleton + pkgdatadirlen + 1, m4sugar);
501 full_m4sugar = xstrdup (full_skeleton);
502 strcpy (full_skeleton + pkgdatadirlen + 1, m4bison);
503 full_m4bison = xstrdup (full_skeleton);
504 if (strchr (skeleton, '/'))
505 strcpy (full_skeleton, skeleton);
506 else
507 strcpy (full_skeleton + pkgdatadirlen + 1, skeleton);
508
509 /* Test whether m4sugar.m4 is readable, to check for proper
510 installation. A faulty installation can cause deadlock, so a
511 cheap sanity check is worthwhile. */
512 xfclose (xfopen (full_m4sugar, "r"));
513
514 /* Create an m4 subprocess connected to us via two pipes. */
515
516 if (trace_flag & trace_tools)
517 fprintf (stderr, "running: %s %s - %s %s\n",
518 m4, full_m4sugar, full_m4bison, full_skeleton);
519
520 /* Some future version of GNU M4 (most likely 1.6) may treat the -dV in a
521 position-dependent manner. Keep it as the first argument so that all
522 files are traced.
523
524 See the thread starting at
525 <http://lists.gnu.org/archive/html/bug-bison/2008-07/msg00000.html>
526 for details. */
527 {
528 int i = 0;
529 argv[i++] = m4;
530
531 /* When POSIXLY_CORRECT is set, GNU M4 1.6 and later disable GNU
532 extensions, which Bison's skeletons depend on. With older M4,
533 it has no effect. M4 1.4.12 added a -g/--gnu command-line
534 option to make it explicit that a program wants GNU M4
535 extensions even when POSIXLY_CORRECT is set.
536
537 See the thread starting at
538 <http://lists.gnu.org/archive/html/bug-bison/2008-07/msg00000.html>
539 for details. */
540 if (*M4_GNU_OPTION)
541 argv[i++] = M4_GNU_OPTION;
542
543 argv[i++] = "-I";
544 argv[i++] = pkgdatadir;
545 if (trace_flag & trace_m4)
546 argv[i++] = "-dV";
547 argv[i++] = full_m4sugar;
548 argv[i++] = "-";
549 argv[i++] = full_m4bison;
550 argv[i++] = full_skeleton;
551 argv[i++] = NULL;
552 assert (i <= ARRAY_CARDINALITY (argv));
553 }
554
555 /* The ugly cast is because gnulib gets the const-ness wrong. */
556 pid = create_pipe_bidi ("m4", m4, (char **)(void*)argv, false, true,
557 true, filter_fd);
558 free (full_m4sugar);
559 free (full_m4bison);
560 free (full_skeleton);
561
562 out = fdopen (filter_fd[1], "w");
563 if (! out)
564 error (EXIT_FAILURE, get_errno (),
565 "fdopen");
566
567 /* Output the definitions of all the muscles. */
568 fputs ("m4_init()\n", out);
569
570 user_actions_output (out);
571 merger_output (out);
572 token_definitions_output (out);
573 symbol_code_props_output (out, "destructors", &symbol_destructor_get);
574 symbol_code_props_output (out, "printers", &symbol_printer_get);
575
576 muscles_m4_output (out);
577 xfclose (out);
578
579 /* Read and process m4's output. */
580 timevar_push (TV_M4);
581 in = fdopen (filter_fd[0], "r");
582 if (! in)
583 error (EXIT_FAILURE, get_errno (),
584 "fdopen");
585 scan_skel (in);
586 /* scan_skel should have read all of M4's output. Otherwise, when we
587 close the pipe, we risk letting M4 report a broken-pipe to the
588 Bison user. */
589 aver (feof (in));
590 xfclose (in);
591 wait_subprocess (pid, "m4", false, false, true, true, NULL);
592 timevar_pop (TV_M4);
593 }
594
595 static void
596 prepare (void)
597 {
598 /* BISON_USE_PUSH_FOR_PULL is for the test suite and should not be documented
599 for the user. */
600 char const *use_push_for_pull_env = getenv ("BISON_USE_PUSH_FOR_PULL");
601 bool use_push_for_pull_flag = false;
602 if (use_push_for_pull_env != NULL
603 && use_push_for_pull_env[0] != '\0'
604 && 0 != strcmp (use_push_for_pull_env, "0"))
605 use_push_for_pull_flag = true;
606
607 /* Flags. */
608 MUSCLE_INSERT_BOOL ("debug_flag", debug_flag);
609 MUSCLE_INSERT_BOOL ("defines_flag", defines_flag);
610 MUSCLE_INSERT_BOOL ("error_verbose_flag", error_verbose);
611 MUSCLE_INSERT_BOOL ("glr_flag", glr_parser);
612 MUSCLE_INSERT_BOOL ("locations_flag", locations_flag);
613 MUSCLE_INSERT_BOOL ("nondeterministic_flag", nondeterministic_parser);
614 MUSCLE_INSERT_BOOL ("synclines_flag", !no_lines_flag);
615 MUSCLE_INSERT_BOOL ("tag_seen_flag", tag_seen);
616 MUSCLE_INSERT_BOOL ("use_push_for_pull_flag", use_push_for_pull_flag);
617 MUSCLE_INSERT_BOOL ("yacc_flag", yacc_flag);
618
619 /* File names. */
620 if (spec_name_prefix)
621 MUSCLE_INSERT_STRING ("prefix", spec_name_prefix);
622
623 MUSCLE_INSERT_STRING ("file_name_all_but_ext", all_but_ext);
624
625 #define DEFINE(Name) MUSCLE_INSERT_STRING (#Name, Name ? Name : "")
626 DEFINE (dir_prefix);
627 DEFINE (parser_file_name);
628 DEFINE (spec_defines_file);
629 DEFINE (spec_file_prefix);
630 DEFINE (spec_graph_file);
631 DEFINE (spec_name_prefix);
632 DEFINE (spec_outfile);
633 DEFINE (spec_verbose_file);
634 #undef DEFINE
635
636 /* Find the right skeleton file, and add muscles about the skeletons. */
637 if (skeleton)
638 MUSCLE_INSERT_C_STRING ("skeleton", skeleton);
639 else
640 skeleton = language->skeleton;
641
642 /* About the skeletons. */
643 {
644 /* b4_pkgdatadir is used inside m4_include in the skeletons, so digraphs
645 would never be expanded. Hopefully no one has M4-special characters in
646 his Bison installation path. */
647 MUSCLE_INSERT_STRING_RAW ("pkgdatadir", compute_pkgdatadir ());
648 }
649 }
650
651
652 /*----------------------------------------------------------.
653 | Output the parsing tables and the parser code to ftable. |
654 `----------------------------------------------------------*/
655
656 void
657 output (void)
658 {
659 obstack_init (&format_obstack);
660
661 prepare_symbols ();
662 prepare_rules ();
663 prepare_states ();
664 prepare_actions ();
665
666 prepare ();
667
668 /* Process the selected skeleton file. */
669 output_skeleton ();
670
671 obstack_free (&format_obstack, NULL);
672 }
673
674 char const *
675 compute_pkgdatadir (void)
676 {
677 char const *pkgdatadir = getenv ("BISON_PKGDATADIR");
678 return pkgdatadir ? pkgdatadir : PKGDATADIR;
679 }