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1 # Bison Regressions. -*- Autotest -*-
2
3 # Copyright (C) 2001-2012 Free Software Foundation, Inc.
4
5 # This program is free software: you can redistribute it and/or modify
6 # it under the terms of the GNU General Public License as published by
7 # the Free Software Foundation, either version 3 of the License, or
8 # (at your option) any later version.
9 #
10 # This program is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 # GNU General Public License for more details.
14 #
15 # You should have received a copy of the GNU General Public License
16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
17
18 AT_BANNER([[Regression tests.]])
19
20
21 ## ------------------ ##
22 ## Trivial grammars. ##
23 ## ------------------ ##
24
25 AT_SETUP([Trivial grammars])
26
27 AT_DATA_GRAMMAR([input.y],
28 [[%{
29 void yyerror (char const *);
30 int yylex (void);
31 #define YYSTYPE int *
32 %}
33
34 %error-verbose
35
36 %%
37
38 program: 'x';
39 ]])
40
41 AT_BISON_CHECK([-o input.c input.y])
42 AT_COMPILE([input.o], [-c input.c])
43 AT_COMPILE([input.o], [-DYYDEBUG -c input.c])
44
45 AT_CLEANUP
46
47
48
49 ## ----------------- ##
50 ## YYSTYPE typedef. ##
51 ## ----------------- ##
52
53 AT_SETUP([YYSTYPE typedef])
54
55 AT_DATA_GRAMMAR([input.y],
56 [[%{
57 void yyerror (char const *);
58 int yylex (void);
59 typedef union { char const *val; } YYSTYPE;
60 %}
61
62 %type <val> program
63
64 %%
65
66 program: { $$ = ""; };
67 ]])
68
69 AT_BISON_CHECK([-o input.c input.y])
70 AT_COMPILE([input.o], [-c input.c])
71
72 AT_CLEANUP
73
74
75
76 ## ------------------------------------- ##
77 ## Early token definitions with --yacc. ##
78 ## ------------------------------------- ##
79
80
81 AT_SETUP([Early token definitions with --yacc])
82
83 # Found in GCJ: they expect the tokens to be defined before the user
84 # prologue, so that they can use the token definitions in it.
85
86 AT_DATA_GRAMMAR([input.y],
87 [[%{
88 void yyerror (const char *s);
89 int yylex (void);
90 %}
91
92 %union
93 {
94 int val;
95 };
96 %{
97 #ifndef MY_TOKEN
98 # error "MY_TOKEN not defined."
99 #endif
100 %}
101 %token MY_TOKEN
102 %%
103 exp: MY_TOKEN;
104 %%
105 ]])
106
107 AT_BISON_CHECK([-y -o input.c input.y])
108 AT_COMPILE([input.o], [-c input.c])
109
110 AT_CLEANUP
111
112
113
114 ## ---------------------------------------- ##
115 ## Early token definitions without --yacc. ##
116 ## ---------------------------------------- ##
117
118
119 AT_SETUP([Early token definitions without --yacc])
120
121 # Found in GCJ: they expect the tokens to be defined before the user
122 # prologue, so that they can use the token definitions in it.
123
124 AT_DATA_GRAMMAR([input.y],
125 [[%{
126 #include <stdio.h>
127 void yyerror (const char *s);
128 int yylex (void);
129 void print_my_token (void);
130 %}
131
132 %union
133 {
134 int val;
135 };
136 %{
137 void
138 print_my_token (void)
139 {
140 enum yytokentype my_token = MY_TOKEN;
141 printf ("%d\n", my_token);
142 }
143 %}
144 %token MY_TOKEN
145 %%
146 exp: MY_TOKEN;
147 %%
148 ]])
149
150 AT_BISON_CHECK([-o input.c input.y])
151 AT_COMPILE([input.o], [-c input.c])
152
153 AT_CLEANUP
154
155
156
157 ## ---------------- ##
158 ## Braces parsing. ##
159 ## ---------------- ##
160
161
162 AT_SETUP([Braces parsing])
163
164 AT_DATA([input.y],
165 [[/* Bison used to swallow the character after '}'. */
166
167 %%
168 exp: { tests = {{{{{{{{{{}}}}}}}}}}; };
169 %%
170 ]])
171
172 AT_BISON_CHECK([-v -o input.c input.y])
173
174 AT_CHECK([grep 'tests = {{{{{{{{{{}}}}}}}}}};' input.c], 0, [ignore])
175
176 AT_CLEANUP
177
178
179 ## ------------------ ##
180 ## Duplicate string. ##
181 ## ------------------ ##
182
183
184 AT_SETUP([Duplicate string])
185
186 AT_DATA([input.y],
187 [[/* 'Bison -v' used to dump core when two tokens are defined with the same
188 string, as LE and GE below. */
189
190 %token NUM
191 %token LE "<="
192 %token GE "<="
193
194 %%
195 exp: '(' exp ')' | NUM ;
196 %%
197 ]])
198
199 AT_BISON_CHECK([-v -o input.c input.y], 0, [],
200 [[input.y:6.8-14: warning: symbol "<=" used more than once as a literal string
201 ]])
202
203 AT_CLEANUP
204
205
206 ## ------------------- ##
207 ## Rule Line Numbers. ##
208 ## ------------------- ##
209
210 AT_SETUP([Rule Line Numbers])
211
212 AT_KEYWORDS([report])
213
214 AT_DATA([input.y],
215 [[%%
216 expr:
217 'a'
218
219 {
220
221 }
222
223 'b'
224
225 {
226
227 }
228
229 |
230
231
232 {
233
234
235 }
236
237 'c'
238
239 {
240
241 };
242 ]])
243
244 AT_BISON_CHECK([-o input.c -v input.y])
245
246 # Check the contents of the report.
247 AT_CHECK([cat input.output], [],
248 [[Grammar
249
250 0 $accept: expr $end
251
252 1 $@1: /* empty */
253
254 2 expr: 'a' $@1 'b'
255
256 3 $@2: /* empty */
257
258 4 expr: $@2 'c'
259
260
261 Terminals, with rules where they appear
262
263 $end (0) 0
264 'a' (97) 2
265 'b' (98) 2
266 'c' (99) 4
267 error (256)
268
269
270 Nonterminals, with rules where they appear
271
272 $accept (6)
273 on left: 0
274 expr (7)
275 on left: 2 4, on right: 0
276 $@1 (8)
277 on left: 1, on right: 2
278 $@2 (9)
279 on left: 3, on right: 4
280
281
282 state 0
283
284 0 $accept: . expr $end
285
286 'a' shift, and go to state 1
287
288 $default reduce using rule 3 ($@2)
289
290 expr go to state 2
291 $@2 go to state 3
292
293
294 state 1
295
296 2 expr: 'a' . $@1 'b'
297
298 $default reduce using rule 1 ($@1)
299
300 $@1 go to state 4
301
302
303 state 2
304
305 0 $accept: expr . $end
306
307 $end shift, and go to state 5
308
309
310 state 3
311
312 4 expr: $@2 . 'c'
313
314 'c' shift, and go to state 6
315
316
317 state 4
318
319 2 expr: 'a' $@1 . 'b'
320
321 'b' shift, and go to state 7
322
323
324 state 5
325
326 0 $accept: expr $end .
327
328 $default accept
329
330
331 state 6
332
333 4 expr: $@2 'c' .
334
335 $default reduce using rule 4 (expr)
336
337
338 state 7
339
340 2 expr: 'a' $@1 'b' .
341
342 $default reduce using rule 2 (expr)
343 ]])
344
345 AT_CLEANUP
346
347
348
349 ## ---------------------- ##
350 ## Mixing %token styles. ##
351 ## ---------------------- ##
352
353
354 AT_SETUP([Mixing %token styles])
355
356 # Taken from the documentation.
357 AT_DATA([input.y],
358 [[%token <operator> OR "||"
359 %token <operator> LE 134 "<="
360 %left OR "<="
361 %%
362 exp: ;
363 %%
364 ]])
365
366 AT_BISON_CHECK([-v -o input.c input.y])
367
368 AT_CLEANUP
369
370
371
372 ## ---------------- ##
373 ## Invalid inputs. ##
374 ## ---------------- ##
375
376
377 AT_SETUP([Invalid inputs])
378
379 AT_DATA([input.y],
380 [[%%
381 ?
382 default: 'a' }
383 %&
384 %a-does-not-exist
385 %-
386 %{
387 ]])
388
389 AT_BISON_CHECK([input.y], [1], [],
390 [[input.y:2.1: invalid character: '?'
391 input.y:3.14: invalid character: '}'
392 input.y:4.1: invalid character: '%'
393 input.y:4.2: invalid character: '&'
394 input.y:5.1-17: invalid directive: '%a-does-not-exist'
395 input.y:6.1: invalid character: '%'
396 input.y:6.2: invalid character: '-'
397 input.y:7.1-8.0: missing '%}' at end of file
398 input.y:7.1-8.0: syntax error, unexpected %{...%}
399 ]])
400
401 AT_CLEANUP
402
403
404 AT_SETUP([Invalid inputs with {}])
405
406 AT_DATA([input.y],
407 [[
408 %destructor
409 %initial-action
410 %lex-param
411 %parse-param
412 %printer
413 %union
414 ]])
415
416 AT_BISON_CHECK([input.y], [1], [],
417 [[input.y:3.1-15: syntax error, unexpected %initial-action, expecting {...}
418 ]])
419
420 AT_CLEANUP
421
422
423
424 ## ------------------- ##
425 ## Token definitions. ##
426 ## ------------------- ##
427
428
429 AT_SETUP([Token definitions])
430
431 # Bison managed, when fed with '%token 'f' "f"' to #define 'f'!
432 AT_DATA_GRAMMAR([input.y],
433 [%{
434 #include <stdlib.h>
435 #include <stdio.h>
436 void yyerror (const char *s);
437 int yylex (void);
438 %}
439 [%error-verbose
440 %token MYEOF 0 "end of file"
441 %token 'a' "a"
442 %token B_TOKEN "b"
443 %token C_TOKEN 'c'
444 %token 'd' D_TOKEN
445 %token SPECIAL "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!"
446 %token SPECIAL "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!"
447 %%
448 exp: "a" "\\\'\?\"\a\b\f\n\r\t\v\001\201\x001\x000081??!";
449 %%
450 void
451 yyerror (char const *s)
452 {
453 fprintf (stderr, "%s\n", s);
454 }
455
456 int
457 yylex (void)
458 {
459 static int called;
460 if (called++)
461 abort ();
462 return SPECIAL;
463 }
464
465 int
466 main (void)
467 {
468 return yyparse ();
469 }
470 ]])
471
472 # Checking the warning message guarantees that the trigraph "??!" isn't
473 # unnecessarily escaped here even though it would need to be if encoded in a
474 # C-string literal. Also notice that unnecessary escaping, such as "\?", from
475 # the user specification is eliminated.
476 AT_BISON_CHECK([-o input.c input.y], [[0]], [[]],
477 [[input.y:22.8-14: warning: symbol SPECIAL redeclared
478 input.y:22.8-63: warning: symbol "\\'?\"\a\b\f\n\r\t\v\001\201\001\201??!" used more than once as a literal string
479 ]])
480 AT_COMPILE([input])
481
482 # Checking the error message here guarantees that yytname, which does contain
483 # C-string literals, does have the trigraph escaped correctly. Thus, the
484 # symbol name reported by the parser is exactly the same as that reported by
485 # Bison itself.
486 AT_DATA([experr],
487 [[syntax error, unexpected "\\'?\"\a\b\f\n\r\t\v\001\201\001\201??!", expecting a
488 ]])
489 AT_PARSER_CHECK([./input], 1, [], [experr])
490 AT_CLEANUP
491
492
493
494 ## -------------------- ##
495 ## Characters Escapes. ##
496 ## -------------------- ##
497
498
499 AT_SETUP([Characters Escapes])
500
501 AT_DATA_GRAMMAR([input.y],
502 [%{
503 void yyerror (const char *s);
504 int yylex (void);
505 %}
506 [%%
507 exp:
508 '\'' "\'"
509 | '\"' "\""
510 | '"' "'"
511 ;
512 ]])
513 # Pacify font-lock-mode: "
514
515 AT_BISON_CHECK([-o input.c input.y])
516 AT_COMPILE([input.o], [-c input.c])
517 AT_CLEANUP
518
519
520
521 ## -------------- ##
522 ## Web2c Report. ##
523 ## -------------- ##
524
525 # The generation of the reduction was once wrong in Bison, and made it
526 # miss some reductions. In the following test case, the reduction on
527 # 'undef_id_tok' in state 1 was missing. This is stripped down from
528 # the actual web2c.y.
529
530 AT_SETUP([Web2c Report])
531
532 AT_KEYWORDS([report])
533
534 AT_DATA([input.y],
535 [[%token undef_id_tok const_id_tok
536
537 %start CONST_DEC_PART
538 \f
539 %%
540 CONST_DEC_PART:
541 CONST_DEC_LIST
542 ;
543
544 CONST_DEC_LIST:
545 CONST_DEC
546 | CONST_DEC_LIST CONST_DEC
547 ;
548
549 CONST_DEC:
550 { } undef_id_tok '=' const_id_tok ';'
551 ;
552 %%
553 ]])
554
555 AT_BISON_CHECK([-v input.y])
556 AT_CHECK([cat input.output], 0,
557 [[Grammar
558
559 0 $accept: CONST_DEC_PART $end
560
561 1 CONST_DEC_PART: CONST_DEC_LIST
562
563 2 CONST_DEC_LIST: CONST_DEC
564 3 | CONST_DEC_LIST CONST_DEC
565
566 4 $@1: /* empty */
567
568 5 CONST_DEC: $@1 undef_id_tok '=' const_id_tok ';'
569
570
571 Terminals, with rules where they appear
572
573 $end (0) 0
574 ';' (59) 5
575 '=' (61) 5
576 error (256)
577 undef_id_tok (258) 5
578 const_id_tok (259) 5
579
580
581 Nonterminals, with rules where they appear
582
583 $accept (7)
584 on left: 0
585 CONST_DEC_PART (8)
586 on left: 1, on right: 0
587 CONST_DEC_LIST (9)
588 on left: 2 3, on right: 1 3
589 CONST_DEC (10)
590 on left: 5, on right: 2 3
591 $@1 (11)
592 on left: 4, on right: 5
593
594
595 state 0
596
597 0 $accept: . CONST_DEC_PART $end
598
599 $default reduce using rule 4 ($@1)
600
601 CONST_DEC_PART go to state 1
602 CONST_DEC_LIST go to state 2
603 CONST_DEC go to state 3
604 $@1 go to state 4
605
606
607 state 1
608
609 0 $accept: CONST_DEC_PART . $end
610
611 $end shift, and go to state 5
612
613
614 state 2
615
616 1 CONST_DEC_PART: CONST_DEC_LIST .
617 3 CONST_DEC_LIST: CONST_DEC_LIST . CONST_DEC
618
619 undef_id_tok reduce using rule 4 ($@1)
620 $default reduce using rule 1 (CONST_DEC_PART)
621
622 CONST_DEC go to state 6
623 $@1 go to state 4
624
625
626 state 3
627
628 2 CONST_DEC_LIST: CONST_DEC .
629
630 $default reduce using rule 2 (CONST_DEC_LIST)
631
632
633 state 4
634
635 5 CONST_DEC: $@1 . undef_id_tok '=' const_id_tok ';'
636
637 undef_id_tok shift, and go to state 7
638
639
640 state 5
641
642 0 $accept: CONST_DEC_PART $end .
643
644 $default accept
645
646
647 state 6
648
649 3 CONST_DEC_LIST: CONST_DEC_LIST CONST_DEC .
650
651 $default reduce using rule 3 (CONST_DEC_LIST)
652
653
654 state 7
655
656 5 CONST_DEC: $@1 undef_id_tok . '=' const_id_tok ';'
657
658 '=' shift, and go to state 8
659
660
661 state 8
662
663 5 CONST_DEC: $@1 undef_id_tok '=' . const_id_tok ';'
664
665 const_id_tok shift, and go to state 9
666
667
668 state 9
669
670 5 CONST_DEC: $@1 undef_id_tok '=' const_id_tok . ';'
671
672 ';' shift, and go to state 10
673
674
675 state 10
676
677 5 CONST_DEC: $@1 undef_id_tok '=' const_id_tok ';' .
678
679 $default reduce using rule 5 (CONST_DEC)
680 ]])
681
682 AT_CLEANUP
683
684
685 ## --------------- ##
686 ## Web2c Actions. ##
687 ## --------------- ##
688
689 # The generation of the mapping 'state -> action' was once wrong in
690 # extremely specific situations. web2c.y exhibits this situation.
691 # Below is a stripped version of the grammar. It looks like one can
692 # simplify it further, but just don't: it is tuned to exhibit a bug,
693 # which disapears when applying sane grammar transformations.
694 #
695 # It used to be wrong on yydefact only:
696 #
697 # static const yytype_uint8 yydefact[] =
698 # {
699 # - 2, 0, 1, 0, 0, 2, 3, 2, 5, 4,
700 # + 2, 0, 1, 0, 0, 0, 3, 2, 5, 4,
701 # 0, 0
702 # };
703 #
704 # but let's check all the tables.
705
706
707 AT_SETUP([Web2c Actions])
708
709 AT_KEYWORDS([report])
710
711 AT_DATA([input.y],
712 [[%%
713 statement: struct_stat;
714 struct_stat: /* empty. */ | if else;
715 if: "if" "const" "then" statement;
716 else: "else" statement;
717 %%
718 ]])
719
720 AT_BISON_CHECK([-v -o input.c input.y])
721
722 # Check only the tables.
723 [sed -n 's/ *$//;/^static const.*\[\] =/,/^}/p' input.c >tables.c]
724
725 AT_CHECK([[cat tables.c]], 0,
726 [[static const yytype_uint8 yytranslate[] =
727 {
728 0, 2, 2, 2, 2, 2, 2, 2, 2, 2,
729 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
730 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
731 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
732 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
733 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
734 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
735 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
736 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
737 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
738 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
739 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
740 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
741 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
742 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
743 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
744 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
745 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
746 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
747 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
748 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
749 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
750 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
751 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
752 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
753 2, 2, 2, 2, 2, 2, 1, 2, 3, 4,
754 5, 6
755 };
756 static const yytype_uint8 yyrline[] =
757 {
758 0, 2, 2, 3, 3, 4, 5
759 };
760 static const char *const yytname[] =
761 {
762 "$end", "error", "$undefined", "\"if\"", "\"const\"", "\"then\"",
763 "\"else\"", "$accept", "statement", "struct_stat", "if", "else", YY_NULL
764 };
765 static const yytype_uint16 yytoknum[] =
766 {
767 0, 256, 257, 258, 259, 260, 261
768 };
769 static const yytype_int8 yypact[] =
770 {
771 -2, -1, 4, -8, 0, 2, -8, -2, -8, -2,
772 -8, -8
773 };
774 static const yytype_uint8 yydefact[] =
775 {
776 3, 0, 0, 2, 0, 0, 1, 3, 4, 3,
777 6, 5
778 };
779 static const yytype_int8 yypgoto[] =
780 {
781 -8, -7, -8, -8, -8
782 };
783 static const yytype_int8 yydefgoto[] =
784 {
785 -1, 2, 3, 4, 8
786 };
787 static const yytype_uint8 yytable[] =
788 {
789 10, 1, 11, 5, 6, 0, 7, 9
790 };
791 static const yytype_int8 yycheck[] =
792 {
793 7, 3, 9, 4, 0, -1, 6, 5
794 };
795 static const yytype_uint8 yystos[] =
796 {
797 0, 3, 8, 9, 10, 4, 0, 6, 11, 5,
798 8, 8
799 };
800 static const yytype_uint8 yyr1[] =
801 {
802 0, 7, 8, 9, 9, 10, 11
803 };
804 static const yytype_uint8 yyr2[] =
805 {
806 0, 2, 1, 0, 2, 4, 2
807 };
808 ]])
809
810 AT_CLEANUP
811
812
813 ## ------------------------- ##
814 ## yycheck Bound Violation. ##
815 ## ------------------------- ##
816
817
818 # _AT_DATA_DANCER_Y(BISON-OPTIONS)
819 # --------------------------------
820 # The following grammar, taken from Andrew Suffield's GPL'd implementation
821 # of DGMTP, the Dancer Generic Message Transport Protocol, used to violate
822 # yycheck's bounds where issuing a verbose error message. Keep this test
823 # so that possible bound checking compilers could check all the skeletons.
824 m4_define([_AT_DATA_DANCER_Y],
825 [AT_DATA_GRAMMAR([dancer.y],
826 [%{
827 static int yylex (AT_LALR1_CC_IF([int *], [void]));
828 AT_LALR1_CC_IF([#include <cstdlib>],
829 [#include <stdlib.h>
830 #include <stdio.h>
831 static void yyerror (const char *);])
832 %}
833 $1
834 %token ARROW INVALID NUMBER STRING DATA
835 %defines
836 %verbose
837 %error-verbose
838 /* Grammar follows */
839 %%
840 line: header body
841 ;
842
843 header: '<' from ARROW to '>' type ':'
844 | '<' ARROW to '>' type ':'
845 | ARROW to type ':'
846 | type ':'
847 | '<' '>'
848 ;
849
850 from: DATA
851 | STRING
852 | INVALID
853 ;
854
855 to: DATA
856 | STRING
857 | INVALID
858 ;
859
860 type: DATA
861 | STRING
862 | INVALID
863 ;
864
865 body: /* empty */
866 | body member
867 ;
868
869 member: STRING
870 | DATA
871 | '+' NUMBER
872 | '-' NUMBER
873 | NUMBER
874 | INVALID
875 ;
876 %%
877 AT_LALR1_CC_IF(
878 [/* A C++ error reporting function. */
879 void
880 yy::parser::error (const std::string& m)
881 {
882 std::cerr << m << std::endl;
883 }
884
885 int
886 yyparse ()
887 {
888 yy::parser parser;
889 #if YYDEBUG
890 parser.set_debug_level (YYDEBUG);
891 #endif
892 return parser.parse ();
893 }
894 ],
895 [static void
896 yyerror (const char *s)
897 {
898 fprintf (stderr, "%s\n", s);
899 }])
900
901 static int
902 yylex (AT_LALR1_CC_IF([int *lval], [void]))
903 [{
904 static int const tokens[] =
905 {
906 ':', -1
907 };
908 static size_t toknum;
909 ]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[
910 if (! (toknum < sizeof tokens / sizeof *tokens))
911 abort ();
912 return tokens[toknum++];
913 }]
914
915 int
916 main (void)
917 {
918 return yyparse ();
919 }
920 ])
921 ])# _AT_DATA_DANCER_Y
922
923
924 # AT_CHECK_DANCER(BISON-OPTIONS)
925 # ------------------------------
926 # Generate the grammar, compile it, run it.
927 m4_define([AT_CHECK_DANCER],
928 [AT_SETUP([Dancer $1])
929 AT_BISON_OPTION_PUSHDEFS([$1])
930 _AT_DATA_DANCER_Y([$1])
931 AT_BISON_CHECK([-o dancer.c dancer.y])
932 AT_FULL_COMPILE([dancer])
933 AT_PARSER_CHECK([./dancer], 1, [],
934 [syntax error, unexpected ':'
935 ])
936 AT_BISON_OPTION_POPDEFS
937 AT_CLEANUP
938 ])
939
940 AT_CHECK_DANCER()
941 AT_CHECK_DANCER([%glr-parser])
942 AT_CHECK_DANCER([%skeleton "lalr1.cc"])
943
944
945 ## ------------------------------------------ ##
946 ## Diagnostic that expects two alternatives. ##
947 ## ------------------------------------------ ##
948
949
950 # _AT_DATA_EXPECT2_Y(BISON-OPTIONS)
951 # --------------------------------
952 m4_define([_AT_DATA_EXPECT2_Y],
953 [AT_DATA_GRAMMAR([expect2.y],
954 [%{
955 static int yylex (AT_LALR1_CC_IF([int *], [void]));
956 AT_LALR1_CC_IF([#include <cstdlib>],
957 [#include <stdio.h>
958 #include <stdlib.h>
959 static void yyerror (const char *);])
960 %}
961 $1
962 %defines
963 %error-verbose
964 %token A 1000
965 %token B
966
967 %%
968 program: /* empty */
969 | program e ';'
970 | program error ';';
971
972 e: e '+' t | t;
973 t: A | B;
974
975 %%
976 AT_LALR1_CC_IF(
977 [/* A C++ error reporting function. */
978 void
979 yy::parser::error (const std::string& m)
980 {
981 std::cerr << m << std::endl;
982 }
983
984 int
985 yyparse ()
986 {
987 yy::parser parser;
988 return parser.parse ();
989 }
990 ],
991 [static void
992 yyerror (const char *s)
993 {
994 fprintf (stderr, "%s\n", s);
995 }])
996
997 static int
998 yylex (AT_LALR1_CC_IF([int *lval], [void]))
999 [{
1000 static int const tokens[] =
1001 {
1002 1000, '+', '+', -1
1003 };
1004 static size_t toknum;
1005 ]AT_LALR1_CC_IF([*lval = 0; /* Pacify GCC. */])[
1006 if (! (toknum < sizeof tokens / sizeof *tokens))
1007 abort ();
1008 return tokens[toknum++];
1009 }]
1010
1011 int
1012 main (void)
1013 {
1014 return yyparse ();
1015 }
1016 ])
1017 ])# _AT_DATA_EXPECT2_Y
1018
1019
1020 # AT_CHECK_EXPECT2(BISON-OPTIONS)
1021 # ------------------------------
1022 # Generate the grammar, compile it, run it.
1023 m4_define([AT_CHECK_EXPECT2],
1024 [AT_SETUP([Expecting two tokens $1])
1025 AT_BISON_OPTION_PUSHDEFS([$1])
1026 _AT_DATA_EXPECT2_Y([$1])
1027 AT_BISON_CHECK([-o expect2.c expect2.y])
1028 AT_FULL_COMPILE([expect2])
1029 AT_PARSER_CHECK([./expect2], 1, [],
1030 [syntax error, unexpected '+', expecting A or B
1031 ])
1032 AT_BISON_OPTION_POPDEFS
1033 AT_CLEANUP
1034 ])
1035
1036 AT_CHECK_EXPECT2()
1037 AT_CHECK_EXPECT2([%glr-parser])
1038 AT_CHECK_EXPECT2([%skeleton "lalr1.cc"])
1039
1040
1041
1042 ## --------------------------------------------- ##
1043 ## Braced code in declaration in rules section. ##
1044 ## --------------------------------------------- ##
1045
1046 AT_SETUP([Braced code in declaration in rules section])
1047
1048 # Bison once mistook braced code in a declaration in the rules section to be a
1049 # rule action.
1050
1051 AT_DATA_GRAMMAR([input.y],
1052 [[%{
1053 #include <stdio.h>
1054 static void yyerror (char const *msg);
1055 static int yylex (void);
1056 %}
1057
1058 %error-verbose
1059
1060 %%
1061
1062 start:
1063 {
1064 printf ("Bison would once convert this action to a midrule because of the"
1065 " subsequent braced code.\n");
1066 }
1067 ;
1068
1069 %destructor { fprintf (stderr, "DESTRUCTOR\n"); } 'a';
1070 %printer { fprintf (yyoutput, "PRINTER"); } 'a';
1071
1072 %%
1073
1074 static void
1075 yyerror (char const *msg)
1076 {
1077 fprintf (stderr, "%s\n", msg);
1078 }
1079
1080 static int
1081 yylex (void)
1082 {
1083 return 'a';
1084 }
1085
1086 int
1087 main (void)
1088 {
1089 yydebug = 1;
1090 return !yyparse ();
1091 }
1092 ]])
1093
1094 AT_BISON_CHECK([-t -o input.c input.y])
1095 AT_COMPILE([input])
1096 AT_PARSER_CHECK([./input], 0,
1097 [[Bison would once convert this action to a midrule because of the subsequent braced code.
1098 ]],
1099 [[Starting parse
1100 Entering state 0
1101 Reducing stack by rule 1 (line 20):
1102 -> $$ = nterm start ()
1103 Stack now 0
1104 Entering state 1
1105 Reading a token: Next token is token 'a' (PRINTER)
1106 syntax error, unexpected 'a', expecting $end
1107 Error: popping nterm start ()
1108 Stack now 0
1109 Cleanup: discarding lookahead token 'a' (PRINTER)
1110 DESTRUCTOR
1111 Stack now 0
1112 ]])
1113
1114 AT_CLEANUP
1115
1116
1117
1118 ## --------------------------------- ##
1119 ## String alias declared after use. ##
1120 ## --------------------------------- ##
1121
1122 AT_SETUP([String alias declared after use])
1123
1124 # Bison once incorrectly asserted that the symbol number for either a token or
1125 # its alias was the highest symbol number so far at the point of the alias
1126 # declaration. That was true unless the declaration appeared after their first
1127 # uses and other tokens appeared in between.
1128
1129 AT_DATA([input.y],
1130 [[%%
1131 start: 'a' "A" 'b';
1132 %token 'a' "A";
1133 ]])
1134
1135 AT_BISON_CHECK([-t -o input.c input.y])
1136
1137 AT_CLEANUP
1138
1139
1140
1141 ## -------------------------------- ##
1142 ## Extra lookahead sets in report. ##
1143 ## -------------------------------- ##
1144
1145 AT_SETUP([[Extra lookahead sets in report]])
1146
1147 # Bison prints each reduction's lookahead set only next to the associated
1148 # state's one item that (1) is associated with the same rule as the reduction
1149 # and (2) has its dot at the end of its RHS. Previously, Bison also
1150 # erroneously printed the lookahead set next to all of the state's other items
1151 # associated with the same rule. This bug affected only the '.output' file and
1152 # not the generated parser source code.
1153
1154 AT_DATA([[input.y]],
1155 [[%%
1156 start: a | 'a' a 'a' ;
1157 a: 'a' ;
1158 ]])
1159
1160 AT_BISON_CHECK([[--report=all input.y]])
1161 AT_CHECK([[sed -n '/^state 1$/,/^state 2$/p' input.output]], [[0]],
1162 [[state 1
1163
1164 2 start: 'a' . a 'a'
1165 3 a: . 'a'
1166 3 | 'a' . [$end]
1167
1168 'a' shift, and go to state 4
1169
1170 $default reduce using rule 3 (a)
1171
1172 a go to state 5
1173
1174
1175 state 2
1176 ]])
1177
1178 AT_CLEANUP
1179
1180
1181
1182 ## ---------------------------------------- ##
1183 ## Token number in precedence declaration. ##
1184 ## ---------------------------------------- ##
1185
1186 AT_SETUP([[Token number in precedence declaration]])
1187
1188 # POSIX says token numbers can be declared in %left, %right, and %nonassoc, but
1189 # we lost this in Bison 1.50.
1190
1191 AT_DATA_GRAMMAR([input.y],
1192 [[%{
1193 #include <stdio.h>
1194 void yyerror (char const *);
1195 int yylex (void);
1196 %}
1197
1198 %error-verbose
1199 %right END 0
1200 %left TK1 1 TK2 2 "tok alias" 3
1201
1202 %%
1203
1204 start:
1205 TK1 sr_conflict "tok alias"
1206 | start %prec END
1207 ;
1208 sr_conflict:
1209 TK2
1210 | TK2 "tok alias"
1211 ;
1212
1213 %%
1214
1215 void
1216 yyerror (char const *msg)
1217 {
1218 fprintf (stderr, "%s\n", msg);
1219 }
1220
1221 int
1222 yylex (void)
1223 {
1224 static int const input[] = { 1, 2, 3, 0 };
1225 static int const *inputp = input;
1226 return *inputp++;
1227 }
1228
1229 int
1230 main (void)
1231 {
1232 return yyparse ();
1233 }
1234 ]])
1235
1236 AT_BISON_CHECK([[-o input.c input.y]], [[0]],,
1237 [[input.y:23.5-19: warning: rule useless in parser due to conflicts: start: start
1238 input.y:27.5-19: warning: rule useless in parser due to conflicts: sr_conflict: TK2 "tok alias"
1239 ]])
1240 AT_COMPILE([[input]])
1241 AT_PARSER_CHECK([[./input]])
1242
1243 AT_CLEANUP
1244
1245
1246
1247 ## --------------------------- ##
1248 ## parse-gram.y: LALR = IELR. ##
1249 ## --------------------------- ##
1250
1251 # If parse-gram.y's LALR and IELR parser tables ever begin to differ, we
1252 # need to fix parse-gram.y or start using IELR.
1253
1254 AT_SETUP([[parse-gram.y: LALR = IELR]])
1255
1256 # Avoid tests/bison's dark magic by processing a local copy of the
1257 # grammar. Avoid differences in synclines by telling bison that the
1258 # output files have the same name.
1259 [cp $abs_top_srcdir/src/parse-gram.y input.y]
1260 AT_BISON_CHECK([[-o input.c -Dlr.type=lalr input.y]])
1261 [mv input.c lalr.c]
1262 AT_CAPTURE_FILE([lalr.c])
1263 AT_BISON_CHECK([[-o input.c -Dlr.type=ielr input.y]])
1264 [mv input.c ielr.c]
1265 AT_CAPTURE_FILE([ielr.c])
1266 AT_CHECK([[diff lalr.c ielr.c]], [[0]])
1267
1268 AT_CLEANUP
1269
1270
1271
1272 ## -------------------------------------------- ##
1273 ## parse.error=verbose and YYSTACK_USE_ALLOCA. ##
1274 ## -------------------------------------------- ##
1275
1276 AT_SETUP([[parse.error=verbose and YYSTACK_USE_ALLOCA]])
1277
1278 AT_DATA_GRAMMAR([input.y],
1279 [[%code {
1280 #include <stdio.h>
1281 void yyerror (char const *);
1282 int yylex (void);
1283 #define YYSTACK_USE_ALLOCA 1
1284 }
1285
1286 %define parse.error verbose
1287
1288 %%
1289
1290 start: check syntax_error syntax_error ;
1291
1292 check:
1293 {
1294 if (128 < sizeof yymsgbuf)
1295 {
1296 fprintf (stderr,
1297 "The initial size of yymsgbuf in yyparse has increased\n"
1298 "since this test group was last updated. As a result,\n"
1299 "this test group may no longer manage to induce a\n"
1300 "reallocation of the syntax error message buffer.\n"
1301 "This test group must be adjusted to produce a longer\n"
1302 "error message.\n");
1303 YYABORT;
1304 }
1305 }
1306 ;
1307
1308 // Induce a syntax error message whose total length is more than
1309 // sizeof yymsgbuf in yyparse. Each token here is 64 bytes.
1310 syntax_error:
1311 "123456789112345678921234567893123456789412345678951234567896123A"
1312 | "123456789112345678921234567893123456789412345678951234567896123B"
1313 | error 'a' 'b' 'c'
1314 ;
1315
1316 %%
1317
1318 void
1319 yyerror (char const *msg)
1320 {
1321 fprintf (stderr, "%s\n", msg);
1322 }
1323
1324 int
1325 yylex (void)
1326 {
1327 /* Induce two syntax error messages (which requires full error
1328 recovery by shifting 3 tokens) in order to detect any loss of the
1329 reallocated buffer. */
1330 static char const *input = "abc";
1331 return *input++;
1332 }
1333
1334 int
1335 main (void)
1336 {
1337 return yyparse ();
1338 }
1339 ]])
1340
1341 AT_BISON_CHECK([[-o input.c input.y]])
1342 AT_COMPILE([[input]])
1343 AT_PARSER_CHECK([[./input]], [[1]], [],
1344 [[syntax error, unexpected 'a', expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B
1345 syntax error, unexpected $end, expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B
1346 ]])
1347
1348 AT_CLEANUP
1349
1350
1351
1352 ## ------------------------------ ##
1353 ## parse.error=verbose overflow. ##
1354 ## ------------------------------ ##
1355
1356 # Imagine the case where YYSTACK_ALLOC_MAXIMUM = YYSIZE_MAXIMUM and an
1357 # invocation of yysyntax_error has caused yymsg_alloc to grow to exactly
1358 # YYSTACK_ALLOC_MAXIMUM (perhaps because the normal doubling of size had
1359 # to be clipped to YYSTACK_ALLOC_MAXIMUM). In an old version of yacc.c,
1360 # a subsequent invocation of yysyntax_error that overflows during its
1361 # size calculation would return YYSIZE_MAXIMUM to yyparse. Then,
1362 # yyparse would invoke yyerror using the old contents of yymsg.
1363
1364 AT_SETUP([[parse.error=verbose overflow]])
1365
1366 AT_DATA_GRAMMAR([input.y],
1367 [[%code {
1368 #include <stdio.h>
1369 void yyerror (char const *);
1370 int yylex (void);
1371
1372 /* This prevents this test case from having to induce error messages
1373 large enough to overflow size_t. */
1374 #define YYSIZE_T unsigned char
1375
1376 /* Bring in malloc and set EXIT_SUCCESS so yacc.c doesn't try to
1377 provide a malloc prototype using our YYSIZE_T. */
1378 #include <stdlib.h>
1379 #ifndef EXIT_SUCCESS
1380 # define EXIT_SUCCESS 0
1381 #endif
1382
1383 /* Max depth is usually much smaller than YYSTACK_ALLOC_MAXIMUM, and
1384 we don't want gcc to warn everywhere this constant would be too big
1385 to make sense for our YYSIZE_T. */
1386 #define YYMAXDEPTH 100
1387 }
1388
1389 %define parse.error verbose
1390
1391 %%
1392
1393 start: syntax_error1 check syntax_error2 ;
1394
1395 // Induce a syntax error message whose total length causes yymsg in
1396 // yyparse to be reallocated to size YYSTACK_ALLOC_MAXIMUM, which
1397 // should be 255. Each token here is 64 bytes.
1398 syntax_error1:
1399 "123456789112345678921234567893123456789412345678951234567896123A"
1400 | "123456789112345678921234567893123456789412345678951234567896123B"
1401 | "123456789112345678921234567893123456789412345678951234567896123C"
1402 | error 'a' 'b' 'c'
1403 ;
1404
1405 check:
1406 {
1407 if (yymsg_alloc != YYSTACK_ALLOC_MAXIMUM
1408 || YYSTACK_ALLOC_MAXIMUM != YYSIZE_MAXIMUM
1409 || YYSIZE_MAXIMUM != 255)
1410 {
1411 fprintf (stderr,
1412 "The assumptions of this test group are no longer\n"
1413 "valid, so it may no longer catch the error it was\n"
1414 "designed to catch. Specifically, the following\n"
1415 "values should all be 255:\n\n");
1416 fprintf (stderr, " yymsg_alloc = %d\n", yymsg_alloc);
1417 fprintf (stderr, " YYSTACK_ALLOC_MAXIMUM = %d\n",
1418 YYSTACK_ALLOC_MAXIMUM);
1419 fprintf (stderr, " YYSIZE_MAXIMUM = %d\n", YYSIZE_MAXIMUM);
1420 YYABORT;
1421 }
1422 }
1423 ;
1424
1425 // Now overflow.
1426 syntax_error2:
1427 "123456789112345678921234567893123456789412345678951234567896123A"
1428 | "123456789112345678921234567893123456789412345678951234567896123B"
1429 | "123456789112345678921234567893123456789412345678951234567896123C"
1430 | "123456789112345678921234567893123456789412345678951234567896123D"
1431 | "123456789112345678921234567893123456789412345678951234567896123E"
1432 ;
1433
1434 %%
1435
1436 void
1437 yyerror (char const *msg)
1438 {
1439 fprintf (stderr, "%s\n", msg);
1440 }
1441
1442 int
1443 yylex (void)
1444 {
1445 /* Induce two syntax error messages (which requires full error
1446 recovery by shifting 3 tokens). */
1447 static char const *input = "abc";
1448 return *input++;
1449 }
1450
1451 int
1452 main (void)
1453 {
1454 /* Push parsers throw away the message buffer between tokens, so skip
1455 this test under maintainer-push-check. */
1456 if (YYPUSH)
1457 return 77;
1458 return yyparse ();
1459 }
1460 ]])
1461
1462 AT_BISON_CHECK([[-o input.c input.y]])
1463
1464 # gcc warns about tautologies and fallacies involving comparisons for
1465 # unsigned char. However, it doesn't produce these same warnings for
1466 # size_t and many other types when the warnings would seem to make just
1467 # as much sense. We ignore the warnings.
1468 [CFLAGS="$NO_WERROR_CFLAGS"]
1469 AT_COMPILE([[input]])
1470
1471 AT_PARSER_CHECK([[./input]], [[2]], [],
1472 [[syntax error, unexpected 'a', expecting 123456789112345678921234567893123456789412345678951234567896123A or 123456789112345678921234567893123456789412345678951234567896123B or 123456789112345678921234567893123456789412345678951234567896123C
1473 syntax error
1474 memory exhausted
1475 ]])
1476
1477 AT_CLEANUP
1478
1479
1480
1481 ## ------------------------ ##
1482 ## LAC: Exploratory stack. ##
1483 ## ------------------------ ##
1484
1485 AT_SETUP([[LAC: Exploratory stack]])
1486
1487 m4_pushdef([AT_LAC_CHECK], [
1488
1489 AT_BISON_OPTION_PUSHDEFS([$1])
1490
1491 AT_DATA_GRAMMAR([input.y],
1492 [[%code {
1493 #include <stdio.h>
1494 void yyerror (char const *);
1495 int yylex (]AT_PURE_IF([[YYSTYPE *]], [[void]])[);
1496 }
1497
1498 ]$1[
1499 %define parse.error verbose
1500 %token 'c'
1501
1502 %%
1503
1504 // default reductions in inconsistent states
1505 // v v v v v v v v v v v v v v
1506 S: A B A A B A A A A B A A A A A A A B C C A A A A A A A A A A A A B ;
1507 // ^ ^ ^
1508 // LAC reallocs
1509
1510 A: 'a' | /*empty*/ { printf ("inconsistent default reduction\n"); } ;
1511 B: 'b' ;
1512 C: /*empty*/ { printf ("consistent default reduction\n"); } ;
1513
1514 %%
1515
1516 void
1517 yyerror (char const *msg)
1518 {
1519 fprintf (stderr, "%s\n", msg);
1520 }
1521
1522 int
1523 yylex (]AT_PURE_IF([[YYSTYPE *v]], [[void]])[)
1524 {
1525 static char const *input = "bbbbc";]AT_PURE_IF([[
1526 *v = 0;]])[
1527 return *input++;
1528 }
1529
1530 int
1531 main (void)
1532 {
1533 yydebug = 1;
1534 return yyparse ();
1535 }
1536 ]])
1537
1538 AT_BISON_CHECK([[-Dparse.lac=full -Dparse.lac.es-capacity-initial=1 \
1539 -Dparse.lac.memory-trace=full \
1540 -t -o input.c input.y]], [[0]], [],
1541 [[input.y: conflicts: 21 shift/reduce
1542 ]])
1543 AT_COMPILE([[input]])
1544 AT_PARSER_CHECK([[./input > stdout.txt 2> stderr.txt]], [[1]])
1545
1546 # Make sure syntax error doesn't forget that 'a' is expected. It would
1547 # be forgotten without lookahead correction.
1548 AT_CHECK([[grep 'syntax error,' stderr.txt]], [[0]],
1549 [[syntax error, unexpected 'c', expecting 'a' or 'b'
1550 ]])
1551
1552 # Check number of default reductions in inconsistent states to be sure
1553 # syntax error is detected before unnecessary reductions are performed.
1554 AT_CHECK([[perl -0777 -ne 'print s/inconsistent default reduction//g;' \
1555 < stdout.txt || exit 77]], [[0]], [[14]])
1556
1557 # Check number of default reductions in consistent states to be sure
1558 # it is performed before the syntax error is detected.
1559 AT_CHECK([[perl -0777 -ne 'print s/\bconsistent default reduction//g;' \
1560 < stdout.txt || exit 77]], [[0]], [[2]])
1561
1562 # Check number of reallocs to be sure reallocated memory isn't somehow
1563 # lost between LAC invocations.
1564 AT_CHECK([[perl -0777 -ne 'print s/\(realloc//g;' < stderr.txt \
1565 || exit 77]], [[0]], [[3]])
1566
1567 AT_BISON_OPTION_POPDEFS
1568 ])
1569
1570 AT_LAC_CHECK([[%define api.push-pull pull]])
1571 AT_LAC_CHECK([[%define api.push-pull pull %define api.pure]])
1572 AT_LAC_CHECK([[%define api.push-pull both]])
1573 AT_LAC_CHECK([[%define api.push-pull both %define api.pure]])
1574
1575 m4_popdef([AT_LAC_CHECK])
1576
1577 AT_CLEANUP
1578
1579
1580
1581 ## ------------------------ ##
1582 ## LAC: Memory exhaustion. ##
1583 ## ------------------------ ##
1584
1585 AT_SETUP([[LAC: Memory exhaustion]])
1586
1587 m4_pushdef([AT_LAC_CHECK], [
1588
1589 AT_DATA_GRAMMAR([input.y],
1590 [[%code {
1591 #include <stdio.h>
1592 void yyerror (char const *);
1593 int yylex (void);
1594 #define YYMAXDEPTH 8
1595 }
1596
1597 %error-verbose
1598
1599 %%
1600
1601 S: A A A A A A A A A ;
1602 A: /*empty*/ | 'a' ;
1603
1604 %%
1605
1606 void
1607 yyerror (char const *msg)
1608 {
1609 fprintf (stderr, "%s\n", msg);
1610 }
1611
1612 int
1613 yylex (void)
1614 {
1615 static char const *input = "]$1[";
1616 return *input++;
1617 }
1618
1619 int
1620 main (void)
1621 {
1622 yydebug = 1;
1623 return yyparse ();
1624 }
1625 ]])
1626
1627 AT_BISON_CHECK([[-Dparse.lac=full -Dparse.lac.es-capacity-initial=1 \
1628 -t -o input.c input.y]], [[0]], [],
1629 [[input.y: conflicts: 8 shift/reduce
1630 ]])
1631 AT_COMPILE([[input]])
1632
1633 ])
1634
1635 # Check for memory exhaustion during parsing.
1636 AT_LAC_CHECK([[]])
1637 AT_PARSER_CHECK([[./input]], [[2]], [[]],
1638 [[Starting parse
1639 Entering state 0
1640 Reading a token: Now at end of input.
1641 LAC: initial context established for $end
1642 LAC: checking lookahead $end: R2 G3 R2 G5 R2 G6 R2 G7 R2 G8 R2 G9 R2 G10 R2 G11 R2 (max size exceeded)
1643 memory exhausted
1644 Cleanup: discarding lookahead token $end ()
1645 Stack now 0
1646 ]])
1647
1648 # Induce an immediate syntax error with an undefined token, and check
1649 # for memory exhaustion while building syntax error message.
1650 AT_LAC_CHECK([[z]], [[0]])
1651 AT_PARSER_CHECK([[./input]], [[2]], [[]],
1652 [[Starting parse
1653 Entering state 0
1654 Reading a token: Next token is token $undefined ()
1655 LAC: initial context established for $undefined
1656 LAC: checking lookahead $undefined: Always Err
1657 Constructing syntax error message
1658 LAC: checking lookahead $end: R2 G3 R2 G5 R2 G6 R2 G7 R2 G8 R2 G9 R2 G10 R2 G11 R2 (max size exceeded)
1659 syntax error
1660 memory exhausted
1661 Cleanup: discarding lookahead token $undefined ()
1662 Stack now 0
1663 ]])
1664
1665 m4_popdef([AT_LAC_CHECK])
1666
1667 AT_CLEANUP