cgram.y revision 1.435 1 %{
2 /* $NetBSD: cgram.y,v 1.435 2023/04/22 17:49:15 rillig Exp $ */
3
4 /*
5 * Copyright (c) 1996 Christopher G. Demetriou. All Rights Reserved.
6 * Copyright (c) 1994, 1995 Jochen Pohl
7 * All Rights Reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by Jochen Pohl for
20 * The NetBSD Project.
21 * 4. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 #if defined(__RCSID)
38 __RCSID("$NetBSD: cgram.y,v 1.435 2023/04/22 17:49:15 rillig Exp $");
39 #endif
40
41 #include <limits.h>
42 #include <stdlib.h>
43 #include <string.h>
44
45 #include "lint1.h"
46
47 extern char *yytext;
48
49 /*
50 * Contains the level of current declaration, used for symbol table entries.
51 * 0 is the top-level, > 0 is inside a function body.
52 */
53 int block_level;
54
55 /*
56 * level for memory allocation. Normally the same as block_level.
57 * An exception is the declaration of arguments in prototypes. Memory
58 * for these can't be freed after the declaration, but symbols must
59 * be removed from the symbol table after the declaration.
60 */
61 size_t mem_block_level;
62
63 /*
64 * Save the no-warns state and restore it to avoid the problem where
65 * if (expr) { stmt } / * NOLINT * / stmt;
66 */
67 #define LWARN_NOTHING_SAVED (-3)
68 static int saved_lwarn = LWARN_NOTHING_SAVED;
69
70 static void cgram_declare(sym_t *, bool, sbuf_t *);
71 static void read_until_rparen(void);
72 static sym_t *symbolrename(sym_t *, sbuf_t *);
73
74
75 /* ARGSUSED */
76 static void
77 clear_warning_flags_loc(const char *file, size_t line)
78 {
79 debug_step("%s:%zu: clearing flags", file, line);
80 clear_warn_flags();
81 saved_lwarn = LWARN_NOTHING_SAVED;
82 }
83
84 /* ARGSUSED */
85 static void
86 save_warning_flags_loc(const char *file, size_t line)
87 {
88 /*
89 * There used to be an assertion that saved_lwarn is
90 * LWARN_NOTHING_SAVED here, but that triggered for the following
91 * code:
92 *
93 * void function(int x) { if (x > 0) if (x > 1) return; }
94 *
95 * It didn't trigger if the inner 'if' was enclosed in braces though.
96 *
97 * TODO: If actually needed, add support for nested suppression of
98 * warnings.
99 */
100 debug_step("%s:%zu: saving flags %d", file, line, lwarn);
101 saved_lwarn = lwarn;
102 }
103
104 /* ARGSUSED */
105 static void
106 restore_warning_flags_loc(const char *file, size_t line)
107 {
108 if (saved_lwarn != LWARN_NOTHING_SAVED) {
109 lwarn = saved_lwarn;
110 debug_step("%s:%zu: restoring flags %d", file, line, lwarn);
111 /*
112 * Do not set 'saved_lwarn = LWARN_NOTHING_SAVED' here, to
113 * avoid triggering the assertion in save_warning_flags_loc.
114 */
115 } else
116 clear_warning_flags_loc(file, line);
117 }
118
119 #define clear_warning_flags() clear_warning_flags_loc(__FILE__, __LINE__)
120 #define save_warning_flags() save_warning_flags_loc(__FILE__, __LINE__)
121 #define restore_warning_flags() restore_warning_flags_loc(__FILE__, __LINE__)
122
123 /* unbind the anonymous struct members from the struct */
124 static void
125 anonymize(sym_t *s)
126 {
127 for ( ; s != NULL; s = s->s_next)
128 s->u.s_member.sm_sou_type = NULL;
129 }
130
131 static bool
132 is_either(const char *s, const char *a, const char *b)
133 {
134 return strcmp(s, a) == 0 || strcmp(s, b) == 0;
135 }
136
137 #if YYDEBUG && (YYBYACC || YYBISON)
138 #define YYSTYPE_TOSTRING cgram_to_string
139 #endif
140 #if YYDEBUG && YYBISON
141 #define YYPRINT cgram_print
142 #endif
143
144 %}
145
146 %expect 131
147
148 %union {
149 val_t *y_val;
150 sbuf_t *y_name;
151 sym_t *y_sym;
152 op_t y_op;
153 scl_t y_scl;
154 tspec_t y_tspec;
155 tqual_t y_tqual;
156 type_t *y_type;
157 tnode_t *y_tnode;
158 range_t y_range;
159 strg_t *y_string;
160 qual_ptr *y_qual_ptr;
161 bool y_seen_statement;
162 struct generic_association *y_generic;
163 struct array_size y_array_size;
164 bool y_in_system_header;
165 };
166
167 %token T_LBRACE T_RBRACE T_LBRACK T_RBRACK T_LPAREN T_RPAREN
168 %token T_POINT T_ARROW
169 %token T_COMPLEMENT T_LOGNOT
170 %token <y_op> T_INCDEC
171 %token T_SIZEOF
172 %token T_BUILTIN_OFFSETOF
173 %token T_TYPEOF
174 %token T_EXTENSION
175 %token T_ALIGNAS
176 %token T_ALIGNOF
177 %token T_ASTERISK
178 %token <y_op> T_MULTIPLICATIVE
179 %token <y_op> T_ADDITIVE
180 %token <y_op> T_SHIFT
181 %token <y_op> T_RELATIONAL
182 %token <y_op> T_EQUALITY
183 %token T_AMPER
184 %token T_BITXOR
185 %token T_BITOR
186 %token T_LOGAND
187 %token T_LOGOR
188 %token T_QUEST
189 %token T_COLON
190 %token T_ASSIGN
191 %token <y_op> T_OPASSIGN
192 %token T_COMMA
193 %token T_SEMI
194 %token T_ELLIPSIS
195 %token T_REAL
196 %token T_IMAG
197 %token T_GENERIC
198 %token T_NORETURN
199
200 /* storage classes (extern, static, auto, register and typedef) */
201 %token <y_scl> T_SCLASS
202
203 /*
204 * predefined type keywords (char, int, short, long, unsigned, signed,
205 * float, double, void); see T_TYPENAME for types from typedef
206 */
207 %token <y_tspec> T_TYPE
208
209 /* qualifiers (const, volatile, restrict, _Thread_local) */
210 %token <y_tqual> T_QUAL
211 %token <y_tqual> T_ATOMIC
212
213 /* struct or union */
214 %token <y_tspec> T_STRUCT_OR_UNION
215
216 /* remaining keywords */
217 %token T_ASM
218 %token T_BREAK
219 %token T_CASE
220 %token T_CONTINUE
221 %token T_DEFAULT
222 %token T_DO
223 %token T_ELSE
224 %token T_ENUM
225 %token T_FOR
226 %token T_GOTO
227 %token T_IF
228 %token T_PACKED
229 %token T_RETURN
230 %token T_SWITCH
231 %token T_SYMBOLRENAME
232 %token T_WHILE
233 %token T_STATIC_ASSERT
234
235 %token T_ATTRIBUTE
236
237 %left T_THEN
238 %left T_ELSE
239 %right T_QUEST T_COLON
240 %left T_LOGOR
241 %left T_LOGAND
242 %left T_BITOR
243 %left T_BITXOR
244 %left T_AMPER
245 %left T_EQUALITY
246 %left T_RELATIONAL
247 %left T_SHIFT
248 %left T_ADDITIVE
249 %left T_ASTERISK T_MULTIPLICATIVE
250
251 %token <y_name> T_NAME
252 %token <y_name> T_TYPENAME
253 %token <y_val> T_CON
254 %token <y_string> T_STRING
255
256 %type <y_sym> identifier_sym
257 %type <y_name> identifier
258 %type <y_string> string
259
260 %type <y_tnode> primary_expression
261 %type <y_tnode> generic_selection
262 %type <y_generic> generic_assoc_list
263 %type <y_generic> generic_association
264 %type <y_tnode> postfix_expression
265 %type <y_tnode> gcc_statement_expr_list
266 %type <y_tnode> gcc_statement_expr_item
267 %type <y_op> point_or_arrow
268 %type <y_tnode> argument_expression_list
269 %type <y_tnode> unary_expression
270 %type <y_tnode> cast_expression
271 %type <y_tnode> conditional_expression
272 %type <y_tnode> assignment_expression
273 %type <y_tnode> expression_opt
274 %type <y_tnode> expression
275 %type <y_tnode> constant_expr
276
277 %type <y_type> begin_type_typespec
278 %type <y_type> type_specifier
279 %type <y_type> notype_type_specifier
280 %type <y_type> atomic_type_specifier
281 %type <y_type> struct_or_union_specifier
282 %type <y_tspec> struct_or_union
283 %type <y_sym> braced_struct_declaration_list
284 %type <y_sym> struct_declaration_list_with_rbrace
285 %type <y_sym> struct_declaration_list
286 %type <y_sym> struct_declaration
287 %type <y_sym> notype_struct_declarators
288 %type <y_sym> type_struct_declarators
289 %type <y_sym> notype_struct_declarator
290 %type <y_sym> type_struct_declarator
291 %type <y_type> enum_specifier
292 %type <y_sym> enum_declaration
293 %type <y_sym> enums_with_opt_comma
294 %type <y_sym> enumerator_list
295 %type <y_sym> enumerator
296 %type <y_tqual> type_qualifier
297 %type <y_qual_ptr> pointer
298 %type <y_qual_ptr> asterisk
299 %type <y_qual_ptr> type_qualifier_list_opt
300 %type <y_qual_ptr> type_qualifier_list
301 %type <y_qual_ptr> type_qualifier_list_elem
302 %type <y_sym> notype_declarator
303 %type <y_sym> type_declarator
304 %type <y_sym> notype_direct_declarator
305 %type <y_sym> type_direct_declarator
306 %type <y_sym> type_param_declarator
307 %type <y_sym> notype_param_declarator
308 %type <y_sym> direct_param_declarator
309 %type <y_sym> direct_notype_param_declarator
310 %type <y_sym> param_list
311 %type <y_array_size> array_size_opt
312 %type <y_tnode> array_size
313 %type <y_sym> identifier_list
314 %type <y_type> type_name
315 %type <y_sym> abstract_declaration
316 %type <y_sym> abstract_declarator
317 %type <y_sym> direct_abstract_declarator
318 %type <y_sym> abstract_decl_param_list
319 %type <y_sym> vararg_parameter_type_list
320 %type <y_sym> parameter_type_list
321 %type <y_sym> parameter_declaration
322 %type <y_range> range
323 %type <y_name> asm_or_symbolrename_opt
324
325 %type <y_seen_statement> block_item_list
326 %type <y_seen_statement> block_item
327 %type <y_tnode> do_while_expr
328 %type <y_sym> func_declarator
329 %type <y_in_system_header> sys
330
331 %{
332 #if YYDEBUG && YYBISON
333 static inline void cgram_print(FILE *, int, YYSTYPE);
334 #endif
335 %}
336
337 %%
338
339 program:
340 /* empty */ {
341 /* TODO: Make this an error in C99 mode as well. */
342 if (!allow_trad && !allow_c99) {
343 /* empty translation unit */
344 error(272);
345 } else if (allow_c90) {
346 /* empty translation unit */
347 warning(272);
348 }
349 }
350 | translation_unit
351 ;
352
353 identifier_sym: /* helper for struct/union/enum */
354 identifier {
355 $$ = getsym($1);
356 }
357 ;
358
359 /* K&R ???, C90 ???, C99 6.4.2.1, C11 ??? */
360 identifier:
361 T_NAME {
362 debug_step("cgram: name '%s'", $1->sb_name);
363 $$ = $1;
364 }
365 | T_TYPENAME {
366 debug_step("cgram: typename '%s'", $1->sb_name);
367 $$ = $1;
368 }
369 ;
370
371 /* see C99 6.4.5, string literals are joined by 5.1.1.2 */
372 string:
373 T_STRING
374 | string T_STRING {
375 if (!allow_c90) {
376 /* concatenated strings are illegal in traditional C */
377 warning(219);
378 }
379 $$ = cat_strings($1, $2);
380 }
381 ;
382
383 /* K&R 7.1, C90 ???, C99 6.5.1, C11 6.5.1 */
384 primary_expression:
385 T_NAME {
386 bool sys_name, sys_next;
387 sys_name = in_system_header;
388 if (yychar < 0)
389 yychar = yylex();
390 sys_next = in_system_header;
391 in_system_header = sys_name;
392 $$ = build_name(getsym($1), yychar == T_LPAREN);
393 in_system_header = sys_next;
394 }
395 | T_CON {
396 $$ = build_constant(gettyp($1->v_tspec), $1);
397 }
398 | string {
399 $$ = build_string($1);
400 }
401 | T_LPAREN expression T_RPAREN {
402 if ($2 != NULL)
403 $2->tn_parenthesized = true;
404 $$ = $2;
405 }
406 | generic_selection
407 /* GCC primary-expression, see c_parser_postfix_expression */
408 | T_BUILTIN_OFFSETOF T_LPAREN type_name T_COMMA identifier T_RPAREN {
409 symtyp = FMEMBER;
410 $$ = build_offsetof($3, getsym($5));
411 }
412 ;
413
414 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1 */
415 generic_selection:
416 T_GENERIC T_LPAREN assignment_expression T_COMMA
417 generic_assoc_list T_RPAREN {
418 /* generic selection requires C11 or later */
419 c11ism(345);
420 $$ = build_generic_selection($3, $5);
421 }
422 ;
423
424 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1 */
425 generic_assoc_list:
426 generic_association
427 | generic_assoc_list T_COMMA generic_association {
428 $3->ga_prev = $1;
429 $$ = $3;
430 }
431 ;
432
433 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1 */
434 generic_association:
435 type_name T_COLON assignment_expression {
436 $$ = block_zero_alloc(sizeof(*$$));
437 $$->ga_arg = $1;
438 $$->ga_result = $3;
439 }
440 | T_DEFAULT T_COLON assignment_expression {
441 $$ = block_zero_alloc(sizeof(*$$));
442 $$->ga_arg = NULL;
443 $$->ga_result = $3;
444 }
445 ;
446
447 /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2 */
448 postfix_expression:
449 primary_expression
450 | postfix_expression T_LBRACK sys expression T_RBRACK {
451 $$ = build_unary(INDIR, $3, build_binary($1, PLUS, $3, $4));
452 }
453 | postfix_expression T_LPAREN sys T_RPAREN {
454 $$ = build_function_call($1, $3, NULL);
455 }
456 | postfix_expression T_LPAREN sys argument_expression_list T_RPAREN {
457 $$ = build_function_call($1, $3, $4);
458 }
459 | postfix_expression point_or_arrow sys T_NAME {
460 $$ = build_member_access($1, $2, $3, $4);
461 }
462 | postfix_expression T_INCDEC sys {
463 $$ = build_unary($2 == INC ? INCAFT : DECAFT, $3, $1);
464 }
465 | T_LPAREN type_name T_RPAREN { /* C99 6.5.2.5 "Compound literals" */
466 sym_t *tmp = mktempsym($2);
467 begin_initialization(tmp);
468 cgram_declare(tmp, true, NULL);
469 } init_lbrace initializer_list comma_opt init_rbrace {
470 if (!allow_c99)
471 /* compound literals are a C99/GCC extension */
472 gnuism(319);
473 $$ = build_name(current_initsym(), false);
474 end_initialization();
475 }
476 | T_LPAREN compound_statement_lbrace {
477 begin_statement_expr();
478 } gcc_statement_expr_list {
479 do_statement_expr($4);
480 } compound_statement_rbrace T_RPAREN {
481 $$ = end_statement_expr();
482 }
483 ;
484
485 comma_opt: /* helper for 'postfix_expression' */
486 /* empty */
487 | T_COMMA
488 ;
489
490 /*
491 * The inner part of a GCC statement-expression of the form ({ ... }).
492 *
493 * https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html
494 */
495 gcc_statement_expr_list:
496 gcc_statement_expr_item
497 | gcc_statement_expr_list gcc_statement_expr_item {
498 $$ = $2;
499 }
500 ;
501
502 gcc_statement_expr_item:
503 declaration_or_error {
504 clear_warning_flags();
505 $$ = NULL;
506 }
507 | non_expr_statement {
508 $$ = expr_alloc_tnode();
509 $$->tn_type = gettyp(VOID);
510 }
511 | expression T_SEMI {
512 if ($1 == NULL) { /* in case of syntax errors */
513 $$ = expr_alloc_tnode();
514 $$->tn_type = gettyp(VOID);
515 } else {
516 /* XXX: do that only on the last name */
517 if ($1->tn_op == NAME)
518 $1->tn_sym->s_used = true;
519 expr($1, false, false, false, false);
520 seen_fallthrough = false;
521 $$ = $1;
522 }
523 }
524 ;
525
526 point_or_arrow: /* helper for 'postfix_expression' */
527 T_POINT {
528 symtyp = FMEMBER;
529 $$ = POINT;
530 }
531 | T_ARROW {
532 symtyp = FMEMBER;
533 $$ = ARROW;
534 }
535 ;
536
537 /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2 */
538 argument_expression_list:
539 assignment_expression {
540 $$ = build_function_argument(NULL, $1);
541 }
542 | argument_expression_list T_COMMA assignment_expression {
543 $$ = build_function_argument($1, $3);
544 }
545 ;
546
547 /* K&R 7.2, C90 ???, C99 6.5.3, C11 6.5.3 */
548 unary_expression:
549 postfix_expression
550 | T_INCDEC sys unary_expression {
551 $$ = build_unary($1 == INC ? INCBEF : DECBEF, $2, $3);
552 }
553 | T_AMPER sys cast_expression {
554 $$ = build_unary(ADDR, $2, $3);
555 }
556 | T_ASTERISK sys cast_expression {
557 $$ = build_unary(INDIR, $2, $3);
558 }
559 | T_ADDITIVE sys cast_expression {
560 if (!allow_c90 && $1 == PLUS) {
561 /* unary '+' is illegal in traditional C */
562 warning(100);
563 }
564 $$ = build_unary($1 == PLUS ? UPLUS : UMINUS, $2, $3);
565 }
566 | T_COMPLEMENT sys cast_expression {
567 $$ = build_unary(COMPL, $2, $3);
568 }
569 | T_LOGNOT sys cast_expression {
570 $$ = build_unary(NOT, $2, $3);
571 }
572 | T_REAL sys cast_expression { /* GCC c_parser_unary_expression */
573 $$ = build_unary(REAL, $2, $3);
574 }
575 | T_IMAG sys cast_expression { /* GCC c_parser_unary_expression */
576 $$ = build_unary(IMAG, $2, $3);
577 }
578 | T_EXTENSION cast_expression { /* GCC c_parser_unary_expression */
579 $$ = $2;
580 }
581 | T_SIZEOF unary_expression {
582 $$ = $2 == NULL ? NULL : build_sizeof($2->tn_type);
583 if ($$ != NULL)
584 check_expr_misc($2,
585 false, false, false, false, false, true);
586 }
587 | T_SIZEOF T_LPAREN type_name T_RPAREN {
588 $$ = build_sizeof($3);
589 }
590 | T_ALIGNOF unary_expression {
591 /* non type argument to alignof is a GCC extension */
592 gnuism(349);
593 lint_assert($2 != NULL);
594 $$ = build_alignof($2->tn_type);
595 }
596 /* K&R ---, C90 ---, C99 ---, C11 6.5.3 */
597 | T_ALIGNOF T_LPAREN type_name T_RPAREN {
598 /* TODO: c11ism */
599 $$ = build_alignof($3);
600 }
601 ;
602
603 /* The rule 'unary_operator' is inlined into unary_expression. */
604
605 /* K&R 7.2, C90 ???, C99 6.5.4, C11 6.5.4 */
606 cast_expression:
607 unary_expression
608 | T_LPAREN type_name T_RPAREN cast_expression {
609 $$ = cast($4, $2);
610 }
611 ;
612
613 expression_opt:
614 /* empty */ {
615 $$ = NULL;
616 }
617 | expression
618 ;
619
620 /* 'conditional_expression' also implements 'multiplicative_expression'. */
621 /* 'conditional_expression' also implements 'additive_expression'. */
622 /* 'conditional_expression' also implements 'shift_expression'. */
623 /* 'conditional_expression' also implements 'relational_expression'. */
624 /* 'conditional_expression' also implements 'equality_expression'. */
625 /* 'conditional_expression' also implements 'AND_expression'. */
626 /* 'conditional_expression' also implements 'exclusive_OR_expression'. */
627 /* 'conditional_expression' also implements 'inclusive_OR_expression'. */
628 /* 'conditional_expression' also implements 'logical_AND_expression'. */
629 /* 'conditional_expression' also implements 'logical_OR_expression'. */
630 /* K&R ???, C90 ???, C99 6.5.5 to 6.5.15, C11 6.5.5 to 6.5.15 */
631 conditional_expression:
632 cast_expression
633 | conditional_expression T_ASTERISK sys conditional_expression {
634 $$ = build_binary($1, MULT, $3, $4);
635 }
636 | conditional_expression T_MULTIPLICATIVE sys conditional_expression {
637 $$ = build_binary($1, $2, $3, $4);
638 }
639 | conditional_expression T_ADDITIVE sys conditional_expression {
640 $$ = build_binary($1, $2, $3, $4);
641 }
642 | conditional_expression T_SHIFT sys conditional_expression {
643 $$ = build_binary($1, $2, $3, $4);
644 }
645 | conditional_expression T_RELATIONAL sys conditional_expression {
646 $$ = build_binary($1, $2, $3, $4);
647 }
648 | conditional_expression T_EQUALITY sys conditional_expression {
649 $$ = build_binary($1, $2, $3, $4);
650 }
651 | conditional_expression T_AMPER sys conditional_expression {
652 $$ = build_binary($1, BITAND, $3, $4);
653 }
654 | conditional_expression T_BITXOR sys conditional_expression {
655 $$ = build_binary($1, BITXOR, $3, $4);
656 }
657 | conditional_expression T_BITOR sys conditional_expression {
658 $$ = build_binary($1, BITOR, $3, $4);
659 }
660 | conditional_expression T_LOGAND sys conditional_expression {
661 $$ = build_binary($1, LOGAND, $3, $4);
662 }
663 | conditional_expression T_LOGOR sys conditional_expression {
664 $$ = build_binary($1, LOGOR, $3, $4);
665 }
666 | conditional_expression T_QUEST sys
667 expression T_COLON sys conditional_expression {
668 $$ = build_binary($1, QUEST, $3,
669 build_binary($4, COLON, $6, $7));
670 }
671 ;
672
673 /* K&R ???, C90 ???, C99 6.5.16, C11 6.5.16 */
674 assignment_expression:
675 conditional_expression
676 | unary_expression T_ASSIGN sys assignment_expression {
677 $$ = build_binary($1, ASSIGN, $3, $4);
678 }
679 | unary_expression T_OPASSIGN sys assignment_expression {
680 $$ = build_binary($1, $2, $3, $4);
681 }
682 ;
683
684 /* K&R ???, C90 ???, C99 6.5.17, C11 6.5.17 */
685 expression:
686 assignment_expression
687 | expression T_COMMA sys assignment_expression {
688 $$ = build_binary($1, COMMA, $3, $4);
689 }
690 ;
691
692 constant_expr: /* C99 6.6 */
693 conditional_expression
694 ;
695
696 declaration_or_error:
697 declaration
698 | error T_SEMI
699 ;
700
701 declaration: /* C99 6.7 */
702 begin_type_declmods end_type T_SEMI {
703 if (dcs->d_scl == TYPEDEF) {
704 /* typedef declares no type name */
705 warning(72);
706 } else {
707 /* empty declaration */
708 warning(2);
709 }
710 }
711 | begin_type_declmods end_type notype_init_declarators T_SEMI {
712 if (dcs->d_scl == TYPEDEF) {
713 /* syntax error '%s' */
714 error(249, "missing base type for typedef");
715 } else {
716 /* old-style declaration; add 'int' */
717 error(1);
718 }
719 }
720 | begin_type_declaration_specifiers end_type T_SEMI {
721 if (dcs->d_scl == TYPEDEF) {
722 /* typedef declares no type name */
723 warning(72);
724 } else if (!dcs->d_nonempty_decl) {
725 /* empty declaration */
726 warning(2);
727 }
728 }
729 | begin_type_declaration_specifiers end_type
730 type_init_declarators T_SEMI
731 | static_assert_declaration
732 ;
733
734 begin_type_declaration_specifiers: /* see C99 6.7 */
735 begin_type_typespec {
736 dcs_add_type($1);
737 }
738 | begin_type_declmods type_specifier {
739 dcs_add_type($2);
740 }
741 | type_attribute begin_type_declaration_specifiers
742 | begin_type_declaration_specifiers declmod
743 | begin_type_declaration_specifiers notype_type_specifier {
744 dcs_add_type($2);
745 }
746 ;
747
748 begin_type_declmods: /* see C99 6.7 */
749 begin_type type_qualifier {
750 dcs_add_qualifier($2);
751 }
752 | begin_type T_SCLASS {
753 dcs_add_storage_class($2);
754 }
755 | begin_type_declmods declmod
756 ;
757
758 begin_type_specifier_qualifier_list: /* see C11 6.7.2.1 */
759 begin_type_specifier_qualifier_list_postfix
760 | type_attribute_list begin_type_specifier_qualifier_list_postfix
761 ;
762
763 begin_type_specifier_qualifier_list_postfix:
764 begin_type_typespec {
765 dcs_add_type($1);
766 }
767 | begin_type_qualifier_list type_specifier {
768 dcs_add_type($2);
769 }
770 | begin_type_specifier_qualifier_list_postfix type_qualifier {
771 dcs_add_qualifier($2);
772 }
773 | begin_type_specifier_qualifier_list_postfix notype_type_specifier {
774 dcs_add_type($2);
775 }
776 | begin_type_specifier_qualifier_list_postfix type_attribute
777 ;
778
779 begin_type_typespec:
780 begin_type notype_type_specifier {
781 $$ = $2;
782 }
783 | begin_type T_TYPENAME {
784 $$ = getsym($2)->s_type;
785 }
786 ;
787
788 begin_type_qualifier_list:
789 begin_type type_qualifier {
790 dcs_add_qualifier($2);
791 }
792 | begin_type_qualifier_list type_qualifier {
793 dcs_add_qualifier($2);
794 }
795 ;
796
797 declmod:
798 type_qualifier {
799 dcs_add_qualifier($1);
800 }
801 | T_SCLASS {
802 dcs_add_storage_class($1);
803 }
804 | type_attribute_list
805 ;
806
807 type_attribute_list_opt:
808 /* empty */
809 | type_attribute_list
810 ;
811
812 type_attribute_list:
813 type_attribute
814 | type_attribute_list type_attribute
815 ;
816
817 type_attribute_opt:
818 /* empty */
819 | type_attribute
820 ;
821
822 type_attribute: /* See C11 6.7 declaration-specifiers */
823 gcc_attribute_specifier
824 | T_ALIGNAS T_LPAREN type_specifier T_RPAREN /* C11 6.7.5 */
825 | T_ALIGNAS T_LPAREN constant_expr T_RPAREN /* C11 6.7.5 */
826 | T_PACKED {
827 dcs_add_packed();
828 }
829 | T_NORETURN
830 ;
831
832 begin_type:
833 /* empty */ {
834 dcs_begin_type();
835 }
836 ;
837
838 end_type:
839 /* empty */ {
840 dcs_end_type();
841 }
842 ;
843
844 type_specifier: /* C99 6.7.2 */
845 notype_type_specifier
846 | T_TYPENAME {
847 $$ = getsym($1)->s_type;
848 }
849 ;
850
851 notype_type_specifier: /* see C99 6.7.2 */
852 T_TYPE {
853 $$ = gettyp($1);
854 }
855 | T_TYPEOF T_LPAREN expression T_RPAREN { /* GCC extension */
856 $$ = $3 != NULL ? block_dup_type($3->tn_type) : gettyp(INT);
857 $$->t_typeof = true;
858 }
859 | atomic_type_specifier
860 | struct_or_union_specifier {
861 end_declaration_level();
862 $$ = $1;
863 }
864 | enum_specifier {
865 end_declaration_level();
866 $$ = $1;
867 }
868 ;
869
870 /* K&R ---, C90 ---, C99 ---, C11 6.7.2.4 */
871 atomic_type_specifier:
872 atomic T_LPAREN type_name T_RPAREN {
873 $$ = $3;
874 }
875 ;
876
877 struct_or_union_specifier: /* C99 6.7.2.1 */
878 struct_or_union identifier_sym {
879 /*
880 * STDC requires that "struct a;" always introduces
881 * a new tag if "a" is not declared at current level
882 *
883 * yychar is valid because otherwise the parser would not
884 * have been able to decide if it must shift or reduce
885 */
886 $$ = make_tag_type($2, $1, false, yychar == T_SEMI);
887 }
888 | struct_or_union identifier_sym {
889 dcs->d_tagtyp = make_tag_type($2, $1, true, false);
890 } braced_struct_declaration_list {
891 $$ = complete_tag_struct_or_union(dcs->d_tagtyp, $4);
892 }
893 | struct_or_union {
894 dcs->d_tagtyp = make_tag_type(NULL, $1, true, false);
895 } braced_struct_declaration_list {
896 $$ = complete_tag_struct_or_union(dcs->d_tagtyp, $3);
897 }
898 | struct_or_union error {
899 symtyp = FVFT;
900 $$ = gettyp(INT);
901 }
902 ;
903
904 struct_or_union: /* C99 6.7.2.1 */
905 T_STRUCT_OR_UNION {
906 symtyp = FTAG;
907 begin_declaration_level($1 == STRUCT
908 ? DK_STRUCT_MEMBER
909 : DK_UNION_MEMBER);
910 dcs->d_offset_in_bits = 0;
911 dcs->d_sou_align_in_bits = CHAR_SIZE;
912 $$ = $1;
913 }
914 | struct_or_union type_attribute
915 ;
916
917 braced_struct_declaration_list: /* see C99 6.7.2.1 */
918 struct_declaration_lbrace struct_declaration_list_with_rbrace {
919 $$ = $2;
920 }
921 ;
922
923 struct_declaration_lbrace: /* see C99 6.7.2.1 */
924 T_LBRACE {
925 symtyp = FVFT;
926 }
927 ;
928
929 struct_declaration_list_with_rbrace: /* see C99 6.7.2.1 */
930 struct_declaration_list T_RBRACE
931 | T_RBRACE {
932 /* XXX: This is not allowed by any C standard. */
933 $$ = NULL;
934 }
935 ;
936
937 struct_declaration_list: /* C99 6.7.2.1 */
938 struct_declaration
939 | struct_declaration_list struct_declaration {
940 $$ = concat_lists($1, $2);
941 }
942 ;
943
944 struct_declaration: /* C99 6.7.2.1 */
945 begin_type_qualifier_list end_type {
946 /* ^^ There is no check for the missing type-specifier. */
947 /* too late, i know, but getsym() compensates it */
948 symtyp = FMEMBER;
949 } notype_struct_declarators type_attribute_opt T_SEMI {
950 symtyp = FVFT;
951 $$ = $4;
952 }
953 | begin_type_specifier_qualifier_list end_type {
954 symtyp = FMEMBER;
955 } type_struct_declarators type_attribute_opt T_SEMI {
956 symtyp = FVFT;
957 $$ = $4;
958 }
959 | begin_type_qualifier_list end_type type_attribute_opt T_SEMI {
960 /* syntax error '%s' */
961 error(249, "member without type");
962 $$ = NULL;
963 }
964 | begin_type_specifier_qualifier_list end_type type_attribute_opt
965 T_SEMI {
966 symtyp = FVFT;
967 if (!allow_c11 && !allow_gcc)
968 /* anonymous struct/union members is a C11 feature */
969 warning(49);
970 if (is_struct_or_union(dcs->d_type->t_tspec)) {
971 $$ = dcs->d_type->t_sou->sou_first_member;
972 /* add all the members of the anonymous struct/union */
973 anonymize($$);
974 } else {
975 /* syntax error '%s' */
976 error(249, "unnamed member");
977 $$ = NULL;
978 }
979 }
980 | static_assert_declaration {
981 $$ = NULL;
982 }
983 | error T_SEMI {
984 symtyp = FVFT;
985 $$ = NULL;
986 }
987 ;
988
989 notype_struct_declarators:
990 notype_struct_declarator {
991 $$ = declarator_1_struct_union($1);
992 }
993 | notype_struct_declarators {
994 symtyp = FMEMBER;
995 } T_COMMA type_struct_declarator {
996 $$ = concat_lists($1, declarator_1_struct_union($4));
997 }
998 ;
999
1000 type_struct_declarators:
1001 type_struct_declarator {
1002 $$ = declarator_1_struct_union($1);
1003 }
1004 | type_struct_declarators {
1005 symtyp = FMEMBER;
1006 } T_COMMA type_struct_declarator {
1007 $$ = concat_lists($1, declarator_1_struct_union($4));
1008 }
1009 ;
1010
1011 notype_struct_declarator:
1012 notype_declarator
1013 | notype_declarator T_COLON constant_expr { /* C99 6.7.2.1 */
1014 $$ = set_bit_field_width($1, to_int_constant($3, true));
1015 }
1016 | {
1017 symtyp = FVFT;
1018 } T_COLON constant_expr { /* C99 6.7.2.1 */
1019 $$ = set_bit_field_width(NULL, to_int_constant($3, true));
1020 }
1021 ;
1022
1023 type_struct_declarator:
1024 type_declarator
1025 | type_declarator T_COLON constant_expr {
1026 $$ = set_bit_field_width($1, to_int_constant($3, true));
1027 }
1028 | {
1029 symtyp = FVFT;
1030 } T_COLON constant_expr {
1031 $$ = set_bit_field_width(NULL, to_int_constant($3, true));
1032 }
1033 ;
1034
1035 /* K&R ---, C90 6.5.2.2, C99 6.7.2.2, C11 6.7.2.2 */
1036 enum_specifier: /* C99 6.7.2.2 */
1037 enum gcc_attribute_specifier_list_opt identifier_sym {
1038 $$ = make_tag_type($3, ENUM, false, false);
1039 }
1040 | enum gcc_attribute_specifier_list_opt identifier_sym {
1041 dcs->d_tagtyp = make_tag_type($3, ENUM, true, false);
1042 } enum_declaration /*gcc_attribute_specifier_list_opt*/ {
1043 $$ = complete_tag_enum(dcs->d_tagtyp, $5);
1044 }
1045 | enum gcc_attribute_specifier_list_opt {
1046 dcs->d_tagtyp = make_tag_type(NULL, ENUM, true, false);
1047 } enum_declaration /*gcc_attribute_specifier_list_opt*/ {
1048 $$ = complete_tag_enum(dcs->d_tagtyp, $4);
1049 }
1050 | enum error {
1051 symtyp = FVFT;
1052 $$ = gettyp(INT);
1053 }
1054 ;
1055
1056 enum: /* helper for C99 6.7.2.2 */
1057 T_ENUM {
1058 symtyp = FTAG;
1059 begin_declaration_level(DK_ENUM_CONSTANT);
1060 }
1061 ;
1062
1063 enum_declaration: /* helper for C99 6.7.2.2 */
1064 enum_decl_lbrace enums_with_opt_comma T_RBRACE {
1065 $$ = $2;
1066 }
1067 ;
1068
1069 enum_decl_lbrace: /* helper for C99 6.7.2.2 */
1070 T_LBRACE {
1071 symtyp = FVFT;
1072 enumval = 0;
1073 }
1074 ;
1075
1076 enums_with_opt_comma: /* helper for C99 6.7.2.2 */
1077 enumerator_list
1078 | enumerator_list T_COMMA {
1079 if (!allow_c99 && !allow_trad) {
1080 /* trailing ',' prohibited in enum declaration */
1081 error(54);
1082 } else {
1083 /* trailing ',' prohibited in enum declaration */
1084 c99ism(54);
1085 }
1086 $$ = $1;
1087 }
1088 ;
1089
1090 enumerator_list: /* C99 6.7.2.2 */
1091 enumerator
1092 | enumerator_list T_COMMA enumerator {
1093 $$ = concat_lists($1, $3);
1094 }
1095 | error {
1096 $$ = NULL;
1097 }
1098 ;
1099
1100 enumerator: /* C99 6.7.2.2 */
1101 identifier_sym gcc_attribute_specifier_list_opt {
1102 $$ = enumeration_constant($1, enumval, true);
1103 }
1104 | identifier_sym gcc_attribute_specifier_list_opt
1105 T_ASSIGN constant_expr {
1106 $$ = enumeration_constant($1, to_int_constant($4, true),
1107 false);
1108 }
1109 ;
1110
1111 type_qualifier: /* C99 6.7.3 */
1112 T_QUAL
1113 | atomic {
1114 $$ = ATOMIC;
1115 }
1116 ;
1117
1118 atomic: /* helper */
1119 T_ATOMIC {
1120 /* TODO: First fix c11ism, then use it here. */
1121 if (!allow_c11)
1122 /* '_Atomic' requires C11 or later */
1123 error(350);
1124 }
1125 ;
1126
1127 pointer: /* C99 6.7.5 */
1128 asterisk type_qualifier_list_opt {
1129 $$ = merge_qualified_pointer($1, $2);
1130 }
1131 | asterisk type_qualifier_list_opt pointer {
1132 $$ = merge_qualified_pointer($1, $2);
1133 $$ = merge_qualified_pointer($$, $3);
1134 }
1135 ;
1136
1137 asterisk: /* helper for 'pointer' */
1138 T_ASTERISK {
1139 $$ = xcalloc(1, sizeof(*$$));
1140 $$->p_pointer = true;
1141 }
1142 ;
1143
1144 type_qualifier_list_opt: /* see C99 6.7.5 */
1145 /* empty */ {
1146 $$ = NULL;
1147 }
1148 | type_qualifier_list
1149 ;
1150
1151 type_qualifier_list: /* C99 6.7.5 */
1152 type_qualifier_list_elem
1153 | type_qualifier_list type_qualifier_list_elem {
1154 $$ = merge_qualified_pointer($1, $2);
1155 }
1156 ;
1157
1158 type_qualifier_list_elem: /* helper for 'pointer' */
1159 type_qualifier {
1160 $$ = xcalloc(1, sizeof(*$$));
1161 if ($1 == CONST)
1162 $$->p_const = true;
1163 if ($1 == VOLATILE)
1164 $$->p_volatile = true;
1165 }
1166 ;
1167
1168 /*
1169 * For an explanation of 'notype' in the following rules, see
1170 * https://www.gnu.org/software/bison/manual/bison.html#Semantic-Tokens.
1171 */
1172
1173 notype_init_declarators:
1174 notype_init_declarator
1175 | notype_init_declarators T_COMMA type_init_declarator
1176 ;
1177
1178 type_init_declarators:
1179 type_init_declarator
1180 | type_init_declarators T_COMMA type_init_declarator
1181 ;
1182
1183 notype_init_declarator:
1184 notype_declarator asm_or_symbolrename_opt {
1185 cgram_declare($1, false, $2);
1186 check_size($1);
1187 }
1188 | notype_declarator asm_or_symbolrename_opt {
1189 begin_initialization($1);
1190 cgram_declare($1, true, $2);
1191 } T_ASSIGN initializer {
1192 check_size($1);
1193 end_initialization();
1194 }
1195 ;
1196
1197 type_init_declarator:
1198 type_declarator asm_or_symbolrename_opt {
1199 cgram_declare($1, false, $2);
1200 check_size($1);
1201 }
1202 | type_declarator asm_or_symbolrename_opt {
1203 begin_initialization($1);
1204 cgram_declare($1, true, $2);
1205 } T_ASSIGN initializer {
1206 check_size($1);
1207 end_initialization();
1208 }
1209 ;
1210
1211 notype_declarator:
1212 notype_direct_declarator
1213 | pointer notype_direct_declarator {
1214 $$ = add_pointer($2, $1);
1215 }
1216 ;
1217
1218 type_declarator:
1219 type_direct_declarator
1220 | pointer type_direct_declarator {
1221 $$ = add_pointer($2, $1);
1222 }
1223 ;
1224
1225 notype_direct_declarator:
1226 type_attribute_list_opt T_NAME {
1227 $$ = declarator_name(getsym($2));
1228 }
1229 | type_attribute_list_opt T_LPAREN type_declarator T_RPAREN {
1230 $$ = $3;
1231 }
1232 | notype_direct_declarator T_LBRACK array_size_opt T_RBRACK {
1233 $$ = add_array($1, $3.has_dim, $3.dim);
1234 }
1235 | notype_direct_declarator param_list asm_or_symbolrename_opt {
1236 $$ = add_function(symbolrename($1, $3), $2);
1237 end_declaration_level();
1238 block_level--;
1239 }
1240 | notype_direct_declarator type_attribute
1241 ;
1242
1243 type_direct_declarator:
1244 type_attribute_list_opt identifier {
1245 $$ = declarator_name(getsym($2));
1246 }
1247 | type_attribute_list_opt T_LPAREN type_declarator T_RPAREN {
1248 $$ = $3;
1249 }
1250 | type_direct_declarator T_LBRACK array_size_opt T_RBRACK {
1251 $$ = add_array($1, $3.has_dim, $3.dim);
1252 }
1253 | type_direct_declarator param_list asm_or_symbolrename_opt {
1254 $$ = add_function(symbolrename($1, $3), $2);
1255 end_declaration_level();
1256 block_level--;
1257 }
1258 | type_direct_declarator type_attribute
1259 ;
1260
1261 /*
1262 * The two distinct rules type_param_declarator and notype_param_declarator
1263 * avoid a conflict in argument lists. A typename enclosed in parentheses is
1264 * always treated as a typename, not an argument name. For example, after
1265 * "typedef double a;", the declaration "f(int (a));" is interpreted as
1266 * "f(int (double));", not "f(int a);".
1267 */
1268 type_param_declarator:
1269 direct_param_declarator
1270 | pointer direct_param_declarator {
1271 $$ = add_pointer($2, $1);
1272 }
1273 ;
1274
1275 notype_param_declarator:
1276 direct_notype_param_declarator
1277 | pointer direct_notype_param_declarator {
1278 $$ = add_pointer($2, $1);
1279 }
1280 ;
1281
1282 direct_param_declarator:
1283 identifier type_attribute_list {
1284 $$ = declarator_name(getsym($1));
1285 }
1286 | identifier {
1287 $$ = declarator_name(getsym($1));
1288 }
1289 | T_LPAREN notype_param_declarator T_RPAREN {
1290 $$ = $2;
1291 }
1292 | direct_param_declarator T_LBRACK array_size_opt T_RBRACK
1293 gcc_attribute_specifier_list_opt {
1294 $$ = add_array($1, $3.has_dim, $3.dim);
1295 }
1296 | direct_param_declarator param_list asm_or_symbolrename_opt {
1297 $$ = add_function(symbolrename($1, $3), $2);
1298 end_declaration_level();
1299 block_level--;
1300 }
1301 ;
1302
1303 direct_notype_param_declarator:
1304 identifier {
1305 $$ = declarator_name(getsym($1));
1306 }
1307 | T_LPAREN notype_param_declarator T_RPAREN {
1308 $$ = $2;
1309 }
1310 | direct_notype_param_declarator T_LBRACK array_size_opt T_RBRACK {
1311 $$ = add_array($1, $3.has_dim, $3.dim);
1312 }
1313 | direct_notype_param_declarator param_list asm_or_symbolrename_opt {
1314 $$ = add_function(symbolrename($1, $3), $2);
1315 end_declaration_level();
1316 block_level--;
1317 }
1318 ;
1319
1320 param_list:
1321 id_list_lparen identifier_list T_RPAREN {
1322 $$ = $2;
1323 }
1324 | abstract_decl_param_list
1325 ;
1326
1327 id_list_lparen:
1328 T_LPAREN {
1329 block_level++;
1330 begin_declaration_level(DK_PROTO_ARG);
1331 }
1332 ;
1333
1334 array_size_opt:
1335 /* empty */ {
1336 $$.has_dim = false;
1337 $$.dim = 0;
1338 }
1339 | T_ASTERISK {
1340 /* since C99; variable length array of unspecified size */
1341 $$.has_dim = false; /* TODO: maybe change to true */
1342 $$.dim = 0; /* just as a placeholder */
1343 }
1344 | array_size {
1345 $$.has_dim = true;
1346 $$.dim = $1 == NULL ? 0 : to_int_constant($1, false);
1347 }
1348 ;
1349
1350 array_size:
1351 type_qualifier_list_opt T_SCLASS constant_expr {
1352 /* C11 6.7.6.3p7 */
1353 if ($2 != STATIC)
1354 yyerror("Bad attribute");
1355 /* static array size is a C11 extension */
1356 c11ism(343);
1357 $$ = $3;
1358 }
1359 | type_qualifier {
1360 /* C11 6.7.6.2 */
1361 if ($1 != RESTRICT)
1362 yyerror("Bad attribute");
1363 $$ = NULL;
1364 }
1365 | constant_expr
1366 ;
1367
1368 identifier_list: /* C99 6.7.5 */
1369 T_NAME {
1370 $$ = old_style_function_name(getsym($1));
1371 }
1372 | identifier_list T_COMMA T_NAME {
1373 $$ = concat_lists($1, old_style_function_name(getsym($3)));
1374 }
1375 | identifier_list error
1376 ;
1377
1378 /* XXX: C99 requires an additional specifier-qualifier-list. */
1379 type_name: /* C99 6.7.6 */
1380 {
1381 begin_declaration_level(DK_ABSTRACT);
1382 } abstract_declaration {
1383 end_declaration_level();
1384 $$ = $2->s_type;
1385 }
1386 ;
1387
1388 abstract_declaration: /* specific to lint */
1389 begin_type_qualifier_list end_type {
1390 $$ = declare_1_abstract(abstract_name());
1391 }
1392 | begin_type_specifier_qualifier_list end_type {
1393 $$ = declare_1_abstract(abstract_name());
1394 }
1395 | begin_type_qualifier_list end_type abstract_declarator {
1396 $$ = declare_1_abstract($3);
1397 }
1398 | begin_type_specifier_qualifier_list end_type abstract_declarator {
1399 $$ = declare_1_abstract($3);
1400 }
1401 ;
1402
1403 /* K&R 8.7, C90 ???, C99 6.7.6, C11 6.7.7 */
1404 /* In K&R, abstract-declarator could be empty and was still simpler. */
1405 abstract_declarator:
1406 pointer {
1407 $$ = add_pointer(abstract_name(), $1);
1408 }
1409 | direct_abstract_declarator
1410 | pointer direct_abstract_declarator {
1411 $$ = add_pointer($2, $1);
1412 }
1413 | type_attribute_list direct_abstract_declarator {
1414 $$ = $2;
1415 }
1416 | pointer type_attribute_list direct_abstract_declarator {
1417 $$ = add_pointer($3, $1);
1418 }
1419 ;
1420
1421 /* K&R ---, C90 ???, C99 6.7.6, C11 6.7.7 */
1422 direct_abstract_declarator:
1423 /* TODO: sort rules according to C99 */
1424 T_LPAREN abstract_declarator T_RPAREN {
1425 $$ = $2;
1426 }
1427 | T_LBRACK array_size_opt T_RBRACK {
1428 $$ = add_array(abstract_name(), $2.has_dim, $2.dim);
1429 }
1430 | direct_abstract_declarator T_LBRACK array_size_opt T_RBRACK {
1431 $$ = add_array($1, $3.has_dim, $3.dim);
1432 }
1433 | abstract_decl_param_list asm_or_symbolrename_opt {
1434 $$ = add_function(symbolrename(abstract_name(), $2), $1);
1435 end_declaration_level();
1436 block_level--;
1437 }
1438 | direct_abstract_declarator abstract_decl_param_list
1439 asm_or_symbolrename_opt {
1440 $$ = add_function(symbolrename($1, $3), $2);
1441 end_declaration_level();
1442 block_level--;
1443 }
1444 | direct_abstract_declarator type_attribute_list
1445 ;
1446
1447 abstract_decl_param_list: /* specific to lint */
1448 abstract_decl_lparen T_RPAREN type_attribute_opt {
1449 $$ = NULL;
1450 }
1451 | abstract_decl_lparen vararg_parameter_type_list T_RPAREN
1452 type_attribute_opt {
1453 dcs->d_proto = true;
1454 $$ = $2;
1455 }
1456 | abstract_decl_lparen error T_RPAREN type_attribute_opt {
1457 $$ = NULL;
1458 }
1459 ;
1460
1461 abstract_decl_lparen: /* specific to lint */
1462 T_LPAREN {
1463 block_level++;
1464 begin_declaration_level(DK_PROTO_ARG);
1465 }
1466 ;
1467
1468 vararg_parameter_type_list: /* specific to lint */
1469 parameter_type_list
1470 | parameter_type_list T_COMMA T_ELLIPSIS {
1471 dcs->d_vararg = true;
1472 $$ = $1;
1473 }
1474 | T_ELLIPSIS {
1475 /* TODO: C99 6.7.5 makes this an error as well. */
1476 if (!allow_trad && !allow_c99) {
1477 /* ANSI C requires formal parameter before '...' */
1478 error(84);
1479 } else if (allow_c90) {
1480 /* ANSI C requires formal parameter before '...' */
1481 warning(84);
1482 }
1483 dcs->d_vararg = true;
1484 $$ = NULL;
1485 }
1486 ;
1487
1488 /* XXX: C99 6.7.5 defines the same name, but it looks different. */
1489 parameter_type_list:
1490 parameter_declaration
1491 | parameter_type_list T_COMMA parameter_declaration {
1492 $$ = concat_lists($1, $3);
1493 }
1494 ;
1495
1496 /* XXX: C99 6.7.5 defines the same name, but it looks completely different. */
1497 parameter_declaration:
1498 begin_type_declmods end_type {
1499 /* ^^ There is no check for the missing type-specifier. */
1500 $$ = declare_argument(abstract_name(), false);
1501 }
1502 | begin_type_declaration_specifiers end_type {
1503 $$ = declare_argument(abstract_name(), false);
1504 }
1505 | begin_type_declmods end_type notype_param_declarator {
1506 /* ^^ There is no check for the missing type-specifier. */
1507 $$ = declare_argument($3, false);
1508 }
1509 /*
1510 * type_param_declarator is needed because of following conflict:
1511 * "typedef int a; f(int (a));" could be parsed as
1512 * "function with argument a of type int", or
1513 * "function with an abstract argument of type function".
1514 * This grammar realizes the second case.
1515 */
1516 | begin_type_declaration_specifiers end_type type_param_declarator {
1517 $$ = declare_argument($3, false);
1518 }
1519 | begin_type_declmods end_type abstract_declarator {
1520 /* ^^ There is no check for the missing type-specifier. */
1521 $$ = declare_argument($3, false);
1522 }
1523 | begin_type_declaration_specifiers end_type abstract_declarator {
1524 $$ = declare_argument($3, false);
1525 }
1526 ;
1527
1528 initializer: /* C99 6.7.8 "Initialization" */
1529 assignment_expression {
1530 init_expr($1);
1531 }
1532 | init_lbrace init_rbrace {
1533 /* XXX: Empty braces are not covered by C99 6.7.8. */
1534 }
1535 | init_lbrace initializer_list comma_opt init_rbrace
1536 /* XXX: What is this error handling for? */
1537 | error
1538 ;
1539
1540 initializer_list: /* C99 6.7.8 "Initialization" */
1541 initializer_list_item
1542 | initializer_list T_COMMA initializer_list_item
1543 ;
1544
1545 initializer_list_item: /* helper */
1546 designation initializer
1547 | initializer
1548 ;
1549
1550 designation: /* C99 6.7.8 "Initialization" */
1551 begin_designation designator_list T_ASSIGN
1552 | identifier T_COLON {
1553 /* GCC style struct or union member name in initializer */
1554 gnuism(315);
1555 begin_designation();
1556 add_designator_member($1);
1557 }
1558 ;
1559
1560 begin_designation: /* lint-specific helper */
1561 /* empty */ {
1562 begin_designation();
1563 }
1564 ;
1565
1566 designator_list: /* C99 6.7.8 "Initialization" */
1567 designator
1568 | designator_list designator
1569 ;
1570
1571 designator: /* C99 6.7.8 "Initialization" */
1572 T_LBRACK range T_RBRACK {
1573 if (!allow_c99)
1574 /* array initializer with designators is a C99 ... */
1575 warning(321);
1576 add_designator_subscript($2);
1577 }
1578 | T_POINT identifier {
1579 if (!allow_c99)
1580 /* struct or union member name in initializer is ... */
1581 warning(313);
1582 add_designator_member($2);
1583 }
1584 ;
1585
1586 static_assert_declaration:
1587 T_STATIC_ASSERT T_LPAREN constant_expr T_COMMA T_STRING T_RPAREN T_SEMI /* C11 */
1588 | T_STATIC_ASSERT T_LPAREN constant_expr T_RPAREN T_SEMI /* C23 */
1589 ;
1590
1591 range:
1592 constant_expr {
1593 $$.lo = to_int_constant($1, true);
1594 $$.hi = $$.lo;
1595 }
1596 | constant_expr T_ELLIPSIS constant_expr {
1597 $$.lo = to_int_constant($1, true);
1598 $$.hi = to_int_constant($3, true);
1599 /* initialization with '[a...b]' is a GCC extension */
1600 gnuism(340);
1601 }
1602 ;
1603
1604 init_lbrace: /* helper */
1605 T_LBRACE {
1606 init_lbrace();
1607 }
1608 ;
1609
1610 init_rbrace: /* helper */
1611 T_RBRACE {
1612 init_rbrace();
1613 }
1614 ;
1615
1616 asm_or_symbolrename_opt: /* GCC extensions */
1617 /* empty */ {
1618 $$ = NULL;
1619 }
1620 | T_ASM T_LPAREN T_STRING T_RPAREN gcc_attribute_specifier_list_opt {
1621 freeyyv(&$3, T_STRING);
1622 $$ = NULL;
1623 }
1624 | T_SYMBOLRENAME T_LPAREN T_NAME T_RPAREN
1625 gcc_attribute_specifier_list_opt {
1626 $$ = $3;
1627 }
1628 ;
1629
1630 statement: /* C99 6.8 */
1631 expression_statement
1632 | non_expr_statement
1633 ;
1634
1635 non_expr_statement: /* helper for C99 6.8 */
1636 gcc_attribute_specifier /* ((__fallthrough__)) */ T_SEMI
1637 | labeled_statement
1638 | compound_statement
1639 | selection_statement
1640 | iteration_statement
1641 | jump_statement {
1642 seen_fallthrough = false;
1643 }
1644 | asm_statement
1645 ;
1646
1647 labeled_statement: /* C99 6.8.1 */
1648 label gcc_attribute_specifier_list_opt statement
1649 ;
1650
1651 label:
1652 T_NAME T_COLON {
1653 symtyp = FLABEL;
1654 named_label(getsym($1));
1655 }
1656 | T_CASE constant_expr T_COLON {
1657 case_label($2);
1658 seen_fallthrough = true;
1659 }
1660 | T_CASE constant_expr T_ELLIPSIS constant_expr T_COLON {
1661 /* XXX: We don't fill all cases */
1662 case_label($2);
1663 seen_fallthrough = true;
1664 }
1665 | T_DEFAULT T_COLON {
1666 default_label();
1667 seen_fallthrough = true;
1668 }
1669 ;
1670
1671 compound_statement: /* C99 6.8.2 */
1672 compound_statement_lbrace compound_statement_rbrace
1673 | compound_statement_lbrace block_item_list compound_statement_rbrace
1674 ;
1675
1676 compound_statement_lbrace:
1677 T_LBRACE {
1678 block_level++;
1679 mem_block_level++;
1680 begin_declaration_level(DK_AUTO);
1681 }
1682 ;
1683
1684 compound_statement_rbrace:
1685 T_RBRACE {
1686 end_declaration_level();
1687 level_free_all(mem_block_level);
1688 mem_block_level--;
1689 block_level--;
1690 seen_fallthrough = false;
1691 }
1692 ;
1693
1694 block_item_list: /* C99 6.8.2 */
1695 block_item
1696 | block_item_list block_item {
1697 if ($1 && !$2)
1698 /* declarations after statements is a C99 feature */
1699 c99ism(327);
1700 $$ = $1 || $2;
1701 }
1702 ;
1703
1704 block_item: /* C99 6.8.2 */
1705 declaration_or_error {
1706 $$ = false;
1707 restore_warning_flags();
1708 }
1709 | statement {
1710 $$ = true;
1711 restore_warning_flags();
1712 }
1713 ;
1714
1715 expression_statement: /* C99 6.8.3 */
1716 expression T_SEMI {
1717 expr($1, false, false, false, false);
1718 seen_fallthrough = false;
1719 }
1720 | T_SEMI {
1721 check_statement_reachable();
1722 seen_fallthrough = false;
1723 }
1724 ;
1725
1726 selection_statement: /* C99 6.8.4 */
1727 if_without_else %prec T_THEN {
1728 save_warning_flags();
1729 if2();
1730 if3(false);
1731 }
1732 | if_without_else T_ELSE {
1733 save_warning_flags();
1734 if2();
1735 } statement {
1736 clear_warning_flags();
1737 if3(true);
1738 }
1739 | if_without_else T_ELSE error {
1740 clear_warning_flags();
1741 if3(false);
1742 }
1743 | switch_expr statement {
1744 clear_warning_flags();
1745 switch2();
1746 }
1747 | switch_expr error {
1748 clear_warning_flags();
1749 switch2();
1750 }
1751 ;
1752
1753 if_without_else: /* see C99 6.8.4 */
1754 if_expr statement
1755 | if_expr error
1756 ;
1757
1758 if_expr: /* see C99 6.8.4 */
1759 T_IF T_LPAREN expression T_RPAREN {
1760 if1($3);
1761 clear_warning_flags();
1762 }
1763 ;
1764
1765 switch_expr: /* see C99 6.8.4 */
1766 T_SWITCH T_LPAREN expression T_RPAREN {
1767 switch1($3);
1768 clear_warning_flags();
1769 }
1770 ;
1771
1772 iteration_statement: /* C99 6.8.5 */
1773 while_expr statement {
1774 clear_warning_flags();
1775 while2();
1776 }
1777 | while_expr error {
1778 clear_warning_flags();
1779 while2();
1780 }
1781 | do_statement do_while_expr {
1782 do2($2);
1783 seen_fallthrough = false;
1784 }
1785 | do error {
1786 clear_warning_flags();
1787 do2(NULL);
1788 }
1789 | for_exprs statement {
1790 clear_warning_flags();
1791 for2();
1792 end_declaration_level();
1793 block_level--;
1794 }
1795 | for_exprs error {
1796 clear_warning_flags();
1797 for2();
1798 end_declaration_level();
1799 block_level--;
1800 }
1801 ;
1802
1803 while_expr: /* see C99 6.8.5 */
1804 T_WHILE T_LPAREN expression T_RPAREN {
1805 while1($3);
1806 clear_warning_flags();
1807 }
1808 ;
1809
1810 do_statement: /* see C99 6.8.5 */
1811 do statement {
1812 clear_warning_flags();
1813 }
1814 ;
1815
1816 do: /* see C99 6.8.5 */
1817 T_DO {
1818 do1();
1819 }
1820 ;
1821
1822 do_while_expr: /* see C99 6.8.5 */
1823 T_WHILE T_LPAREN expression T_RPAREN T_SEMI {
1824 $$ = $3;
1825 }
1826 ;
1827
1828 for_start: /* see C99 6.8.5 */
1829 T_FOR T_LPAREN {
1830 begin_declaration_level(DK_AUTO);
1831 block_level++;
1832 }
1833 ;
1834
1835 for_exprs: /* see C99 6.8.5 */
1836 for_start
1837 begin_type_declaration_specifiers end_type
1838 notype_init_declarators T_SEMI
1839 expression_opt T_SEMI
1840 expression_opt T_RPAREN {
1841 /* variable declaration in for loop */
1842 c99ism(325);
1843 for1(NULL, $6, $8);
1844 clear_warning_flags();
1845 }
1846 | for_start
1847 expression_opt T_SEMI
1848 expression_opt T_SEMI
1849 expression_opt T_RPAREN {
1850 for1($2, $4, $6);
1851 clear_warning_flags();
1852 }
1853 ;
1854
1855 jump_statement: /* C99 6.8.6 */
1856 goto identifier T_SEMI {
1857 do_goto(getsym($2));
1858 }
1859 | goto error T_SEMI {
1860 symtyp = FVFT;
1861 }
1862 | T_CONTINUE T_SEMI {
1863 do_continue();
1864 }
1865 | T_BREAK T_SEMI {
1866 do_break();
1867 }
1868 | T_RETURN sys T_SEMI {
1869 do_return($2, NULL);
1870 }
1871 | T_RETURN sys expression T_SEMI {
1872 do_return($2, $3);
1873 }
1874 ;
1875
1876 goto: /* see C99 6.8.6 */
1877 T_GOTO {
1878 symtyp = FLABEL;
1879 }
1880 ;
1881
1882 asm_statement: /* GCC extension */
1883 T_ASM T_LPAREN read_until_rparen T_SEMI {
1884 dcs_set_asm();
1885 }
1886 | T_ASM type_qualifier T_LPAREN read_until_rparen T_SEMI {
1887 dcs_set_asm();
1888 }
1889 | T_ASM error
1890 ;
1891
1892 read_until_rparen: /* helper for 'asm_statement' */
1893 /* empty */ {
1894 read_until_rparen();
1895 }
1896 ;
1897
1898 translation_unit: /* C99 6.9 */
1899 external_declaration
1900 | translation_unit external_declaration
1901 ;
1902
1903 external_declaration: /* C99 6.9 */
1904 function_definition {
1905 global_clean_up_decl(false);
1906 clear_warning_flags();
1907 }
1908 | top_level_declaration {
1909 global_clean_up_decl(false);
1910 clear_warning_flags();
1911 }
1912 | asm_statement /* GCC extension */
1913 | T_SEMI { /* GCC extension */
1914 /*
1915 * TODO: Only allow this in GCC mode, not in plain C99.
1916 * This is one of the top 10 warnings in the NetBSD build.
1917 */
1918 if (!allow_trad && !allow_c99) {
1919 /* empty declaration */
1920 error(0);
1921 } else if (allow_c90) {
1922 /* empty declaration */
1923 warning(0);
1924 }
1925 }
1926 ;
1927
1928 /*
1929 * On the top level, lint allows several forms of declarations that it doesn't
1930 * allow in functions. For example, a single ';' is an empty declaration and
1931 * is supported by some compilers, but in a function it would be an empty
1932 * statement, not a declaration. This makes a difference in C90 mode, where
1933 * a statement must not be followed by a declaration.
1934 *
1935 * See 'declaration' for all other declarations.
1936 */
1937 top_level_declaration: /* C99 6.9 calls this 'declaration' */
1938 begin_type end_type notype_init_declarators T_SEMI {
1939 /* TODO: Make this an error in C99 mode as well. */
1940 if (!allow_trad && !allow_c99) {
1941 /* old-style declaration; add 'int' */
1942 error(1);
1943 } else if (allow_c90) {
1944 /* old-style declaration; add 'int' */
1945 warning(1);
1946 }
1947 }
1948 | declaration
1949 | error T_SEMI {
1950 global_clean_up();
1951 }
1952 | error T_RBRACE {
1953 global_clean_up();
1954 }
1955 ;
1956
1957 function_definition: /* C99 6.9.1 */
1958 func_declarator {
1959 if ($1->s_type->t_tspec != FUNC) {
1960 /* syntax error '%s' */
1961 error(249, yytext);
1962 YYERROR;
1963 }
1964 if ($1->s_type->t_typedef) {
1965 /* ()-less function definition */
1966 error(64);
1967 YYERROR;
1968 }
1969 begin_function($1);
1970 block_level++;
1971 begin_declaration_level(DK_OLD_STYLE_ARG);
1972 if (lwarn == LWARN_NONE)
1973 $1->s_used = true;
1974 } arg_declaration_list_opt {
1975 end_declaration_level();
1976 block_level--;
1977 check_func_lint_directives();
1978 check_func_old_style_arguments();
1979 begin_control_statement(CS_FUNCTION_BODY);
1980 } compound_statement {
1981 end_function();
1982 end_control_statement(CS_FUNCTION_BODY);
1983 }
1984 ;
1985
1986 func_declarator:
1987 begin_type end_type notype_declarator {
1988 if (!allow_trad) {
1989 /* old-style declaration; add 'int' */
1990 error(1);
1991 }
1992 $$ = $3;
1993 }
1994 | begin_type_declmods end_type notype_declarator {
1995 if (!allow_trad) {
1996 /* old-style declaration; add 'int' */
1997 error(1);
1998 }
1999 $$ = $3;
2000 }
2001 | begin_type_declaration_specifiers end_type type_declarator {
2002 $$ = $3;
2003 }
2004 ;
2005
2006 arg_declaration_list_opt: /* C99 6.9.1p13 example 1 */
2007 /* empty */
2008 | arg_declaration_list
2009 ;
2010
2011 arg_declaration_list: /* C99 6.9.1p13 example 1 */
2012 arg_declaration
2013 | arg_declaration_list arg_declaration
2014 /* XXX or better "arg_declaration error" ? */
2015 | error
2016 ;
2017
2018 /*
2019 * "arg_declaration" is separated from "declaration" because it
2020 * needs other error handling.
2021 */
2022 arg_declaration:
2023 begin_type_declmods end_type T_SEMI {
2024 /* empty declaration */
2025 warning(2);
2026 }
2027 | begin_type_declmods end_type notype_init_declarators T_SEMI
2028 | begin_type_declaration_specifiers end_type T_SEMI {
2029 if (!dcs->d_nonempty_decl) {
2030 /* empty declaration */
2031 warning(2);
2032 } else {
2033 /* '%s' declared in argument declaration list */
2034 warning(3, type_name(dcs->d_type));
2035 }
2036 }
2037 | begin_type_declaration_specifiers end_type
2038 type_init_declarators T_SEMI {
2039 if (dcs->d_nonempty_decl) {
2040 /* '%s' declared in argument declaration list */
2041 warning(3, type_name(dcs->d_type));
2042 }
2043 }
2044 | begin_type_declmods error
2045 | begin_type_declaration_specifiers error
2046 ;
2047
2048 /* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html */
2049 gcc_attribute_specifier_list_opt:
2050 /* empty */
2051 | gcc_attribute_specifier_list
2052 ;
2053
2054 gcc_attribute_specifier_list:
2055 gcc_attribute_specifier
2056 | gcc_attribute_specifier_list gcc_attribute_specifier
2057 ;
2058
2059 gcc_attribute_specifier:
2060 T_ATTRIBUTE T_LPAREN T_LPAREN {
2061 in_gcc_attribute = true;
2062 } gcc_attribute_list {
2063 in_gcc_attribute = false;
2064 } T_RPAREN T_RPAREN
2065 ;
2066
2067 gcc_attribute_list:
2068 gcc_attribute
2069 | gcc_attribute_list T_COMMA gcc_attribute
2070 ;
2071
2072 gcc_attribute:
2073 /* empty */
2074 | T_NAME {
2075 const char *name = $1->sb_name;
2076 if (is_either(name, "packed", "__packed__"))
2077 dcs_add_packed();
2078 else if (is_either(name, "used", "__used__") ||
2079 is_either(name, "unused", "__unused__"))
2080 dcs_set_used();
2081 else if (is_either(name, "fallthrough", "__fallthrough__"))
2082 fallthru(1);
2083 }
2084 | T_NAME T_LPAREN T_RPAREN
2085 | T_NAME T_LPAREN gcc_attribute_parameters T_RPAREN
2086 | type_qualifier {
2087 if ($1 != CONST)
2088 yyerror("Bad attribute");
2089 }
2090 ;
2091
2092 gcc_attribute_parameters:
2093 constant_expr
2094 | gcc_attribute_parameters T_COMMA constant_expr
2095 ;
2096
2097 sys:
2098 /* empty */ {
2099 $$ = in_system_header;
2100 }
2101 ;
2102
2103 %%
2104
2105 /* ARGSUSED */
2106 int
2107 yyerror(const char *msg)
2108 {
2109 /* syntax error '%s' */
2110 error(249, yytext);
2111 if (++sytxerr >= 5)
2112 norecover();
2113 return 0;
2114 }
2115
2116 #if YYDEBUG && (YYBYACC || YYBISON)
2117 static const char *
2118 cgram_to_string(int token, YYSTYPE val)
2119 {
2120
2121 switch (token) {
2122 case T_INCDEC:
2123 case T_MULTIPLICATIVE:
2124 case T_ADDITIVE:
2125 case T_SHIFT:
2126 case T_RELATIONAL:
2127 case T_EQUALITY:
2128 case T_OPASSIGN:
2129 return modtab[val.y_op].m_name;
2130 case T_SCLASS:
2131 return scl_name(val.y_scl);
2132 case T_TYPE:
2133 case T_STRUCT_OR_UNION:
2134 return tspec_name(val.y_tspec);
2135 case T_QUAL:
2136 return tqual_name(val.y_tqual);
2137 case T_NAME:
2138 return val.y_name->sb_name;
2139 default:
2140 return "<none>";
2141 }
2142 }
2143 #endif
2144
2145 #if YYDEBUG && YYBISON
2146 static inline void
2147 cgram_print(FILE *output, int token, YYSTYPE val)
2148 {
2149 (void)fprintf(output, "%s", cgram_to_string(token, val));
2150 }
2151 #endif
2152
2153 static void
2154 cgram_declare(sym_t *decl, bool initflg, sbuf_t *renaming)
2155 {
2156 declare(decl, initflg, renaming);
2157 if (renaming != NULL)
2158 freeyyv(&renaming, T_NAME);
2159 }
2160
2161 /*
2162 * Discard all input tokens up to and including the next
2163 * unmatched right paren
2164 */
2165 static void
2166 read_until_rparen(void)
2167 {
2168 int level;
2169
2170 if (yychar < 0)
2171 yychar = yylex();
2172 freeyyv(&yylval, yychar);
2173
2174 level = 1;
2175 while (yychar > 0) {
2176 if (yychar == T_LPAREN)
2177 level++;
2178 if (yychar == T_RPAREN && --level == 0)
2179 break;
2180 freeyyv(&yylval, yychar = yylex());
2181 }
2182
2183 yyclearin;
2184 }
2185
2186 static sym_t *
2187 symbolrename(sym_t *s, sbuf_t *sb)
2188 {
2189 if (sb != NULL)
2190 s->s_rename = sb->sb_name;
2191 return s;
2192 }
2193