xref: /netbsd-src/usr.bin/xlint/lint1/cgram.y (revision b2c35e17b976cf7ccd7250c86c6f5e95090ed636)
1 %{
2 /* $NetBSD: cgram.y,v 1.506 2024/06/17 22:11:09 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 1.506 2024/06/17 22:11:09 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 parameters 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 balanced_token_sequence read_balanced_token_sequence(void);
73 static sym_t *symbolrename(sym_t *, sbuf_t *);
74 
75 
76 /* ARGSUSED */
77 static void
78 clear_warning_flags_loc(const char *file, size_t line)
79 {
80 	debug_step("%s:%zu: clearing flags", file, line);
81 	reset_suppressions();
82 	saved_lwarn = LWARN_NOTHING_SAVED;
83 }
84 
85 /* ARGSUSED */
86 static void
87 save_warning_flags_loc(const char *file, size_t line)
88 {
89 	debug_step("%s:%zu: saving flags %d", file, line, lwarn);
90 	saved_lwarn = lwarn;
91 }
92 
93 /* ARGSUSED */
94 static void
95 restore_warning_flags_loc(const char *file, size_t line)
96 {
97 	if (saved_lwarn != LWARN_NOTHING_SAVED) {
98 		lwarn = saved_lwarn;
99 		debug_step("%s:%zu: restoring flags %d", file, line, lwarn);
100 	} else
101 		clear_warning_flags_loc(file, line);
102 }
103 
104 #define clear_warning_flags()	clear_warning_flags_loc(__FILE__, __LINE__)
105 #define save_warning_flags()	save_warning_flags_loc(__FILE__, __LINE__)
106 #define restore_warning_flags()	restore_warning_flags_loc(__FILE__, __LINE__)
107 
108 static bool
109 is_either(const char *s, const char *a, const char *b)
110 {
111 	return strcmp(s, a) == 0 || strcmp(s, b) == 0;
112 }
113 
114 static void
115 attribute_list_add(attribute_list *list, attribute attr)
116 {
117 	if (list->len >= list->cap) {
118 		attribute *old_attrs = list->attrs;
119 		list->cap = 16 + 2 * list->cap;
120 		list->attrs = block_zero_alloc(
121 		    list->cap * sizeof(*list->attrs), "attribute[]");
122 		if (list->len > 0)
123 			memcpy(list->attrs, old_attrs,
124 			    list->len * sizeof(*list->attrs));
125 	}
126 	list->attrs[list->len++] = attr;
127 }
128 
129 static void
130 attribute_list_add_all(attribute_list *dst, attribute_list src)
131 {
132 	for (size_t i = 0, n = src.len; i < n; i++)
133 		attribute_list_add(dst, src.attrs[i]);
134 }
135 
136 static attribute
137 new_attribute(const sbuf_t *prefix, const sbuf_t *name,
138 	      const balanced_token_sequence *arg)
139 {
140 	attribute attr = { .name = xstrdup(name->sb_name) };
141 	if (prefix != NULL)
142 		attr.prefix = xstrdup(prefix->sb_name);
143 	if (arg != NULL) {
144 		attr.arg = block_zero_alloc(sizeof(*attr.arg),
145 		    "balanced_token_sequence");
146 		*attr.arg = *arg;
147 	}
148 	return attr;
149 }
150 
151 #if YYDEBUG && YYBYACC
152 #define YYSTYPE_TOSTRING cgram_to_string
153 #endif
154 
155 %}
156 
157 %expect 110
158 
159 %union {
160 	val_t	*y_val;
161 	sbuf_t	*y_name;
162 	sym_t	*y_sym;
163 	bool	y_inc;
164 	op_t	y_op;
165 	scl_t	y_scl;
166 	tspec_t	y_tspec;
167 	type_qualifiers y_type_qualifiers;
168 	function_specifier y_function_specifier;
169 	parameter_list y_parameter_list;
170 	function_call *y_arguments;
171 	type_t	*y_type;
172 	tnode_t	*y_tnode;
173 	range_t	y_range;
174 	buffer	*y_string;
175 	qual_ptr *y_qual_ptr;
176 	bool	y_seen_statement;
177 	struct generic_association *y_generic;
178 	array_size y_array_size;
179 	bool	y_in_system_header;
180 	designation y_designation;
181 	named_constant y_named_constant;
182 	attribute y_attribute;
183 	attribute_list y_attribute_list;
184 	balanced_token_sequence y_tokens;
185 };
186 
187 /* for Bison:
188 %printer {
189 	if (is_integer($$->v_tspec))
190 		fprintf(yyo, "%lld", (long long)$$->u.integer);
191 	else
192 		fprintf(yyo, "%Lg", $$->u.floating);
193 } <y_val>
194 %printer { fprintf(yyo, "'%s'", $$ != NULL ? $$->sb_name : "<null>"); } <y_name>
195 %printer {
196 	bool indented = debug_push_indented(true);
197 	debug_sym("", $$, "");
198 	debug_pop_indented(indented);
199 } <y_sym>
200 %printer { fprintf(yyo, "%s", $$ ? "++" : "--"); } <y_inc>
201 %printer { fprintf(yyo, "%s", op_name($$)); } <y_op>
202 %printer { fprintf(yyo, "%s", scl_name($$)); } <y_scl>
203 %printer { fprintf(yyo, "%s", tspec_name($$)); } <y_tspec>
204 %printer { fprintf(yyo, "%s", type_qualifiers_string($$)); } <y_type_qualifiers>
205 %printer {
206 	fprintf(yyo, "%s", function_specifier_name($$));
207 } <y_function_specifier>
208 %printer {
209 	size_t n = 0;
210 	for (const sym_t *p = $$.first; p != NULL; p = p->s_next)
211 		n++;
212 	fprintf(yyo, "%zu parameter%s", n, n != 1 ? "s" : "");
213 } <y_parameter_list>
214 %printer { fprintf(yyo, "%s", type_name($$)); } <y_type>
215 %printer {
216 	if ($$ == NULL)
217 		fprintf(yyo, "<null>");
218 	else
219 		fprintf(yyo, "%s '%s'",
220 		    op_name($$->tn_op), type_name($$->tn_type));
221 } <y_tnode>
222 %printer { fprintf(yyo, "%zu to %zu", $$.lo, $$.hi); } <y_range>
223 %printer { fprintf(yyo, "length %zu", $$->len); } <y_string>
224 %printer {
225 	fprintf(yyo, "%s *", type_qualifiers_string($$->qualifiers));
226 } <y_qual_ptr>
227 %printer { fprintf(yyo, "%s", $$ ? "yes" : "no"); } <y_seen_statement>
228 %printer { fprintf(yyo, "%s", type_name($$->ga_arg)); } <y_generic>
229 %printer { fprintf(yyo, "%d", $$.dim); } <y_array_size>
230 %printer { fprintf(yyo, "%s", $$ ? "yes" : "no"); } <y_in_system_header>
231 %printer {
232 	if ($$.dn_len == 0)
233 		fprintf(yyo, "(empty)");
234 	for (size_t i = 0; i < $$.dn_len; i++) {
235 		const designator *dr = $$.dn_items + i;
236 		if (dr->dr_kind == DK_MEMBER)
237 			fprintf(yyo, ".%s", dr->dr_member->s_name);
238 		else if (dr->dr_kind == DK_SUBSCRIPT)
239 			fprintf(yyo, "[%zu]", dr->dr_subscript);
240 		else
241 			fprintf(yyo, "<scalar>");
242 	}
243 } <y_designation>
244 %printer { fprintf(yyo, "%s", named_constant_name($$)); } <y_named_constant>
245 */
246 
247 %token			T_LBRACE T_RBRACE T_LBRACK T_RBRACK T_LPAREN T_RPAREN
248 %token			T_POINT T_ARROW
249 %token			T_COMPLEMENT T_LOGNOT
250 %token	<y_inc>		T_INCDEC
251 %token			T_SIZEOF
252 %token			T_BUILTIN_OFFSETOF
253 %token			T_TYPEOF
254 %token			T_EXTENSION
255 %token			T_ALIGNAS
256 %token			T_ALIGNOF
257 %token			T_ASTERISK
258 %token	<y_op>		T_MULTIPLICATIVE
259 %token	<y_op>		T_ADDITIVE
260 %token	<y_op>		T_SHIFT
261 %token	<y_op>		T_RELATIONAL
262 %token	<y_op>		T_EQUALITY
263 %token			T_AMPER
264 %token			T_BITXOR
265 %token			T_BITOR
266 %token			T_LOGAND
267 %token			T_LOGOR
268 %token			T_QUEST
269 %token			T_COLON
270 %token			T_ASSIGN
271 %token	<y_op>		T_OPASSIGN
272 %token			T_COMMA
273 %token			T_SEMI
274 %token			T_ELLIPSIS
275 %token			T_DCOLON
276 %token			T_REAL
277 %token			T_IMAG
278 %token			T_GENERIC
279 
280 /* storage classes (extern, static, auto, register and typedef) */
281 %token	<y_scl>		T_SCLASS
282 %token	<y_function_specifier> T_FUNCTION_SPECIFIER
283 
284 /*
285  * predefined type keywords (char, int, short, long, unsigned, signed,
286  * float, double, void); see T_TYPENAME for types from typedef
287  */
288 %token	<y_tspec>	T_TYPE
289 
290 %token	<y_type_qualifiers>	T_QUAL
291 %token	<y_type_qualifiers>	T_ATOMIC
292 
293 /* struct or union */
294 %token	<y_tspec>	T_STRUCT_OR_UNION
295 
296 /* remaining keywords */
297 %token			T_ASM
298 %token			T_BREAK
299 %token			T_CASE
300 %token			T_CONTINUE
301 %token			T_DEFAULT
302 %token			T_DO
303 %token			T_ELSE
304 %token			T_ENUM
305 %token			T_FOR
306 %token			T_GOTO
307 %token			T_IF
308 %token			T_PACKED
309 %token			T_RETURN
310 %token			T_SWITCH
311 %token			T_SYMBOLRENAME
312 %token			T_WHILE
313 %token			T_STATIC_ASSERT
314 
315 %token			T_ATTRIBUTE
316 
317 %left	T_THEN
318 %left	T_ELSE
319 %right	T_QUEST T_COLON
320 %left	T_LOGOR
321 %left	T_LOGAND
322 %left	T_BITOR
323 %left	T_BITXOR
324 %left	T_AMPER
325 %left	T_EQUALITY
326 %left	T_RELATIONAL
327 %left	T_SHIFT
328 %left	T_ADDITIVE
329 %left	T_ASTERISK T_MULTIPLICATIVE
330 
331 %token	<y_name>	T_NAME
332 %token	<y_name>	T_TYPENAME
333 %token	<y_val>		T_CON
334 %token	<y_named_constant> T_NAMED_CONSTANT
335 %token	<y_string>	T_STRING
336 
337 /* No type for program. */
338 %type	<y_sym>		identifier_sym
339 %type	<y_name>	identifier
340 %type	<y_string>	string
341 %type	<y_tnode>	primary_expression
342 %type	<y_designation>	member_designator
343 %type	<y_tnode>	generic_selection
344 %type	<y_generic>	generic_assoc_list
345 %type	<y_generic>	generic_association
346 %type	<y_tnode>	postfix_expression
347 %type	<y_tnode>	gcc_statement_expr_list
348 %type	<y_tnode>	gcc_statement_expr_item
349 %type	<y_op>		point_or_arrow
350 %type	<y_arguments>	argument_expression_list
351 %type	<y_scl>		storage_class_specifiers
352 %type	<y_tnode>	unary_expression
353 %type	<y_tnode>	cast_expression
354 %type	<y_tnode>	expression_opt
355 %type	<y_tnode>	conditional_expression
356 %type	<y_tnode>	assignment_expression
357 %type	<y_tnode>	expression
358 %type	<y_tnode>	constant_expression
359 /* No type for declaration_or_error. */
360 /* No type for declaration. */
361 /* No type for begin_type_declaration_specifiers. */
362 /* No type for begin_type_declmods. */
363 /* No type for begin_type_specifier_qualifier_list. */
364 /* No type for begin_type_specifier_qualifier_list_postfix. */
365 %type	<y_type>	begin_type_typespec
366 /* No type for begin_type_qualifier_list. */
367 /* No type for declmod. */
368 /* No type for type_attribute_list_opt. */
369 /* No type for type_attribute_list. */
370 /* No type for type_attribute_opt. */
371 /* No type for type_attribute. */
372 /* No type for begin_type. */
373 /* No type for end_type. */
374 /* No type for notype_init_declarator_list. */
375 /* No type for type_init_declarator_list. */
376 /* No type for notype_init_declarator. */
377 /* No type for type_init_declarator. */
378 %type	<y_scl>		storage_class_specifier
379 %type	<y_type>	type_type_specifier
380 %type	<y_type>	notype_type_specifier
381 %type	<y_type>	struct_or_union_specifier
382 %type	<y_tspec>	struct_or_union
383 %type	<y_sym>		braced_member_declaration_list
384 %type	<y_sym>		member_declaration_list_with_rbrace
385 %type	<y_sym>		member_declaration_list
386 %type	<y_sym>		member_declaration
387 %type	<y_sym>		notype_member_declarator_list
388 %type	<y_sym>		type_member_declarator_list
389 %type	<y_sym>		notype_member_declarator
390 %type	<y_sym>		type_member_declarator
391 %type	<y_type>	enum_specifier
392 /* No type for enum. */
393 %type	<y_sym>		enum_declaration
394 %type	<y_sym>		enums_with_opt_comma
395 %type	<y_sym>		enumerator_list
396 %type	<y_sym>		enumerator
397 %type	<y_type>	atomic_type_specifier
398 /* No type for atomic. */
399 %type	<y_type_qualifiers>	type_qualifier
400 %type	<y_sym>		notype_declarator
401 %type	<y_sym>		type_declarator
402 %type	<y_sym>		notype_direct_declarator
403 %type	<y_sym>		type_direct_declarator
404 %type	<y_qual_ptr>	pointer
405 %type	<y_type_qualifiers>	type_qualifier_list_opt
406 %type	<y_type_qualifiers>	type_qualifier_list
407 %type	<y_sym>		parameter_declaration
408 %type	<y_sym>		type_param_declarator
409 %type	<y_sym>		notype_param_declarator
410 %type	<y_sym>		direct_param_declarator
411 %type	<y_sym>		direct_notype_param_declarator
412 %type	<y_parameter_list>	param_list
413 %type	<y_array_size>	array_size_opt
414 %type	<y_sym>		identifier_list
415 %type	<y_type>	type_name
416 %type	<y_sym>		abstract_declaration
417 %type	<y_parameter_list>	abstract_decl_param_list
418 /* No type for abstract_decl_lparen. */
419 %type	<y_parameter_list>	vararg_parameter_type_list
420 %type	<y_parameter_list>	parameter_type_list
421 %type	<y_sym>		abstract_declarator
422 %type	<y_sym>		direct_abstract_declarator
423 /* No type for braced_initializer. */
424 /* No type for initializer. */
425 /* No type for initializer_list. */
426 /* No type for designation. */
427 /* No type for designator_list. */
428 /* No type for designator. */
429 /* No type for static_assert_declaration. */
430 %type	<y_range>	range
431 /* No type for init_lbrace. */
432 /* No type for init_rbrace. */
433 %type	<y_attribute_list>	attribute_specifier_sequence
434 %type	<y_attribute_list>	attribute_specifier
435 %type	<y_attribute_list>	attribute_list
436 %type	<y_attribute>		attribute
437 %type	<y_tokens>		attribute_argument_clause
438 %type	<y_name>	asm_or_symbolrename_opt
439 /* No type for statement. */
440 /* No type for no_attr_statement. */
441 /* No type for non_expr_statement. */
442 /* No type for no_attr_non_expr_statement. */
443 /* No type for label. */
444 /* No type for labeled_statement. */
445 /* No type for compound_statement. */
446 /* No type for compound_statement_lbrace. */
447 /* No type for compound_statement_rbrace. */
448 %type	<y_seen_statement> block_item_list
449 %type	<y_seen_statement> block_item
450 /* No type for expression_statement. */
451 /* No type for selection_statement. */
452 /* No type for if_without_else. */
453 /* No type for if_expr. */
454 /* No type for switch_expr. */
455 /* No type for iteration_statement. */
456 /* No type for while_expr. */
457 /* No type for do_statement. */
458 /* No type for do. */
459 /* No type for for_start. */
460 /* No type for for_exprs. */
461 /* No type for jump_statement. */
462 /* No type for goto. */
463 /* No type for asm_statement. */
464 /* No type for read_until_rparen. */
465 /* No type for translation_unit. */
466 /* No type for external_declaration. */
467 /* No type for top_level_declaration. */
468 /* No type for function_definition. */
469 %type	<y_sym>		func_declarator
470 /* No type for arg_declaration_list_opt. */
471 /* No type for arg_declaration_list. */
472 /* No type for arg_declaration. */
473 /* No type for gcc_attribute_specifier_list_opt. */
474 /* No type for gcc_attribute_specifier_list. */
475 /* No type for gcc_attribute_specifier. */
476 /* No type for gcc_attribute_list. */
477 /* No type for gcc_attribute. */
478 %type	<y_in_system_header> sys
479 
480 %%
481 
482 program:
483 	/* empty */ {
484 		/* TODO: Make this an error in C99 mode as well. */
485 		if (!allow_trad && !allow_c99)
486 			/* empty translation unit */
487 			error(272);
488 		else if (allow_c90)
489 			/* empty translation unit */
490 			warning(272);
491 	}
492 |	translation_unit
493 ;
494 
495 identifier_sym:			/* helper for struct/union/enum */
496 	identifier {
497 		$$ = getsym($1);
498 	}
499 ;
500 
501 /* K&R ???, C90 ???, C99 6.4.2.1, C11 ??? */
502 identifier:
503 	T_NAME {
504 		debug_step("cgram: name '%s'", $1->sb_name);
505 		$$ = $1;
506 	}
507 |	T_TYPENAME {
508 		debug_step("cgram: typename '%s'", $1->sb_name);
509 		$$ = $1;
510 	}
511 ;
512 
513 /* see C99 6.4.5, string literals are joined by 5.1.1.2 */
514 string:
515 	T_STRING
516 |	string T_STRING {
517 		if (!allow_c90)
518 			/* concatenated strings are illegal in traditional C */
519 			warning(219);
520 		$$ = cat_strings($1, $2);
521 	}
522 ;
523 
524 /* K&R 7.1, C90 ???, C99 6.5.1, C11 6.5.1, C23 6.5.2 */
525 primary_expression:
526 	T_NAME {
527 		bool sys_name, sys_next;
528 		sys_name = in_system_header;
529 		if (yychar < 0)
530 			yychar = yylex();
531 		sys_next = in_system_header;
532 		in_system_header = sys_name;
533 		$$ = build_name(getsym($1), yychar == T_LPAREN);
534 		in_system_header = sys_next;
535 	}
536 |	T_CON {
537 		$$ = build_constant(gettyp($1->v_tspec), $1);
538 	}
539 |	T_NAMED_CONSTANT {
540 		if ($1 == NC_NULLPTR) {
541 			tnode_t *zero = expr_alloc_tnode();
542 			zero->tn_op = CON;
543 			zero->tn_type = gettyp(INT);
544 			zero->u.value.v_tspec = INT;
545 
546 			type_t *void_ptr = block_derive_type(gettyp(VOID), PTR);
547 			$$ = convert(CVT, 0, void_ptr, zero);
548 			$$->tn_sys = zero->tn_sys;
549 		} else {
550 			tnode_t *nc = expr_alloc_tnode();
551 			nc->tn_op = CON;
552 			nc->tn_type = gettyp(BOOL);
553 			nc->u.value.v_tspec = BOOL;
554 			nc->u.value.u.integer = $1 == NC_TRUE ? 1 : 0;
555 			$$ = nc;
556 		}
557 	}
558 |	string {
559 		$$ = build_string($1);
560 	}
561 |	T_LPAREN expression T_RPAREN {
562 		if ($2 != NULL)
563 			$2->tn_parenthesized = true;
564 		$$ = $2;
565 	}
566 |	generic_selection
567 	/* GCC primary-expression, see c_parser_postfix_expression */
568 |	T_BUILTIN_OFFSETOF T_LPAREN type_name T_COMMA {
569 		set_sym_kind(SK_MEMBER);
570 	} member_designator T_RPAREN {
571 		$$ = build_offsetof($3, $6);
572 	}
573 ;
574 
575 /* K&R ---, C90 ---, C99 7.17p3, C11 7.19p3, C23 7.21p4 */
576 member_designator:
577 	identifier {
578 		$$ = (designation) { .dn_len = 0 };
579 		designation_push(&$$, DK_MEMBER, getsym($1), 0);
580 	}
581 |	member_designator T_LBRACK range T_RBRACK {
582 		$$ = $1;
583 		designation_push(&$$, DK_SUBSCRIPT, NULL, $3.lo);
584 	}
585 |	member_designator T_POINT {
586 		set_sym_kind(SK_MEMBER);
587 	} identifier {
588 		$$ = $1;
589 		designation_push(&$$, DK_MEMBER, getsym($4), 0);
590 	}
591 ;
592 
593 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */
594 generic_selection:
595 	T_GENERIC T_LPAREN assignment_expression T_COMMA
596 	    generic_assoc_list T_RPAREN {
597 		/* generic selection requires C11 or later */
598 		c11ism(345);
599 		$$ = build_generic_selection($3, $5);
600 	}
601 ;
602 
603 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */
604 generic_assoc_list:
605 	generic_association
606 |	generic_assoc_list T_COMMA generic_association {
607 		$3->ga_prev = $1;
608 		$$ = $3;
609 	}
610 ;
611 
612 /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */
613 generic_association:
614 	type_name T_COLON assignment_expression {
615 		$$ = block_zero_alloc(sizeof(*$$), "generic");
616 		$$->ga_arg = $1;
617 		$$->ga_result = $3;
618 	}
619 |	T_DEFAULT T_COLON assignment_expression {
620 		$$ = block_zero_alloc(sizeof(*$$), "generic");
621 		$$->ga_arg = NULL;
622 		$$->ga_result = $3;
623 	}
624 ;
625 
626 /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2, C23 6.5.3.1 */
627 postfix_expression:
628 	primary_expression
629 |	postfix_expression T_LBRACK sys expression T_RBRACK {
630 		$$ = build_unary(INDIR, $3, build_binary($1, PLUS, $3, $4));
631 	}
632 |	postfix_expression T_LPAREN sys T_RPAREN {
633 		function_call *call =
634 		    expr_zero_alloc(sizeof(*call), "function_call");
635 		$$ = build_function_call($1, $3, call);
636 	}
637 |	postfix_expression T_LPAREN sys argument_expression_list T_RPAREN {
638 		$$ = build_function_call($1, $3, $4);
639 	}
640 |	postfix_expression point_or_arrow sys T_NAME {
641 		$$ = build_member_access($1, $2, $3, $4);
642 	}
643 |	postfix_expression T_INCDEC sys {
644 		$$ = build_unary($2 ? INCAFT : DECAFT, $3, $1);
645 	}
646 	/* Rule 'compound_literal' from C99 6.5.2.5. */
647 |	T_LPAREN type_name T_RPAREN {
648 		sym_t *tmp = mktempsym($2);
649 		begin_initialization(tmp);
650 		cgram_declare(tmp, true, NULL);
651 	} braced_initializer {
652 		if (!allow_c99)
653 			 /* compound literals are a C99/GCC extension */
654 			 gnuism(319);
655 		$$ = build_name(current_initsym(), false);
656 		end_initialization();
657 	}
658 	/* Rule 'compound_literal' with storage classes from C23 6.5.3.6. */
659 |	T_LPAREN storage_class_specifiers type_name T_RPAREN {
660 		sym_t *tmp = mktempsym($3);
661 		tmp->s_scl = $2;
662 		begin_initialization(tmp);
663 		cgram_declare(tmp, true, NULL);
664 	} braced_initializer {
665 		if (!allow_c99)
666 			 /* compound literals are a C99/GCC extension */
667 			 gnuism(319);
668 		$$ = build_name(current_initsym(), false);
669 		end_initialization();
670 	}
671 |	T_LPAREN compound_statement_lbrace {
672 		begin_statement_expr();
673 	} gcc_statement_expr_list {
674 		do_statement_expr($4);
675 	} compound_statement_rbrace T_RPAREN {
676 		$$ = end_statement_expr();
677 	}
678 ;
679 
680 /*
681  * The inner part of a GCC statement-expression of the form ({ ... }).
682  *
683  * https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html
684  */
685 gcc_statement_expr_list:
686 	gcc_statement_expr_item
687 |	gcc_statement_expr_list gcc_statement_expr_item {
688 		$$ = $2;
689 	}
690 ;
691 
692 gcc_statement_expr_item:
693 	declaration_or_error {
694 		clear_warning_flags();
695 		$$ = NULL;
696 	}
697 |	non_expr_statement {
698 		$$ = expr_alloc_tnode();
699 		$$->tn_type = gettyp(VOID);
700 	}
701 |	T_SEMI {
702 		$$ = expr_alloc_tnode();
703 		$$->tn_type = gettyp(VOID);
704 	}
705 |	expression T_SEMI {
706 		if ($1 == NULL) {	/* in case of syntax errors */
707 			$$ = expr_alloc_tnode();
708 			$$->tn_type = gettyp(VOID);
709 		} else {
710 			/* XXX: do that only on the last name */
711 			if ($1->tn_op == NAME)
712 				$1->u.sym->s_used = true;
713 			expr($1, false, false, false, false);
714 			suppress_fallthrough = false;
715 			$$ = $1;
716 		}
717 	}
718 ;
719 
720 point_or_arrow:			/* helper for 'postfix_expression' */
721 	T_POINT {
722 		set_sym_kind(SK_MEMBER);
723 		$$ = POINT;
724 	}
725 |	T_ARROW {
726 		set_sym_kind(SK_MEMBER);
727 		$$ = ARROW;
728 	}
729 ;
730 
731 /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2, C23 6.5.3.1 */
732 argument_expression_list:
733 	assignment_expression {
734 		$$ = expr_zero_alloc(sizeof(*$$), "function_call");
735 		add_function_argument($$, $1);
736 	}
737 |	argument_expression_list T_COMMA assignment_expression {
738 		$$ = $1;
739 		add_function_argument($1, $3);
740 	}
741 ;
742 
743 
744 /* C23 6.5.3.6 */
745 /* The rule 'compound_literal' is inlined into 'postfix_expression'. */
746 
747 /* C23 6.5.3.6 */
748 storage_class_specifiers:
749 	storage_class_specifier
750 |	storage_class_specifiers storage_class_specifier {
751 		// TODO C23: maybe merge multiple storage class specifiers
752 		$$ = $1;
753 	}
754 ;
755 
756 /* K&R 7.2, C90 ???, C99 6.5.3, C11 6.5.3, C23 6.5.4 */
757 unary_expression:
758 	postfix_expression
759 |	T_INCDEC sys unary_expression {
760 		$$ = build_unary($1 ? INCBEF : DECBEF, $2, $3);
761 	}
762 |	T_AMPER sys cast_expression {
763 		$$ = build_unary(ADDR, $2, $3);
764 	}
765 |	T_ASTERISK sys cast_expression {
766 		$$ = build_unary(INDIR, $2, $3);
767 	}
768 |	T_ADDITIVE sys cast_expression {
769 		if (!allow_c90 && $1 == PLUS)
770 			/* unary '+' is illegal in traditional C */
771 			warning(100);
772 		$$ = build_unary($1 == PLUS ? UPLUS : UMINUS, $2, $3);
773 	}
774 |	T_COMPLEMENT sys cast_expression {
775 		$$ = build_unary(COMPL, $2, $3);
776 	}
777 |	T_LOGNOT sys cast_expression {
778 		$$ = build_unary(NOT, $2, $3);
779 	}
780 |	T_REAL sys cast_expression {	/* GCC c_parser_unary_expression */
781 		$$ = build_unary(REAL, $2, $3);
782 	}
783 |	T_IMAG sys cast_expression {	/* GCC c_parser_unary_expression */
784 		$$ = build_unary(IMAG, $2, $3);
785 	}
786 |	T_EXTENSION cast_expression {	/* GCC c_parser_unary_expression */
787 		$$ = $2;
788 	}
789 |	T_SIZEOF unary_expression {
790 		$$ = $2 == NULL ? NULL : build_sizeof($2->tn_type);
791 		if ($$ != NULL)
792 			check_expr_misc($2,
793 			    false, false, false, false, false, true);
794 	}
795 |	T_SIZEOF T_LPAREN type_name T_RPAREN {
796 		$$ = build_sizeof($3);
797 	}
798 |	T_ALIGNOF unary_expression {
799 		/* non type argument to alignof is a GCC extension */
800 		gnuism(349);
801 		lint_assert($2 != NULL);
802 		$$ = build_alignof($2->tn_type);
803 	}
804 	/* K&R ---, C90 ---, C99 ---, C11 6.5.3, C23 6.5.4.4 */
805 |	T_ALIGNOF T_LPAREN type_name T_RPAREN {
806 		/* TODO: c11ism */
807 		$$ = build_alignof($3);
808 	}
809 ;
810 
811 /* C23 6.5.4 */
812 /* The rule 'unary_operator' is inlined into unary_expression. */
813 
814 /* K&R 7.2, C90 ???, C99 6.5.4, C11 6.5.4, C23 6.5.5 */
815 cast_expression:
816 	unary_expression
817 |	T_LPAREN type_name T_RPAREN sys cast_expression {
818 		$$ = cast($5, $4, $2);
819 	}
820 ;
821 
822 expression_opt:
823 	/* empty */ {
824 		$$ = NULL;
825 	}
826 |	expression
827 ;
828 
829 /* 'conditional_expression' also implements 'multiplicative_expression'. */
830 /* 'conditional_expression' also implements 'additive_expression'. */
831 /* 'conditional_expression' also implements 'shift_expression'. */
832 /* 'conditional_expression' also implements 'relational_expression'. */
833 /* 'conditional_expression' also implements 'equality_expression'. */
834 /* 'conditional_expression' also implements 'AND_expression'. */
835 /* 'conditional_expression' also implements 'exclusive_OR_expression'. */
836 /* 'conditional_expression' also implements 'inclusive_OR_expression'. */
837 /* 'conditional_expression' also implements 'logical_AND_expression'. */
838 /* 'conditional_expression' also implements 'logical_OR_expression'. */
839 /* K&R ???, C90 ???, C99 6.5.5 to 6.5.15, C11 6.5.5 to 6.5.15, C23 6.5.6 to 6.5.16 */
840 conditional_expression:
841 	cast_expression
842 |	conditional_expression T_ASTERISK sys conditional_expression {
843 		$$ = build_binary($1, MULT, $3, $4);
844 	}
845 |	conditional_expression T_MULTIPLICATIVE sys conditional_expression {
846 		$$ = build_binary($1, $2, $3, $4);
847 	}
848 |	conditional_expression T_ADDITIVE sys conditional_expression {
849 		$$ = build_binary($1, $2, $3, $4);
850 	}
851 |	conditional_expression T_SHIFT sys conditional_expression {
852 		$$ = build_binary($1, $2, $3, $4);
853 	}
854 |	conditional_expression T_RELATIONAL sys conditional_expression {
855 		$$ = build_binary($1, $2, $3, $4);
856 	}
857 |	conditional_expression T_EQUALITY sys conditional_expression {
858 		$$ = build_binary($1, $2, $3, $4);
859 	}
860 |	conditional_expression T_AMPER sys conditional_expression {
861 		$$ = build_binary($1, BITAND, $3, $4);
862 	}
863 |	conditional_expression T_BITXOR sys conditional_expression {
864 		$$ = build_binary($1, BITXOR, $3, $4);
865 	}
866 |	conditional_expression T_BITOR sys conditional_expression {
867 		$$ = build_binary($1, BITOR, $3, $4);
868 	}
869 |	conditional_expression T_LOGAND sys conditional_expression {
870 		$$ = build_binary($1, LOGAND, $3, $4);
871 	}
872 |	conditional_expression T_LOGOR sys conditional_expression {
873 		$$ = build_binary($1, LOGOR, $3, $4);
874 	}
875 |	conditional_expression T_QUEST sys
876 	    expression T_COLON sys conditional_expression {
877 		$$ = build_binary($1, QUEST, $3,
878 		    build_binary($4, COLON, $6, $7));
879 	}
880 ;
881 
882 /* K&R ???, C90 ???, C99 6.5.16, C11 6.5.16, C23 6.5.17.1 */
883 assignment_expression:
884 	conditional_expression
885 |	unary_expression T_ASSIGN sys assignment_expression {
886 		$$ = build_binary($1, ASSIGN, $3, $4);
887 	}
888 |	unary_expression T_OPASSIGN sys assignment_expression {
889 		$$ = build_binary($1, $2, $3, $4);
890 	}
891 ;
892 
893 /* C23 6.5.17.1 */
894 /* The rule 'assignment_operator' is inlined into 'assignment_expression'. */
895 
896 /* K&R ???, C90 ???, C99 6.5.17, C11 6.5.17, C23 6.5.18 */
897 expression:
898 	assignment_expression
899 |	expression T_COMMA sys assignment_expression {
900 		$$ = build_binary($1, COMMA, $3, $4);
901 	}
902 ;
903 
904 /* K&R ???, C90 ???, C99 6.6, C11 ???, C23 6.6 */
905 constant_expression:
906 	conditional_expression
907 ;
908 
909 declaration_or_error:
910 	declaration
911 |	error T_SEMI
912 ;
913 
914 /* K&R ???, C90 ???, C99 6.7, C11 ???, C23 6.7.1 */
915 declaration:
916 	begin_type_declmods end_type T_SEMI {
917 		if (dcs->d_scl == TYPEDEF)
918 			/* typedef declares no type name */
919 			warning(72);
920 		else
921 			/* empty declaration */
922 			warning(2);
923 	}
924 |	begin_type_declmods end_type notype_init_declarator_list T_SEMI {
925 		if (dcs->d_scl == TYPEDEF)
926 			/* syntax error '%s' */
927 			error(249, "missing base type for typedef");
928 		else
929 			/* old-style declaration; add 'int' */
930 			error(1);
931 	}
932 |	begin_type_declaration_specifiers end_type T_SEMI {
933 		if (dcs->d_scl == TYPEDEF)
934 			/* typedef declares no type name */
935 			warning(72);
936 		else if (!dcs->d_nonempty_decl)
937 			/* empty declaration */
938 			warning(2);
939 	}
940 |	begin_type_declaration_specifiers end_type
941 	    type_init_declarator_list T_SEMI
942 |	static_assert_declaration
943 ;
944 
945 /* TODO: Implement 'declaration_specifiers' from C23 6.7.1. */
946 
947 begin_type_declaration_specifiers:	/* see C99 6.7, C23 6.7.1 */
948 	begin_type_typespec {
949 		dcs_add_type($1);
950 	}
951 |	begin_type_declmods type_type_specifier {
952 		dcs_add_type($2);
953 	}
954 |	type_attribute begin_type_declaration_specifiers
955 |	begin_type_declaration_specifiers declmod
956 |	begin_type_declaration_specifiers notype_type_specifier {
957 		dcs_add_type($2);
958 	}
959 ;
960 
961 begin_type_declmods:		/* see C99 6.7 */
962 	begin_type type_qualifier {
963 		dcs_add_qualifiers($2);
964 	}
965 |	begin_type T_SCLASS {
966 		dcs_add_storage_class($2);
967 	}
968 |	begin_type T_FUNCTION_SPECIFIER {
969 		dcs_add_function_specifier($2);
970 	}
971 |	begin_type_declmods declmod
972 ;
973 
974 begin_type_specifier_qualifier_list:	/* see C11 6.7.2.1 */
975 	begin_type_specifier_qualifier_list_postfix
976 |	type_attribute_list begin_type_specifier_qualifier_list_postfix
977 ;
978 
979 begin_type_specifier_qualifier_list_postfix:
980 	begin_type_typespec {
981 		dcs_add_type($1);
982 	}
983 |	begin_type_qualifier_list type_type_specifier {
984 		dcs_add_type($2);
985 	}
986 |	begin_type_specifier_qualifier_list_postfix type_qualifier {
987 		dcs_add_qualifiers($2);
988 	}
989 |	begin_type_specifier_qualifier_list_postfix notype_type_specifier {
990 		dcs_add_type($2);
991 	}
992 |	begin_type_specifier_qualifier_list_postfix type_attribute
993 ;
994 
995 begin_type_typespec:
996 	begin_type notype_type_specifier {
997 		$$ = $2;
998 	}
999 |	begin_type T_TYPENAME {
1000 		$$ = getsym($2)->s_type;
1001 	}
1002 ;
1003 
1004 begin_type_qualifier_list:
1005 	begin_type type_qualifier {
1006 		dcs_add_qualifiers($2);
1007 	}
1008 |	begin_type_qualifier_list type_qualifier {
1009 		dcs_add_qualifiers($2);
1010 	}
1011 ;
1012 
1013 declmod:
1014 	type_qualifier {
1015 		dcs_add_qualifiers($1);
1016 	}
1017 |	T_SCLASS {
1018 		dcs_add_storage_class($1);
1019 	}
1020 |	T_FUNCTION_SPECIFIER {
1021 		dcs_add_function_specifier($1);
1022 	}
1023 |	type_attribute_list
1024 ;
1025 
1026 type_attribute_list_opt:
1027 	/* empty */
1028 |	type_attribute_list
1029 ;
1030 
1031 type_attribute_list:
1032 	type_attribute
1033 |	type_attribute_list type_attribute
1034 ;
1035 
1036 type_attribute_opt:
1037 	/* empty */
1038 |	type_attribute
1039 ;
1040 
1041 type_attribute:			/* See C11 6.7 declaration-specifiers */
1042 	gcc_attribute_specifier
1043 |	T_ALIGNAS T_LPAREN type_type_specifier T_RPAREN {		/* C11 6.7.5 */
1044 		dcs_add_alignas(build_sizeof($3));
1045 	}
1046 |	T_ALIGNAS T_LPAREN constant_expression T_RPAREN {	/* C11 6.7.5 */
1047 		dcs_add_alignas($3);
1048 	}
1049 |	T_PACKED {
1050 		dcs_add_packed();
1051 	}
1052 ;
1053 
1054 begin_type:
1055 	/* empty */ {
1056 		dcs_begin_type();
1057 	}
1058 |	attribute_specifier_sequence {
1059 		dcs_begin_type();
1060 		dcs->d_used = attributes_contain(&$1, "maybe_unused");
1061 	}
1062 ;
1063 
1064 end_type:
1065 	/* empty */ {
1066 		dcs_end_type();
1067 	}
1068 ;
1069 
1070 /* TODO: Implement 'declaration_specifier' from C23 6.7.1. */
1071 
1072 /*
1073  * For an explanation of 'type' and 'notype' prefixes in the following rules,
1074  * see https://www.gnu.org/software/bison/manual/bison.html#Semantic-Tokens.
1075  */
1076 
1077 /* C23 6.7.1 */
1078 /* The rule 'init_declarator_list' is split into the 'notype' and 'type' variants. */
1079 
1080 notype_init_declarator_list:
1081 	notype_init_declarator
1082 |	notype_init_declarator_list T_COMMA type_init_declarator
1083 ;
1084 
1085 type_init_declarator_list:
1086 	type_init_declarator
1087 |	type_init_declarator_list T_COMMA type_init_declarator
1088 ;
1089 
1090 /* C23 6.7.1 */
1091 /* The rule 'init_declarator' is split into the 'notype' and 'type' variants. */
1092 
1093 notype_init_declarator:
1094 	notype_declarator asm_or_symbolrename_opt {
1095 		cgram_declare($1, false, $2);
1096 		check_size($1);
1097 	}
1098 |	notype_declarator asm_or_symbolrename_opt {
1099 		begin_initialization($1);
1100 		cgram_declare($1, true, $2);
1101 	} T_ASSIGN initializer {
1102 		check_size($1);
1103 		end_initialization();
1104 	}
1105 ;
1106 
1107 type_init_declarator:
1108 	type_declarator asm_or_symbolrename_opt {
1109 		cgram_declare($1, false, $2);
1110 		check_size($1);
1111 	}
1112 |	type_declarator asm_or_symbolrename_opt {
1113 		begin_initialization($1);
1114 		cgram_declare($1, true, $2);
1115 	} T_ASSIGN initializer {
1116 		check_size($1);
1117 		end_initialization();
1118 	}
1119 ;
1120 
1121 
1122 /* TODO: Implement 'attribute_declaration' from C23 6.7.1. */
1123 
1124 /* K&R ???, C90 ???, C99 ???, C11 ???, C23 6.7.2 */
1125 storage_class_specifier:
1126 	T_SCLASS
1127 ;
1128 
1129 /* C99 6.7.2, C23 6.7.3.1 */
1130 /* The rule 'type_specifier' is split into the 'notype' and 'type' variants. */
1131 
1132 type_type_specifier:
1133 	notype_type_specifier
1134 |	T_TYPENAME {
1135 		$$ = getsym($1)->s_type;
1136 	}
1137 ;
1138 
1139 notype_type_specifier:		/* see C99 6.7.2 */
1140 	T_TYPE {
1141 		$$ = gettyp($1);
1142 	}
1143 |	T_TYPEOF T_LPAREN expression T_RPAREN {	/* GCC extension */
1144 		$$ = $3 != NULL ? block_dup_type($3->tn_type) : gettyp(INT);
1145 		$$->t_typeof = true;
1146 	}
1147 |	atomic_type_specifier
1148 |	struct_or_union_specifier {
1149 		end_declaration_level();
1150 		$$ = $1;
1151 	}
1152 |	enum_specifier {
1153 		end_declaration_level();
1154 		$$ = $1;
1155 	}
1156 ;
1157 
1158 /* K&R ---, C90 ---, C99 6.7.2.1, C11 ???, C23 6.7.3.2 */
1159 struct_or_union_specifier:
1160 	struct_or_union identifier_sym {
1161 		/*
1162 		 * STDC requires that "struct a;" always introduces
1163 		 * a new tag if "a" is not declared at current level
1164 		 *
1165 		 * yychar is valid because otherwise the parser would not
1166 		 * have been able to decide if it must shift or reduce
1167 		 */
1168 		$$ = make_tag_type($2, $1, false, yychar == T_SEMI);
1169 	}
1170 |	struct_or_union identifier_sym {
1171 		dcs->d_tag_type = make_tag_type($2, $1, true, false);
1172 	} braced_member_declaration_list {
1173 		$$ = complete_struct_or_union($4);
1174 	}
1175 |	struct_or_union {
1176 		dcs->d_tag_type = make_tag_type(NULL, $1, true, false);
1177 	} braced_member_declaration_list {
1178 		$$ = complete_struct_or_union($3);
1179 	}
1180 |	struct_or_union error {
1181 		set_sym_kind(SK_VCFT);
1182 		$$ = gettyp(INT);
1183 	}
1184 ;
1185 
1186 /* K&R ---, C90 ---, C99 6.7.2.1, C11 ???, C23 6.7.3.2 */
1187 struct_or_union:
1188 	T_STRUCT_OR_UNION {
1189 		set_sym_kind(SK_TAG);
1190 		begin_declaration_level($1 == STRUCT ? DLK_STRUCT : DLK_UNION);
1191 		dcs->d_sou_size_in_bits = 0;
1192 		dcs->d_sou_align = 1;
1193 		$$ = $1;
1194 	}
1195 |	struct_or_union type_attribute
1196 ;
1197 
1198 braced_member_declaration_list:	/* see C99 6.7.2.1 */
1199 	T_LBRACE {
1200 		set_sym_kind(SK_VCFT);
1201 	} member_declaration_list_with_rbrace {
1202 		$$ = $3;
1203 	}
1204 ;
1205 
1206 member_declaration_list_with_rbrace:	/* see C99 6.7.2.1 */
1207 	member_declaration_list T_RBRACE
1208 |	T_RBRACE {
1209 		/* XXX: Allowed since C23. */
1210 		$$ = NULL;
1211 	}
1212 ;
1213 
1214 /* K&R ???, C90 ???, C99 6.7.2.1, C11 6.7.2.1, C23 6.7.3.2 */
1215 /* Was named struct_declaration_list until C11. */
1216 member_declaration_list:
1217 	member_declaration
1218 |	member_declaration_list member_declaration {
1219 		$$ = concat_symbols($1, $2);
1220 	}
1221 ;
1222 
1223 /* K&R ???, C90 ???, C99 6.7.2.1, C11 6.7.2.1, C23 6.7.3.2 */
1224 /* Was named struct_declaration until C11. */
1225 member_declaration:
1226 	begin_type_qualifier_list end_type {
1227 		/* ^^ There is no check for the missing type-specifier. */
1228 		/* too late, i know, but getsym() compensates it */
1229 		set_sym_kind(SK_MEMBER);
1230 	} notype_member_declarator_list T_SEMI {
1231 		set_sym_kind(SK_VCFT);
1232 		$$ = $4;
1233 	}
1234 |	begin_type_specifier_qualifier_list end_type {
1235 		set_sym_kind(SK_MEMBER);
1236 	} type_member_declarator_list T_SEMI {
1237 		set_sym_kind(SK_VCFT);
1238 		$$ = $4;
1239 	}
1240 |	begin_type_qualifier_list end_type type_attribute_opt T_SEMI {
1241 		/* syntax error '%s' */
1242 		error(249, "member without type");
1243 		$$ = NULL;
1244 	}
1245 |	begin_type_specifier_qualifier_list end_type type_attribute_opt
1246 	    T_SEMI {
1247 		set_sym_kind(SK_VCFT);
1248 		if (!allow_c11 && !allow_gcc)
1249 			/* anonymous struct/union members is a C11 feature */
1250 			warning(49);
1251 		if (is_struct_or_union(dcs->d_type->t_tspec))
1252 			$$ = declare_unnamed_member();
1253 		else {
1254 			/* syntax error '%s' */
1255 			error(249, "unnamed member");
1256 			$$ = NULL;
1257 		}
1258 	}
1259 |	static_assert_declaration {
1260 		$$ = NULL;
1261 	}
1262 |	error T_SEMI {
1263 		set_sym_kind(SK_VCFT);
1264 		$$ = NULL;
1265 	}
1266 ;
1267 
1268 /* TODO: Implement 'specifier_qualifier_list' from C23 6.7.3.2. */
1269 
1270 /* TODO: Implement 'type_specifier_qualifier' from C23 6.7.3.2. */
1271 
1272 /* C23 6.7.3.2 */
1273 /* The rule 'member_declarator_list' is split into the 'type' and 'notype' variants. */
1274 /* Was named struct_declarator_list until C11. */
1275 
1276 notype_member_declarator_list:
1277 	notype_member_declarator {
1278 		$$ = declare_member($1);
1279 	}
1280 |	notype_member_declarator_list {
1281 		set_sym_kind(SK_MEMBER);
1282 	} T_COMMA type_member_declarator {
1283 		$$ = concat_symbols($1, declare_member($4));
1284 	}
1285 ;
1286 
1287 type_member_declarator_list:
1288 	type_member_declarator {
1289 		$$ = declare_member($1);
1290 	}
1291 |	type_member_declarator_list {
1292 		set_sym_kind(SK_MEMBER);
1293 	} T_COMMA type_member_declarator {
1294 		$$ = concat_symbols($1, declare_member($4));
1295 	}
1296 ;
1297 
1298 /* C23 6.7.3.2 */
1299 /* The rule 'member_declarator' is split into the 'type' and 'notype' variants. */
1300 /* Was named struct_declarator until C11. */
1301 
1302 notype_member_declarator:
1303 	notype_declarator
1304 	/* C99 6.7.2.1 */
1305 |	notype_declarator T_COLON constant_expression {
1306 		$$ = set_bit_field_width($1, to_int_constant($3, true));
1307 	}
1308 	/* C99 6.7.2.1 */
1309 |	{
1310 		set_sym_kind(SK_VCFT);
1311 	} T_COLON constant_expression {
1312 		$$ = set_bit_field_width(NULL, to_int_constant($3, true));
1313 	}
1314 ;
1315 
1316 type_member_declarator:
1317 	type_declarator
1318 |	type_declarator T_COLON constant_expression type_attribute_list_opt {
1319 		$$ = set_bit_field_width($1, to_int_constant($3, true));
1320 	}
1321 |	{
1322 		set_sym_kind(SK_VCFT);
1323 	} T_COLON constant_expression type_attribute_list_opt {
1324 		$$ = set_bit_field_width(NULL, to_int_constant($3, true));
1325 	}
1326 ;
1327 
1328 /* K&R ---, C90 6.5.2.2, C99 6.7.2.2, C11 6.7.2.2, C23 6.7.3.5 */
1329 enum_specifier:
1330 	enum gcc_attribute_specifier_list_opt identifier_sym {
1331 		$$ = make_tag_type($3, ENUM, false, false);
1332 	}
1333 |	enum gcc_attribute_specifier_list_opt identifier_sym {
1334 		dcs->d_tag_type = make_tag_type($3, ENUM, true, false);
1335 	} enum_declaration /*gcc_attribute_specifier_list_opt*/ {
1336 		$$ = complete_enum($5);
1337 	}
1338 |	enum gcc_attribute_specifier_list_opt {
1339 		dcs->d_tag_type = make_tag_type(NULL, ENUM, true, false);
1340 	} enum_declaration /*gcc_attribute_specifier_list_opt*/ {
1341 		$$ = complete_enum($4);
1342 	}
1343 |	enum error {
1344 		set_sym_kind(SK_VCFT);
1345 		$$ = gettyp(INT);
1346 	}
1347 ;
1348 
1349 enum:				/* helper for C99 6.7.2.2 */
1350 	T_ENUM {
1351 		set_sym_kind(SK_TAG);
1352 		begin_declaration_level(DLK_ENUM);
1353 	}
1354 ;
1355 
1356 enum_declaration:		/* helper for C99 6.7.2.2 */
1357 	T_LBRACE {
1358 		set_sym_kind(SK_VCFT);
1359 		enumval = 0;
1360 	} enums_with_opt_comma T_RBRACE {
1361 		$$ = $3;
1362 	}
1363 ;
1364 
1365 enums_with_opt_comma:		/* helper for C99 6.7.2.2 */
1366 	enumerator_list
1367 |	enumerator_list T_COMMA {
1368 		if (!allow_c99 && !allow_trad)
1369 			/* trailing ',' in enum declaration requires C99 ... */
1370 			error(54);
1371 		else
1372 			/* trailing ',' in enum declaration requires C99 ... */
1373 			c99ism(54);
1374 		$$ = $1;
1375 	}
1376 ;
1377 
1378 /* C99 6.7.2.2, C23 6.7.3.3 */
1379 enumerator_list:
1380 	enumerator
1381 |	enumerator_list T_COMMA enumerator {
1382 		$$ = concat_symbols($1, $3);
1383 	}
1384 |	error {
1385 		$$ = NULL;
1386 	}
1387 ;
1388 
1389 /* C99 6.7.2.2, C23 6.7.3.3 */
1390 enumerator:
1391 	identifier_sym gcc_attribute_specifier_list_opt {
1392 		$$ = enumeration_constant($1, enumval, true);
1393 	}
1394 |	identifier_sym gcc_attribute_specifier_list_opt
1395 	    T_ASSIGN constant_expression {
1396 		$$ = enumeration_constant($1, to_int_constant($4, true),
1397 		    false);
1398 	}
1399 ;
1400 
1401 /* TODO: Implement 'enum_type_specifier' from C23 6.7.3.3. */
1402 
1403 /* K&R ---, C90 ---, C99 ---, C11 6.7.2.4, C23 6.7.3.5 */
1404 atomic_type_specifier:
1405 	atomic T_LPAREN type_name T_RPAREN {
1406 		$$ = $3;
1407 	}
1408 ;
1409 
1410 atomic:				/* helper */
1411 	T_ATOMIC {
1412 		/* TODO: First fix c11ism, then use it here. */
1413 		if (!allow_c11)
1414 			/* '_Atomic' requires C11 or later */
1415 			error(350);
1416 	}
1417 ;
1418 
1419 /* TODO: Implement 'typeof_specifier' from C23 6.7.3.6. */
1420 
1421 /* TODO: Implement 'typeof_specifier_argument' from C23 6.7.3.6. */
1422 
1423 /* C99 6.7.3, C23 6.7.4.1 */
1424 type_qualifier:
1425 	T_QUAL
1426 |	atomic {
1427 		$$ = (type_qualifiers){ .tq_atomic = true };
1428 	}
1429 ;
1430 
1431 /* TODO: Implement 'function_specifier' from C23 6.7.5. */
1432 
1433 /* TODO: Implement 'alignment_specifier' from C23 6.7.6. */
1434 
1435 /* C23 6.7.7.1 */
1436 /* The rule 'declarator' is split into the 'notype' and 'type' variants. */
1437 
1438 notype_declarator:
1439 	notype_direct_declarator
1440 |	pointer notype_direct_declarator {
1441 		$$ = add_pointer($2, $1);
1442 	}
1443 ;
1444 
1445 type_declarator:
1446 	type_direct_declarator
1447 |	pointer type_direct_declarator {
1448 		$$ = add_pointer($2, $1);
1449 	}
1450 ;
1451 
1452 /* C23 6.7.7.1 */
1453 /* The rule 'direct_declarator' is split into the 'notype' and 'type' variants. */
1454 
1455 notype_direct_declarator:
1456 	type_attribute_list_opt T_NAME {
1457 		$$ = declarator_name(getsym($2));
1458 	}
1459 |	type_attribute_list_opt T_LPAREN type_declarator T_RPAREN {
1460 		$$ = $3;
1461 	}
1462 |	notype_direct_declarator T_LBRACK array_size_opt T_RBRACK {
1463 		$$ = add_array($1, $3.has_dim, $3.dim);
1464 	}
1465 |	notype_direct_declarator param_list asm_or_symbolrename_opt {
1466 		$$ = add_function(symbolrename($1, $3), $2);
1467 		end_declaration_level();
1468 		block_level--;
1469 	}
1470 |	notype_direct_declarator type_attribute
1471 ;
1472 
1473 type_direct_declarator:
1474 	type_attribute_list_opt identifier {
1475 		$$ = declarator_name(getsym($2));
1476 	}
1477 |	type_attribute_list_opt T_LPAREN type_declarator T_RPAREN {
1478 		$$ = $3;
1479 	}
1480 |	type_direct_declarator T_LBRACK array_size_opt T_RBRACK {
1481 		$$ = add_array($1, $3.has_dim, $3.dim);
1482 	}
1483 |	type_direct_declarator param_list asm_or_symbolrename_opt {
1484 		$$ = add_function(symbolrename($1, $3), $2);
1485 		end_declaration_level();
1486 		block_level--;
1487 	}
1488 |	type_direct_declarator type_attribute
1489 ;
1490 
1491 
1492 /* TODO: Implement 'array_declarator' from C23 6.7.7.1. */
1493 
1494 /* TODO: Implement 'function_declarator' from C23 6.7.7.1. */
1495 
1496 /* C99 6.7.5, C23 6.7.7.1 */
1497 pointer:
1498 	T_ASTERISK type_qualifier_list_opt {
1499 		$$ = xcalloc(1, sizeof(*$$));
1500 		add_type_qualifiers(&$$->qualifiers, $2);
1501 	}
1502 |	T_ASTERISK type_qualifier_list_opt pointer {
1503 		$$ = xcalloc(1, sizeof(*$$));
1504 		add_type_qualifiers(&$$->qualifiers, $2);
1505 		$$ = append_qualified_pointer($$, $3);
1506 	}
1507 ;
1508 
1509 /* see C99 6.7.5, C23 6.7.7.1 */
1510 type_qualifier_list_opt:
1511 	/* empty */ {
1512 		$$ = (type_qualifiers){ .tq_const = false };
1513 	}
1514 |	type_qualifier_list
1515 ;
1516 
1517 /* C99 6.7.5 */
1518 type_qualifier_list:
1519 	type_qualifier
1520 |	type_qualifier_list type_qualifier {
1521 		$$ = $1;
1522 		add_type_qualifiers(&$$, $2);
1523 	}
1524 ;
1525 
1526 /* TODO: Implement 'parameter_type_list' from C23 6.7.7.1. */
1527 
1528 /* TODO: Implement 'parameter_list' from C23 6.7.7.1. */
1529 
1530 /* C23 6.7.7.1 */
1531 /* XXX: C99 6.7.5 defines the same name, but it looks completely different. */
1532 parameter_declaration:
1533 	begin_type_declmods end_type {
1534 		/* ^^ There is no check for the missing type-specifier. */
1535 		$$ = declare_parameter(abstract_name(), false);
1536 	}
1537 |	begin_type_declaration_specifiers end_type {
1538 		$$ = declare_parameter(abstract_name(), false);
1539 	}
1540 |	begin_type_declmods end_type notype_param_declarator {
1541 		/* ^^ There is no check for the missing type-specifier. */
1542 		$$ = declare_parameter($3, false);
1543 	}
1544 	/*
1545 	 * type_param_declarator is needed because of following conflict:
1546 	 * "typedef int a; f(int (a));" could be parsed as
1547 	 * "function with argument a of type int", or
1548 	 * "function with an unnamed (abstract) argument of type function".
1549 	 * This grammar realizes the second case.
1550 	 */
1551 |	begin_type_declaration_specifiers end_type type_param_declarator {
1552 		$$ = declare_parameter($3, false);
1553 	}
1554 |	begin_type_declmods end_type abstract_declarator {
1555 		/* ^^ There is no check for the missing type-specifier. */
1556 		$$ = declare_parameter($3, false);
1557 	}
1558 |	begin_type_declaration_specifiers end_type abstract_declarator {
1559 		$$ = declare_parameter($3, false);
1560 	}
1561 ;
1562 
1563 /*
1564  * The two distinct rules type_param_declarator and notype_param_declarator
1565  * avoid a conflict in parameter lists. A typename enclosed in parentheses is
1566  * always treated as a typename, not an argument name. For example, after
1567  * "typedef double a;", the declaration "f(int (a));" is interpreted as
1568  * "f(int (double));", not "f(int a);".
1569  */
1570 type_param_declarator:
1571 	direct_param_declarator
1572 |	pointer direct_param_declarator {
1573 		$$ = add_pointer($2, $1);
1574 	}
1575 ;
1576 
1577 notype_param_declarator:
1578 	direct_notype_param_declarator
1579 |	pointer direct_notype_param_declarator {
1580 		$$ = add_pointer($2, $1);
1581 	}
1582 ;
1583 
1584 direct_param_declarator:
1585 	identifier type_attribute_list {
1586 		$$ = declarator_name(getsym($1));
1587 	}
1588 |	identifier {
1589 		$$ = declarator_name(getsym($1));
1590 	}
1591 |	T_LPAREN notype_param_declarator T_RPAREN {
1592 		$$ = $2;
1593 	}
1594 |	direct_param_declarator T_LBRACK array_size_opt T_RBRACK
1595 	    gcc_attribute_specifier_list_opt {
1596 		$$ = add_array($1, $3.has_dim, $3.dim);
1597 	}
1598 |	direct_param_declarator param_list asm_or_symbolrename_opt {
1599 		$$ = add_function(symbolrename($1, $3), $2);
1600 		end_declaration_level();
1601 		block_level--;
1602 	}
1603 ;
1604 
1605 direct_notype_param_declarator:
1606 	identifier {
1607 		$$ = declarator_name(getsym($1));
1608 	}
1609 |	T_LPAREN notype_param_declarator T_RPAREN {
1610 		$$ = $2;
1611 	}
1612 |	direct_notype_param_declarator T_LBRACK array_size_opt T_RBRACK {
1613 		$$ = add_array($1, $3.has_dim, $3.dim);
1614 	}
1615 |	direct_notype_param_declarator param_list asm_or_symbolrename_opt {
1616 		$$ = add_function(symbolrename($1, $3), $2);
1617 		end_declaration_level();
1618 		block_level--;
1619 	}
1620 ;
1621 
1622 param_list:
1623 	T_LPAREN {
1624 		block_level++;
1625 		begin_declaration_level(DLK_PROTO_PARAMS);
1626 	} identifier_list T_RPAREN {
1627 		$$ = (parameter_list){ .first = $3 };
1628 	}
1629 |	abstract_decl_param_list
1630 ;
1631 
1632 array_size_opt:
1633 	/* empty */ {
1634 		$$.has_dim = false;
1635 		$$.dim = 0;
1636 	}
1637 |	T_ASTERISK {
1638 		/* since C99; variable length array of unspecified size */
1639 		$$.has_dim = false; /* TODO: maybe change to true */
1640 		$$.dim = 0;	/* just as a placeholder */
1641 	}
1642 |	type_qualifier_list_opt T_SCLASS constant_expression {
1643 		/* C11 6.7.6.3p7 */
1644 		if ($2 != STATIC)
1645 			yyerror("Bad attribute");
1646 		/* static array size requires C11 or later */
1647 		c11ism(343);
1648 		$$.has_dim = true;
1649 		$$.dim = $3 == NULL ? 0 : to_int_constant($3, false);
1650 	}
1651 |	type_qualifier {
1652 		/* C11 6.7.6.2 */
1653 		if (!$1.tq_restrict)
1654 			yyerror("Bad attribute");
1655 		$$.has_dim = true;
1656 		$$.dim = 0;
1657 	}
1658 |	constant_expression {
1659 		$$.has_dim = true;
1660 		$$.dim = $1 == NULL ? 0 : to_int_constant($1, false);
1661 	}
1662 ;
1663 
1664 identifier_list:		/* C99 6.7.5 */
1665 	T_NAME {
1666 		$$ = old_style_function_parameter_name(getsym($1));
1667 	}
1668 |	identifier_list T_COMMA T_NAME {
1669 		$$ = concat_symbols($1,
1670 		    old_style_function_parameter_name(getsym($3)));
1671 	}
1672 |	identifier_list error
1673 ;
1674 
1675 /* C99 6.7.6, C23 6.7.8 */
1676 /* XXX: C99 requires an additional specifier-qualifier-list. */
1677 type_name:
1678 	{
1679 		begin_declaration_level(DLK_ABSTRACT);
1680 	} abstract_declaration {
1681 		end_declaration_level();
1682 		$$ = $2->s_type;
1683 	}
1684 ;
1685 
1686 abstract_declaration:		/* specific to lint */
1687 	begin_type_qualifier_list end_type {
1688 		$$ = declare_abstract_type(abstract_name());
1689 	}
1690 |	begin_type_specifier_qualifier_list end_type {
1691 		$$ = declare_abstract_type(abstract_name());
1692 	}
1693 |	begin_type_qualifier_list end_type abstract_declarator {
1694 		$$ = declare_abstract_type($3);
1695 	}
1696 |	begin_type_specifier_qualifier_list end_type abstract_declarator {
1697 		$$ = declare_abstract_type($3);
1698 	}
1699 ;
1700 
1701 abstract_decl_param_list:	/* specific to lint */
1702 	abstract_decl_lparen T_RPAREN type_attribute_opt {
1703 		$$ = (parameter_list){ .first = NULL };
1704 	}
1705 |	abstract_decl_lparen vararg_parameter_type_list T_RPAREN
1706 	    type_attribute_opt {
1707 		$$ = $2;
1708 		$$.prototype = true;
1709 	}
1710 |	abstract_decl_lparen error T_RPAREN type_attribute_opt {
1711 		$$ = (parameter_list){ .first = NULL };
1712 	}
1713 ;
1714 
1715 abstract_decl_lparen:		/* specific to lint */
1716 	T_LPAREN {
1717 		block_level++;
1718 		begin_declaration_level(DLK_PROTO_PARAMS);
1719 	}
1720 ;
1721 
1722 vararg_parameter_type_list:	/* specific to lint */
1723 	parameter_type_list
1724 |	parameter_type_list T_COMMA T_ELLIPSIS {
1725 		$$ = $1;
1726 		$$.vararg = true;
1727 	}
1728 |	T_ELLIPSIS {
1729 		/* TODO: C99 6.7.5 makes this an error as well. */
1730 		if (!allow_trad && !allow_c99)
1731 			/* C90 to C17 require formal parameter before '...' */
1732 			error(84);
1733 		else if (allow_c90)
1734 			/* C90 to C17 require formal parameter before '...' */
1735 			warning(84);
1736 		$$ = (parameter_list){ .vararg = true };
1737 	}
1738 ;
1739 
1740 /* XXX: C99 6.7.5 defines the same name, but it looks different. */
1741 parameter_type_list:
1742 	parameter_declaration {
1743 		$$ = (parameter_list){ .first = $1 };
1744 	}
1745 |	parameter_type_list T_COMMA parameter_declaration {
1746 		$$ = $1;
1747 		$$.first = concat_symbols($1.first, $3);
1748 	}
1749 ;
1750 
1751 /* K&R 8.7, C90 ???, C99 6.7.6, C11 6.7.7, C23 6.7.8 */
1752 /* In K&R, abstract-declarator could be empty and was still simpler. */
1753 abstract_declarator:
1754 	pointer {
1755 		$$ = add_pointer(abstract_name(), $1);
1756 	}
1757 |	direct_abstract_declarator
1758 |	pointer direct_abstract_declarator {
1759 		$$ = add_pointer($2, $1);
1760 	}
1761 |	type_attribute_list direct_abstract_declarator {
1762 		$$ = $2;
1763 	}
1764 |	pointer type_attribute_list direct_abstract_declarator {
1765 		$$ = add_pointer($3, $1);
1766 	}
1767 ;
1768 
1769 /* K&R ---, C90 ???, C99 6.7.6, C11 6.7.7, C23 6.7.8 */
1770 direct_abstract_declarator:
1771 	/* TODO: sort rules according to C99 */
1772 	T_LPAREN abstract_declarator T_RPAREN {
1773 		$$ = $2;
1774 	}
1775 |	T_LBRACK array_size_opt T_RBRACK {
1776 		$$ = add_array(abstract_name(), $2.has_dim, $2.dim);
1777 	}
1778 |	direct_abstract_declarator T_LBRACK array_size_opt T_RBRACK {
1779 		$$ = add_array($1, $3.has_dim, $3.dim);
1780 	}
1781 |	abstract_decl_param_list asm_or_symbolrename_opt {
1782 		sym_t *name = abstract_enclosing_name();
1783 		$$ = add_function(symbolrename(name, $2), $1);
1784 		end_declaration_level();
1785 		block_level--;
1786 	}
1787 |	direct_abstract_declarator abstract_decl_param_list
1788 	    asm_or_symbolrename_opt {
1789 		$$ = add_function(symbolrename($1, $3), $2);
1790 		end_declaration_level();
1791 		block_level--;
1792 	}
1793 |	direct_abstract_declarator type_attribute_list
1794 ;
1795 
1796 /* TODO: Implement 'array_abstract_declarator' from C23 6.7.8. */
1797 
1798 /* TODO: Implement 'function_abstract_declarator' from C23 6.7.8. */
1799 
1800 /* TODO: Implement 'typedef_name' from C23 6.7.9. */
1801 
1802 /* C23 6.7.11 */
1803 /* K&R ---, C90 ---, C99 6.7.8, C11 6.7.9, C23 6.7.10 */
1804 braced_initializer:
1805 	init_lbrace init_rbrace {
1806 		/* empty initializer braces require C23 or later */
1807 		c23ism(353);
1808 	}
1809 |	init_lbrace initializer_list init_rbrace
1810 |	init_lbrace initializer_list T_COMMA init_rbrace
1811 ;
1812 
1813 /* C99 6.7.8, C23 6.7.11 */
1814 initializer:
1815 	assignment_expression {
1816 		init_expr($1);
1817 	}
1818 |	init_lbrace init_rbrace {
1819 		/* XXX: Empty braces are not covered by C99 6.7.8. */
1820 	}
1821 |	init_lbrace initializer_list init_rbrace
1822 |	init_lbrace initializer_list T_COMMA init_rbrace
1823 	/* XXX: What is this error handling for? */
1824 |	error
1825 ;
1826 
1827 /* C99 6.7.8, C23 6.7.11 */
1828 initializer_list:
1829 	initializer
1830 |	designation initializer
1831 |	initializer_list T_COMMA initializer
1832 |	initializer_list T_COMMA designation initializer
1833 ;
1834 
1835 /* C99 6.7.8, C23 6.7.11 */
1836 designation:
1837 	{
1838 		begin_designation();
1839 	} designator_list T_ASSIGN
1840 |	identifier T_COLON {
1841 		/* GCC style struct or union member name in initializer */
1842 		gnuism(315);
1843 		begin_designation();
1844 		add_designator_member($1);
1845 	}
1846 ;
1847 
1848 /* C99 6.7.8, C23 6.7.11 */
1849 designator_list:
1850 	designator
1851 |	designator_list designator
1852 ;
1853 
1854 /* C99 6.7.8, C23 6.7.11 */
1855 designator:
1856 	T_LBRACK range T_RBRACK {
1857 		if (!allow_c99)
1858 			/* array initializer with designators is a C99 ... */
1859 			warning(321);
1860 		add_designator_subscript($2);
1861 	}
1862 |	T_POINT identifier {
1863 		if (!allow_c99)
1864 			/* struct or union member name in initializer is ... */
1865 			warning(313);
1866 		add_designator_member($2);
1867 	}
1868 ;
1869 
1870 /* C23 6.7.12 */
1871 static_assert_declaration:
1872 	T_STATIC_ASSERT T_LPAREN constant_expression T_COMMA T_STRING
1873 	    T_RPAREN T_SEMI {
1874 		/* '_Static_assert' requires C11 or later */
1875 		c11ism(354);
1876 	}
1877 |	T_STATIC_ASSERT T_LPAREN constant_expression T_RPAREN T_SEMI {
1878 		/* '_Static_assert' without message requires C23 or later */
1879 		c23ism(355);
1880 	}
1881 ;
1882 
1883 range:
1884 	constant_expression {
1885 		$$.lo = to_int_constant($1, true);
1886 		$$.hi = $$.lo;
1887 	}
1888 |	constant_expression T_ELLIPSIS constant_expression {
1889 		$$.lo = to_int_constant($1, true);
1890 		$$.hi = to_int_constant($3, true);
1891 		/* initialization with '[a...b]' is a GCC extension */
1892 		gnuism(340);
1893 	}
1894 ;
1895 
1896 init_lbrace:			/* helper */
1897 	T_LBRACE {
1898 		init_lbrace();
1899 	}
1900 ;
1901 
1902 init_rbrace:			/* helper */
1903 	T_RBRACE {
1904 		init_rbrace();
1905 	}
1906 ;
1907 
1908 /* C23 6.7.13.2 */
1909 attribute_specifier_sequence:
1910 	attribute_specifier {
1911 		$$ = (attribute_list) { NULL, 0, 0 };
1912 		attribute_list_add_all(&$$, $1);
1913 	}
1914 |	attribute_specifier_sequence attribute_specifier {
1915 		$$ = $1;
1916 		attribute_list_add_all(&$$, $2);
1917 	}
1918 ;
1919 
1920 /* C23 6.7.13.2 */
1921 attribute_specifier:
1922 	T_LBRACK T_LBRACK attribute_list T_RBRACK T_RBRACK {
1923 		$$ = $3;
1924 	}
1925 ;
1926 
1927 /* C23 6.7.13.2 */
1928 attribute_list:
1929 	/* empty */ {
1930 		$$ = (attribute_list) { NULL, 0, 0 };
1931 	}
1932 |	attribute {
1933 		$$ = (attribute_list) { NULL, 0, 0 };
1934 		attribute_list_add(&$$, $1);
1935 	}
1936 |	attribute_list T_COMMA
1937 |	attribute_list T_COMMA attribute {
1938 		$$ = $1;
1939 		attribute_list_add(&$$, $3);
1940 	}
1941 ;
1942 
1943 /* C23 6.7.13.2 */
1944 attribute:
1945 	identifier {
1946 		$$ = new_attribute(NULL, $1, NULL);
1947 	}
1948 |	identifier T_DCOLON identifier {
1949 		$$ = new_attribute($1, $3, NULL);
1950 	}
1951 |	identifier attribute_argument_clause {
1952 		$$ = new_attribute(NULL, $1, &$2);
1953 	}
1954 |	identifier T_DCOLON identifier attribute_argument_clause {
1955 		$$ = new_attribute($1, $3, &$4);
1956 	}
1957 ;
1958 
1959 /* The rule 'attribute_token' is inlined into 'attribute'. */
1960 /* The rule 'standard_attribute' is inlined into 'attribute_token'. */
1961 /* The rule 'attribute_prefixed_token' is inlined into 'attribute_token'. */
1962 /* The rule 'attribute_prefix' is inlined into 'attribute_token'. */
1963 
1964 /* C23 6.7.13.2 */
1965 attribute_argument_clause:
1966 	T_LPAREN {
1967 		$$ = read_balanced_token_sequence();
1968 	}
1969 ;
1970 
1971 /* The rule 'balanced_token_sequence' is inlined into 'attribute_argument_clause'. */
1972 /* The rule 'balanced_token' is inlined into 'balanced_token_sequence'. */
1973 
1974 asm_or_symbolrename_opt:	/* GCC extensions */
1975 	/* empty */ {
1976 		$$ = NULL;
1977 	}
1978 |	T_ASM T_LPAREN T_STRING T_RPAREN gcc_attribute_specifier_list_opt {
1979 		freeyyv(&$3, T_STRING);
1980 		$$ = NULL;
1981 	}
1982 |	T_SYMBOLRENAME T_LPAREN T_NAME T_RPAREN
1983 	    gcc_attribute_specifier_list_opt {
1984 		$$ = $3;
1985 	}
1986 ;
1987 
1988 /* K&R ???, C90 ???, C99 6.8, C11 ???, C23 6.8.1 */
1989 statement:
1990 	expression_statement
1991 |	non_expr_statement
1992 ;
1993 
1994 /* Helper to avoid shift/reduce conflict in 'label: __attribute__ ;'. */
1995 no_attr_statement:
1996 	expression_statement
1997 |	no_attr_non_expr_statement
1998 ;
1999 
2000 non_expr_statement:		/* helper for C99 6.8 */
2001 	gcc_attribute_specifier /* ((__fallthrough__)) */ T_SEMI
2002 |	no_attr_non_expr_statement
2003 ;
2004 
2005 /* Helper to avoid shift/reduce conflict in 'label: __attribute__ ;'. */
2006 no_attr_non_expr_statement:
2007 	labeled_statement
2008 |	compound_statement
2009 |	selection_statement
2010 |	iteration_statement
2011 |	jump_statement {
2012 		suppress_fallthrough = false;
2013 	}
2014 |	asm_statement
2015 ;
2016 
2017 /* TODO: Implement 'unlabeled_statement' from C23 6.8.1. */
2018 
2019 /* TODO: Implement 'primary_block' from C23 6.8.1. */
2020 
2021 /* TODO: Implement 'secondary_block' from C23 6.8.1. */
2022 
2023 /* C23 6.8.2 */
2024 label:
2025 	T_NAME T_COLON {
2026 		set_sym_kind(SK_LABEL);
2027 		named_label(getsym($1));
2028 	}
2029 |	T_CASE constant_expression T_COLON {
2030 		case_label($2);
2031 		suppress_fallthrough = true;
2032 	}
2033 |	T_CASE constant_expression T_ELLIPSIS constant_expression T_COLON {
2034 		/* XXX: We don't fill all cases */
2035 		case_label($2);
2036 		suppress_fallthrough = true;
2037 	}
2038 |	T_DEFAULT T_COLON {
2039 		default_label();
2040 		suppress_fallthrough = true;
2041 	}
2042 ;
2043 
2044 /* C99 6.8.1, C23 6.8.2 */
2045 labeled_statement:
2046 	label gcc_attribute_specifier_list_opt no_attr_statement
2047 ;
2048 
2049 /* C99 6.8.2, C23 6.8.3 */
2050 compound_statement:
2051 	compound_statement_lbrace compound_statement_rbrace
2052 |	compound_statement_lbrace block_item_list compound_statement_rbrace
2053 ;
2054 
2055 compound_statement_lbrace:
2056 	T_LBRACE {
2057 		block_level++;
2058 		mem_block_level++;
2059 		debug_step("%s: mem_block_level = %zu",
2060 		    "compound_statement_lbrace", mem_block_level);
2061 		begin_declaration_level(DLK_AUTO);
2062 	}
2063 ;
2064 
2065 compound_statement_rbrace:
2066 	T_RBRACE {
2067 		end_declaration_level();
2068 		if (!in_statement_expr())
2069 			level_free_all(mem_block_level);	/* leak */
2070 		mem_block_level--;
2071 		debug_step("%s: mem_block_level = %zu",
2072 		    "compound_statement_rbrace", mem_block_level);
2073 		block_level--;
2074 		suppress_fallthrough = false;
2075 	}
2076 ;
2077 
2078 /* C99 6.8.2, C23 6.8.3 */
2079 block_item_list:
2080 	block_item
2081 |	block_item_list block_item {
2082 		if ($1 && !$2)
2083 			/* declarations after statements is a C99 feature */
2084 			c99ism(327);
2085 		$$ = $1 || $2;
2086 	}
2087 ;
2088 
2089 /* C99 6.8.2, C23 6.8.3 */
2090 block_item:
2091 	declaration_or_error {
2092 		$$ = false;
2093 		restore_warning_flags();
2094 	}
2095 |	statement {
2096 		$$ = true;
2097 		restore_warning_flags();
2098 	}
2099 ;
2100 
2101 /* C99 6.8.3, C23 6.8.4 */
2102 expression_statement:
2103 	expression T_SEMI {
2104 		expr($1, false, false, false, false);
2105 		suppress_fallthrough = false;
2106 	}
2107 |	T_SEMI {
2108 		check_statement_reachable();
2109 		suppress_fallthrough = false;
2110 	}
2111 |	attribute_specifier_sequence expression T_SEMI {
2112 		debug_attribute_list(&$1);
2113 		expr($2, false, false, false, false);
2114 		suppress_fallthrough = false;
2115 	}
2116 |	attribute_specifier_sequence T_SEMI {
2117 		debug_attribute_list(&$1);
2118 		check_statement_reachable();
2119 		suppress_fallthrough = attributes_contain(&$1, "fallthrough");
2120 	}
2121 ;
2122 
2123 /* C99 6.8.4, C23 6.8.5.1 */
2124 selection_statement:
2125 	if_without_else %prec T_THEN {
2126 		save_warning_flags();
2127 		stmt_if_then_stmt();
2128 		stmt_if_else_stmt(false);
2129 	}
2130 |	if_without_else T_ELSE {
2131 		save_warning_flags();
2132 		stmt_if_then_stmt();
2133 	} statement {
2134 		clear_warning_flags();
2135 		stmt_if_else_stmt(true);
2136 	}
2137 |	if_without_else T_ELSE error {
2138 		clear_warning_flags();
2139 		stmt_if_else_stmt(false);
2140 	}
2141 |	switch_expr statement {
2142 		clear_warning_flags();
2143 		stmt_switch_expr_stmt();
2144 	}
2145 |	switch_expr error {
2146 		clear_warning_flags();
2147 		stmt_switch_expr_stmt();
2148 	}
2149 ;
2150 
2151 if_without_else:		/* see C99 6.8.4 */
2152 	if_expr statement
2153 |	if_expr error
2154 ;
2155 
2156 if_expr:			/* see C99 6.8.4 */
2157 	T_IF T_LPAREN expression T_RPAREN {
2158 		stmt_if_expr($3);
2159 		clear_warning_flags();
2160 	}
2161 ;
2162 
2163 switch_expr:			/* see C99 6.8.4 */
2164 	T_SWITCH T_LPAREN expression T_RPAREN {
2165 		stmt_switch_expr($3);
2166 		clear_warning_flags();
2167 	}
2168 ;
2169 
2170 /* C99 6.8.5, C23 6.8.6.1 */
2171 iteration_statement:
2172 	while_expr statement {
2173 		clear_warning_flags();
2174 		stmt_while_expr_stmt();
2175 	}
2176 |	while_expr error {
2177 		clear_warning_flags();
2178 		stmt_while_expr_stmt();
2179 	}
2180 |	do_statement T_WHILE T_LPAREN expression T_RPAREN T_SEMI {
2181 		stmt_do_while_expr($4);
2182 		suppress_fallthrough = false;
2183 	}
2184 |	do error {
2185 		clear_warning_flags();
2186 		stmt_do_while_expr(NULL);
2187 	}
2188 |	for_exprs statement {
2189 		clear_warning_flags();
2190 		stmt_for_exprs_stmt();
2191 		end_declaration_level();
2192 		block_level--;
2193 	}
2194 |	for_exprs error {
2195 		clear_warning_flags();
2196 		stmt_for_exprs_stmt();
2197 		end_declaration_level();
2198 		block_level--;
2199 	}
2200 ;
2201 
2202 while_expr:			/* see C99 6.8.5 */
2203 	T_WHILE T_LPAREN expression T_RPAREN {
2204 		stmt_while_expr($3);
2205 		clear_warning_flags();
2206 	}
2207 ;
2208 
2209 do_statement:			/* see C99 6.8.5 */
2210 	do statement {
2211 		clear_warning_flags();
2212 	}
2213 ;
2214 
2215 do:				/* see C99 6.8.5 */
2216 	T_DO {
2217 		stmt_do();
2218 	}
2219 ;
2220 
2221 for_start:			/* see C99 6.8.5 */
2222 	T_FOR T_LPAREN {
2223 		begin_declaration_level(DLK_AUTO);
2224 		block_level++;
2225 	}
2226 ;
2227 
2228 for_exprs:			/* see C99 6.8.5 */
2229 	for_start
2230 	    begin_type_declaration_specifiers end_type
2231 	    notype_init_declarator_list T_SEMI
2232 	    expression_opt T_SEMI
2233 	    expression_opt T_RPAREN {
2234 		/* variable declaration in for loop */
2235 		c99ism(325);
2236 		stmt_for_exprs(NULL, $6, $8);
2237 		clear_warning_flags();
2238 	}
2239 |	for_start
2240 	    expression_opt T_SEMI
2241 	    expression_opt T_SEMI
2242 	    expression_opt T_RPAREN {
2243 		stmt_for_exprs($2, $4, $6);
2244 		clear_warning_flags();
2245 	}
2246 ;
2247 
2248 /* C99 6.8.6, C23 6.8.7.1 */
2249 jump_statement:
2250 	goto identifier T_SEMI {
2251 		stmt_goto(getsym($2));
2252 	}
2253 |	goto error T_SEMI {
2254 		set_sym_kind(SK_VCFT);
2255 	}
2256 |	T_CONTINUE T_SEMI {
2257 		stmt_continue();
2258 	}
2259 |	T_BREAK T_SEMI {
2260 		stmt_break();
2261 	}
2262 |	T_RETURN sys T_SEMI {
2263 		stmt_return($2, NULL);
2264 	}
2265 |	T_RETURN sys expression T_SEMI {
2266 		stmt_return($2, $3);
2267 	}
2268 ;
2269 
2270 goto:				/* see C99 6.8.6 */
2271 	T_GOTO {
2272 		set_sym_kind(SK_LABEL);
2273 	}
2274 ;
2275 
2276 asm_statement:			/* GCC extension */
2277 	T_ASM T_LPAREN read_until_rparen T_SEMI {
2278 		dcs_set_asm();
2279 	}
2280 |	T_ASM type_qualifier T_LPAREN read_until_rparen T_SEMI {
2281 		dcs_set_asm();
2282 	}
2283 |	T_ASM error
2284 ;
2285 
2286 read_until_rparen:		/* helper for 'asm_statement' */
2287 	/* empty */ {
2288 		read_until_rparen();
2289 	}
2290 ;
2291 
2292 /* C99 6.9, C23 6.9.1 */
2293 translation_unit:
2294 	external_declaration
2295 |	translation_unit external_declaration
2296 ;
2297 
2298 /* C99 6.9, C23 6.9.1 */
2299 external_declaration:
2300 	function_definition {
2301 		global_clean_up_decl(false);
2302 		clear_warning_flags();
2303 	}
2304 |	top_level_declaration {
2305 		global_clean_up_decl(false);
2306 		clear_warning_flags();
2307 	}
2308 |	asm_statement		/* GCC extension */
2309 |	T_SEMI {		/* GCC extension */
2310 		/*
2311 		 * TODO: Only allow this in GCC mode, not in plain C99.
2312 		 * This is one of the top 10 warnings in the NetBSD build.
2313 		 */
2314 		if (!allow_trad && !allow_c99)
2315 			/* empty declaration */
2316 			error(0);
2317 		else if (allow_c90)
2318 			/* empty declaration */
2319 			warning(0);
2320 	}
2321 ;
2322 
2323 /*
2324  * On the top level, lint allows several forms of declarations that it doesn't
2325  * allow in functions.  For example, a single ';' is an empty declaration and
2326  * is supported by some compilers, but in a function it would be an empty
2327  * statement, not a declaration.  This makes a difference in C90 mode, where
2328  * a statement must not be followed by a declaration.
2329  *
2330  * See 'declaration' for all other declarations.
2331  */
2332 top_level_declaration:		/* C99 6.9 calls this 'declaration' */
2333 	begin_type end_type notype_init_declarator_list T_SEMI {
2334 		/* TODO: Make this an error in C99 mode as well. */
2335 		if (!allow_trad && !allow_c99)
2336 			/* old-style declaration; add 'int' */
2337 			error(1);
2338 		else if (allow_c90)
2339 			/* old-style declaration; add 'int' */
2340 			warning(1);
2341 	}
2342 |	declaration
2343 |	error T_SEMI {
2344 		global_clean_up();
2345 	}
2346 |	error T_RBRACE {
2347 		global_clean_up();
2348 	}
2349 ;
2350 
2351 /* C99 6.9.1, C23 6.9.2 */
2352 function_definition:
2353 	func_declarator {
2354 		if ($1->s_type->t_tspec != FUNC) {
2355 			/* syntax error '%s' */
2356 			error(249, yytext);
2357 			YYERROR;
2358 		}
2359 		if ($1->s_type->t_typedef) {
2360 			/* ()-less function definition */
2361 			error(64);
2362 			YYERROR;
2363 		}
2364 		check_extern_declaration($1);
2365 		begin_function($1);
2366 		block_level++;
2367 		begin_declaration_level(DLK_OLD_STYLE_PARAMS);
2368 		if (lwarn == LWARN_NONE)
2369 			$1->s_used = true;
2370 	} arg_declaration_list_opt {
2371 		end_declaration_level();
2372 		block_level--;
2373 		check_func_lint_directives();
2374 		check_func_old_style_parameters();
2375 		begin_control_statement(CS_FUNCTION_BODY);
2376 	} compound_statement {
2377 		end_function();
2378 		end_control_statement(CS_FUNCTION_BODY);
2379 	}
2380 ;
2381 
2382 func_declarator:
2383 	begin_type end_type notype_declarator {
2384 		if (!allow_trad)
2385 			/* old-style declaration; add 'int' */
2386 			error(1);
2387 		$$ = $3;
2388 	}
2389 |	begin_type_declmods end_type notype_declarator {
2390 		if (!allow_trad)
2391 			/* old-style declaration; add 'int' */
2392 			error(1);
2393 		$$ = $3;
2394 	}
2395 |	begin_type_declaration_specifiers end_type type_declarator {
2396 		$$ = $3;
2397 	}
2398 ;
2399 
2400 arg_declaration_list_opt:	/* C99 6.9.1p13 example 1 */
2401 	/* empty */
2402 |	arg_declaration_list
2403 ;
2404 
2405 arg_declaration_list:		/* C99 6.9.1p13 example 1 */
2406 	arg_declaration
2407 |	arg_declaration_list arg_declaration
2408 	/* XXX or better "arg_declaration error" ? */
2409 |	error
2410 ;
2411 
2412 /*
2413  * "arg_declaration" is separated from "declaration" because it
2414  * needs other error handling.
2415  */
2416 arg_declaration:
2417 	begin_type_declmods end_type T_SEMI {
2418 		/* empty declaration */
2419 		warning(2);
2420 	}
2421 |	begin_type_declmods end_type notype_init_declarator_list T_SEMI
2422 |	begin_type_declaration_specifiers end_type T_SEMI {
2423 		if (!dcs->d_nonempty_decl)
2424 			/* empty declaration */
2425 			warning(2);
2426 		else
2427 			/* '%s' declared in parameter declaration list */
2428 			warning(3, type_name(dcs->d_type));
2429 	}
2430 |	begin_type_declaration_specifiers end_type
2431 	    type_init_declarator_list T_SEMI {
2432 		if (dcs->d_nonempty_decl)
2433 			/* '%s' declared in parameter declaration list */
2434 			warning(3, type_name(dcs->d_type));
2435 	}
2436 |	begin_type_declmods error
2437 |	begin_type_declaration_specifiers error
2438 ;
2439 
2440 /* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html */
2441 gcc_attribute_specifier_list_opt:
2442 	/* empty */
2443 |	gcc_attribute_specifier_list
2444 ;
2445 
2446 gcc_attribute_specifier_list:
2447 	gcc_attribute_specifier
2448 |	gcc_attribute_specifier_list gcc_attribute_specifier
2449 ;
2450 
2451 gcc_attribute_specifier:
2452 	T_ATTRIBUTE T_LPAREN T_LPAREN {
2453 		in_gcc_attribute = true;
2454 	} gcc_attribute_list {
2455 		in_gcc_attribute = false;
2456 	} T_RPAREN T_RPAREN
2457 ;
2458 
2459 gcc_attribute_list:
2460 	gcc_attribute
2461 |	gcc_attribute_list T_COMMA gcc_attribute
2462 ;
2463 
2464 gcc_attribute:
2465 	/* empty */
2466 |	T_NAME {
2467 		const char *name = $1->sb_name;
2468 		if (is_either(name, "packed", "__packed__"))
2469 			dcs_add_packed();
2470 		else if (is_either(name, "used", "__used__") ||
2471 		    is_either(name, "unused", "__unused__"))
2472 			dcs_set_used();
2473 		else if (is_either(name, "fallthrough", "__fallthrough__"))
2474 			suppress_fallthrough = true;
2475 	}
2476 |	T_NAME T_LPAREN T_RPAREN
2477 |	T_NAME T_LPAREN argument_expression_list T_RPAREN {
2478 		const char *name = $1->sb_name;
2479 		if (is_either(name, "aligned", "__aligned__")
2480 		    && $3->args_len == 1)
2481 			dcs_add_alignas($3->args[0]);
2482 	}
2483 |	type_qualifier {
2484 		if (!$1.tq_const)
2485 			yyerror("Bad attribute");
2486 	}
2487 ;
2488 
2489 /* The rule 'function_body' from C23 6.9.2 is inlined into 'function_definition'. */
2490 
2491 sys:
2492 	/* empty */ {
2493 		$$ = in_system_header;
2494 	}
2495 ;
2496 
2497 %%
2498 
2499 /* ARGSUSED */
2500 int
2501 yyerror(const char *msg)
2502 {
2503 	/* syntax error '%s' */
2504 	error(249, yytext);
2505 	if (++sytxerr >= 5)
2506 		norecover();
2507 	return 0;
2508 }
2509 
2510 #if YYDEBUG && YYBYACC
2511 static const char *
2512 cgram_to_string(int tok, YYSTYPE val)
2513 {
2514 
2515 	switch (tok) {
2516 	case T_INCDEC:
2517 		return val.y_inc ? "++" : "--";
2518 	case T_MULTIPLICATIVE:
2519 	case T_ADDITIVE:
2520 	case T_SHIFT:
2521 	case T_RELATIONAL:
2522 	case T_EQUALITY:
2523 	case T_OPASSIGN:
2524 		return op_name(val.y_op);
2525 	case T_SCLASS:
2526 		return scl_name(val.y_scl);
2527 	case T_TYPE:
2528 	case T_STRUCT_OR_UNION:
2529 		return tspec_name(val.y_tspec);
2530 	case T_QUAL:
2531 		return type_qualifiers_string(val.y_type_qualifiers);
2532 	case T_FUNCTION_SPECIFIER:
2533 		return function_specifier_name(val.y_function_specifier);
2534 	case T_NAME:
2535 		return val.y_name->sb_name;
2536 	default:
2537 		return "<none>";
2538 	}
2539 }
2540 #endif
2541 
2542 static void
2543 cgram_declare(sym_t *decl, bool has_initializer, sbuf_t *renaming)
2544 {
2545 	declare(decl, has_initializer, renaming);
2546 	if (renaming != NULL)
2547 		freeyyv(&renaming, T_NAME);
2548 }
2549 
2550 /*
2551  * Discard all input tokens up to and including the next unmatched right
2552  * parenthesis.
2553  */
2554 static void
2555 read_until_rparen(void)
2556 {
2557 	int level;
2558 
2559 	if (yychar < 0)
2560 		yychar = yylex();
2561 	freeyyv(&yylval, yychar);
2562 
2563 	level = 1;
2564 	while (yychar > 0) {
2565 		if (yychar == T_LPAREN)
2566 			level++;
2567 		if (yychar == T_RPAREN && --level == 0)
2568 			break;
2569 		freeyyv(&yylval, yychar = yylex());
2570 	}
2571 
2572 	yyclearin;
2573 }
2574 
2575 static balanced_token_sequence
2576 read_balanced_token_sequence(void)
2577 {
2578 	lint_assert(yychar < 0);
2579 	balanced_token_sequence seq = lex_balanced();
2580 	yyclearin;
2581 	return seq;
2582 }
2583 
2584 static sym_t *
2585 symbolrename(sym_t *s, sbuf_t *sb)
2586 {
2587 	if (sb != NULL)
2588 		s->s_rename = sb->sb_name;
2589 	return s;
2590 }
2591