• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Stupid C parser, version 1e-6.
3  *
4  * Let's see how hard this is to do.
5  *
6  * Copyright (C) 2003 Transmeta Corp.
7  *               2003-2004 Linus Torvalds
8  * Copyright (C) 2004 Christopher Li
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining a copy
11  * of this software and associated documentation files (the "Software"), to deal
12  * in the Software without restriction, including without limitation the rights
13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14  * copies of the Software, and to permit persons to whom the Software is
15  * furnished to do so, subject to the following conditions:
16  *
17  * The above copyright notice and this permission notice shall be included in
18  * all copies or substantial portions of the Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26  * THE SOFTWARE.
27  */
28 
29 #include <stdarg.h>
30 #include <stdlib.h>
31 #include <stdio.h>
32 #include <string.h>
33 #include <ctype.h>
34 #include <unistd.h>
35 #include <fcntl.h>
36 #include <limits.h>
37 
38 #include "lib.h"
39 #include "allocate.h"
40 #include "token.h"
41 #include "parse.h"
42 #include "symbol.h"
43 #include "scope.h"
44 #include "expression.h"
45 #include "target.h"
46 
47 static struct symbol_list **function_symbol_list;
48 struct symbol_list *function_computed_target_list;
49 struct statement_list *function_computed_goto_list;
50 
51 static struct token *statement(struct token *token, struct statement **tree);
52 static struct token *handle_attributes(struct token *token, struct decl_state *ctx);
53 
54 typedef struct token *declarator_t(struct token *, struct symbol *, struct decl_state *);
55 static declarator_t
56 	struct_specifier, union_specifier, enum_specifier,
57 	attribute_specifier, typeof_specifier,
58 	storage_specifier, thread_specifier;
59 static declarator_t generic_qualifier;
60 static declarator_t autotype_specifier;
61 
62 static struct token *parse_if_statement(struct token *token, struct statement *stmt);
63 static struct token *parse_return_statement(struct token *token, struct statement *stmt);
64 static struct token *parse_loop_iterator(struct token *token, struct statement *stmt);
65 static struct token *parse_default_statement(struct token *token, struct statement *stmt);
66 static struct token *parse_case_statement(struct token *token, struct statement *stmt);
67 static struct token *parse_switch_statement(struct token *token, struct statement *stmt);
68 static struct token *parse_for_statement(struct token *token, struct statement *stmt);
69 static struct token *parse_while_statement(struct token *token, struct statement *stmt);
70 static struct token *parse_do_statement(struct token *token, struct statement *stmt);
71 static struct token *parse_goto_statement(struct token *token, struct statement *stmt);
72 static struct token *parse_context_statement(struct token *token, struct statement *stmt);
73 static struct token *parse_range_statement(struct token *token, struct statement *stmt);
74 static struct token *parse_asm_statement(struct token *token, struct statement *stmt);
75 static struct token *toplevel_asm_declaration(struct token *token, struct symbol_list **list);
76 static struct token *parse_static_assert(struct token *token, struct symbol_list **unused);
77 
78 typedef struct token *attr_t(struct token *, struct symbol *,
79 			     struct decl_state *);
80 
81 static attr_t
82 	attribute_packed, attribute_aligned, attribute_modifier,
83 	attribute_function,
84 	attribute_bitwise,
85 	attribute_address_space, attribute_context,
86 	attribute_designated_init,
87 	attribute_transparent_union, ignore_attribute,
88 	attribute_mode, attribute_force;
89 
90 typedef struct symbol *to_mode_t(struct symbol *);
91 
92 static to_mode_t
93 	to_QI_mode, to_HI_mode, to_SI_mode, to_DI_mode, to_TI_mode;
94 static to_mode_t to_pointer_mode, to_word_mode;
95 
96 enum {
97 	Set_T = 1,
98 	Set_S = 2,
99 	Set_Char = 4,
100 	Set_Int = 8,
101 	Set_Double = 16,
102 	Set_Float = 32,
103 	Set_Signed = 64,
104 	Set_Unsigned = 128,
105 	Set_Short = 256,
106 	Set_Long = 512,
107 	Set_Vlong = 1024,
108 	Set_Int128 = 2048,
109 	Set_Any = Set_T | Set_Short | Set_Long | Set_Signed | Set_Unsigned
110 };
111 
112 enum {
113 	CInt = 0, CSInt, CUInt, CReal,
114 };
115 
asm_modifier(struct token * token,unsigned long * mods,unsigned long mod)116 static void asm_modifier(struct token *token, unsigned long *mods, unsigned long mod)
117 {
118 	if (*mods & mod)
119 		warning(token->pos, "duplicated asm modifier");
120 	*mods |= mod;
121 }
122 
123 static struct symbol_op typedef_op = {
124 	.type = KW_MODIFIER,
125 	.declarator = storage_specifier,
126 };
127 
128 static struct symbol_op inline_op = {
129 	.type = KW_MODIFIER,
130 	.declarator = generic_qualifier,
131 	.asm_modifier = asm_modifier,
132 };
133 
134 static struct symbol_op noreturn_op = {
135 	.type = KW_MODIFIER,
136 	.declarator = generic_qualifier,
137 };
138 
139 static declarator_t alignas_specifier;
140 static struct symbol_op alignas_op = {
141 	.type = KW_MODIFIER,
142 	.declarator = alignas_specifier,
143 };
144 
145 static struct symbol_op auto_op = {
146 	.type = KW_MODIFIER,
147 	.declarator = storage_specifier,
148 };
149 
150 static struct symbol_op register_op = {
151 	.type = KW_MODIFIER,
152 	.declarator = storage_specifier,
153 };
154 
155 static struct symbol_op static_op = {
156 	.type = KW_MODIFIER|KW_STATIC,
157 	.declarator = storage_specifier,
158 };
159 
160 static struct symbol_op extern_op = {
161 	.type = KW_MODIFIER,
162 	.declarator = storage_specifier,
163 };
164 
165 static struct symbol_op thread_op = {
166 	.type = KW_MODIFIER,
167 	.declarator = thread_specifier,
168 };
169 
170 static struct symbol_op const_op = {
171 	.type = KW_QUALIFIER,
172 	.declarator = generic_qualifier,
173 };
174 
175 static struct symbol_op volatile_op = {
176 	.type = KW_QUALIFIER,
177 	.declarator = generic_qualifier,
178 	.asm_modifier = asm_modifier,
179 };
180 
181 static struct symbol_op restrict_op = {
182 	.type = KW_QUALIFIER,
183 	.declarator = generic_qualifier,
184 };
185 
186 static struct symbol_op atomic_op = {
187 	.type = KW_QUALIFIER,
188 	.declarator = generic_qualifier,
189 };
190 
191 static struct symbol_op typeof_op = {
192 	.type = KW_SPECIFIER,
193 	.declarator = typeof_specifier,
194 	.test = Set_Any,
195 	.set = Set_S|Set_T,
196 };
197 
198 static struct symbol_op autotype_op = {
199 	.type = KW_SPECIFIER,
200 	.declarator = autotype_specifier,
201 	.test = Set_Any,
202 	.set = Set_S|Set_T,
203 };
204 
205 static struct symbol_op attribute_op = {
206 	.type = KW_ATTRIBUTE,
207 	.declarator = attribute_specifier,
208 };
209 
210 static struct symbol_op struct_op = {
211 	.type = KW_SPECIFIER,
212 	.declarator = struct_specifier,
213 	.test = Set_Any,
214 	.set = Set_S|Set_T,
215 };
216 
217 static struct symbol_op union_op = {
218 	.type = KW_SPECIFIER,
219 	.declarator = union_specifier,
220 	.test = Set_Any,
221 	.set = Set_S|Set_T,
222 };
223 
224 static struct symbol_op enum_op = {
225 	.type = KW_SPECIFIER,
226 	.declarator = enum_specifier,
227 	.test = Set_Any,
228 	.set = Set_S|Set_T,
229 };
230 
231 static struct symbol_op spec_op = {
232 	.type = KW_SPECIFIER | KW_EXACT,
233 	.test = Set_Any,
234 	.set = Set_S|Set_T,
235 };
236 
237 static struct symbol_op char_op = {
238 	.type = KW_SPECIFIER,
239 	.test = Set_T|Set_Long|Set_Short,
240 	.set = Set_T|Set_Char,
241 	.class = CInt,
242 };
243 
244 static struct symbol_op int_op = {
245 	.type = KW_SPECIFIER,
246 	.test = Set_T,
247 	.set = Set_T|Set_Int,
248 };
249 
250 static struct symbol_op double_op = {
251 	.type = KW_SPECIFIER,
252 	.test = Set_T|Set_Signed|Set_Unsigned|Set_Short|Set_Vlong,
253 	.set = Set_T|Set_Double,
254 	.class = CReal,
255 };
256 
257 static struct symbol_op float_op = {
258 	.type = KW_SPECIFIER,
259 	.test = Set_T|Set_Signed|Set_Unsigned|Set_Short|Set_Long,
260 	.set = Set_T|Set_Float,
261 	.class = CReal,
262 };
263 
264 static struct symbol_op short_op = {
265 	.type = KW_SPECIFIER,
266 	.test = Set_S|Set_Char|Set_Float|Set_Double|Set_Long|Set_Short,
267 	.set = Set_Short,
268 };
269 
270 static struct symbol_op signed_op = {
271 	.type = KW_SPECIFIER,
272 	.test = Set_S|Set_Float|Set_Double|Set_Signed|Set_Unsigned,
273 	.set = Set_Signed,
274 	.class = CSInt,
275 };
276 
277 static struct symbol_op unsigned_op = {
278 	.type = KW_SPECIFIER,
279 	.test = Set_S|Set_Float|Set_Double|Set_Signed|Set_Unsigned,
280 	.set = Set_Unsigned,
281 	.class = CUInt,
282 };
283 
284 static struct symbol_op long_op = {
285 	.type = KW_SPECIFIER,
286 	.test = Set_S|Set_Char|Set_Float|Set_Short|Set_Vlong,
287 	.set = Set_Long,
288 };
289 
290 static struct symbol_op int128_op = {
291 	.type = KW_SPECIFIER,
292 	.test = Set_S|Set_T|Set_Char|Set_Short|Set_Int|Set_Float|Set_Double|Set_Long|Set_Vlong|Set_Int128,
293 	.set =  Set_T|Set_Int128|Set_Vlong,
294 	.class = CInt,
295 };
296 
297 static struct symbol_op if_op = {
298 	.statement = parse_if_statement,
299 };
300 
301 static struct symbol_op return_op = {
302 	.statement = parse_return_statement,
303 };
304 
305 static struct symbol_op loop_iter_op = {
306 	.statement = parse_loop_iterator,
307 };
308 
309 static struct symbol_op default_op = {
310 	.statement = parse_default_statement,
311 };
312 
313 static struct symbol_op case_op = {
314 	.statement = parse_case_statement,
315 };
316 
317 static struct symbol_op switch_op = {
318 	.statement = parse_switch_statement,
319 };
320 
321 static struct symbol_op for_op = {
322 	.statement = parse_for_statement,
323 };
324 
325 static struct symbol_op while_op = {
326 	.statement = parse_while_statement,
327 };
328 
329 static struct symbol_op do_op = {
330 	.statement = parse_do_statement,
331 };
332 
333 static struct symbol_op goto_op = {
334 	.statement = parse_goto_statement,
335 };
336 
337 static struct symbol_op __context___op = {
338 	.statement = parse_context_statement,
339 	.attribute = attribute_context,
340 };
341 
342 static struct symbol_op range_op = {
343 	.statement = parse_range_statement,
344 };
345 
346 static struct symbol_op asm_op = {
347 	.type = KW_ASM,
348 	.statement = parse_asm_statement,
349 	.toplevel = toplevel_asm_declaration,
350 };
351 
352 static struct symbol_op static_assert_op = {
353 	.toplevel = parse_static_assert,
354 };
355 
356 static struct symbol_op packed_op = {
357 	.attribute = attribute_packed,
358 };
359 
360 static struct symbol_op aligned_op = {
361 	.attribute = attribute_aligned,
362 };
363 
364 static struct symbol_op attr_mod_op = {
365 	.attribute = attribute_modifier,
366 };
367 
368 static struct symbol_op attr_fun_op = {
369 	.attribute = attribute_function,
370 };
371 
372 static struct symbol_op attr_bitwise_op = {
373 	.attribute = attribute_bitwise,
374 };
375 
376 static struct symbol_op attr_force_op = {
377 	.attribute = attribute_force,
378 };
379 
380 static struct symbol_op address_space_op = {
381 	.attribute = attribute_address_space,
382 };
383 
384 static struct symbol_op mode_op = {
385 	.attribute = attribute_mode,
386 };
387 
388 static struct symbol_op context_op = {
389 	.attribute = attribute_context,
390 };
391 
392 static struct symbol_op designated_init_op = {
393 	.attribute = attribute_designated_init,
394 };
395 
396 static struct symbol_op transparent_union_op = {
397 	.attribute = attribute_transparent_union,
398 };
399 
400 static struct symbol_op ignore_attr_op = {
401 	.attribute = ignore_attribute,
402 };
403 
404 static struct symbol_op mode_QI_op = {
405 	.type = KW_MODE,
406 	.to_mode = to_QI_mode
407 };
408 
409 static struct symbol_op mode_HI_op = {
410 	.type = KW_MODE,
411 	.to_mode = to_HI_mode
412 };
413 
414 static struct symbol_op mode_SI_op = {
415 	.type = KW_MODE,
416 	.to_mode = to_SI_mode
417 };
418 
419 static struct symbol_op mode_DI_op = {
420 	.type = KW_MODE,
421 	.to_mode = to_DI_mode
422 };
423 
424 static struct symbol_op mode_TI_op = {
425 	.type = KW_MODE,
426 	.to_mode = to_TI_mode
427 };
428 
429 static struct symbol_op mode_pointer_op = {
430 	.type = KW_MODE,
431 	.to_mode = to_pointer_mode
432 };
433 
434 static struct symbol_op mode_word_op = {
435 	.type = KW_MODE,
436 	.to_mode = to_word_mode
437 };
438 
439 /*
440  * Define the keyword and their effects.
441  * The entries in the 'typedef' and put in NS_TYPEDEF and
442  * are automatically set as reserved keyword while the ones
443  * in the 'keyword' table are just put in NS_KEYWORD.
444  *
445  * The entries are added via the 3 macros:
446  *   N() for entries with "name" only,
447  *   D() for entries with "name" & "__name__",
448  *   A() for entries with "name", "__name" & "__name__",
449  *   U() for entries with "__name" & "__name__".
450  */
451 static struct init_keyword {
452 	const char *name;
453 	struct symbol_op *op;
454 	struct symbol *type;
455 	unsigned long mods;
456 } typedefs[] = {
457 #define N(I, O,...)	{ I, O,##__VA_ARGS__ }
458 #define D(I, O,...)	N(I,O,##__VA_ARGS__ ),		\
459 			N("__" I "__",O,##__VA_ARGS__)
460 #define A(I, O,...)	N(I,O,##__VA_ARGS__ ),		\
461 			N("__" I,O,##__VA_ARGS__),	\
462 			N("__" I "__",O,##__VA_ARGS__)
463 #define U(I, O,...)	N("__" I,O,##__VA_ARGS__),	\
464 			N("__" I "__",O,##__VA_ARGS__)
465 	/* Storage classes */
466 	N("auto",		&auto_op,	.mods = MOD_AUTO),
467 	N("register",		&register_op,	.mods = MOD_REGISTER),
468 	N("static",		&static_op,	.mods = MOD_STATIC),
469 	N("extern",		&extern_op,	.mods = MOD_EXTERN),
470 	N("__thread",		&thread_op),
471 	N("_Thread_local",	&thread_op),
472 
473 	A("inline",		&inline_op,	.mods = MOD_INLINE),
474 
475 	/* Typedef ... */
476 	N("typedef",		&typedef_op,	.mods = MOD_USERTYPE),
477 	A("typeof",		&typeof_op),
478 	N("__auto_type",	&autotype_op),
479 
480 	/* Type qualifiers */
481 	A("const",		&const_op,	.mods = MOD_CONST),
482 	A("volatile",		&volatile_op,	.mods = MOD_VOLATILE),
483 	A("restrict",		&restrict_op,	.mods = MOD_RESTRICT),
484 
485 	N("_Atomic",		&atomic_op,	.mods = MOD_ATOMIC),
486 	N("_Noreturn",		&noreturn_op,	.mods = MOD_NORETURN),
487 	N("_Alignas",		&alignas_op),
488 
489 	U("attribute",		&attribute_op),
490 
491 	/* Type specifiers */
492 	N("struct",		&struct_op),
493 	N("union",		&union_op),
494 	N("enum",		&enum_op),
495 
496 	N("void",		&spec_op,	.type = &void_ctype),
497 	N("char",		&char_op),
498 	N("short",		&short_op),
499 	N("int",		&int_op),
500 	N("long",		&long_op),
501 	N("float",		&float_op),
502 	N("double",		&double_op),
503 	A("signed",		&signed_op),
504 	N("unsigned",		&unsigned_op),
505 	N("__int128",		&int128_op),
506 	N("_Bool",		&spec_op,	.type = &bool_ctype),
507 
508 	/* Predeclared types */
509 	N("__builtin_va_list",	&spec_op,	.type = &ptr_ctype),
510 	N("__builtin_ms_va_list",&spec_op,	.type = &ptr_ctype),
511 	N("__int128_t",		&spec_op,	.type = &sint128_ctype),
512 	N("__uint128_t",	&spec_op,	.type = &uint128_ctype),
513 	N("_Float32",		&spec_op,	.type = &float32_ctype),
514 	N("_Float32x",		&spec_op,	.type = &float32x_ctype),
515 	N("_Float64",		&spec_op,	.type = &float64_ctype),
516 	N("_Float64x",		&spec_op,	.type = &float64x_ctype),
517 	N("_Float128",		&spec_op,	.type = &float128_ctype),
518 }, keywords[] = {
519 	/* Statements */
520 	N("if",			&if_op),
521 	N("return",		&return_op),
522 	N("break",		&loop_iter_op),
523 	N("continue",		&loop_iter_op),
524 	N("default",		&default_op),
525 	N("case",		&case_op),
526 	N("switch",		&switch_op),
527 	N("for",		&for_op),
528 	N("while",		&while_op),
529 	N("do",			&do_op),
530 	N("goto",		&goto_op),
531 	A("asm",		&asm_op),
532 	N("context",		&context_op),
533 	N("__context__",	&__context___op),
534 	N("__range__",		&range_op),
535 	N("_Static_assert",	&static_assert_op),
536 
537 	/* Attributes */
538 	D("packed",		&packed_op),
539 	D("aligned",		&aligned_op),
540 	D("nocast",		&attr_mod_op,		.mods = MOD_NOCAST),
541 	D("noderef",		&attr_mod_op,		.mods = MOD_NODEREF),
542 	D("safe",		&attr_mod_op,		.mods = MOD_SAFE),
543 	D("unused",		&attr_mod_op,		.mods = MOD_UNUSED),
544 	D("externally_visible",	&attr_mod_op,		.mods = MOD_EXT_VISIBLE),
545 	D("force",		&attr_force_op),
546 	D("bitwise",		&attr_bitwise_op,	.mods = MOD_BITWISE),
547 	D("address_space",	&address_space_op),
548 	D("designated_init",	&designated_init_op),
549 	D("transparent_union",	&transparent_union_op),
550 	D("noreturn",		&attr_fun_op,		.mods = MOD_NORETURN),
551 	D("pure",		&attr_fun_op,		.mods = MOD_PURE),
552 	A("const",		&attr_fun_op,		.mods = MOD_PURE),
553 	D("gnu_inline",		&attr_fun_op,		.mods = MOD_GNU_INLINE),
554 
555 	/* Modes */
556 	D("mode",		&mode_op),
557 	D("QI",			&mode_QI_op),
558 	D("HI",			&mode_HI_op),
559 	D("SI",			&mode_SI_op),
560 	D("DI",			&mode_DI_op),
561 	D("TI",			&mode_TI_op),
562 	D("byte",		&mode_QI_op),
563 	D("pointer",		&mode_pointer_op),
564 	D("word",		&mode_word_op),
565 };
566 
567 
568 static const char *ignored_attributes[] = {
569 
570 #define GCC_ATTR(x)		\
571 	STRINGIFY(x), 		\
572 	STRINGIFY(__##x##__),
573 
574 #include "gcc-attr-list.h"
575 
576 #undef GCC_ATTR
577 
578 	"bounded",
579 	"__bounded__",
580 	"__noclone",
581 	"__nonnull",
582 	"__nothrow",
583 };
584 
585 
init_keyword(int stream,struct init_keyword * kw,enum namespace ns)586 static void init_keyword(int stream, struct init_keyword *kw, enum namespace ns)
587 {
588 	struct symbol *sym = create_symbol(stream, kw->name, SYM_KEYWORD, ns);
589 	sym->ident->keyword = 1;
590 	sym->ident->reserved |= (ns == NS_TYPEDEF);
591 	sym->ctype.modifiers = kw->mods;
592 	sym->ctype.base_type = kw->type;
593 	sym->op = kw->op;
594 }
595 
init_parser(int stream)596 void init_parser(int stream)
597 {
598 	int i;
599 
600 	for (i = 0; i < ARRAY_SIZE(typedefs); i++)
601 		init_keyword(stream, &typedefs[i], NS_TYPEDEF);
602 	for (i = 0; i < ARRAY_SIZE(keywords); i++)
603 		init_keyword(stream, &keywords[i], NS_KEYWORD);
604 
605 	for (i = 0; i < ARRAY_SIZE(ignored_attributes); i++) {
606 		const char * name = ignored_attributes[i];
607 		struct symbol *sym = create_symbol(stream, name, SYM_KEYWORD,
608 						   NS_KEYWORD);
609 		if (!sym->op) {
610 			sym->ident->keyword = 1;
611 			sym->op = &ignore_attr_op;
612 		}
613 	}
614 }
615 
616 
skip_to(struct token * token,int op)617 static struct token *skip_to(struct token *token, int op)
618 {
619 	while (!match_op(token, op) && !eof_token(token))
620 		token = token->next;
621 	return token;
622 }
623 
624 static struct token bad_token = { .pos.type = TOKEN_BAD };
expect(struct token * token,int op,const char * where)625 struct token *expect(struct token *token, int op, const char *where)
626 {
627 	if (!match_op(token, op)) {
628 		if (token != &bad_token) {
629 			bad_token.next = token;
630 			sparse_error(token->pos, "Expected %s %s", show_special(op), where);
631 			sparse_error(token->pos, "got %s", show_token(token));
632 		}
633 		if (op == ';')
634 			return skip_to(token, op);
635 		return &bad_token;
636 	}
637 	return token->next;
638 }
639 
640 ///
641 // issue an error message on new parsing errors
642 // @token: the current token
643 // @errmsg: the error message
644 // If the current token is from a previous error, an error message
645 // has already been issued, so nothing more is done.
646 // Otherwise, @errmsg is displayed followed by the current token.
unexpected(struct token * token,const char * errmsg)647 static void unexpected(struct token *token, const char *errmsg)
648 {
649 	if (token == &bad_token)
650 		return;
651 	sparse_error(token->pos, "%s", errmsg);
652 	sparse_error(token->pos, "got %s", show_token(token));
653 }
654 
655 // Add a symbol to the list of function-local symbols
fn_local_symbol(struct symbol * sym)656 static void fn_local_symbol(struct symbol *sym)
657 {
658 	if (function_symbol_list)
659 		add_symbol(function_symbol_list, sym);
660 }
661 
alloc_statement(struct position pos,int type)662 struct statement *alloc_statement(struct position pos, int type)
663 {
664 	struct statement *stmt = __alloc_statement(0);
665 	stmt->type = type;
666 	stmt->pos = pos;
667 	return stmt;
668 }
669 
670 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list);
671 
672 static void apply_ctype(struct position pos, struct ctype *dst, struct ctype *src);
673 
apply_modifiers(struct position pos,struct decl_state * ctx)674 static void apply_modifiers(struct position pos, struct decl_state *ctx)
675 {
676 	struct symbol *ctype;
677 	if (!ctx->mode)
678 		return;
679 	ctype = ctx->mode->to_mode(ctx->ctype.base_type);
680 	if (!ctype)
681 		sparse_error(pos, "don't know how to apply mode to %s",
682 				show_typename(ctx->ctype.base_type));
683 	else
684 		ctx->ctype.base_type = ctype;
685 
686 }
687 
alloc_indirect_symbol(struct position pos,struct ctype * ctype,int type)688 static struct symbol * alloc_indirect_symbol(struct position pos, struct ctype *ctype, int type)
689 {
690 	struct symbol *sym = alloc_symbol(pos, type);
691 
692 	sym->ctype.base_type = ctype->base_type;
693 	sym->ctype.modifiers = ctype->modifiers;
694 
695 	ctype->base_type = sym;
696 	ctype->modifiers = 0;
697 	return sym;
698 }
699 
700 /*
701  * NOTE! NS_LABEL is not just a different namespace,
702  * it also ends up using function scope instead of the
703  * regular symbol scope.
704  */
label_symbol(struct token * token,int used)705 struct symbol *label_symbol(struct token *token, int used)
706 {
707 	struct symbol *sym = lookup_symbol(token->ident, NS_LABEL);
708 	if (!sym) {
709 		sym = alloc_symbol(token->pos, SYM_LABEL);
710 		bind_symbol(sym, token->ident, NS_LABEL);
711 		if (used)
712 			sym->used = 1;
713 		fn_local_symbol(sym);
714 	}
715 	return sym;
716 }
717 
struct_union_enum_specifier(enum type type,struct token * token,struct decl_state * ctx,struct token * (* parse)(struct token *,struct symbol *))718 static struct token *struct_union_enum_specifier(enum type type,
719 	struct token *token, struct decl_state *ctx,
720 	struct token *(*parse)(struct token *, struct symbol *))
721 {
722 	struct decl_state attr = { };
723 	struct symbol *sym;
724 	struct position *repos;
725 
726 	token = handle_attributes(token, &attr);
727 	if (token_type(token) == TOKEN_IDENT) {
728 		sym = lookup_symbol(token->ident, NS_STRUCT);
729 		if (!sym ||
730 		    (is_outer_scope(sym->scope) &&
731 		     (match_op(token->next,';') || match_op(token->next,'{')))) {
732 			// Either a new symbol, or else an out-of-scope
733 			// symbol being redefined.
734 			sym = alloc_symbol(token->pos, type);
735 			bind_symbol(sym, token->ident, NS_STRUCT);
736 		}
737 		if (sym->type != type)
738 			error_die(token->pos, "invalid tag applied to %s", show_typename (sym));
739 		ctx->ctype.base_type = sym;
740 		repos = &token->pos;
741 		token = token->next;
742 		if (!match_op(token, '{'))
743 			return token;
744 
745 		// The following test is actually wrong for empty
746 		// structs, but (1) they are not C99, (2) gcc does
747 		// the same thing, and (3) it's easier.
748 		if (sym->symbol_list)
749 			error_die(token->pos, "redefinition of %s", show_typename (sym));
750 		sym->pos = *repos;
751 
752 		// Mark the structure as needing re-examination
753 		sym->examined = 0;
754 	} else if (match_op(token, '{')) {
755 		// private struct/union/enum type
756 		sym = alloc_symbol(token->pos, type);
757 		set_current_scope(sym);		// used by dissect
758 		ctx->ctype.base_type = sym;
759 	} else {
760 		sparse_error(token->pos, "expected declaration");
761 		ctx->ctype.base_type = &bad_ctype;
762 		return token;
763 	}
764 
765 	token = parse(token->next, sym);
766 	token = expect(token, '}', "at end of specifier");
767 	attr.ctype.base_type = sym;
768 	token = handle_attributes(token, &attr);
769 	apply_ctype(token->pos, &sym->ctype, &attr.ctype);
770 	sym->packed = attr.packed;
771 
772 	sym->endpos = token->pos;
773 
774 	return token;
775 }
776 
parse_struct_declaration(struct token * token,struct symbol * sym)777 static struct token *parse_struct_declaration(struct token *token, struct symbol *sym)
778 {
779 	struct symbol *field, *last = NULL;
780 	struct token *res;
781 	res = struct_declaration_list(token, &sym->symbol_list);
782 	FOR_EACH_PTR(sym->symbol_list, field) {
783 		if (!field->ident) {
784 			struct symbol *base = field->ctype.base_type;
785 			if (base && base->type == SYM_BITFIELD)
786 				continue;
787 		}
788 		if (last)
789 			last->next_subobject = field;
790 		last = field;
791 	} END_FOR_EACH_PTR(field);
792 	return res;
793 }
794 
parse_union_declaration(struct token * token,struct symbol * sym)795 static struct token *parse_union_declaration(struct token *token, struct symbol *sym)
796 {
797 	return struct_declaration_list(token, &sym->symbol_list);
798 }
799 
struct_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)800 static struct token *struct_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
801 {
802 	return struct_union_enum_specifier(SYM_STRUCT, token, ctx, parse_struct_declaration);
803 }
804 
union_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)805 static struct token *union_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
806 {
807 	return struct_union_enum_specifier(SYM_UNION, token, ctx, parse_union_declaration);
808 }
809 
810 ///
811 // safe right shift
812 //
813 // This allow to use a shift amount as big (or bigger)
814 // than the width of the value to be shifted, in which case
815 // the result is, of course, 0.
rshift(unsigned long long val,unsigned int n)816 static unsigned long long rshift(unsigned long long val, unsigned int n)
817 {
818 	if (n >= (sizeof(val) * 8))
819 		return 0;
820 	return val >> n;
821 }
822 
823 struct range {
824 	long long		neg;
825 	unsigned long long	pos;
826 };
827 
update_range(struct range * range,unsigned long long uval,struct symbol * vtype)828 static void update_range(struct range *range, unsigned long long uval, struct symbol *vtype)
829 {
830 	long long sval = uval;
831 
832 	if (is_signed_type(vtype) && (sval < 0)) {
833 		if (sval < range->neg)
834 			range->neg = sval;
835 	} else {
836 		if (uval > range->pos)
837 			range->pos = uval;
838 	}
839 }
840 
type_is_ok(struct symbol * type,struct range range)841 static int type_is_ok(struct symbol *type, struct range range)
842 {
843 	int shift = type->bit_size;
844 	int is_unsigned = type->ctype.modifiers & MOD_UNSIGNED;
845 
846 	if (!is_unsigned)
847 		shift--;
848 	if (rshift(range.pos, shift))
849 		return 0;
850 	if (range.neg == 0)
851 		return 1;
852 	if (is_unsigned)
853 		return 0;
854 	if (rshift(~range.neg, shift))
855 		return 0;
856 	return 1;
857 }
858 
type_range(struct symbol * type)859 static struct range type_range(struct symbol *type)
860 {
861 	struct range range;
862 	unsigned int size = type->bit_size;
863 	unsigned long long max;
864 	long long min;
865 
866 	if (is_signed_type(type)) {
867 		min = sign_bit(size);
868 		max = min - 1;
869 	} else {
870 		min = 0;
871 		max = bits_mask(size);
872 	}
873 
874 	range.pos = max;
875 	range.neg = min;
876 	return range;
877 }
878 
val_in_range(struct range * range,long long sval,struct symbol * vtype)879 static int val_in_range(struct range *range, long long sval, struct symbol *vtype)
880 {
881 	unsigned long long uval = sval;
882 
883 	if (is_signed_type(vtype) && (sval < 0))
884 		return range->neg <= sval;
885 	else
886 		return uval <= range->pos;
887 }
888 
cast_enum_list(struct symbol_list * list,struct symbol * base_type)889 static void cast_enum_list(struct symbol_list *list, struct symbol *base_type)
890 {
891 	struct range irange = type_range(&int_ctype);
892 	struct symbol *sym;
893 
894 	FOR_EACH_PTR(list, sym) {
895 		struct expression *expr = sym->initializer;
896 		struct symbol *ctype;
897 		long long val;
898 		if (expr->type != EXPR_VALUE)
899 			continue;
900 		ctype = expr->ctype;
901 		val = get_expression_value(expr);
902 		if (is_int_type(ctype) && val_in_range(&irange, val, ctype)) {
903 			expr->ctype = &int_ctype;
904 			continue;
905 		}
906 		cast_value(expr, base_type, expr, ctype);
907 		expr->ctype = base_type;
908 	} END_FOR_EACH_PTR(sym);
909 }
910 
parse_enum_declaration(struct token * token,struct symbol * parent)911 static struct token *parse_enum_declaration(struct token *token, struct symbol *parent)
912 {
913 	unsigned long long lastval = 0;
914 	struct symbol *ctype = NULL, *base_type = NULL;
915 	struct range range = { };
916 	int mix_bitwise = 0;
917 
918 	parent->examined = 1;
919 	parent->ctype.base_type = &int_ctype;
920 	while (token_type(token) == TOKEN_IDENT) {
921 		struct expression *expr = NULL;
922 		struct token *next = token->next;
923 		struct decl_state ctx = { };
924 		struct symbol *sym;
925 
926 		// FIXME: only 'deprecated' should be accepted
927 		next = handle_attributes(next, &ctx);
928 
929 		if (match_op(next, '=')) {
930 			next = constant_expression(next->next, &expr);
931 			lastval = get_expression_value(expr);
932 			ctype = &void_ctype;
933 			if (expr && expr->ctype)
934 				ctype = expr->ctype;
935 		} else if (!ctype) {
936 			ctype = &int_ctype;
937 		} else if (is_int_type(ctype)) {
938 			lastval++;
939 		} else {
940 			error_die(token->pos, "can't increment the last enum member");
941 		}
942 
943 		if (!expr) {
944 			expr = alloc_expression(token->pos, EXPR_VALUE);
945 			expr->value = lastval;
946 			expr->ctype = ctype;
947 		}
948 
949 		sym = alloc_symbol(token->pos, SYM_NODE);
950 		bind_symbol(sym, token->ident, NS_SYMBOL);
951 		sym->ctype.modifiers &= ~MOD_ADDRESSABLE;
952 		sym->initializer = expr;
953 		sym->enum_member = 1;
954 		sym->ctype.base_type = parent;
955 		add_ptr_list(&parent->symbol_list, sym);
956 
957 		if (base_type != &bad_ctype) {
958 			if (ctype->type == SYM_NODE)
959 				ctype = ctype->ctype.base_type;
960 			if (ctype->type == SYM_ENUM) {
961 				if (ctype == parent)
962 					ctype = base_type;
963 				else
964 					ctype = ctype->ctype.base_type;
965 			}
966 			/*
967 			 * base_type rules:
968 			 *  - if all enums are of the same type, then
969 			 *    the base_type is that type (two first
970 			 *    cases)
971 			 *  - if enums are of different types, they
972 			 *    all have to be integer types, and the
973 			 *    base type is at least "int_ctype".
974 			 *  - otherwise the base_type is "bad_ctype".
975 			 */
976 			if (!base_type || ctype == &bad_ctype) {
977 				base_type = ctype;
978 			} else if (ctype == base_type) {
979 				/* nothing */
980 			} else if (is_int_type(base_type) && is_int_type(ctype)) {
981 				base_type = &int_ctype;
982 			} else if (is_restricted_type(base_type) != is_restricted_type(ctype)) {
983 				if (!mix_bitwise++) {
984 					warning(expr->pos, "mixed bitwiseness");
985 				}
986 			} else if (is_restricted_type(base_type) && base_type != ctype) {
987 				sparse_error(expr->pos, "incompatible restricted type");
988 				info(expr->pos, "   expected: %s", show_typename(base_type));
989 				info(expr->pos, "        got: %s", show_typename(ctype));
990 				base_type = &bad_ctype;
991 			} else if (base_type != &bad_ctype) {
992 				sparse_error(token->pos, "bad enum definition");
993 				base_type = &bad_ctype;
994 			}
995 			parent->ctype.base_type = base_type;
996 		}
997 		if (is_int_type(base_type)) {
998 			update_range(&range, lastval, ctype);
999 		}
1000 		token = next;
1001 
1002 		sym->endpos = token->pos;
1003 
1004 		if (!match_op(token, ','))
1005 			break;
1006 		token = token->next;
1007 	}
1008 	if (!base_type) {
1009 		sparse_error(token->pos, "empty enum definition");
1010 		base_type = &bad_ctype;
1011 	}
1012 	else if (!is_int_type(base_type))
1013 		;
1014 	else if (type_is_ok(&uint_ctype, range))
1015 		base_type = &uint_ctype;
1016 	else if (type_is_ok(&int_ctype, range))
1017 		base_type = &int_ctype;
1018 	else if (type_is_ok(&ulong_ctype, range))
1019 		base_type = &ulong_ctype;
1020 	else if (type_is_ok(&long_ctype, range))
1021 		base_type = &long_ctype;
1022 	else if (type_is_ok(&ullong_ctype, range))
1023 		base_type = &ullong_ctype;
1024 	else if (type_is_ok(&llong_ctype, range))
1025 		base_type = &llong_ctype;
1026 	else
1027 		base_type = &bad_ctype;
1028 	parent->ctype.base_type = base_type;
1029 	parent->ctype.modifiers |= (base_type->ctype.modifiers & MOD_UNSIGNED);
1030 	parent->examined = 0;
1031 
1032 	if (mix_bitwise)
1033 		return token;
1034 	cast_enum_list(parent->symbol_list, base_type);
1035 
1036 	return token;
1037 }
1038 
enum_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)1039 static struct token *enum_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
1040 {
1041 	struct token *ret = struct_union_enum_specifier(SYM_ENUM, token, ctx, parse_enum_declaration);
1042 	struct ctype *ctype = &ctx->ctype.base_type->ctype;
1043 
1044 	if (!ctype->base_type)
1045 		ctype->base_type = &incomplete_ctype;
1046 
1047 	return ret;
1048 }
1049 
typeof_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)1050 static struct token *typeof_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
1051 {
1052 
1053 	if (!match_op(token, '(')) {
1054 		sparse_error(token->pos, "expected '(' after typeof");
1055 		return token;
1056 	}
1057 	if (lookup_type(token->next)) {
1058 		struct symbol *sym;
1059 		token = typename(token->next, &sym, NULL);
1060 		ctx->ctype.base_type = sym->ctype.base_type;
1061 		apply_ctype(token->pos, &ctx->ctype, &sym->ctype);
1062 	} else {
1063 		struct symbol *typeof_sym = alloc_symbol(token->pos, SYM_TYPEOF);
1064 		token = parse_expression(token->next, &typeof_sym->initializer);
1065 
1066 		typeof_sym->endpos = token->pos;
1067 		if (!typeof_sym->initializer) {
1068 			sparse_error(token->pos, "expected expression after the '(' token");
1069 			typeof_sym = &bad_ctype;
1070 		}
1071 		ctx->ctype.base_type = typeof_sym;
1072 	}
1073 	return expect(token, ')', "after typeof");
1074 }
1075 
autotype_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)1076 static struct token *autotype_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
1077 {
1078 	ctx->ctype.base_type = &autotype_ctype;
1079 	ctx->autotype = 1;
1080 	return token;
1081 }
1082 
ignore_attribute(struct token * token,struct symbol * attr,struct decl_state * ctx)1083 static struct token *ignore_attribute(struct token *token, struct symbol *attr, struct decl_state *ctx)
1084 {
1085 	struct expression *expr = NULL;
1086 	if (match_op(token, '('))
1087 		token = parens_expression(token, &expr, "in attribute");
1088 	return token;
1089 }
1090 
attribute_packed(struct token * token,struct symbol * attr,struct decl_state * ctx)1091 static struct token *attribute_packed(struct token *token, struct symbol *attr, struct decl_state *ctx)
1092 {
1093 	if (!ctx->ctype.alignment) {
1094 		ctx->ctype.alignment = 1;
1095 		ctx->packed = 1;
1096 	}
1097 	return token;
1098 }
1099 
attribute_aligned(struct token * token,struct symbol * attr,struct decl_state * ctx)1100 static struct token *attribute_aligned(struct token *token, struct symbol *attr, struct decl_state *ctx)
1101 {
1102 	int alignment = max_alignment;
1103 	struct expression *expr = NULL;
1104 
1105 	if (match_op(token, '(')) {
1106 		token = parens_expression(token, &expr, "in attribute");
1107 		if (expr)
1108 			alignment = const_expression_value(expr);
1109 	}
1110 	if (alignment & (alignment-1)) {
1111 		warning(token->pos, "I don't like non-power-of-2 alignments");
1112 		return token;
1113 	} else if (alignment > ctx->ctype.alignment)
1114 		ctx->ctype.alignment = alignment;
1115 	return token;
1116 }
1117 
apply_mod(struct position * pos,unsigned long * mods,unsigned long mod)1118 static void apply_mod(struct position *pos, unsigned long *mods, unsigned long mod)
1119 {
1120 	if (*mods & mod & ~MOD_DUP_OK)
1121 		warning(*pos, "duplicate %s", modifier_name(mod));
1122 	*mods |= mod;
1123 }
1124 
apply_qualifier(struct position * pos,struct ctype * ctx,unsigned long qual)1125 static void apply_qualifier(struct position *pos, struct ctype *ctx, unsigned long qual)
1126 {
1127 	apply_mod(pos, &ctx->modifiers, qual);
1128 }
1129 
attribute_modifier(struct token * token,struct symbol * attr,struct decl_state * ctx)1130 static struct token *attribute_modifier(struct token *token, struct symbol *attr, struct decl_state *ctx)
1131 {
1132 	apply_mod(&token->pos, &ctx->ctype.modifiers, attr->ctype.modifiers);
1133 	return token;
1134 }
1135 
attribute_function(struct token * token,struct symbol * attr,struct decl_state * ctx)1136 static struct token *attribute_function(struct token *token, struct symbol *attr, struct decl_state *ctx)
1137 {
1138 	apply_mod(&token->pos, &ctx->f_modifiers, attr->ctype.modifiers);
1139 	return token;
1140 }
1141 
attribute_bitwise(struct token * token,struct symbol * attr,struct decl_state * ctx)1142 static struct token *attribute_bitwise(struct token *token, struct symbol *attr, struct decl_state *ctx)
1143 {
1144 	if (Wbitwise)
1145 		attribute_modifier(token, attr, ctx);
1146 	return token;
1147 }
1148 
numerical_address_space(int asn)1149 static struct ident *numerical_address_space(int asn)
1150 {
1151 	char buff[32];
1152 
1153 	if (!asn)
1154 		return NULL;
1155 	sprintf(buff, "<asn:%d>", asn);
1156 	return built_in_ident(buff);
1157 }
1158 
attribute_address_space(struct token * token,struct symbol * attr,struct decl_state * ctx)1159 static struct token *attribute_address_space(struct token *token, struct symbol *attr, struct decl_state *ctx)
1160 {
1161 	struct expression *expr = NULL;
1162 	struct ident *as = NULL;
1163 	struct token *next;
1164 
1165 	token = expect(token, '(', "after address_space attribute");
1166 	switch (token_type(token)) {
1167 	case TOKEN_NUMBER:
1168 		next = primary_expression(token, &expr);
1169 		if (expr->type != EXPR_VALUE)
1170 			goto invalid;
1171 		as = numerical_address_space(expr->value);
1172 		break;
1173 	case TOKEN_IDENT:
1174 		next = token->next;
1175 		as = token->ident;
1176 		break;
1177 	default:
1178 		next = token->next;
1179 	invalid:
1180 		as = NULL;
1181 		warning(token->pos, "invalid address space name");
1182 	}
1183 
1184 	if (Waddress_space && as) {
1185 		if (ctx->ctype.as)
1186 			sparse_error(token->pos,
1187 				     "multiple address spaces given: %s & %s",
1188 				     show_as(ctx->ctype.as), show_as(as));
1189 		ctx->ctype.as = as;
1190 	}
1191 	token = expect(next, ')', "after address_space attribute");
1192 	return token;
1193 }
1194 
to_QI_mode(struct symbol * ctype)1195 static struct symbol *to_QI_mode(struct symbol *ctype)
1196 {
1197 	if (ctype->ctype.base_type != &int_type)
1198 		return NULL;
1199 	if (ctype == &char_ctype)
1200 		return ctype;
1201 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &uchar_ctype
1202 						     : &schar_ctype;
1203 }
1204 
to_HI_mode(struct symbol * ctype)1205 static struct symbol *to_HI_mode(struct symbol *ctype)
1206 {
1207 	if (ctype->ctype.base_type != &int_type)
1208 		return NULL;
1209 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &ushort_ctype
1210 						     : &sshort_ctype;
1211 }
1212 
to_SI_mode(struct symbol * ctype)1213 static struct symbol *to_SI_mode(struct symbol *ctype)
1214 {
1215 	if (ctype->ctype.base_type != &int_type)
1216 		return NULL;
1217 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &uint_ctype
1218 						     : &sint_ctype;
1219 }
1220 
to_DI_mode(struct symbol * ctype)1221 static struct symbol *to_DI_mode(struct symbol *ctype)
1222 {
1223 	if (ctype->ctype.base_type != &int_type)
1224 		return NULL;
1225 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &ullong_ctype
1226 						     : &sllong_ctype;
1227 }
1228 
to_TI_mode(struct symbol * ctype)1229 static struct symbol *to_TI_mode(struct symbol *ctype)
1230 {
1231 	if (ctype->ctype.base_type != &int_type)
1232 		return NULL;
1233 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &uint128_ctype
1234 						     : &sint128_ctype;
1235 }
1236 
to_pointer_mode(struct symbol * ctype)1237 static struct symbol *to_pointer_mode(struct symbol *ctype)
1238 {
1239 	if (ctype->ctype.base_type != &int_type)
1240 		return NULL;
1241 	return ctype->ctype.modifiers & MOD_UNSIGNED ? uintptr_ctype
1242 						     :  intptr_ctype;
1243 }
1244 
to_word_mode(struct symbol * ctype)1245 static struct symbol *to_word_mode(struct symbol *ctype)
1246 {
1247 	if (ctype->ctype.base_type != &int_type)
1248 		return NULL;
1249 	return ctype->ctype.modifiers & MOD_UNSIGNED ? &ulong_ctype
1250 						     : &slong_ctype;
1251 }
1252 
attribute_mode(struct token * token,struct symbol * attr,struct decl_state * ctx)1253 static struct token *attribute_mode(struct token *token, struct symbol *attr, struct decl_state *ctx)
1254 {
1255 	token = expect(token, '(', "after mode attribute");
1256 	if (token_type(token) == TOKEN_IDENT) {
1257 		struct symbol *mode = lookup_keyword(token->ident, NS_KEYWORD);
1258 		if (mode && mode->op->type & KW_MODE)
1259 			ctx->mode = mode->op;
1260 		else
1261 			sparse_error(token->pos, "unknown mode attribute %s", show_ident(token->ident));
1262 		token = token->next;
1263 	} else
1264 		sparse_error(token->pos, "expect attribute mode symbol\n");
1265 	token = expect(token, ')', "after mode attribute");
1266 	return token;
1267 }
1268 
attribute_context(struct token * token,struct symbol * attr,struct decl_state * ctx)1269 static struct token *attribute_context(struct token *token, struct symbol *attr, struct decl_state *ctx)
1270 {
1271 	struct context *context = alloc_context();
1272 	struct expression *args[3];
1273 	int idx = 0;
1274 
1275 	token = expect(token, '(', "after context attribute");
1276 	token = conditional_expression(token, &args[0]);
1277 	token = expect(token, ',', "after context 1st argument");
1278 	token = conditional_expression(token, &args[1]);
1279 	if (match_op(token, ',')) {
1280 		token = token->next;
1281 		token = conditional_expression(token, &args[2]);
1282 		token = expect(token, ')', "after context 3rd argument");
1283 		context->context = args[0];
1284 		idx++;
1285 	} else {
1286 		token = expect(token, ')', "after context 2nd argument");
1287 	}
1288 	context->in =  get_expression_value(args[idx++]);
1289 	context->out = get_expression_value(args[idx++]);
1290 	add_ptr_list(&ctx->ctype.contexts, context);
1291 	return token;
1292 }
1293 
attribute_designated_init(struct token * token,struct symbol * attr,struct decl_state * ctx)1294 static struct token *attribute_designated_init(struct token *token, struct symbol *attr, struct decl_state *ctx)
1295 {
1296 	if (ctx->ctype.base_type && ctx->ctype.base_type->type == SYM_STRUCT)
1297 		ctx->ctype.base_type->designated_init = 1;
1298 	else
1299 		warning(token->pos, "attribute designated_init applied to non-structure type");
1300 	return token;
1301 }
1302 
attribute_transparent_union(struct token * token,struct symbol * attr,struct decl_state * ctx)1303 static struct token *attribute_transparent_union(struct token *token, struct symbol *attr, struct decl_state *ctx)
1304 {
1305 	if (Wtransparent_union)
1306 		warning(token->pos, "attribute __transparent_union__");
1307 
1308 	if (ctx->ctype.base_type && ctx->ctype.base_type->type == SYM_UNION)
1309 		ctx->ctype.base_type->transparent_union = 1;
1310 	else
1311 		warning(token->pos, "attribute __transparent_union__ applied to non-union type");
1312 	return token;
1313 }
1314 
recover_unknown_attribute(struct token * token)1315 static struct token *recover_unknown_attribute(struct token *token)
1316 {
1317 	struct expression *expr = NULL;
1318 
1319 	if (Wunknown_attribute)
1320 		warning(token->pos, "unknown attribute '%s'", show_ident(token->ident));
1321 	token = token->next;
1322 	if (match_op(token, '('))
1323 		token = parens_expression(token, &expr, "in attribute");
1324 	return token;
1325 }
1326 
attribute_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)1327 static struct token *attribute_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
1328 {
1329 	token = expect(token, '(', "after attribute");
1330 	token = expect(token, '(', "after attribute");
1331 
1332 	while (token_type(token) == TOKEN_IDENT) {
1333 		struct symbol *attr = lookup_keyword(token->ident, NS_KEYWORD);
1334 		if (attr && attr->op->attribute)
1335 			token = attr->op->attribute(token->next, attr, ctx);
1336 		else
1337 			token = recover_unknown_attribute(token);
1338 
1339 		if (!match_op(token, ','))
1340 			break;
1341 		token = token->next;
1342 	}
1343 
1344 	token = expect(token, ')', "after attribute");
1345 	token = expect(token, ')', "after attribute");
1346 	return token;
1347 }
1348 
decl_modifiers(struct decl_state * ctx)1349 static unsigned long decl_modifiers(struct decl_state *ctx)
1350 {
1351 	unsigned long mods = ctx->ctype.modifiers & MOD_DECLARE;
1352 	ctx->ctype.modifiers &= ~MOD_DECLARE;
1353 	return ctx->storage_class | mods;
1354 }
1355 
storage_specifier(struct token * next,struct symbol * sym,struct decl_state * ctx)1356 static struct token *storage_specifier(struct token *next, struct symbol *sym, struct decl_state *ctx)
1357 {
1358 	int is_tls = ctx->ctype.modifiers & MOD_TLS;
1359 	unsigned long class = sym->ctype.modifiers;
1360 	const char *storage = modifier_name(class);
1361 
1362 	/* __thread can be used alone, or with extern or static */
1363 	if (is_tls && (class & ~(MOD_STATIC|MOD_EXTERN)))
1364 		sparse_error(next->pos, "__thread cannot be used with '%s'", storage);
1365 	else if (!ctx->storage_class)
1366 		ctx->storage_class = class;
1367 	else if (ctx->storage_class == class)
1368 		sparse_error(next->pos, "duplicate %s", storage);
1369 	else
1370 		sparse_error(next->pos, "multiple storage classes");
1371 	return next;
1372 }
1373 
thread_specifier(struct token * next,struct symbol * sym,struct decl_state * ctx)1374 static struct token *thread_specifier(struct token *next, struct symbol *sym, struct decl_state *ctx)
1375 {
1376 	/* This GCC extension can be used alone, or with extern or static */
1377 	if (!(ctx->storage_class & ~(MOD_STATIC|MOD_EXTERN))) {
1378 		apply_qualifier(&next->pos, &ctx->ctype, MOD_TLS);
1379 	} else {
1380 		sparse_error(next->pos, "__thread cannot be used with '%s'",
1381 			modifier_name(ctx->storage_class));
1382 	}
1383 
1384 	return next;
1385 }
1386 
attribute_force(struct token * token,struct symbol * attr,struct decl_state * ctx)1387 static struct token *attribute_force(struct token *token, struct symbol *attr, struct decl_state *ctx)
1388 {
1389 	ctx->forced = 1;
1390 	return token;
1391 }
1392 
alignas_specifier(struct token * token,struct symbol * sym,struct decl_state * ctx)1393 static struct token *alignas_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
1394 {
1395 	int alignment = 0;
1396 
1397 	if (!match_op(token, '(')) {
1398 		sparse_error(token->pos, "expected '(' after _Alignas");
1399 		return token;
1400 	}
1401 	if (lookup_type(token->next)) {
1402 		struct symbol *sym = NULL;
1403 		token = typename(token->next, &sym, NULL);
1404 		sym = examine_symbol_type(sym);
1405 		alignment = sym->ctype.alignment;
1406 		token = expect(token, ')', "after _Alignas(...");
1407 	} else {
1408 		struct expression *expr = NULL;
1409 		token = parens_expression(token, &expr, "after _Alignas");
1410 		if (!expr)
1411 			return token;
1412 		alignment = const_expression_value(expr);
1413 	}
1414 
1415 	if (alignment < 0) {
1416 		warning(token->pos, "non-positive alignment");
1417 		return token;
1418 	}
1419 	if (alignment & (alignment-1)) {
1420 		warning(token->pos, "non-power-of-2 alignment");
1421 		return token;
1422 	}
1423 	if (alignment > ctx->ctype.alignment)
1424 		ctx->ctype.alignment = alignment;
1425 	return token;
1426 }
1427 
generic_qualifier(struct token * next,struct symbol * sym,struct decl_state * ctx)1428 static struct token *generic_qualifier(struct token *next, struct symbol *sym, struct decl_state *ctx)
1429 {
1430 	apply_qualifier(&next->pos, &ctx->ctype, sym->ctype.modifiers);
1431 	return next;
1432 }
1433 
apply_ctype(struct position pos,struct ctype * dst,struct ctype * src)1434 static void apply_ctype(struct position pos, struct ctype *dst, struct ctype *src)
1435 {
1436 	unsigned long mod = src->modifiers;
1437 
1438 	if (mod)
1439 		apply_qualifier(&pos, dst, mod);
1440 
1441 	/* Context */
1442 	concat_ptr_list((struct ptr_list *)src->contexts,
1443 	                (struct ptr_list **)&dst->contexts);
1444 
1445 	/* Alignment */
1446 	if (src->alignment > dst->alignment)
1447 		dst->alignment = src->alignment;
1448 
1449 	/* Address space */
1450 	if (src->as)
1451 		dst->as = src->as;
1452 }
1453 
specifier_conflict(struct position pos,int what,struct ident * new)1454 static void specifier_conflict(struct position pos, int what, struct ident *new)
1455 {
1456 	const char *old;
1457 	if (what & (Set_S | Set_T))
1458 		goto Catch_all;
1459 	if (what & Set_Char)
1460 		old = "char";
1461 	else if (what & Set_Double)
1462 		old = "double";
1463 	else if (what & Set_Float)
1464 		old = "float";
1465 	else if (what & Set_Signed)
1466 		old = "signed";
1467 	else if (what & Set_Unsigned)
1468 		old = "unsigned";
1469 	else if (what & Set_Short)
1470 		old = "short";
1471 	else if (what & Set_Long)
1472 		old = "long";
1473 	else
1474 		old = "long long";
1475 	sparse_error(pos, "impossible combination of type specifiers: %s %s",
1476 			old, show_ident(new));
1477 	return;
1478 
1479 Catch_all:
1480 	sparse_error(pos, "two or more data types in declaration specifiers");
1481 }
1482 
1483 static struct symbol * const int_types[] =
1484 	{&char_ctype, &short_ctype, &int_ctype, &long_ctype, &llong_ctype, &int128_ctype};
1485 static struct symbol * const signed_types[] =
1486 	{&schar_ctype, &sshort_ctype, &sint_ctype, &slong_ctype, &sllong_ctype,
1487 	 &sint128_ctype};
1488 static struct symbol * const unsigned_types[] =
1489 	{&uchar_ctype, &ushort_ctype, &uint_ctype, &ulong_ctype, &ullong_ctype,
1490 	 &uint128_ctype};
1491 static struct symbol * const real_types[] =
1492 	{&float_ctype, &double_ctype, &ldouble_ctype};
1493 static struct symbol * const * const types[] = {
1494 	[CInt]  = int_types + 2,
1495 	[CSInt] = signed_types + 2,
1496 	[CUInt] = unsigned_types + 2,
1497 	[CReal] = real_types + 1,
1498 };
1499 
ctype_integer(int size,int want_unsigned)1500 struct symbol *ctype_integer(int size, int want_unsigned)
1501 {
1502 	return types[want_unsigned ? CUInt : CInt][size];
1503 }
1504 
handle_qualifiers(struct token * t,struct decl_state * ctx)1505 static struct token *handle_qualifiers(struct token *t, struct decl_state *ctx)
1506 {
1507 	while (token_type(t) == TOKEN_IDENT) {
1508 		struct symbol *s = lookup_keyword(t->ident, NS_TYPEDEF);
1509 		if (!s)
1510 			break;
1511 		if (!(s->op->type & (KW_ATTRIBUTE | KW_QUALIFIER)))
1512 			break;
1513 		t = t->next;
1514 		if (s->op->declarator)
1515 			t = s->op->declarator(t, s, ctx);
1516 	}
1517 	return t;
1518 }
1519 
declaration_specifiers(struct token * token,struct decl_state * ctx)1520 static struct token *declaration_specifiers(struct token *token, struct decl_state *ctx)
1521 {
1522 	int seen = 0;
1523 	int class = CInt;
1524 	int rank = 0;
1525 
1526 	while (token_type(token) == TOKEN_IDENT) {
1527 		struct symbol *s = lookup_symbol(token->ident,
1528 						 NS_TYPEDEF | NS_SYMBOL);
1529 		if (!s || !(s->namespace & NS_TYPEDEF))
1530 			break;
1531 		if (s->type != SYM_KEYWORD) {
1532 			if (seen & Set_Any)
1533 				break;
1534 			seen |= Set_S | Set_T;
1535 			ctx->ctype.base_type = s->ctype.base_type;
1536 			apply_ctype(token->pos, &ctx->ctype, &s->ctype);
1537 			token = token->next;
1538 			continue;
1539 		}
1540 		if (s->op->type & KW_SPECIFIER) {
1541 			if (seen & s->op->test) {
1542 				specifier_conflict(token->pos,
1543 						   seen & s->op->test,
1544 						   token->ident);
1545 				break;
1546 			}
1547 			seen |= s->op->set;
1548 			class += s->op->class;
1549 			if (s->op->set & Set_Int128)
1550 				rank = 3;
1551 			else if (s->op->set & Set_Char)
1552 				rank = -2;
1553 			if (s->op->set & (Set_Short|Set_Float)) {
1554 				rank = -1;
1555 			} else if (s->op->set & Set_Long && rank++) {
1556 				if (class == CReal) {
1557 					specifier_conflict(token->pos,
1558 							   Set_Vlong,
1559 							   &double_ident);
1560 					break;
1561 				}
1562 				seen |= Set_Vlong;
1563 			}
1564 		}
1565 		token = token->next;
1566 		if (s->op->declarator)	// Note: this eats attributes
1567 			token = s->op->declarator(token, s, ctx);
1568 		if (s->op->type & KW_EXACT) {
1569 			ctx->ctype.base_type = s->ctype.base_type;
1570 			ctx->ctype.modifiers |= s->ctype.modifiers;
1571 		}
1572 	}
1573 
1574 	if (!(seen & Set_S)) {	/* not set explicitly? */
1575 		struct symbol *base = &incomplete_ctype;
1576 		if (seen & Set_Any)
1577 			base = types[class][rank];
1578 		ctx->ctype.base_type = base;
1579 	}
1580 
1581 	if (ctx->ctype.modifiers & MOD_BITWISE) {
1582 		struct symbol *type;
1583 		ctx->ctype.modifiers &= ~MOD_BITWISE;
1584 		if (!is_int_type(ctx->ctype.base_type)) {
1585 			sparse_error(token->pos, "invalid modifier");
1586 			return token;
1587 		}
1588 		type = alloc_symbol(token->pos, SYM_BASETYPE);
1589 		*type = *ctx->ctype.base_type;
1590 		type->ctype.modifiers &= ~MOD_SPECIFIER;
1591 		type->ctype.base_type = ctx->ctype.base_type;
1592 		type->type = SYM_RESTRICT;
1593 		ctx->ctype.base_type = type;
1594 		create_fouled(type);
1595 	}
1596 	return token;
1597 }
1598 
abstract_array_declarator(struct token * token,struct symbol * sym)1599 static struct token *abstract_array_declarator(struct token *token, struct symbol *sym)
1600 {
1601 	struct expression *expr = NULL;
1602 	int has_static = 0;
1603 
1604 	while (token_type(token) == TOKEN_IDENT) {
1605 		struct symbol *sym = lookup_keyword(token->ident, NS_TYPEDEF);
1606 		if (!sym || !(sym->op->type & (KW_STATIC|KW_QUALIFIER)))
1607 			break;
1608 		if (has_static && (sym->op->type & KW_STATIC))
1609 			sparse_error(token->pos, "duplicate array static declarator");
1610 		has_static |= (sym->op->type & KW_STATIC);
1611 		token = token->next;
1612 	}
1613 	if (match_op(token, '*') && match_op(token->next, ']')) {
1614 		// FIXME: '[*]' is treated like '[]'
1615 		token = token->next;
1616 	} else {
1617 		token = assignment_expression(token, &expr);
1618 	}
1619 	sym->array_size = expr;
1620 	return token;
1621 }
1622 
1623 static struct token *parameter_type_list(struct token *, struct symbol *);
1624 static struct token *identifier_list(struct token *, struct symbol *);
1625 static struct token *declarator(struct token *token, struct decl_state *ctx);
1626 
handle_asm_name(struct token * token,struct decl_state * ctx)1627 static struct token *handle_asm_name(struct token *token, struct decl_state *ctx)
1628 {
1629 	struct expression *expr;
1630 	struct symbol *keyword;
1631 
1632 	if (token_type(token) != TOKEN_IDENT)
1633 		return token;
1634 	keyword = lookup_keyword(token->ident, NS_KEYWORD);
1635 	if (!keyword)
1636 		return token;
1637 	if (!(keyword->op->type & KW_ASM))
1638 		return token;
1639 
1640 	token = token->next;
1641 	token = expect(token, '(', "after asm");
1642 	token = string_expression(token, &expr, "asm name");
1643 	token = expect(token, ')', "after asm");
1644 	return token;
1645 }
1646 
1647 ///
1648 // test if @token is '__attribute__' (or one of its variant)
match_attribute(struct token * token)1649 static bool match_attribute(struct token *token)
1650 {
1651 	struct symbol *sym;
1652 
1653 	if (token_type(token) != TOKEN_IDENT)
1654 		return false;
1655 	sym = lookup_keyword(token->ident, NS_TYPEDEF);
1656 	if (!sym || !sym->op)
1657 		return false;
1658 	return sym->op->type & KW_ATTRIBUTE;
1659 }
1660 
skip_attribute(struct token * token)1661 static struct token *skip_attribute(struct token *token)
1662 {
1663 	token = token->next;
1664 	if (match_op(token, '(')) {
1665 		int depth = 1;
1666 		token = token->next;
1667 		while (depth && !eof_token(token)) {
1668 			if (token_type(token) == TOKEN_SPECIAL) {
1669 				if (token->special == '(')
1670 					depth++;
1671 				else if (token->special == ')')
1672 					depth--;
1673 			}
1674 			token = token->next;
1675 		}
1676 	}
1677 	return token;
1678 }
1679 
skip_attributes(struct token * token)1680 static struct token *skip_attributes(struct token *token)
1681 {
1682 	while (match_attribute(token)) {
1683 		token = expect(token->next, '(', "after attribute");
1684 		token = expect(token, '(', "after attribute");
1685 		while (token_type(token) == TOKEN_IDENT) {
1686 			token = skip_attribute(token);
1687 			if (!match_op(token, ','))
1688 				break;
1689 			token = token->next;
1690 		}
1691 		token = expect(token, ')', "after attribute");
1692 		token = expect(token, ')', "after attribute");
1693 	}
1694 	return token;
1695 }
1696 
handle_attributes(struct token * token,struct decl_state * ctx)1697 static struct token *handle_attributes(struct token *token, struct decl_state *ctx)
1698 {
1699 	while (match_attribute(token))
1700 		token = attribute_specifier(token->next, NULL, ctx);
1701 	return token;
1702 }
1703 
is_nested(struct token * token,struct token ** p,int prefer_abstract)1704 static int is_nested(struct token *token, struct token **p,
1705 		    int prefer_abstract)
1706 {
1707 	/*
1708 	 * This can be either a parameter list or a grouping.
1709 	 * For the direct (non-abstract) case, we know if must be
1710 	 * a parameter list if we already saw the identifier.
1711 	 * For the abstract case, we know if must be a parameter
1712 	 * list if it is empty or starts with a type.
1713 	 */
1714 	struct token *next = token->next;
1715 
1716 	*p = next = skip_attributes(next);
1717 
1718 	if (token_type(next) == TOKEN_IDENT) {
1719 		if (lookup_type(next))
1720 			return !prefer_abstract;
1721 		return 1;
1722 	}
1723 
1724 	if (match_op(next, ')') || match_op(next, SPECIAL_ELLIPSIS))
1725 		return 0;
1726 
1727 	return 1;
1728 }
1729 
1730 enum kind {
1731 	Empty, K_R, Proto, Bad_Func,
1732 };
1733 
which_func(struct token * token,struct ident ** n,int prefer_abstract)1734 static enum kind which_func(struct token *token,
1735 			    struct ident **n,
1736 			    int prefer_abstract)
1737 {
1738 	struct token *next = token->next;
1739 
1740 	if (token_type(next) == TOKEN_IDENT) {
1741 		if (lookup_type(next))
1742 			return Proto;
1743 		/* identifier list not in definition; complain */
1744 		if (prefer_abstract)
1745 			warning(token->pos,
1746 				"identifier list not in definition");
1747 		return K_R;
1748 	}
1749 
1750 	if (token_type(next) != TOKEN_SPECIAL)
1751 		return Bad_Func;
1752 
1753 	if (next->special == ')') {
1754 		/* don't complain about those */
1755 		if (!n || match_op(next->next, ';') || match_op(next->next, ','))
1756 			return Empty;
1757 		if (Wstrict_prototypes)
1758 			warning(next->pos,
1759 				"non-ANSI function declaration of function '%s'",
1760 				show_ident(*n));
1761 		return Empty;
1762 	}
1763 
1764 	if (next->special == SPECIAL_ELLIPSIS) {
1765 		warning(next->pos,
1766 			"variadic functions must have one named argument");
1767 		return Proto;
1768 	}
1769 
1770 	return Bad_Func;
1771 }
1772 
direct_declarator(struct token * token,struct decl_state * ctx)1773 static struct token *direct_declarator(struct token *token, struct decl_state *ctx)
1774 {
1775 	struct ctype *ctype = &ctx->ctype;
1776 	struct token *next;
1777 	struct ident **p = ctx->ident;
1778 
1779 	if (ctx->ident && token_type(token) == TOKEN_IDENT) {
1780 		*ctx->ident = token->ident;
1781 		token = token->next;
1782 	} else if (match_op(token, '(') &&
1783 	    is_nested(token, &next, ctx->prefer_abstract)) {
1784 		struct symbol *base_type = ctype->base_type;
1785 		if (token->next != next)
1786 			next = handle_attributes(token->next, ctx);
1787 		token = declarator(next, ctx);
1788 		token = expect(token, ')', "in nested declarator");
1789 		while (ctype->base_type != base_type)
1790 			ctype = &ctype->base_type->ctype;
1791 		p = NULL;
1792 	}
1793 
1794 	if (match_op(token, '(')) {
1795 		enum kind kind = which_func(token, p, ctx->prefer_abstract);
1796 		struct symbol *fn;
1797 		fn = alloc_indirect_symbol(token->pos, ctype, SYM_FN);
1798 		ctype->modifiers |= ctx->f_modifiers;
1799 		token = token->next;
1800 		if (kind == K_R)
1801 			token = identifier_list(token, fn);
1802 		else if (kind == Proto)
1803 			token = parameter_type_list(token, fn);
1804 		token = expect(token, ')', "in function declarator");
1805 		fn->endpos = token->pos;
1806 		return token;
1807 	}
1808 
1809 	while (match_op(token, '[')) {
1810 		struct symbol *array;
1811 		array = alloc_indirect_symbol(token->pos, ctype, SYM_ARRAY);
1812 		token = abstract_array_declarator(token->next, array);
1813 		token = expect(token, ']', "in abstract_array_declarator");
1814 		array->endpos = token->pos;
1815 		ctype = &array->ctype;
1816 	}
1817 	return token;
1818 }
1819 
pointer(struct token * token,struct decl_state * ctx)1820 static struct token *pointer(struct token *token, struct decl_state *ctx)
1821 {
1822 	while (match_op(token,'*')) {
1823 		struct symbol *ptr = alloc_symbol(token->pos, SYM_PTR);
1824 		ptr->ctype.modifiers = ctx->ctype.modifiers;
1825 		ptr->ctype.base_type = ctx->ctype.base_type;
1826 		ptr->ctype.as = ctx->ctype.as;
1827 		ptr->ctype.contexts = ctx->ctype.contexts;
1828 		ctx->ctype.modifiers = 0;
1829 		ctx->ctype.base_type = ptr;
1830 		ctx->ctype.as = NULL;
1831 		ctx->ctype.contexts = NULL;
1832 		ctx->ctype.alignment = 0;
1833 
1834 		token = handle_qualifiers(token->next, ctx);
1835 		ctx->ctype.base_type->endpos = token->pos;
1836 	}
1837 	return token;
1838 }
1839 
declarator(struct token * token,struct decl_state * ctx)1840 static struct token *declarator(struct token *token, struct decl_state *ctx)
1841 {
1842 	token = pointer(token, ctx);
1843 	return direct_declarator(token, ctx);
1844 }
1845 
handle_bitfield(struct token * token,struct decl_state * ctx)1846 static struct token *handle_bitfield(struct token *token, struct decl_state *ctx)
1847 {
1848 	struct ctype *ctype = &ctx->ctype;
1849 	struct expression *expr;
1850 	struct symbol *bitfield;
1851 	long long width;
1852 
1853 	if (ctype->base_type != &int_type && !is_int_type(ctype->base_type)) {
1854 		sparse_error(token->pos, "invalid bitfield specifier for type %s.",
1855 			show_typename(ctype->base_type));
1856 		// Parse this to recover gracefully.
1857 		return conditional_expression(token->next, &expr);
1858 	}
1859 
1860 	bitfield = alloc_indirect_symbol(token->pos, ctype, SYM_BITFIELD);
1861 	token = conditional_expression(token->next, &expr);
1862 	width = const_expression_value(expr);
1863 	bitfield->bit_size = width;
1864 
1865 	if (width < 0 || width > INT_MAX || (*ctx->ident && width == 0)) {
1866 		sparse_error(token->pos, "bitfield '%s' has invalid width (%lld)",
1867 			show_ident(*ctx->ident), width);
1868 		width = -1;
1869 	} else if (*ctx->ident) {
1870 		struct symbol *base_type = bitfield->ctype.base_type;
1871 		struct symbol *bitfield_type = base_type == &int_type ? bitfield : base_type;
1872 		int is_signed = !(bitfield_type->ctype.modifiers & MOD_UNSIGNED);
1873 		if (Wone_bit_signed_bitfield && width == 1 && is_signed) {
1874 			// Valid values are either {-1;0} or {0}, depending on integer
1875 			// representation.  The latter makes for very efficient code...
1876 			sparse_error(token->pos, "dubious one-bit signed bitfield");
1877 		}
1878 		if (Wdefault_bitfield_sign &&
1879 		    bitfield_type->type != SYM_ENUM &&
1880 		    !(bitfield_type->ctype.modifiers & MOD_EXPLICITLY_SIGNED) &&
1881 		    is_signed) {
1882 			// The sign of bitfields is unspecified by default.
1883 			warning(token->pos, "dubious bitfield without explicit `signed' or `unsigned'");
1884 		}
1885 	}
1886 	bitfield->bit_size = width;
1887 	bitfield->endpos = token->pos;
1888 	bitfield->ident = *ctx->ident;
1889 	return token;
1890 }
1891 
declaration_list(struct token * token,struct symbol_list ** list)1892 static struct token *declaration_list(struct token *token, struct symbol_list **list)
1893 {
1894 	struct decl_state ctx = {.prefer_abstract = 0};
1895 	struct ctype saved;
1896 	unsigned long mod;
1897 
1898 	token = declaration_specifiers(token, &ctx);
1899 	mod = decl_modifiers(&ctx);
1900 	saved = ctx.ctype;
1901 	for (;;) {
1902 		struct symbol *decl = alloc_symbol(token->pos, SYM_NODE);
1903 		ctx.ident = &decl->ident;
1904 
1905 		token = declarator(token, &ctx);
1906 		if (match_op(token, ':'))
1907 			token = handle_bitfield(token, &ctx);
1908 
1909 		token = handle_attributes(token, &ctx);
1910 		apply_modifiers(token->pos, &ctx);
1911 
1912 		decl->ctype = ctx.ctype;
1913 		decl->ctype.modifiers |= mod;
1914 		decl->endpos = token->pos;
1915 		add_symbol(list, decl);
1916 		if (!match_op(token, ','))
1917 			break;
1918 		token = token->next;
1919 		ctx.ctype = saved;
1920 	}
1921 	return token;
1922 }
1923 
struct_declaration_list(struct token * token,struct symbol_list ** list)1924 static struct token *struct_declaration_list(struct token *token, struct symbol_list **list)
1925 {
1926 	while (!match_op(token, '}')) {
1927 		if (match_ident(token, &_Static_assert_ident)) {
1928 			token = parse_static_assert(token, NULL);
1929 			continue;
1930 		}
1931 		if (!match_op(token, ';'))
1932 			token = declaration_list(token, list);
1933 		if (!match_op(token, ';')) {
1934 			sparse_error(token->pos, "expected ; at end of declaration");
1935 			break;
1936 		}
1937 		token = token->next;
1938 	}
1939 	return token;
1940 }
1941 
parameter_declaration(struct token * token,struct symbol * sym)1942 static struct token *parameter_declaration(struct token *token, struct symbol *sym)
1943 {
1944 	struct decl_state ctx = {.prefer_abstract = 1};
1945 
1946 	token = declaration_specifiers(token, &ctx);
1947 	ctx.ident = &sym->ident;
1948 	token = declarator(token, &ctx);
1949 	token = handle_attributes(token, &ctx);
1950 	apply_modifiers(token->pos, &ctx);
1951 	sym->ctype = ctx.ctype;
1952 	sym->ctype.modifiers |= decl_modifiers(&ctx);
1953 	sym->endpos = token->pos;
1954 	sym->forced_arg = ctx.forced;
1955 	return token;
1956 }
1957 
typename(struct token * token,struct symbol ** p,int * forced)1958 struct token *typename(struct token *token, struct symbol **p, int *forced)
1959 {
1960 	struct decl_state ctx = {.prefer_abstract = 1};
1961 	unsigned long class;
1962 	struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
1963 	*p = sym;
1964 	token = declaration_specifiers(token, &ctx);
1965 	token = declarator(token, &ctx);
1966 	apply_modifiers(token->pos, &ctx);
1967 	sym->ctype = ctx.ctype;
1968 	sym->endpos = token->pos;
1969 	class = ctx.storage_class;
1970 	if (forced)
1971 		*forced = ctx.forced;
1972 	if (class)
1973 		warning(sym->pos, "storage class in typename (%s%s)",
1974 			modifier_string(class), show_typename(sym));
1975 	return token;
1976 }
1977 
expression_statement(struct token * token,struct expression ** tree)1978 static struct token *expression_statement(struct token *token, struct expression **tree)
1979 {
1980 	token = parse_expression(token, tree);
1981 	return expect(token, ';', "at end of statement");
1982 }
1983 
parse_asm_operands(struct token * token,struct statement * stmt,struct asm_operand_list ** inout)1984 static struct token *parse_asm_operands(struct token *token, struct statement *stmt,
1985 	struct asm_operand_list **inout)
1986 {
1987 	/* Allow empty operands */
1988 	if (match_op(token->next, ':') || match_op(token->next, ')'))
1989 		return token->next;
1990 	do {
1991 		struct asm_operand *op = __alloc_asm_operand(0);
1992 		if (match_op(token->next, '[') &&
1993 		    token_type(token->next->next) == TOKEN_IDENT &&
1994 		    match_op(token->next->next->next, ']')) {
1995 			op->name = token->next->next->ident;
1996 			token = token->next->next->next;
1997 		}
1998 		token = token->next;
1999 		token = string_expression(token, &op->constraint, "asm constraint");
2000 		token = parens_expression(token, &op->expr, "in asm parameter");
2001 		add_ptr_list(inout, op);
2002 	} while (match_op(token, ','));
2003 	return token;
2004 }
2005 
parse_asm_clobbers(struct token * token,struct statement * stmt,struct expression_list ** clobbers)2006 static struct token *parse_asm_clobbers(struct token *token, struct statement *stmt,
2007 	struct expression_list **clobbers)
2008 {
2009 	struct expression *expr;
2010 
2011 	do {
2012 		token = primary_expression(token->next, &expr);
2013 		if (expr)
2014 			add_expression(clobbers, expr);
2015 	} while (match_op(token, ','));
2016 	return token;
2017 }
2018 
parse_asm_labels(struct token * token,struct statement * stmt,struct symbol_list ** labels)2019 static struct token *parse_asm_labels(struct token *token, struct statement *stmt,
2020 		        struct symbol_list **labels)
2021 {
2022 	struct symbol *label;
2023 
2024 	do {
2025 		token = token->next; /* skip ':' and ',' */
2026 		if (token_type(token) != TOKEN_IDENT)
2027 			return token;
2028 		label = label_symbol(token, 1);
2029 		add_symbol(labels, label);
2030 		token = token->next;
2031 	} while (match_op(token, ','));
2032 	return token;
2033 }
2034 
parse_asm_statement(struct token * token,struct statement * stmt)2035 static struct token *parse_asm_statement(struct token *token, struct statement *stmt)
2036 {
2037 	unsigned long mods = 0;
2038 
2039 	token = token->next;
2040 	stmt->type = STMT_ASM;
2041 	while (token_type(token) == TOKEN_IDENT) {
2042 		struct symbol *s = lookup_keyword(token->ident, NS_TYPEDEF);
2043 		if (s && s->op->asm_modifier)
2044 			s->op->asm_modifier(token, &mods, s->ctype.modifiers);
2045 		else if (token->ident == &goto_ident)
2046 			asm_modifier(token, &mods, MOD_ASM_GOTO);
2047 		token = token->next;
2048 	}
2049 	token = expect(token, '(', "after asm");
2050 	token = string_expression(token, &stmt->asm_string, "inline asm");
2051 	if (match_op(token, ':'))
2052 		token = parse_asm_operands(token, stmt, &stmt->asm_outputs);
2053 	if (match_op(token, ':'))
2054 		token = parse_asm_operands(token, stmt, &stmt->asm_inputs);
2055 	if (match_op(token, ':'))
2056 		token = parse_asm_clobbers(token, stmt, &stmt->asm_clobbers);
2057 	if (match_op(token, ':') && (mods & MOD_ASM_GOTO))
2058 		token = parse_asm_labels(token, stmt, &stmt->asm_labels);
2059 	token = expect(token, ')', "after asm");
2060 	return expect(token, ';', "at end of asm-statement");
2061 }
2062 
parse_static_assert(struct token * token,struct symbol_list ** unused)2063 static struct token *parse_static_assert(struct token *token, struct symbol_list **unused)
2064 {
2065 	struct expression *cond = NULL, *message = NULL;
2066 
2067 	token = expect(token->next, '(', "after _Static_assert");
2068 	token = constant_expression(token, &cond);
2069 	if (!cond)
2070 		sparse_error(token->pos, "Expected constant expression");
2071 	if (match_op(token, ',')) {
2072 		token = token->next;
2073 		token = string_expression(token, &message, "_Static_assert()");
2074 		if (!message)
2075 			cond = NULL;
2076 	}
2077 	token = expect(token, ')', "after diagnostic message in _Static_assert");
2078 	token = expect(token, ';', "after _Static_assert()");
2079 
2080 	if (cond && !const_expression_value(cond) && cond->type == EXPR_VALUE) {
2081 		const char *sep = "", *msg = "";
2082 
2083 		if (message) {
2084 			sep = ": ";
2085 			msg = show_string(message->string);
2086 		}
2087 		sparse_error(cond->pos, "static assertion failed%s%s", sep, msg);
2088 	}
2089 
2090 	return token;
2091 }
2092 
2093 /* Make a statement out of an expression */
make_statement(struct expression * expr)2094 static struct statement *make_statement(struct expression *expr)
2095 {
2096 	struct statement *stmt;
2097 
2098 	if (!expr)
2099 		return NULL;
2100 	stmt = alloc_statement(expr->pos, STMT_EXPRESSION);
2101 	stmt->expression = expr;
2102 	return stmt;
2103 }
2104 
2105 /*
2106  * All iterators have two symbols associated with them:
2107  * the "continue" and "break" symbols, which are targets
2108  * for continue and break statements respectively.
2109  *
2110  * They are in a special name-space, but they follow
2111  * all the normal visibility rules, so nested iterators
2112  * automatically work right.
2113  */
start_iterator(struct statement * stmt)2114 static void start_iterator(struct statement *stmt)
2115 {
2116 	struct symbol *cont, *brk;
2117 
2118 	start_block_scope();
2119 	cont = alloc_symbol(stmt->pos, SYM_NODE);
2120 	bind_symbol(cont, &continue_ident, NS_ITERATOR);
2121 	brk = alloc_symbol(stmt->pos, SYM_NODE);
2122 	bind_symbol(brk, &break_ident, NS_ITERATOR);
2123 
2124 	stmt->type = STMT_ITERATOR;
2125 	stmt->iterator_break = brk;
2126 	stmt->iterator_continue = cont;
2127 	fn_local_symbol(brk);
2128 	fn_local_symbol(cont);
2129 }
2130 
end_iterator(struct statement * stmt)2131 static void end_iterator(struct statement *stmt)
2132 {
2133 	end_block_scope();
2134 }
2135 
start_function(struct symbol * sym)2136 static struct statement *start_function(struct symbol *sym)
2137 {
2138 	struct symbol *ret;
2139 	struct statement *stmt = alloc_statement(sym->pos, STMT_COMPOUND);
2140 
2141 	start_function_scope();
2142 	ret = alloc_symbol(sym->pos, SYM_NODE);
2143 	ret->ctype = sym->ctype.base_type->ctype;
2144 	ret->ctype.modifiers &= ~(MOD_STORAGE | MOD_QUALIFIER | MOD_TLS | MOD_ACCESS | MOD_NOCAST | MOD_NODEREF);
2145 	ret->ctype.modifiers |= (MOD_AUTO | MOD_REGISTER);
2146 	bind_symbol(ret, &return_ident, NS_ITERATOR);
2147 	stmt->ret = ret;
2148 	fn_local_symbol(ret);
2149 
2150 	// Currently parsed symbol for __func__/__FUNCTION__/__PRETTY_FUNCTION__
2151 	current_fn = sym;
2152 
2153 	return stmt;
2154 }
2155 
end_function(struct symbol * sym)2156 static void end_function(struct symbol *sym)
2157 {
2158 	current_fn = NULL;
2159 	end_function_scope();
2160 }
2161 
2162 /*
2163  * A "switch()" statement, like an iterator, has a
2164  * the "break" symbol associated with it. It works
2165  * exactly like the iterator break - it's the target
2166  * for any break-statements in scope, and means that
2167  * "break" handling doesn't even need to know whether
2168  * it's breaking out of an iterator or a switch.
2169  *
2170  * In addition, the "case" symbol is a marker for the
2171  * case/default statements to find the switch statement
2172  * that they are associated with.
2173  */
start_switch(struct statement * stmt)2174 static void start_switch(struct statement *stmt)
2175 {
2176 	struct symbol *brk, *switch_case;
2177 
2178 	start_block_scope();
2179 	brk = alloc_symbol(stmt->pos, SYM_NODE);
2180 	bind_symbol(brk, &break_ident, NS_ITERATOR);
2181 
2182 	switch_case = alloc_symbol(stmt->pos, SYM_NODE);
2183 	bind_symbol(switch_case, &case_ident, NS_ITERATOR);
2184 	switch_case->stmt = stmt;
2185 
2186 	stmt->type = STMT_SWITCH;
2187 	stmt->switch_break = brk;
2188 	stmt->switch_case = switch_case;
2189 
2190 	fn_local_symbol(brk);
2191 	fn_local_symbol(switch_case);
2192 }
2193 
end_switch(struct statement * stmt)2194 static void end_switch(struct statement *stmt)
2195 {
2196 	if (!stmt->switch_case->symbol_list)
2197 		warning(stmt->pos, "switch with no cases");
2198 	end_block_scope();
2199 }
2200 
add_case_statement(struct statement * stmt)2201 static void add_case_statement(struct statement *stmt)
2202 {
2203 	struct symbol *target = lookup_symbol(&case_ident, NS_ITERATOR);
2204 	struct symbol *sym;
2205 
2206 	if (!target) {
2207 		sparse_error(stmt->pos, "not in switch scope");
2208 		stmt->type = STMT_NONE;
2209 		return;
2210 	}
2211 	sym = alloc_symbol(stmt->pos, SYM_NODE);
2212 	add_symbol(&target->symbol_list, sym);
2213 	sym->stmt = stmt;
2214 	stmt->case_label = sym;
2215 	fn_local_symbol(sym);
2216 }
2217 
parse_return_statement(struct token * token,struct statement * stmt)2218 static struct token *parse_return_statement(struct token *token, struct statement *stmt)
2219 {
2220 	struct symbol *target = lookup_symbol(&return_ident, NS_ITERATOR);
2221 
2222 	if (!target)
2223 		error_die(token->pos, "internal error: return without a function target");
2224 	stmt->type = STMT_RETURN;
2225 	stmt->ret_target = target;
2226 	return expression_statement(token->next, &stmt->ret_value);
2227 }
2228 
validate_for_loop_decl(struct symbol * sym)2229 static void validate_for_loop_decl(struct symbol *sym)
2230 {
2231 	unsigned long storage = sym->ctype.modifiers & MOD_STORAGE;
2232 
2233 	if (storage & ~(MOD_AUTO | MOD_REGISTER)) {
2234 		const char *name = show_ident(sym->ident);
2235 		sparse_error(sym->pos, "non-local var '%s' in for-loop initializer", name);
2236 		sym->ctype.modifiers &= ~MOD_STORAGE;
2237 	}
2238 }
2239 
parse_for_statement(struct token * token,struct statement * stmt)2240 static struct token *parse_for_statement(struct token *token, struct statement *stmt)
2241 {
2242 	struct symbol_list *syms;
2243 	struct expression *e1, *e2, *e3;
2244 	struct statement *iterator;
2245 
2246 	start_iterator(stmt);
2247 	token = expect(token->next, '(', "after 'for'");
2248 
2249 	syms = NULL;
2250 	e1 = NULL;
2251 	/* C99 variable declaration? */
2252 	if (lookup_type(token)) {
2253 		token = external_declaration(token, &syms, validate_for_loop_decl);
2254 	} else {
2255 		token = parse_expression(token, &e1);
2256 		token = expect(token, ';', "in 'for'");
2257 	}
2258 	token = parse_expression(token, &e2);
2259 	token = expect(token, ';', "in 'for'");
2260 	token = parse_expression(token, &e3);
2261 	token = expect(token, ')', "in 'for'");
2262 	token = statement(token, &iterator);
2263 
2264 	stmt->iterator_syms = syms;
2265 	stmt->iterator_pre_statement = make_statement(e1);
2266 	stmt->iterator_pre_condition = e2;
2267 	stmt->iterator_post_statement = make_statement(e3);
2268 	stmt->iterator_post_condition = NULL;
2269 	stmt->iterator_statement = iterator;
2270 	end_iterator(stmt);
2271 
2272 	return token;
2273 }
2274 
parse_while_statement(struct token * token,struct statement * stmt)2275 static struct token *parse_while_statement(struct token *token, struct statement *stmt)
2276 {
2277 	struct expression *expr;
2278 	struct statement *iterator;
2279 
2280 	start_iterator(stmt);
2281 	token = parens_expression(token->next, &expr, "after 'while'");
2282 	token = statement(token, &iterator);
2283 
2284 	stmt->iterator_pre_condition = expr;
2285 	stmt->iterator_post_condition = NULL;
2286 	stmt->iterator_statement = iterator;
2287 	end_iterator(stmt);
2288 
2289 	return token;
2290 }
2291 
parse_do_statement(struct token * token,struct statement * stmt)2292 static struct token *parse_do_statement(struct token *token, struct statement *stmt)
2293 {
2294 	struct expression *expr;
2295 	struct statement *iterator;
2296 
2297 	start_iterator(stmt);
2298 	token = statement(token->next, &iterator);
2299 	if (token_type(token) == TOKEN_IDENT && token->ident == &while_ident)
2300 		token = token->next;
2301 	else
2302 		sparse_error(token->pos, "expected 'while' after 'do'");
2303 	token = parens_expression(token, &expr, "after 'do-while'");
2304 
2305 	stmt->iterator_post_condition = expr;
2306 	stmt->iterator_statement = iterator;
2307 	end_iterator(stmt);
2308 
2309 	if (iterator && iterator->type != STMT_COMPOUND && Wdo_while)
2310 		warning(iterator->pos, "do-while statement is not a compound statement");
2311 
2312 	return expect(token, ';', "after statement");
2313 }
2314 
parse_if_statement(struct token * token,struct statement * stmt)2315 static struct token *parse_if_statement(struct token *token, struct statement *stmt)
2316 {
2317 	stmt->type = STMT_IF;
2318 	token = parens_expression(token->next, &stmt->if_conditional, "after if");
2319 	token = statement(token, &stmt->if_true);
2320 	if (token_type(token) != TOKEN_IDENT)
2321 		return token;
2322 	if (token->ident != &else_ident)
2323 		return token;
2324 	return statement(token->next, &stmt->if_false);
2325 }
2326 
case_statement(struct token * token,struct statement * stmt)2327 static inline struct token *case_statement(struct token *token, struct statement *stmt)
2328 {
2329 	stmt->type = STMT_CASE;
2330 	token = expect(token, ':', "after default/case");
2331 	add_case_statement(stmt);
2332 	return statement(token, &stmt->case_statement);
2333 }
2334 
parse_case_statement(struct token * token,struct statement * stmt)2335 static struct token *parse_case_statement(struct token *token, struct statement *stmt)
2336 {
2337 	token = parse_expression(token->next, &stmt->case_expression);
2338 	if (match_op(token, SPECIAL_ELLIPSIS))
2339 		token = parse_expression(token->next, &stmt->case_to);
2340 	return case_statement(token, stmt);
2341 }
2342 
parse_default_statement(struct token * token,struct statement * stmt)2343 static struct token *parse_default_statement(struct token *token, struct statement *stmt)
2344 {
2345 	return case_statement(token->next, stmt);
2346 }
2347 
parse_loop_iterator(struct token * token,struct statement * stmt)2348 static struct token *parse_loop_iterator(struct token *token, struct statement *stmt)
2349 {
2350 	struct symbol *target = lookup_symbol(token->ident, NS_ITERATOR);
2351 	stmt->type = STMT_GOTO;
2352 	stmt->goto_label = target;
2353 	if (!target)
2354 		sparse_error(stmt->pos, "break/continue not in iterator scope");
2355 	return expect(token->next, ';', "at end of statement");
2356 }
2357 
parse_switch_statement(struct token * token,struct statement * stmt)2358 static struct token *parse_switch_statement(struct token *token, struct statement *stmt)
2359 {
2360 	stmt->type = STMT_SWITCH;
2361 	start_switch(stmt);
2362 	token = parens_expression(token->next, &stmt->switch_expression, "after 'switch'");
2363 	token = statement(token, &stmt->switch_statement);
2364 	end_switch(stmt);
2365 	return token;
2366 }
2367 
warn_label_usage(struct position def,struct position use,struct ident * ident)2368 static void warn_label_usage(struct position def, struct position use, struct ident *ident)
2369 {
2370 	const char *id = show_ident(ident);
2371 	sparse_error(use, "label '%s' used outside statement expression", id);
2372 	info(def, "   label '%s' defined here", id);
2373 	current_fn->bogus_linear = 1;
2374 }
2375 
check_label_usage(struct symbol * label,struct position use_pos)2376 void check_label_usage(struct symbol *label, struct position use_pos)
2377 {
2378 	struct statement *def = label->stmt;
2379 
2380 	if (def) {
2381 		if (!is_in_scope(def->label_scope, label_scope))
2382 			warn_label_usage(def->pos, use_pos, label->ident);
2383 	} else if (!label->label_scope) {
2384 		label->label_scope = label_scope;
2385 		label->label_pos = use_pos;
2386 	}
2387 }
2388 
parse_goto_statement(struct token * token,struct statement * stmt)2389 static struct token *parse_goto_statement(struct token *token, struct statement *stmt)
2390 {
2391 	stmt->type = STMT_GOTO;
2392 	token = token->next;
2393 	if (match_op(token, '*')) {
2394 		token = parse_expression(token->next, &stmt->goto_expression);
2395 		add_statement(&function_computed_goto_list, stmt);
2396 	} else if (token_type(token) == TOKEN_IDENT) {
2397 		struct symbol *label = label_symbol(token, 1);
2398 		stmt->goto_label = label;
2399 		check_label_usage(label, stmt->pos);
2400 		token = token->next;
2401 	} else {
2402 		sparse_error(token->pos, "Expected identifier or goto expression");
2403 	}
2404 	return expect(token, ';', "at end of statement");
2405 }
2406 
parse_context_statement(struct token * token,struct statement * stmt)2407 static struct token *parse_context_statement(struct token *token, struct statement *stmt)
2408 {
2409 	stmt->type = STMT_CONTEXT;
2410 	token = token->next;
2411 	token = expect(token, '(', "after __context__ statement");
2412 	token = assignment_expression(token, &stmt->expression);
2413 	if (!stmt->expression)
2414 		unexpected(token, "expression expected after '('");
2415 	if (match_op(token, ',')) {
2416 		token = token->next;
2417 		stmt->context = stmt->expression;
2418 		token = assignment_expression(token, &stmt->expression);
2419 		if (!stmt->expression)
2420 			unexpected(token, "expression expected after ','");
2421 	}
2422 	token = expect(token, ')', "at end of __context__ statement");
2423 	return expect(token, ';', "at end of statement");
2424 }
2425 
parse_range_statement(struct token * token,struct statement * stmt)2426 static struct token *parse_range_statement(struct token *token, struct statement *stmt)
2427 {
2428 	stmt->type = STMT_RANGE;
2429 	token = token->next;
2430 	token = expect(token, '(', "after __range__ statement");
2431 	token = assignment_expression(token, &stmt->range_expression);
2432 	token = expect(token, ',', "after range expression");
2433 	token = assignment_expression(token, &stmt->range_low);
2434 	token = expect(token, ',', "after low range");
2435 	token = assignment_expression(token, &stmt->range_high);
2436 	token = expect(token, ')', "after range statement");
2437 	return expect(token, ';', "after range statement");
2438 }
2439 
handle_label_attributes(struct token * token,struct symbol * label)2440 static struct token *handle_label_attributes(struct token *token, struct symbol *label)
2441 {
2442 	struct decl_state ctx = { };
2443 
2444 	token = handle_attributes(token, &ctx);
2445 	label->label_modifiers = ctx.ctype.modifiers;
2446 	return token;
2447 }
2448 
statement(struct token * token,struct statement ** tree)2449 static struct token *statement(struct token *token, struct statement **tree)
2450 {
2451 	struct statement *stmt = alloc_statement(token->pos, STMT_NONE);
2452 
2453 	*tree = stmt;
2454 	if (token_type(token) == TOKEN_IDENT) {
2455 		struct symbol *s = lookup_keyword(token->ident, NS_KEYWORD);
2456 		if (s && s->op->statement)
2457 			return s->op->statement(token, stmt);
2458 
2459 		if (match_op(token->next, ':')) {
2460 			struct symbol *s = label_symbol(token, 0);
2461 			token = handle_label_attributes(token->next->next, s);
2462 			if (s->stmt) {
2463 				sparse_error(stmt->pos, "label '%s' redefined", show_ident(s->ident));
2464 				// skip the label to avoid multiple definitions
2465 				return statement(token, tree);
2466 			}
2467 			stmt->type = STMT_LABEL;
2468 			stmt->label_identifier = s;
2469 			stmt->label_scope = label_scope;
2470 			if (s->label_scope) {
2471 				if (!is_in_scope(label_scope, s->label_scope))
2472 					warn_label_usage(stmt->pos, s->label_pos, s->ident);
2473 			}
2474 			s->stmt = stmt;
2475 			if (match_op(token, '}')) {
2476 				warning(token->pos, "statement expected after label");
2477 				stmt->label_statement = alloc_statement(token->pos, STMT_NONE);
2478 				return token;
2479 			}
2480 			return statement(token, &stmt->label_statement);
2481 		}
2482 	}
2483 
2484 	if (match_op(token, '{')) {
2485 		token = compound_statement(token->next, stmt);
2486 		return expect(token, '}', "at end of compound statement");
2487 	}
2488 
2489 	stmt->type = STMT_EXPRESSION;
2490 	return expression_statement(token, &stmt->expression);
2491 }
2492 
2493 /* gcc extension - __label__ ident-list; in the beginning of compound stmt */
label_statement(struct token * token)2494 static struct token *label_statement(struct token *token)
2495 {
2496 	while (token_type(token) == TOKEN_IDENT) {
2497 		struct symbol *sym = alloc_symbol(token->pos, SYM_LABEL);
2498 		/* it's block-scope, but we want label namespace */
2499 		bind_symbol_with_scope(sym, token->ident, NS_LABEL, block_scope);
2500 		fn_local_symbol(sym);
2501 		token = token->next;
2502 		if (!match_op(token, ','))
2503 			break;
2504 		token = token->next;
2505 	}
2506 	return expect(token, ';', "at end of label declaration");
2507 }
2508 
statement_list(struct token * token,struct statement_list ** list)2509 static struct token * statement_list(struct token *token, struct statement_list **list)
2510 {
2511 	int seen_statement = 0;
2512 	while (token_type(token) == TOKEN_IDENT &&
2513 	       token->ident == &__label___ident)
2514 		token = label_statement(token->next);
2515 	for (;;) {
2516 		struct statement * stmt;
2517 		if (eof_token(token))
2518 			break;
2519 		if (match_op(token, '}'))
2520 			break;
2521 		if (match_ident(token, &_Static_assert_ident)) {
2522 			token = parse_static_assert(token, NULL);
2523 			continue;
2524 		}
2525 		if (lookup_type(token)) {
2526 			if (seen_statement) {
2527 				warning(token->pos, "mixing declarations and code");
2528 				seen_statement = 0;
2529 			}
2530 			stmt = alloc_statement(token->pos, STMT_DECLARATION);
2531 			token = external_declaration(token, &stmt->declaration, NULL);
2532 		} else {
2533 			seen_statement = Wdeclarationafterstatement;
2534 			token = statement(token, &stmt);
2535 		}
2536 		add_statement(list, stmt);
2537 	}
2538 	return token;
2539 }
2540 
identifier_list(struct token * token,struct symbol * fn)2541 static struct token *identifier_list(struct token *token, struct symbol *fn)
2542 {
2543 	struct symbol_list **list = &fn->arguments;
2544 	for (;;) {
2545 		struct symbol *sym = alloc_symbol(token->pos, SYM_NODE);
2546 		sym->ident = token->ident;
2547 		token = token->next;
2548 		sym->endpos = token->pos;
2549 		sym->ctype.base_type = &incomplete_ctype;
2550 		add_symbol(list, sym);
2551 		if (!match_op(token, ',') ||
2552 		    token_type(token->next) != TOKEN_IDENT ||
2553 		    lookup_type(token->next))
2554 			break;
2555 		token = token->next;
2556 	}
2557 	return token;
2558 }
2559 
parameter_type_list(struct token * token,struct symbol * fn)2560 static struct token *parameter_type_list(struct token *token, struct symbol *fn)
2561 {
2562 	struct symbol_list **list = &fn->arguments;
2563 
2564 	for (;;) {
2565 		struct symbol *sym;
2566 
2567 		if (match_op(token, SPECIAL_ELLIPSIS)) {
2568 			fn->variadic = 1;
2569 			token = token->next;
2570 			break;
2571 		}
2572 
2573 		sym = alloc_symbol(token->pos, SYM_NODE);
2574 		token = parameter_declaration(token, sym);
2575 		if (sym->ctype.base_type == &void_ctype) {
2576 			/* Special case: (void) */
2577 			if (!*list && !sym->ident)
2578 				break;
2579 			warning(token->pos, "void parameter");
2580 		}
2581 		add_symbol(list, sym);
2582 		if (!match_op(token, ','))
2583 			break;
2584 		token = token->next;
2585 	}
2586 	return token;
2587 }
2588 
compound_statement(struct token * token,struct statement * stmt)2589 struct token *compound_statement(struct token *token, struct statement *stmt)
2590 {
2591 	stmt->type = STMT_COMPOUND;
2592 	start_block_scope();
2593 	token = statement_list(token, &stmt->stmts);
2594 	end_block_scope();
2595 	return token;
2596 }
2597 
identifier_expression(struct token * token)2598 static struct expression *identifier_expression(struct token *token)
2599 {
2600 	struct expression *expr = alloc_expression(token->pos, EXPR_IDENTIFIER);
2601 	expr->expr_ident = token->ident;
2602 	return expr;
2603 }
2604 
index_expression(struct expression * from,struct expression * to)2605 static struct expression *index_expression(struct expression *from, struct expression *to)
2606 {
2607 	int idx_from, idx_to;
2608 	struct expression *expr = alloc_expression(from->pos, EXPR_INDEX);
2609 
2610 	idx_from = const_expression_value(from);
2611 	idx_to = idx_from;
2612 	if (to) {
2613 		idx_to = const_expression_value(to);
2614 		if (idx_to < idx_from || idx_from < 0)
2615 			warning(from->pos, "nonsense array initializer index range");
2616 	}
2617 	expr->idx_from = idx_from;
2618 	expr->idx_to = idx_to;
2619 	return expr;
2620 }
2621 
single_initializer(struct expression ** ep,struct token * token)2622 static struct token *single_initializer(struct expression **ep, struct token *token)
2623 {
2624 	int expect_equal = 0;
2625 	struct token *next = token->next;
2626 	struct expression **tail = ep;
2627 	int nested;
2628 
2629 	*ep = NULL;
2630 
2631 	if ((token_type(token) == TOKEN_IDENT) && match_op(next, ':')) {
2632 		struct expression *expr = identifier_expression(token);
2633 		if (Wold_initializer)
2634 			warning(token->pos, "obsolete struct initializer, use C99 syntax");
2635 		token = initializer(&expr->ident_expression, next->next);
2636 		if (expr->ident_expression)
2637 			*ep = expr;
2638 		return token;
2639 	}
2640 
2641 	for (tail = ep, nested = 0; ; nested++, next = token->next) {
2642 		if (match_op(token, '.') && (token_type(next) == TOKEN_IDENT)) {
2643 			struct expression *expr = identifier_expression(next);
2644 			*tail = expr;
2645 			tail = &expr->ident_expression;
2646 			expect_equal = 1;
2647 			token = next->next;
2648 		} else if (match_op(token, '[')) {
2649 			struct expression *from = NULL, *to = NULL, *expr;
2650 			token = constant_expression(token->next, &from);
2651 			if (!from) {
2652 				sparse_error(token->pos, "Expected constant expression");
2653 				break;
2654 			}
2655 			if (match_op(token, SPECIAL_ELLIPSIS))
2656 				token = constant_expression(token->next, &to);
2657 			expr = index_expression(from, to);
2658 			*tail = expr;
2659 			tail = &expr->idx_expression;
2660 			token = expect(token, ']', "at end of initializer index");
2661 			if (nested)
2662 				expect_equal = 1;
2663 		} else {
2664 			break;
2665 		}
2666 	}
2667 	if (nested && !expect_equal) {
2668 		if (!match_op(token, '='))
2669 			warning(token->pos, "obsolete array initializer, use C99 syntax");
2670 		else
2671 			expect_equal = 1;
2672 	}
2673 	if (expect_equal)
2674 		token = expect(token, '=', "at end of initializer index");
2675 
2676 	token = initializer(tail, token);
2677 	if (!*tail)
2678 		*ep = NULL;
2679 	return token;
2680 }
2681 
initializer_list(struct expression_list ** list,struct token * token)2682 static struct token *initializer_list(struct expression_list **list, struct token *token)
2683 {
2684 	struct expression *expr;
2685 
2686 	for (;;) {
2687 		token = single_initializer(&expr, token);
2688 		if (!expr)
2689 			break;
2690 		add_expression(list, expr);
2691 		if (!match_op(token, ','))
2692 			break;
2693 		token = token->next;
2694 	}
2695 	return token;
2696 }
2697 
initializer(struct expression ** tree,struct token * token)2698 struct token *initializer(struct expression **tree, struct token *token)
2699 {
2700 	if (match_op(token, '{')) {
2701 		struct expression *expr = alloc_expression(token->pos, EXPR_INITIALIZER);
2702 		*tree = expr;
2703 		if (!Wuniversal_initializer) {
2704 			struct token *next = token->next;
2705 			// '{ 0 }' is equivalent to '{ }' except for some
2706 			// warnings, like using 0 to initialize a null-pointer.
2707 			if (match_token_zero(next)) {
2708 				if (match_op(next->next, '}'))
2709 					expr->zero_init = 1;
2710 			}
2711 		}
2712 
2713 		token = initializer_list(&expr->expr_list, token->next);
2714 		return expect(token, '}', "at end of initializer");
2715 	}
2716 	return assignment_expression(token, tree);
2717 }
2718 
declare_argument(struct symbol * sym,struct symbol * fn)2719 static void declare_argument(struct symbol *sym, struct symbol *fn)
2720 {
2721 	if (!sym->ident) {
2722 		sparse_error(sym->pos, "no identifier for function argument");
2723 		return;
2724 	}
2725 	if (sym->ctype.base_type == &incomplete_ctype) {
2726 		sym->ctype.base_type = &int_ctype;
2727 
2728 		if (Wimplicit_int) {
2729 			sparse_error(sym->pos, "missing type declaration for parameter '%s'",
2730 				show_ident(sym->ident));
2731 		}
2732 	}
2733 	bind_symbol(sym, sym->ident, NS_SYMBOL);
2734 }
2735 
parse_function_body(struct token * token,struct symbol * decl,struct symbol_list ** list)2736 static struct token *parse_function_body(struct token *token, struct symbol *decl,
2737 	struct symbol_list **list)
2738 {
2739 	struct symbol_list **old_symbol_list;
2740 	struct symbol *base_type = decl->ctype.base_type;
2741 	struct statement *stmt, **p;
2742 	struct symbol *prev;
2743 	struct symbol *arg;
2744 
2745 	old_symbol_list = function_symbol_list;
2746 	if (decl->ctype.modifiers & MOD_INLINE) {
2747 		function_symbol_list = &decl->inline_symbol_list;
2748 		p = &base_type->inline_stmt;
2749 	} else {
2750 		function_symbol_list = &decl->symbol_list;
2751 		p = &base_type->stmt;
2752 	}
2753 	function_computed_target_list = NULL;
2754 	function_computed_goto_list = NULL;
2755 
2756 	if ((decl->ctype.modifiers & (MOD_EXTERN|MOD_INLINE)) == MOD_EXTERN) {
2757 		if (Wexternal_function_has_definition)
2758 			warning(decl->pos, "function '%s' with external linkage has definition", show_ident(decl->ident));
2759 	}
2760 	if (!(decl->ctype.modifiers & MOD_STATIC))
2761 		decl->ctype.modifiers |= MOD_EXTERN;
2762 
2763 	stmt = start_function(decl);
2764 	*p = stmt;
2765 
2766 	FOR_EACH_PTR (base_type->arguments, arg) {
2767 		declare_argument(arg, base_type);
2768 	} END_FOR_EACH_PTR(arg);
2769 
2770 	token = statement_list(token->next, &stmt->stmts);
2771 	end_function(decl);
2772 
2773 	if (!(decl->ctype.modifiers & MOD_INLINE))
2774 		add_symbol(list, decl);
2775 	check_declaration(decl);
2776 	decl->definition = decl;
2777 	prev = decl->same_symbol;
2778 	if (prev && prev->definition) {
2779 		warning(decl->pos, "multiple definitions for function '%s'",
2780 			show_ident(decl->ident));
2781 		info(prev->definition->pos, " the previous one is here");
2782 	} else {
2783 		while (prev) {
2784 			rebind_scope(prev, decl->scope);
2785 			prev->definition = decl;
2786 			prev = prev->same_symbol;
2787 		}
2788 	}
2789 	function_symbol_list = old_symbol_list;
2790 	if (function_computed_goto_list) {
2791 		if (!function_computed_target_list)
2792 			warning(decl->pos, "function '%s' has computed goto but no targets?", show_ident(decl->ident));
2793 		else {
2794 			FOR_EACH_PTR(function_computed_goto_list, stmt) {
2795 				stmt->target_list = function_computed_target_list;
2796 			} END_FOR_EACH_PTR(stmt);
2797 		}
2798 	}
2799 	return expect(token, '}', "at end of function");
2800 }
2801 
promote_k_r_types(struct symbol * arg)2802 static void promote_k_r_types(struct symbol *arg)
2803 {
2804 	struct symbol *base = arg->ctype.base_type;
2805 	if (base && base->ctype.base_type == &int_type && base->rank < 0) {
2806 		arg->ctype.base_type = &int_ctype;
2807 	}
2808 }
2809 
apply_k_r_types(struct symbol_list * argtypes,struct symbol * fn)2810 static void apply_k_r_types(struct symbol_list *argtypes, struct symbol *fn)
2811 {
2812 	struct symbol_list *real_args = fn->ctype.base_type->arguments;
2813 	struct symbol *arg;
2814 
2815 	FOR_EACH_PTR(real_args, arg) {
2816 		struct symbol *type;
2817 
2818 		/* This is quadratic in the number of arguments. We _really_ don't care */
2819 		FOR_EACH_PTR(argtypes, type) {
2820 			if (type->ident == arg->ident)
2821 				goto match;
2822 		} END_FOR_EACH_PTR(type);
2823 		if (Wimplicit_int) {
2824 			warning(arg->pos, "missing type declaration for parameter '%s'",
2825 				show_ident(arg->ident));
2826 		}
2827 		type = alloc_symbol(arg->pos, SYM_NODE);
2828 		type->ident = arg->ident;
2829 		type->ctype.base_type = &int_ctype;
2830 match:
2831 		type->used = 1;
2832 		/* "char" and "short" promote to "int" */
2833 		promote_k_r_types(type);
2834 
2835 		arg->ctype = type->ctype;
2836 	} END_FOR_EACH_PTR(arg);
2837 
2838 	FOR_EACH_PTR(argtypes, arg) {
2839 		if (!arg->used)
2840 			warning(arg->pos, "nonsensical parameter declaration '%s'", show_ident(arg->ident));
2841 	} END_FOR_EACH_PTR(arg);
2842 
2843 }
2844 
parse_k_r_arguments(struct token * token,struct symbol * decl,struct symbol_list ** list)2845 static struct token *parse_k_r_arguments(struct token *token, struct symbol *decl,
2846 	struct symbol_list **list)
2847 {
2848 	struct symbol_list *args = NULL;
2849 
2850 	if (Wold_style_definition)
2851 		warning(token->pos, "non-ANSI definition of function '%s'", show_ident(decl->ident));
2852 
2853 	do {
2854 		token = declaration_list(token, &args);
2855 		if (!match_op(token, ';')) {
2856 			sparse_error(token->pos, "expected ';' at end of parameter declaration");
2857 			break;
2858 		}
2859 		token = token->next;
2860 	} while (lookup_type(token));
2861 
2862 	apply_k_r_types(args, decl);
2863 
2864 	if (!match_op(token, '{')) {
2865 		sparse_error(token->pos, "expected function body");
2866 		return token;
2867 	}
2868 	return parse_function_body(token, decl, list);
2869 }
2870 
toplevel_asm_declaration(struct token * token,struct symbol_list ** list)2871 static struct token *toplevel_asm_declaration(struct token *token, struct symbol_list **list)
2872 {
2873 	struct symbol *anon = alloc_symbol(token->pos, SYM_NODE);
2874 	struct symbol *fn = alloc_symbol(token->pos, SYM_FN);
2875 	struct statement *stmt;
2876 
2877 	anon->ctype.base_type = fn;
2878 	stmt = alloc_statement(token->pos, STMT_NONE);
2879 	fn->stmt = stmt;
2880 
2881 	token = parse_asm_statement(token, stmt);
2882 
2883 	// FIXME: add_symbol(list, anon);
2884 	return token;
2885 }
2886 
external_declaration(struct token * token,struct symbol_list ** list,validate_decl_t validate_decl)2887 struct token *external_declaration(struct token *token, struct symbol_list **list,
2888 		validate_decl_t validate_decl)
2889 {
2890 	struct ident *ident = NULL;
2891 	struct symbol *decl;
2892 	struct decl_state ctx = { .ident = &ident };
2893 	struct ctype saved;
2894 	struct symbol *base_type;
2895 	unsigned long mod;
2896 	int is_typedef;
2897 
2898 	/* Top-level inline asm or static assertion? */
2899 	if (token_type(token) == TOKEN_IDENT) {
2900 		struct symbol *s = lookup_keyword(token->ident, NS_KEYWORD);
2901 		if (s && s->op->toplevel)
2902 			return s->op->toplevel(token, list);
2903 	}
2904 
2905 	/* Parse declaration-specifiers, if any */
2906 	token = declaration_specifiers(token, &ctx);
2907 	mod = decl_modifiers(&ctx);
2908 	decl = alloc_symbol(token->pos, SYM_NODE);
2909 	/* Just a type declaration? */
2910 	if (match_op(token, ';')) {
2911 		apply_modifiers(token->pos, &ctx);
2912 		return token->next;
2913 	}
2914 
2915 	saved = ctx.ctype;
2916 	token = declarator(token, &ctx);
2917 	token = handle_asm_name(token, &ctx);
2918 	token = handle_attributes(token, &ctx);
2919 	apply_modifiers(token->pos, &ctx);
2920 
2921 	decl->ctype = ctx.ctype;
2922 	decl->ctype.modifiers |= mod;
2923 	decl->endpos = token->pos;
2924 
2925 	/* Just a type declaration? */
2926 	if (!ident) {
2927 		warning(token->pos, "missing identifier in declaration");
2928 		return expect(token, ';', "at the end of type declaration");
2929 	}
2930 
2931 	/* type define declaration? */
2932 	is_typedef = ctx.storage_class == MOD_USERTYPE;
2933 
2934 	/* Typedefs don't have meaningful storage */
2935 	if (is_typedef)
2936 		decl->ctype.modifiers |= MOD_USERTYPE;
2937 
2938 	bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
2939 
2940 	base_type = decl->ctype.base_type;
2941 
2942 	if (is_typedef) {
2943 		if (base_type && !base_type->ident) {
2944 			switch (base_type->type) {
2945 			case SYM_STRUCT:
2946 			case SYM_UNION:
2947 			case SYM_ENUM:
2948 			case SYM_RESTRICT:
2949 				base_type->ident = ident;
2950 				break;
2951 			default:
2952 				break;
2953 			}
2954 		}
2955 	} else if (base_type && base_type->type == SYM_FN) {
2956 		if (base_type->ctype.base_type == &autotype_ctype) {
2957 			sparse_error(decl->pos, "'%s()' has __auto_type return type",
2958 				show_ident(decl->ident));
2959 			base_type->ctype.base_type = &int_ctype;
2960 		}
2961 		if (base_type->ctype.base_type == &incomplete_ctype) {
2962 			warning(decl->pos, "'%s()' has implicit return type",
2963 				show_ident(decl->ident));
2964 			base_type->ctype.base_type = &int_ctype;
2965 		}
2966 		/* apply attributes placed after the declarator */
2967 		decl->ctype.modifiers |= ctx.f_modifiers;
2968 
2969 		/* K&R argument declaration? */
2970 		if (lookup_type(token))
2971 			return parse_k_r_arguments(token, decl, list);
2972 		if (match_op(token, '{'))
2973 			return parse_function_body(token, decl, list);
2974 
2975 		if (!(decl->ctype.modifiers & MOD_STATIC))
2976 			decl->ctype.modifiers |= MOD_EXTERN;
2977 	} else if (base_type == &void_ctype && !(decl->ctype.modifiers & MOD_EXTERN)) {
2978 		sparse_error(token->pos, "void declaration");
2979 	}
2980 	if (base_type == &incomplete_ctype) {
2981 		warning(decl->pos, "'%s' has implicit type", show_ident(decl->ident));
2982 		decl->ctype.base_type = &int_ctype;;
2983 	}
2984 
2985 	for (;;) {
2986 		if (!is_typedef && match_op(token, '=')) {
2987 			struct token *next = token->next;
2988 			token = initializer(&decl->initializer, next);
2989 			if (token == next)
2990 				sparse_error(token->pos, "expression expected before '%s'", show_token(token));
2991 		}
2992 		if (!is_typedef) {
2993 			if (validate_decl)
2994 				validate_decl(decl);
2995 
2996 			if (decl->initializer && decl->ctype.modifiers & MOD_EXTERN) {
2997 				warning(decl->pos, "symbol with external linkage has initializer");
2998 				decl->ctype.modifiers &= ~MOD_EXTERN;
2999 			}
3000 
3001 			if (!(decl->ctype.modifiers & (MOD_EXTERN | MOD_INLINE))) {
3002 				add_symbol(list, decl);
3003 				fn_local_symbol(decl);
3004 			}
3005 		}
3006 		check_declaration(decl);
3007 		if (decl->same_symbol) {
3008 			decl->definition = decl->same_symbol->definition;
3009 			decl->op = decl->same_symbol->op;
3010 			if (is_typedef) {
3011 				// TODO: handle -std=c89 --pedantic
3012 				check_duplicates(decl);
3013 			}
3014 		}
3015 
3016 		if (ctx.autotype) {
3017 			const char *msg = NULL;
3018 			if (decl->ctype.base_type != &autotype_ctype)
3019 				msg = "on non-identifier";
3020 			else if (match_op(token, ','))
3021 				msg = "on declaration list";
3022 			else if (!decl->initializer)
3023 				msg = "without initializer";
3024 			else if (decl->initializer->type == EXPR_SYMBOL &&
3025 				 decl->initializer->symbol == decl)
3026 				msg = "on self-init var";
3027 			if (msg) {
3028 				sparse_error(decl->pos, "__auto_type %s", msg);
3029 				decl->ctype.base_type = &bad_ctype;
3030 			}
3031 		}
3032 
3033 		if (!match_op(token, ','))
3034 			break;
3035 
3036 		token = token->next;
3037 		ident = NULL;
3038 		decl = alloc_symbol(token->pos, SYM_NODE);
3039 		ctx.ctype = saved;
3040 		token = handle_attributes(token, &ctx);
3041 		token = declarator(token, &ctx);
3042 		token = handle_asm_name(token, &ctx);
3043 		token = handle_attributes(token, &ctx);
3044 		apply_modifiers(token->pos, &ctx);
3045 		decl->ctype = ctx.ctype;
3046 		decl->ctype.modifiers |= mod;
3047 		decl->endpos = token->pos;
3048 		if (!ident) {
3049 			sparse_error(token->pos, "expected identifier name in type definition");
3050 			return token;
3051 		}
3052 
3053 		if (is_typedef)
3054 			decl->ctype.modifiers |= MOD_USERTYPE;
3055 
3056 		bind_symbol(decl, ident, is_typedef ? NS_TYPEDEF: NS_SYMBOL);
3057 
3058 		/* Function declarations are automatically extern unless specifically static */
3059 		base_type = decl->ctype.base_type;
3060 		if (!is_typedef && base_type && base_type->type == SYM_FN) {
3061 			if (!(decl->ctype.modifiers & MOD_STATIC))
3062 				decl->ctype.modifiers |= MOD_EXTERN;
3063 		}
3064 	}
3065 	return expect(token, ';', "at end of declaration");
3066 }
3067