1/*	$NetBSD: err.c,v 1.244 2024/05/12 18:49:36 rillig Exp $	*/
2
3/*
4 * Copyright (c) 1994, 1995 Jochen Pohl
5 * All Rights Reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by Jochen Pohl for
18 *	The NetBSD Project.
19 * 4. The name of the author may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#if HAVE_NBTOOL_CONFIG_H
35#include "nbtool_config.h"
36#endif
37
38#include <sys/cdefs.h>
39#if defined(__RCSID)
40__RCSID("$NetBSD: err.c,v 1.244 2024/05/12 18:49:36 rillig Exp $");
41#endif
42
43#include <limits.h>
44#include <stdarg.h>
45#include <stdlib.h>
46#include <string.h>
47
48#include "lint1.h"
49
50bool seen_error;
51bool seen_warning;
52
53/* number of syntax errors */
54int sytxerr;
55
56
57static const char *const msgs[] = {
58	"empty declaration",						// 0
59	"old-style declaration; add 'int'",				// 1
60	"empty declaration",						// 2
61	"'%s' declared in parameter declaration list",			// 3
62	"illegal type combination",					// 4
63	"modifying typedef with '%s'; only qualifiers allowed",		// 5
64	"use 'double' instead of 'long float'",				// 6
65	"only one storage class allowed",				// 7
66	"illegal storage class",					// 8
67	"only 'register' is valid as storage class in parameter",	// 9
68	"duplicate '%s'",						// 10
69	"bit-field initializer out of range",				// 11
70	"compiler takes size of function",				// 12
71	"incomplete enum type '%s'",					// 13
72	"",								// 14
73	"function returns illegal type '%s'",				// 15
74	"array of function is illegal",					// 16
75	"null dimension",						// 17
76	"illegal use of 'void'",					// 18
77	"void type for '%s'",						// 19
78	"negative array dimension (%d)",				// 20
79	"redeclaration of formal parameter '%s'",			// 21
80	"incomplete or misplaced function definition",			// 22
81	"undefined label '%s'",						// 23
82	"cannot initialize function '%s'",				// 24
83	"cannot initialize typedef '%s'",				// 25
84	"cannot initialize extern declaration '%s'",			// 26
85	"redeclaration of '%s'",					// 27
86	"redefinition of '%s'",						// 28
87	"'%s' was previously declared extern, becomes static",		// 29
88	"redeclaration of '%s'; C90 or later require static",		// 30
89	"'%s' has incomplete type '%s'",				// 31
90	"type of parameter '%s' defaults to 'int'",			// 32
91	"duplicate member name '%s'",					// 33
92	"nonportable bit-field type '%s'",				// 34
93	"illegal bit-field type '%s'",					// 35
94	"illegal bit-field size: %d",					// 36
95	"zero size bit-field",						// 37
96	"function illegal in structure or union",			// 38
97	"zero-sized array '%s' in struct requires C99 or later",	// 39
98	"",			/* never used */			// 40
99	"bit-field in union is very unusual",				// 41
100	"forward reference to enum type",				// 42
101	"redefinition of '%s' hides earlier one",			// 43
102	"declaration of '%s %s' introduces new type in C90 or later",	// 44
103	"base type is really '%s %s'",					// 45
104	"%s tag '%s' redeclared as %s",					// 46
105	"zero sized %s is a C99 feature",				// 47
106	"enumeration value '%s' overflows",				// 48
107	"anonymous struct/union members is a C11 feature",		// 49
108	"parameter '%s' has function type, should be pointer",		// 50
109	"parameter mismatch: %d declared, %d defined",			// 51
110	"cannot initialize parameter '%s'",				// 52
111	"declared parameter '%s' is missing",				// 53
112	"trailing ',' in enum declaration requires C99 or later",	// 54
113	"integral constant expression expected",			// 55
114	"integral constant too large",					// 56
115	"enumeration constant '%s' hides parameter",			// 57
116	"type of '%s' does not match prototype",			// 58
117	"formal parameter #%d lacks name",				// 59
118	"void must be sole parameter",					// 60
119	"void parameter '%s' cannot have name",				// 61
120	"function prototype parameters must have types",		// 62
121	"prototype does not match old-style definition",		// 63
122	"()-less function definition",					// 64
123	"'%s' has no named members",					// 65
124	"",								// 66
125	"cannot return incomplete type",				// 67
126	"typedef already qualified with '%s'",				// 68
127	"inappropriate qualifiers with 'void'",				// 69
128	"",			/* unused */				// 70
129	"too many characters in character constant",			// 71
130	"typedef declares no type name",				// 72
131	"empty character constant",					// 73
132	"no hex digits follow \\x",					// 74
133	"overflow in hex escape",					// 75
134	"character escape does not fit in character",			// 76
135	"bad octal digit '%c'",						// 77
136	"",			/* unused */				// 78
137	"dubious escape \\%c",						// 79
138	"dubious escape \\%o",						// 80
139	"\\a undefined in traditional C",				// 81
140	"\\x undefined in traditional C",				// 82
141	"storage class after type is obsolescent",			// 83
142	"C90 to C17 require formal parameter before '...'",		// 84
143	"dubious tag declaration '%s %s'",				// 85
144	"automatic '%s' hides external declaration",			// 86
145	"static '%s' hides external declaration",			// 87
146	"typedef '%s' hides external declaration",			// 88
147	"typedef '%s' redeclared",					// 89
148	"inconsistent redeclaration of extern '%s'",			// 90
149	"declaration of '%s' hides parameter",				// 91
150	"inconsistent redeclaration of static '%s'",			// 92
151	"dubious static function '%s' at block level",			// 93
152	"function '%s' has illegal storage class",			// 94
153	"declaration of '%s' hides earlier one",			// 95
154	"cannot dereference non-pointer type '%s'",			// 96
155	"suffix 'U' is illegal in traditional C",			// 97
156	"suffixes 'F' and 'L' are illegal in traditional C",		// 98
157	"'%s' undefined",						// 99
158	"unary '+' is illegal in traditional C",			// 100
159	"type '%s' does not have member '%s'",				// 101
160	"illegal use of member '%s'",					// 102
161	"left operand of '.' must be struct or union, not '%s'",	// 103
162	"left operand of '->' must be pointer to struct or union, not '%s'", // 104
163	"non-unique member requires struct/union %s",			// 105
164	"left operand of '->' must be pointer",				// 106
165	"operands of '%s' have incompatible types '%s' and '%s'",	// 107
166	"operand of '%s' has invalid type '%s'",			// 108
167	"void type illegal in expression",				// 109
168	"pointer to function is not allowed here",			// 110
169	"unacceptable operand of '%s'",					// 111
170	"cannot take address of bit-field",				// 112
171	"cannot take address of register '%s'",				// 113
172	"%soperand of '%s' must be lvalue",				// 114
173	"%soperand of '%s' must be modifiable lvalue",			// 115
174	"illegal pointer subtraction",					// 116
175	"bitwise '%s' on signed value possibly nonportable",		// 117
176	"semantics of '%s' change in C90; use explicit cast",		// 118
177	"conversion of '%s' to '%s' is out of range",			// 119
178	"bitwise '%s' on signed value nonportable",			// 120
179	"negative shift",						// 121
180	"shift amount %llu is greater than bit-size %llu of '%s'",	// 122
181	"illegal combination of %s '%s' and %s '%s', op '%s'",		// 123
182	"illegal combination of '%s' and '%s', op '%s'",		// 124
183	"pointers to functions can only be compared for equality",	// 125
184	"incompatible types '%s' and '%s' in conditional",		// 126
185	"'&' before array or function: ignored",			// 127
186	"operands of '%s' have incompatible pointer types to '%s' and '%s'", // 128
187	"expression has null effect",					// 129
188	"enum type mismatch: '%s' '%s' '%s'",				// 130
189	"conversion to '%s' may sign-extend incorrectly",		// 131
190	"conversion from '%s' to '%s' may lose accuracy",		// 132
191	"conversion of pointer to '%s' loses bits",			// 133
192	"conversion of pointer to '%s' may lose bits",			// 134
193	"converting '%s' to '%s' increases alignment from %u to %u",	// 135
194	"cannot do pointer arithmetic on operand of unknown size",	// 136
195	"",			/* unused */				// 137
196	"unknown operand size, op '%s'",				// 138
197	"division by 0",						// 139
198	"modulus by 0",							// 140
199	"'%s' overflows '%s'",						// 141
200	"operator '%s' produces floating point overflow",		// 142
201	"cannot take size/alignment of incomplete type",		// 143
202	"cannot take size/alignment of function type '%s'",		// 144
203	"cannot take size/alignment of bit-field",			// 145
204	"cannot take size/alignment of void",				// 146
205	"invalid cast from '%s' to '%s'",				// 147
206	"improper cast of void expression",				// 148
207	"cannot call '%s', must be a function",				// 149
208	"argument mismatch: %d %s passed, %d expected",			// 150
209	"void expressions may not be arguments, arg #%d",		// 151
210	"argument cannot have unknown size, arg #%d",			// 152
211	"converting '%s' to incompatible '%s' for argument %d",		// 153
212	"illegal combination of %s '%s' and %s '%s', arg #%d",		// 154
213	"passing '%s' to incompatible '%s', arg #%d",			// 155
214	"function expects '%s', passing '%s' for arg #%d",		// 156
215	"C90 treats constant as unsigned",				// 157
216	"'%s' may be used before set",					// 158
217	"assignment in conditional context",				// 159
218	"operator '==' found where '=' was expected",			// 160
219	"constant in conditional context",				// 161
220	"operator '%s' compares '%s' with '%s'",			// 162
221	"a cast does not yield an lvalue",				// 163
222	"assignment of negative constant to unsigned type",		// 164
223	"constant truncated by assignment",				// 165
224	"precision lost in bit-field assignment",			// 166
225	"array subscript %jd cannot be negative",			// 167
226	"array subscript %ju cannot be > %d",				// 168
227	"precedence confusion possible: parenthesize!",			// 169
228	"first operand of '?' must have scalar type",			// 170
229	"cannot assign to '%s' from '%s'",				// 171
230	"too many struct/union initializers",				// 172
231	"too many array initializers, expected %d",			// 173
232	"too many initializers for '%s'",				// 174
233	"initialization of incomplete type '%s'",			// 175
234	"",			/* no longer used */			// 176
235	"non-constant initializer",					// 177
236	"initializer does not fit",					// 178
237	"cannot initialize struct/union with no named member",		// 179
238	"bit-field initializer does not fit",				// 180
239	"{}-enclosed or constant initializer of type '%s' required",	// 181
240	"incompatible pointer types to '%s' and '%s'",			// 182
241	"illegal combination of %s '%s' and %s '%s'",			// 183
242	"illegal combination of '%s' and '%s'",				// 184
243	"cannot initialize '%s' from '%s'",				// 185
244	"bit-field initializer must be an integer in traditional C",	// 186
245	"string literal too long (%ju) for target array (%ju)",		// 187
246	"no automatic aggregate initialization in traditional C",	// 188
247	"",			/* no longer used */			// 189
248	"empty array declaration for '%s'",				// 190
249	"'%s' set but not used in function '%s'",			// 191
250	"'%s' unused in function '%s'",					// 192
251	"statement not reached",					// 193
252	"label '%s' redefined",						// 194
253	"case not in switch",						// 195
254	"case label affected by conversion",				// 196
255	"non-constant case expression",					// 197
256	"non-integral case expression",					// 198
257	"duplicate case '%jd' in switch",				// 199
258	"duplicate case '%ju' in switch",				// 200
259	"default outside switch",					// 201
260	"duplicate default in switch",					// 202
261	"case label must be of type 'int' in traditional C",		// 203
262	"controlling expressions must have scalar type",		// 204
263	"switch expression must have integral type",			// 205
264	"enumeration value(s) not handled in switch",			// 206
265	"loop not entered at top",					// 207
266	"break outside loop or switch",					// 208
267	"continue outside loop",					// 209
268	"enum type mismatch between '%s' and '%s' in initialization",	// 210
269	"function has return type '%s' but returns '%s'",		// 211
270	"cannot return incomplete type",				// 212
271	"void function '%s' cannot return value",			// 213
272	"function '%s' expects to return value",			// 214
273	"function '%s' implicitly declared to return int",		// 215
274	"function '%s' has 'return expr' and 'return'",			// 216
275	"function '%s' falls off bottom without returning value",	// 217
276	"C90 treats constant as unsigned, op '%s'",			// 218
277	"concatenated strings are illegal in traditional C",		// 219
278	"fallthrough on case statement",				// 220
279	"initialization of unsigned with negative constant",		// 221
280	"conversion of negative constant to unsigned type",		// 222
281	"end-of-loop code not reached",					// 223
282	"cannot recover from previous errors",				// 224
283	"static function '%s' called but not defined",			// 225
284	"static variable '%s' unused",					// 226
285	"const object '%s' should have initializer",			// 227
286	"function cannot return const or volatile object",		// 228
287	"converting '%s' to '%s' is questionable",			// 229
288	"nonportable character comparison '%s'",			// 230
289	"parameter '%s' unused in function '%s'",			// 231
290	"label '%s' unused in function '%s'",				// 232
291	"struct '%s' never defined",					// 233
292	"union '%s' never defined",					// 234
293	"enum '%s' never defined",					// 235
294	"static function '%s' unused",					// 236
295	"redeclaration of formal parameter '%s'",			// 237
296	"initialization of union is illegal in traditional C",		// 238
297	"constant operand to '!'",					// 239
298	"",			/* unused */				// 240
299	"dubious operation '%s' on enum",				// 241
300	"combination of '%s' and '%s', op '%s'",			// 242
301	"operator '%s' assumes that '%s' is ordered",			// 243
302	"illegal structure pointer combination",			// 244
303	"incompatible structure pointers: '%s' '%s' '%s'",		// 245
304	"dubious conversion of enum to '%s'",				// 246
305	"pointer cast from '%s' to '%s' may be troublesome",		// 247
306	"floating-point constant out of range",				// 248
307	"syntax error '%s'",						// 249
308	"unknown character \\%o",					// 250
309	"malformed integer constant",					// 251
310	"integer constant out of range",				// 252
311	"unterminated character constant",				// 253
312	"newline in string or char constant",				// 254
313	"undefined or invalid '#' directive",				// 255
314	"unterminated comment",						// 256
315	"extra characters in lint comment",				// 257
316	"unterminated string constant",					// 258
317	"argument %d is converted from '%s' to '%s' due to prototype",	// 259
318	"previous declaration of '%s'",					// 260
319	"previous definition of '%s'",					// 261
320	"\\\" inside character constants undefined in traditional C",	// 262
321	"\\? undefined in traditional C",				// 263
322	"\\v undefined in traditional C",				// 264
323	"%s does not support 'long long'",				// 265
324	"'long double' is illegal in traditional C",			// 266
325	"shift amount %u equals bit-size of '%s'",			// 267
326	"variable '%s' declared inline",				// 268
327	"parameter '%s' declared inline",				// 269
328	"function prototypes are illegal in traditional C",		// 270
329	"switch expression must be of type 'int' in traditional C",	// 271
330	"empty translation unit",					// 272
331	"bit-field type '%s' invalid in C90 or later",			// 273
332	"C90 or later forbid comparison of %s with %s",			// 274
333	"cast discards 'const' from type '%s'",				// 275
334	"'__%s__' is illegal for type '%s'",				// 276
335	"initialization of '%s' with '%s'",				// 277
336	"combination of '%s' and '%s', arg #%d",			// 278
337	"combination of '%s' and '%s' in return",			// 279
338	"comment /* %s */ must be outside function",			// 280
339	"duplicate comment /* %s */",					// 281
340	"comment /* %s */ must precede function definition",		// 282
341	"parameter number mismatch in comment /* %s */",		// 283
342	"fallthrough on default statement",				// 284
343	"prototype declaration",					// 285
344	"function definition is not a prototype",			// 286
345	"function declaration is not a prototype",			// 287
346	"dubious use of /* VARARGS */ with /* %s */",			// 288
347	"/* PRINTFLIKE */ and /* SCANFLIKE */ cannot be combined",	// 289
348	"static function '%s' declared but not defined",		// 290
349	"invalid multibyte character",					// 291
350	"cannot concatenate wide and regular string literals",		// 292
351	"parameter %d must be 'char *' for PRINTFLIKE/SCANFLIKE",	// 293
352	"multi-character character constant",				// 294
353	"conversion of '%s' to '%s' is out of range, arg #%d",		// 295
354	"conversion of negative constant to unsigned type, arg #%d",	// 296
355	"conversion to '%s' may sign-extend incorrectly, arg #%d",	// 297
356	"conversion from '%s' to '%s' may lose accuracy, arg #%d",	// 298
357	"prototype does not match old-style definition, arg #%d",	// 299
358	"old-style definition",						// 300
359	"array of incomplete type",					// 301
360	"'%s' returns pointer to automatic object",			// 302
361	"conversion of %s to %s requires a cast",			// 303
362	"conversion of %s to %s requires a cast, arg #%d",		// 304
363	"conversion of %s to %s requires a cast, op %s",		// 305
364	"constant truncated by conversion, op '%s'",			// 306
365	"static variable '%s' set but not used",			// 307
366	"invalid type for _Complex",					// 308
367	"extra bits set to 0 in conversion of '%s' to '%s', op '%s'",	// 309
368	"symbol renaming can't be used on function parameters",		// 310
369	"symbol renaming can't be used on automatic variables",		// 311
370	"%s does not support '//' comments",				// 312
371	"struct or union member name in initializer is a C99 feature",	// 313
372	"",		/* never used */				// 314
373	"GCC style struct or union member name in initializer",		// 315
374	"__FUNCTION__/__PRETTY_FUNCTION__ is a GCC extension",		// 316
375	"__func__ is a C99 feature",					// 317
376	"variable array dimension is a C99/GCC extension",		// 318
377	"compound literals are a C99/GCC extension",			// 319
378	"'({ ... })' is a GCC extension",				// 320
379	"array initializer with designators is a C99 feature",		// 321
380	"zero sized array requires C99 or later",			// 322
381	"continue in 'do ... while (0)' loop",				// 323
382	"suggest cast from '%s' to '%s' on op '%s' to avoid overflow",	// 324
383	"variable declaration in for loop",				// 325
384	"attribute '%s' ignored for '%s'",				// 326
385	"declarations after statements is a C99 feature",		// 327
386	"union cast is a GCC extension",				// 328
387	"type '%s' is not a member of '%s'",				// 329
388	"operand of '%s' must be bool, not '%s'",			// 330
389	"left operand of '%s' must be bool, not '%s'",			// 331
390	"right operand of '%s' must be bool, not '%s'",			// 332
391	"controlling expression must be bool, not '%s'",		// 333
392	"parameter %d expects '%s', gets passed '%s'",			// 334
393	"operand of '%s' must not be bool",				// 335
394	"left operand of '%s' must not be bool",			// 336
395	"right operand of '%s' must not be bool",			// 337
396	"option '%c' should be handled in the switch",			// 338
397	"option '%c' should be listed in the options string",		// 339
398	"initialization with '[a...b]' is a GCC extension",		// 340
399	"argument to '%s' must be 'unsigned char' or EOF, not '%s'",	// 341
400	"argument to '%s' must be cast to 'unsigned char', not to '%s'", // 342
401	"static array size requires C11 or later",			// 343
402	"bit-field of type plain 'int' has implementation-defined signedness", // 344
403	"generic selection requires C11 or later",			// 345
404	"call to '%s' effectively discards 'const' from argument",	// 346
405	"redeclaration of '%s' with type '%s', expected '%s'",		// 347
406	"maximum value %d of '%s' does not match maximum array index %d", // 348
407	"non type argument to alignof is a GCC extension",		// 349
408	"'_Atomic' requires C11 or later",				// 350
409	"missing%s header declaration for '%s'",			// 351
410	"nested 'extern' declaration of '%s'",				// 352
411	"empty initializer braces require C23 or later",		// 353
412	"'_Static_assert' requires C11 or later",			// 354
413	"'_Static_assert' without message requires C23 or later",	// 355
414	"short octal escape '%.*s' followed by digit '%c'",		// 356
415	"hex escape '%.*s' mixes uppercase and lowercase digits",	// 357
416	"hex escape '%.*s' has more than 2 digits",			// 358
417	"missing new-style '\\177' or old-style number base",		// 359
418	"missing new-style number base after '\\177'",			// 360
419	"number base '%.*s' is %ju, must be 8, 10 or 16",		// 361
420	"conversion '%.*s' should not be escaped",			// 362
421	"escaped character '%.*s' in description of conversion '%.*s'", // 363
422	"missing bit position after '%.*s'",				// 364
423	"missing field width after '%.*s'",				// 365
424	"missing '\\0' at the end of '%.*s'",				// 366
425	"empty description in '%.*s'",					// 367
426	"missing comparison value after conversion '%.*s'",		// 368
427	"bit position '%.*s' in '%.*s' should be escaped as octal or hex", // 369
428	"field width '%.*s' in '%.*s' should be escaped as octal or hex", // 370
429	"bit position '%.*s' (%ju) in '%.*s' out of range %u..%u",	// 371
430	"field width '%.*s' (%ju) in '%.*s' out of range 0..64",	// 372
431	"bit field end %ju in '%.*s' out of range 0..64",		// 373
432	"unknown conversion '%.*s', must be one of 'bfF=:*'",		// 374
433	"comparison value '%.*s' (%ju) exceeds maximum field value %ju", // 375
434	"'%.*s' overlaps earlier '%.*s' on bit %u",			// 376
435	"redundant '\\0' at the end of the format",			// 377
436	"conversion '%.*s' is unreachable by input value",		// 378
437	"comparing integer '%s' to floating point constant %Lg",	// 379
438};
439
440static bool is_suppressed[sizeof(msgs) / sizeof(msgs[0])];
441
442static struct include_level {
443	const char *filename;
444	int lineno;
445	struct include_level *by;
446} *includes;
447
448void
449suppress_messages(const char *p)
450{
451	char *end;
452
453	for (; ch_isdigit(*p); p = end + 1) {
454		unsigned long id = strtoul(p, &end, 10);
455		if ((*end != '\0' && *end != ',') ||
456		    id >= sizeof(msgs) / sizeof(msgs[0]) ||
457		    msgs[id][0] == '\0')
458			break;
459
460		is_suppressed[id] = true;
461
462		if (*end == '\0')
463			return;
464	}
465	errx(1, "invalid message ID '%.*s'", (int)strcspn(p, ","), p);
466}
467
468void
469update_location(const char *filename, int lineno, bool is_begin, bool is_end)
470{
471	struct include_level *top;
472
473	top = includes;
474	if (is_begin && top != NULL)
475		top->lineno = curr_pos.p_line;
476
477	if (top == NULL || is_begin) {
478		top = xmalloc(sizeof(*top));
479		top->filename = filename;
480		top->lineno = lineno;
481		top->by = includes;
482		includes = top;
483	} else {
484		if (is_end) {
485			includes = top->by;
486			free(top);
487			top = includes;
488		}
489		if (top != NULL) {
490			top->filename = filename;
491			top->lineno = lineno;
492		}
493	}
494}
495
496static void
497print_stack_trace(void)
498{
499	const struct include_level *top;
500
501	if ((top = includes) == NULL)
502		return;
503	/*
504	 * Skip the innermost include level since it is already listed in the
505	 * diagnostic itself.  Furthermore, its lineno is the line number of
506	 * the last '#' line, not the current line.
507	 */
508	for (top = top->by; top != NULL; top = top->by)
509		printf("\tincluded from %s(%d)\n", top->filename, top->lineno);
510}
511
512/*
513 * If Fflag is not set, lbasename() returns a pointer to the last
514 * component of the path, otherwise it returns the argument.
515 */
516static const char *
517lbasename(const char *path)
518{
519
520	if (Fflag)
521		return path;
522
523	const char *base = path;
524	for (const char *p = path; *p != '\0'; p++)
525		if (*p == '/')
526			base = p + 1;
527	return base;
528}
529
530static FILE *
531output_channel(void)
532{
533	return yflag ? stderr : stdout;
534}
535
536static void
537verror_at(int msgid, const pos_t *pos, va_list ap)
538{
539
540	if (is_suppressed[msgid])
541		return;
542
543	FILE *out = output_channel();
544	(void)fprintf(out, "%s(%d): error: ",
545	    lbasename(pos->p_file), pos->p_line);
546	(void)vfprintf(out, msgs[msgid], ap);
547	(void)fprintf(out, " [%d]\n", msgid);
548	seen_error = true;
549	print_stack_trace();
550}
551
552static void
553vwarning_at(int msgid, const pos_t *pos, va_list ap)
554{
555
556	if (is_suppressed[msgid])
557		return;
558
559	debug_step("%s: lwarn=%d msgid=%d", __func__, lwarn, msgid);
560	if (lwarn == LWARN_NONE || lwarn == msgid)
561		/* this warning is suppressed by a LINTED comment */
562		return;
563
564	FILE *out = output_channel();
565	(void)fprintf(out, "%s(%d): warning: ",
566	    lbasename(pos->p_file), pos->p_line);
567	(void)vfprintf(out, msgs[msgid], ap);
568	(void)fprintf(out, " [%d]\n", msgid);
569	seen_warning = true;
570	print_stack_trace();
571}
572
573static void
574vmessage_at(int msgid, const pos_t *pos, va_list ap)
575{
576
577	if (is_suppressed[msgid])
578		return;
579
580	FILE *out = output_channel();
581	(void)fprintf(out, "%s(%d): ",
582	    lbasename(pos->p_file), pos->p_line);
583	(void)vfprintf(out, msgs[msgid], ap);
584	(void)fprintf(out, " [%d]\n", msgid);
585	print_stack_trace();
586}
587
588void
589(error_at)(int msgid, const pos_t *pos, ...)
590{
591	va_list ap;
592
593	va_start(ap, pos);
594	verror_at(msgid, pos, ap);
595	va_end(ap);
596}
597
598void
599(error)(int msgid, ...)
600{
601	va_list ap;
602
603	va_start(ap, msgid);
604	verror_at(msgid, &curr_pos, ap);
605	va_end(ap);
606}
607
608void
609assert_failed(const char *file, int line, const char *func, const char *cond)
610{
611
612	/*
613	 * After encountering a parse error in the grammar, lint often does not
614	 * properly clean up its data structures, especially in 'dcs', the
615	 * stack of declaration levels.  This often leads to assertion
616	 * failures.  These cases are not interesting though, as the purpose of
617	 * lint is to check syntactically valid code.  In such a case, exit
618	 * gracefully.  This allows a fuzzer like afl to focus on more
619	 * interesting cases instead of reporting nonsense translation units
620	 * like 'f=({e:;}' or 'v(const(char););e(v){'.
621	 */
622	if (sytxerr > 0)
623		norecover();
624
625	(void)fflush(stdout);
626	(void)fprintf(stderr,
627	    "lint: assertion \"%s\" failed in %s at %s:%d near %s:%d\n",
628	    cond, func, file, line,
629	    lbasename(curr_pos.p_file), curr_pos.p_line);
630	print_stack_trace();
631	(void)fflush(stdout);
632	abort();
633}
634
635void
636(warning_at)(int msgid, const pos_t *pos, ...)
637{
638	va_list ap;
639
640	va_start(ap, pos);
641	vwarning_at(msgid, pos, ap);
642	va_end(ap);
643}
644
645void
646(warning)(int msgid, ...)
647{
648	va_list ap;
649
650	va_start(ap, msgid);
651	vwarning_at(msgid, &curr_pos, ap);
652	va_end(ap);
653}
654
655void
656(message_at)(int msgid, const pos_t *pos, ...)
657{
658	va_list ap;
659
660	va_start(ap, pos);
661	vmessage_at(msgid, pos, ap);
662	va_end(ap);
663}
664
665void
666(c99ism)(int msgid, ...)
667{
668	va_list ap;
669
670	if (allow_c99)
671		return;
672
673	va_start(ap, msgid);
674	int severity = (!allow_gcc ? 1 : 0) + (!allow_trad ? 1 : 0);
675	if (severity == 2)
676		verror_at(msgid, &curr_pos, ap);
677	if (severity == 1)
678		vwarning_at(msgid, &curr_pos, ap);
679	va_end(ap);
680}
681
682void
683(c11ism)(int msgid, ...)
684{
685	va_list ap;
686
687	/* FIXME: C11 mode has nothing to do with GCC mode. */
688	if (allow_c11 || allow_gcc)
689		return;
690	va_start(ap, msgid);
691	verror_at(msgid, &curr_pos, ap);
692	va_end(ap);
693}
694
695void
696(c23ism)(int msgid, ...)
697{
698	va_list ap;
699
700	if (allow_c23)
701		return;
702	va_start(ap, msgid);
703	verror_at(msgid, &curr_pos, ap);
704	va_end(ap);
705}
706
707bool
708(gnuism)(int msgid, ...)
709{
710	va_list ap;
711	int severity = (!allow_gcc ? 1 : 0) +
712	    (!allow_trad && !allow_c99 ? 1 : 0);
713
714	va_start(ap, msgid);
715	if (severity == 2)
716		verror_at(msgid, &curr_pos, ap);
717	if (severity == 1)
718		vwarning_at(msgid, &curr_pos, ap);
719	va_end(ap);
720	return severity > 0;
721}
722
723
724static const char *queries[] = {
725	"",			/* unused, to make queries 1-based */
726	"implicit conversion from floating point '%s' to integer '%s'",	// Q1
727	"cast from floating point '%s' to integer '%s'",		// Q2
728	"implicit conversion changes sign from '%s' to '%s'",		// Q3
729	"usual arithmetic conversion for '%s' from '%s' to '%s'",	// Q4
730	"pointer addition has integer on the left-hand side",		// Q5
731	"no-op cast from '%s' to '%s'",					// Q6
732	"redundant cast from '%s' to '%s' before assignment",		// Q7
733	"octal number '%.*s'",						// Q8
734	"parenthesized return value",					// Q9
735	"chained assignment with '%s' and '%s'",			// Q10
736	"static variable '%s' in function",				// Q11
737	"comma operator with types '%s' and '%s'",			// Q12
738	"redundant 'extern' in function declaration of '%s'",		// Q13
739	"comparison '%s' of 'char' with plain integer %d",		// Q14
740	"implicit conversion from integer 0 to pointer '%s'",		// Q15
741	"'%s' was declared 'static', now non-'static'",			// Q16
742	"invisible character U+%04X in %s",				// Q17
743	"const automatic variable '%s'",				// Q18
744	"implicit conversion from integer '%s' to floating point '%s'",	// Q19
745	"implicit narrowing conversion from void pointer to '%s'",	// Q20
746};
747
748bool any_query_enabled;		/* for optimizing non-query scenarios */
749bool is_query_enabled[sizeof(queries) / sizeof(queries[0])];
750
751void
752(query_message)(int query_id, ...)
753{
754
755	if (!is_query_enabled[query_id])
756		return;
757
758	va_list ap;
759	FILE *out = output_channel();
760	(void)fprintf(out, "%s(%d): ",
761	    lbasename(curr_pos.p_file), curr_pos.p_line);
762	va_start(ap, query_id);
763	(void)vfprintf(out, queries[query_id], ap);
764	va_end(ap);
765	(void)fprintf(out, " [Q%d]\n", query_id);
766	print_stack_trace();
767}
768
769void
770enable_queries(const char *p)
771{
772	char *end;
773
774	for (; ch_isdigit(*p); p = end + 1) {
775		unsigned long id = strtoul(p, &end, 10);
776		if ((*end != '\0' && *end != ',') ||
777		    id >= sizeof(queries) / sizeof(queries[0]) ||
778		    queries[id][0] == '\0')
779			break;
780
781		any_query_enabled = true;
782		is_query_enabled[id] = true;
783
784		if (*end == '\0')
785			return;
786	}
787	errx(1, "invalid query ID '%.*s'", (int)strcspn(p, ","), p);
788}
789