xref: /netbsd-src/usr.bin/xlint/lint2/chk.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /* $NetBSD: chk.c,v 1.11 2001/07/26 15:05:10 wiz Exp $ */
2 
3 /*
4  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
5  * Copyright (c) 1994, 1995 Jochen Pohl
6  * All Rights Reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by Jochen Pohl for
19  *	The NetBSD Project.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #ifndef lint
37 __RCSID("$NetBSD: chk.c,v 1.11 2001/07/26 15:05:10 wiz Exp $");
38 #endif
39 
40 #include <stdlib.h>
41 #include <ctype.h>
42 #include <limits.h>
43 #include <err.h>
44 
45 #include "lint2.h"
46 
47 /* various type information */
48 ttab_t	ttab[NTSPEC];
49 
50 
51 static	void	chkund(hte_t *);
52 static	void	chkdnu(hte_t *);
53 static	void	chkdnud(hte_t *);
54 static	void	chkmd(hte_t *);
55 static	void	chkvtui(hte_t *, sym_t *, sym_t *);
56 static	void	chkvtdi(hte_t *, sym_t *, sym_t *);
57 static	void	chkfaui(hte_t *, sym_t *, sym_t *);
58 static	void	chkau(hte_t *, int, sym_t *, sym_t *, pos_t *,
59 			   fcall_t *, fcall_t *, type_t *, type_t *);
60 static	void	chkrvu(hte_t *, sym_t *);
61 static	void	chkadecl(hte_t *, sym_t *, sym_t *);
62 static	void	printflike(hte_t *,fcall_t *, int, const char *, type_t **);
63 static	void	scanflike(hte_t *, fcall_t *, int, const char *, type_t **);
64 static	void	badfmt(hte_t *, fcall_t *);
65 static	void	inconarg(hte_t *, fcall_t *, int);
66 static	void	tofewarg(hte_t *, fcall_t *);
67 static	void	tomanyarg(hte_t *, fcall_t *);
68 static	int	eqtype(type_t *, type_t *, int, int, int, int *);
69 static	int	eqargs(type_t *, type_t *, int *);
70 static	int	mnoarg(type_t *, int *);
71 
72 
73 void
74 inittyp(void)
75 {
76 	int	i;
77 	static	struct {
78 		tspec_t	it_tspec;
79 		ttab_t	it_ttab;
80 	} ittab[] = {
81 		{ SIGNED,   { 0, 0,
82 				      SIGNED, UNSIGN,
83 				      0, 0, 0, 0, 0, "signed" } },
84 		{ UNSIGN,   { 0, 0,
85 				      SIGNED, UNSIGN,
86 				      0, 0, 0, 0, 0, "unsigned" } },
87 		{ CHAR,	    { CHAR_BIT, CHAR_BIT,
88 				      SCHAR, UCHAR,
89 				      1, 0, 0, 1, 1, "char" } },
90 		{ SCHAR,    { CHAR_BIT, CHAR_BIT,
91 				      SCHAR, UCHAR,
92 				      1, 0, 0, 1, 1, "signed char" } },
93 		{ UCHAR,    { CHAR_BIT, CHAR_BIT,
94 				      SCHAR, UCHAR,
95 				      1, 1, 0, 1, 1, "unsigned char" } },
96 		{ SHORT,    { sizeof (short) * CHAR_BIT, 2 * CHAR_BIT,
97 				      SHORT, USHORT,
98 				      1, 0, 0, 1, 1, "short" } },
99 		{ USHORT,   { sizeof (u_short) * CHAR_BIT, 2 * CHAR_BIT,
100 				      SHORT, USHORT,
101 				      1, 1, 0, 1, 1, "unsigned short" } },
102 		{ INT,      { sizeof (int) * CHAR_BIT, 3 * CHAR_BIT,
103 				      INT, UINT,
104 				      1, 0, 0, 1, 1, "int" } },
105 		{ UINT,     { sizeof (u_int) * CHAR_BIT, 3 * CHAR_BIT,
106 				      INT, UINT,
107 				      1, 1, 0, 1, 1, "unsigned int" } },
108 		{ LONG,     { sizeof (long) * CHAR_BIT, 4 * CHAR_BIT,
109 				      LONG, ULONG,
110 				      1, 0, 0, 1, 1, "long" } },
111 		{ ULONG,    { sizeof (u_long) * CHAR_BIT, 4 * CHAR_BIT,
112 				      LONG, ULONG,
113 				      1, 1, 0, 1, 1, "unsigned long" } },
114 		{ QUAD,     { sizeof (quad_t) * CHAR_BIT, 8 * CHAR_BIT,
115 				      QUAD, UQUAD,
116 				      1, 0, 0, 1, 1, "long long" } },
117 		{ UQUAD,    { sizeof (u_quad_t) * CHAR_BIT, 8 * CHAR_BIT,
118 				      QUAD, UQUAD,
119 				      1, 1, 0, 1, 1, "unsigned long long" } },
120 		{ FLOAT,    { sizeof (float) * CHAR_BIT, 4 * CHAR_BIT,
121 				      FLOAT, FLOAT,
122 				      0, 0, 1, 1, 1, "float" } },
123 		{ DOUBLE,   { sizeof (double) * CHAR_BIT, 8 * CHAR_BIT,
124 				      DOUBLE, DOUBLE,
125 				      0, 0, 1, 1, 1, "double" } },
126 		{ LDOUBLE,  { sizeof (ldbl_t) * CHAR_BIT, 10 * CHAR_BIT,
127 				      LDOUBLE, LDOUBLE,
128 				      0, 0, 1, 1, 1, "long double" } },
129 		{ VOID,     { -1, -1,
130 				      VOID, VOID,
131 				      0, 0, 0, 0, 0, "void" } },
132 		{ STRUCT,   { -1, -1,
133 				      STRUCT, STRUCT,
134 				      0, 0, 0, 0, 0, "struct" } },
135 		{ UNION,    { -1, -1,
136 				      UNION, UNION,
137 				      0, 0, 0, 0, 0, "union" } },
138 		{ ENUM,     { sizeof (int) * CHAR_BIT, 3 * CHAR_BIT,
139 				      ENUM, ENUM,
140 				      1, 0, 0, 1, 1, "enum" } },
141 		{ PTR,      { sizeof (void *) * CHAR_BIT, 4 * CHAR_BIT,
142 				      PTR, PTR,
143 				      0, 1, 0, 0, 1, "pointer" } },
144 		{ ARRAY,    { -1, -1,
145 				      ARRAY, ARRAY,
146 				      0, 0, 0, 0, 0, "array" } },
147 		{ FUNC,     { -1, -1,
148 				      FUNC, FUNC,
149 				      0, 0, 0, 0, 0, "function" } },
150 	};
151 
152 	for (i = 0; i < sizeof (ittab) / sizeof (ittab[0]); i++)
153 		STRUCT_ASSIGN(ttab[ittab[i].it_tspec], ittab[i].it_ttab);
154 	if (!pflag) {
155 		for (i = 0; i < NTSPEC; i++)
156 			ttab[i].tt_psz = ttab[i].tt_sz;
157 	}
158 }
159 
160 
161 /*
162  * If there is a symbol named "main", mark it as used.
163  */
164 void
165 mainused(void)
166 {
167 	hte_t	*hte;
168 
169 	if ((hte = hsearch("main", 0)) != NULL)
170 		hte->h_used = 1;
171 }
172 
173 /*
174  * Performs all tests for a single name
175  */
176 void
177 chkname(hte_t *hte)
178 {
179 	sym_t	*sym, *def, *pdecl, *decl;
180 
181 	if (uflag) {
182 		chkund(hte);
183 		chkdnu(hte);
184 		if (xflag)
185 			chkdnud(hte);
186 	}
187 	chkmd(hte);
188 
189 	/* Get definition, prototype declaration and declaration */
190 	def = pdecl = decl = NULL;
191 	for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) {
192 		if (def == NULL && (sym->s_def == DEF || sym->s_def == TDEF))
193 			def = sym;
194 		if (pdecl == NULL && sym->s_def == DECL &&
195 		    TP(sym->s_type)->t_tspec == FUNC &&
196 		    TP(sym->s_type)->t_proto) {
197 			pdecl = sym;
198 		}
199 		if (decl == NULL && sym->s_def == DECL)
200 			decl = sym;
201 	}
202 
203 	/* A prototype is better than an old style declaration. */
204 	if (pdecl != NULL)
205 		decl = pdecl;
206 
207 	chkvtui(hte, def, decl);
208 
209 	chkvtdi(hte, def, decl);
210 
211 	chkfaui(hte, def, decl);
212 
213 	chkrvu(hte, def);
214 
215 	chkadecl(hte, def, decl);
216 }
217 
218 /*
219  * Print a warning if the name has been used, but not defined.
220  */
221 static void
222 chkund(hte_t *hte)
223 {
224 	fcall_t	*fcall;
225 	usym_t	*usym;
226 
227 	if (!hte->h_used || hte->h_def)
228 		return;
229 
230 	if ((fcall = hte->h_calls) != NULL) {
231 		/* %s used( %s ), but not defined */
232 		msg(0, hte->h_name, mkpos(&fcall->f_pos));
233 	} else if ((usym = hte->h_usyms) != NULL) {
234 		/* %s used( %s ), but not defined */
235 		msg(0, hte->h_name, mkpos(&usym->u_pos));
236 	}
237 }
238 
239 /*
240  * Print a warning if the name has been defined, but never used.
241  */
242 static void
243 chkdnu(hte_t *hte)
244 {
245 	sym_t	*sym;
246 
247 	if (!hte->h_def || hte->h_used)
248 		return;
249 
250 	for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) {
251 		if (sym->s_def == DEF || sym->s_def == TDEF) {
252 			/* %s defined( %s ), but never used */
253 			msg(1, hte->h_name, mkpos(&sym->s_pos));
254 			break;
255 		}
256 	}
257 }
258 
259 /*
260  * Print a warning if the variable has been declared, but is not used
261  * or defined.
262  */
263 static void
264 chkdnud(hte_t *hte)
265 {
266 	sym_t	*sym;
267 
268 	if (hte->h_syms == NULL || hte->h_used || hte->h_def)
269 		return;
270 
271 	sym = hte->h_syms;
272 	if (TP(sym->s_type)->t_tspec == FUNC)
273 		return;
274 
275 	if (sym->s_def != DECL)
276 		errx(1, "internal error: chkdnud() 1");
277 	/* %s declared( %s ), but never used or defined */
278 	msg(2, hte->h_name, mkpos(&sym->s_pos));
279 }
280 
281 /*
282  * Print a warning if there is more then one definition for
283  * this name.
284  */
285 static void
286 chkmd(hte_t *hte)
287 {
288 	sym_t	*sym, *def1;
289 	char	*pos1;
290 
291 	if (!hte->h_def)
292 		return;
293 
294 	def1 = NULL;
295 	for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) {
296 		/*
297 		 * ANSI C allows tentative definitions of the same name in
298 		 * only one compilation unit.
299 		 */
300 		if (sym->s_def != DEF && (!sflag || sym->s_def != TDEF))
301 			continue;
302 		if (def1 == NULL) {
303 			def1 = sym;
304 			continue;
305 		}
306 		pos1 = xstrdup(mkpos(&def1->s_pos));
307 		/* %s multiply defined\t%s  ::  %s */
308 		msg(3, hte->h_name, pos1, mkpos(&sym->s_pos));
309 		free(pos1);
310 	}
311 }
312 
313 /*
314  * Print a warning if the return value assumed for a function call
315  * differs from the return value of the function definition or
316  * function declaration.
317  *
318  * If no definition/declaration can be found, the assumed return values
319  * are always int. So there is no need to compare with another function
320  * call as it's done for function arguments.
321  */
322 static void
323 chkvtui(hte_t *hte, sym_t *def, sym_t *decl)
324 {
325 	fcall_t	*call;
326 	char	*pos1;
327 	type_t	*tp1, *tp2;
328 	/* LINTED (automatic hides external declaration: warn) */
329 	int	warn, eq;
330 	tspec_t	t1;
331 
332 	if (hte->h_calls == NULL)
333 		return;
334 
335 	if (def == NULL)
336 		def = decl;
337 	if (def == NULL)
338 		return;
339 
340 	t1 = (tp1 = TP(def->s_type)->t_subt)->t_tspec;
341 	for (call = hte->h_calls; call != NULL; call = call->f_nxt) {
342 		tp2 = TP(call->f_type)->t_subt;
343 		eq = eqtype(tp1, tp2, 1, 0, 0, (warn = 0, &warn));
344 		if (!call->f_rused) {
345 			/* no return value used */
346 			if ((t1 == STRUCT || t1 == UNION) && !eq) {
347 				/*
348 				 * If a function returns a struct or union it
349 				 * must be declared to return a struct or
350 				 * union, also if the return value is ignored.
351 				 * This is necessary because the caller must
352 				 * allocate stack space for the return value.
353 				 * If it does not, the return value would over-
354 				 * write other data.
355 				 * XXX Following massage may be confusing
356 				 * because it appears also if the return value
357 				 * was declared inconsistently. But this
358 				 * behaviour matches pcc based lint, so it is
359 				 * accepted for now.
360 				 */
361 				pos1 = xstrdup(mkpos(&def->s_pos));
362 				/* %s value must be decl. before use %s :: %s */
363 				msg(17, hte->h_name,
364 				    pos1, mkpos(&call->f_pos));
365 				free(pos1);
366 			}
367 			continue;
368 		}
369 		if (!eq || (sflag && warn)) {
370 			pos1 = xstrdup(mkpos(&def->s_pos));
371 			/* %s value used inconsistenty\t%s  ::  %s */
372 			msg(4, hte->h_name, pos1, mkpos(&call->f_pos));
373 			free(pos1);
374 		}
375 	}
376 }
377 
378 /*
379  * Print a warning if a definition/declaration does not match another
380  * definition/declaration of the same name. For functions, only the
381  * types of return values are tested.
382  */
383 static void
384 chkvtdi(hte_t *hte, sym_t *def, sym_t *decl)
385 {
386 	sym_t	*sym;
387 	type_t	*tp1, *tp2;
388 	/* LINTED (automatic hides external declaration: warn) */
389 	int	eq, warn;
390 	char	*pos1;
391 
392 	if (def == NULL)
393 		def = decl;
394 	if (def == NULL)
395 		return;
396 
397 	tp1 = TP(def->s_type);
398 	for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) {
399 		if (sym == def)
400 			continue;
401 		tp2 = TP(sym->s_type);
402 		warn = 0;
403 		if (tp1->t_tspec == FUNC && tp2->t_tspec == FUNC) {
404 			eq = eqtype(tp1->t_subt, tp2->t_subt, 1, 0, 0, &warn);
405 		} else {
406 			eq = eqtype(tp1, tp2, 0, 0, 0, &warn);
407 		}
408 		if (!eq || (sflag && warn)) {
409 			pos1 = xstrdup(mkpos(&def->s_pos));
410 			/* %s value declared inconsistently\t%s  ::  %s */
411 			msg(5, hte->h_name, pos1, mkpos(&sym->s_pos));
412 			free(pos1);
413 		}
414 	}
415 }
416 
417 /*
418  * Print a warning if a function is called with arguments which does
419  * not match the function definition, declaration or another call
420  * of the same function.
421  */
422 static void
423 chkfaui(hte_t *hte, sym_t *def, sym_t *decl)
424 {
425 	type_t	*tp1, *tp2, **ap1, **ap2;
426 	pos_t	*pos1p = NULL;
427 	fcall_t	*calls, *call, *call1;
428 	int	n, as;
429 	char	*pos1;
430 	arginf_t *ai;
431 
432 	if ((calls = hte->h_calls) == NULL)
433 		return;
434 
435 	/*
436 	 * If we find a function definition, we use this for comparison,
437 	 * otherwise the first prototype we can find. If there is no
438 	 * definition or prototype declaration, the first function call
439 	 * is used.
440 	 */
441 	tp1 = NULL;
442 	call1 = NULL;
443 	if (def != NULL) {
444 		if ((tp1 = TP(def->s_type))->t_tspec != FUNC)
445 			return;
446 		pos1p = &def->s_pos;
447 	} else if (decl != NULL && TP(decl->s_type)->t_proto) {
448 		if ((tp1 = TP(decl->s_type))->t_tspec != FUNC)
449 			return;
450 		pos1p = &decl->s_pos;
451 	}
452 	if (tp1 == NULL) {
453 		call1 = calls;
454 		calls = calls->f_nxt;
455 		if ((tp1 = TP(call1->f_type))->t_tspec != FUNC)
456 			return;
457 		pos1p = &call1->f_pos;
458 	}
459 
460 	n = 1;
461 	for (call = calls; call != NULL; call = call->f_nxt) {
462 		if ((tp2 = TP(call->f_type))->t_tspec != FUNC)
463 			continue;
464 		ap1 = tp1->t_args;
465 		ap2 = tp2->t_args;
466 		n = 0;
467 		while (*ap1 != NULL && *ap2 != NULL) {
468 			if (def != NULL && def->s_va && n >= def->s_nva)
469 				break;
470 			n++;
471 			chkau(hte, n, def, decl, pos1p, call1, call,
472 			      *ap1, *ap2);
473 			ap1++;
474 			ap2++;
475 		}
476 		if (*ap1 == *ap2) {
477 			/* equal # of arguments */
478 		} else if (def != NULL && def->s_va && n >= def->s_nva) {
479 			/*
480 			 * function definition with VARARGS; The # of
481 			 * arguments of the call must be at least as large
482 			 * as the parameter of VARARGS.
483 			 */
484 		} else if (*ap2 != NULL && tp1->t_proto && tp1->t_vararg) {
485 			/*
486 			 * prototype with ... and function call with
487 			 * at least the same # of arguments as declared
488 			 * in the prototype.
489 			 */
490 		} else {
491 			pos1 = xstrdup(mkpos(pos1p));
492 			/* %s: variable # of args\t%s  ::  %s */
493 			msg(7, hte->h_name, pos1, mkpos(&call->f_pos));
494 			free(pos1);
495 			continue;
496 		}
497 
498 		/* perform SCANFLIKE/PRINTFLIKE tests */
499 		if (def == NULL || (!def->s_prfl && !def->s_scfl))
500 			continue;
501 		as = def->s_prfl ? def->s_nprfl : def->s_nscfl;
502 		for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) {
503 			if (ai->a_num == as)
504 				break;
505 		}
506 		if (ai == NULL || !ai->a_fmt)
507 			continue;
508 		if (def->s_prfl) {
509 			printflike(hte, call, n, ai->a_fstrg, ap2);
510 		} else {
511 			scanflike(hte, call, n, ai->a_fstrg, ap2);
512 		}
513 	}
514 }
515 
516 /*
517  * Check a single argument in a function call.
518  *
519  *  hte		a pointer to the hash table entry of the function
520  *  n		the number of the argument (1..)
521  *  def		the function definition or NULL
522  *  decl	prototype declaration, old style declaration or NULL
523  *  pos1p	position of definition, declaration of first call
524  *  call1	first call, if both def and decl are old style def/decl
525  *  call	checked call
526  *  arg1	currently checked argument of def/decl/call1
527  *  arg2	currently checked argument of call
528  *
529  */
530 static void
531 chkau(hte_t *hte, int n, sym_t *def, sym_t *decl, pos_t *pos1p,
532 	fcall_t *call1, fcall_t *call, type_t *arg1, type_t *arg2)
533 {
534 	/* LINTED (automatic hides external declaration: warn) */
535 	int	promote, asgn, warn;
536 	tspec_t	t1, t2;
537 	arginf_t *ai, *ai1;
538 	char	*pos1;
539 
540 	/*
541 	 * If a function definition is available (def != NULL), we compair the
542 	 * function call (call) with the definition. Otherwise, if a function
543 	 * definition is available and it is not an old style definition
544 	 * (decl != NULL && TP(decl->s_type)->t_proto), we compair the call
545 	 * with this declaration. Otherwise we compair it with the first
546 	 * call we have found (call1).
547 	 */
548 
549 	/* arg1 must be promoted if it stems from an old style definition */
550 	promote = def != NULL && def->s_osdef;
551 
552 	/*
553 	 * If we compair with a definition or declaration, we must perform
554 	 * the same checks for qualifiers in indirected types as in
555 	 * assignments.
556 	 */
557 	asgn = def != NULL || (decl != NULL && TP(decl->s_type)->t_proto);
558 
559 	warn = 0;
560 	if (eqtype(arg1, arg2, 1, promote, asgn, &warn) && (!sflag || !warn))
561 		return;
562 
563 	/*
564 	 * Other lint implementations print warnings as soon as the type
565 	 * of an argument does not match exactly the expected type. The
566 	 * result are lots of warnings which are really not necessary.
567 	 * We print a warning only if
568 	 *   (0) at least one type is not an interger type and types differ
569 	 *   (1) hflag is set and types differ
570 	 *   (2) types differ, except in signedness
571 	 * If the argument is an integer constant whose msb is not set,
572 	 * signedness is ignored (e.g. 0 matches both signed and unsigned
573 	 * int). This is with and without hflag.
574 	 * If the argument is an integer constant with value 0 and the
575 	 * expected argument is of type pointer and the width of the
576 	 * interger constant is the same as the width of the pointer,
577 	 * no warning is printed.
578 	 */
579 	t1 = arg1->t_tspec;
580 	t2 = arg2->t_tspec;
581 	if (isityp(t1) && isityp(t2) && !arg1->t_isenum && !arg2->t_isenum) {
582 		if (promote) {
583 			/*
584 			 * XXX Here is a problem: Althrough it is possible to
585 			 * pass an int where a char/short it expected, there
586 			 * may be loss in significant digits. We should first
587 			 * check for const arguments if they can be converted
588 			 * into the original parameter type.
589 			 */
590 			if (t1 == FLOAT) {
591 				t1 = DOUBLE;
592 			} else if (t1 == CHAR || t1 == SCHAR) {
593 				t1 = INT;
594 			} else if (t1 == UCHAR) {
595 				t1 = tflag ? UINT : INT;
596 			} else if (t1 == SHORT) {
597 				t1 = INT;
598 			} else if (t1 == USHORT) {
599 				/* CONSTCOND */
600 				t1 = INT_MAX < USHRT_MAX || tflag ? UINT : INT;
601 			}
602 		}
603 
604 		if (styp(t1) == styp(t2)) {
605 
606 			/*
607 			 * types differ only in signedness; get information
608 			 * about arguments
609 			 */
610 
611 			/*
612 			 * treat a definition like a call with variable
613 			 * arguments
614 			 */
615 			ai1 = call1 != NULL ? call1->f_args : NULL;
616 
617 			/*
618 			 * if two calls are compared, ai1 is set to the
619 			 * information for the n-th argument, if this was
620 			 * a constant, otherwise to NULL
621 			 */
622 			for ( ; ai1 != NULL; ai1 = ai1->a_nxt) {
623 				if (ai1->a_num == n)
624 					break;
625 			}
626 			/*
627 			 * ai is set to the information of the n-th arg
628 			 * of the (second) call, if this was a constant,
629 			 * otherwise to NULL
630 			 */
631 			for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) {
632 				if (ai->a_num == n)
633 					break;
634 			}
635 
636 			if (ai1 == NULL && ai == NULL) {
637 				/* no constant at all */
638 				if (!hflag)
639 					return;
640 			} else if (ai1 == NULL || ai == NULL) {
641 				/* one constant */
642 				if (ai == NULL)
643 					ai = ai1;
644 				if (ai->a_zero || ai->a_pcon)
645 					/* same value in signed and unsigned */
646 					return;
647 				/* value (not representation) differently */
648 			} else {
649 				/*
650 				 * two constants, one signed, one unsigned;
651 				 * if the msb of one of the constants is set,
652 				 * the argument is used inconsistently.
653 				 */
654 				if (!ai1->a_ncon && !ai->a_ncon)
655 					return;
656 			}
657 		}
658 
659 	} else if (t1 == PTR && isityp(t2)) {
660 		for (ai = call->f_args; ai != NULL; ai = ai->a_nxt) {
661 			if (ai->a_num == n)
662 				break;
663 		}
664 		/*
665 		 * Vendor implementations of lint (e.g. HP-UX, Digital UNIX)
666 		 * don't care about the size of the integer argument,
667 		 * only whether or not it is zero.  We do the same.
668 		 */
669 		if (ai != NULL && ai->a_zero)
670 			return;
671 	}
672 
673 	pos1 = xstrdup(mkpos(pos1p));
674 	/* %s, arg %d used inconsistently\t%s  ::  %s */
675 	msg(6, hte->h_name, n, pos1, mkpos(&call->f_pos));
676 	free(pos1);
677 }
678 
679 /*
680  * Compare the types in the NULL-terminated array ap with the format
681  * string fmt.
682  */
683 static void
684 printflike(hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap)
685 {
686 	const	char *fp;
687 	int	fc;
688 	int	fwidth, prec, left, sign, space, alt, zero;
689 	tspec_t	sz, t1, t2 = NOTSPEC;
690 	type_t	*tp;
691 
692 	fp = fmt;
693 	fc = *fp++;
694 
695 	for ( ; ; ) {
696 		if (fc == '\0') {
697 			if (*ap != NULL)
698 				tomanyarg(hte, call);
699 			break;
700 		}
701 		if (fc != '%') {
702 			badfmt(hte, call);
703 			break;
704 		}
705 		fc = *fp++;
706 		fwidth = prec = left = sign = space = alt = zero = 0;
707 		sz = NOTSPEC;
708 
709 		/* Flags */
710 		for ( ; ; ) {
711 			if (fc == '-') {
712 				if (left)
713 					break;
714 				left = 1;
715 			} else if (fc == '+') {
716 				if (sign)
717 					break;
718 				sign = 1;
719 			} else if (fc == ' ') {
720 				if (space)
721 					break;
722 				space = 1;
723 			} else if (fc == '#') {
724 				if (alt)
725 					break;
726 				alt = 1;
727 			} else if (fc == '0') {
728 				if (zero)
729 					break;
730 				zero = 1;
731 			} else {
732 				break;
733 			}
734 			fc = *fp++;
735 		}
736 
737 		/* field width */
738 		if (isdigit(fc)) {
739 			fwidth = 1;
740 			do { fc = *fp++; } while (isdigit(fc)) ;
741 		} else if (fc == '*') {
742 			fwidth = 1;
743 			fc = *fp++;
744 			if ((tp = *ap++) == NULL) {
745 				tofewarg(hte, call);
746 				break;
747 			}
748 			n++;
749 			if ((t1 = tp->t_tspec) != INT && (hflag || t1 != UINT))
750 				inconarg(hte, call, n);
751 		}
752 
753 		/* precision */
754 		if (fc == '.') {
755 			fc = *fp++;
756 			prec = 1;
757 			if (isdigit(fc)) {
758 				do { fc = *fp++; } while (isdigit(fc));
759 			} else if (fc == '*') {
760 				fc = *fp++;
761 				if ((tp = *ap++) == NULL) {
762 					tofewarg(hte, call);
763 					break;
764 				}
765 				n++;
766 				if (tp->t_tspec != INT)
767 					inconarg(hte, call, n);
768 			} else {
769 				badfmt(hte, call);
770 				break;
771 			}
772 		}
773 
774 		if (fc == 'h') {
775 			sz = SHORT;
776 		} else if (fc == 'l') {
777 			sz = LONG;
778 		} else if (fc == 'q') {
779 			sz = QUAD;
780 		} else if (fc == 'L') {
781 			sz = LDOUBLE;
782 		}
783 		if (sz != NOTSPEC)
784 			fc = *fp++;
785 
786 		if (fc == '%') {
787 			if (sz != NOTSPEC || left || sign || space ||
788 			    alt || zero || prec || fwidth) {
789 				badfmt(hte, call);
790 			}
791 			fc = *fp++;
792 			continue;
793 		}
794 
795 		if (fc == '\0') {
796 			badfmt(hte, call);
797 			break;
798 		}
799 
800 		if ((tp = *ap++) == NULL) {
801 			tofewarg(hte, call);
802 			break;
803 		}
804 		n++;
805 		if ((t1 = tp->t_tspec) == PTR)
806 			t2 = tp->t_subt->t_tspec;
807 
808 		if (fc == 'd' || fc == 'i') {
809 			if (alt || sz == LDOUBLE) {
810 				badfmt(hte, call);
811 				break;
812 			}
813 		int_conv:
814 			if (sz == LONG) {
815 				if (t1 != LONG && (hflag || t1 != ULONG))
816 					inconarg(hte, call, n);
817 			} else if (sz == QUAD) {
818 				if (t1 != QUAD && (hflag || t1 != UQUAD))
819 					inconarg(hte, call, n);
820 			} else {
821 				/*
822 				 * SHORT is always promoted to INT, USHORT
823 				 * to INT or UINT.
824 				 */
825 				if (t1 != INT && (hflag || t1 != UINT))
826 					inconarg(hte, call, n);
827 			}
828 		} else if (fc == 'o' || fc == 'u' || fc == 'x' || fc == 'X') {
829 			if ((alt && fc == 'u') || sz == LDOUBLE)
830 				badfmt(hte, call);
831 		uint_conv:
832 			if (sz == LONG) {
833 				if (t1 != ULONG && (hflag || t1 != LONG))
834 					inconarg(hte, call, n);
835 			} else if (sz == QUAD) {
836 				if (t1 != UQUAD && (hflag || t1 != QUAD))
837 					inconarg(hte, call, n);
838 			} else if (sz == SHORT) {
839 				/* USHORT was promoted to INT or UINT */
840 				if (t1 != UINT && t1 != INT)
841 					inconarg(hte, call, n);
842 			} else {
843 				if (t1 != UINT && (hflag || t1 != INT))
844 					inconarg(hte, call, n);
845 			}
846 		} else if (fc == 'D' || fc == 'O' || fc == 'U') {
847 			if ((alt && fc != 'O') || sz != NOTSPEC || !tflag)
848 				badfmt(hte, call);
849 			sz = LONG;
850 			if (fc == 'D') {
851 				goto int_conv;
852 			} else {
853 				goto uint_conv;
854 			}
855 		} else if (fc == 'f' || fc == 'e' || fc == 'E' ||
856 			   fc == 'g' || fc == 'G') {
857 			if (sz == NOTSPEC)
858 				sz = DOUBLE;
859 			if (sz != DOUBLE && sz != LDOUBLE)
860 				badfmt(hte, call);
861 			if (t1 != sz)
862 				inconarg(hte, call, n);
863 		} else if (fc == 'c') {
864 			if (sz != NOTSPEC || alt || zero)
865 				badfmt(hte, call);
866 			if (t1 != INT)
867 				inconarg(hte, call, n);
868 		} else if (fc == 's') {
869 			if (sz != NOTSPEC || alt || zero)
870 				badfmt(hte, call);
871 			if (t1 != PTR ||
872 			    (t2 != CHAR && t2 != UCHAR && t2 != SCHAR)) {
873 				inconarg(hte, call, n);
874 			}
875 		} else if (fc == 'p') {
876 			if (fwidth || prec || sz != NOTSPEC || alt || zero)
877 				badfmt(hte, call);
878 			if (t1 != PTR || (hflag && t2 != VOID))
879 				inconarg(hte, call, n);
880 		} else if (fc == 'n') {
881 			if (fwidth || prec || alt || zero || sz == LDOUBLE)
882 				badfmt(hte, call);
883 			if (t1 != PTR) {
884 				inconarg(hte, call, n);
885 			} else if (sz == LONG) {
886 				if (t2 != LONG && t2 != ULONG)
887 					inconarg(hte, call, n);
888 			} else if (sz == SHORT) {
889 				if (t2 != SHORT && t2 != USHORT)
890 					inconarg(hte, call, n);
891 			} else {
892 				if (t2 != INT && t2 != UINT)
893 					inconarg(hte, call, n);
894 			}
895 		} else {
896 			badfmt(hte, call);
897 			break;
898 		}
899 
900 		fc = *fp++;
901 	}
902 }
903 
904 /*
905  * Compare the types in the NULL-terminated array ap with the format
906  * string fmt.
907  */
908 static void
909 scanflike(hte_t *hte, fcall_t *call, int n, const char *fmt, type_t **ap)
910 {
911 	const	char *fp;
912 	int	fc;
913 	int	noasgn, fwidth;
914 	tspec_t	sz, t1 = NOTSPEC, t2 = NOTSPEC;
915 	type_t	*tp = NULL;
916 
917 	fp = fmt;
918 	fc = *fp++;
919 
920 	for ( ; ; ) {
921 		if (fc == '\0') {
922 			if (*ap != NULL)
923 				tomanyarg(hte, call);
924 			break;
925 		}
926 		if (fc != '%') {
927 			badfmt(hte, call);
928 			break;
929 		}
930 		fc = *fp++;
931 
932 		noasgn = fwidth = 0;
933 		sz = NOTSPEC;
934 
935 		if (fc == '*') {
936 			noasgn = 1;
937 			fc = *fp++;
938 		}
939 
940 		if (isdigit(fc)) {
941 			fwidth = 1;
942 			do { fc = *fp++; } while (isdigit(fc));
943 		}
944 
945 		if (fc == 'h') {
946 			sz = SHORT;
947 		} else if (fc == 'l') {
948 			sz = LONG;
949 		} else if (fc == 'q') {
950 			sz = QUAD;
951 		} else if (fc == 'L') {
952 			sz = LDOUBLE;
953 		}
954 		if (sz != NOTSPEC)
955 			fc = *fp++;
956 
957 		if (fc == '%') {
958 			if (sz != NOTSPEC || noasgn || fwidth)
959 				badfmt(hte, call);
960 			fc = *fp++;
961 			continue;
962 		}
963 
964 		if (!noasgn) {
965 			if ((tp = *ap++) == NULL) {
966 				tofewarg(hte, call);
967 				break;
968 			}
969 			n++;
970 			if ((t1 = tp->t_tspec) == PTR)
971 				t2 = tp->t_subt->t_tspec;
972 		}
973 
974 		if (fc == 'd' || fc == 'i' || fc == 'n') {
975 			if (sz == LDOUBLE)
976 				badfmt(hte, call);
977 			if (sz != SHORT && sz != LONG && sz != QUAD)
978 				sz = INT;
979 		conv:
980 			if (!noasgn) {
981 				if (t1 != PTR) {
982 					inconarg(hte, call, n);
983 				} else if (t2 != styp(sz)) {
984 					inconarg(hte, call, n);
985 				} else if (hflag && t2 != sz) {
986 					inconarg(hte, call, n);
987 				} else if (tp->t_subt->t_const) {
988 					inconarg(hte, call, n);
989 				}
990 			}
991 		} else if (fc == 'o' || fc == 'u' || fc == 'x') {
992 			if (sz == LDOUBLE)
993 				badfmt(hte, call);
994 			if (sz == SHORT) {
995 				sz = USHORT;
996 			} else if (sz == LONG) {
997 				sz = ULONG;
998 			} else if (sz == QUAD) {
999 				sz = UQUAD;
1000 			} else {
1001 				sz = UINT;
1002 			}
1003 			goto conv;
1004 		} else if (fc == 'D') {
1005 			if (sz != NOTSPEC || !tflag)
1006 				badfmt(hte, call);
1007 			sz = LONG;
1008 			goto conv;
1009 		} else if (fc == 'O') {
1010 			if (sz != NOTSPEC || !tflag)
1011 				badfmt(hte, call);
1012 			sz = ULONG;
1013 			goto conv;
1014 		} else if (fc == 'X') {
1015 			/*
1016 			 * XXX valid in ANSI C, but in NetBSD's libc imple-
1017 			 * mented as "lx". Thats why it should be avoided.
1018 			 */
1019 			if (sz != NOTSPEC || !tflag)
1020 				badfmt(hte, call);
1021 			sz = ULONG;
1022 			goto conv;
1023 		} else if (fc == 'E') {
1024 			/*
1025 			 * XXX valid in ANSI C, but in NetBSD's libc imple-
1026 			 * mented as "lf". Thats why it should be avoided.
1027 			 */
1028 			if (sz != NOTSPEC || !tflag)
1029 				badfmt(hte, call);
1030 			sz = DOUBLE;
1031 			goto conv;
1032 		} else if (fc == 'F') {
1033 			/* XXX only for backward compatibility */
1034 			if (sz != NOTSPEC || !tflag)
1035 				badfmt(hte, call);
1036 			sz = DOUBLE;
1037 			goto conv;
1038 		} else if (fc == 'G') {
1039 			/*
1040 			 * XXX valid in ANSI C, but in NetBSD's libc not
1041 			 * implemented
1042 			 */
1043 			if (sz != NOTSPEC && sz != LONG && sz != LDOUBLE)
1044 				badfmt(hte, call);
1045 			goto fconv;
1046 		} else if (fc == 'e' || fc == 'f' || fc == 'g') {
1047 		fconv:
1048 			if (sz == NOTSPEC) {
1049 				sz = FLOAT;
1050 			} else if (sz == LONG) {
1051 				sz = DOUBLE;
1052 			} else if (sz != LDOUBLE) {
1053 				badfmt(hte, call);
1054 				sz = FLOAT;
1055 			}
1056 			goto conv;
1057 		} else if (fc == 's' || fc == '[' || fc == 'c') {
1058 			if (sz != NOTSPEC)
1059 				badfmt(hte, call);
1060 			if (fc == '[') {
1061 				if ((fc = *fp++) == '-') {
1062 					badfmt(hte, call);
1063 					fc = *fp++;
1064 				}
1065 				if (fc != ']') {
1066 					badfmt(hte, call);
1067 					if (fc == '\0')
1068 						break;
1069 				}
1070 			}
1071 			if (!noasgn) {
1072 				if (t1 != PTR) {
1073 					inconarg(hte, call, n);
1074 				} else if (t2 != CHAR && t2 != UCHAR &&
1075 					   t2 != SCHAR) {
1076 					inconarg(hte, call, n);
1077 				}
1078 			}
1079 		} else if (fc == 'p') {
1080 			if (sz != NOTSPEC)
1081 				badfmt(hte, call);
1082 			if (!noasgn) {
1083 				if (t1 != PTR || t2 != PTR) {
1084 					inconarg(hte, call, n);
1085 				} else if (tp->t_subt->t_subt->t_tspec!=VOID) {
1086 					if (hflag)
1087 						inconarg(hte, call, n);
1088 				}
1089 			}
1090 		} else {
1091 			badfmt(hte, call);
1092 			break;
1093 		}
1094 
1095 		fc = *fp++;
1096 	}
1097 }
1098 
1099 static void
1100 badfmt(hte_t *hte, fcall_t *call)
1101 {
1102 
1103 	/* %s: malformed format string\t%s */
1104 	msg(13, hte->h_name, mkpos(&call->f_pos));
1105 }
1106 
1107 static void
1108 inconarg(hte_t *hte, fcall_t *call, int n)
1109 {
1110 
1111 	/* %s, arg %d inconsistent with format\t%s(%d) */
1112 	msg(14, hte->h_name, n, mkpos(&call->f_pos));
1113 }
1114 
1115 static void
1116 tofewarg(hte_t *hte, fcall_t *call)
1117 {
1118 
1119 	/* %s: too few args for format  \t%s */
1120 	msg(15, hte->h_name, mkpos(&call->f_pos));
1121 }
1122 
1123 static void
1124 tomanyarg(hte_t *hte, fcall_t *call)
1125 {
1126 
1127 	/* %s: too many args for format  \t%s */
1128 	msg(16, hte->h_name, mkpos(&call->f_pos));
1129 }
1130 
1131 
1132 /*
1133  * Print warnings for return values which are used, but not returned,
1134  * or return values which are always or sometimes ignored.
1135  */
1136 static void
1137 chkrvu(hte_t *hte, sym_t *def)
1138 {
1139 	fcall_t	*call;
1140 	int	used, ignored;
1141 
1142 	if (def == NULL)
1143 		/* don't know wheter or not the functions returns a value */
1144 		return;
1145 
1146 	if (hte->h_calls == NULL)
1147 		return;
1148 
1149 	if (def->s_rval) {
1150 		/* function has return value */
1151 		used = ignored = 0;
1152 		for (call = hte->h_calls; call != NULL; call = call->f_nxt) {
1153 			used |= call->f_rused || call->f_rdisc;
1154 			ignored |= !call->f_rused && !call->f_rdisc;
1155 		}
1156 		/*
1157 		 * XXX as soon as we are able to disable single warnings
1158 		 * the following dependencies from hflag should be removed.
1159 		 * but for now I do'nt want to be botherd by this warnings
1160 		 * which are almost always useless.
1161 		 */
1162 		if (!used && ignored) {
1163 			if (hflag)
1164 				/* %s returns value which is always ignored */
1165 				msg(8, hte->h_name);
1166 		} else if (used && ignored) {
1167 			if (hflag)
1168 				/* %s returns value which is sometimes ign. */
1169 				msg(9, hte->h_name);
1170 		}
1171 	} else {
1172 		/* function has no return value */
1173 		for (call = hte->h_calls; call != NULL; call = call->f_nxt) {
1174 			if (call->f_rused)
1175 				/* %s value is used( %s ), but none ret. */
1176 				msg(10, hte->h_name, mkpos(&call->f_pos));
1177 		}
1178 	}
1179 }
1180 
1181 /*
1182  * Print warnings for inconsistent argument declarations.
1183  */
1184 static void
1185 chkadecl(hte_t *hte, sym_t *def, sym_t *decl)
1186 {
1187 	/* LINTED (automatic hides external declaration: warn) */
1188 	int	osdef, eq, warn, n;
1189 	sym_t	*sym1, *sym;
1190 	type_t	**ap1, **ap2, *tp1, *tp2;
1191 	char	*pos1;
1192 	const	char *pos2;
1193 
1194 	osdef = 0;
1195 	if (def != NULL) {
1196 		osdef = def->s_osdef;
1197 		sym1 = def;
1198 	} else if (decl != NULL && TP(decl->s_type)->t_proto) {
1199 		sym1 = decl;
1200 	} else {
1201 		return;
1202 	}
1203 	if (TP(sym1->s_type)->t_tspec != FUNC)
1204 		return;
1205 
1206 	/*
1207 	 * XXX Prototypes should also be compared with old style function
1208 	 * declarations.
1209 	 */
1210 
1211 	for (sym = hte->h_syms; sym != NULL; sym = sym->s_nxt) {
1212 		if (sym == sym1 || !TP(sym->s_type)->t_proto)
1213 			continue;
1214 		ap1 = TP(sym1->s_type)->t_args;
1215 		ap2 = TP(sym->s_type)->t_args;
1216 		n = 0;
1217 		while (*ap1 != NULL && *ap2 != NULL) {
1218 			warn = 0;
1219 			eq = eqtype(*ap1, *ap2, 1, osdef, 0, &warn);
1220 			if (!eq || warn) {
1221 				pos1 = xstrdup(mkpos(&sym1->s_pos));
1222 				pos2 = mkpos(&sym->s_pos);
1223 				/* %s, arg %d declared inconsistently ... */
1224 				msg(11, hte->h_name, n + 1, pos1, pos2);
1225 				free(pos1);
1226 			}
1227 			n++;
1228 			ap1++;
1229 			ap2++;
1230 		}
1231 		if (*ap1 == *ap2) {
1232 			tp1 = TP(sym1->s_type);
1233 			tp2 = TP(sym->s_type);
1234 			if (tp1->t_vararg == tp2->t_vararg)
1235 				continue;
1236 			if (tp2->t_vararg &&
1237 			    sym1->s_va && sym1->s_nva == n && !sflag) {
1238 				continue;
1239 			}
1240 		}
1241 		/* %s: variable # of args declared\t%s  ::  %s */
1242 		pos1 = xstrdup(mkpos(&sym1->s_pos));
1243 		msg(12, hte->h_name, pos1, mkpos(&sym->s_pos));
1244 		free(pos1);
1245 	}
1246 }
1247 
1248 
1249 /*
1250  * Check compatibility of two types. Returns 1 if types are compatible,
1251  * otherwise 0.
1252  *
1253  * ignqual	if set, ignore qualifiers of outhermost type; used for
1254  *		function arguments
1255  * promote	if set, promote left type before comparison; used for
1256  *		comparisons of arguments with parameters of old style
1257  *		definitions
1258  * asgn		left indirected type must have at least the same qualifiers
1259  *		like right indirected type (for assignments and function
1260  *		arguments)
1261  * *warn	set to 1 if an old style declaration was compared with
1262  *		an incompatible prototype declaration
1263  */
1264 static int
1265 eqtype(type_t *tp1, type_t *tp2, int ignqual, int promot, int asgn, int *warn)
1266 {
1267 	tspec_t	t, to;
1268 	int	indir;
1269 
1270 	to = NOTSPEC;
1271 	indir = 0;
1272 
1273 	while (tp1 != NULL && tp2 != NULL) {
1274 
1275 		t = tp1->t_tspec;
1276 		if (promot) {
1277 			if (t == FLOAT) {
1278 				t = DOUBLE;
1279 			} else if (t == CHAR || t == SCHAR) {
1280 				t = INT;
1281 			} else if (t == UCHAR) {
1282 				t = tflag ? UINT : INT;
1283 			} else if (t == SHORT) {
1284 				t = INT;
1285 			} else if (t == USHORT) {
1286 				/* CONSTCOND */
1287 				t = INT_MAX < USHRT_MAX || tflag ? UINT : INT;
1288 			}
1289 		}
1290 
1291 		if (asgn && to == PTR) {
1292 			if (indir == 1 && (t == VOID || tp2->t_tspec == VOID))
1293 				return (1);
1294 		}
1295 
1296 		if (t != tp2->t_tspec) {
1297 			/*
1298 			 * Give pointer to types which differ only in
1299 			 * signedness a chance if not sflag and not hflag.
1300 			 */
1301 			if (sflag || hflag || to != PTR)
1302 				return (0);
1303 			if (styp(t) != styp(tp2->t_tspec))
1304 				return (0);
1305 		}
1306 
1307 		if (tp1->t_isenum && tp2->t_isenum) {
1308 			if (tp1->t_istag && tp2->t_istag) {
1309 				return (tp1->t_tag == tp2->t_tag);
1310 			} else if (tp1->t_istynam && tp2->t_istynam) {
1311 				return (tp1->t_tynam == tp2->t_tynam);
1312 			} else if (tp1->t_isuniqpos && tp2->t_isuniqpos) {
1313 				return (tp1->t_uniqpos.p_line ==
1314 				      tp2->t_uniqpos.p_line &&
1315 				    tp1->t_uniqpos.p_file ==
1316 				      tp2->t_uniqpos.p_file &&
1317 				    tp1->t_uniqpos.p_uniq ==
1318 				      tp2->t_uniqpos.p_uniq);
1319 			} else {
1320 				return (0);
1321 			}
1322 		}
1323 
1324 		/*
1325 		 * XXX Handle combinations of enum and int if eflag is set.
1326 		 * But note: enum and 0 should be allowed.
1327 		 */
1328 
1329 		if (asgn && indir == 1) {
1330 			if (!tp1->t_const && tp2->t_const)
1331 				return (0);
1332 			if (!tp1->t_volatile && tp2->t_volatile)
1333 				return (0);
1334 		} else if (!ignqual && !tflag) {
1335 			if (tp1->t_const != tp2->t_const)
1336 				return (0);
1337 			if (tp1->t_const != tp2->t_const)
1338 				return (0);
1339 		}
1340 
1341 		if (t == STRUCT || t == UNION) {
1342 			if (tp1->t_istag && tp2->t_istag) {
1343 				return (tp1->t_tag == tp2->t_tag);
1344 			} else if (tp1->t_istynam && tp2->t_istynam) {
1345 				return (tp1->t_tynam == tp2->t_tynam);
1346 			} else if (tp1->t_isuniqpos && tp2->t_isuniqpos) {
1347 				return (tp1->t_uniqpos.p_line ==
1348 				      tp2->t_uniqpos.p_line &&
1349 				    tp1->t_uniqpos.p_file ==
1350 				      tp2->t_uniqpos.p_file &&
1351 				    tp1->t_uniqpos.p_uniq ==
1352 				      tp2->t_uniqpos.p_uniq);
1353 			} else {
1354 				return (0);
1355 			}
1356 		}
1357 
1358 		if (t == ARRAY && tp1->t_dim != tp2->t_dim) {
1359 			if (tp1->t_dim != 0 && tp2->t_dim != 0)
1360 				return (0);
1361 		}
1362 
1363 		if (t == FUNC) {
1364 			if (tp1->t_proto && tp2->t_proto) {
1365 				if (!eqargs(tp1, tp2, warn))
1366 					return (0);
1367 			} else if (tp1->t_proto) {
1368 				if (!mnoarg(tp1, warn))
1369 					return (0);
1370 			} else if (tp2->t_proto) {
1371 				if (!mnoarg(tp2, warn))
1372 					return (0);
1373 			}
1374 		}
1375 
1376 		tp1 = tp1->t_subt;
1377 		tp2 = tp2->t_subt;
1378 		ignqual = promot = 0;
1379 		to = t;
1380 		indir++;
1381 
1382 	}
1383 
1384 	return (tp1 == tp2);
1385 }
1386 
1387 /*
1388  * Compares arguments of two prototypes
1389  */
1390 static int
1391 eqargs(type_t *tp1, type_t *tp2, int *warn)
1392 {
1393 	type_t	**a1, **a2;
1394 
1395 	if (tp1->t_vararg != tp2->t_vararg)
1396 		return (0);
1397 
1398 	a1 = tp1->t_args;
1399 	a2 = tp2->t_args;
1400 
1401 	while (*a1 != NULL && *a2 != NULL) {
1402 
1403 		if (eqtype(*a1, *a2, 1, 0, 0, warn) == 0)
1404 			return (0);
1405 
1406 		a1++;
1407 		a2++;
1408 
1409 	}
1410 
1411 	return (*a1 == *a2);
1412 }
1413 
1414 /*
1415  * mnoarg() (matches functions with no argument type information)
1416  * returns 1 if all parameters of a prototype are compatible with
1417  * and old style function declaration.
1418  * This is the case if following conditions are met:
1419  *	1. the prototype must have a fixed number of parameters
1420  *	2. no parameter is of type float
1421  *	3. no parameter is converted to another type if integer promotion
1422  *	   is applied on it
1423  */
1424 static int
1425 mnoarg(type_t *tp, int *warn)
1426 {
1427 	type_t	**arg;
1428 	tspec_t	t;
1429 
1430 	if (tp->t_vararg && warn != NULL)
1431 		*warn = 1;
1432 	for (arg = tp->t_args; *arg != NULL; arg++) {
1433 		if ((t = (*arg)->t_tspec) == FLOAT)
1434 			return (0);
1435 		if (t == CHAR || t == SCHAR || t == UCHAR)
1436 			return (0);
1437 		if (t == SHORT || t == USHORT)
1438 			return (0);
1439 	}
1440 	return (1);
1441 }
1442