xref: /netbsd-src/usr.bin/xlint/lint1/decl.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /* $NetBSD: decl.c,v 1.38 2006/11/08 18:31:15 christos 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 #if HAVE_NBTOOL_CONFIG_H
36 #include "nbtool_config.h"
37 #endif
38 
39 #include <sys/cdefs.h>
40 #if defined(__RCSID) && !defined(lint)
41 __RCSID("$NetBSD: decl.c,v 1.38 2006/11/08 18:31:15 christos Exp $");
42 #endif
43 
44 #include <sys/param.h>
45 #include <limits.h>
46 #include <stdlib.h>
47 #include <string.h>
48 
49 #include "lint1.h"
50 
51 const	char *unnamed = "<unnamed>";
52 
53 /* shared type structures for arithmtic types and void */
54 static	type_t	*typetab;
55 
56 /* value of next enumerator during declaration of enum types */
57 int	enumval;
58 
59 /*
60  * pointer to top element of a stack which contains informations local
61  * to nested declarations
62  */
63 dinfo_t	*dcs;
64 
65 static	type_t	*tdeferr(type_t *, tspec_t);
66 static	void	settdsym(type_t *, sym_t *);
67 static	tspec_t	mrgtspec(tspec_t, tspec_t);
68 static	void	align(int, int);
69 static	sym_t	*newtag(sym_t *, scl_t, int, int);
70 static	int	eqargs(type_t *, type_t *, int *);
71 static	int	mnoarg(type_t *, int *);
72 static	int	chkosdef(sym_t *, sym_t *);
73 static	int	chkptdecl(sym_t *, sym_t *);
74 static	sym_t	*nsfunc(sym_t *, sym_t *);
75 static	void	osfunc(sym_t *, sym_t *);
76 static	void	ledecl(sym_t *);
77 static	int	chkinit(sym_t *);
78 static	void	chkausg(int, sym_t *);
79 static	void	chkvusg(int, sym_t *);
80 static	void	chklusg(sym_t *);
81 static	void	chktusg(sym_t *);
82 static	void	chkglvar(sym_t *);
83 static	void	glchksz(sym_t *);
84 
85 /*
86  * initializes all global vars used in declarations
87  */
88 void
89 initdecl(void)
90 {
91 	int i;
92 
93 	/* declaration stack */
94 	dcs = xcalloc(1, sizeof (dinfo_t));
95 	dcs->d_ctx = EXTERN;
96 	dcs->d_ldlsym = &dcs->d_dlsyms;
97 
98 	/* type information and classification */
99 	inittyp();
100 
101 	/* shared type structures */
102 	typetab = xcalloc(NTSPEC, sizeof (type_t));
103 	for (i = 0; i < NTSPEC; i++)
104 		typetab[i].t_tspec = NOTSPEC;
105 	typetab[BOOL].t_tspec = BOOL;
106 	typetab[CHAR].t_tspec = CHAR;
107 	typetab[SCHAR].t_tspec = SCHAR;
108 	typetab[UCHAR].t_tspec = UCHAR;
109 	typetab[SHORT].t_tspec = SHORT;
110 	typetab[USHORT].t_tspec = USHORT;
111 	typetab[INT].t_tspec = INT;
112 	typetab[UINT].t_tspec = UINT;
113 	typetab[LONG].t_tspec = LONG;
114 	typetab[ULONG].t_tspec = ULONG;
115 	typetab[QUAD].t_tspec = QUAD;
116 	typetab[UQUAD].t_tspec = UQUAD;
117 	typetab[FLOAT].t_tspec = FLOAT;
118 	typetab[DOUBLE].t_tspec = DOUBLE;
119 	typetab[LDOUBLE].t_tspec = LDOUBLE;
120 	typetab[VOID].t_tspec = VOID;
121 	/*
122 	 * Next two are not real types. They are only used by the parser
123 	 * to return keywords "signed" and "unsigned"
124 	 */
125 	typetab[SIGNED].t_tspec = SIGNED;
126 	typetab[UNSIGN].t_tspec = UNSIGN;
127 }
128 
129 /*
130  * Returns a shared type structure vor arithmetic types and void.
131  *
132  * It's important do duplicate this structure (using duptyp() or tdupdyp())
133  * if it is to be modified (adding qualifiers or anything else).
134  */
135 type_t *
136 gettyp(tspec_t t)
137 {
138 
139 	return (&typetab[t]);
140 }
141 
142 type_t *
143 duptyp(const type_t *tp)
144 {
145 	type_t	*ntp;
146 
147 	ntp = getblk(sizeof (type_t));
148 	STRUCT_ASSIGN(*ntp, *tp);
149 	return (ntp);
150 }
151 
152 /*
153  * Use tduptyp() instead of duptyp() inside expressions (if the
154  * allocated memory should be freed after the expr).
155  */
156 type_t *
157 tduptyp(const type_t *tp)
158 {
159 	type_t	*ntp;
160 
161 	ntp = tgetblk(sizeof (type_t));
162 	STRUCT_ASSIGN(*ntp, *tp);
163 	return (ntp);
164 }
165 
166 /*
167  * Returns 1 if the argument is void or an incomplete array,
168  * struct, union or enum type.
169  */
170 int
171 incompl(type_t *tp)
172 {
173 	tspec_t	t;
174 
175 	if ((t = tp->t_tspec) == VOID) {
176 		return (1);
177 	} else if (t == ARRAY) {
178 		return (tp->t_aincompl);
179 	} else if (t == STRUCT || t == UNION) {
180 		return (tp->t_str->sincompl);
181 	} else if (t == ENUM) {
182 		return (tp->t_enum->eincompl);
183 	}
184 	return (0);
185 }
186 
187 /*
188  * Set the flag for (in)complete array, struct, union or enum
189  * types.
190  */
191 void
192 setcompl(type_t *tp, int ic)
193 {
194 	tspec_t	t;
195 
196 	if ((t = tp->t_tspec) == ARRAY) {
197 		tp->t_aincompl = ic;
198 	} else if (t == STRUCT || t == UNION) {
199 		tp->t_str->sincompl = ic;
200 	} else {
201 		if (t != ENUM)
202 			LERROR("setcompl()");
203 		tp->t_enum->eincompl = ic;
204 	}
205 }
206 
207 /*
208  * Remember the storage class of the current declaration in dcs->d_scl
209  * (the top element of the declaration stack) and detect multiple
210  * storage classes.
211  */
212 void
213 addscl(scl_t sc)
214 {
215 
216 	if (sc == INLINE) {
217 		if (dcs->d_inline)
218 			/* duplicate '%s' */
219 			warning(10, "inline");
220 		dcs->d_inline = 1;
221 		return;
222 	}
223 	if (dcs->d_type != NULL || dcs->d_atyp != NOTSPEC ||
224 	    dcs->d_smod != NOTSPEC || dcs->d_lmod != NOTSPEC) {
225 		/* storage class after type is obsolescent */
226 		warning(83);
227 	}
228 	if (dcs->d_scl == NOSCL) {
229 		dcs->d_scl = sc;
230 	} else {
231 		/*
232 		 * multiple storage classes. An error will be reported in
233 		 * deftyp().
234 		 */
235 		dcs->d_mscl = 1;
236 	}
237 }
238 
239 /*
240  * Remember the type, modifier or typedef name returned by the parser
241  * in *dcs (top element of decl stack). This information is used in
242  * deftyp() to build the type used for all declarators in this
243  * declaration.
244  *
245  * Is tp->t_typedef 1, the type comes from a previously defined typename.
246  * Otherwise it comes from a type specifier (int, long, ...) or a
247  * struct/union/enum tag.
248  */
249 void
250 addtype(type_t *tp)
251 {
252 	tspec_t	t;
253 
254 	if (tp->t_typedef) {
255 		if (dcs->d_type != NULL || dcs->d_atyp != NOTSPEC ||
256 		    dcs->d_lmod != NOTSPEC || dcs->d_smod != NOTSPEC) {
257 			/*
258 			 * something like "typedef int a; int a b;"
259 			 * This should not happen with current grammar.
260 			 */
261 			LERROR("addtype()");
262 		}
263 		dcs->d_type = tp;
264 		return;
265 	}
266 
267 	t = tp->t_tspec;
268 
269 	if (t == STRUCT || t == UNION || t == ENUM) {
270 		/*
271 		 * something like "int struct a ..."
272 		 * struct/union/enum with anything else is not allowed
273 		 */
274 		if (dcs->d_type != NULL || dcs->d_atyp != NOTSPEC ||
275 		    dcs->d_lmod != NOTSPEC || dcs->d_smod != NOTSPEC) {
276 			/*
277 			 * remember that an error must be reported in
278 			 * deftyp().
279 			 */
280 			dcs->d_terr = 1;
281 			dcs->d_atyp = dcs->d_lmod = dcs->d_smod = NOTSPEC;
282 		}
283 		dcs->d_type = tp;
284 		return;
285 	}
286 
287 	if (dcs->d_type != NULL && !dcs->d_type->t_typedef) {
288 		/*
289 		 * something like "struct a int"
290 		 * struct/union/enum with anything else is not allowed
291 		 */
292 		dcs->d_terr = 1;
293 		return;
294 	}
295 
296 	if (t == LONG && dcs->d_lmod == LONG) {
297 		/* "long long" or "long ... long" */
298 		t = QUAD;
299 		dcs->d_lmod = NOTSPEC;
300 		if (!quadflg)
301 			/* %s C does not support 'long long' */
302 			(void)c99ism(265, tflag ? "traditional" : "c89");
303 	}
304 
305 	if (dcs->d_type != NULL && dcs->d_type->t_typedef) {
306 		/* something like "typedef int a; a long ..." */
307 		dcs->d_type = tdeferr(dcs->d_type, t);
308 		return;
309 	}
310 
311 	/* now it can be only a combination of arithmetic types and void */
312 	if (t == SIGNED || t == UNSIGN) {
313 		/* remeber specifiers "signed" and "unsigned" in dcs->d_smod */
314 		if (dcs->d_smod != NOTSPEC)
315 			/*
316 			 * more than one "signed" and/or "unsigned"; print
317 			 * an error in deftyp()
318 			 */
319 			dcs->d_terr = 1;
320 		dcs->d_smod = t;
321 	} else if (t == SHORT || t == LONG || t == QUAD) {
322 		/*
323 		 * remember specifiers "short", "long" and "long long" in
324 		 * dcs->d_lmod
325 		 */
326 		if (dcs->d_lmod != NOTSPEC)
327 			/* more than one, print error in deftyp() */
328 			dcs->d_terr = 1;
329 		dcs->d_lmod = t;
330 	} else {
331 		/*
332 		 * remember specifiers "void", "char", "int", "float" or
333 		 * "double" int dcs->d_atyp
334 		 */
335 		if (dcs->d_atyp != NOTSPEC)
336 			/* more than one, print error in deftyp() */
337 			dcs->d_terr = 1;
338 		dcs->d_atyp = t;
339 	}
340 }
341 
342 /*
343  * called if a list of declaration specifiers contains a typedef name
344  * and other specifiers (except struct, union, enum, typedef name)
345  */
346 static type_t *
347 tdeferr(type_t *td, tspec_t t)
348 {
349 	tspec_t	t2;
350 
351 	t2 = td->t_tspec;
352 
353 	switch (t) {
354 	case SIGNED:
355 	case UNSIGN:
356 		if (t2 == CHAR || t2 == SHORT || t2 == INT || t2 == LONG ||
357 		    t2 == QUAD) {
358 			if (!tflag)
359 				/* modifying typedef with ... */
360 				warning(5, ttab[t].tt_name);
361 			td = duptyp(gettyp(mrgtspec(t2, t)));
362 			td->t_typedef = 1;
363 			return (td);
364 		}
365 		break;
366 	case SHORT:
367 		if (t2 == INT || t2 == UINT) {
368 			/* modifying typedef with ... */
369 			warning(5, "short");
370 			td = duptyp(gettyp(t2 == INT ? SHORT : USHORT));
371 			td->t_typedef = 1;
372 			return (td);
373 		}
374 		break;
375 	case LONG:
376 		if (t2 == INT || t2 == UINT || t2 == LONG || t2 == ULONG ||
377 		    t2 == FLOAT || t2 == DOUBLE) {
378 			/* modifying typedef with ... */
379 			warning(5, "long");
380 			if (t2 == INT) {
381 				td = gettyp(LONG);
382 			} else if (t2 == UINT) {
383 				td = gettyp(ULONG);
384 			} else if (t2 == LONG) {
385 				td = gettyp(QUAD);
386 			} else if (t2 == ULONG) {
387 				td = gettyp(UQUAD);
388 			} else if (t2 == FLOAT) {
389 				td = gettyp(DOUBLE);
390 			} else if (t2 == DOUBLE) {
391 				td = gettyp(LDOUBLE);
392 			}
393 			td = duptyp(td);
394 			td->t_typedef = 1;
395 			return (td);
396 		}
397 		break;
398 		/* LINTED (enumeration values not handled in switch) */
399 	case NOTSPEC:
400 	case USHORT:
401 	case UCHAR:
402 	case SCHAR:
403 	case CHAR:
404 	case BOOL:
405 	case FUNC:
406 	case ARRAY:
407 	case PTR:
408 	case ENUM:
409 	case UNION:
410 	case STRUCT:
411 	case VOID:
412 	case LDOUBLE:
413 	case DOUBLE:
414 	case FLOAT:
415 	case UQUAD:
416 	case QUAD:
417 	case ULONG:
418 	case UINT:
419 	case INT:
420 		break;
421 
422 	case NTSPEC:	/* this value unused */
423 		break;
424 	}
425 
426 	/* Anything other is not accepted. */
427 
428 	dcs->d_terr = 1;
429 	return (td);
430 }
431 
432 /*
433  * Remember the symbol of a typedef name (2nd arg) in a struct, union
434  * or enum tag if the typedef name is the first defined for this tag.
435  *
436  * If the tag is unnamed, the typdef name is used for identification
437  * of this tag in lint2. Although its possible that more than one typedef
438  * name is defined for one tag, the first name defined should be unique
439  * if the tag is unnamed.
440  */
441 static void
442 settdsym(type_t *tp, sym_t *sym)
443 {
444 	tspec_t	t;
445 
446 	if ((t = tp->t_tspec) == STRUCT || t == UNION) {
447 		if (tp->t_str->stdef == NULL)
448 			tp->t_str->stdef = sym;
449 	} else if (t == ENUM) {
450 		if (tp->t_enum->etdef == NULL)
451 			tp->t_enum->etdef = sym;
452 	}
453 }
454 
455 /*
456  * Remember a qualifier which is part of the declaration specifiers
457  * (and not the declarator) in the top element of the declaration stack.
458  * Also detect multiple qualifiers of the same kind.
459 
460  * The remembered qualifier is used by deftyp() to construct the type
461  * for all declarators.
462  */
463 void
464 addqual(tqual_t q)
465 {
466 
467 	if (q == CONST) {
468 		if (dcs->d_const) {
469 			/* duplicate "%s" */
470 			warning(10, "const");
471 		}
472 		dcs->d_const = 1;
473 	} else {
474 		if (q != VOLATILE)
475 			LERROR("addqual()");
476 		if (dcs->d_volatile) {
477 			/* duplicate "%s" */
478 			warning(10, "volatile");
479 		}
480 		dcs->d_volatile = 1;
481 	}
482 }
483 
484 /*
485  * Go to the next declaration level (structs, nested structs, blocks,
486  * argument declaration lists ...)
487  */
488 void
489 pushdecl(scl_t sc)
490 {
491 	dinfo_t	*di;
492 
493 	if (dflag)
494 		(void)printf("pushdecl(%d)\n", (int)sc);
495 
496 	/* put a new element on the declaration stack */
497 	di = xcalloc(1, sizeof (dinfo_t));
498 	di->d_nxt = dcs;
499 	dcs = di;
500 	di->d_ctx = sc;
501 	di->d_ldlsym = &di->d_dlsyms;
502 }
503 
504 /*
505  * Go back to previous declaration level
506  */
507 void
508 popdecl(void)
509 {
510 	dinfo_t	*di;
511 
512 	if (dflag)
513 		(void)printf("popdecl(%d)\n", (int)dcs->d_ctx);
514 
515 	if (dcs->d_nxt == NULL)
516 		LERROR("popdecl()");
517 	di = dcs;
518 	dcs = di->d_nxt;
519 	switch (di->d_ctx) {
520 	case EXTERN:
521 		/* there is nothing after external declarations */
522 		LERROR("popdecl()");
523 		/* NOTREACHED */
524 	case MOS:
525 	case MOU:
526 	case ENUMCON:
527 		/*
528 		 * Symbols declared in (nested) structs or enums are
529 		 * part of the next level (they are removed from the
530 		 * symbol table if the symbols of the outher level are
531 		 * removed)
532 		 */
533 		if ((*dcs->d_ldlsym = di->d_dlsyms) != NULL)
534 			dcs->d_ldlsym = di->d_ldlsym;
535 		break;
536 	case ARG:
537 		/*
538 		 * All symbols in dcs->d_dlsyms are introduced in old style
539 		 * argument declarations (it's not clean, but possible).
540 		 * They are appended to the list of symbols declared in
541 		 * an old style argument identifier list or a new style
542 		 * parameter type list.
543 		 */
544 		if (di->d_dlsyms != NULL) {
545 			*di->d_ldlsym = dcs->d_fpsyms;
546 			dcs->d_fpsyms = di->d_dlsyms;
547 		}
548 		break;
549 	case ABSTRACT:
550 		/*
551 		 * casts and sizeof
552 		 * Append all symbols declared in the abstract declaration
553 		 * to the list of symbols declared in the surounding decl.
554 		 * or block.
555 		 * XXX I'm not sure whether they should be removed from the
556 		 * symbol table now or later.
557 		 */
558 		if ((*dcs->d_ldlsym = di->d_dlsyms) != NULL)
559 			dcs->d_ldlsym = di->d_ldlsym;
560 		break;
561 	case AUTO:
562 		/* check usage of local vars */
563 		chkusage(di);
564 		/* FALLTHROUGH */
565 	case PARG:
566 		/* usage of arguments will be checked by funcend() */
567 		rmsyms(di->d_dlsyms);
568 		break;
569 	default:
570 		LERROR("popdecl()");
571 	}
572 	free(di);
573 }
574 
575 /*
576  * Set flag d_asm in all declaration stack elements up to the
577  * outermost one.
578  *
579  * This is used to mark compound statements which have, possibly in
580  * nested compound statements, asm statements. For these compound
581  * statements no warnings about unused or unitialized variables are
582  * printed.
583  *
584  * There is no need to clear d_asm in dinfo structs with context AUTO,
585  * because these structs are freed at the end of the compound statement.
586  * But it must be cleard in the outermost dinfo struct, which has
587  * context EXTERN. This could be done in clrtyp() and would work for
588  * C, but not for C++ (due to mixed statements and declarations). Thus
589  * we clear it in glclup(), which is used to do some cleanup after
590  * global declarations/definitions.
591  */
592 void
593 setasm(void)
594 {
595 	dinfo_t	*di;
596 
597 	for (di = dcs; di != NULL; di = di->d_nxt)
598 		di->d_asm = 1;
599 }
600 
601 /*
602  * Clean all elements of the top element of declaration stack which
603  * will be used by the next declaration
604  */
605 void
606 clrtyp(void)
607 {
608 
609 	dcs->d_atyp = dcs->d_smod = dcs->d_lmod = NOTSPEC;
610 	dcs->d_scl = NOSCL;
611 	dcs->d_type = NULL;
612 	dcs->d_const = dcs->d_volatile = 0;
613 	dcs->d_inline = 0;
614 	dcs->d_mscl = dcs->d_terr = 0;
615 	dcs->d_nedecl = 0;
616 	dcs->d_notyp = 0;
617 }
618 
619 /*
620  * Create a type structure from the informations gathered in
621  * the declaration stack.
622  * Complain about storage classes which are not possible in current
623  * context.
624  */
625 void
626 deftyp(void)
627 {
628 	tspec_t	t, s, l;
629 	type_t	*tp;
630 	scl_t	scl;
631 
632 	t = dcs->d_atyp;	/* BOOL, CHAR, INT, FLOAT, DOUBLE, VOID */
633 	s = dcs->d_smod;	/* SIGNED, UNSIGNED */
634 	l = dcs->d_lmod;	/* SHORT, LONG, QUAD */
635 	tp = dcs->d_type;
636 	scl = dcs->d_scl;
637 
638 	if (t == NOTSPEC && s == NOTSPEC && l == NOTSPEC && tp == NULL)
639 		dcs->d_notyp = 1;
640 
641 	if (tp != NULL && (t != NOTSPEC || s != NOTSPEC || l != NOTSPEC)) {
642 		/* should never happen */
643 		LERROR("deftyp()");
644 	}
645 
646 	if (tp == NULL) {
647 		switch (t) {
648 		case BOOL:
649 			break;
650 		case NOTSPEC:
651 			t = INT;
652 			/* FALLTHROUGH */
653 		case INT:
654 			if (s == NOTSPEC)
655 				s = SIGNED;
656 			break;
657 		case CHAR:
658 			if (l != NOTSPEC) {
659 				dcs->d_terr = 1;
660 				l = NOTSPEC;
661 			}
662 			break;
663 		case FLOAT:
664 			if (l == LONG) {
665 				l = NOTSPEC;
666 				t = DOUBLE;
667 				if (!tflag)
668 					/* use 'double' instead of ...  */
669 					warning(6);
670 			}
671 			break;
672 		case DOUBLE:
673 			if (l == LONG) {
674 				l = NOTSPEC;
675 				t = LDOUBLE;
676 				if (tflag)
677 					/* 'long double' is illegal in ... */
678 					warning(266);
679 			}
680 			break;
681 		case VOID:
682 			break;
683 		default:
684 			LERROR("deftyp()");
685 		}
686 		if (t != INT && t != CHAR && (s != NOTSPEC || l != NOTSPEC)) {
687 			dcs->d_terr = 1;
688 			l = s = NOTSPEC;
689 		}
690 		if (l != NOTSPEC)
691 			t = l;
692 		dcs->d_type = gettyp(mrgtspec(t, s));
693 	}
694 
695 	if (dcs->d_mscl) {
696 		/* only one storage class allowed */
697 		error(7);
698 	}
699 	if (dcs->d_terr) {
700 		/* illegal type combination */
701 		error(4);
702 	}
703 
704 	if (dcs->d_ctx == EXTERN) {
705 		if (scl == REG || scl == AUTO) {
706 			/* illegal storage class */
707 			error(8);
708 			scl = NOSCL;
709 		}
710 	} else if (dcs->d_ctx == ARG || dcs->d_ctx == PARG) {
711 		if (scl != NOSCL && scl != REG) {
712 			/* only "register" valid ... */
713 			error(9);
714 			scl = NOSCL;
715 		}
716 	}
717 
718 	dcs->d_scl = scl;
719 
720 	if (dcs->d_const && dcs->d_type->t_const) {
721 		if (!dcs->d_type->t_typedef)
722 			LERROR("deftyp()");
723 		/* typedef already qualified with "%s" */
724 		warning(68, "const");
725 	}
726 	if (dcs->d_volatile && dcs->d_type->t_volatile) {
727 		if (!dcs->d_type->t_typedef)
728 			LERROR("deftyp()");
729 		/* typedef already qualified with "%s" */
730 		warning(68, "volatile");
731 	}
732 
733 	if (dcs->d_const || dcs->d_volatile) {
734 		dcs->d_type = duptyp(dcs->d_type);
735 		dcs->d_type->t_const |= dcs->d_const;
736 		dcs->d_type->t_volatile |= dcs->d_volatile;
737 	}
738 }
739 
740 /*
741  * Merge type specifiers (char, ..., long long, signed, unsigned).
742  */
743 static tspec_t
744 mrgtspec(tspec_t t, tspec_t s)
745 {
746 
747 	if (s == SIGNED || s == UNSIGN) {
748 		if (t == CHAR) {
749 			t = s == SIGNED ? SCHAR : UCHAR;
750 		} else if (t == SHORT) {
751 			t = s == SIGNED ? SHORT : USHORT;
752 		} else if (t == INT) {
753 			t = s == SIGNED ? INT : UINT;
754 		} else if (t == LONG) {
755 			t = s == SIGNED ? LONG : ULONG;
756 		} else if (t == QUAD) {
757 			t = s == SIGNED ? QUAD : UQUAD;
758 		}
759 	}
760 
761 	return (t);
762 }
763 
764 /*
765  * Return the length of a type in bit.
766  *
767  * Printing a message if the outhermost dimension of an array is 0 must
768  * be done by the caller. All other problems are reported by length()
769  * if name is not NULL.
770  */
771 int
772 length(type_t *tp, const char *name)
773 {
774 	int	elem, elsz;
775 
776 	elem = 1;
777 	while (tp && tp->t_tspec == ARRAY) {
778 		elem *= tp->t_dim;
779 		tp = tp->t_subt;
780 	}
781 	if (tp == NULL)
782 		return -1;
783 
784 	switch (tp->t_tspec) {
785 	case FUNC:
786 		/* compiler takes size of function */
787 		LERROR(msgs[12]);
788 		/* NOTREACHED */
789 	case STRUCT:
790 	case UNION:
791 		if (incompl(tp) && name != NULL) {
792 			/* incomplete structure or union %s: %s */
793 			error(31, tp->t_str->stag->s_name, name);
794 		}
795 		elsz = tp->t_str->size;
796 		break;
797 	case ENUM:
798 		if (incompl(tp) && name != NULL) {
799 			/* incomplete enum type: %s */
800 			warning(13, name);
801 		}
802 		/* FALLTHROUGH */
803 	default:
804 		elsz = size(tp->t_tspec);
805 		if (elsz <= 0)
806 			LERROR("length()");
807 		break;
808 	}
809 	return (elem * elsz);
810 }
811 
812 /*
813  * Get the alignment of the given Type in bits.
814  */
815 int
816 getbound(type_t *tp)
817 {
818 	int	a;
819 	tspec_t	t;
820 
821 	while (tp && tp->t_tspec == ARRAY)
822 		tp = tp->t_subt;
823 
824 	if (tp == NULL)
825 		return -1;
826 
827 	if ((t = tp->t_tspec) == STRUCT || t == UNION) {
828 		a = tp->t_str->align;
829 	} else if (t == FUNC) {
830 		/* compiler takes alignment of function */
831 		error(14);
832 		a = ALIGN(1) * CHAR_BIT;
833 	} else {
834 		if ((a = size(t)) == 0) {
835 			a = CHAR_BIT;
836 		} else if (a > ALIGN(1) * CHAR_BIT) {
837 			a = ALIGN(1) * CHAR_BIT;
838 		}
839 	}
840 	if (a < CHAR_BIT || a > ALIGN(1) * CHAR_BIT)
841 		LERROR("getbound()");
842 	return (a);
843 }
844 
845 /*
846  * Concatenate two lists of symbols by s_nxt. Used by declarations of
847  * struct/union/enum elements and parameters.
848  */
849 sym_t *
850 lnklst(sym_t *l1, sym_t *l2)
851 {
852 	sym_t	*l;
853 
854 	if ((l = l1) == NULL)
855 		return (l2);
856 	while (l1->s_nxt != NULL)
857 		l1 = l1->s_nxt;
858 	l1->s_nxt = l2;
859 	return (l);
860 }
861 
862 /*
863  * Check if the type of the given symbol is valid and print an error
864  * message if it is not.
865  *
866  * Invalid types are:
867  * - arrays of incomlete types or functions
868  * - functions returning arrays or functions
869  * - void types other than type of function or pointer
870  */
871 void
872 chktyp(sym_t *sym)
873 {
874 	tspec_t	to, t;
875 	type_t	**tpp, *tp;
876 
877 	tpp = &sym->s_type;
878 	to = NOTSPEC;
879 	while ((tp = *tpp) != NULL) {
880 		t = tp->t_tspec;
881 		/*
882 		 * If this is the type of an old style function definition,
883 		 * a better warning is printed in funcdef().
884 		 */
885 		if (t == FUNC && !tp->t_proto &&
886 		    !(to == NOTSPEC && sym->s_osdef)) {
887 			if (sflag && hflag)
888 				/* function declaration is not a prototype */
889 				warning(287);
890 		}
891 		if (to == FUNC) {
892 			if (t == FUNC || t == ARRAY) {
893 				/* function returns illegal type */
894 				error(15);
895 				if (t == FUNC) {
896 					*tpp = incref(*tpp, PTR);
897 				} else {
898 					*tpp = incref((*tpp)->t_subt, PTR);
899 				}
900 				return;
901 			} else if (tp->t_const || tp->t_volatile) {
902 				if (sflag) {	/* XXX oder better !tflag ? */
903 					/* function cannot return const... */
904 					warning(228);
905 				}
906 			}
907 		} if (to == ARRAY) {
908 			if (t == FUNC) {
909 				/* array of function is illegal */
910 				error(16);
911 				*tpp = gettyp(INT);
912 				return;
913 			} else if (t == ARRAY && tp->t_dim == 0) {
914 				/* null dimension */
915 				error(17);
916 				return;
917 			} else if (t == VOID) {
918 				/* illegal use of void */
919 				error(18);
920 				*tpp = gettyp(INT);
921 #if 0	/* errors are produced by length() */
922 			} else if (incompl(tp)) {
923 				/* array of incomplete type */
924 				if (sflag) {
925 					error(301);
926 				} else {
927 					warning(301);
928 				}
929 #endif
930 			}
931 		} else if (to == NOTSPEC && t == VOID) {
932 			if (dcs->d_ctx == PARG) {
933 				if (sym->s_scl != ABSTRACT) {
934 					if (sym->s_name == unnamed)
935 						LERROR("chktyp()");
936 					/* void param cannot have name: %s */
937 					error(61, sym->s_name);
938 					*tpp = gettyp(INT);
939 				}
940 			} else if (dcs->d_ctx == ABSTRACT) {
941 				/* ok */
942 			} else if (sym->s_scl != TYPEDEF) {
943 				/* void type for %s */
944 				error(19, sym->s_name);
945 				*tpp = gettyp(INT);
946 			}
947 		}
948 		if (t == VOID && to != PTR) {
949 			if (tp->t_const || tp->t_volatile) {
950 				/* inappropriate qualifiers with "void" */
951 				warning(69);
952 				tp->t_const = tp->t_volatile = 0;
953 			}
954 		}
955 		tpp = &tp->t_subt;
956 		to = t;
957 	}
958 }
959 
960 /*
961  * Process the declarator of a struct/union element.
962  */
963 sym_t *
964 decl1str(sym_t *dsym)
965 {
966 	type_t	*tp;
967 	tspec_t	t;
968 	int	sz, len;
969 	int	o = 0;	/* Appease gcc */
970 	scl_t	sc;
971 
972 	if ((sc = dsym->s_scl) != MOS && sc != MOU)
973 		LERROR("decl1str()");
974 
975 	if (dcs->d_rdcsym != NULL) {
976 		if ((sc = dcs->d_rdcsym->s_scl) != MOS && sc != MOU)
977 			/* should be ensured by storesym() */
978 			LERROR("decl1str()");
979 		if (dsym->s_styp == dcs->d_rdcsym->s_styp) {
980 			/* duplicate member name: %s */
981 			error(33, dsym->s_name);
982 			rmsym(dcs->d_rdcsym);
983 		}
984 	}
985 
986 	chktyp(dsym);
987 
988 	t = (tp = dsym->s_type)->t_tspec;
989 
990 	if (dsym->s_field) {
991 		/*
992 		 * bit field
993 		 *
994 		 * only unsigned und signed int are protable bit-field types
995 		 *(at least in ANSI C, in traditional C only unsigned int)
996 		 */
997 		if (t == CHAR || t == UCHAR || t == SCHAR ||
998 		    t == SHORT || t == USHORT || t == ENUM) {
999 			if (bitfieldtype_ok == 0) {
1000 				if (sflag) {
1001 					char buf[64];
1002 					/*
1003 					 * bit-field type '%s' invalid in
1004 					 * ANSI C
1005 					 */
1006 					warning(273,
1007 					    tyname(buf, sizeof(buf), tp));
1008 				} else if (pflag) {
1009 					/* nonportable bit-field type */
1010 					warning(34);
1011 				}
1012 			}
1013 		} else if (t == INT && dcs->d_smod == NOTSPEC) {
1014 			if (pflag && bitfieldtype_ok == 0) {
1015 				/* nonportable bit-field type */
1016 				warning(34);
1017 			}
1018 		} else if (t != INT && t != UINT) {
1019 			/*
1020 			 * Non-integer types are always illegal for
1021 			 * bitfields, regardless of BITFIELDTYPE.
1022 			 * Integer types not dealt with above are
1023 			 * okay only if BITFIELDTYPE is in effect.
1024 			 */
1025 			if (bitfieldtype_ok == 0 || isityp(t) == 0) {
1026 				/* illegal bit-field type */
1027 				error(35);
1028 				sz = tp->t_flen;
1029 				dsym->s_type = tp = duptyp(gettyp(t = INT));
1030 				if ((tp->t_flen = sz) > size(t))
1031 					tp->t_flen = size(t);
1032 			}
1033 		}
1034 		if ((len = tp->t_flen) < 0 || len > size(t)) {
1035 			/* illegal bit-field size */
1036 			error(36);
1037 			tp->t_flen = size(t);
1038 		} else if (len == 0 && dsym->s_name != unnamed) {
1039 			/* zero size bit-field */
1040 			error(37);
1041 			tp->t_flen = size(t);
1042 		}
1043 		if (dsym->s_scl == MOU) {
1044 			/* illegal use of bit-field */
1045 			error(41);
1046 			dsym->s_type->t_isfield = 0;
1047 			dsym->s_field = 0;
1048 		}
1049 	} else if (t == FUNC) {
1050 		/* function illegal in structure or union */
1051 		error(38);
1052 		dsym->s_type = tp = incref(tp, t = PTR);
1053 	}
1054 
1055 	/*
1056 	 * bit-fields of length 0 are not warned about because length()
1057 	 * does not return the length of the bit-field but the length
1058 	 * of the type the bit-field is packed in (its ok)
1059 	 */
1060 	if ((sz = length(dsym->s_type, dsym->s_name)) == 0) {
1061 		if (t == ARRAY && dsym->s_type->t_dim == 0) {
1062 			/* illegal zero sized structure member: %s */
1063 			c99ism(39, dsym->s_name);
1064 		}
1065 	}
1066 
1067 	if (dcs->d_ctx == MOU) {
1068 		o = dcs->d_offset;
1069 		dcs->d_offset = 0;
1070 	}
1071 	if (dsym->s_field) {
1072 		align(getbound(tp), tp->t_flen);
1073 		dsym->s_value.v_quad = (dcs->d_offset / size(t)) * size(t);
1074 		tp->t_foffs = dcs->d_offset - (int)dsym->s_value.v_quad;
1075 		dcs->d_offset += tp->t_flen;
1076 	} else {
1077 		align(getbound(tp), 0);
1078 		dsym->s_value.v_quad = dcs->d_offset;
1079 		dcs->d_offset += sz;
1080 	}
1081 	if (dcs->d_ctx == MOU) {
1082 		if (o > dcs->d_offset)
1083 			dcs->d_offset = o;
1084 	}
1085 
1086 	chkfdef(dsym, 0);
1087 
1088 	/*
1089 	 * Clear the BITFIELDTYPE indicator after processing each
1090 	 * structure element.
1091 	 */
1092 	bitfieldtype_ok = 0;
1093 
1094 	return (dsym);
1095 }
1096 
1097 /*
1098  * Aligns next structure element as required.
1099  *
1100  * al contains the required alignment, len the length of a bit-field.
1101  */
1102 static void
1103 align(int al, int len)
1104 {
1105 	int	no;
1106 
1107 	/*
1108 	 * The alignment of the current element becomes the alignment of
1109 	 * the struct/union if it is larger than the current alignment
1110 	 * of the struct/union.
1111 	 */
1112 	if (al > dcs->d_stralign)
1113 		dcs->d_stralign = al;
1114 
1115 	no = (dcs->d_offset + (al - 1)) & ~(al - 1);
1116 	if (len == 0 || dcs->d_offset + len > no)
1117 		dcs->d_offset = no;
1118 }
1119 
1120 /*
1121  * Remember the width of the field in its type structure.
1122  */
1123 sym_t *
1124 bitfield(sym_t *dsym, int len)
1125 {
1126 
1127 	if (dsym == NULL) {
1128 		dsym = getblk(sizeof (sym_t));
1129 		dsym->s_name = unnamed;
1130 		dsym->s_kind = FMOS;
1131 		dsym->s_scl = MOS;
1132 		dsym->s_type = gettyp(UINT);
1133 		dsym->s_blklev = -1;
1134 	}
1135 	dsym->s_type = duptyp(dsym->s_type);
1136 	dsym->s_type->t_isfield = 1;
1137 	dsym->s_type->t_flen = len;
1138 	dsym->s_field = 1;
1139 	return (dsym);
1140 }
1141 
1142 /*
1143  * Collect informations about a sequence of asterisks and qualifiers
1144  * in a list of type pqinf_t.
1145  * Qualifiers refer always to the left asterisk. The rightmost asterisk
1146  * will be at the top of the list.
1147  */
1148 pqinf_t *
1149 mergepq(pqinf_t *p1, pqinf_t *p2)
1150 {
1151 	pqinf_t	*p;
1152 
1153 	if (p2->p_pcnt != 0) {
1154 		/* left '*' at the end of the list */
1155 		for (p = p2; p->p_nxt != NULL; p = p->p_nxt)
1156 			continue;
1157 		p->p_nxt = p1;
1158 		return (p2);
1159 	} else {
1160 		if (p2->p_const) {
1161 			if (p1->p_const) {
1162 				/* duplicate %s */
1163 				warning(10, "const");
1164 			}
1165 			p1->p_const = 1;
1166 		}
1167 		if (p2->p_volatile) {
1168 			if (p1->p_volatile) {
1169 				/* duplicate %s */
1170 				warning(10, "volatile");
1171 			}
1172 			p1->p_volatile = 1;
1173 		}
1174 		free(p2);
1175 		return (p1);
1176 	}
1177 }
1178 
1179 /*
1180  * Followint 3 functions extend the type of a declarator with
1181  * pointer, function and array types.
1182  *
1183  * The current type is the Type built by deftyp() (dcs->d_type) and
1184  * pointer, function and array types already added for this
1185  * declarator. The new type extension is inserted between both.
1186  */
1187 sym_t *
1188 addptr(sym_t *decl, pqinf_t *pi)
1189 {
1190 	type_t	**tpp, *tp;
1191 	pqinf_t	*npi;
1192 
1193 	tpp = &decl->s_type;
1194 	while (*tpp && *tpp != dcs->d_type)
1195 		tpp = &(*tpp)->t_subt;
1196 	if (*tpp == NULL)
1197 		return decl;
1198 
1199 	while (pi != NULL) {
1200 		*tpp = tp = getblk(sizeof (type_t));
1201 		tp->t_tspec = PTR;
1202 		tp->t_const = pi->p_const;
1203 		tp->t_volatile = pi->p_volatile;
1204 		*(tpp = &tp->t_subt) = dcs->d_type;
1205 		npi = pi->p_nxt;
1206 		free(pi);
1207 		pi = npi;
1208 	}
1209 	return (decl);
1210 }
1211 
1212 /*
1213  * If a dimension was specified, dim is 1, otherwise 0
1214  * n is the specified dimension
1215  */
1216 sym_t *
1217 addarray(sym_t *decl, int dim, int n)
1218 {
1219 	type_t	**tpp, *tp;
1220 
1221 	tpp = &decl->s_type;
1222 	while (*tpp && *tpp != dcs->d_type)
1223 		tpp = &(*tpp)->t_subt;
1224 	if (*tpp == NULL)
1225 	    return decl;
1226 
1227 	*tpp = tp = getblk(sizeof (type_t));
1228 	tp->t_tspec = ARRAY;
1229 	tp->t_subt = dcs->d_type;
1230 	tp->t_dim = n;
1231 
1232 	if (n < 0) {
1233 		/* negative array dimension */
1234 		error(20, n);
1235 		n = 0;
1236 	} else if (n == 0 && dim) {
1237 		/* zero array dimension */
1238 		c99ism(322, dim);
1239 	} else if (n == 0 && !dim) {
1240 		/* is incomplete type */
1241 		setcompl(tp, 1);
1242 	}
1243 
1244 	return (decl);
1245 }
1246 
1247 sym_t *
1248 addfunc(sym_t *decl, sym_t *args)
1249 {
1250 	type_t	**tpp, *tp;
1251 
1252 	if (dcs->d_proto) {
1253 		if (tflag)
1254 			/* function prototypes are illegal in traditional C */
1255 			warning(270);
1256 		args = nsfunc(decl, args);
1257 	} else {
1258 		osfunc(decl, args);
1259 	}
1260 
1261 	/*
1262 	 * The symbols are removed from the symbol table by popdecl() after
1263 	 * addfunc(). To be able to restore them if this is a function
1264 	 * definition, a pointer to the list of all symbols is stored in
1265 	 * dcs->d_nxt->d_fpsyms. Also a list of the arguments (concatenated
1266 	 * by s_nxt) is stored in dcs->d_nxt->d_fargs.
1267 	 * (dcs->d_nxt must be used because *dcs is the declaration stack
1268 	 * element created for the list of params and is removed after
1269 	 * addfunc())
1270 	 */
1271 	if (dcs->d_nxt->d_ctx == EXTERN &&
1272 	    decl->s_type == dcs->d_nxt->d_type) {
1273 		dcs->d_nxt->d_fpsyms = dcs->d_dlsyms;
1274 		dcs->d_nxt->d_fargs = args;
1275 	}
1276 
1277 	tpp = &decl->s_type;
1278 	while (*tpp && *tpp != dcs->d_nxt->d_type)
1279 		tpp = &(*tpp)->t_subt;
1280 	if (*tpp == NULL)
1281 	    return decl;
1282 
1283 	*tpp = tp = getblk(sizeof (type_t));
1284 	tp->t_tspec = FUNC;
1285 	tp->t_subt = dcs->d_nxt->d_type;
1286 	if ((tp->t_proto = dcs->d_proto) != 0)
1287 		tp->t_args = args;
1288 	tp->t_vararg = dcs->d_vararg;
1289 
1290 	return (decl);
1291 }
1292 
1293 /*
1294  * Called for new style function declarations.
1295  */
1296 /* ARGSUSED */
1297 static sym_t *
1298 nsfunc(sym_t *decl, sym_t *args)
1299 {
1300 	sym_t	*arg, *sym;
1301 	scl_t	sc;
1302 	int	n;
1303 
1304 	/*
1305 	 * Declarations of structs/unions/enums in param lists are legal,
1306 	 * but senseless.
1307 	 */
1308 	for (sym = dcs->d_dlsyms; sym != NULL; sym = sym->s_dlnxt) {
1309 		sc = sym->s_scl;
1310 		if (sc == STRTAG || sc == UNIONTAG || sc == ENUMTAG) {
1311 			/* dubious tag declaration: %s %s */
1312 			warning(85, scltoa(sc), sym->s_name);
1313 		}
1314 	}
1315 
1316 	n = 1;
1317 	for (arg = args; arg != NULL; arg = arg->s_nxt) {
1318 		if (arg->s_type->t_tspec == VOID) {
1319 			if (n > 1 || arg->s_nxt != NULL) {
1320 				/* "void" must be sole parameter */
1321 				error(60);
1322 				arg->s_type = gettyp(INT);
1323 			}
1324 		}
1325 		n++;
1326 	}
1327 
1328 	/* return NULL if first param is VOID */
1329 	return (args != NULL && args->s_type->t_tspec != VOID ? args : NULL);
1330 }
1331 
1332 /*
1333  * Called for old style function declarations.
1334  */
1335 static void
1336 osfunc(sym_t *decl, sym_t *args)
1337 {
1338 
1339 	/*
1340 	 * Remember list of params only if this is really seams to be
1341 	 * a function definition.
1342 	 */
1343 	if (dcs->d_nxt->d_ctx == EXTERN &&
1344 	    decl->s_type == dcs->d_nxt->d_type) {
1345 		/*
1346 		 * We assume that this becomes a function definition. If
1347 		 * we are wrong, its corrected in chkfdef().
1348 		 */
1349 		if (args != NULL) {
1350 			decl->s_osdef = 1;
1351 			decl->s_args = args;
1352 		}
1353 	} else {
1354 		if (args != NULL)
1355 			/* function prototype parameters must have types */
1356 			warning(62);
1357 	}
1358 }
1359 
1360 /*
1361  * Lists of Identifiers in functions declarations are allowed only if
1362  * its also a function definition. If this is not the case, print a
1363  * error message.
1364  */
1365 void
1366 chkfdef(sym_t *sym, int msg)
1367 {
1368 
1369 	if (sym->s_osdef) {
1370 		if (msg) {
1371 			/* incomplete or misplaced function definition */
1372 			error(22);
1373 		}
1374 		sym->s_osdef = 0;
1375 		sym->s_args = NULL;
1376 	}
1377 }
1378 
1379 /*
1380  * Process the name in a declarator.
1381  * If the symbol does already exists, a new one is created.
1382  * The symbol becomes one of the storage classes EXTERN, STATIC, AUTO or
1383  * TYPEDEF.
1384  * s_def and s_reg are valid after dname().
1385  */
1386 sym_t *
1387 dname(sym_t *sym)
1388 {
1389 	scl_t	sc = NOSCL;
1390 
1391 	if (sym->s_scl == NOSCL) {
1392 		dcs->d_rdcsym = NULL;
1393 	} else if (sym->s_defarg) {
1394 		sym->s_defarg = 0;
1395 		dcs->d_rdcsym = NULL;
1396 	} else {
1397 		dcs->d_rdcsym = sym;
1398 		sym = pushdown(sym);
1399 	}
1400 
1401 	switch (dcs->d_ctx) {
1402 	case MOS:
1403 	case MOU:
1404 		/* Parent setzen */
1405 		sym->s_styp = dcs->d_tagtyp->t_str;
1406 		sym->s_def = DEF;
1407 		sym->s_value.v_tspec = INT;
1408 		sc = dcs->d_ctx;
1409 		break;
1410 	case EXTERN:
1411 		/*
1412 		 * static and external symbols without "extern" are
1413 		 * considered to be tentative defined, external
1414 		 * symbols with "extern" are declared, and typedef names
1415 		 * are defined. Tentative defined and declared symbols
1416 		 * may become defined if an initializer is present or
1417 		 * this is a function definition.
1418 		 */
1419 		if ((sc = dcs->d_scl) == NOSCL) {
1420 			sc = EXTERN;
1421 			sym->s_def = TDEF;
1422 		} else if (sc == STATIC) {
1423 			sym->s_def = TDEF;
1424 		} else if (sc == TYPEDEF) {
1425 			sym->s_def = DEF;
1426 		} else if (sc == EXTERN) {
1427 			sym->s_def = DECL;
1428 		} else {
1429 			LERROR("dname()");
1430 		}
1431 		break;
1432 	case PARG:
1433 		sym->s_arg = 1;
1434 		/* FALLTHROUGH */
1435 	case ARG:
1436 		if ((sc = dcs->d_scl) == NOSCL) {
1437 			sc = AUTO;
1438 		} else if (sc == REG) {
1439 			sym->s_reg = 1;
1440 			sc = AUTO;
1441 		} else {
1442 			LERROR("dname()");
1443 		}
1444 		sym->s_def = DEF;
1445 		break;
1446 	case AUTO:
1447 		if ((sc = dcs->d_scl) == NOSCL) {
1448 			/*
1449 			 * XXX somewhat ugly because we dont know whether
1450 			 * this is AUTO or EXTERN (functions). If we are
1451 			 * wrong it must be corrected in decl1loc(), where
1452 			 * we have the necessary type information.
1453 			 */
1454 			sc = AUTO;
1455 			sym->s_def = DEF;
1456 		} else if (sc == AUTO || sc == STATIC || sc == TYPEDEF) {
1457 			sym->s_def = DEF;
1458 		} else if (sc == REG) {
1459 			sym->s_reg = 1;
1460 			sc = AUTO;
1461 			sym->s_def = DEF;
1462 		} else if (sc == EXTERN) {
1463 			sym->s_def = DECL;
1464 		} else {
1465 			LERROR("dname()");
1466 		}
1467 		break;
1468 	default:
1469 		LERROR("dname()");
1470 	}
1471 	sym->s_scl = sc;
1472 
1473 	sym->s_type = dcs->d_type;
1474 
1475 	dcs->d_fpsyms = NULL;
1476 
1477 	return (sym);
1478 }
1479 
1480 /*
1481  * Process a name in the list of formal params in an old style function
1482  * definition.
1483  */
1484 sym_t *
1485 iname(sym_t *sym)
1486 {
1487 
1488 	if (sym->s_scl != NOSCL) {
1489 		if (blklev == sym->s_blklev) {
1490 			/* redeclaration of formal parameter %s */
1491 			error(21, sym->s_name);
1492 			if (!sym->s_defarg)
1493 				LERROR("iname()");
1494 		}
1495 		sym = pushdown(sym);
1496 	}
1497 	sym->s_type = gettyp(INT);
1498 	sym->s_scl = AUTO;
1499 	sym->s_def = DEF;
1500 	sym->s_defarg = sym->s_arg = 1;
1501 	return (sym);
1502 }
1503 
1504 /*
1505  * Create the type of a tag.
1506  *
1507  * tag points to the symbol table entry of the tag
1508  * kind is the kind of the tag (STRUCT/UNION/ENUM)
1509  * decl is 1 if the type of the tag will be completed in this declaration
1510  * (the following token is T_LBRACE)
1511  * semi is 1 if the following token is T_SEMI
1512  */
1513 type_t *
1514 mktag(sym_t *tag, tspec_t kind, int decl, int semi)
1515 {
1516 	scl_t	scl = NOSCL;
1517 	type_t	*tp;
1518 
1519 	if (kind == STRUCT) {
1520 		scl = STRTAG;
1521 	} else if (kind == UNION) {
1522 		scl = UNIONTAG;
1523 	} else if (kind == ENUM) {
1524 		scl = ENUMTAG;
1525 	} else {
1526 		LERROR("mktag()");
1527 	}
1528 
1529 	if (tag != NULL) {
1530 		if (tag->s_scl != NOSCL) {
1531 			tag = newtag(tag, scl, decl, semi);
1532 		} else {
1533 			/* a new tag, no empty declaration */
1534 			dcs->d_nxt->d_nedecl = 1;
1535 			if (scl == ENUMTAG && !decl) {
1536 				if (!tflag && (sflag || pflag))
1537 					/* forward reference to enum type */
1538 					warning(42);
1539 			}
1540 		}
1541 		if (tag->s_scl == NOSCL) {
1542 			tag->s_scl = scl;
1543 			tag->s_type = tp = getblk(sizeof (type_t));
1544 		} else {
1545 			tp = tag->s_type;
1546 		}
1547 	} else {
1548 		tag = getblk(sizeof (sym_t));
1549 		tag->s_name = unnamed;
1550 		UNIQUE_CURR_POS(tag->s_dpos);
1551 		tag->s_kind = FTAG;
1552 		tag->s_scl = scl;
1553 		tag->s_blklev = -1;
1554 		tag->s_type = tp = getblk(sizeof (type_t));
1555 		dcs->d_nxt->d_nedecl = 1;
1556 	}
1557 
1558 	if (tp->t_tspec == NOTSPEC) {
1559 		tp->t_tspec = kind;
1560 		if (kind != ENUM) {
1561 			tp->t_str = getblk(sizeof (str_t));
1562 			tp->t_str->align = CHAR_BIT;
1563 			tp->t_str->stag = tag;
1564 		} else {
1565 			tp->t_isenum = 1;
1566 			tp->t_enum = getblk(sizeof (enum_t));
1567 			tp->t_enum->etag = tag;
1568 		}
1569 		/* ist unvollstaendiger Typ */
1570 		setcompl(tp, 1);
1571 	}
1572 
1573 	return (tp);
1574 }
1575 
1576 /*
1577  * Checks all possible cases of tag redeclarations.
1578  * decl is 1 if T_LBRACE follows
1579  * semi is 1 if T_SEMI follows
1580  */
1581 static sym_t *
1582 newtag(sym_t *tag, scl_t scl, int decl, int semi)
1583 {
1584 
1585 	if (tag->s_blklev < blklev) {
1586 		if (semi) {
1587 			/* "struct a;" */
1588 			if (!tflag) {
1589 				if (!sflag)
1590 					/* decl. introduces new type ... */
1591 					warning(44, scltoa(scl), tag->s_name);
1592 				tag = pushdown(tag);
1593 			} else if (tag->s_scl != scl) {
1594 				/* base type is really "%s %s" */
1595 				warning(45, scltoa(tag->s_scl), tag->s_name);
1596 			}
1597 			dcs->d_nxt->d_nedecl = 1;
1598 		} else if (decl) {
1599 			/* "struct a { ... } " */
1600 			if (hflag)
1601 				/* redefinition hides earlier one: %s */
1602 				warning(43, tag->s_name);
1603 			tag = pushdown(tag);
1604 			dcs->d_nxt->d_nedecl = 1;
1605 		} else if (tag->s_scl != scl) {
1606 			/* base type is really "%s %s" */
1607 			warning(45, scltoa(tag->s_scl), tag->s_name);
1608 			/* declaration introduces new type in ANSI C: %s %s */
1609 			if (!sflag)
1610 				warning(44, scltoa(scl), tag->s_name);
1611 			tag = pushdown(tag);
1612 			dcs->d_nxt->d_nedecl = 1;
1613 		}
1614 	} else {
1615 		if (tag->s_scl != scl) {
1616 			/* (%s) tag redeclared */
1617 			error(46, scltoa(tag->s_scl));
1618 			prevdecl(-1, tag);
1619 			tag = pushdown(tag);
1620 			dcs->d_nxt->d_nedecl = 1;
1621 		} else if (decl && !incompl(tag->s_type)) {
1622 			/* (%s) tag redeclared */
1623 			error(46, scltoa(tag->s_scl));
1624 			prevdecl(-1, tag);
1625 			tag = pushdown(tag);
1626 			dcs->d_nxt->d_nedecl = 1;
1627 		} else if (semi || decl) {
1628 			dcs->d_nxt->d_nedecl = 1;
1629 		}
1630 	}
1631 	return (tag);
1632 }
1633 
1634 const char *
1635 scltoa(scl_t sc)
1636 {
1637 	const	char *s;
1638 
1639 	switch (sc) {
1640 	case EXTERN:	s = "extern";	break;
1641 	case STATIC:	s = "static";	break;
1642 	case AUTO:	s = "auto";	break;
1643 	case REG:	s = "register";	break;
1644 	case TYPEDEF:	s = "typedef";	break;
1645 	case STRTAG:	s = "struct";	break;
1646 	case UNIONTAG:	s = "union";	break;
1647 	case ENUMTAG:	s = "enum";	break;
1648 	default:	LERROR("tagttoa()");
1649 	}
1650 	return (s);
1651 }
1652 
1653 /*
1654  * Completes the type of a tag in a struct/union/enum declaration.
1655  * tp points to the type of the, tag, fmem to the list of members/enums.
1656  */
1657 type_t *
1658 compltag(type_t *tp, sym_t *fmem)
1659 {
1660 	tspec_t	t;
1661 	str_t	*sp;
1662 	int	n;
1663 	sym_t	*mem;
1664 
1665 	/* from now a complete type */
1666 	setcompl(tp, 0);
1667 
1668 	if ((t = tp->t_tspec) != ENUM) {
1669 		align(dcs->d_stralign, 0);
1670 		sp = tp->t_str;
1671 		sp->align = dcs->d_stralign;
1672 		sp->size = dcs->d_offset;
1673 		sp->memb = fmem;
1674 		if (sp->size == 0) {
1675 			/* zero sized %s */
1676 			(void)c99ism(47, ttab[t].tt_name);
1677 		} else {
1678 			n = 0;
1679 			for (mem = fmem; mem != NULL; mem = mem->s_nxt) {
1680 				if (mem->s_name != unnamed)
1681 					n++;
1682 			}
1683 			if (n == 0) {
1684 				/* %s has no named members */
1685 				warning(65,
1686 					t == STRUCT ? "structure" : "union");
1687 			}
1688 		}
1689 	} else {
1690 		tp->t_enum->elem = fmem;
1691 	}
1692 	return (tp);
1693 }
1694 
1695 /*
1696  * Processes the name of an enumerator in en enum declaration.
1697  *
1698  * sym points to the enumerator
1699  * val is the value of the enumerator
1700  * impl is 1 if the value of the enumerator was not explicit specified.
1701  */
1702 sym_t *
1703 ename(sym_t *sym, int val, int impl)
1704 {
1705 
1706 	if (sym->s_scl) {
1707 		if (sym->s_blklev == blklev) {
1708 			/* no hflag, because this is illegal!!! */
1709 			if (sym->s_arg) {
1710 				/* enumeration constant hides parameter: %s */
1711 				warning(57, sym->s_name);
1712 			} else {
1713 				/* redeclaration of %s */
1714 				error(27, sym->s_name);
1715 				/*
1716 				 * inside blocks it should not too complicated
1717 				 * to find the position of the previous
1718 				 * declaration
1719 				 */
1720 				if (blklev == 0)
1721 					prevdecl(-1, sym);
1722 			}
1723 		} else {
1724 			if (hflag)
1725 				/* redefinition hides earlier one: %s */
1726 				warning(43, sym->s_name);
1727 		}
1728 		sym = pushdown(sym);
1729 	}
1730 	sym->s_scl = ENUMCON;
1731 	sym->s_type = dcs->d_tagtyp;
1732 	sym->s_value.v_tspec = INT;
1733 	sym->s_value.v_quad = val;
1734 	if (impl && val - 1 == INT_MAX) {
1735 		/* overflow in enumeration values: %s */
1736 		warning(48, sym->s_name);
1737 	}
1738 	enumval = val + 1;
1739 	return (sym);
1740 }
1741 
1742 /*
1743  * Process a single external declarator.
1744  */
1745 void
1746 decl1ext(sym_t *dsym, int initflg)
1747 {
1748 	int	warn, rval, redec;
1749 	sym_t	*rdsym;
1750 
1751 	chkfdef(dsym, 1);
1752 
1753 	chktyp(dsym);
1754 
1755 	if (initflg && !(initerr = chkinit(dsym)))
1756 		dsym->s_def = DEF;
1757 
1758 	/*
1759 	 * Declarations of functions are marked as "tentative" in dname().
1760 	 * This is wrong because there are no tentative function
1761 	 * definitions.
1762 	 */
1763 	if (dsym->s_type->t_tspec == FUNC && dsym->s_def == TDEF)
1764 		dsym->s_def = DECL;
1765 
1766 	if (dcs->d_inline) {
1767 		if (dsym->s_type->t_tspec == FUNC) {
1768 			dsym->s_inline = 1;
1769 		} else {
1770 			/* variable declared inline: %s */
1771 			warning(268, dsym->s_name);
1772 		}
1773 	}
1774 
1775 	/* Write the declaration into the output file */
1776 	if (plibflg && llibflg &&
1777 	    dsym->s_type->t_tspec == FUNC && dsym->s_type->t_proto) {
1778 		/*
1779 		 * With both LINTLIBRARY and PROTOLIB the prototyp is
1780 		 * written as a function definition to the output file.
1781 		 */
1782 		rval = dsym->s_type->t_subt->t_tspec != VOID;
1783 		outfdef(dsym, &dsym->s_dpos, rval, 0, NULL);
1784 	} else {
1785 		outsym(dsym, dsym->s_scl, dsym->s_def);
1786 	}
1787 
1788 	if ((rdsym = dcs->d_rdcsym) != NULL) {
1789 
1790 		/*
1791 		 * If the old symbol stems from a old style function definition
1792 		 * we have remembered the params in rdsmy->s_args and compare
1793 		 * them with the params of the prototype.
1794 		 */
1795 		if (rdsym->s_osdef && dsym->s_type->t_proto) {
1796 			redec = chkosdef(rdsym, dsym);
1797 		} else {
1798 			redec = 0;
1799 		}
1800 
1801 		if (!redec && !isredec(dsym, (warn = 0, &warn))) {
1802 
1803 			if (warn) {
1804 				/* redeclaration of %s */
1805 				(*(sflag ? error : warning))(27, dsym->s_name);
1806 				prevdecl(-1, rdsym);
1807 			}
1808 
1809 			/*
1810 			 * Overtake the rememberd params if the new symbol
1811 			 * is not a prototype.
1812 			 */
1813 			if (rdsym->s_osdef && !dsym->s_type->t_proto) {
1814 				dsym->s_osdef = rdsym->s_osdef;
1815 				dsym->s_args = rdsym->s_args;
1816 				STRUCT_ASSIGN(dsym->s_dpos, rdsym->s_dpos);
1817 			}
1818 
1819 			/*
1820 			 * Remember the position of the declaration if the
1821 			 * old symbol was a prototype and the new is not.
1822 			 * Also remember the position if the old symbol
1823 			 * was defined and the new is not.
1824 			 */
1825 			if (rdsym->s_type->t_proto && !dsym->s_type->t_proto) {
1826 				STRUCT_ASSIGN(dsym->s_dpos, rdsym->s_dpos);
1827 			} else if (rdsym->s_def == DEF && dsym->s_def != DEF) {
1828 				STRUCT_ASSIGN(dsym->s_dpos, rdsym->s_dpos);
1829 			}
1830 
1831 			/*
1832 			 * Copy informations about usage of the name into
1833 			 * the new symbol.
1834 			 */
1835 			cpuinfo(dsym, rdsym);
1836 
1837 			/* Once a name is defined, it remains defined. */
1838 			if (rdsym->s_def == DEF)
1839 				dsym->s_def = DEF;
1840 
1841 			/* once a function is inline, it remains inline */
1842 			if (rdsym->s_inline)
1843 				dsym->s_inline = 1;
1844 
1845 			compltyp(dsym, rdsym);
1846 
1847 		}
1848 
1849 		rmsym(rdsym);
1850 	}
1851 
1852 	if (dsym->s_scl == TYPEDEF) {
1853 		dsym->s_type = duptyp(dsym->s_type);
1854 		dsym->s_type->t_typedef = 1;
1855 		settdsym(dsym->s_type, dsym);
1856 	}
1857 
1858 }
1859 
1860 /*
1861  * Copies informations about usage into a new symbol table entry of
1862  * the same symbol.
1863  */
1864 void
1865 cpuinfo(sym_t *sym, sym_t *rdsym)
1866 {
1867 
1868 	sym->s_spos = rdsym->s_spos;
1869 	sym->s_upos = rdsym->s_upos;
1870 	sym->s_set = rdsym->s_set;
1871 	sym->s_used = rdsym->s_used;
1872 }
1873 
1874 /*
1875  * Prints an error and returns 1 if a symbol is redeclared/redefined.
1876  * Otherwise returns 0 and, in some cases of minor problems, prints
1877  * a warning.
1878  */
1879 int
1880 isredec(sym_t *dsym, int *warn)
1881 {
1882 	sym_t	*rsym;
1883 
1884 	if ((rsym = dcs->d_rdcsym)->s_scl == ENUMCON) {
1885 		/* redeclaration of %s */
1886 		error(27, dsym->s_name);
1887 		prevdecl(-1, rsym);
1888 		return (1);
1889 	}
1890 	if (rsym->s_scl == TYPEDEF) {
1891 		/* typedef redeclared: %s */
1892 		error(89, dsym->s_name);
1893 		prevdecl(-1, rsym);
1894 		return (1);
1895 	}
1896 	if (dsym->s_scl == TYPEDEF) {
1897 		/* redeclaration of %s */
1898 		error(27, dsym->s_name);
1899 		prevdecl(-1, rsym);
1900 		return (1);
1901 	}
1902 	if (rsym->s_def == DEF && dsym->s_def == DEF) {
1903 		/* redefinition of %s */
1904 		error(28, dsym->s_name);
1905 		prevdecl(-1, rsym);
1906 		return(1);
1907 	}
1908 	if (!eqtype(rsym->s_type, dsym->s_type, 0, 0, warn)) {
1909 		/* redeclaration of %s */
1910 		error(27, dsym->s_name);
1911 		prevdecl(-1, rsym);
1912 		return(1);
1913 	}
1914 	if (rsym->s_scl == EXTERN && dsym->s_scl == EXTERN)
1915 		return(0);
1916 	if (rsym->s_scl == STATIC && dsym->s_scl == STATIC)
1917 		return(0);
1918 	if (rsym->s_scl == STATIC && dsym->s_def == DECL)
1919 		return(0);
1920 	if (rsym->s_scl == EXTERN && rsym->s_def == DEF) {
1921 		/*
1922 		 * All cases except "int a = 1; static int a;" are catched
1923 		 * above with or without a warning
1924 		 */
1925 		/* redeclaration of %s */
1926 		error(27, dsym->s_name);
1927 		prevdecl(-1, rsym);
1928 		return(1);
1929 	}
1930 	if (rsym->s_scl == EXTERN) {
1931 		/* previously declared extern, becomes static: %s */
1932 		warning(29, dsym->s_name);
1933 		prevdecl(-1, rsym);
1934 		return(0);
1935 	}
1936 	/*
1937 	 * Now its on of:
1938 	 * "static a; int a;", "static a; int a = 1;", "static a = 1; int a;"
1939 	 */
1940 	/* redeclaration of %s; ANSI C requires "static" */
1941 	if (sflag) {
1942 		warning(30, dsym->s_name);
1943 		prevdecl(-1, rsym);
1944 	}
1945 	dsym->s_scl = STATIC;
1946 	return (0);
1947 }
1948 
1949 /*
1950  * Checks if two types are compatible. Returns 0 if not, otherwise 1.
1951  *
1952  * ignqual	ignore qualifiers of type; used for function params
1953  * promot	promote left type; used for comparison of params of
1954  *		old style function definitions with params of prototypes.
1955  * *warn	set to 1 if an old style function declaration is not
1956  *		compatible with a prototype
1957  */
1958 int
1959 eqtype(type_t *tp1, type_t *tp2, int ignqual, int promot, int *warn)
1960 {
1961 	tspec_t	t;
1962 
1963 	while (tp1 != NULL && tp2 != NULL) {
1964 
1965 		t = tp1->t_tspec;
1966 		if (promot) {
1967 			if (t == FLOAT) {
1968 				t = DOUBLE;
1969 			} else if (t == CHAR || t == SCHAR) {
1970 				t = INT;
1971 			} else if (t == UCHAR) {
1972 				t = tflag ? UINT : INT;
1973 			} else if (t == SHORT) {
1974 				t = INT;
1975 			} else if (t == USHORT) {
1976 				/* CONSTCOND */
1977 				t = INT_MAX < USHRT_MAX || tflag ? UINT : INT;
1978 			}
1979 		}
1980 
1981 		if (t != tp2->t_tspec)
1982 			return (0);
1983 
1984 		if (tp1->t_const != tp2->t_const && !ignqual && !tflag)
1985 			return (0);
1986 
1987 		if (tp1->t_volatile != tp2->t_volatile && !ignqual && !tflag)
1988 			return (0);
1989 
1990 		if (t == STRUCT || t == UNION)
1991 			return (tp1->t_str == tp2->t_str);
1992 
1993 		if (t == ARRAY && tp1->t_dim != tp2->t_dim) {
1994 			if (tp1->t_dim != 0 && tp2->t_dim != 0)
1995 				return (0);
1996 		}
1997 
1998 		/* dont check prototypes for traditional */
1999 		if (t == FUNC && !tflag) {
2000 			if (tp1->t_proto && tp2->t_proto) {
2001 				if (!eqargs(tp1, tp2, warn))
2002 					return (0);
2003 			} else if (tp1->t_proto) {
2004 				if (!mnoarg(tp1, warn))
2005 					return (0);
2006 			} else if (tp2->t_proto) {
2007 				if (!mnoarg(tp2, warn))
2008 					return (0);
2009 			}
2010 		}
2011 
2012 		tp1 = tp1->t_subt;
2013 		tp2 = tp2->t_subt;
2014 		ignqual = promot = 0;
2015 
2016 	}
2017 
2018 	return (tp1 == tp2);
2019 }
2020 
2021 /*
2022  * Compares the parameter types of two prototypes.
2023  */
2024 static int
2025 eqargs(type_t *tp1, type_t *tp2, int *warn)
2026 {
2027 	sym_t	*a1, *a2;
2028 
2029 	if (tp1->t_vararg != tp2->t_vararg)
2030 		return (0);
2031 
2032 	a1 = tp1->t_args;
2033 	a2 = tp2->t_args;
2034 
2035 	while (a1 != NULL && a2 != NULL) {
2036 
2037 		if (eqtype(a1->s_type, a2->s_type, 1, 0, warn) == 0)
2038 			return (0);
2039 
2040 		a1 = a1->s_nxt;
2041 		a2 = a2->s_nxt;
2042 
2043 	}
2044 
2045 	return (a1 == a2);
2046 }
2047 
2048 /*
2049  * mnoarg() (matches functions with no argument type information)
2050  * returns 1 if all parameters of a prototype are compatible with
2051  * and old style function declaration.
2052  * This is the case if following conditions are met:
2053  *	1. the prototype must have a fixed number of parameters
2054  *	2. no parameter is of type float
2055  *	3. no parameter is converted to another type if integer promotion
2056  *	   is applied on it
2057  */
2058 static int
2059 mnoarg(type_t *tp, int *warn)
2060 {
2061 	sym_t	*arg;
2062 	tspec_t	t;
2063 
2064 	if (tp->t_vararg) {
2065 		if (warn != NULL)
2066 			*warn = 1;
2067 	}
2068 	for (arg = tp->t_args; arg != NULL; arg = arg->s_nxt) {
2069 		if ((t = arg->s_type->t_tspec) == FLOAT ||
2070 		    t == CHAR || t == SCHAR || t == UCHAR ||
2071 		    t == SHORT || t == USHORT) {
2072 			if (warn != NULL)
2073 				*warn = 1;
2074 		}
2075 	}
2076 	return (1);
2077 }
2078 
2079 /*
2080  * Compares a prototype declaration with the remembered arguments of
2081  * a previous old style function definition.
2082  */
2083 static int
2084 chkosdef(sym_t *rdsym, sym_t *dsym)
2085 {
2086 	sym_t	*args, *pargs, *arg, *parg;
2087 	int	narg, nparg, n;
2088 	int	warn, msg;
2089 
2090 	args = rdsym->s_args;
2091 	pargs = dsym->s_type->t_args;
2092 
2093 	msg = 0;
2094 
2095 	narg = nparg = 0;
2096 	for (arg = args; arg != NULL; arg = arg->s_nxt)
2097 		narg++;
2098 	for (parg = pargs; parg != NULL; parg = parg->s_nxt)
2099 		nparg++;
2100 	if (narg != nparg) {
2101 		/* prototype does not match old-style definition */
2102 		error(63);
2103 		msg = 1;
2104 		goto end;
2105 	}
2106 
2107 	arg = args;
2108 	parg = pargs;
2109 	n = 1;
2110 	while (narg--) {
2111 		warn = 0;
2112 		/*
2113 		 * If it does not match due to promotion and sflag is
2114 		 * not set we print only a warning.
2115 		 */
2116 		if (!eqtype(arg->s_type, parg->s_type, 1, 1, &warn) || warn) {
2117 			/* prototype does not match old-style def., arg #%d */
2118 			error(299, n);
2119 			msg = 1;
2120 		}
2121 		arg = arg->s_nxt;
2122 		parg = parg->s_nxt;
2123 		n++;
2124 	}
2125 
2126  end:
2127 	if (msg)
2128 		/* old style definition */
2129 		prevdecl(300, rdsym);
2130 
2131 	return (msg);
2132 }
2133 
2134 /*
2135  * Complets a type by copying the dimension and prototype information
2136  * from a second compatible type.
2137  *
2138  * Following lines are legal:
2139  *  "typedef a[]; a b; a b[10]; a c; a c[20];"
2140  *  "typedef ft(); ft f; f(int); ft g; g(long);"
2141  * This means that, if a type is completed, the type structure must
2142  * be duplicated.
2143  */
2144 void
2145 compltyp(sym_t *dsym, sym_t *ssym)
2146 {
2147 	type_t	**dstp, *src;
2148 	type_t	*dst;
2149 
2150 	dstp = &dsym->s_type;
2151 	src = ssym->s_type;
2152 
2153 	while ((dst = *dstp) != NULL) {
2154 		if (src == NULL || dst->t_tspec != src->t_tspec)
2155 			LERROR("compltyp()");
2156 		if (dst->t_tspec == ARRAY) {
2157 			if (dst->t_dim == 0 && src->t_dim != 0) {
2158 				*dstp = dst = duptyp(dst);
2159 				dst->t_dim = src->t_dim;
2160 				/* now a complete Typ */
2161 				setcompl(dst, 0);
2162 			}
2163 		} else if (dst->t_tspec == FUNC) {
2164 			if (!dst->t_proto && src->t_proto) {
2165 				*dstp = dst = duptyp(dst);
2166 				dst->t_proto = 1;
2167 				dst->t_args = src->t_args;
2168 			}
2169 		}
2170 		dstp = &dst->t_subt;
2171 		src = src->t_subt;
2172 	}
2173 }
2174 
2175 /*
2176  * Completes the declaration of a single argument.
2177  */
2178 sym_t *
2179 decl1arg(sym_t *sym, int initflg)
2180 {
2181 	tspec_t	t;
2182 
2183 	chkfdef(sym, 1);
2184 
2185 	chktyp(sym);
2186 
2187 	if (dcs->d_rdcsym != NULL && dcs->d_rdcsym->s_blklev == blklev) {
2188 		/* redeclaration of formal parameter %s */
2189 		error(237, sym->s_name);
2190 		rmsym(dcs->d_rdcsym);
2191 		sym->s_arg = 1;
2192 	}
2193 
2194 	if (!sym->s_arg) {
2195 		/* declared argument %s is missing */
2196 		error(53, sym->s_name);
2197 		sym->s_arg = 1;
2198 	}
2199 
2200 	if (initflg) {
2201 		/* cannot initialize parameter: %s */
2202 		error(52, sym->s_name);
2203 		initerr = 1;
2204 	}
2205 
2206 	if ((t = sym->s_type->t_tspec) == ARRAY) {
2207 		sym->s_type = incref(sym->s_type->t_subt, PTR);
2208 	} else if (t == FUNC) {
2209 		if (tflag)
2210 			/* a function is declared as an argument: %s */
2211 			warning(50, sym->s_name);
2212 		sym->s_type = incref(sym->s_type, PTR);
2213 	} else if (t == FLOAT) {
2214 		if (tflag)
2215 			sym->s_type = gettyp(DOUBLE);
2216 	}
2217 
2218 	if (dcs->d_inline)
2219 		/* argument declared inline: %s */
2220 		warning(269, sym->s_name);
2221 
2222 	/*
2223 	 * Arguments must have complete types. lengths() prints the needed
2224 	 * error messages (null dimension is impossible because arrays are
2225 	 * converted to pointers).
2226 	 */
2227 	if (sym->s_type->t_tspec != VOID)
2228 		(void)length(sym->s_type, sym->s_name);
2229 
2230 	setsflg(sym);
2231 
2232 	return (sym);
2233 }
2234 
2235 /*
2236  * Does some checks for lint directives which apply to functions.
2237  * Processes arguments in old style function definitions which default
2238  * to int.
2239  * Checks compatiblility of old style function definition with previous
2240  * prototype.
2241  */
2242 void
2243 cluparg(void)
2244 {
2245 	sym_t	*args, *arg, *pargs, *parg;
2246 	int	narg, nparg, n, msg;
2247 	tspec_t	t;
2248 
2249 	args = funcsym->s_args;
2250 	pargs = funcsym->s_type->t_args;
2251 
2252 	/* check for illegal combinations of lint directives */
2253 	if (prflstrg != -1 && scflstrg != -1) {
2254 		/* can't be used together: ** PRINTFLIKE ** ** SCANFLIKE ** */
2255 		warning(289);
2256 		prflstrg = scflstrg = -1;
2257 	}
2258 	if (nvararg != -1 && (prflstrg != -1 || scflstrg != -1)) {
2259 		/* dubious use of ** VARARGS ** with ** %s ** */
2260 		warning(288, prflstrg != -1 ? "PRINTFLIKE" : "SCANFLIKE");
2261 		nvararg = -1;
2262 	}
2263 
2264 	/*
2265 	 * check if the argument of a lint directive is compatible with the
2266 	 * number of arguments.
2267 	 */
2268 	narg = 0;
2269 	for (arg = dcs->d_fargs; arg != NULL; arg = arg->s_nxt)
2270 		narg++;
2271 	if (nargusg > narg) {
2272 		/* argument number mismatch with directive: ** %s ** */
2273 		warning(283, "ARGSUSED");
2274 		nargusg = 0;
2275 	}
2276 	if (nvararg > narg) {
2277 		/* argument number mismatch with directive: ** %s ** */
2278 		warning(283, "VARARGS");
2279 		nvararg = 0;
2280 	}
2281 	if (prflstrg > narg) {
2282 		/* argument number mismatch with directive: ** %s ** */
2283 		warning(283, "PRINTFLIKE");
2284 		prflstrg = -1;
2285 	} else if (prflstrg == 0) {
2286 		prflstrg = -1;
2287 	}
2288 	if (scflstrg > narg) {
2289 		/* argument number mismatch with directive: ** %s ** */
2290 		warning(283, "SCANFLIKE");
2291 		scflstrg = -1;
2292 	} else if (scflstrg == 0) {
2293 		scflstrg = -1;
2294 	}
2295 	if (prflstrg != -1 || scflstrg != -1) {
2296 		narg = prflstrg != -1 ? prflstrg : scflstrg;
2297 		arg = dcs->d_fargs;
2298 		for (n = 1; n < narg; n++)
2299 			arg = arg->s_nxt;
2300 		if (arg->s_type->t_tspec != PTR ||
2301 		    ((t = arg->s_type->t_subt->t_tspec) != CHAR &&
2302 		     t != UCHAR && t != SCHAR)) {
2303 			/* arg. %d must be 'char *' for PRINTFLIKE/SCANFLIKE */
2304 			warning(293, narg);
2305 			prflstrg = scflstrg = -1;
2306 		}
2307 	}
2308 
2309 	/*
2310 	 * print a warning for each argument off an old style function
2311 	 * definition which defaults to int
2312 	 */
2313 	for (arg = args; arg != NULL; arg = arg->s_nxt) {
2314 		if (arg->s_defarg) {
2315 			/* argument type defaults to int: %s */
2316 			warning(32, arg->s_name);
2317 			arg->s_defarg = 0;
2318 			setsflg(arg);
2319 		}
2320 	}
2321 
2322 	/*
2323 	 * If this is an old style function definition and a prototyp
2324 	 * exists, compare the types of arguments.
2325 	 */
2326 	if (funcsym->s_osdef && funcsym->s_type->t_proto) {
2327 		/*
2328 		 * If the number of arguments does not macht, we need not
2329 		 * continue.
2330 		 */
2331 		narg = nparg = 0;
2332 		msg = 0;
2333 		for (parg = pargs; parg != NULL; parg = parg->s_nxt)
2334 			nparg++;
2335 		for (arg = args; arg != NULL; arg = arg->s_nxt)
2336 			narg++;
2337 		if (narg != nparg) {
2338 			/* parameter mismatch: %d declared, %d defined */
2339 			error(51, nparg, narg);
2340 			msg = 1;
2341 		} else {
2342 			parg = pargs;
2343 			arg = args;
2344 			while (narg--) {
2345 				msg |= chkptdecl(arg, parg);
2346 				parg = parg->s_nxt;
2347 				arg = arg->s_nxt;
2348 			}
2349 		}
2350 		if (msg)
2351 			/* prototype declaration */
2352 			prevdecl(285, dcs->d_rdcsym);
2353 
2354 		/* from now the prototype is valid */
2355 		funcsym->s_osdef = 0;
2356 		funcsym->s_args = NULL;
2357 
2358 	}
2359 
2360 }
2361 
2362 /*
2363  * Checks compatibility of an old style function definition with a previous
2364  * prototype declaration.
2365  * Returns 1 if the position of the previous declaration should be reported.
2366  */
2367 static int
2368 chkptdecl(sym_t *arg, sym_t *parg)
2369 {
2370 	type_t	*tp, *ptp;
2371 	int	warn, msg;
2372 
2373 	tp = arg->s_type;
2374 	ptp = parg->s_type;
2375 
2376 	msg = 0;
2377 	warn = 0;
2378 
2379 	if (!eqtype(tp, ptp, 1, 1, &warn)) {
2380 		if (eqtype(tp, ptp, 1, 0, &warn)) {
2381 			/* type does not match prototype: %s */
2382 			msg = gnuism(58, arg->s_name);
2383 		} else {
2384 			/* type does not match prototype: %s */
2385 			error(58, arg->s_name);
2386 			msg = 1;
2387 		}
2388 	} else if (warn) {
2389 		/* type does not match prototype: %s */
2390 		(*(sflag ? error : warning))(58, arg->s_name);
2391 		msg = 1;
2392 	}
2393 
2394 	return (msg);
2395 }
2396 
2397 /*
2398  * Completes a single local declaration/definition.
2399  */
2400 void
2401 decl1loc(sym_t *dsym, int initflg)
2402 {
2403 
2404 	/* Correct a mistake done in dname(). */
2405 	if (dsym->s_type->t_tspec == FUNC) {
2406 		dsym->s_def = DECL;
2407 		if (dcs->d_scl == NOSCL)
2408 			dsym->s_scl = EXTERN;
2409 	}
2410 
2411 	if (dsym->s_type->t_tspec == FUNC) {
2412 		if (dsym->s_scl == STATIC) {
2413 			/* dubious static function at block level: %s */
2414 			warning(93, dsym->s_name);
2415 			dsym->s_scl = EXTERN;
2416 		} else if (dsym->s_scl != EXTERN && dsym->s_scl != TYPEDEF) {
2417 			/* function has illegal storage class: %s */
2418 			error(94, dsym->s_name);
2419 			dsym->s_scl = EXTERN;
2420 		}
2421 	}
2422 
2423 	/*
2424 	 * functions may be declared inline at local scope, although
2425 	 * this has no effect for a later definition of the same
2426 	 * function.
2427 	 * XXX it should have an effect if tflag is set. this would
2428 	 * also be the way gcc behaves.
2429 	 */
2430 	if (dcs->d_inline) {
2431 		if (dsym->s_type->t_tspec == FUNC) {
2432 			dsym->s_inline = 1;
2433 		} else {
2434 			/* variable declared inline: %s */
2435 			warning(268, dsym->s_name);
2436 		}
2437 	}
2438 
2439 	chkfdef(dsym, 1);
2440 
2441 	chktyp(dsym);
2442 
2443 	if (dcs->d_rdcsym != NULL && dsym->s_scl == EXTERN)
2444 		ledecl(dsym);
2445 
2446 	if (dsym->s_scl == EXTERN) {
2447 		/*
2448 		 * XXX wenn die statische Variable auf Ebene 0 erst
2449 		 * spaeter definiert wird, haben wir die Brille auf.
2450 		 */
2451 		if (dsym->s_xsym == NULL) {
2452 			outsym(dsym, EXTERN, dsym->s_def);
2453 		} else {
2454 			outsym(dsym, dsym->s_xsym->s_scl, dsym->s_def);
2455 		}
2456 	}
2457 
2458 	if (dcs->d_rdcsym != NULL) {
2459 
2460 		if (dcs->d_rdcsym->s_blklev == 0) {
2461 
2462 			switch (dsym->s_scl) {
2463 			case AUTO:
2464 				/* automatic hides external declaration: %s */
2465 				if (hflag)
2466 					warning(86, dsym->s_name);
2467 				break;
2468 			case STATIC:
2469 				/* static hides external declaration: %s */
2470 				if (hflag)
2471 					warning(87, dsym->s_name);
2472 				break;
2473 			case TYPEDEF:
2474 				/* typedef hides  external declaration: %s */
2475 				if (hflag)
2476 					warning(88, dsym->s_name);
2477 				break;
2478 			case EXTERN:
2479 				/*
2480 				 * Warnings and errors are printed in ledecl()
2481 				 */
2482 				break;
2483 			default:
2484 				LERROR("decl1loc()");
2485 			}
2486 
2487 		} else if (dcs->d_rdcsym->s_blklev == blklev) {
2488 
2489 			/* no hflag, because its illegal! */
2490 			if (dcs->d_rdcsym->s_arg) {
2491 				/*
2492 				 * if !tflag, a "redeclaration of %s" error
2493 				 * is produced below
2494 				 */
2495 				if (tflag) {
2496 					if (hflag)
2497 						/* decl. hides parameter: %s */
2498 						warning(91, dsym->s_name);
2499 					rmsym(dcs->d_rdcsym);
2500 				}
2501 			}
2502 
2503 		} else if (dcs->d_rdcsym->s_blklev < blklev) {
2504 
2505 			if (hflag)
2506 				/* declaration hides earlier one: %s */
2507 				warning(95, dsym->s_name);
2508 
2509 		}
2510 
2511 		if (dcs->d_rdcsym->s_blklev == blklev) {
2512 
2513 			/* redeclaration of %s */
2514 			error(27, dsym->s_name);
2515 			rmsym(dcs->d_rdcsym);
2516 
2517 		}
2518 
2519 	}
2520 
2521 	if (initflg && !(initerr = chkinit(dsym))) {
2522 		dsym->s_def = DEF;
2523 		setsflg(dsym);
2524 	}
2525 
2526 	if (dsym->s_scl == TYPEDEF) {
2527 		dsym->s_type = duptyp(dsym->s_type);
2528 		dsym->s_type->t_typedef = 1;
2529 		settdsym(dsym->s_type, dsym);
2530 	}
2531 
2532 	/*
2533 	 * Before we can check the size we must wait for a initialisation
2534 	 * which may follow.
2535 	 */
2536 }
2537 
2538 /*
2539  * Processes (re)declarations of external Symbols inside blocks.
2540  */
2541 static void
2542 ledecl(sym_t *dsym)
2543 {
2544 	int	eqt, warn;
2545 	sym_t	*esym;
2546 
2547 	/* look for a symbol with the same name */
2548 	esym = dcs->d_rdcsym;
2549 	while (esym != NULL && esym->s_blklev != 0) {
2550 		while ((esym = esym->s_link) != NULL) {
2551 			if (esym->s_kind != FVFT)
2552 				continue;
2553 			if (strcmp(dsym->s_name, esym->s_name) == 0)
2554 				break;
2555 		}
2556 	}
2557 	if (esym == NULL)
2558 		return;
2559 	if (esym->s_scl != EXTERN && esym->s_scl != STATIC) {
2560 		/* gcc accepts this without a warning, pcc prints an error. */
2561 		/* redeclaration of %s */
2562 		warning(27, dsym->s_name);
2563 		prevdecl(-1, esym);
2564 		return;
2565 	}
2566 
2567 	warn = 0;
2568 	eqt = eqtype(esym->s_type, dsym->s_type, 0, 0, &warn);
2569 
2570 	if (!eqt || warn) {
2571 		if (esym->s_scl == EXTERN) {
2572 			/* inconsistent redeclaration of extern: %s */
2573 			warning(90, dsym->s_name);
2574 			prevdecl(-1, esym);
2575 		} else {
2576 			/* inconsistent redeclaration of static: %s */
2577 			warning(92, dsym->s_name);
2578 			prevdecl(-1, esym);
2579 		}
2580 	}
2581 
2582 	if (eqt) {
2583 		/*
2584 		 * Remember the external symbol so we can update usage
2585 		 * information at the end of the block.
2586 		 */
2587 		dsym->s_xsym = esym;
2588 	}
2589 }
2590 
2591 /*
2592  * Print an error or a warning if the symbol cant be initialized due
2593  * to type/storage class. Returnvalue is 1 if an error has been
2594  * detected.
2595  */
2596 static int
2597 chkinit(sym_t *sym)
2598 {
2599 	int	err;
2600 
2601 	err = 0;
2602 
2603 	if (sym->s_type->t_tspec == FUNC) {
2604 		/* cannot initialize function: %s */
2605 		error(24, sym->s_name);
2606 		err = 1;
2607 	} else if (sym->s_scl == TYPEDEF) {
2608 		/* cannot initialize typedef: %s */
2609 		error(25, sym->s_name);
2610 		err = 1;
2611 	} else if (sym->s_scl == EXTERN && sym->s_def == DECL) {
2612 		/* cannot initialize "extern" declaration: %s */
2613 		if (dcs->d_ctx == EXTERN) {
2614 			warning(26, sym->s_name);
2615 		} else {
2616 			error(26, sym->s_name);
2617 			err = 1;
2618 		}
2619 	}
2620 
2621 	return (err);
2622 }
2623 
2624 /*
2625  * Create a symbole for an abstract declaration.
2626  */
2627 sym_t *
2628 aname(void)
2629 {
2630 	sym_t	*sym;
2631 
2632 	if (dcs->d_ctx != ABSTRACT && dcs->d_ctx != PARG)
2633 		LERROR("aname()");
2634 
2635 	sym = getblk(sizeof (sym_t));
2636 
2637 	sym->s_name = unnamed;
2638 	sym->s_def = DEF;
2639 	sym->s_scl = ABSTRACT;
2640 	sym->s_blklev = -1;
2641 
2642 	if (dcs->d_ctx == PARG)
2643 		sym->s_arg = 1;
2644 
2645 	sym->s_type = dcs->d_type;
2646 	dcs->d_rdcsym = NULL;
2647 	dcs->d_vararg = 0;
2648 
2649 	return (sym);
2650 }
2651 
2652 /*
2653  * Removes anything which has nothing to do on global level.
2654  */
2655 void
2656 globclup(void)
2657 {
2658 
2659 	while (dcs->d_nxt != NULL)
2660 		popdecl();
2661 
2662 	cleanup();
2663 	blklev = 0;
2664 	mblklev = 0;
2665 
2666 	/*
2667 	 * remove all informations about pending lint directives without
2668 	 * warnings.
2669 	 */
2670 	glclup(1);
2671 }
2672 
2673 /*
2674  * Process an abstract type declaration
2675  */
2676 sym_t *
2677 decl1abs(sym_t *sym)
2678 {
2679 
2680 	chkfdef(sym, 1);
2681 	chktyp(sym);
2682 	return (sym);
2683 }
2684 
2685 /*
2686  * Checks size after declarations of variables and their initialisation.
2687  */
2688 void
2689 chksz(sym_t *dsym)
2690 {
2691 
2692 	/*
2693 	 * check size only for symbols which are defined and no function and
2694 	 * not typedef name
2695 	 */
2696 	if (dsym->s_def != DEF)
2697 		return;
2698 	if (dsym->s_scl == TYPEDEF)
2699 		return;
2700 	if (dsym->s_type->t_tspec == FUNC)
2701 		return;
2702 
2703 	if (length(dsym->s_type, dsym->s_name) == 0 &&
2704 	    dsym->s_type->t_tspec == ARRAY && dsym->s_type->t_dim == 0) {
2705 		/* empty array declaration: %s */
2706 		if (tflag) {
2707 			warning(190, dsym->s_name);
2708 		} else {
2709 			error(190, dsym->s_name);
2710 		}
2711 	}
2712 }
2713 
2714 /*
2715  * Mark an object as set if it is not already
2716  */
2717 void
2718 setsflg(sym_t *sym)
2719 {
2720 
2721 	if (!sym->s_set) {
2722 		sym->s_set = 1;
2723 		UNIQUE_CURR_POS(sym->s_spos);
2724 	}
2725 }
2726 
2727 /*
2728  * Mark an object as used if it is not already
2729  */
2730 void
2731 setuflg(sym_t *sym, int fcall, int szof)
2732 {
2733 
2734 	if (!sym->s_used) {
2735 		sym->s_used = 1;
2736 		UNIQUE_CURR_POS(sym->s_upos);
2737 	}
2738 	/*
2739 	 * for function calls another record is written
2740 	 *
2741 	 * XXX Should symbols used in sizeof() treated as used or not?
2742 	 * Probably not, because there is no sense to declare an
2743 	 * external variable only to get their size.
2744 	 */
2745 	if (!fcall && !szof && sym->s_kind == FVFT && sym->s_scl == EXTERN)
2746 		outusg(sym);
2747 }
2748 
2749 /*
2750  * Prints warnings for a list of variables and labels (concatenated
2751  * with s_dlnxt) if these are not used or only set.
2752  */
2753 void
2754 chkusage(dinfo_t *di)
2755 {
2756 	sym_t	*sym;
2757 	int	mknowarn;
2758 
2759 	/* for this warnings LINTED has no effect */
2760 	mknowarn = nowarn;
2761 	nowarn = 0;
2762 
2763 #ifdef DEBUG
2764 	printf("%s, %d: >temp nowarn = 0\n", curr_pos.p_file, curr_pos.p_line);
2765 #endif
2766 	for (sym = di->d_dlsyms; sym != NULL; sym = sym->s_dlnxt)
2767 		chkusg1(di->d_asm, sym);
2768 	nowarn = mknowarn;
2769 #ifdef DEBUG
2770 	printf("%s, %d: <temp nowarn = %d\n", curr_pos.p_file, curr_pos.p_line,
2771 	    nowarn);
2772 #endif
2773 }
2774 
2775 /*
2776  * Prints a warning for a single variable or label if it is not used or
2777  * only set.
2778  */
2779 void
2780 chkusg1(int novar, sym_t *sym)
2781 {
2782 	pos_t	cpos;
2783 
2784 	if (sym->s_blklev == -1)
2785 		return;
2786 
2787 	STRUCT_ASSIGN(cpos, curr_pos);
2788 
2789 	if (sym->s_kind == FVFT) {
2790 		if (sym->s_arg) {
2791 			chkausg(novar, sym);
2792 		} else {
2793 			chkvusg(novar, sym);
2794 		}
2795 	} else if (sym->s_kind == FLAB) {
2796 		chklusg(sym);
2797 	} else if (sym->s_kind == FTAG) {
2798 		chktusg(sym);
2799 	}
2800 
2801 	STRUCT_ASSIGN(curr_pos, cpos);
2802 }
2803 
2804 static void
2805 chkausg(int novar, sym_t *arg)
2806 {
2807 
2808 	if (!arg->s_set)
2809 		LERROR("chkausg()");
2810 
2811 	if (novar)
2812 		return;
2813 
2814 	if (!arg->s_used && vflag) {
2815 		STRUCT_ASSIGN(curr_pos, arg->s_dpos);
2816 		/* argument %s unused in function %s */
2817 		warning(231, arg->s_name, funcsym->s_name);
2818 	}
2819 }
2820 
2821 static void
2822 chkvusg(int novar, sym_t *sym)
2823 {
2824 	scl_t	sc;
2825 	sym_t	*xsym;
2826 
2827 	if (blklev == 0 || sym->s_blklev == 0)
2828 		LERROR("chkvusg()");
2829 
2830 	/* errors in expressions easily cause lots of these warnings */
2831 	if (nerr != 0)
2832 		return;
2833 
2834 	/*
2835 	 * XXX Only variables are checkd, although types should
2836 	 * probably also be checked
2837 	 */
2838 	if ((sc = sym->s_scl) != EXTERN && sc != STATIC &&
2839 	    sc != AUTO && sc != REG) {
2840 		return;
2841 	}
2842 
2843 	if (novar)
2844 		return;
2845 
2846 	if (sc == EXTERN) {
2847 		if (!sym->s_used && !sym->s_set) {
2848 			STRUCT_ASSIGN(curr_pos, sym->s_dpos);
2849 			/* %s unused in function %s */
2850 			warning(192, sym->s_name, funcsym->s_name);
2851 		}
2852 	} else {
2853 		if (sym->s_set && !sym->s_used) {
2854 			STRUCT_ASSIGN(curr_pos, sym->s_spos);
2855 			/* %s set but not used in function %s */
2856 			warning(191, sym->s_name, funcsym->s_name);
2857 		} else if (!sym->s_used) {
2858 			STRUCT_ASSIGN(curr_pos, sym->s_dpos);
2859 			/* %s unused in function %s */
2860 			warning(192, sym->s_name, funcsym->s_name);
2861 		}
2862 	}
2863 
2864 	if (sc == EXTERN) {
2865 		/*
2866 		 * information about usage is taken over into the symbol
2867 		 * tabel entry at level 0 if the symbol was locally declared
2868 		 * as an external symbol.
2869 		 *
2870 		 * XXX This is wrong for symbols declared static at level 0
2871 		 * if the usage information stems from sizeof(). This is
2872 		 * because symbols at level 0 only used in sizeof() are
2873 		 * considered to not be used.
2874 		 */
2875 		if ((xsym = sym->s_xsym) != NULL) {
2876 			if (sym->s_used && !xsym->s_used) {
2877 				xsym->s_used = 1;
2878 				STRUCT_ASSIGN(xsym->s_upos, sym->s_upos);
2879 			}
2880 			if (sym->s_set && !xsym->s_set) {
2881 				xsym->s_set = 1;
2882 				STRUCT_ASSIGN(xsym->s_spos, sym->s_spos);
2883 			}
2884 		}
2885 	}
2886 }
2887 
2888 static void
2889 chklusg(sym_t *lab)
2890 {
2891 
2892 	if (blklev != 1 || lab->s_blklev != 1)
2893 		LERROR("chklusg()");
2894 
2895 	if (lab->s_set && !lab->s_used) {
2896 		STRUCT_ASSIGN(curr_pos, lab->s_spos);
2897 		/* label %s unused in function %s */
2898 		warning(192, lab->s_name, funcsym->s_name);
2899 	} else if (!lab->s_set) {
2900 		STRUCT_ASSIGN(curr_pos, lab->s_upos);
2901 		/* undefined label %s */
2902 		warning(23, lab->s_name);
2903 	}
2904 }
2905 
2906 static void
2907 chktusg(sym_t *sym)
2908 {
2909 
2910 	if (!incompl(sym->s_type))
2911 		return;
2912 
2913 	/* complain alwasy about incomplet tags declared inside blocks */
2914 	if (!zflag || dcs->d_ctx != EXTERN)
2915 		return;
2916 
2917 	STRUCT_ASSIGN(curr_pos, sym->s_dpos);
2918 	switch (sym->s_type->t_tspec) {
2919 	case STRUCT:
2920 		/* struct %s never defined */
2921 		warning(233, sym->s_name);
2922 		break;
2923 	case UNION:
2924 		/* union %s never defined */
2925 		warning(234, sym->s_name);
2926 		break;
2927 	case ENUM:
2928 		/* enum %s never defined */
2929 		warning(235, sym->s_name);
2930 		break;
2931 	default:
2932 		LERROR("chktusg()");
2933 	}
2934 }
2935 
2936 /*
2937  * Called after the entire translation unit has been parsed.
2938  * Changes tentative definitions in definitions.
2939  * Performs some tests on global Symbols. Detected Problems are:
2940  * - defined variables of incomplete type
2941  * - constant variables which are not initialized
2942  * - static symbols which are never used
2943  */
2944 void
2945 chkglsyms(void)
2946 {
2947 	sym_t	*sym;
2948 	pos_t	cpos;
2949 
2950 	if (blklev != 0 || dcs->d_nxt != NULL)
2951 		norecover();
2952 
2953 	STRUCT_ASSIGN(cpos, curr_pos);
2954 
2955 	for (sym = dcs->d_dlsyms; sym != NULL; sym = sym->s_dlnxt) {
2956 		if (sym->s_blklev == -1)
2957 			continue;
2958 		if (sym->s_kind == FVFT) {
2959 			chkglvar(sym);
2960 		} else if (sym->s_kind == FTAG) {
2961 			chktusg(sym);
2962 		} else {
2963 			if (sym->s_kind != FMOS)
2964 				LERROR("chkglsyms()");
2965 		}
2966 	}
2967 
2968 	STRUCT_ASSIGN(curr_pos, cpos);
2969 }
2970 
2971 static void
2972 chkglvar(sym_t *sym)
2973 {
2974 
2975 	if (sym->s_scl == TYPEDEF || sym->s_scl == ENUMCON)
2976 		return;
2977 
2978 	if (sym->s_scl != EXTERN && sym->s_scl != STATIC)
2979 		LERROR("chkglvar()");
2980 
2981 	glchksz(sym);
2982 
2983 	if (sym->s_scl == STATIC) {
2984 		if (sym->s_type->t_tspec == FUNC) {
2985 			if (sym->s_used && sym->s_def != DEF) {
2986 				STRUCT_ASSIGN(curr_pos, sym->s_upos);
2987 				/* static func. called but not def.. */
2988 				error(225, sym->s_name);
2989 			}
2990 		}
2991 		if (!sym->s_used) {
2992 			STRUCT_ASSIGN(curr_pos, sym->s_dpos);
2993 			if (sym->s_type->t_tspec == FUNC) {
2994 				if (sym->s_def == DEF) {
2995 					if (!sym->s_inline)
2996 						/* static function %s unused */
2997 						warning(236, sym->s_name);
2998 				} else {
2999 					/* static function %s decl. but ... */
3000 					warning(290, sym->s_name);
3001 				}
3002 			} else if (!sym->s_set) {
3003 				/* static variable %s unused */
3004 				warning(226, sym->s_name);
3005 			} else {
3006 				/* static variable %s set but not used */
3007 				warning(307, sym->s_name);
3008 			}
3009 		}
3010 		if (!tflag && sym->s_def == TDEF && sym->s_type->t_const) {
3011 			STRUCT_ASSIGN(curr_pos, sym->s_dpos);
3012 			/* const object %s should have initializer */
3013 			warning(227, sym->s_name);
3014 		}
3015 	}
3016 }
3017 
3018 static void
3019 glchksz(sym_t *sym)
3020 {
3021 
3022 	if (sym->s_def == TDEF) {
3023 		if (sym->s_type->t_tspec == FUNC)
3024 			/*
3025 			 * this can happen if an syntax error occurred
3026 			 * after a function declaration
3027 			 */
3028 			return;
3029 		STRUCT_ASSIGN(curr_pos, sym->s_dpos);
3030 		if (length(sym->s_type, sym->s_name) == 0 &&
3031 		    sym->s_type->t_tspec == ARRAY && sym->s_type->t_dim == 0) {
3032 			/* empty array declaration: %s */
3033 			if (tflag || (sym->s_scl == EXTERN && !sflag)) {
3034 				warning(190, sym->s_name);
3035 			} else {
3036 				error(190, sym->s_name);
3037 			}
3038 		}
3039 	}
3040 }
3041 
3042 /*
3043  * Prints information about location of previous definition/declaration.
3044  */
3045 void
3046 prevdecl(int msg, sym_t *psym)
3047 {
3048 	pos_t	cpos;
3049 
3050 	if (!rflag)
3051 		return;
3052 
3053 	STRUCT_ASSIGN(cpos, curr_pos);
3054 	STRUCT_ASSIGN(curr_pos, psym->s_dpos);
3055 	if (msg != -1) {
3056 		message(msg, psym->s_name);
3057 	} else if (psym->s_def == DEF || psym->s_def == TDEF) {
3058 		/* previous definition of %s */
3059 		message(261, psym->s_name);
3060 	} else {
3061 		/* previous declaration of %s */
3062 		message(260, psym->s_name);
3063 	}
3064 	STRUCT_ASSIGN(curr_pos, cpos);
3065 }
3066