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decl.c revision 1.322
      1  1.322    rillig /* $NetBSD: decl.c,v 1.322 2023/06/29 12:52:06 rillig Exp $ */
      2    1.2       cgd 
      3    1.1       cgd /*
      4   1.12       cgd  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
      5    1.1       cgd  * Copyright (c) 1994, 1995 Jochen Pohl
      6    1.1       cgd  * All Rights Reserved.
      7    1.1       cgd  *
      8    1.1       cgd  * Redistribution and use in source and binary forms, with or without
      9    1.1       cgd  * modification, are permitted provided that the following conditions
     10    1.1       cgd  * are met:
     11    1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     12    1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     13    1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     14    1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     15    1.1       cgd  *    documentation and/or other materials provided with the distribution.
     16    1.1       cgd  * 3. All advertising materials mentioning features or use of this software
     17    1.1       cgd  *    must display the following acknowledgement:
     18    1.1       cgd  *      This product includes software developed by Jochen Pohl for
     19    1.1       cgd  *	The NetBSD Project.
     20    1.1       cgd  * 4. The name of the author may not be used to endorse or promote products
     21    1.1       cgd  *    derived from this software without specific prior written permission.
     22    1.1       cgd  *
     23    1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     24    1.1       cgd  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     25    1.1       cgd  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     26    1.1       cgd  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     27    1.1       cgd  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     28    1.1       cgd  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     29    1.1       cgd  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     30    1.1       cgd  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     31    1.1       cgd  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     32    1.1       cgd  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     33    1.1       cgd  */
     34    1.1       cgd 
     35   1.33       jmc #if HAVE_NBTOOL_CONFIG_H
     36   1.33       jmc #include "nbtool_config.h"
     37   1.33       jmc #endif
     38   1.33       jmc 
     39   1.13  christos #include <sys/cdefs.h>
     40  1.281    rillig #if defined(__RCSID)
     41  1.322    rillig __RCSID("$NetBSD: decl.c,v 1.322 2023/06/29 12:52:06 rillig Exp $");
     42    1.1       cgd #endif
     43    1.1       cgd 
     44    1.1       cgd #include <sys/param.h>
     45    1.1       cgd #include <limits.h>
     46    1.1       cgd #include <stdlib.h>
     47    1.1       cgd #include <string.h>
     48    1.1       cgd 
     49    1.1       cgd #include "lint1.h"
     50    1.1       cgd 
     51  1.301    rillig const char unnamed[] = "<unnamed>";
     52    1.1       cgd 
     53  1.111    rillig /* shared type structures for arithmetic types and void */
     54  1.286    rillig static	type_t	typetab[NTSPEC];
     55    1.1       cgd 
     56    1.1       cgd /* value of next enumerator during declaration of enum types */
     57    1.1       cgd int	enumval;
     58    1.1       cgd 
     59    1.1       cgd /*
     60  1.297    rillig  * pointer to innermost element of a stack which contains information local
     61    1.1       cgd  * to nested declarations
     62    1.1       cgd  */
     63    1.1       cgd dinfo_t	*dcs;
     64    1.1       cgd 
     65  1.297    rillig static	type_t	*typedef_error(type_t *, tspec_t);
     66  1.297    rillig static	void	set_first_typedef(type_t *, sym_t *);
     67  1.296    rillig static	void	dcs_align(unsigned int, unsigned int);
     68  1.297    rillig static	sym_t	*new_tag(sym_t *, scl_t, bool, bool);
     69  1.298    rillig static	bool	prototypes_compatible(const type_t *, const type_t *, bool *);
     70  1.297    rillig static	bool	matches_no_arg_function(const type_t *, bool *);
     71  1.122    rillig static	bool	check_old_style_definition(sym_t *, sym_t *);
     72  1.122    rillig static	bool	check_prototype_declaration(sym_t *, sym_t *);
     73  1.267    rillig static	sym_t	*new_style_function(sym_t *);
     74   1.75    rillig static	void	old_style_function(sym_t *, sym_t *);
     75  1.116    rillig static	void	declare_external_in_block(sym_t *);
     76  1.122    rillig static	bool	check_init(sym_t *);
     77  1.122    rillig static	void	check_argument_usage(bool, sym_t *);
     78  1.122    rillig static	void	check_variable_usage(bool, sym_t *);
     79   1.75    rillig static	void	check_label_usage(sym_t *);
     80   1.75    rillig static	void	check_tag_usage(sym_t *);
     81  1.120    rillig static	void	check_global_variable(const sym_t *);
     82  1.120    rillig static	void	check_global_variable_size(const sym_t *);
     83    1.1       cgd 
     84    1.1       cgd /*
     85    1.1       cgd  * initializes all global vars used in declarations
     86    1.1       cgd  */
     87    1.1       cgd void
     88  1.200       rin #ifdef __sh3__
     89  1.200       rin /* XXX port-sh3/56311 */
     90  1.200       rin __attribute__((optimize("O0")))
     91  1.200       rin #endif
     92   1.22     lukem initdecl(void)
     93    1.1       cgd {
     94    1.1       cgd 
     95    1.1       cgd 	/* declaration stack */
     96  1.170    rillig 	dcs = xcalloc(1, sizeof(*dcs));
     97  1.276    rillig 	dcs->d_kind = DK_EXTERN;
     98    1.3       jpo 	dcs->d_ldlsym = &dcs->d_dlsyms;
     99    1.1       cgd 
    100  1.321    rillig 	if (!pflag) {
    101  1.321    rillig 		for (size_t i = 0; i < NTSPEC; i++)
    102  1.321    rillig 			ttab[i].tt_portable_size_in_bits =
    103  1.321    rillig 			    ttab[i].tt_size_in_bits;
    104  1.321    rillig 	}
    105  1.321    rillig 
    106  1.321    rillig 	if (Tflag) {
    107  1.321    rillig 		ttab[BOOL].tt_is_integer = false;
    108  1.321    rillig 		ttab[BOOL].tt_is_uinteger = false;
    109  1.321    rillig 		ttab[BOOL].tt_is_arithmetic = false;
    110  1.321    rillig 	}
    111   1.22     lukem 
    112  1.214    rillig 	/* struct, union, enum, ptr, array and func are not shared. */
    113  1.321    rillig 	for (int i = (int)SIGNED; i < (int)STRUCT; i++)
    114  1.321    rillig 		typetab[i].t_tspec = (tspec_t)i;
    115    1.1       cgd }
    116    1.1       cgd 
    117    1.1       cgd /*
    118   1.73    rillig  * Returns a shared type structure for arithmetic types and void.
    119    1.1       cgd  *
    120  1.247    rillig  * It's important to duplicate this structure using block_dup_type or
    121  1.247    rillig  * expr_dup_type if it is to be modified (adding qualifiers or anything
    122  1.169    rillig  * else).
    123    1.1       cgd  */
    124    1.1       cgd type_t *
    125   1.22     lukem gettyp(tspec_t t)
    126    1.1       cgd {
    127   1.22     lukem 
    128  1.172    rillig 	/* TODO: make the return type 'const' */
    129   1.76    rillig 	return &typetab[t];
    130    1.1       cgd }
    131    1.1       cgd 
    132    1.1       cgd type_t *
    133  1.247    rillig block_dup_type(const type_t *tp)
    134    1.1       cgd {
    135  1.316    rillig 	type_t *ntp;
    136    1.1       cgd 
    137  1.246    rillig 	ntp = block_zero_alloc(sizeof(*ntp));
    138   1.85    rillig 	*ntp = *tp;
    139   1.76    rillig 	return ntp;
    140    1.1       cgd }
    141    1.1       cgd 
    142  1.247    rillig /* Duplicate a type, free the allocated memory after the expression. */
    143    1.1       cgd type_t *
    144  1.169    rillig expr_dup_type(const type_t *tp)
    145    1.1       cgd {
    146  1.316    rillig 	type_t *ntp;
    147    1.1       cgd 
    148  1.246    rillig 	ntp = expr_zero_alloc(sizeof(*ntp));
    149   1.85    rillig 	*ntp = *tp;
    150   1.76    rillig 	return ntp;
    151    1.1       cgd }
    152    1.1       cgd 
    153    1.1       cgd /*
    154  1.211    rillig  * Return the unqualified version of the type.  The returned type is freed at
    155  1.211    rillig  * the end of the current expression.
    156  1.211    rillig  *
    157  1.211    rillig  * See C99 6.2.5p25.
    158  1.211    rillig  */
    159  1.211    rillig type_t *
    160  1.211    rillig expr_unqualified_type(const type_t *tp)
    161  1.211    rillig {
    162  1.211    rillig 	type_t *ntp;
    163  1.211    rillig 
    164  1.246    rillig 	ntp = expr_zero_alloc(sizeof(*ntp));
    165  1.211    rillig 	*ntp = *tp;
    166  1.211    rillig 	ntp->t_const = false;
    167  1.211    rillig 	ntp->t_volatile = false;
    168  1.211    rillig 
    169  1.221    rillig 	/*
    170  1.221    rillig 	 * In case of a struct or union type, the members should lose their
    171  1.221    rillig 	 * qualifiers as well, but that would require a deep copy of the
    172  1.221    rillig 	 * struct or union type.  This in turn would defeat the type
    173  1.298    rillig 	 * comparison in types_compatible, which simply tests whether
    174  1.308    rillig 	 * tp1->t_sou == tp2->t_sou.
    175  1.221    rillig 	 */
    176  1.211    rillig 
    177  1.211    rillig 	return ntp;
    178  1.211    rillig }
    179  1.211    rillig 
    180  1.211    rillig /*
    181  1.131    rillig  * Returns whether the argument is void or an incomplete array,
    182    1.1       cgd  * struct, union or enum type.
    183    1.1       cgd  */
    184  1.122    rillig bool
    185  1.132    rillig is_incomplete(const type_t *tp)
    186    1.1       cgd {
    187  1.316    rillig 	tspec_t t;
    188    1.1       cgd 
    189  1.298    rillig 	if ((t = tp->t_tspec) == VOID)
    190  1.124    rillig 		return true;
    191  1.298    rillig 	if (t == ARRAY)
    192  1.136    rillig 		return tp->t_incomplete_array;
    193  1.298    rillig 	if (is_struct_or_union(t))
    194  1.308    rillig 		return tp->t_sou->sou_incomplete;
    195  1.298    rillig 	if (t == ENUM)
    196  1.135    rillig 		return tp->t_enum->en_incomplete;
    197  1.298    rillig 
    198  1.124    rillig 	return false;
    199    1.1       cgd }
    200    1.1       cgd 
    201    1.1       cgd /*
    202  1.297    rillig  * Remember the storage class of the current declaration and detect multiple
    203    1.1       cgd  * storage classes.
    204    1.1       cgd  */
    205    1.1       cgd void
    206  1.296    rillig dcs_add_storage_class(scl_t sc)
    207    1.1       cgd {
    208   1.22     lukem 
    209    1.4       jpo 	if (sc == INLINE) {
    210    1.4       jpo 		if (dcs->d_inline)
    211    1.4       jpo 			/* duplicate '%s' */
    212    1.4       jpo 			warning(10, "inline");
    213  1.122    rillig 		dcs->d_inline = true;
    214    1.4       jpo 		return;
    215    1.4       jpo 	}
    216  1.298    rillig 
    217  1.311    rillig 	if (dcs->d_type != NULL || dcs->d_abstract_type != NO_TSPEC ||
    218  1.311    rillig 	    dcs->d_sign_mod != NO_TSPEC || dcs->d_rank_mod != NO_TSPEC) {
    219    1.1       cgd 		/* storage class after type is obsolescent */
    220    1.1       cgd 		warning(83);
    221    1.1       cgd 	}
    222  1.298    rillig 
    223  1.298    rillig 	if (dcs->d_scl == NOSCL)
    224    1.3       jpo 		dcs->d_scl = sc;
    225  1.298    rillig 	else
    226  1.209    rillig 		dcs->d_multiple_storage_classes = true;
    227    1.1       cgd }
    228    1.1       cgd 
    229    1.1       cgd /*
    230    1.1       cgd  * Remember the type, modifier or typedef name returned by the parser
    231    1.1       cgd  * in *dcs (top element of decl stack). This information is used in
    232  1.296    rillig  * dcs_end_type to build the type used for all declarators in this
    233    1.1       cgd  * declaration.
    234    1.1       cgd  *
    235  1.302    rillig  * If tp->t_typedef is true, the type comes from a previously defined
    236  1.302    rillig  * typename. Otherwise, it comes from a type specifier (int, long, ...) or a
    237    1.1       cgd  * struct/union/enum tag.
    238    1.1       cgd  */
    239    1.1       cgd void
    240  1.296    rillig dcs_add_type(type_t *tp)
    241    1.1       cgd {
    242  1.316    rillig 	tspec_t t;
    243  1.213    rillig 
    244  1.213    rillig 	debug_step("%s: %s", __func__, type_name(tp));
    245    1.1       cgd 	if (tp->t_typedef) {
    246   1.92    rillig 		/*
    247   1.92    rillig 		 * something like "typedef int a; int a b;"
    248   1.92    rillig 		 * This should not happen with current grammar.
    249   1.92    rillig 		 */
    250   1.92    rillig 		lint_assert(dcs->d_type == NULL);
    251  1.311    rillig 		lint_assert(dcs->d_abstract_type == NO_TSPEC);
    252  1.311    rillig 		lint_assert(dcs->d_sign_mod == NO_TSPEC);
    253  1.311    rillig 		lint_assert(dcs->d_rank_mod == NO_TSPEC);
    254   1.92    rillig 
    255    1.3       jpo 		dcs->d_type = tp;
    256    1.1       cgd 		return;
    257    1.1       cgd 	}
    258    1.1       cgd 
    259    1.1       cgd 	t = tp->t_tspec;
    260    1.1       cgd 
    261  1.292    rillig 	if (is_struct_or_union(t) || t == ENUM) {
    262    1.1       cgd 		/*
    263    1.1       cgd 		 * something like "int struct a ..."
    264    1.1       cgd 		 * struct/union/enum with anything else is not allowed
    265    1.1       cgd 		 */
    266  1.311    rillig 		if (dcs->d_type != NULL || dcs->d_abstract_type != NO_TSPEC ||
    267  1.311    rillig 		    dcs->d_rank_mod != NO_TSPEC || dcs->d_sign_mod != NO_TSPEC) {
    268  1.209    rillig 			dcs->d_invalid_type_combination = true;
    269  1.311    rillig 			dcs->d_abstract_type = NO_TSPEC;
    270  1.311    rillig 			dcs->d_sign_mod = NO_TSPEC;
    271  1.311    rillig 			dcs->d_rank_mod = NO_TSPEC;
    272    1.1       cgd 		}
    273    1.3       jpo 		dcs->d_type = tp;
    274    1.1       cgd 		return;
    275    1.1       cgd 	}
    276    1.1       cgd 
    277    1.3       jpo 	if (dcs->d_type != NULL && !dcs->d_type->t_typedef) {
    278    1.1       cgd 		/*
    279    1.1       cgd 		 * something like "struct a int"
    280    1.1       cgd 		 * struct/union/enum with anything else is not allowed
    281    1.1       cgd 		 */
    282  1.209    rillig 		dcs->d_invalid_type_combination = true;
    283    1.1       cgd 		return;
    284    1.1       cgd 	}
    285    1.1       cgd 
    286   1.39  christos 	if (t == COMPLEX) {
    287  1.147    rillig 		if (dcs->d_complex_mod == FLOAT)
    288   1.39  christos 			t = FCOMPLEX;
    289  1.147    rillig 		else if (dcs->d_complex_mod == DOUBLE)
    290   1.39  christos 			t = DCOMPLEX;
    291  1.100    rillig 		else {
    292  1.104    rillig 			/* invalid type for _Complex */
    293  1.100    rillig 			error(308);
    294  1.100    rillig 			t = DCOMPLEX; /* just as a fallback */
    295  1.100    rillig 		}
    296  1.311    rillig 		dcs->d_complex_mod = NO_TSPEC;
    297   1.39  christos 	}
    298   1.39  christos 
    299  1.147    rillig 	if (t == LONG && dcs->d_rank_mod == LONG) {
    300    1.1       cgd 		/* "long long" or "long ... long" */
    301    1.1       cgd 		t = QUAD;
    302  1.311    rillig 		dcs->d_rank_mod = NO_TSPEC;
    303    1.9       jpo 		if (!quadflg)
    304  1.243    rillig 			/* %s does not support 'long long' */
    305  1.279    rillig 			c99ism(265, allow_c90 ? "C90" : "traditional C");
    306    1.1       cgd 	}
    307    1.1       cgd 
    308    1.3       jpo 	if (dcs->d_type != NULL && dcs->d_type->t_typedef) {
    309    1.1       cgd 		/* something like "typedef int a; a long ..." */
    310  1.297    rillig 		dcs->d_type = typedef_error(dcs->d_type, t);
    311    1.1       cgd 		return;
    312    1.1       cgd 	}
    313    1.1       cgd 
    314    1.1       cgd 	/* now it can be only a combination of arithmetic types and void */
    315    1.1       cgd 	if (t == SIGNED || t == UNSIGN) {
    316  1.147    rillig 		/*
    317  1.147    rillig 		 * remember specifiers "signed" & "unsigned" in
    318  1.147    rillig 		 * dcs->d_sign_mod
    319  1.147    rillig 		 */
    320  1.311    rillig 		if (dcs->d_sign_mod != NO_TSPEC)
    321  1.209    rillig 			/* more than one "signed" and/or "unsigned" */
    322  1.209    rillig 			dcs->d_invalid_type_combination = true;
    323  1.147    rillig 		dcs->d_sign_mod = t;
    324    1.1       cgd 	} else if (t == SHORT || t == LONG || t == QUAD) {
    325    1.1       cgd 		/*
    326    1.1       cgd 		 * remember specifiers "short", "long" and "long long" in
    327  1.147    rillig 		 * dcs->d_rank_mod
    328    1.1       cgd 		 */
    329  1.311    rillig 		if (dcs->d_rank_mod != NO_TSPEC)
    330  1.209    rillig 			dcs->d_invalid_type_combination = true;
    331  1.147    rillig 		dcs->d_rank_mod = t;
    332   1.39  christos 	} else if (t == FLOAT || t == DOUBLE) {
    333  1.311    rillig 		if (dcs->d_rank_mod == NO_TSPEC || dcs->d_rank_mod == LONG) {
    334  1.311    rillig 			if (dcs->d_complex_mod != NO_TSPEC
    335  1.147    rillig 			    || (t == FLOAT && dcs->d_rank_mod == LONG))
    336  1.209    rillig 				dcs->d_invalid_type_combination = true;
    337  1.147    rillig 			dcs->d_complex_mod = t;
    338   1.40  christos 		} else {
    339  1.311    rillig 			if (dcs->d_abstract_type != NO_TSPEC)
    340  1.209    rillig 				dcs->d_invalid_type_combination = true;
    341  1.147    rillig 			dcs->d_abstract_type = t;
    342   1.40  christos 		}
    343   1.68  christos 	} else if (t == PTR) {
    344   1.68  christos 		dcs->d_type = tp;
    345    1.1       cgd 	} else {
    346    1.1       cgd 		/*
    347   1.39  christos 		 * remember specifiers "void", "char", "int",
    348  1.147    rillig 		 * or "_Complex" in dcs->d_abstract_type
    349    1.1       cgd 		 */
    350  1.311    rillig 		if (dcs->d_abstract_type != NO_TSPEC)
    351  1.209    rillig 			dcs->d_invalid_type_combination = true;
    352  1.147    rillig 		dcs->d_abstract_type = t;
    353    1.1       cgd 	}
    354    1.1       cgd }
    355    1.1       cgd 
    356  1.206    rillig /* Merge the signedness into the abstract type. */
    357  1.206    rillig static tspec_t
    358  1.206    rillig merge_signedness(tspec_t t, tspec_t s)
    359  1.206    rillig {
    360  1.206    rillig 
    361  1.207    rillig 	if (s == SIGNED)
    362  1.207    rillig 		return t == CHAR ? SCHAR : t;
    363  1.207    rillig 	if (s != UNSIGN)
    364  1.206    rillig 		return t;
    365  1.207    rillig 	return t == CHAR ? UCHAR
    366  1.207    rillig 	    : t == SHORT ? USHORT
    367  1.207    rillig 	    : t == INT ? UINT
    368  1.207    rillig 	    : t == LONG ? ULONG
    369  1.207    rillig 	    : t == QUAD ? UQUAD
    370  1.207    rillig 	    : t;
    371  1.206    rillig }
    372  1.206    rillig 
    373    1.1       cgd /*
    374    1.1       cgd  * called if a list of declaration specifiers contains a typedef name
    375    1.1       cgd  * and other specifiers (except struct, union, enum, typedef name)
    376    1.1       cgd  */
    377    1.1       cgd static type_t *
    378  1.297    rillig typedef_error(type_t *td, tspec_t t)
    379    1.1       cgd {
    380  1.316    rillig 	tspec_t t2;
    381    1.1       cgd 
    382    1.1       cgd 	t2 = td->t_tspec;
    383    1.1       cgd 
    384  1.233    rillig 	if ((t == SIGNED || t == UNSIGN) &&
    385  1.233    rillig 	    (t2 == CHAR || t2 == SHORT || t2 == INT ||
    386  1.233    rillig 	     t2 == LONG || t2 == QUAD)) {
    387  1.279    rillig 		if (allow_c90)
    388  1.233    rillig 			/* modifying typedef with '%s'; only qualifiers... */
    389  1.233    rillig 			warning(5, tspec_name(t));
    390  1.247    rillig 		td = block_dup_type(gettyp(merge_signedness(t2, t)));
    391  1.233    rillig 		td->t_typedef = true;
    392  1.233    rillig 		return td;
    393  1.233    rillig 	}
    394  1.233    rillig 
    395  1.233    rillig 	if (t == SHORT && (t2 == INT || t2 == UINT)) {
    396  1.233    rillig 		/* modifying typedef with '%s'; only qualifiers allowed */
    397  1.233    rillig 		warning(5, "short");
    398  1.247    rillig 		td = block_dup_type(gettyp(t2 == INT ? SHORT : USHORT));
    399  1.233    rillig 		td->t_typedef = true;
    400  1.233    rillig 		return td;
    401  1.233    rillig 	}
    402  1.233    rillig 
    403  1.298    rillig 	if (t != LONG)
    404  1.298    rillig 		goto invalid;
    405  1.298    rillig 
    406  1.298    rillig 	if (t2 == INT)
    407  1.298    rillig 		td = gettyp(LONG);
    408  1.298    rillig 	else if (t2 == UINT)
    409  1.298    rillig 		td = gettyp(ULONG);
    410  1.298    rillig 	else if (t2 == LONG)
    411  1.298    rillig 		td = gettyp(QUAD);
    412  1.298    rillig 	else if (t2 == ULONG)
    413  1.298    rillig 		td = gettyp(UQUAD);
    414  1.298    rillig 	else if (t2 == FLOAT)
    415  1.298    rillig 		td = gettyp(DOUBLE);
    416  1.298    rillig 	else if (t2 == DOUBLE)
    417  1.298    rillig 		td = gettyp(LDOUBLE);
    418  1.298    rillig 	else if (t2 == DCOMPLEX)
    419  1.298    rillig 		td = gettyp(LCOMPLEX);
    420  1.298    rillig 	else
    421  1.298    rillig 		goto invalid;
    422  1.298    rillig 
    423  1.298    rillig 	/* modifying typedef with '%s'; only qualifiers allowed */
    424  1.298    rillig 	warning(5, "long");
    425  1.298    rillig 	td = block_dup_type(td);
    426  1.298    rillig 	td->t_typedef = true;
    427  1.298    rillig 	return td;
    428    1.1       cgd 
    429  1.298    rillig invalid:
    430  1.233    rillig 	/* Anything else is not accepted. */
    431  1.209    rillig 	dcs->d_invalid_type_combination = true;
    432   1.76    rillig 	return td;
    433    1.1       cgd }
    434    1.1       cgd 
    435    1.1       cgd /*
    436    1.1       cgd  * Remember the symbol of a typedef name (2nd arg) in a struct, union
    437    1.1       cgd  * or enum tag if the typedef name is the first defined for this tag.
    438    1.1       cgd  *
    439  1.245    rillig  * If the tag is unnamed, the typedef name is used for identification
    440   1.86    rillig  * of this tag in lint2. Although it's possible that more than one typedef
    441    1.1       cgd  * name is defined for one tag, the first name defined should be unique
    442    1.1       cgd  * if the tag is unnamed.
    443    1.1       cgd  */
    444    1.1       cgd static void
    445  1.297    rillig set_first_typedef(type_t *tp, sym_t *sym)
    446    1.1       cgd {
    447  1.316    rillig 	tspec_t t;
    448    1.1       cgd 
    449  1.298    rillig 	if (is_struct_or_union(t = tp->t_tspec)) {
    450  1.308    rillig 		if (tp->t_sou->sou_first_typedef == NULL)
    451  1.308    rillig 			tp->t_sou->sou_first_typedef = sym;
    452    1.1       cgd 	} else if (t == ENUM) {
    453  1.135    rillig 		if (tp->t_enum->en_first_typedef == NULL)
    454  1.135    rillig 			tp->t_enum->en_first_typedef = sym;
    455    1.1       cgd 	}
    456    1.1       cgd }
    457    1.1       cgd 
    458  1.225    rillig static unsigned int
    459  1.322    rillig bit_field_width(sym_t **mem)
    460   1.65  christos {
    461  1.322    rillig 	unsigned int width = (*mem)->s_type->t_bit_field_width;
    462  1.122    rillig 	while (*mem != NULL && (*mem)->s_type->t_bitfield) {
    463  1.322    rillig 		width += (*mem)->s_type->t_bit_field_width;
    464   1.80    rillig 		*mem = (*mem)->s_next;
    465   1.65  christos 	}
    466  1.322    rillig 	// XXX: Why INT_SIZE? C99 6.7.2.1p4 allows bit-fields to have type
    467  1.322    rillig 	// XXX: _Bool or another implementation-defined type.
    468  1.322    rillig 	return width - width % INT_SIZE;
    469   1.65  christos }
    470   1.65  christos 
    471   1.48  christos static void
    472  1.297    rillig set_packed_size(type_t *tp)
    473   1.47  christos {
    474  1.134    rillig 	struct_or_union *sp;
    475   1.47  christos 	sym_t *mem;
    476   1.47  christos 
    477   1.47  christos 	switch (tp->t_tspec) {
    478   1.47  christos 	case STRUCT:
    479   1.47  christos 	case UNION:
    480  1.308    rillig 		sp = tp->t_sou;
    481  1.149    rillig 		sp->sou_size_in_bits = 0;
    482  1.134    rillig 		for (mem = sp->sou_first_member;
    483  1.134    rillig 		     mem != NULL; mem = mem->s_next) {
    484  1.242    rillig 			unsigned int x;
    485  1.242    rillig 
    486  1.108    rillig 			if (mem->s_type->t_bitfield) {
    487  1.322    rillig 				sp->sou_size_in_bits += bit_field_width(&mem);
    488   1.51  christos 				if (mem == NULL)
    489   1.51  christos 					break;
    490   1.51  christos 			}
    491  1.242    rillig 			x = type_size_in_bits(mem->s_type);
    492   1.51  christos 			if (tp->t_tspec == STRUCT)
    493  1.149    rillig 				sp->sou_size_in_bits += x;
    494  1.149    rillig 			else if (x > sp->sou_size_in_bits)
    495  1.149    rillig 				sp->sou_size_in_bits = x;
    496   1.47  christos 		}
    497   1.47  christos 		break;
    498   1.47  christos 	default:
    499  1.293    rillig 		/* attribute '%s' ignored for '%s' */
    500   1.98    rillig 		warning(326, "packed", type_name(tp));
    501   1.47  christos 		break;
    502   1.47  christos 	}
    503   1.47  christos }
    504   1.47  christos 
    505   1.48  christos void
    506  1.296    rillig dcs_add_packed(void)
    507   1.48  christos {
    508   1.49  christos 	if (dcs->d_type == NULL)
    509  1.122    rillig 		dcs->d_packed = true;
    510   1.49  christos 	else
    511  1.297    rillig 		set_packed_size(dcs->d_type);
    512   1.48  christos }
    513   1.48  christos 
    514   1.67  christos void
    515  1.296    rillig dcs_set_used(void)
    516   1.67  christos {
    517  1.122    rillig 	dcs->d_used = true;
    518   1.67  christos }
    519   1.67  christos 
    520    1.1       cgd /*
    521    1.1       cgd  * Remember a qualifier which is part of the declaration specifiers
    522  1.296    rillig  * (and not the declarator).
    523    1.1       cgd  * Also detect multiple qualifiers of the same kind.
    524    1.1       cgd 
    525  1.296    rillig  * The remembered qualifier is used by dcs_end_type to construct the type
    526    1.1       cgd  * for all declarators.
    527    1.1       cgd  */
    528    1.1       cgd void
    529  1.296    rillig dcs_add_qualifier(tqual_t q)
    530    1.1       cgd {
    531   1.22     lukem 
    532    1.1       cgd 	if (q == CONST) {
    533    1.3       jpo 		if (dcs->d_const) {
    534   1.88    rillig 			/* duplicate '%s' */
    535    1.1       cgd 			warning(10, "const");
    536    1.1       cgd 		}
    537  1.122    rillig 		dcs->d_const = true;
    538  1.128    rillig 	} else if (q == VOLATILE) {
    539    1.3       jpo 		if (dcs->d_volatile) {
    540   1.88    rillig 			/* duplicate '%s' */
    541    1.1       cgd 			warning(10, "volatile");
    542    1.1       cgd 		}
    543  1.122    rillig 		dcs->d_volatile = true;
    544  1.128    rillig 	} else {
    545  1.304    rillig 		lint_assert(q == RESTRICT || q == THREAD || q == ATOMIC);
    546  1.128    rillig 		/* Silently ignore these qualifiers. */
    547    1.1       cgd 	}
    548    1.1       cgd }
    549    1.1       cgd 
    550    1.1       cgd /*
    551    1.1       cgd  * Go to the next declaration level (structs, nested structs, blocks,
    552    1.1       cgd  * argument declaration lists ...)
    553    1.1       cgd  */
    554    1.1       cgd void
    555  1.276    rillig begin_declaration_level(declaration_kind dk)
    556    1.1       cgd {
    557  1.316    rillig 	dinfo_t *di;
    558    1.1       cgd 
    559    1.1       cgd 	/* put a new element on the declaration stack */
    560  1.170    rillig 	di = xcalloc(1, sizeof(*di));
    561  1.259    rillig 	di->d_enclosing = dcs;
    562    1.1       cgd 	dcs = di;
    563  1.276    rillig 	di->d_kind = dk;
    564    1.3       jpo 	di->d_ldlsym = &di->d_dlsyms;
    565  1.276    rillig 	debug_step("%s(%s)", __func__, declaration_kind_name(dk));
    566    1.1       cgd }
    567    1.1       cgd 
    568    1.1       cgd /*
    569    1.1       cgd  * Go back to previous declaration level
    570    1.1       cgd  */
    571    1.1       cgd void
    572  1.160    rillig end_declaration_level(void)
    573    1.1       cgd {
    574  1.316    rillig 	dinfo_t *di;
    575    1.1       cgd 
    576  1.276    rillig 	debug_step("%s(%s)", __func__, declaration_kind_name(dcs->d_kind));
    577    1.1       cgd 
    578  1.259    rillig 	lint_assert(dcs->d_enclosing != NULL);
    579    1.1       cgd 	di = dcs;
    580  1.259    rillig 	dcs = di->d_enclosing;
    581  1.302    rillig 
    582  1.276    rillig 	switch (di->d_kind) {
    583  1.303    rillig 	case DK_STRUCT_MEMBER:
    584  1.303    rillig 	case DK_UNION_MEMBER:
    585  1.303    rillig 	case DK_ENUM_CONSTANT:
    586    1.1       cgd 		/*
    587    1.1       cgd 		 * Symbols declared in (nested) structs or enums are
    588    1.1       cgd 		 * part of the next level (they are removed from the
    589  1.123    rillig 		 * symbol table if the symbols of the outer level are
    590   1.73    rillig 		 * removed).
    591    1.1       cgd 		 */
    592    1.3       jpo 		if ((*dcs->d_ldlsym = di->d_dlsyms) != NULL)
    593    1.3       jpo 			dcs->d_ldlsym = di->d_ldlsym;
    594    1.1       cgd 		break;
    595  1.276    rillig 	case DK_OLD_STYLE_ARG:
    596    1.1       cgd 		/*
    597  1.300    rillig 		 * All symbols in dcs->d_dlsyms are introduced in old-style
    598    1.1       cgd 		 * argument declarations (it's not clean, but possible).
    599    1.1       cgd 		 * They are appended to the list of symbols declared in
    600  1.300    rillig 		 * an old-style argument identifier list or a new style
    601    1.1       cgd 		 * parameter type list.
    602    1.1       cgd 		 */
    603    1.3       jpo 		if (di->d_dlsyms != NULL) {
    604  1.156    rillig 			*di->d_ldlsym = dcs->d_func_proto_syms;
    605  1.156    rillig 			dcs->d_func_proto_syms = di->d_dlsyms;
    606    1.1       cgd 		}
    607    1.1       cgd 		break;
    608  1.298    rillig 	case DK_ABSTRACT:	/* casts and sizeof */
    609    1.1       cgd 		/*
    610    1.1       cgd 		 * Append all symbols declared in the abstract declaration
    611   1.73    rillig 		 * to the list of symbols declared in the surrounding
    612   1.73    rillig 		 * declaration or block.
    613    1.1       cgd 		 * XXX I'm not sure whether they should be removed from the
    614    1.1       cgd 		 * symbol table now or later.
    615    1.1       cgd 		 */
    616    1.3       jpo 		if ((*dcs->d_ldlsym = di->d_dlsyms) != NULL)
    617    1.3       jpo 			dcs->d_ldlsym = di->d_ldlsym;
    618    1.1       cgd 		break;
    619  1.276    rillig 	case DK_AUTO:
    620    1.1       cgd 		/* check usage of local vars */
    621   1.75    rillig 		check_usage(di);
    622    1.1       cgd 		/* FALLTHROUGH */
    623  1.276    rillig 	case DK_PROTO_ARG:
    624  1.305    rillig 		/* usage of arguments will be checked by end_function() */
    625    1.3       jpo 		rmsyms(di->d_dlsyms);
    626    1.1       cgd 		break;
    627  1.276    rillig 	case DK_EXTERN:
    628  1.302    rillig 		/* there is nothing around an external declarations */
    629   1.97    rillig 		/* FALLTHROUGH */
    630    1.1       cgd 	default:
    631  1.124    rillig 		lint_assert(/*CONSTCOND*/false);
    632    1.1       cgd 	}
    633    1.1       cgd 	free(di);
    634    1.1       cgd }
    635    1.1       cgd 
    636    1.1       cgd /*
    637   1.10       jpo  * Set flag d_asm in all declaration stack elements up to the
    638   1.10       jpo  * outermost one.
    639   1.10       jpo  *
    640   1.10       jpo  * This is used to mark compound statements which have, possibly in
    641   1.10       jpo  * nested compound statements, asm statements. For these compound
    642  1.111    rillig  * statements no warnings about unused or uninitialized variables are
    643   1.10       jpo  * printed.
    644   1.10       jpo  *
    645   1.10       jpo  * There is no need to clear d_asm in dinfo structs with context AUTO,
    646   1.10       jpo  * because these structs are freed at the end of the compound statement.
    647   1.62  dholland  * But it must be cleared in the outermost dinfo struct, which has
    648  1.296    rillig  * context EXTERN. This could be done in dcs_begin_type and would work for
    649  1.296    rillig  * C90, but not for C99 or C++ (due to mixed statements and declarations).
    650  1.296    rillig  * Thus we clear it in global_clean_up_decl(), which is used to do some
    651  1.296    rillig  * cleanup after global declarations/definitions.
    652   1.10       jpo  */
    653   1.10       jpo void
    654  1.296    rillig dcs_set_asm(void)
    655   1.10       jpo {
    656   1.10       jpo 
    657  1.298    rillig 	for (dinfo_t *di = dcs; di != NULL; di = di->d_enclosing)
    658  1.122    rillig 		di->d_asm = true;
    659   1.10       jpo }
    660   1.10       jpo 
    661   1.10       jpo /*
    662    1.1       cgd  * Clean all elements of the top element of declaration stack which
    663    1.1       cgd  * will be used by the next declaration
    664    1.1       cgd  */
    665    1.1       cgd void
    666  1.296    rillig dcs_begin_type(void)
    667    1.1       cgd {
    668   1.22     lukem 
    669  1.311    rillig 	dcs->d_abstract_type = NO_TSPEC;
    670  1.311    rillig 	dcs->d_complex_mod = NO_TSPEC;
    671  1.311    rillig 	dcs->d_sign_mod = NO_TSPEC;
    672  1.311    rillig 	dcs->d_rank_mod = NO_TSPEC;
    673    1.3       jpo 	dcs->d_scl = NOSCL;
    674    1.3       jpo 	dcs->d_type = NULL;
    675  1.122    rillig 	dcs->d_const = false;
    676  1.122    rillig 	dcs->d_volatile = false;
    677  1.122    rillig 	dcs->d_inline = false;
    678  1.209    rillig 	dcs->d_multiple_storage_classes = false;
    679  1.209    rillig 	dcs->d_invalid_type_combination = false;
    680  1.155    rillig 	dcs->d_nonempty_decl = false;
    681  1.122    rillig 	dcs->d_notyp = false;
    682    1.1       cgd }
    683    1.1       cgd 
    684  1.150    rillig static void
    685  1.150    rillig dcs_adjust_storage_class(void)
    686  1.150    rillig {
    687  1.276    rillig 	if (dcs->d_kind == DK_EXTERN) {
    688  1.150    rillig 		if (dcs->d_scl == REG || dcs->d_scl == AUTO) {
    689  1.150    rillig 			/* illegal storage class */
    690  1.150    rillig 			error(8);
    691  1.150    rillig 			dcs->d_scl = NOSCL;
    692  1.150    rillig 		}
    693  1.276    rillig 	} else if (dcs->d_kind == DK_OLD_STYLE_ARG ||
    694  1.276    rillig 		   dcs->d_kind == DK_PROTO_ARG) {
    695  1.150    rillig 		if (dcs->d_scl != NOSCL && dcs->d_scl != REG) {
    696  1.150    rillig 			/* only register valid as formal parameter storage... */
    697  1.150    rillig 			error(9);
    698  1.150    rillig 			dcs->d_scl = NOSCL;
    699  1.150    rillig 		}
    700  1.150    rillig 	}
    701  1.150    rillig }
    702  1.150    rillig 
    703  1.205    rillig /*
    704  1.205    rillig  * Merge the declaration specifiers from dcs into dcs->d_type.
    705  1.205    rillig  *
    706  1.205    rillig  * See C99 6.7.2 "Type specifiers".
    707  1.205    rillig  */
    708  1.204    rillig static void
    709  1.204    rillig dcs_merge_declaration_specifiers(void)
    710    1.1       cgd {
    711  1.316    rillig 	tspec_t t, s, l, c;
    712  1.316    rillig 	type_t *tp;
    713    1.1       cgd 
    714  1.147    rillig 	t = dcs->d_abstract_type; /* VOID, BOOL, CHAR, INT or COMPLEX */
    715  1.147    rillig 	c = dcs->d_complex_mod;	/* FLOAT or DOUBLE */
    716  1.147    rillig 	s = dcs->d_sign_mod;	/* SIGNED or UNSIGN */
    717  1.147    rillig 	l = dcs->d_rank_mod;	/* SHORT, LONG or QUAD */
    718    1.3       jpo 	tp = dcs->d_type;
    719    1.1       cgd 
    720  1.213    rillig 	debug_step("%s: %s", __func__, type_name(tp));
    721  1.311    rillig 	if (t == NO_TSPEC && s == NO_TSPEC && l == NO_TSPEC && c == NO_TSPEC &&
    722   1.39  christos 	    tp == NULL)
    723  1.122    rillig 		dcs->d_notyp = true;
    724  1.311    rillig 	if (t == NO_TSPEC && s == NO_TSPEC && (l == NO_TSPEC || l == LONG) &&
    725   1.43  dholland 	    tp == NULL)
    726   1.39  christos 		t = c;
    727    1.1       cgd 
    728   1.92    rillig 	if (tp != NULL) {
    729  1.311    rillig 		lint_assert(t == NO_TSPEC);
    730  1.311    rillig 		lint_assert(s == NO_TSPEC);
    731  1.311    rillig 		lint_assert(l == NO_TSPEC);
    732  1.204    rillig 		return;
    733    1.1       cgd 	}
    734    1.1       cgd 
    735  1.311    rillig 	if (t == NO_TSPEC)
    736  1.204    rillig 		t = INT;
    737  1.311    rillig 	if (s == NO_TSPEC && t == INT)
    738  1.205    rillig 		s = SIGNED;
    739  1.311    rillig 	if (l != NO_TSPEC && t == CHAR) {
    740  1.209    rillig 		dcs->d_invalid_type_combination = true;
    741  1.311    rillig 		l = NO_TSPEC;
    742  1.205    rillig 	}
    743  1.205    rillig 	if (l == LONG && t == FLOAT) {
    744  1.311    rillig 		l = NO_TSPEC;
    745  1.205    rillig 		t = DOUBLE;
    746  1.279    rillig 		if (allow_c90)
    747  1.205    rillig 			/* use 'double' instead of 'long float' */
    748  1.205    rillig 			warning(6);
    749  1.205    rillig 	}
    750  1.205    rillig 	if ((l == LONG && t == DOUBLE) || t == LDOUBLE) {
    751  1.311    rillig 		l = NO_TSPEC;
    752  1.204    rillig 		t = LDOUBLE;
    753  1.204    rillig 	}
    754  1.279    rillig 	if (t == LDOUBLE && !allow_c90) {
    755  1.205    rillig 		/* 'long double' is illegal in traditional C */
    756  1.205    rillig 		warning(266);
    757  1.205    rillig 	}
    758  1.205    rillig 	if (l == LONG && t == DCOMPLEX) {
    759  1.311    rillig 		l = NO_TSPEC;
    760  1.205    rillig 		t = LCOMPLEX;
    761  1.205    rillig 	}
    762  1.205    rillig 
    763  1.311    rillig 	if (t != INT && t != CHAR && (s != NO_TSPEC || l != NO_TSPEC)) {
    764  1.209    rillig 		dcs->d_invalid_type_combination = true;
    765  1.311    rillig 		l = s = NO_TSPEC;
    766    1.1       cgd 	}
    767  1.311    rillig 	if (l != NO_TSPEC)
    768  1.204    rillig 		t = l;
    769  1.206    rillig 	dcs->d_type = gettyp(merge_signedness(t, s));
    770  1.204    rillig }
    771  1.204    rillig 
    772  1.204    rillig /*
    773  1.298    rillig  * Create a type structure from the information gathered in the declaration
    774  1.298    rillig  * stack.
    775  1.298    rillig  * Complain about storage classes which are not possible in current context.
    776  1.204    rillig  */
    777  1.204    rillig void
    778  1.296    rillig dcs_end_type(void)
    779  1.204    rillig {
    780  1.204    rillig 
    781  1.204    rillig 	dcs_merge_declaration_specifiers();
    782    1.1       cgd 
    783  1.209    rillig 	if (dcs->d_multiple_storage_classes) {
    784    1.1       cgd 		/* only one storage class allowed */
    785    1.1       cgd 		error(7);
    786    1.1       cgd 	}
    787  1.209    rillig 	if (dcs->d_invalid_type_combination) {
    788    1.1       cgd 		/* illegal type combination */
    789    1.1       cgd 		error(4);
    790    1.1       cgd 	}
    791    1.1       cgd 
    792  1.150    rillig 	dcs_adjust_storage_class();
    793    1.1       cgd 
    794  1.277    rillig 	if (dcs->d_const && dcs->d_type->t_const && !dcs->d_type->t_typeof) {
    795   1.92    rillig 		lint_assert(dcs->d_type->t_typedef);
    796   1.88    rillig 		/* typedef already qualified with '%s' */
    797    1.1       cgd 		warning(68, "const");
    798    1.1       cgd 	}
    799  1.277    rillig 	if (dcs->d_volatile && dcs->d_type->t_volatile &&
    800  1.277    rillig 	    !dcs->d_type->t_typeof) {
    801   1.92    rillig 		lint_assert(dcs->d_type->t_typedef);
    802   1.88    rillig 		/* typedef already qualified with '%s' */
    803    1.1       cgd 		warning(68, "volatile");
    804    1.1       cgd 	}
    805    1.1       cgd 
    806    1.3       jpo 	if (dcs->d_const || dcs->d_volatile) {
    807  1.247    rillig 		dcs->d_type = block_dup_type(dcs->d_type);
    808    1.3       jpo 		dcs->d_type->t_const |= dcs->d_const;
    809    1.3       jpo 		dcs->d_type->t_volatile |= dcs->d_volatile;
    810    1.1       cgd 	}
    811    1.1       cgd }
    812    1.1       cgd 
    813    1.1       cgd /*
    814   1.73    rillig  * Return the length of a type in bits.
    815    1.1       cgd  *
    816  1.111    rillig  * Printing a message if the outermost dimension of an array is 0 must
    817  1.270    rillig  * be done by the caller. All other problems are reported by this function
    818    1.1       cgd  * if name is not NULL.
    819    1.1       cgd  */
    820    1.1       cgd int
    821  1.270    rillig length_in_bits(const type_t *tp, const char *name)
    822    1.1       cgd {
    823  1.232    rillig 	unsigned int elem, elsz;
    824    1.1       cgd 
    825    1.1       cgd 	elem = 1;
    826  1.122    rillig 	while (tp != NULL && tp->t_tspec == ARRAY) {
    827    1.1       cgd 		elem *= tp->t_dim;
    828    1.1       cgd 		tp = tp->t_subt;
    829    1.1       cgd 	}
    830   1.18  christos 	if (tp == NULL)
    831   1.18  christos 		return -1;
    832   1.18  christos 
    833    1.1       cgd 	switch (tp->t_tspec) {
    834    1.1       cgd 	case FUNC:
    835  1.287    rillig 		lint_assert(/*CONSTCOND*/ false);
    836  1.287    rillig 		break;		/* GCC 10 thinks this were reachable */
    837    1.1       cgd 		/* NOTREACHED */
    838    1.1       cgd 	case STRUCT:
    839    1.1       cgd 	case UNION:
    840  1.132    rillig 		if (is_incomplete(tp) && name != NULL) {
    841  1.199    rillig 			/* '%s' has incomplete type '%s' */
    842  1.193    rillig 			error(31, name, type_name(tp));
    843    1.1       cgd 		}
    844  1.308    rillig 		elsz = tp->t_sou->sou_size_in_bits;
    845    1.1       cgd 		break;
    846    1.1       cgd 	case ENUM:
    847  1.132    rillig 		if (is_incomplete(tp) && name != NULL) {
    848  1.285    rillig 			/* incomplete enum type '%s' */
    849    1.1       cgd 			warning(13, name);
    850    1.1       cgd 		}
    851    1.1       cgd 		/* FALLTHROUGH */
    852    1.1       cgd 	default:
    853  1.143    rillig 		elsz = size_in_bits(tp->t_tspec);
    854  1.268    rillig 		/*
    855  1.268    rillig 		 * Workaround until the type parser (see add_function,
    856  1.268    rillig 		 * add_array, add_pointer) does not construct the invalid
    857  1.268    rillig 		 * intermediate declaration 'void b[4]' for the legitimate
    858  1.268    rillig 		 * declaration 'void *b[4]'.
    859  1.268    rillig 		 */
    860  1.268    rillig 		if (sytxerr > 0 && elsz == 0)
    861  1.268    rillig 			elsz = CHAR_SIZE;
    862  1.234    rillig 		lint_assert(elsz > 0);
    863    1.1       cgd 		break;
    864    1.1       cgd 	}
    865  1.232    rillig 	return (int)(elem * elsz);
    866    1.1       cgd }
    867    1.1       cgd 
    868  1.225    rillig unsigned int
    869  1.139    rillig alignment_in_bits(const type_t *tp)
    870    1.1       cgd {
    871  1.234    rillig 	unsigned int a;
    872  1.234    rillig 	tspec_t t;
    873    1.1       cgd 
    874  1.266    rillig 	/* Super conservative so that it works for most systems. */
    875  1.266    rillig 	unsigned int worst_align_in_bits = 2 * LONG_SIZE;
    876  1.266    rillig 
    877  1.223    rillig 	while (tp->t_tspec == ARRAY)
    878    1.1       cgd 		tp = tp->t_subt;
    879    1.1       cgd 
    880  1.298    rillig 	if (is_struct_or_union(t = tp->t_tspec))
    881  1.308    rillig 		a = tp->t_sou->sou_align_in_bits;
    882  1.298    rillig 	else {
    883  1.265    rillig 		lint_assert(t != FUNC);
    884  1.298    rillig 		if ((a = size_in_bits(t)) == 0)
    885  1.113    rillig 			a = CHAR_SIZE;
    886  1.298    rillig 		else if (a > worst_align_in_bits)
    887  1.266    rillig 			a = worst_align_in_bits;
    888  1.298    rillig 
    889    1.1       cgd 	}
    890  1.113    rillig 	lint_assert(a >= CHAR_SIZE);
    891  1.266    rillig 	lint_assert(a <= worst_align_in_bits);
    892   1.76    rillig 	return a;
    893    1.1       cgd }
    894    1.1       cgd 
    895    1.1       cgd /*
    896   1.80    rillig  * Concatenate two lists of symbols by s_next. Used by declarations of
    897    1.1       cgd  * struct/union/enum elements and parameters.
    898    1.1       cgd  */
    899    1.1       cgd sym_t *
    900  1.297    rillig concat_lists(sym_t *l1, sym_t *l2)
    901    1.1       cgd {
    902  1.316    rillig 	sym_t *l;
    903    1.1       cgd 
    904    1.1       cgd 	if ((l = l1) == NULL)
    905   1.76    rillig 		return l2;
    906   1.80    rillig 	while (l1->s_next != NULL)
    907   1.80    rillig 		l1 = l1->s_next;
    908   1.80    rillig 	l1->s_next = l2;
    909   1.76    rillig 	return l;
    910    1.1       cgd }
    911    1.1       cgd 
    912    1.1       cgd /*
    913    1.1       cgd  * Check if the type of the given symbol is valid and print an error
    914    1.1       cgd  * message if it is not.
    915    1.1       cgd  *
    916    1.1       cgd  * Invalid types are:
    917  1.111    rillig  * - arrays of incomplete types or functions
    918    1.1       cgd  * - functions returning arrays or functions
    919    1.1       cgd  * - void types other than type of function or pointer
    920    1.1       cgd  */
    921    1.1       cgd void
    922   1.75    rillig check_type(sym_t *sym)
    923    1.1       cgd {
    924  1.316    rillig 	tspec_t to, t;
    925  1.316    rillig 	type_t **tpp, *tp;
    926    1.1       cgd 
    927    1.1       cgd 	tpp = &sym->s_type;
    928  1.311    rillig 	to = NO_TSPEC;
    929    1.1       cgd 	while ((tp = *tpp) != NULL) {
    930    1.1       cgd 		t = tp->t_tspec;
    931    1.1       cgd 		/*
    932  1.300    rillig 		 * If this is the type of an old-style function definition,
    933  1.305    rillig 		 * a better warning is printed in begin_function().
    934    1.1       cgd 		 */
    935    1.1       cgd 		if (t == FUNC && !tp->t_proto &&
    936  1.311    rillig 		    !(to == NO_TSPEC && sym->s_osdef)) {
    937  1.280    rillig 			/* TODO: Make this an error in C99 mode as well. */
    938  1.280    rillig 			if ((!allow_trad && !allow_c99) && hflag)
    939    1.1       cgd 				/* function declaration is not a prototype */
    940    1.1       cgd 				warning(287);
    941    1.1       cgd 		}
    942    1.1       cgd 		if (to == FUNC) {
    943    1.1       cgd 			if (t == FUNC || t == ARRAY) {
    944  1.256    rillig 				/* function returns illegal type '%s' */
    945  1.256    rillig 				error(15, type_name(tp));
    946  1.298    rillig 				*tpp = block_derive_type(
    947  1.298    rillig 				    t == FUNC ? *tpp : (*tpp)->t_subt, PTR);
    948    1.1       cgd 				return;
    949  1.298    rillig 			}
    950  1.298    rillig 			if (tp->t_const || tp->t_volatile) {
    951  1.280    rillig 				/* TODO: Make this a warning in C99 mode as well. */
    952  1.280    rillig 				if (!allow_trad && !allow_c99) {	/* XXX or better allow_c90? */
    953    1.1       cgd 					/* function cannot return const... */
    954    1.1       cgd 					warning(228);
    955    1.1       cgd 				}
    956    1.1       cgd 			}
    957  1.254    rillig 		} else if (to == ARRAY) {
    958    1.1       cgd 			if (t == FUNC) {
    959    1.1       cgd 				/* array of function is illegal */
    960    1.1       cgd 				error(16);
    961    1.1       cgd 				*tpp = gettyp(INT);
    962    1.1       cgd 				return;
    963  1.298    rillig 			}
    964  1.298    rillig 			if (t == ARRAY && tp->t_dim == 0) {
    965    1.1       cgd 				/* null dimension */
    966    1.1       cgd 				error(17);
    967    1.1       cgd 				return;
    968  1.298    rillig 			}
    969  1.298    rillig 			if (t == VOID) {
    970   1.88    rillig 				/* illegal use of 'void' */
    971    1.1       cgd 				error(18);
    972    1.1       cgd 				*tpp = gettyp(INT);
    973    1.1       cgd 			}
    974  1.298    rillig 			/*
    975  1.298    rillig 			 * No need to check for incomplete types here as
    976  1.298    rillig 			 * length_in_bits already does this.
    977  1.298    rillig 			 */
    978  1.311    rillig 		} else if (to == NO_TSPEC && t == VOID) {
    979  1.276    rillig 			if (dcs->d_kind == DK_PROTO_ARG) {
    980    1.1       cgd 				if (sym->s_scl != ABSTRACT) {
    981   1.92    rillig 					lint_assert(sym->s_name != unnamed);
    982  1.290    rillig 					/* void parameter '%s' cannot ... */
    983    1.1       cgd 					error(61, sym->s_name);
    984    1.1       cgd 					*tpp = gettyp(INT);
    985    1.1       cgd 				}
    986  1.276    rillig 			} else if (dcs->d_kind == DK_ABSTRACT) {
    987    1.1       cgd 				/* ok */
    988    1.1       cgd 			} else if (sym->s_scl != TYPEDEF) {
    989  1.133    rillig 				/* void type for '%s' */
    990    1.1       cgd 				error(19, sym->s_name);
    991    1.1       cgd 				*tpp = gettyp(INT);
    992    1.1       cgd 			}
    993    1.1       cgd 		}
    994    1.1       cgd 		if (t == VOID && to != PTR) {
    995    1.1       cgd 			if (tp->t_const || tp->t_volatile) {
    996   1.88    rillig 				/* inappropriate qualifiers with 'void' */
    997    1.1       cgd 				warning(69);
    998  1.122    rillig 				tp->t_const = tp->t_volatile = false;
    999    1.1       cgd 			}
   1000    1.1       cgd 		}
   1001    1.1       cgd 		tpp = &tp->t_subt;
   1002    1.1       cgd 		to = t;
   1003    1.1       cgd 	}
   1004    1.1       cgd }
   1005    1.1       cgd 
   1006  1.142    rillig /*
   1007  1.142    rillig  * In traditional C, the only portable type for bit-fields is unsigned int.
   1008  1.142    rillig  *
   1009  1.142    rillig  * In C90, the only allowed types for bit-fields are int, signed int and
   1010  1.142    rillig  * unsigned int (3.5.2.1).  There is no mention of implementation-defined
   1011  1.142    rillig  * types.
   1012  1.142    rillig  *
   1013  1.142    rillig  * In C99, the only portable types for bit-fields are _Bool, signed int and
   1014  1.142    rillig  * unsigned int (6.7.2.1p4).  In addition, C99 allows "or some other
   1015  1.142    rillig  * implementation-defined type".
   1016  1.142    rillig  */
   1017  1.141    rillig static void
   1018  1.254    rillig check_bit_field_type(sym_t *dsym, type_t **const inout_tp, tspec_t *inout_t)
   1019  1.141    rillig {
   1020  1.179    rillig 	type_t *tp = *inout_tp;
   1021  1.141    rillig 	tspec_t t = *inout_t;
   1022  1.141    rillig 
   1023  1.141    rillig 	if (t == CHAR || t == UCHAR || t == SCHAR ||
   1024  1.141    rillig 	    t == SHORT || t == USHORT || t == ENUM) {
   1025  1.141    rillig 		if (!bitfieldtype_ok) {
   1026  1.280    rillig 			/* TODO: Make this an error in C99 mode as well. */
   1027  1.280    rillig 			if (!allow_trad && !allow_c99) {
   1028  1.294    rillig 				type_t *btp = block_dup_type(tp);
   1029  1.294    rillig 				btp->t_bitfield = false;
   1030  1.141    rillig 				/* bit-field type '%s' invalid in ANSI C */
   1031  1.294    rillig 				warning(273, type_name(btp));
   1032  1.141    rillig 			} else if (pflag) {
   1033  1.294    rillig 				type_t *btp = block_dup_type(tp);
   1034  1.294    rillig 				btp->t_bitfield = false;
   1035  1.181    rillig 				/* nonportable bit-field type '%s' */
   1036  1.294    rillig 				warning(34, type_name(btp));
   1037  1.141    rillig 			}
   1038  1.141    rillig 		}
   1039  1.311    rillig 	} else if (t == INT && dcs->d_sign_mod == NO_TSPEC) {
   1040  1.141    rillig 		if (pflag && !bitfieldtype_ok) {
   1041  1.182    rillig 			/* bit-field of type plain 'int' has ... */
   1042  1.182    rillig 			warning(344);
   1043  1.141    rillig 		}
   1044  1.278    rillig 	} else if (!(t == INT || t == UINT || t == BOOL ||
   1045  1.278    rillig 		     (is_integer(t) && (bitfieldtype_ok || allow_gcc)))) {
   1046  1.278    rillig 
   1047  1.294    rillig 		type_t *btp = block_dup_type(tp);
   1048  1.294    rillig 		btp->t_bitfield = false;
   1049  1.278    rillig 		/* illegal bit-field type '%s' */
   1050  1.294    rillig 		warning(35, type_name(btp));
   1051  1.278    rillig 
   1052  1.322    rillig 		// XXX: What about _Bool bit-fields since C99 6.7.2.1?
   1053  1.322    rillig 		unsigned int width = tp->t_bit_field_width;
   1054  1.278    rillig 		dsym->s_type = tp = block_dup_type(gettyp(t = INT));
   1055  1.322    rillig 		if ((tp->t_bit_field_width = width) > size_in_bits(t))
   1056  1.322    rillig 			tp->t_bit_field_width = size_in_bits(t);
   1057  1.278    rillig 		*inout_t = t;
   1058  1.278    rillig 		*inout_tp = tp;
   1059  1.141    rillig 	}
   1060  1.179    rillig }
   1061  1.179    rillig 
   1062  1.179    rillig static void
   1063  1.179    rillig declare_bit_field(sym_t *dsym, tspec_t *inout_t, type_t **const inout_tp)
   1064  1.179    rillig {
   1065  1.141    rillig 
   1066  1.179    rillig 	check_bit_field_type(dsym, inout_tp, inout_t);
   1067  1.179    rillig 
   1068  1.322    rillig 	type_t *tp = *inout_tp;
   1069  1.322    rillig 	tspec_t t = *inout_t;
   1070  1.322    rillig 	unsigned int t_width = size_in_bits(t);
   1071  1.322    rillig 	if (tp->t_bit_field_width > t_width) {
   1072  1.141    rillig 		/* illegal bit-field size: %d */
   1073  1.322    rillig 		error(36, (int)tp->t_bit_field_width);
   1074  1.322    rillig 		tp->t_bit_field_width = t_width;
   1075  1.322    rillig 	} else if (tp->t_bit_field_width == 0 && dsym->s_name != unnamed) {
   1076  1.141    rillig 		/* zero size bit-field */
   1077  1.141    rillig 		error(37);
   1078  1.322    rillig 		tp->t_bit_field_width = t_width;
   1079  1.141    rillig 	}
   1080  1.303    rillig 	if (dsym->s_scl == UNION_MEMBER) {
   1081  1.244    rillig 		/* bit-field in union is very unusual */
   1082  1.241  christos 		warning(41);
   1083  1.141    rillig 		dsym->s_type->t_bitfield = false;
   1084  1.141    rillig 		dsym->s_bitfield = false;
   1085  1.141    rillig 	}
   1086  1.141    rillig }
   1087  1.141    rillig 
   1088    1.1       cgd sym_t *
   1089  1.320    rillig declare_member(sym_t *dsym)
   1090    1.1       cgd {
   1091  1.316    rillig 	type_t *tp;
   1092  1.316    rillig 	tspec_t t;
   1093  1.316    rillig 	int sz;
   1094  1.224    rillig 	unsigned int o = 0;	/* Appease GCC */
   1095    1.1       cgd 
   1096  1.274    rillig 	lint_assert(is_member(dsym));
   1097    1.1       cgd 
   1098  1.154    rillig 	if (dcs->d_redeclared_symbol != NULL) {
   1099  1.274    rillig 		lint_assert(is_member(dcs->d_redeclared_symbol));
   1100  1.153    rillig 
   1101  1.273    rillig 		if (dsym->u.s_member.sm_sou_type ==
   1102  1.273    rillig 		    dcs->d_redeclared_symbol->u.s_member.sm_sou_type) {
   1103  1.289    rillig 			/* duplicate member name '%s' */
   1104    1.1       cgd 			error(33, dsym->s_name);
   1105  1.154    rillig 			rmsym(dcs->d_redeclared_symbol);
   1106    1.1       cgd 		}
   1107    1.1       cgd 	}
   1108    1.1       cgd 
   1109   1.75    rillig 	check_type(dsym);
   1110    1.1       cgd 
   1111    1.1       cgd 	t = (tp = dsym->s_type)->t_tspec;
   1112    1.1       cgd 
   1113  1.298    rillig 	if (dsym->s_bitfield)
   1114  1.141    rillig 		declare_bit_field(dsym, &t, &tp);
   1115  1.298    rillig 	else if (t == FUNC) {
   1116    1.1       cgd 		/* function illegal in structure or union */
   1117    1.1       cgd 		error(38);
   1118  1.247    rillig 		dsym->s_type = tp = block_derive_type(tp, t = PTR);
   1119    1.1       cgd 	}
   1120    1.1       cgd 
   1121    1.1       cgd 	/*
   1122  1.270    rillig 	 * bit-fields of length 0 are not warned about because length_in_bits
   1123    1.1       cgd 	 * does not return the length of the bit-field but the length
   1124   1.86    rillig 	 * of the type the bit-field is packed in (it's ok)
   1125    1.1       cgd 	 */
   1126  1.270    rillig 	if ((sz = length_in_bits(dsym->s_type, dsym->s_name)) == 0) {
   1127   1.36  christos 		if (t == ARRAY && dsym->s_type->t_dim == 0) {
   1128  1.290    rillig 			/* zero-sized array '%s' in struct is a C99 extension */
   1129   1.36  christos 			c99ism(39, dsym->s_name);
   1130    1.1       cgd 		}
   1131    1.1       cgd 	}
   1132    1.1       cgd 
   1133  1.303    rillig 	if (dcs->d_kind == DK_UNION_MEMBER) {
   1134  1.275    rillig 		o = dcs->d_offset_in_bits;
   1135  1.275    rillig 		dcs->d_offset_in_bits = 0;
   1136    1.1       cgd 	}
   1137   1.83    rillig 	if (dsym->s_bitfield) {
   1138  1.322    rillig 		dcs_align(alignment_in_bits(tp), tp->t_bit_field_width);
   1139  1.275    rillig 		dsym->u.s_member.sm_offset_in_bits = dcs->d_offset_in_bits -
   1140  1.275    rillig 		    dcs->d_offset_in_bits % size_in_bits(t);
   1141  1.322    rillig 		tp->t_bit_field_offset = dcs->d_offset_in_bits -
   1142  1.275    rillig 		    dsym->u.s_member.sm_offset_in_bits;
   1143  1.322    rillig 		dcs->d_offset_in_bits += tp->t_bit_field_width;
   1144    1.1       cgd 	} else {
   1145  1.296    rillig 		dcs_align(alignment_in_bits(tp), 0);
   1146  1.275    rillig 		dsym->u.s_member.sm_offset_in_bits = dcs->d_offset_in_bits;
   1147  1.275    rillig 		dcs->d_offset_in_bits += sz;
   1148    1.1       cgd 	}
   1149  1.303    rillig 	if (dcs->d_kind == DK_UNION_MEMBER && o > dcs->d_offset_in_bits)
   1150  1.298    rillig 		dcs->d_offset_in_bits = o;
   1151    1.1       cgd 
   1152  1.124    rillig 	check_function_definition(dsym, false);
   1153   1.26   thorpej 
   1154   1.26   thorpej 	/*
   1155   1.26   thorpej 	 * Clear the BITFIELDTYPE indicator after processing each
   1156   1.26   thorpej 	 * structure element.
   1157   1.26   thorpej 	 */
   1158  1.103    rillig 	bitfieldtype_ok = false;
   1159    1.1       cgd 
   1160   1.76    rillig 	return dsym;
   1161    1.1       cgd }
   1162    1.1       cgd 
   1163  1.322    rillig /* Aligns the next structure element as required. */
   1164    1.1       cgd static void
   1165  1.322    rillig dcs_align(unsigned int member_alignment, unsigned int bit_field_width)
   1166    1.1       cgd {
   1167    1.1       cgd 
   1168  1.322    rillig 	if (member_alignment > dcs->d_sou_align_in_bits)
   1169  1.322    rillig 		dcs->d_sou_align_in_bits = member_alignment;
   1170   1.22     lukem 
   1171  1.322    rillig 	unsigned int offset = (dcs->d_offset_in_bits + member_alignment - 1)
   1172  1.322    rillig 	    & ~(member_alignment - 1);
   1173  1.322    rillig 	if (bit_field_width == 0
   1174  1.322    rillig 	    || dcs->d_offset_in_bits + bit_field_width > offset)
   1175  1.322    rillig 		dcs->d_offset_in_bits = offset;
   1176    1.1       cgd }
   1177    1.1       cgd 
   1178    1.1       cgd sym_t *
   1179  1.322    rillig set_bit_field_width(sym_t *dsym, int bit_field_width)
   1180    1.1       cgd {
   1181   1.22     lukem 
   1182    1.1       cgd 	if (dsym == NULL) {
   1183  1.246    rillig 		dsym = block_zero_alloc(sizeof(*dsym));
   1184    1.1       cgd 		dsym->s_name = unnamed;
   1185   1.81    rillig 		dsym->s_kind = FMEMBER;
   1186  1.303    rillig 		dsym->s_scl = STRUCT_MEMBER;
   1187   1.20  sommerfe 		dsym->s_type = gettyp(UINT);
   1188  1.144    rillig 		dsym->s_block_level = -1;
   1189    1.1       cgd 	}
   1190  1.247    rillig 	dsym->s_type = block_dup_type(dsym->s_type);
   1191  1.108    rillig 	dsym->s_type->t_bitfield = true;
   1192  1.322    rillig 	dsym->s_type->t_bit_field_width = bit_field_width;
   1193  1.122    rillig 	dsym->s_bitfield = true;
   1194   1.76    rillig 	return dsym;
   1195    1.1       cgd }
   1196    1.1       cgd 
   1197    1.1       cgd /*
   1198  1.190    rillig  * A sequence of asterisks and qualifiers, from right to left.  For example,
   1199  1.190    rillig  * 'const ***volatile **const volatile' results in [cvp, p, vp, p, p].  The
   1200  1.190    rillig  * leftmost 'const' is not included in this list, it is stored in dcs->d_const
   1201  1.190    rillig  * instead.
   1202    1.1       cgd  */
   1203  1.190    rillig qual_ptr *
   1204  1.190    rillig merge_qualified_pointer(qual_ptr *p1, qual_ptr *p2)
   1205    1.1       cgd {
   1206  1.190    rillig 	qual_ptr *tail;
   1207    1.1       cgd 
   1208  1.191    rillig 	if (p2 == NULL)
   1209  1.191    rillig 		return p1;	/* for optional qualifiers */
   1210  1.191    rillig 
   1211  1.189    rillig 	if (p2->p_pointer) {
   1212  1.190    rillig 		/* append p1 to p2, keeping p2 */
   1213  1.190    rillig 		for (tail = p2; tail->p_next != NULL; tail = tail->p_next)
   1214   1.22     lukem 			continue;
   1215  1.190    rillig 		tail->p_next = p1;
   1216   1.76    rillig 		return p2;
   1217  1.190    rillig 	}
   1218  1.190    rillig 
   1219  1.190    rillig 	/* merge p2 into p1, keeping p1 */
   1220  1.190    rillig 	if (p2->p_const) {
   1221  1.190    rillig 		if (p1->p_const) {
   1222  1.190    rillig 			/* duplicate '%s' */
   1223  1.190    rillig 			warning(10, "const");
   1224  1.190    rillig 		}
   1225  1.190    rillig 		p1->p_const = true;
   1226  1.190    rillig 	}
   1227  1.190    rillig 	if (p2->p_volatile) {
   1228  1.190    rillig 		if (p1->p_volatile) {
   1229  1.190    rillig 			/* duplicate '%s' */
   1230  1.190    rillig 			warning(10, "volatile");
   1231    1.1       cgd 		}
   1232  1.190    rillig 		p1->p_volatile = true;
   1233    1.1       cgd 	}
   1234  1.190    rillig 	free(p2);
   1235  1.190    rillig 	return p1;
   1236    1.1       cgd }
   1237    1.1       cgd 
   1238  1.263    rillig static type_t *
   1239  1.263    rillig block_derive_pointer(type_t *stp, bool is_const, bool is_volatile)
   1240  1.263    rillig {
   1241  1.263    rillig 	type_t *tp;
   1242  1.263    rillig 
   1243  1.263    rillig 	tp = block_derive_type(stp, PTR);
   1244  1.263    rillig 	tp->t_const = is_const;
   1245  1.263    rillig 	tp->t_volatile = is_volatile;
   1246  1.263    rillig 	return tp;
   1247  1.263    rillig }
   1248  1.263    rillig 
   1249    1.1       cgd /*
   1250   1.73    rillig  * The following 3 functions extend the type of a declarator with
   1251    1.1       cgd  * pointer, function and array types.
   1252    1.1       cgd  *
   1253  1.296    rillig  * The current type is the type built by dcs_end_type (dcs->d_type) and
   1254    1.1       cgd  * pointer, function and array types already added for this
   1255    1.1       cgd  * declarator. The new type extension is inserted between both.
   1256    1.1       cgd  */
   1257    1.1       cgd sym_t *
   1258  1.190    rillig add_pointer(sym_t *decl, qual_ptr *p)
   1259    1.1       cgd {
   1260    1.1       cgd 
   1261  1.258    rillig 	debug_dinfo(dcs);
   1262  1.258    rillig 
   1263  1.298    rillig 	type_t **tpp = &decl->s_type;
   1264  1.122    rillig 	while (*tpp != NULL && *tpp != dcs->d_type)
   1265    1.1       cgd 		tpp = &(*tpp)->t_subt;
   1266  1.255    rillig 	if (*tpp == NULL) {
   1267  1.255    rillig 		debug_step("add_pointer: unchanged '%s'",
   1268  1.255    rillig 		    type_name(decl->s_type));
   1269   1.18  christos 		return decl;
   1270  1.255    rillig 	}
   1271    1.1       cgd 
   1272  1.190    rillig 	while (p != NULL) {
   1273  1.263    rillig 		*tpp = block_derive_pointer(dcs->d_type,
   1274  1.263    rillig 		    p->p_const, p->p_volatile);
   1275  1.261    rillig 
   1276  1.263    rillig 		tpp = &(*tpp)->t_subt;
   1277  1.261    rillig 
   1278  1.298    rillig 		qual_ptr *next = p->p_next;
   1279  1.190    rillig 		free(p);
   1280  1.190    rillig 		p = next;
   1281    1.1       cgd 	}
   1282  1.255    rillig 	debug_step("add_pointer: '%s'", type_name(decl->s_type));
   1283   1.76    rillig 	return decl;
   1284    1.1       cgd }
   1285    1.1       cgd 
   1286  1.263    rillig static type_t *
   1287  1.263    rillig block_derive_array(type_t *stp, bool dim, int len)
   1288  1.263    rillig {
   1289  1.263    rillig 
   1290  1.298    rillig 	type_t *tp = block_derive_type(stp, ARRAY);
   1291  1.263    rillig 	tp->t_dim = len;
   1292  1.263    rillig 
   1293  1.268    rillig #if 0
   1294  1.268    rillig 	/*
   1295  1.268    rillig 	 * As of 2022-04-03, the implementation of the type parser (see
   1296  1.268    rillig 	 * add_function, add_array, add_pointer) is strange.  When it sees
   1297  1.268    rillig 	 * the type 'void *b[4]', it first creates 'void b[4]' and only later
   1298  1.298    rillig 	 * inserts the '*' in the middle of the type.  Late modifications like
   1299  1.298    rillig 	 * these should not be done at all, instead the parser should be fixed
   1300  1.298    rillig 	 * to process the type names in the proper syntactical order.
   1301  1.268    rillig 	 *
   1302  1.268    rillig 	 * Since the intermediate type would be an array of void, but the
   1303  1.268    rillig 	 * final type is valid, this check cannot be enabled yet.
   1304  1.268    rillig 	 */
   1305  1.268    rillig 	if (stp->t_tspec == VOID) {
   1306  1.268    rillig 		/* array of incomplete type */
   1307  1.268    rillig 		error(301);
   1308  1.268    rillig 		tp->t_subt = gettyp(CHAR);
   1309  1.268    rillig 	}
   1310  1.268    rillig #endif
   1311  1.263    rillig 	if (len < 0) {
   1312  1.263    rillig 		/* negative array dimension (%d) */
   1313  1.263    rillig 		error(20, len);
   1314  1.263    rillig 	} else if (len == 0 && dim) {
   1315  1.263    rillig 		/* zero sized array is a C99 extension */
   1316  1.263    rillig 		c99ism(322);
   1317  1.263    rillig 	} else if (len == 0 && !dim)
   1318  1.263    rillig 		tp->t_incomplete_array = true;
   1319  1.263    rillig 
   1320  1.263    rillig 	return tp;
   1321  1.263    rillig }
   1322  1.263    rillig 
   1323    1.1       cgd /*
   1324  1.157    rillig  * If a dimension was specified, dim is true, otherwise false
   1325    1.1       cgd  * n is the specified dimension
   1326    1.1       cgd  */
   1327    1.1       cgd sym_t *
   1328  1.122    rillig add_array(sym_t *decl, bool dim, int n)
   1329    1.1       cgd {
   1330    1.1       cgd 
   1331  1.258    rillig 	debug_dinfo(dcs);
   1332  1.258    rillig 
   1333  1.298    rillig 	type_t **tpp = &decl->s_type;
   1334  1.122    rillig 	while (*tpp != NULL && *tpp != dcs->d_type)
   1335    1.1       cgd 		tpp = &(*tpp)->t_subt;
   1336  1.255    rillig 	if (*tpp == NULL) {
   1337  1.255    rillig 		debug_step("add_array: unchanged '%s'",
   1338  1.255    rillig 		    type_name(decl->s_type));
   1339  1.254    rillig 		return decl;
   1340  1.255    rillig 	}
   1341    1.1       cgd 
   1342  1.263    rillig 	*tpp = block_derive_array(dcs->d_type, dim, n);
   1343    1.1       cgd 
   1344  1.255    rillig 	debug_step("add_array: '%s'", type_name(decl->s_type));
   1345   1.76    rillig 	return decl;
   1346    1.1       cgd }
   1347    1.1       cgd 
   1348  1.263    rillig static type_t *
   1349  1.263    rillig block_derive_function(type_t *ret, bool proto, sym_t *args, bool vararg)
   1350  1.263    rillig {
   1351  1.263    rillig 
   1352  1.298    rillig 	type_t *tp = block_derive_type(ret, FUNC);
   1353  1.263    rillig 	tp->t_proto = proto;
   1354  1.263    rillig 	if (proto)
   1355  1.263    rillig 		tp->t_args = args;
   1356  1.263    rillig 	tp->t_vararg = vararg;
   1357  1.263    rillig 	return tp;
   1358  1.263    rillig }
   1359  1.263    rillig 
   1360    1.1       cgd sym_t *
   1361   1.75    rillig add_function(sym_t *decl, sym_t *args)
   1362    1.1       cgd {
   1363    1.1       cgd 
   1364  1.258    rillig 	debug_enter();
   1365  1.258    rillig 	debug_dinfo(dcs);
   1366  1.258    rillig 	debug_sym("decl: ", decl, "\n");
   1367  1.258    rillig #ifdef DEBUG
   1368  1.258    rillig 	for (const sym_t *arg = args; arg != NULL; arg = arg->s_next)
   1369  1.258    rillig 		debug_sym("arg: ", arg, "\n");
   1370  1.258    rillig #endif
   1371  1.258    rillig 
   1372    1.3       jpo 	if (dcs->d_proto) {
   1373  1.279    rillig 		if (!allow_c90)
   1374    1.1       cgd 			/* function prototypes are illegal in traditional C */
   1375    1.1       cgd 			warning(270);
   1376  1.267    rillig 		args = new_style_function(args);
   1377    1.1       cgd 	} else {
   1378   1.75    rillig 		old_style_function(decl, args);
   1379    1.1       cgd 	}
   1380    1.1       cgd 
   1381    1.1       cgd 	/*
   1382  1.160    rillig 	 * The symbols are removed from the symbol table by
   1383  1.160    rillig 	 * end_declaration_level after add_function. To be able to restore
   1384  1.259    rillig 	 * them if this is a function definition, a pointer to the list of
   1385  1.259    rillig 	 * all symbols is stored in dcs->d_enclosing->d_func_proto_syms. Also
   1386  1.259    rillig 	 * a list of the arguments (concatenated by s_next) is stored in
   1387  1.259    rillig 	 * dcs->d_enclosing->d_func_args. (dcs->d_enclosing must be used
   1388  1.259    rillig 	 * because *dcs is the declaration stack element created for the list
   1389  1.259    rillig 	 * of params and is removed after add_function.)
   1390  1.259    rillig 	 */
   1391  1.276    rillig 	if (dcs->d_enclosing->d_kind == DK_EXTERN &&
   1392  1.259    rillig 	    decl->s_type == dcs->d_enclosing->d_type) {
   1393  1.259    rillig 		dcs->d_enclosing->d_func_proto_syms = dcs->d_dlsyms;
   1394  1.259    rillig 		dcs->d_enclosing->d_func_args = args;
   1395    1.1       cgd 	}
   1396    1.1       cgd 
   1397  1.237    rillig 	/*
   1398  1.237    rillig 	 * XXX: What is this code doing on a semantic level, and why?
   1399  1.237    rillig 	 * Returning decl leads to the wrong function types in msg_347.
   1400  1.237    rillig 	 */
   1401  1.298    rillig 	type_t **tpp = &decl->s_type;
   1402  1.257    rillig 	if (*tpp == NULL)
   1403  1.259    rillig 		decl->s_type = dcs->d_enclosing->d_type;
   1404  1.259    rillig 	while (*tpp != NULL && *tpp != dcs->d_enclosing->d_type)
   1405  1.237    rillig 		/*
   1406  1.237    rillig 		 * XXX: accessing INT->t_subt feels strange, even though it
   1407  1.237    rillig 		 * may even be guaranteed to be NULL.
   1408  1.237    rillig 		 */
   1409    1.1       cgd 		tpp = &(*tpp)->t_subt;
   1410  1.255    rillig 	if (*tpp == NULL) {
   1411  1.255    rillig 		debug_step("add_function: unchanged '%s'",
   1412  1.255    rillig 		    type_name(decl->s_type));
   1413  1.258    rillig 		debug_leave();
   1414  1.254    rillig 		return decl;	/* see msg_347 */
   1415  1.255    rillig 	}
   1416    1.1       cgd 
   1417  1.263    rillig 	*tpp = block_derive_function(dcs->d_enclosing->d_type,
   1418  1.263    rillig 	    dcs->d_proto, args, dcs->d_vararg);
   1419    1.1       cgd 
   1420  1.261    rillig 	debug_step("add_function: '%s'", type_name(decl->s_type));
   1421  1.258    rillig 	debug_leave();
   1422   1.76    rillig 	return decl;
   1423    1.1       cgd }
   1424    1.1       cgd 
   1425    1.1       cgd static sym_t *
   1426  1.267    rillig new_style_function(sym_t *args)
   1427    1.1       cgd {
   1428  1.316    rillig 	sym_t *arg, *sym;
   1429  1.316    rillig 	scl_t sc;
   1430    1.1       cgd 
   1431    1.1       cgd 	/*
   1432    1.1       cgd 	 * Declarations of structs/unions/enums in param lists are legal,
   1433    1.1       cgd 	 * but senseless.
   1434    1.1       cgd 	 */
   1435  1.248    rillig 	for (sym = dcs->d_dlsyms; sym != NULL; sym = sym->s_level_next) {
   1436    1.1       cgd 		sc = sym->s_scl;
   1437  1.137    rillig 		if (sc == STRUCT_TAG || sc == UNION_TAG || sc == ENUM_TAG) {
   1438  1.291    rillig 			/* dubious tag declaration '%s %s' */
   1439   1.77    rillig 			warning(85, storage_class_name(sc), sym->s_name);
   1440    1.1       cgd 		}
   1441    1.1       cgd 	}
   1442    1.1       cgd 
   1443   1.80    rillig 	for (arg = args; arg != NULL; arg = arg->s_next) {
   1444  1.238    rillig 		if (arg->s_type->t_tspec == VOID &&
   1445  1.238    rillig 		    !(arg == args && arg->s_next == NULL)) {
   1446  1.238    rillig 			/* void must be sole parameter */
   1447  1.238    rillig 			error(60);
   1448  1.238    rillig 			arg->s_type = gettyp(INT);
   1449    1.1       cgd 		}
   1450    1.1       cgd 	}
   1451    1.1       cgd 
   1452  1.239    rillig 	if (args == NULL || args->s_type->t_tspec == VOID)
   1453  1.239    rillig 		return NULL;
   1454  1.239    rillig 	return args;
   1455    1.1       cgd }
   1456    1.1       cgd 
   1457    1.1       cgd /*
   1458  1.300    rillig  * Called for old-style function declarations.
   1459    1.1       cgd  */
   1460    1.1       cgd static void
   1461   1.75    rillig old_style_function(sym_t *decl, sym_t *args)
   1462    1.1       cgd {
   1463   1.22     lukem 
   1464    1.1       cgd 	/*
   1465  1.251    rillig 	 * Remember list of parameters only if this really seems to be a
   1466  1.251    rillig 	 * function definition.
   1467    1.1       cgd 	 */
   1468  1.276    rillig 	if (dcs->d_enclosing->d_kind == DK_EXTERN &&
   1469  1.259    rillig 	    decl->s_type == dcs->d_enclosing->d_type) {
   1470    1.1       cgd 		/*
   1471    1.1       cgd 		 * We assume that this becomes a function definition. If
   1472  1.251    rillig 		 * we are wrong, it's corrected in check_function_definition.
   1473    1.1       cgd 		 */
   1474    1.1       cgd 		if (args != NULL) {
   1475  1.122    rillig 			decl->s_osdef = true;
   1476  1.271    rillig 			decl->u.s_old_style_args = args;
   1477    1.1       cgd 		}
   1478    1.1       cgd 	} else {
   1479    1.1       cgd 		if (args != NULL)
   1480    1.1       cgd 			/* function prototype parameters must have types */
   1481    1.1       cgd 			warning(62);
   1482    1.1       cgd 	}
   1483    1.1       cgd }
   1484    1.1       cgd 
   1485    1.1       cgd /*
   1486  1.306    rillig  * In a function declaration, a list of identifiers (as opposed to a list of
   1487  1.306    rillig  * types) is allowed only if it's also a function definition.
   1488    1.1       cgd  */
   1489    1.1       cgd void
   1490  1.122    rillig check_function_definition(sym_t *sym, bool msg)
   1491    1.1       cgd {
   1492   1.22     lukem 
   1493    1.1       cgd 	if (sym->s_osdef) {
   1494    1.1       cgd 		if (msg) {
   1495    1.1       cgd 			/* incomplete or misplaced function definition */
   1496    1.1       cgd 			error(22);
   1497    1.1       cgd 		}
   1498  1.122    rillig 		sym->s_osdef = false;
   1499  1.271    rillig 		sym->u.s_old_style_args = NULL;
   1500    1.1       cgd 	}
   1501    1.1       cgd }
   1502    1.1       cgd 
   1503    1.1       cgd /*
   1504    1.1       cgd  * Process the name in a declarator.
   1505   1.73    rillig  * The symbol gets one of the storage classes EXTERN, STATIC, AUTO or
   1506    1.1       cgd  * TYPEDEF.
   1507  1.249    rillig  * s_def and s_register are valid after declarator_name().
   1508    1.1       cgd  */
   1509    1.1       cgd sym_t *
   1510   1.75    rillig declarator_name(sym_t *sym)
   1511    1.1       cgd {
   1512  1.316    rillig 	scl_t sc = NOSCL;
   1513    1.1       cgd 
   1514  1.298    rillig 	if (sym->s_scl == NOSCL)
   1515  1.154    rillig 		dcs->d_redeclared_symbol = NULL;
   1516  1.298    rillig 	else if (sym->s_defarg) {
   1517  1.122    rillig 		sym->s_defarg = false;
   1518  1.154    rillig 		dcs->d_redeclared_symbol = NULL;
   1519    1.1       cgd 	} else {
   1520  1.154    rillig 		dcs->d_redeclared_symbol = sym;
   1521    1.1       cgd 		sym = pushdown(sym);
   1522    1.1       cgd 	}
   1523    1.1       cgd 
   1524  1.276    rillig 	switch (dcs->d_kind) {
   1525  1.303    rillig 	case DK_STRUCT_MEMBER:
   1526  1.303    rillig 	case DK_UNION_MEMBER:
   1527   1.73    rillig 		/* Set parent */
   1528  1.308    rillig 		sym->u.s_member.sm_sou_type = dcs->d_tagtyp->t_sou;
   1529    1.1       cgd 		sym->s_def = DEF;
   1530  1.303    rillig 		sc = dcs->d_kind == DK_STRUCT_MEMBER
   1531  1.303    rillig 		    ? STRUCT_MEMBER
   1532  1.303    rillig 		    : UNION_MEMBER;
   1533    1.1       cgd 		break;
   1534  1.276    rillig 	case DK_EXTERN:
   1535    1.1       cgd 		/*
   1536    1.1       cgd 		 * static and external symbols without "extern" are
   1537  1.276    rillig 		 * considered to be tentatively defined, external
   1538    1.1       cgd 		 * symbols with "extern" are declared, and typedef names
   1539  1.306    rillig 		 * are defined. Tentatively defined and declared symbols
   1540    1.1       cgd 		 * may become defined if an initializer is present or
   1541    1.1       cgd 		 * this is a function definition.
   1542    1.1       cgd 		 */
   1543    1.3       jpo 		if ((sc = dcs->d_scl) == NOSCL) {
   1544    1.1       cgd 			sc = EXTERN;
   1545    1.1       cgd 			sym->s_def = TDEF;
   1546  1.298    rillig 		} else if (sc == STATIC)
   1547    1.1       cgd 			sym->s_def = TDEF;
   1548  1.298    rillig 		else if (sc == TYPEDEF)
   1549    1.1       cgd 			sym->s_def = DEF;
   1550  1.298    rillig 		else {
   1551   1.93    rillig 			lint_assert(sc == EXTERN);
   1552    1.1       cgd 			sym->s_def = DECL;
   1553    1.1       cgd 		}
   1554    1.1       cgd 		break;
   1555  1.276    rillig 	case DK_PROTO_ARG:
   1556  1.122    rillig 		sym->s_arg = true;
   1557    1.1       cgd 		/* FALLTHROUGH */
   1558  1.276    rillig 	case DK_OLD_STYLE_ARG:
   1559  1.298    rillig 		if ((sc = dcs->d_scl) == NOSCL)
   1560    1.1       cgd 			sc = AUTO;
   1561  1.298    rillig 		else {
   1562   1.93    rillig 			lint_assert(sc == REG);
   1563  1.249    rillig 			sym->s_register = true;
   1564    1.1       cgd 			sc = AUTO;
   1565    1.1       cgd 		}
   1566    1.1       cgd 		sym->s_def = DEF;
   1567    1.1       cgd 		break;
   1568  1.276    rillig 	case DK_AUTO:
   1569    1.3       jpo 		if ((sc = dcs->d_scl) == NOSCL) {
   1570    1.1       cgd 			/*
   1571  1.317    rillig 			 * XXX somewhat ugly because we don't know whether
   1572    1.1       cgd 			 * this is AUTO or EXTERN (functions). If we are
   1573  1.116    rillig 			 * wrong it must be corrected in declare_local(),
   1574  1.116    rillig 			 * where we have the necessary type information.
   1575    1.1       cgd 			 */
   1576    1.1       cgd 			sc = AUTO;
   1577    1.1       cgd 			sym->s_def = DEF;
   1578  1.298    rillig 		} else if (sc == AUTO || sc == STATIC || sc == TYPEDEF)
   1579    1.1       cgd 			sym->s_def = DEF;
   1580  1.298    rillig 		else if (sc == REG) {
   1581  1.249    rillig 			sym->s_register = true;
   1582    1.1       cgd 			sc = AUTO;
   1583    1.1       cgd 			sym->s_def = DEF;
   1584   1.93    rillig 		} else {
   1585   1.93    rillig 			lint_assert(sc == EXTERN);
   1586    1.1       cgd 			sym->s_def = DECL;
   1587    1.1       cgd 		}
   1588    1.1       cgd 		break;
   1589  1.276    rillig 	case DK_ABSTRACT:	/* try to continue after syntax errors */
   1590  1.264    rillig 		sc = NOSCL;
   1591  1.264    rillig 		break;
   1592    1.1       cgd 	default:
   1593  1.124    rillig 		lint_assert(/*CONSTCOND*/false);
   1594    1.1       cgd 	}
   1595    1.1       cgd 	sym->s_scl = sc;
   1596    1.1       cgd 
   1597    1.3       jpo 	sym->s_type = dcs->d_type;
   1598    1.1       cgd 
   1599  1.156    rillig 	dcs->d_func_proto_syms = NULL;
   1600    1.1       cgd 
   1601   1.76    rillig 	return sym;
   1602    1.1       cgd }
   1603    1.1       cgd 
   1604    1.1       cgd /*
   1605  1.300    rillig  * Process a name in the list of formal parameters in an old-style function
   1606    1.1       cgd  * definition.
   1607    1.1       cgd  */
   1608    1.1       cgd sym_t *
   1609   1.75    rillig old_style_function_name(sym_t *sym)
   1610    1.1       cgd {
   1611   1.22     lukem 
   1612    1.1       cgd 	if (sym->s_scl != NOSCL) {
   1613  1.144    rillig 		if (block_level == sym->s_block_level) {
   1614  1.285    rillig 			/* redeclaration of formal parameter '%s' */
   1615    1.1       cgd 			error(21, sym->s_name);
   1616   1.92    rillig 			lint_assert(sym->s_defarg);
   1617    1.1       cgd 		}
   1618    1.1       cgd 		sym = pushdown(sym);
   1619    1.1       cgd 	}
   1620    1.1       cgd 	sym->s_type = gettyp(INT);
   1621    1.1       cgd 	sym->s_scl = AUTO;
   1622    1.1       cgd 	sym->s_def = DEF;
   1623  1.122    rillig 	sym->s_defarg = sym->s_arg = true;
   1624   1.76    rillig 	return sym;
   1625    1.1       cgd }
   1626    1.1       cgd 
   1627    1.1       cgd /*
   1628    1.1       cgd  * Create the type of a tag.
   1629    1.1       cgd  *
   1630    1.1       cgd  * tag points to the symbol table entry of the tag
   1631    1.1       cgd  * kind is the kind of the tag (STRUCT/UNION/ENUM)
   1632  1.122    rillig  * decl is true if the type of the tag will be completed in this declaration
   1633    1.1       cgd  * (the following token is T_LBRACE)
   1634  1.122    rillig  * semi is true if the following token is T_SEMI
   1635    1.1       cgd  */
   1636    1.1       cgd type_t *
   1637  1.297    rillig make_tag_type(sym_t *tag, tspec_t kind, bool decl, bool semi)
   1638    1.1       cgd {
   1639  1.316    rillig 	scl_t scl;
   1640  1.316    rillig 	type_t *tp;
   1641    1.1       cgd 
   1642  1.298    rillig 	if (kind == STRUCT)
   1643  1.137    rillig 		scl = STRUCT_TAG;
   1644  1.298    rillig 	else if (kind == UNION)
   1645  1.137    rillig 		scl = UNION_TAG;
   1646  1.298    rillig 	else {
   1647   1.92    rillig 		lint_assert(kind == ENUM);
   1648  1.137    rillig 		scl = ENUM_TAG;
   1649    1.1       cgd 	}
   1650    1.1       cgd 
   1651    1.1       cgd 	if (tag != NULL) {
   1652  1.298    rillig 		if (tag->s_scl != NOSCL)
   1653  1.297    rillig 			tag = new_tag(tag, scl, decl, semi);
   1654  1.298    rillig 		else {
   1655    1.1       cgd 			/* a new tag, no empty declaration */
   1656  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1657  1.137    rillig 			if (scl == ENUM_TAG && !decl) {
   1658  1.280    rillig 				/* TODO: Make this an error in C99 mode as well. */
   1659  1.298    rillig 				if (allow_c90 &&
   1660  1.298    rillig 				    ((!allow_trad && !allow_c99) || pflag))
   1661    1.1       cgd 					/* forward reference to enum type */
   1662    1.1       cgd 					warning(42);
   1663    1.1       cgd 			}
   1664    1.1       cgd 		}
   1665    1.1       cgd 		if (tag->s_scl == NOSCL) {
   1666    1.1       cgd 			tag->s_scl = scl;
   1667  1.246    rillig 			tag->s_type = tp = block_zero_alloc(sizeof(*tp));
   1668  1.109    rillig 			tp->t_packed = dcs->d_packed;
   1669  1.298    rillig 		} else
   1670    1.1       cgd 			tp = tag->s_type;
   1671  1.298    rillig 
   1672    1.1       cgd 	} else {
   1673  1.246    rillig 		tag = block_zero_alloc(sizeof(*tag));
   1674    1.1       cgd 		tag->s_name = unnamed;
   1675   1.84    rillig 		UNIQUE_CURR_POS(tag->s_def_pos);
   1676    1.1       cgd 		tag->s_kind = FTAG;
   1677    1.1       cgd 		tag->s_scl = scl;
   1678  1.144    rillig 		tag->s_block_level = -1;
   1679  1.246    rillig 		tag->s_type = tp = block_zero_alloc(sizeof(*tp));
   1680  1.109    rillig 		tp->t_packed = dcs->d_packed;
   1681  1.259    rillig 		dcs->d_enclosing->d_nonempty_decl = true;
   1682    1.1       cgd 	}
   1683    1.1       cgd 
   1684  1.311    rillig 	if (tp->t_tspec == NO_TSPEC) {
   1685    1.1       cgd 		tp->t_tspec = kind;
   1686    1.1       cgd 		if (kind != ENUM) {
   1687  1.308    rillig 			tp->t_sou = block_zero_alloc(sizeof(*tp->t_sou));
   1688  1.308    rillig 			tp->t_sou->sou_align_in_bits = CHAR_SIZE;
   1689  1.308    rillig 			tp->t_sou->sou_tag = tag;
   1690  1.308    rillig 			tp->t_sou->sou_incomplete = true;
   1691    1.1       cgd 		} else {
   1692  1.136    rillig 			tp->t_is_enum = true;
   1693  1.246    rillig 			tp->t_enum = block_zero_alloc(sizeof(*tp->t_enum));
   1694  1.135    rillig 			tp->t_enum->en_tag = tag;
   1695  1.262    rillig 			tp->t_enum->en_incomplete = true;
   1696    1.1       cgd 		}
   1697    1.1       cgd 	}
   1698   1.76    rillig 	return tp;
   1699    1.1       cgd }
   1700    1.1       cgd 
   1701    1.1       cgd /*
   1702    1.1       cgd  * Checks all possible cases of tag redeclarations.
   1703  1.122    rillig  * decl is true if T_LBRACE follows
   1704  1.122    rillig  * semi is true if T_SEMI follows
   1705    1.1       cgd  */
   1706    1.1       cgd static sym_t *
   1707  1.297    rillig new_tag(sym_t *tag, scl_t scl, bool decl, bool semi)
   1708    1.1       cgd {
   1709   1.22     lukem 
   1710  1.144    rillig 	if (tag->s_block_level < block_level) {
   1711    1.1       cgd 		if (semi) {
   1712    1.1       cgd 			/* "struct a;" */
   1713  1.279    rillig 			if (allow_c90) {
   1714  1.280    rillig 				/* XXX: Why is this warning suppressed in C90 mode? */
   1715  1.280    rillig 				if (allow_trad || allow_c99)
   1716  1.290    rillig 					/* declaration of '%s %s' intro... */
   1717   1.77    rillig 					warning(44, storage_class_name(scl),
   1718   1.77    rillig 					    tag->s_name);
   1719    1.1       cgd 				tag = pushdown(tag);
   1720    1.1       cgd 			} else if (tag->s_scl != scl) {
   1721   1.88    rillig 				/* base type is really '%s %s' */
   1722   1.77    rillig 				warning(45, storage_class_name(tag->s_scl),
   1723   1.77    rillig 				    tag->s_name);
   1724    1.1       cgd 			}
   1725  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1726    1.1       cgd 		} else if (decl) {
   1727   1.22     lukem 			/* "struct a { ... } " */
   1728    1.1       cgd 			if (hflag)
   1729  1.290    rillig 				/* redefinition of '%s' hides earlier one */
   1730    1.1       cgd 				warning(43, tag->s_name);
   1731    1.1       cgd 			tag = pushdown(tag);
   1732  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1733    1.1       cgd 		} else if (tag->s_scl != scl) {
   1734   1.88    rillig 			/* base type is really '%s %s' */
   1735   1.77    rillig 			warning(45, storage_class_name(tag->s_scl),
   1736   1.77    rillig 			    tag->s_name);
   1737  1.280    rillig 			/* XXX: Why is this warning suppressed in C90 mode? */
   1738  1.280    rillig 			if (allow_trad || allow_c99) {
   1739  1.290    rillig 				/* declaration of '%s %s' introduces ... */
   1740   1.77    rillig 				warning(44, storage_class_name(scl),
   1741   1.77    rillig 				    tag->s_name);
   1742   1.77    rillig 			}
   1743    1.1       cgd 			tag = pushdown(tag);
   1744  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1745    1.1       cgd 		}
   1746    1.1       cgd 	} else {
   1747  1.231    rillig 		if (tag->s_scl != scl ||
   1748  1.231    rillig 		    (decl && !is_incomplete(tag->s_type))) {
   1749  1.222    rillig 			/* %s tag '%s' redeclared as %s */
   1750  1.222    rillig 			error(46, storage_class_name(tag->s_scl),
   1751  1.222    rillig 			    tag->s_name, storage_class_name(scl));
   1752  1.299    rillig 			print_previous_declaration(tag);
   1753    1.1       cgd 			tag = pushdown(tag);
   1754  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1755  1.298    rillig 		} else if (semi || decl)
   1756  1.259    rillig 			dcs->d_enclosing->d_nonempty_decl = true;
   1757    1.1       cgd 	}
   1758   1.76    rillig 	return tag;
   1759    1.1       cgd }
   1760    1.1       cgd 
   1761    1.1       cgd const char *
   1762   1.77    rillig storage_class_name(scl_t sc)
   1763    1.1       cgd {
   1764    1.1       cgd 	switch (sc) {
   1765  1.195    rillig 	case EXTERN:	return "extern";
   1766  1.195    rillig 	case STATIC:	return "static";
   1767  1.195    rillig 	case AUTO:	return "auto";
   1768  1.195    rillig 	case REG:	return "register";
   1769  1.195    rillig 	case TYPEDEF:	return "typedef";
   1770  1.195    rillig 	case STRUCT_TAG:return "struct";
   1771  1.195    rillig 	case UNION_TAG:	return "union";
   1772  1.195    rillig 	case ENUM_TAG:	return "enum";
   1773  1.124    rillig 	default:	lint_assert(/*CONSTCOND*/false);
   1774    1.1       cgd 	}
   1775  1.225    rillig 	/* NOTREACHED */
   1776    1.1       cgd }
   1777    1.1       cgd 
   1778    1.1       cgd type_t *
   1779  1.319    rillig complete_struct_or_union(sym_t *first_member)
   1780    1.1       cgd {
   1781    1.1       cgd 
   1782  1.319    rillig 	type_t *tp = dcs->d_tagtyp;
   1783  1.188    rillig 	if (tp == NULL)		/* in case of syntax errors */
   1784  1.188    rillig 		return gettyp(INT);
   1785  1.188    rillig 
   1786  1.296    rillig 	dcs_align((u_int)dcs->d_sou_align_in_bits, 0);
   1787  1.298    rillig 
   1788  1.308    rillig 	struct_or_union *sp = tp->t_sou;
   1789  1.194    rillig 	sp->sou_align_in_bits = dcs->d_sou_align_in_bits;
   1790  1.319    rillig 	sp->sou_incomplete = false;
   1791  1.319    rillig 	sp->sou_first_member = first_member;
   1792  1.109    rillig 	if (tp->t_packed)
   1793  1.297    rillig 		set_packed_size(tp);
   1794   1.78    rillig 	else
   1795  1.275    rillig 		sp->sou_size_in_bits = dcs->d_offset_in_bits;
   1796   1.78    rillig 
   1797  1.149    rillig 	if (sp->sou_size_in_bits == 0) {
   1798  1.250    rillig 		/* zero sized %s is a C99 feature */
   1799  1.319    rillig 		c99ism(47, tspec_name(tp->t_tspec));
   1800   1.78    rillig 	}
   1801   1.63  christos 
   1802  1.298    rillig 	int n = 0;
   1803  1.319    rillig 	for (sym_t *mem = first_member; mem != NULL; mem = mem->s_next) {
   1804   1.78    rillig 		/* bind anonymous members to the structure */
   1805  1.273    rillig 		if (mem->u.s_member.sm_sou_type == NULL) {
   1806  1.273    rillig 			mem->u.s_member.sm_sou_type = sp;
   1807  1.108    rillig 			if (mem->s_type->t_bitfield) {
   1808  1.322    rillig 				sp->sou_size_in_bits += bit_field_width(&mem);
   1809   1.78    rillig 				if (mem == NULL)
   1810   1.78    rillig 					break;
   1811   1.63  christos 			}
   1812  1.225    rillig 			sp->sou_size_in_bits +=
   1813  1.226    rillig 			    type_size_in_bits(mem->s_type);
   1814   1.63  christos 		}
   1815   1.78    rillig 		if (mem->s_name != unnamed)
   1816   1.78    rillig 			n++;
   1817   1.78    rillig 	}
   1818   1.63  christos 
   1819  1.149    rillig 	if (n == 0 && sp->sou_size_in_bits != 0) {
   1820  1.293    rillig 		/* '%s' has no named members */
   1821  1.293    rillig 		warning(65, type_name(tp));
   1822    1.1       cgd 	}
   1823   1.76    rillig 	return tp;
   1824    1.1       cgd }
   1825    1.1       cgd 
   1826   1.78    rillig type_t *
   1827  1.319    rillig complete_enum(sym_t *first_enumerator)
   1828   1.78    rillig {
   1829   1.78    rillig 
   1830  1.319    rillig 	type_t *tp = dcs->d_tagtyp;
   1831  1.262    rillig 	tp->t_enum->en_incomplete = false;
   1832  1.302    rillig 	tp->t_enum->en_first_enumerator = first_enumerator;
   1833   1.78    rillig 	return tp;
   1834   1.78    rillig }
   1835   1.78    rillig 
   1836    1.1       cgd /*
   1837   1.73    rillig  * Processes the name of an enumerator in an enum declaration.
   1838    1.1       cgd  *
   1839    1.1       cgd  * sym points to the enumerator
   1840    1.1       cgd  * val is the value of the enumerator
   1841  1.122    rillig  * impl is true if the value of the enumerator was not explicitly specified.
   1842    1.1       cgd  */
   1843    1.1       cgd sym_t *
   1844  1.122    rillig enumeration_constant(sym_t *sym, int val, bool impl)
   1845    1.1       cgd {
   1846   1.22     lukem 
   1847  1.122    rillig 	if (sym->s_scl != NOSCL) {
   1848  1.144    rillig 		if (sym->s_block_level == block_level) {
   1849  1.290    rillig 			/* no hflag, because this is illegal */
   1850    1.1       cgd 			if (sym->s_arg) {
   1851  1.290    rillig 				/* enumeration constant '%s' hides parameter */
   1852    1.1       cgd 				warning(57, sym->s_name);
   1853    1.1       cgd 			} else {
   1854  1.285    rillig 				/* redeclaration of '%s' */
   1855    1.1       cgd 				error(27, sym->s_name);
   1856    1.1       cgd 				/*
   1857  1.317    rillig 				 * Inside blocks, it should not be too
   1858   1.73    rillig 				 * complicated to find the position of the
   1859   1.73    rillig 				 * previous declaration
   1860    1.1       cgd 				 */
   1861  1.144    rillig 				if (block_level == 0)
   1862  1.299    rillig 					print_previous_declaration(sym);
   1863    1.1       cgd 			}
   1864    1.1       cgd 		} else {
   1865    1.1       cgd 			if (hflag)
   1866  1.290    rillig 				/* redefinition of '%s' hides earlier one */
   1867    1.1       cgd 				warning(43, sym->s_name);
   1868    1.1       cgd 		}
   1869    1.1       cgd 		sym = pushdown(sym);
   1870    1.1       cgd 	}
   1871  1.298    rillig 
   1872  1.272    rillig 	sym->s_scl = ENUM_CONST;
   1873    1.3       jpo 	sym->s_type = dcs->d_tagtyp;
   1874  1.273    rillig 	sym->u.s_enum_constant = val;
   1875  1.298    rillig 
   1876  1.269    rillig 	if (impl && val == TARG_INT_MIN) {
   1877  1.290    rillig 		/* enumeration value '%s' overflows */
   1878    1.1       cgd 		warning(48, sym->s_name);
   1879    1.1       cgd 	}
   1880  1.298    rillig 
   1881  1.269    rillig 	enumval = val == TARG_INT_MAX ? TARG_INT_MIN : val + 1;
   1882   1.76    rillig 	return sym;
   1883    1.1       cgd }
   1884    1.1       cgd 
   1885  1.306    rillig static bool
   1886  1.306    rillig ends_with(const char *s, const char *suffix)
   1887  1.306    rillig {
   1888  1.306    rillig 	size_t s_len = strlen(s);
   1889  1.306    rillig 	size_t suffix_len = strlen(suffix);
   1890  1.306    rillig 	return s_len >= suffix_len &&
   1891  1.306    rillig 	       memcmp(s + s_len - suffix_len, suffix, suffix_len) == 0;
   1892  1.306    rillig }
   1893  1.306    rillig 
   1894  1.306    rillig static void
   1895  1.306    rillig check_extern_declaration(const sym_t *sym)
   1896  1.306    rillig {
   1897  1.306    rillig 
   1898  1.306    rillig 	if (sym->s_scl == EXTERN &&
   1899  1.306    rillig 	    dcs->d_redeclared_symbol == NULL &&
   1900  1.309    rillig 	    ends_with(curr_pos.p_file, ".c") &&
   1901  1.309    rillig 	    !ch_isdigit(sym->s_name[0])) {	/* see mktempsym */
   1902  1.310    rillig 		/* missing%s header declaration for '%s' */
   1903  1.310    rillig 		warning(351, sym->s_type->t_tspec == FUNC ? "" : " 'extern'",
   1904  1.310    rillig 		    sym->s_name);
   1905  1.306    rillig 	}
   1906  1.318    rillig 	if (any_query_enabled &&
   1907  1.318    rillig 	    sym->s_type->t_tspec == FUNC &&
   1908  1.318    rillig 	    sym->s_scl == EXTERN &&
   1909  1.318    rillig 	    sym->s_def == DECL &&
   1910  1.318    rillig 	    !in_system_header) {
   1911  1.318    rillig 		/* redundant 'extern' in function declaration of '%s' */
   1912  1.318    rillig 		query_message(13, sym->s_name);
   1913  1.318    rillig 	}
   1914  1.306    rillig }
   1915  1.306    rillig 
   1916  1.306    rillig /* Process a single external or 'static' declarator. */
   1917  1.165    rillig static void
   1918  1.312    rillig declare_extern(sym_t *dsym, bool has_initializer, sbuf_t *renaming)
   1919    1.1       cgd {
   1920  1.166    rillig 
   1921  1.166    rillig 	if (renaming != NULL) {
   1922  1.166    rillig 		lint_assert(dsym->s_rename == NULL);
   1923  1.166    rillig 
   1924  1.298    rillig 		char *s = level_zero_alloc(1, renaming->sb_len + 1);
   1925  1.166    rillig 		(void)memcpy(s, renaming->sb_name, renaming->sb_len + 1);
   1926  1.166    rillig 		dsym->s_rename = s;
   1927  1.166    rillig 	}
   1928    1.1       cgd 
   1929  1.306    rillig 	check_extern_declaration(dsym);
   1930  1.306    rillig 
   1931  1.124    rillig 	check_function_definition(dsym, true);
   1932    1.1       cgd 
   1933   1.75    rillig 	check_type(dsym);
   1934    1.1       cgd 
   1935  1.312    rillig 	if (has_initializer && !check_init(dsym))
   1936    1.1       cgd 		dsym->s_def = DEF;
   1937    1.1       cgd 
   1938    1.1       cgd 	/*
   1939   1.75    rillig 	 * Declarations of functions are marked as "tentative" in
   1940   1.75    rillig 	 * declarator_name(). This is wrong because there are no
   1941   1.75    rillig 	 * tentative function definitions.
   1942    1.1       cgd 	 */
   1943    1.1       cgd 	if (dsym->s_type->t_tspec == FUNC && dsym->s_def == TDEF)
   1944    1.1       cgd 		dsym->s_def = DECL;
   1945    1.1       cgd 
   1946    1.4       jpo 	if (dcs->d_inline) {
   1947    1.4       jpo 		if (dsym->s_type->t_tspec == FUNC) {
   1948  1.122    rillig 			dsym->s_inline = true;
   1949    1.4       jpo 		} else {
   1950  1.284    rillig 			/* variable '%s' declared inline */
   1951    1.5       jpo 			warning(268, dsym->s_name);
   1952    1.4       jpo 		}
   1953    1.4       jpo 	}
   1954    1.4       jpo 
   1955    1.1       cgd 	/* Write the declaration into the output file */
   1956    1.1       cgd 	if (plibflg && llibflg &&
   1957    1.1       cgd 	    dsym->s_type->t_tspec == FUNC && dsym->s_type->t_proto) {
   1958    1.1       cgd 		/*
   1959  1.111    rillig 		 * With both LINTLIBRARY and PROTOLIB the prototype is
   1960    1.1       cgd 		 * written as a function definition to the output file.
   1961    1.1       cgd 		 */
   1962  1.298    rillig 		bool rval = dsym->s_type->t_subt->t_tspec != VOID;
   1963  1.124    rillig 		outfdef(dsym, &dsym->s_def_pos, rval, false, NULL);
   1964  1.313    rillig 	} else if (!is_compiler_builtin(dsym->s_name)
   1965  1.313    rillig 	    && !(has_initializer && dsym->s_type->t_incomplete_array)) {
   1966    1.4       jpo 		outsym(dsym, dsym->s_scl, dsym->s_def);
   1967    1.1       cgd 	}
   1968    1.1       cgd 
   1969  1.314    rillig 	sym_t *rdsym = dcs->d_redeclared_symbol;
   1970  1.314    rillig 	if (rdsym != NULL) {
   1971    1.1       cgd 
   1972    1.1       cgd 		/*
   1973  1.300    rillig 		 * If the old symbol stems from an old-style function
   1974  1.271    rillig 		 * definition, we have remembered the params in
   1975  1.271    rillig 		 * rdsym->s_old_style_args and compare them with the params
   1976  1.271    rillig 		 * of the prototype.
   1977    1.1       cgd 		 */
   1978  1.298    rillig 		bool redec = rdsym->s_osdef && dsym->s_type->t_proto &&
   1979  1.298    rillig 		    check_old_style_definition(rdsym, dsym);
   1980   1.22     lukem 
   1981  1.298    rillig 		bool dowarn = false;
   1982  1.298    rillig 		if (!redec && !check_redeclaration(dsym, &dowarn)) {
   1983   1.44  dholland 			if (dowarn) {
   1984  1.280    rillig 				/* TODO: Make this an error in C99 mode as well. */
   1985  1.280    rillig 				if (!allow_trad && !allow_c99)
   1986  1.285    rillig 					/* redeclaration of '%s' */
   1987  1.105    rillig 					error(27, dsym->s_name);
   1988  1.105    rillig 				else
   1989  1.285    rillig 					/* redeclaration of '%s' */
   1990  1.105    rillig 					warning(27, dsym->s_name);
   1991  1.299    rillig 				print_previous_declaration(rdsym);
   1992    1.1       cgd 			}
   1993    1.1       cgd 
   1994    1.1       cgd 			/*
   1995   1.73    rillig 			 * Take over the remembered params if the new symbol
   1996    1.4       jpo 			 * is not a prototype.
   1997    1.1       cgd 			 */
   1998    1.1       cgd 			if (rdsym->s_osdef && !dsym->s_type->t_proto) {
   1999    1.1       cgd 				dsym->s_osdef = rdsym->s_osdef;
   2000  1.271    rillig 				dsym->u.s_old_style_args =
   2001  1.271    rillig 				    rdsym->u.s_old_style_args;
   2002   1.85    rillig 				dsym->s_def_pos = rdsym->s_def_pos;
   2003    1.1       cgd 			}
   2004    1.1       cgd 
   2005  1.298    rillig 			if (rdsym->s_type->t_proto && !dsym->s_type->t_proto)
   2006   1.85    rillig 				dsym->s_def_pos = rdsym->s_def_pos;
   2007  1.298    rillig 			else if (rdsym->s_def == DEF && dsym->s_def != DEF)
   2008   1.85    rillig 				dsym->s_def_pos = rdsym->s_def_pos;
   2009    1.1       cgd 
   2010   1.75    rillig 			copy_usage_info(dsym, rdsym);
   2011    1.1       cgd 
   2012    1.1       cgd 			/* Once a name is defined, it remains defined. */
   2013    1.1       cgd 			if (rdsym->s_def == DEF)
   2014    1.1       cgd 				dsym->s_def = DEF;
   2015    1.1       cgd 
   2016    1.4       jpo 			/* once a function is inline, it remains inline */
   2017    1.4       jpo 			if (rdsym->s_inline)
   2018  1.122    rillig 				dsym->s_inline = true;
   2019    1.4       jpo 
   2020   1.75    rillig 			complete_type(dsym, rdsym);
   2021    1.1       cgd 		}
   2022   1.22     lukem 
   2023    1.1       cgd 		rmsym(rdsym);
   2024    1.1       cgd 	}
   2025    1.1       cgd 
   2026    1.1       cgd 	if (dsym->s_scl == TYPEDEF) {
   2027  1.247    rillig 		dsym->s_type = block_dup_type(dsym->s_type);
   2028  1.122    rillig 		dsym->s_type->t_typedef = true;
   2029  1.297    rillig 		set_first_typedef(dsym->s_type, dsym);
   2030    1.1       cgd 	}
   2031    1.1       cgd }
   2032    1.1       cgd 
   2033  1.165    rillig void
   2034  1.312    rillig declare(sym_t *decl, bool has_initializer, sbuf_t *renaming)
   2035  1.165    rillig {
   2036  1.165    rillig 
   2037  1.298    rillig 	if (dcs->d_kind == DK_EXTERN)
   2038  1.312    rillig 		declare_extern(decl, has_initializer, renaming);
   2039  1.298    rillig 	else if (dcs->d_kind == DK_OLD_STYLE_ARG ||
   2040  1.298    rillig 		 dcs->d_kind == DK_PROTO_ARG) {
   2041  1.165    rillig 		if (renaming != NULL) {
   2042  1.165    rillig 			/* symbol renaming can't be used on function arguments */
   2043  1.165    rillig 			error(310);
   2044  1.166    rillig 		} else
   2045  1.312    rillig 			(void)declare_argument(decl, has_initializer);
   2046  1.166    rillig 	} else {
   2047  1.276    rillig 		lint_assert(dcs->d_kind == DK_AUTO);
   2048  1.165    rillig 		if (renaming != NULL) {
   2049  1.165    rillig 			/* symbol renaming can't be used on automatic variables */
   2050  1.165    rillig 			error(311);
   2051  1.166    rillig 		} else
   2052  1.312    rillig 			declare_local(decl, has_initializer);
   2053  1.165    rillig 	}
   2054  1.165    rillig }
   2055  1.165    rillig 
   2056    1.1       cgd /*
   2057   1.73    rillig  * Copies information about usage into a new symbol table entry of
   2058    1.1       cgd  * the same symbol.
   2059    1.1       cgd  */
   2060    1.1       cgd void
   2061   1.75    rillig copy_usage_info(sym_t *sym, sym_t *rdsym)
   2062    1.1       cgd {
   2063   1.22     lukem 
   2064   1.84    rillig 	sym->s_set_pos = rdsym->s_set_pos;
   2065   1.84    rillig 	sym->s_use_pos = rdsym->s_use_pos;
   2066    1.1       cgd 	sym->s_set = rdsym->s_set;
   2067    1.1       cgd 	sym->s_used = rdsym->s_used;
   2068    1.1       cgd }
   2069    1.1       cgd 
   2070    1.1       cgd /*
   2071  1.131    rillig  * Prints an error and returns true if a symbol is redeclared/redefined.
   2072  1.298    rillig  * Otherwise, returns false and, in some cases of minor problems, prints
   2073    1.1       cgd  * a warning.
   2074    1.1       cgd  */
   2075  1.122    rillig bool
   2076  1.122    rillig check_redeclaration(sym_t *dsym, bool *dowarn)
   2077    1.1       cgd {
   2078    1.1       cgd 
   2079  1.314    rillig 	sym_t *rdsym = dcs->d_redeclared_symbol;
   2080  1.314    rillig 	if (rdsym->s_scl == ENUM_CONST) {
   2081  1.285    rillig 		/* redeclaration of '%s' */
   2082    1.1       cgd 		error(27, dsym->s_name);
   2083  1.314    rillig 		print_previous_declaration(rdsym);
   2084  1.122    rillig 		return true;
   2085    1.1       cgd 	}
   2086  1.314    rillig 	if (rdsym->s_scl == TYPEDEF) {
   2087  1.289    rillig 		/* typedef '%s' redeclared */
   2088    1.1       cgd 		error(89, dsym->s_name);
   2089  1.314    rillig 		print_previous_declaration(rdsym);
   2090  1.122    rillig 		return true;
   2091    1.1       cgd 	}
   2092    1.1       cgd 	if (dsym->s_scl == TYPEDEF) {
   2093  1.285    rillig 		/* redeclaration of '%s' */
   2094    1.1       cgd 		error(27, dsym->s_name);
   2095  1.314    rillig 		print_previous_declaration(rdsym);
   2096  1.122    rillig 		return true;
   2097    1.1       cgd 	}
   2098  1.314    rillig 	if (rdsym->s_def == DEF && dsym->s_def == DEF) {
   2099  1.288    rillig 		/* redefinition of '%s' */
   2100    1.1       cgd 		error(28, dsym->s_name);
   2101  1.314    rillig 		print_previous_declaration(rdsym);
   2102  1.122    rillig 		return true;
   2103    1.1       cgd 	}
   2104  1.314    rillig 	if (!types_compatible(rdsym->s_type, dsym->s_type, false, false, dowarn)) {
   2105  1.236    rillig 		/* redeclaration of '%s' with type '%s', expected '%s' */
   2106  1.236    rillig 		error(347, dsym->s_name,
   2107  1.314    rillig 		    type_name(dsym->s_type), type_name(rdsym->s_type));
   2108  1.314    rillig 		print_previous_declaration(rdsym);
   2109  1.122    rillig 		return true;
   2110    1.1       cgd 	}
   2111  1.314    rillig 	if (rdsym->s_scl == EXTERN && dsym->s_scl == EXTERN)
   2112  1.122    rillig 		return false;
   2113  1.314    rillig 	if (rdsym->s_scl == STATIC && dsym->s_scl == STATIC)
   2114  1.122    rillig 		return false;
   2115  1.314    rillig 	if (rdsym->s_scl == STATIC && dsym->s_def == DECL)
   2116  1.122    rillig 		return false;
   2117  1.314    rillig 	if (rdsym->s_scl == EXTERN && rdsym->s_def == DEF) {
   2118    1.1       cgd 		/*
   2119   1.66     kamil 		 * All cases except "int a = 1; static int a;" are caught
   2120    1.1       cgd 		 * above with or without a warning
   2121    1.1       cgd 		 */
   2122  1.285    rillig 		/* redeclaration of '%s' */
   2123    1.1       cgd 		error(27, dsym->s_name);
   2124  1.314    rillig 		print_previous_declaration(rdsym);
   2125  1.122    rillig 		return true;
   2126    1.1       cgd 	}
   2127  1.314    rillig 	if (rdsym->s_scl == EXTERN) {
   2128  1.288    rillig 		/* '%s' was previously declared extern, becomes static */
   2129    1.1       cgd 		warning(29, dsym->s_name);
   2130  1.314    rillig 		print_previous_declaration(rdsym);
   2131  1.122    rillig 		return false;
   2132    1.1       cgd 	}
   2133    1.1       cgd 	/*
   2134   1.86    rillig 	 * Now it's one of:
   2135    1.1       cgd 	 * "static a; int a;", "static a; int a = 1;", "static a = 1; int a;"
   2136    1.1       cgd 	 */
   2137  1.280    rillig 	/* TODO: Make this an error in C99 mode as well. */
   2138  1.280    rillig 	if (!allow_trad && !allow_c99) {
   2139  1.285    rillig 		/* redeclaration of '%s'; ANSI C requires static */
   2140    1.1       cgd 		warning(30, dsym->s_name);
   2141  1.314    rillig 		print_previous_declaration(rdsym);
   2142    1.1       cgd 	}
   2143    1.1       cgd 	dsym->s_scl = STATIC;
   2144  1.122    rillig 	return false;
   2145    1.1       cgd }
   2146    1.1       cgd 
   2147  1.117    rillig static bool
   2148  1.122    rillig qualifiers_correspond(const type_t *tp1, const type_t *tp2, bool ignqual)
   2149   1.45  christos {
   2150  1.298    rillig 
   2151  1.279    rillig 	if (tp1->t_const != tp2->t_const && !ignqual && allow_c90)
   2152  1.117    rillig 		return false;
   2153  1.279    rillig 	if (tp1->t_volatile != tp2->t_volatile && !ignqual && allow_c90)
   2154  1.117    rillig 		return false;
   2155  1.117    rillig 	return true;
   2156   1.45  christos }
   2157   1.45  christos 
   2158  1.117    rillig bool
   2159  1.298    rillig pointer_types_are_compatible(const type_t *tp1, const type_t *tp2, bool ignqual)
   2160   1.45  christos {
   2161   1.45  christos 
   2162  1.298    rillig 	return tp1->t_tspec == VOID || tp2->t_tspec == VOID ||
   2163  1.298    rillig 	       qualifiers_correspond(tp1, tp2, ignqual);
   2164   1.45  christos }
   2165   1.45  christos 
   2166    1.1       cgd /*
   2167  1.298    rillig  * ignqual	ignore qualifiers of type; used for function parameters
   2168  1.298    rillig  * promot	promote the left type; used for comparison of parameters of
   2169  1.298    rillig  *		old-style function definitions with parameters of prototypes.
   2170  1.298    rillig  * *dowarn	is set to true if an old-style function declaration is not
   2171    1.1       cgd  *		compatible with a prototype
   2172    1.1       cgd  */
   2173  1.122    rillig bool
   2174  1.298    rillig types_compatible(const type_t *tp1, const type_t *tp2,
   2175  1.298    rillig 		     bool ignqual, bool promot, bool *dowarn)
   2176    1.1       cgd {
   2177    1.1       cgd 
   2178    1.1       cgd 	while (tp1 != NULL && tp2 != NULL) {
   2179  1.298    rillig 		tspec_t t = tp1->t_tspec;
   2180    1.1       cgd 		if (promot) {
   2181  1.298    rillig 			if (t == FLOAT)
   2182    1.1       cgd 				t = DOUBLE;
   2183  1.298    rillig 			else if (t == CHAR || t == SCHAR)
   2184    1.1       cgd 				t = INT;
   2185  1.298    rillig 			else if (t == UCHAR)
   2186  1.279    rillig 				t = allow_c90 ? INT : UINT;
   2187  1.298    rillig 			else if (t == SHORT)
   2188    1.1       cgd 				t = INT;
   2189  1.298    rillig 			else if (t == USHORT) {
   2190    1.1       cgd 				/* CONSTCOND */
   2191  1.279    rillig 				t = TARG_INT_MAX < TARG_USHRT_MAX || !allow_c90
   2192  1.254    rillig 				    ? UINT : INT;
   2193    1.1       cgd 			}
   2194    1.1       cgd 		}
   2195    1.1       cgd 
   2196    1.1       cgd 		if (t != tp2->t_tspec)
   2197  1.124    rillig 			return false;
   2198    1.1       cgd 
   2199  1.116    rillig 		if (!qualifiers_correspond(tp1, tp2, ignqual))
   2200  1.124    rillig 			return false;
   2201    1.1       cgd 
   2202  1.292    rillig 		if (is_struct_or_union(t))
   2203  1.308    rillig 			return tp1->t_sou == tp2->t_sou;
   2204    1.1       cgd 
   2205  1.219    rillig 		if (t == ENUM && eflag)
   2206  1.219    rillig 			return tp1->t_enum == tp2->t_enum;
   2207  1.219    rillig 
   2208    1.1       cgd 		if (t == ARRAY && tp1->t_dim != tp2->t_dim) {
   2209    1.1       cgd 			if (tp1->t_dim != 0 && tp2->t_dim != 0)
   2210  1.124    rillig 				return false;
   2211    1.1       cgd 		}
   2212    1.1       cgd 
   2213  1.218    rillig 		/* don't check prototypes for traditional */
   2214  1.279    rillig 		if (t == FUNC && allow_c90) {
   2215    1.1       cgd 			if (tp1->t_proto && tp2->t_proto) {
   2216  1.298    rillig 				if (!prototypes_compatible(tp1, tp2, dowarn))
   2217  1.124    rillig 					return false;
   2218    1.1       cgd 			} else if (tp1->t_proto) {
   2219  1.297    rillig 				if (!matches_no_arg_function(tp1, dowarn))
   2220  1.124    rillig 					return false;
   2221    1.1       cgd 			} else if (tp2->t_proto) {
   2222  1.297    rillig 				if (!matches_no_arg_function(tp2, dowarn))
   2223  1.124    rillig 					return false;
   2224    1.1       cgd 			}
   2225    1.1       cgd 		}
   2226    1.1       cgd 
   2227    1.1       cgd 		tp1 = tp1->t_subt;
   2228    1.1       cgd 		tp2 = tp2->t_subt;
   2229  1.122    rillig 		ignqual = promot = false;
   2230    1.1       cgd 	}
   2231    1.1       cgd 
   2232   1.76    rillig 	return tp1 == tp2;
   2233    1.1       cgd }
   2234    1.1       cgd 
   2235  1.122    rillig static bool
   2236  1.298    rillig prototypes_compatible(const type_t *tp1, const type_t *tp2, bool *dowarn)
   2237    1.1       cgd {
   2238    1.1       cgd 
   2239    1.1       cgd 	if (tp1->t_vararg != tp2->t_vararg)
   2240  1.124    rillig 		return false;
   2241    1.1       cgd 
   2242  1.298    rillig 	sym_t *a1 = tp1->t_args;
   2243  1.298    rillig 	sym_t *a2 = tp2->t_args;
   2244    1.1       cgd 
   2245  1.298    rillig 	for (; a1 != NULL && a2 != NULL; a1 = a1->s_next, a2 = a2->s_next) {
   2246  1.298    rillig 		if (!types_compatible(a1->s_type, a2->s_type,
   2247  1.298    rillig 		    true, false, dowarn))
   2248  1.124    rillig 			return false;
   2249    1.1       cgd 	}
   2250   1.76    rillig 	return a1 == a2;
   2251    1.1       cgd }
   2252    1.1       cgd 
   2253    1.1       cgd /*
   2254  1.297    rillig  * Returns whether all parameters of a prototype are compatible with an
   2255  1.297    rillig  * old-style function declaration.
   2256  1.297    rillig  *
   2257   1.73    rillig  * This is the case if the following conditions are met:
   2258  1.130    rillig  *	1. the prototype has a fixed number of parameters
   2259    1.1       cgd  *	2. no parameter is of type float
   2260    1.1       cgd  *	3. no parameter is converted to another type if integer promotion
   2261    1.1       cgd  *	   is applied on it
   2262    1.1       cgd  */
   2263  1.122    rillig static bool
   2264  1.297    rillig matches_no_arg_function(const type_t *tp, bool *dowarn)
   2265    1.1       cgd {
   2266  1.316    rillig 	sym_t *arg;
   2267  1.316    rillig 	tspec_t t;
   2268    1.1       cgd 
   2269  1.298    rillig 	if (tp->t_vararg && dowarn != NULL)
   2270  1.298    rillig 		*dowarn = true;
   2271   1.80    rillig 	for (arg = tp->t_args; arg != NULL; arg = arg->s_next) {
   2272    1.1       cgd 		if ((t = arg->s_type->t_tspec) == FLOAT ||
   2273    1.1       cgd 		    t == CHAR || t == SCHAR || t == UCHAR ||
   2274    1.1       cgd 		    t == SHORT || t == USHORT) {
   2275   1.44  dholland 			if (dowarn != NULL)
   2276  1.122    rillig 				*dowarn = true;
   2277    1.1       cgd 		}
   2278    1.1       cgd 	}
   2279  1.298    rillig 	/* FIXME: Always returning true cannot be correct. */
   2280  1.122    rillig 	return true;
   2281    1.1       cgd }
   2282    1.1       cgd 
   2283    1.1       cgd /*
   2284    1.1       cgd  * Compares a prototype declaration with the remembered arguments of
   2285  1.300    rillig  * a previous old-style function definition.
   2286    1.1       cgd  */
   2287  1.122    rillig static bool
   2288   1.75    rillig check_old_style_definition(sym_t *rdsym, sym_t *dsym)
   2289    1.1       cgd {
   2290  1.316    rillig 	sym_t *args, *pargs, *arg, *parg;
   2291  1.316    rillig 	int narg, nparg, n;
   2292  1.316    rillig 	bool dowarn, msg;
   2293    1.1       cgd 
   2294  1.271    rillig 	args = rdsym->u.s_old_style_args;
   2295    1.1       cgd 	pargs = dsym->s_type->t_args;
   2296    1.1       cgd 
   2297  1.122    rillig 	msg = false;
   2298    1.1       cgd 
   2299    1.1       cgd 	narg = nparg = 0;
   2300   1.80    rillig 	for (arg = args; arg != NULL; arg = arg->s_next)
   2301    1.1       cgd 		narg++;
   2302   1.80    rillig 	for (parg = pargs; parg != NULL; parg = parg->s_next)
   2303    1.1       cgd 		nparg++;
   2304    1.1       cgd 	if (narg != nparg) {
   2305    1.1       cgd 		/* prototype does not match old-style definition */
   2306    1.1       cgd 		error(63);
   2307  1.122    rillig 		msg = true;
   2308    1.1       cgd 		goto end;
   2309    1.1       cgd 	}
   2310    1.1       cgd 
   2311    1.1       cgd 	arg = args;
   2312    1.1       cgd 	parg = pargs;
   2313    1.1       cgd 	n = 1;
   2314  1.122    rillig 	while (narg-- > 0) {
   2315  1.122    rillig 		dowarn = false;
   2316    1.1       cgd 		/*
   2317  1.280    rillig 		 * If it does not match due to promotion and lint runs in
   2318  1.280    rillig 		 * "traditional to C90" migration mode, print only a warning.
   2319  1.280    rillig 		 *
   2320  1.280    rillig 		 * XXX: Where is this "only a warning"?
   2321    1.1       cgd 		 */
   2322  1.298    rillig 		if (!types_compatible(arg->s_type, parg->s_type,
   2323  1.298    rillig 		    true, true, &dowarn) ||
   2324  1.124    rillig 		    dowarn) {
   2325  1.300    rillig 			/* prototype does not match old-style ... */
   2326    1.1       cgd 			error(299, n);
   2327  1.122    rillig 			msg = true;
   2328    1.1       cgd 		}
   2329   1.80    rillig 		arg = arg->s_next;
   2330   1.80    rillig 		parg = parg->s_next;
   2331    1.1       cgd 		n++;
   2332    1.1       cgd 	}
   2333    1.1       cgd 
   2334  1.254    rillig end:
   2335  1.299    rillig 	if (msg && rflag) {
   2336  1.300    rillig 		/* old-style definition */
   2337  1.299    rillig 		message_at(300, &rdsym->s_def_pos);
   2338  1.299    rillig 	}
   2339    1.6       jpo 
   2340   1.76    rillig 	return msg;
   2341    1.1       cgd }
   2342    1.1       cgd 
   2343    1.1       cgd /*
   2344   1.73    rillig  * Completes a type by copying the dimension and prototype information
   2345    1.1       cgd  * from a second compatible type.
   2346    1.1       cgd  *
   2347    1.1       cgd  * Following lines are legal:
   2348    1.1       cgd  *  "typedef a[]; a b; a b[10]; a c; a c[20];"
   2349    1.1       cgd  *  "typedef ft(); ft f; f(int); ft g; g(long);"
   2350    1.1       cgd  * This means that, if a type is completed, the type structure must
   2351    1.1       cgd  * be duplicated.
   2352    1.1       cgd  */
   2353    1.1       cgd void
   2354   1.75    rillig complete_type(sym_t *dsym, sym_t *ssym)
   2355    1.1       cgd {
   2356  1.298    rillig 	type_t **dstp, *src;
   2357  1.298    rillig 	type_t *dst;
   2358    1.1       cgd 
   2359    1.1       cgd 	dstp = &dsym->s_type;
   2360    1.1       cgd 	src = ssym->s_type;
   2361    1.1       cgd 
   2362    1.1       cgd 	while ((dst = *dstp) != NULL) {
   2363   1.92    rillig 		lint_assert(src != NULL);
   2364   1.92    rillig 		lint_assert(dst->t_tspec == src->t_tspec);
   2365    1.1       cgd 		if (dst->t_tspec == ARRAY) {
   2366    1.1       cgd 			if (dst->t_dim == 0 && src->t_dim != 0) {
   2367  1.247    rillig 				*dstp = dst = block_dup_type(dst);
   2368    1.1       cgd 				dst->t_dim = src->t_dim;
   2369  1.262    rillig 				dst->t_incomplete_array = false;
   2370    1.1       cgd 			}
   2371    1.1       cgd 		} else if (dst->t_tspec == FUNC) {
   2372    1.1       cgd 			if (!dst->t_proto && src->t_proto) {
   2373  1.247    rillig 				*dstp = dst = block_dup_type(dst);
   2374  1.122    rillig 				dst->t_proto = true;
   2375    1.1       cgd 				dst->t_args = src->t_args;
   2376    1.1       cgd 			}
   2377    1.1       cgd 		}
   2378    1.1       cgd 		dstp = &dst->t_subt;
   2379    1.1       cgd 		src = src->t_subt;
   2380    1.1       cgd 	}
   2381    1.1       cgd }
   2382    1.1       cgd 
   2383    1.1       cgd /*
   2384    1.1       cgd  * Completes the declaration of a single argument.
   2385    1.1       cgd  */
   2386    1.1       cgd sym_t *
   2387  1.312    rillig declare_argument(sym_t *sym, bool has_initializer)
   2388    1.1       cgd {
   2389  1.298    rillig 	tspec_t t;
   2390    1.1       cgd 
   2391  1.124    rillig 	check_function_definition(sym, true);
   2392    1.1       cgd 
   2393   1.75    rillig 	check_type(sym);
   2394    1.1       cgd 
   2395  1.154    rillig 	if (dcs->d_redeclared_symbol != NULL &&
   2396  1.154    rillig 	    dcs->d_redeclared_symbol->s_block_level == block_level) {
   2397  1.285    rillig 		/* redeclaration of formal parameter '%s' */
   2398    1.1       cgd 		error(237, sym->s_name);
   2399  1.154    rillig 		rmsym(dcs->d_redeclared_symbol);
   2400  1.122    rillig 		sym->s_arg = true;
   2401    1.1       cgd 	}
   2402    1.1       cgd 
   2403    1.1       cgd 	if (!sym->s_arg) {
   2404  1.290    rillig 		/* declared argument '%s' is missing */
   2405    1.1       cgd 		error(53, sym->s_name);
   2406  1.122    rillig 		sym->s_arg = true;
   2407    1.1       cgd 	}
   2408    1.1       cgd 
   2409  1.312    rillig 	if (has_initializer) {
   2410  1.290    rillig 		/* cannot initialize parameter '%s' */
   2411    1.1       cgd 		error(52, sym->s_name);
   2412    1.1       cgd 	}
   2413    1.1       cgd 
   2414  1.196    rillig 	if (sym->s_type == NULL)	/* for c(void()) */
   2415  1.196    rillig 		sym->s_type = gettyp(VOID);
   2416  1.196    rillig 
   2417  1.298    rillig 	if ((t = sym->s_type->t_tspec) == ARRAY)
   2418  1.247    rillig 		sym->s_type = block_derive_type(sym->s_type->t_subt, PTR);
   2419  1.298    rillig 	else if (t == FUNC) {
   2420  1.279    rillig 		if (!allow_c90)
   2421  1.290    rillig 			/* argument '%s' has function type, should be ... */
   2422    1.1       cgd 			warning(50, sym->s_name);
   2423  1.247    rillig 		sym->s_type = block_derive_type(sym->s_type, PTR);
   2424    1.1       cgd 	} else if (t == FLOAT) {
   2425  1.279    rillig 		if (!allow_c90)
   2426    1.1       cgd 			sym->s_type = gettyp(DOUBLE);
   2427    1.1       cgd 	}
   2428    1.1       cgd 
   2429    1.4       jpo 	if (dcs->d_inline)
   2430  1.284    rillig 		/* argument '%s' declared inline */
   2431    1.5       jpo 		warning(269, sym->s_name);
   2432    1.4       jpo 
   2433    1.1       cgd 	/*
   2434  1.270    rillig 	 * Arguments must have complete types. length_in_bits prints the
   2435  1.270    rillig 	 * needed error messages (null dimension is impossible because arrays
   2436  1.270    rillig 	 * are converted to pointers).
   2437    1.1       cgd 	 */
   2438    1.1       cgd 	if (sym->s_type->t_tspec != VOID)
   2439  1.270    rillig 		(void)length_in_bits(sym->s_type, sym->s_name);
   2440    1.1       cgd 
   2441   1.67  christos 	sym->s_used = dcs->d_used;
   2442   1.75    rillig 	mark_as_set(sym);
   2443    1.1       cgd 
   2444   1.76    rillig 	return sym;
   2445    1.1       cgd }
   2446    1.1       cgd 
   2447  1.298    rillig static bool
   2448  1.298    rillig is_character_pointer(const type_t *tp)
   2449  1.298    rillig {
   2450  1.298    rillig 	tspec_t st;
   2451  1.298    rillig 
   2452  1.298    rillig 	return tp->t_tspec == PTR &&
   2453  1.298    rillig 	       (st = tp->t_subt->t_tspec,
   2454  1.298    rillig 		   st == CHAR || st == SCHAR || st == UCHAR);
   2455  1.298    rillig }
   2456  1.298    rillig 
   2457    1.1       cgd void
   2458   1.87    rillig check_func_lint_directives(void)
   2459    1.1       cgd {
   2460    1.1       cgd 
   2461    1.1       cgd 	/* check for illegal combinations of lint directives */
   2462  1.110    rillig 	if (printflike_argnum != -1 && scanflike_argnum != -1) {
   2463    1.1       cgd 		/* can't be used together: ** PRINTFLIKE ** ** SCANFLIKE ** */
   2464    1.1       cgd 		warning(289);
   2465  1.110    rillig 		printflike_argnum = scanflike_argnum = -1;
   2466    1.1       cgd 	}
   2467  1.110    rillig 	if (nvararg != -1 &&
   2468  1.110    rillig 	    (printflike_argnum != -1 || scanflike_argnum != -1)) {
   2469    1.1       cgd 		/* dubious use of ** VARARGS ** with ** %s ** */
   2470  1.110    rillig 		warning(288,
   2471  1.110    rillig 		    printflike_argnum != -1 ? "PRINTFLIKE" : "SCANFLIKE");
   2472    1.1       cgd 		nvararg = -1;
   2473    1.1       cgd 	}
   2474    1.1       cgd 
   2475    1.1       cgd 	/*
   2476    1.1       cgd 	 * check if the argument of a lint directive is compatible with the
   2477    1.1       cgd 	 * number of arguments.
   2478    1.1       cgd 	 */
   2479  1.298    rillig 	int narg = 0;
   2480  1.298    rillig 	for (sym_t *arg = dcs->d_func_args; arg != NULL; arg = arg->s_next)
   2481    1.1       cgd 		narg++;
   2482    1.1       cgd 	if (nargusg > narg) {
   2483  1.293    rillig 		/* argument number mismatch with directive ** %s ** */
   2484    1.1       cgd 		warning(283, "ARGSUSED");
   2485    1.1       cgd 		nargusg = 0;
   2486    1.1       cgd 	}
   2487    1.1       cgd 	if (nvararg > narg) {
   2488  1.293    rillig 		/* argument number mismatch with directive ** %s ** */
   2489    1.1       cgd 		warning(283, "VARARGS");
   2490    1.1       cgd 		nvararg = 0;
   2491    1.1       cgd 	}
   2492  1.110    rillig 	if (printflike_argnum > narg) {
   2493  1.293    rillig 		/* argument number mismatch with directive ** %s ** */
   2494    1.1       cgd 		warning(283, "PRINTFLIKE");
   2495  1.110    rillig 		printflike_argnum = -1;
   2496  1.110    rillig 	} else if (printflike_argnum == 0) {
   2497  1.110    rillig 		printflike_argnum = -1;
   2498    1.1       cgd 	}
   2499  1.110    rillig 	if (scanflike_argnum > narg) {
   2500  1.293    rillig 		/* argument number mismatch with directive ** %s ** */
   2501    1.1       cgd 		warning(283, "SCANFLIKE");
   2502  1.110    rillig 		scanflike_argnum = -1;
   2503  1.110    rillig 	} else if (scanflike_argnum == 0) {
   2504  1.110    rillig 		scanflike_argnum = -1;
   2505  1.110    rillig 	}
   2506  1.110    rillig 	if (printflike_argnum != -1 || scanflike_argnum != -1) {
   2507  1.110    rillig 		narg = printflike_argnum != -1
   2508  1.110    rillig 		    ? printflike_argnum : scanflike_argnum;
   2509  1.298    rillig 		sym_t *arg = dcs->d_func_args;
   2510  1.298    rillig 		for (int n = 1; n < narg; n++)
   2511   1.80    rillig 			arg = arg->s_next;
   2512  1.298    rillig 		if (!is_character_pointer(arg->s_type)) {
   2513  1.230    rillig 			/* argument %d must be 'char *' for PRINTFLIKE/... */
   2514    1.1       cgd 			warning(293, narg);
   2515  1.110    rillig 			printflike_argnum = scanflike_argnum = -1;
   2516    1.1       cgd 		}
   2517    1.1       cgd 	}
   2518   1.87    rillig }
   2519   1.87    rillig 
   2520   1.87    rillig /*
   2521  1.300    rillig  * Warn about arguments in old-style function definitions that default to int.
   2522  1.300    rillig  * Check that an old-style function definition is compatible to a previous
   2523   1.87    rillig  * prototype.
   2524   1.87    rillig  */
   2525   1.87    rillig void
   2526   1.87    rillig check_func_old_style_arguments(void)
   2527   1.87    rillig {
   2528   1.87    rillig 	sym_t *args, *arg, *pargs, *parg;
   2529  1.122    rillig 	int narg, nparg;
   2530  1.122    rillig 	bool msg;
   2531   1.87    rillig 
   2532  1.271    rillig 	args = funcsym->u.s_old_style_args;
   2533   1.87    rillig 	pargs = funcsym->s_type->t_args;
   2534    1.1       cgd 
   2535    1.1       cgd 	/*
   2536  1.300    rillig 	 * print a warning for each argument of an old-style function
   2537    1.1       cgd 	 * definition which defaults to int
   2538    1.1       cgd 	 */
   2539   1.80    rillig 	for (arg = args; arg != NULL; arg = arg->s_next) {
   2540    1.1       cgd 		if (arg->s_defarg) {
   2541  1.290    rillig 			/* type of argument '%s' defaults to 'int' */
   2542    1.1       cgd 			warning(32, arg->s_name);
   2543  1.122    rillig 			arg->s_defarg = false;
   2544   1.75    rillig 			mark_as_set(arg);
   2545    1.1       cgd 		}
   2546    1.1       cgd 	}
   2547    1.1       cgd 
   2548    1.1       cgd 	/*
   2549  1.300    rillig 	 * If this is an old-style function definition and a prototype
   2550    1.1       cgd 	 * exists, compare the types of arguments.
   2551    1.1       cgd 	 */
   2552    1.1       cgd 	if (funcsym->s_osdef && funcsym->s_type->t_proto) {
   2553    1.1       cgd 		/*
   2554   1.73    rillig 		 * If the number of arguments does not match, we need not
   2555    1.1       cgd 		 * continue.
   2556    1.1       cgd 		 */
   2557    1.1       cgd 		narg = nparg = 0;
   2558  1.122    rillig 		msg = false;
   2559   1.80    rillig 		for (parg = pargs; parg != NULL; parg = parg->s_next)
   2560    1.1       cgd 			nparg++;
   2561   1.80    rillig 		for (arg = args; arg != NULL; arg = arg->s_next)
   2562    1.1       cgd 			narg++;
   2563    1.1       cgd 		if (narg != nparg) {
   2564    1.1       cgd 			/* parameter mismatch: %d declared, %d defined */
   2565    1.1       cgd 			error(51, nparg, narg);
   2566  1.122    rillig 			msg = true;
   2567    1.1       cgd 		} else {
   2568    1.1       cgd 			parg = pargs;
   2569    1.1       cgd 			arg = args;
   2570  1.122    rillig 			while (narg-- > 0) {
   2571   1.75    rillig 				msg |= check_prototype_declaration(arg, parg);
   2572   1.80    rillig 				parg = parg->s_next;
   2573   1.80    rillig 				arg = arg->s_next;
   2574    1.1       cgd 			}
   2575    1.1       cgd 		}
   2576  1.299    rillig 		if (msg && rflag) {
   2577    1.1       cgd 			/* prototype declaration */
   2578  1.299    rillig 			message_at(285, &dcs->d_redeclared_symbol->s_def_pos);
   2579  1.298    rillig 		}
   2580    1.6       jpo 
   2581   1.73    rillig 		/* from now on the prototype is valid */
   2582  1.122    rillig 		funcsym->s_osdef = false;
   2583  1.271    rillig 		funcsym->u.s_old_style_args = NULL;
   2584    1.1       cgd 	}
   2585    1.1       cgd }
   2586    1.1       cgd 
   2587    1.1       cgd /*
   2588  1.300    rillig  * Checks compatibility of an old-style function definition with a previous
   2589    1.1       cgd  * prototype declaration.
   2590  1.122    rillig  * Returns true if the position of the previous declaration should be reported.
   2591    1.1       cgd  */
   2592  1.122    rillig static bool
   2593   1.75    rillig check_prototype_declaration(sym_t *arg, sym_t *parg)
   2594    1.1       cgd {
   2595  1.316    rillig 	type_t *tp, *ptp;
   2596  1.316    rillig 	bool dowarn;
   2597    1.1       cgd 
   2598    1.1       cgd 	tp = arg->s_type;
   2599    1.1       cgd 	ptp = parg->s_type;
   2600    1.1       cgd 
   2601  1.122    rillig 	dowarn = false;
   2602    1.6       jpo 
   2603  1.298    rillig 	if (!types_compatible(tp, ptp, true, true, &dowarn)) {
   2604  1.298    rillig 		if (types_compatible(tp, ptp, true, false, &dowarn)) {
   2605  1.290    rillig 			/* type of '%s' does not match prototype */
   2606  1.278    rillig 			return gnuism(58, arg->s_name);
   2607    1.6       jpo 		} else {
   2608  1.290    rillig 			/* type of '%s' does not match prototype */
   2609    1.6       jpo 			error(58, arg->s_name);
   2610  1.278    rillig 			return true;
   2611    1.6       jpo 		}
   2612  1.298    rillig 	}
   2613  1.298    rillig 	if (dowarn) {
   2614  1.280    rillig 		/* TODO: Make this an error in C99 mode as well. */
   2615  1.280    rillig 		if (!allow_trad && !allow_c99)
   2616  1.290    rillig 			/* type of '%s' does not match prototype */
   2617  1.105    rillig 			error(58, arg->s_name);
   2618  1.105    rillig 		else
   2619  1.290    rillig 			/* type of '%s' does not match prototype */
   2620  1.105    rillig 			warning(58, arg->s_name);
   2621  1.278    rillig 		return true;
   2622    1.1       cgd 	}
   2623    1.6       jpo 
   2624  1.278    rillig 	return false;
   2625    1.1       cgd }
   2626    1.1       cgd 
   2627  1.229    rillig static void
   2628  1.229    rillig check_local_hiding(const sym_t *dsym)
   2629  1.229    rillig {
   2630  1.229    rillig 	switch (dsym->s_scl) {
   2631  1.229    rillig 	case AUTO:
   2632  1.290    rillig 		/* automatic '%s' hides external declaration */
   2633  1.229    rillig 		warning(86, dsym->s_name);
   2634  1.229    rillig 		break;
   2635  1.229    rillig 	case STATIC:
   2636  1.290    rillig 		/* static '%s' hides external declaration */
   2637  1.229    rillig 		warning(87, dsym->s_name);
   2638  1.229    rillig 		break;
   2639  1.229    rillig 	case TYPEDEF:
   2640  1.290    rillig 		/* typedef '%s' hides external declaration */
   2641  1.229    rillig 		warning(88, dsym->s_name);
   2642  1.229    rillig 		break;
   2643  1.229    rillig 	case EXTERN:
   2644  1.229    rillig 		/* Already checked in declare_external_in_block. */
   2645  1.229    rillig 		break;
   2646  1.229    rillig 	default:
   2647  1.229    rillig 		lint_assert(/*CONSTCOND*/false);
   2648  1.229    rillig 	}
   2649  1.229    rillig }
   2650  1.229    rillig 
   2651  1.229    rillig static void
   2652  1.314    rillig check_local_redeclaration(const sym_t *dsym, sym_t *rdsym)
   2653  1.229    rillig {
   2654  1.314    rillig 	if (rdsym->s_block_level == 0) {
   2655  1.229    rillig 		if (hflag)
   2656  1.229    rillig 			check_local_hiding(dsym);
   2657  1.229    rillig 
   2658  1.314    rillig 	} else if (rdsym->s_block_level == block_level) {
   2659  1.229    rillig 
   2660  1.229    rillig 		/* no hflag, because it's illegal! */
   2661  1.314    rillig 		if (rdsym->s_arg) {
   2662  1.229    rillig 			/*
   2663  1.285    rillig 			 * if allow_c90, a "redeclaration of '%s'" error
   2664  1.229    rillig 			 * is produced below
   2665  1.229    rillig 			 */
   2666  1.279    rillig 			if (!allow_c90) {
   2667  1.298    rillig 				if (hflag) {
   2668  1.290    rillig 					/* declaration of '%s' hides ... */
   2669  1.229    rillig 					warning(91, dsym->s_name);
   2670  1.298    rillig 				}
   2671  1.314    rillig 				rmsym(rdsym);
   2672  1.229    rillig 			}
   2673  1.229    rillig 		}
   2674  1.229    rillig 
   2675  1.314    rillig 	} else if (rdsym->s_block_level < block_level) {
   2676  1.298    rillig 		if (hflag) {
   2677  1.291    rillig 			/* declaration of '%s' hides earlier one */
   2678  1.229    rillig 			warning(95, dsym->s_name);
   2679  1.298    rillig 		}
   2680  1.229    rillig 	}
   2681  1.229    rillig 
   2682  1.314    rillig 	if (rdsym->s_block_level == block_level) {
   2683  1.285    rillig 		/* redeclaration of '%s' */
   2684  1.229    rillig 		error(27, dsym->s_name);
   2685  1.314    rillig 		rmsym(rdsym);
   2686  1.229    rillig 	}
   2687  1.229    rillig }
   2688  1.229    rillig 
   2689    1.1       cgd /*
   2690    1.1       cgd  * Completes a single local declaration/definition.
   2691    1.1       cgd  */
   2692    1.1       cgd void
   2693  1.312    rillig declare_local(sym_t *dsym, bool has_initializer)
   2694    1.1       cgd {
   2695   1.22     lukem 
   2696   1.75    rillig 	/* Correct a mistake done in declarator_name(). */
   2697    1.1       cgd 	if (dsym->s_type->t_tspec == FUNC) {
   2698    1.1       cgd 		dsym->s_def = DECL;
   2699    1.3       jpo 		if (dcs->d_scl == NOSCL)
   2700    1.1       cgd 			dsym->s_scl = EXTERN;
   2701    1.1       cgd 	}
   2702    1.1       cgd 
   2703  1.307    rillig 	if (dsym->s_scl == EXTERN) {
   2704  1.307    rillig 		/* nested 'extern' declaration of '%s' */
   2705  1.307    rillig 		warning(352, dsym->s_name);
   2706  1.307    rillig 	}
   2707  1.307    rillig 
   2708    1.1       cgd 	if (dsym->s_type->t_tspec == FUNC) {
   2709    1.1       cgd 		if (dsym->s_scl == STATIC) {
   2710  1.291    rillig 			/* dubious static function '%s' at block level */
   2711    1.1       cgd 			warning(93, dsym->s_name);
   2712    1.1       cgd 			dsym->s_scl = EXTERN;
   2713    1.1       cgd 		} else if (dsym->s_scl != EXTERN && dsym->s_scl != TYPEDEF) {
   2714  1.291    rillig 			/* function '%s' has illegal storage class */
   2715    1.1       cgd 			error(94, dsym->s_name);
   2716    1.1       cgd 			dsym->s_scl = EXTERN;
   2717    1.1       cgd 		}
   2718    1.1       cgd 	}
   2719    1.1       cgd 
   2720    1.4       jpo 	/*
   2721    1.4       jpo 	 * functions may be declared inline at local scope, although
   2722    1.4       jpo 	 * this has no effect for a later definition of the same
   2723    1.4       jpo 	 * function.
   2724  1.279    rillig 	 * XXX it should have an effect if !allow_c90 is set. this would
   2725    1.4       jpo 	 * also be the way gcc behaves.
   2726    1.4       jpo 	 */
   2727    1.4       jpo 	if (dcs->d_inline) {
   2728  1.298    rillig 		if (dsym->s_type->t_tspec == FUNC)
   2729  1.122    rillig 			dsym->s_inline = true;
   2730  1.298    rillig 		else {
   2731  1.284    rillig 			/* variable '%s' declared inline */
   2732    1.5       jpo 			warning(268, dsym->s_name);
   2733    1.4       jpo 		}
   2734    1.4       jpo 	}
   2735    1.4       jpo 
   2736  1.124    rillig 	check_function_definition(dsym, true);
   2737    1.1       cgd 
   2738   1.75    rillig 	check_type(dsym);
   2739    1.1       cgd 
   2740  1.154    rillig 	if (dcs->d_redeclared_symbol != NULL && dsym->s_scl == EXTERN)
   2741  1.116    rillig 		declare_external_in_block(dsym);
   2742    1.1       cgd 
   2743    1.1       cgd 	if (dsym->s_scl == EXTERN) {
   2744    1.1       cgd 		/*
   2745   1.73    rillig 		 * XXX if the static variable at level 0 is only defined
   2746   1.73    rillig 		 * later, checking will be possible.
   2747    1.1       cgd 		 */
   2748  1.298    rillig 		if (dsym->s_ext_sym == NULL)
   2749    1.4       jpo 			outsym(dsym, EXTERN, dsym->s_def);
   2750  1.298    rillig 		else
   2751   1.83    rillig 			outsym(dsym, dsym->s_ext_sym->s_scl, dsym->s_def);
   2752    1.1       cgd 	}
   2753    1.1       cgd 
   2754  1.229    rillig 	if (dcs->d_redeclared_symbol != NULL)
   2755  1.229    rillig 		check_local_redeclaration(dsym, dcs->d_redeclared_symbol);
   2756    1.1       cgd 
   2757  1.312    rillig 	if (has_initializer && !check_init(dsym)) {
   2758    1.1       cgd 		dsym->s_def = DEF;
   2759   1.75    rillig 		mark_as_set(dsym);
   2760    1.1       cgd 	}
   2761    1.1       cgd 
   2762    1.1       cgd 	if (dsym->s_scl == TYPEDEF) {
   2763  1.247    rillig 		dsym->s_type = block_dup_type(dsym->s_type);
   2764  1.122    rillig 		dsym->s_type->t_typedef = true;
   2765  1.297    rillig 		set_first_typedef(dsym->s_type, dsym);
   2766    1.1       cgd 	}
   2767    1.1       cgd 
   2768  1.315    rillig 	if (dsym->s_scl == STATIC && any_query_enabled) {
   2769  1.315    rillig 		/* static variable '%s' in function */
   2770  1.315    rillig 		query_message(11, dsym->s_name);
   2771  1.315    rillig 	}
   2772    1.1       cgd }
   2773    1.1       cgd 
   2774  1.298    rillig /* Processes (re)declarations of external symbols inside blocks. */
   2775    1.1       cgd static void
   2776  1.116    rillig declare_external_in_block(sym_t *dsym)
   2777    1.1       cgd {
   2778    1.1       cgd 
   2779    1.1       cgd 	/* look for a symbol with the same name */
   2780  1.298    rillig 	sym_t *esym = dcs->d_redeclared_symbol;
   2781  1.144    rillig 	while (esym != NULL && esym->s_block_level != 0) {
   2782  1.248    rillig 		while ((esym = esym->s_symtab_next) != NULL) {
   2783    1.1       cgd 			if (esym->s_kind != FVFT)
   2784    1.1       cgd 				continue;
   2785    1.1       cgd 			if (strcmp(dsym->s_name, esym->s_name) == 0)
   2786    1.1       cgd 				break;
   2787    1.1       cgd 		}
   2788    1.1       cgd 	}
   2789    1.1       cgd 	if (esym == NULL)
   2790    1.1       cgd 		return;
   2791    1.1       cgd 	if (esym->s_scl != EXTERN && esym->s_scl != STATIC) {
   2792    1.1       cgd 		/* gcc accepts this without a warning, pcc prints an error. */
   2793  1.285    rillig 		/* redeclaration of '%s' */
   2794    1.1       cgd 		warning(27, dsym->s_name);
   2795  1.299    rillig 		print_previous_declaration(esym);
   2796    1.1       cgd 		return;
   2797    1.1       cgd 	}
   2798    1.1       cgd 
   2799  1.298    rillig 	bool dowarn = false;
   2800  1.298    rillig 	bool compatible = types_compatible(esym->s_type, dsym->s_type,
   2801  1.298    rillig 	    false, false, &dowarn);
   2802    1.1       cgd 
   2803  1.298    rillig 	if (!compatible || dowarn) {
   2804    1.1       cgd 		if (esym->s_scl == EXTERN) {
   2805  1.291    rillig 			/* inconsistent redeclaration of extern '%s' */
   2806    1.1       cgd 			warning(90, dsym->s_name);
   2807  1.299    rillig 			print_previous_declaration(esym);
   2808    1.1       cgd 		} else {
   2809  1.291    rillig 			/* inconsistent redeclaration of static '%s' */
   2810    1.1       cgd 			warning(92, dsym->s_name);
   2811  1.299    rillig 			print_previous_declaration(esym);
   2812    1.1       cgd 		}
   2813    1.1       cgd 	}
   2814    1.1       cgd 
   2815  1.298    rillig 	if (compatible) {
   2816    1.1       cgd 		/*
   2817  1.317    rillig 		 * Remember the external symbol, so we can update usage
   2818    1.1       cgd 		 * information at the end of the block.
   2819    1.1       cgd 		 */
   2820   1.83    rillig 		dsym->s_ext_sym = esym;
   2821    1.1       cgd 	}
   2822    1.1       cgd }
   2823    1.1       cgd 
   2824    1.1       cgd /*
   2825   1.73    rillig  * Print an error or a warning if the symbol cannot be initialized due
   2826  1.131    rillig  * to type/storage class. Return whether an error has been detected.
   2827    1.1       cgd  */
   2828  1.122    rillig static bool
   2829   1.75    rillig check_init(sym_t *sym)
   2830    1.1       cgd {
   2831  1.316    rillig 	bool erred;
   2832    1.1       cgd 
   2833  1.122    rillig 	erred = false;
   2834    1.1       cgd 
   2835    1.1       cgd 	if (sym->s_type->t_tspec == FUNC) {
   2836  1.288    rillig 		/* cannot initialize function '%s' */
   2837    1.1       cgd 		error(24, sym->s_name);
   2838  1.122    rillig 		erred = true;
   2839    1.1       cgd 	} else if (sym->s_scl == TYPEDEF) {
   2840  1.288    rillig 		/* cannot initialize typedef '%s' */
   2841    1.1       cgd 		error(25, sym->s_name);
   2842  1.122    rillig 		erred = true;
   2843    1.1       cgd 	} else if (sym->s_scl == EXTERN && sym->s_def == DECL) {
   2844  1.276    rillig 		if (dcs->d_kind == DK_EXTERN) {
   2845  1.288    rillig 			/* cannot initialize extern declaration '%s' */
   2846    1.1       cgd 			warning(26, sym->s_name);
   2847    1.1       cgd 		} else {
   2848  1.288    rillig 			/* cannot initialize extern declaration '%s' */
   2849    1.1       cgd 			error(26, sym->s_name);
   2850  1.122    rillig 			erred = true;
   2851    1.1       cgd 		}
   2852    1.1       cgd 	}
   2853    1.1       cgd 
   2854   1.76    rillig 	return erred;
   2855    1.1       cgd }
   2856    1.1       cgd 
   2857    1.1       cgd /*
   2858   1.73    rillig  * Create a symbol for an abstract declaration.
   2859    1.1       cgd  */
   2860    1.1       cgd sym_t *
   2861   1.75    rillig abstract_name(void)
   2862    1.1       cgd {
   2863  1.316    rillig 	sym_t *sym;
   2864    1.1       cgd 
   2865  1.276    rillig 	lint_assert(dcs->d_kind == DK_ABSTRACT ||
   2866  1.276    rillig 	    dcs->d_kind == DK_PROTO_ARG);
   2867    1.1       cgd 
   2868  1.246    rillig 	sym = block_zero_alloc(sizeof(*sym));
   2869    1.1       cgd 
   2870    1.1       cgd 	sym->s_name = unnamed;
   2871    1.1       cgd 	sym->s_def = DEF;
   2872    1.1       cgd 	sym->s_scl = ABSTRACT;
   2873  1.144    rillig 	sym->s_block_level = -1;
   2874    1.1       cgd 
   2875  1.276    rillig 	if (dcs->d_kind == DK_PROTO_ARG)
   2876  1.122    rillig 		sym->s_arg = true;
   2877    1.1       cgd 
   2878  1.240    rillig 	/*
   2879  1.240    rillig 	 * At this point, dcs->d_type contains only the basic type.  That
   2880  1.240    rillig 	 * type will be updated later, adding pointers, arrays and functions
   2881  1.240    rillig 	 * as necessary.
   2882  1.240    rillig 	 */
   2883  1.240    rillig 	/*
   2884  1.240    rillig 	 * XXX: This is not the correct type.  For example in msg_347, it is
   2885  1.240    rillig 	 * the type of the last prototype parameter, but it should rather be
   2886  1.240    rillig 	 * the return type of the function.
   2887  1.240    rillig 	 */
   2888    1.3       jpo 	sym->s_type = dcs->d_type;
   2889  1.154    rillig 	dcs->d_redeclared_symbol = NULL;
   2890  1.122    rillig 	dcs->d_vararg = false;
   2891    1.1       cgd 
   2892   1.76    rillig 	return sym;
   2893    1.1       cgd }
   2894    1.1       cgd 
   2895    1.1       cgd /*
   2896    1.1       cgd  * Removes anything which has nothing to do on global level.
   2897    1.1       cgd  */
   2898    1.1       cgd void
   2899   1.77    rillig global_clean_up(void)
   2900    1.1       cgd {
   2901   1.22     lukem 
   2902  1.259    rillig 	while (dcs->d_enclosing != NULL)
   2903  1.160    rillig 		end_declaration_level();
   2904    1.1       cgd 
   2905  1.253    rillig 	clean_up_after_error();
   2906  1.144    rillig 	block_level = 0;
   2907  1.144    rillig 	mem_block_level = 0;
   2908    1.1       cgd 
   2909    1.1       cgd 	/*
   2910   1.73    rillig 	 * remove all information about pending lint directives without
   2911    1.1       cgd 	 * warnings.
   2912    1.1       cgd 	 */
   2913  1.124    rillig 	global_clean_up_decl(true);
   2914    1.1       cgd }
   2915    1.1       cgd 
   2916    1.1       cgd sym_t *
   2917  1.320    rillig declare_abstract_type(sym_t *sym)
   2918    1.1       cgd {
   2919   1.22     lukem 
   2920  1.124    rillig 	check_function_definition(sym, true);
   2921   1.75    rillig 	check_type(sym);
   2922   1.76    rillig 	return sym;
   2923    1.1       cgd }
   2924    1.1       cgd 
   2925    1.1       cgd /*
   2926  1.138    rillig  * Checks size after declarations of variables and their initialization.
   2927    1.1       cgd  */
   2928    1.1       cgd void
   2929   1.75    rillig check_size(sym_t *dsym)
   2930    1.1       cgd {
   2931   1.22     lukem 
   2932  1.298    rillig 	if (dsym->s_def == DEF &&
   2933  1.298    rillig 	    dsym->s_scl != TYPEDEF &&
   2934  1.298    rillig 	    dsym->s_type->t_tspec != FUNC &&
   2935  1.298    rillig 	    length_in_bits(dsym->s_type, dsym->s_name) == 0 &&
   2936  1.298    rillig 	    dsym->s_type->t_tspec == ARRAY &&
   2937  1.298    rillig 	    dsym->s_type->t_dim == 0) {
   2938  1.279    rillig 		if (!allow_c90) {
   2939  1.293    rillig 			/* empty array declaration for '%s' */
   2940    1.1       cgd 			warning(190, dsym->s_name);
   2941    1.1       cgd 		} else {
   2942  1.293    rillig 			/* empty array declaration for '%s' */
   2943    1.1       cgd 			error(190, dsym->s_name);
   2944    1.1       cgd 		}
   2945    1.1       cgd 	}
   2946    1.1       cgd }
   2947    1.1       cgd 
   2948    1.1       cgd /*
   2949    1.1       cgd  * Mark an object as set if it is not already
   2950    1.1       cgd  */
   2951    1.1       cgd void
   2952   1.75    rillig mark_as_set(sym_t *sym)
   2953    1.1       cgd {
   2954   1.22     lukem 
   2955    1.1       cgd 	if (!sym->s_set) {
   2956  1.122    rillig 		sym->s_set = true;
   2957   1.84    rillig 		UNIQUE_CURR_POS(sym->s_set_pos);
   2958    1.1       cgd 	}
   2959    1.1       cgd }
   2960    1.1       cgd 
   2961    1.1       cgd /*
   2962    1.1       cgd  * Mark an object as used if it is not already
   2963    1.1       cgd  */
   2964    1.1       cgd void
   2965  1.122    rillig mark_as_used(sym_t *sym, bool fcall, bool szof)
   2966    1.1       cgd {
   2967   1.22     lukem 
   2968    1.1       cgd 	if (!sym->s_used) {
   2969  1.122    rillig 		sym->s_used = true;
   2970   1.84    rillig 		UNIQUE_CURR_POS(sym->s_use_pos);
   2971    1.1       cgd 	}
   2972    1.1       cgd 	/*
   2973  1.302    rillig 	 * For function calls, another record is written.
   2974    1.1       cgd 	 *
   2975  1.302    rillig 	 * XXX: Should symbols used in sizeof() be treated as used or not?
   2976  1.302    rillig 	 * Probably not, because there is no point in declaring an external
   2977  1.302    rillig 	 * variable only to get its size.
   2978    1.1       cgd 	 */
   2979    1.1       cgd 	if (!fcall && !szof && sym->s_kind == FVFT && sym->s_scl == EXTERN)
   2980    1.1       cgd 		outusg(sym);
   2981    1.1       cgd }
   2982    1.1       cgd 
   2983    1.1       cgd /*
   2984    1.1       cgd  * Prints warnings for a list of variables and labels (concatenated
   2985  1.248    rillig  * with s_level_next) if these are not used or only set.
   2986    1.1       cgd  */
   2987    1.1       cgd void
   2988   1.75    rillig check_usage(dinfo_t *di)
   2989    1.1       cgd {
   2990   1.57  christos 	/* for this warning LINTED has no effect */
   2991  1.298    rillig 	int saved_lwarn = lwarn;
   2992   1.56  christos 	lwarn = LWARN_ALL;
   2993    1.1       cgd 
   2994  1.216    rillig 	debug_step("begin lwarn %d", lwarn);
   2995  1.298    rillig 	for (sym_t *sym = di->d_dlsyms; sym != NULL; sym = sym->s_level_next)
   2996   1.75    rillig 		check_usage_sym(di->d_asm, sym);
   2997  1.282    rillig 	lwarn = saved_lwarn;
   2998  1.216    rillig 	debug_step("end lwarn %d", lwarn);
   2999    1.1       cgd }
   3000    1.1       cgd 
   3001    1.1       cgd /*
   3002    1.1       cgd  * Prints a warning for a single variable or label if it is not used or
   3003    1.1       cgd  * only set.
   3004    1.1       cgd  */
   3005    1.1       cgd void
   3006  1.122    rillig check_usage_sym(bool novar, sym_t *sym)
   3007    1.1       cgd {
   3008    1.1       cgd 
   3009  1.144    rillig 	if (sym->s_block_level == -1)
   3010    1.1       cgd 		return;
   3011    1.1       cgd 
   3012  1.177    rillig 	if (sym->s_kind == FVFT && sym->s_arg)
   3013  1.177    rillig 		check_argument_usage(novar, sym);
   3014  1.177    rillig 	else if (sym->s_kind == FVFT)
   3015  1.177    rillig 		check_variable_usage(novar, sym);
   3016  1.177    rillig 	else if (sym->s_kind == FLABEL)
   3017   1.75    rillig 		check_label_usage(sym);
   3018  1.177    rillig 	else if (sym->s_kind == FTAG)
   3019   1.75    rillig 		check_tag_usage(sym);
   3020    1.1       cgd }
   3021    1.1       cgd 
   3022    1.1       cgd static void
   3023  1.122    rillig check_argument_usage(bool novar, sym_t *arg)
   3024    1.1       cgd {
   3025   1.22     lukem 
   3026   1.92    rillig 	lint_assert(arg->s_set);
   3027    1.1       cgd 
   3028   1.10       jpo 	if (novar)
   3029   1.10       jpo 		return;
   3030   1.10       jpo 
   3031    1.1       cgd 	if (!arg->s_used && vflag) {
   3032  1.171    rillig 		/* argument '%s' unused in function '%s' */
   3033  1.178    rillig 		warning_at(231, &arg->s_def_pos, arg->s_name, funcsym->s_name);
   3034    1.1       cgd 	}
   3035    1.1       cgd }
   3036    1.1       cgd 
   3037    1.1       cgd static void
   3038  1.122    rillig check_variable_usage(bool novar, sym_t *sym)
   3039    1.1       cgd {
   3040  1.316    rillig 	scl_t sc;
   3041  1.316    rillig 	sym_t *xsym;
   3042    1.1       cgd 
   3043  1.144    rillig 	lint_assert(block_level != 0);
   3044  1.186    rillig 
   3045  1.186    rillig 	/* example at file scope: int c = ({ return 3; }); */
   3046  1.186    rillig 	if (sym->s_block_level == 0 && ch_isdigit(sym->s_name[0]))
   3047  1.186    rillig 		return;
   3048    1.1       cgd 
   3049    1.1       cgd 	/* errors in expressions easily cause lots of these warnings */
   3050    1.1       cgd 	if (nerr != 0)
   3051    1.1       cgd 		return;
   3052    1.1       cgd 
   3053    1.1       cgd 	/*
   3054   1.73    rillig 	 * XXX Only variables are checked, although types should
   3055    1.1       cgd 	 * probably also be checked
   3056    1.1       cgd 	 */
   3057  1.298    rillig 	sc = sym->s_scl;
   3058  1.298    rillig 	if (sc != EXTERN && sc != STATIC && sc != AUTO && sc != REG)
   3059    1.1       cgd 		return;
   3060   1.10       jpo 
   3061   1.10       jpo 	if (novar)
   3062   1.10       jpo 		return;
   3063    1.1       cgd 
   3064    1.1       cgd 	if (sc == EXTERN) {
   3065    1.1       cgd 		if (!sym->s_used && !sym->s_set) {
   3066  1.171    rillig 			/* '%s' unused in function '%s' */
   3067  1.178    rillig 			warning_at(192, &sym->s_def_pos,
   3068  1.177    rillig 			    sym->s_name, funcsym->s_name);
   3069    1.1       cgd 		}
   3070    1.1       cgd 	} else {
   3071    1.1       cgd 		if (sym->s_set && !sym->s_used) {
   3072  1.171    rillig 			/* '%s' set but not used in function '%s' */
   3073  1.178    rillig 			warning_at(191, &sym->s_set_pos,
   3074  1.177    rillig 			    sym->s_name, funcsym->s_name);
   3075    1.1       cgd 		} else if (!sym->s_used) {
   3076  1.171    rillig 			/* '%s' unused in function '%s' */
   3077  1.178    rillig 			warning_at(192, &sym->s_def_pos,
   3078  1.177    rillig 			    sym->s_name, funcsym->s_name);
   3079    1.1       cgd 		}
   3080    1.1       cgd 	}
   3081    1.1       cgd 
   3082    1.1       cgd 	if (sc == EXTERN) {
   3083    1.1       cgd 		/*
   3084    1.1       cgd 		 * information about usage is taken over into the symbol
   3085   1.73    rillig 		 * table entry at level 0 if the symbol was locally declared
   3086    1.1       cgd 		 * as an external symbol.
   3087    1.1       cgd 		 *
   3088    1.1       cgd 		 * XXX This is wrong for symbols declared static at level 0
   3089    1.1       cgd 		 * if the usage information stems from sizeof(). This is
   3090    1.1       cgd 		 * because symbols at level 0 only used in sizeof() are
   3091    1.1       cgd 		 * considered to not be used.
   3092    1.1       cgd 		 */
   3093   1.83    rillig 		if ((xsym = sym->s_ext_sym) != NULL) {
   3094    1.1       cgd 			if (sym->s_used && !xsym->s_used) {
   3095  1.122    rillig 				xsym->s_used = true;
   3096   1.85    rillig 				xsym->s_use_pos = sym->s_use_pos;
   3097    1.1       cgd 			}
   3098    1.1       cgd 			if (sym->s_set && !xsym->s_set) {
   3099  1.122    rillig 				xsym->s_set = true;
   3100   1.85    rillig 				xsym->s_set_pos = sym->s_set_pos;
   3101    1.1       cgd 			}
   3102    1.1       cgd 		}
   3103    1.1       cgd 	}
   3104    1.1       cgd }
   3105    1.1       cgd 
   3106    1.1       cgd static void
   3107   1.75    rillig check_label_usage(sym_t *lab)
   3108    1.1       cgd {
   3109   1.22     lukem 
   3110  1.144    rillig 	lint_assert(block_level == 1);
   3111  1.144    rillig 	lint_assert(lab->s_block_level == 1);
   3112    1.1       cgd 
   3113  1.283    rillig 	if (funcsym == NULL) {
   3114  1.283    rillig 		/* syntax error '%s' */
   3115  1.283    rillig 		error(249, "labels are only valid inside a function");
   3116  1.283    rillig 	} else if (lab->s_set && !lab->s_used) {
   3117  1.198    rillig 		/* label '%s' unused in function '%s' */
   3118  1.178    rillig 		warning_at(232, &lab->s_set_pos, lab->s_name, funcsym->s_name);
   3119    1.1       cgd 	} else if (!lab->s_set) {
   3120  1.198    rillig 		/* undefined label '%s' */
   3121  1.178    rillig 		warning_at(23, &lab->s_use_pos, lab->s_name);
   3122    1.1       cgd 	}
   3123    1.1       cgd }
   3124    1.1       cgd 
   3125    1.1       cgd static void
   3126   1.75    rillig check_tag_usage(sym_t *sym)
   3127    1.1       cgd {
   3128   1.22     lukem 
   3129  1.132    rillig 	if (!is_incomplete(sym->s_type))
   3130    1.1       cgd 		return;
   3131    1.1       cgd 
   3132   1.73    rillig 	/* always complain about incomplete tags declared inside blocks */
   3133  1.276    rillig 	if (!zflag || dcs->d_kind != DK_EXTERN)
   3134    1.1       cgd 		return;
   3135    1.1       cgd 
   3136    1.1       cgd 	switch (sym->s_type->t_tspec) {
   3137    1.1       cgd 	case STRUCT:
   3138  1.284    rillig 		/* struct '%s' never defined */
   3139  1.178    rillig 		warning_at(233, &sym->s_def_pos, sym->s_name);
   3140    1.1       cgd 		break;
   3141    1.1       cgd 	case UNION:
   3142  1.284    rillig 		/* union '%s' never defined */
   3143  1.178    rillig 		warning_at(234, &sym->s_def_pos, sym->s_name);
   3144    1.1       cgd 		break;
   3145    1.1       cgd 	case ENUM:
   3146  1.284    rillig 		/* enum '%s' never defined */
   3147  1.178    rillig 		warning_at(235, &sym->s_def_pos, sym->s_name);
   3148    1.1       cgd 		break;
   3149    1.1       cgd 	default:
   3150  1.124    rillig 		lint_assert(/*CONSTCOND*/false);
   3151    1.1       cgd 	}
   3152    1.1       cgd }
   3153    1.1       cgd 
   3154    1.1       cgd /*
   3155    1.1       cgd  * Called after the entire translation unit has been parsed.
   3156   1.73    rillig  * Changes tentative definitions into definitions.
   3157   1.73    rillig  * Performs some tests on global symbols. Detected problems are:
   3158    1.1       cgd  * - defined variables of incomplete type
   3159    1.1       cgd  * - constant variables which are not initialized
   3160    1.1       cgd  * - static symbols which are never used
   3161    1.1       cgd  */
   3162    1.1       cgd void
   3163   1.75    rillig check_global_symbols(void)
   3164    1.1       cgd {
   3165  1.316    rillig 	sym_t *sym;
   3166    1.1       cgd 
   3167  1.259    rillig 	if (block_level != 0 || dcs->d_enclosing != NULL)
   3168    1.1       cgd 		norecover();
   3169    1.1       cgd 
   3170  1.248    rillig 	for (sym = dcs->d_dlsyms; sym != NULL; sym = sym->s_level_next) {
   3171  1.144    rillig 		if (sym->s_block_level == -1)
   3172    1.1       cgd 			continue;
   3173  1.298    rillig 		if (sym->s_kind == FVFT)
   3174   1.75    rillig 			check_global_variable(sym);
   3175  1.298    rillig 		else if (sym->s_kind == FTAG)
   3176   1.75    rillig 			check_tag_usage(sym);
   3177  1.298    rillig 		else
   3178   1.92    rillig 			lint_assert(sym->s_kind == FMEMBER);
   3179    1.1       cgd 	}
   3180    1.1       cgd }
   3181    1.1       cgd 
   3182    1.1       cgd static void
   3183  1.120    rillig check_unused_static_global_variable(const sym_t *sym)
   3184  1.120    rillig {
   3185  1.120    rillig 	if (sym->s_type->t_tspec == FUNC) {
   3186  1.120    rillig 		if (sym->s_def == DEF) {
   3187  1.120    rillig 			if (!sym->s_inline)
   3188  1.284    rillig 				/* static function '%s' unused */
   3189  1.178    rillig 				warning_at(236, &sym->s_def_pos, sym->s_name);
   3190  1.120    rillig 		} else {
   3191  1.293    rillig 			/* static function '%s' declared but not defined */
   3192  1.178    rillig 			warning_at(290, &sym->s_def_pos, sym->s_name);
   3193  1.120    rillig 		}
   3194  1.120    rillig 	} else if (!sym->s_set) {
   3195  1.284    rillig 		/* static variable '%s' unused */
   3196  1.178    rillig 		warning_at(226, &sym->s_def_pos, sym->s_name);
   3197  1.120    rillig 	} else {
   3198  1.284    rillig 		/* static variable '%s' set but not used */
   3199  1.178    rillig 		warning_at(307, &sym->s_def_pos, sym->s_name);
   3200  1.120    rillig 	}
   3201  1.120    rillig }
   3202  1.120    rillig 
   3203  1.120    rillig static void
   3204  1.120    rillig check_static_global_variable(const sym_t *sym)
   3205  1.120    rillig {
   3206  1.120    rillig 	if (sym->s_type->t_tspec == FUNC && sym->s_used && sym->s_def != DEF) {
   3207  1.293    rillig 		/* static function '%s' called but not defined */
   3208  1.178    rillig 		error_at(225, &sym->s_use_pos, sym->s_name);
   3209  1.120    rillig 	}
   3210  1.120    rillig 
   3211  1.120    rillig 	if (!sym->s_used)
   3212  1.120    rillig 		check_unused_static_global_variable(sym);
   3213  1.120    rillig 
   3214  1.279    rillig 	if (allow_c90 && sym->s_def == TDEF && sym->s_type->t_const) {
   3215  1.293    rillig 		/* const object '%s' should have initializer */
   3216  1.178    rillig 		warning_at(227, &sym->s_def_pos, sym->s_name);
   3217  1.120    rillig 	}
   3218  1.120    rillig }
   3219  1.120    rillig 
   3220  1.120    rillig static void
   3221  1.120    rillig check_global_variable(const sym_t *sym)
   3222    1.1       cgd {
   3223  1.272    rillig 	scl_t scl = sym->s_scl;
   3224   1.22     lukem 
   3225  1.272    rillig 	if (scl == TYPEDEF || scl == BOOL_CONST || scl == ENUM_CONST)
   3226    1.1       cgd 		return;
   3227   1.22     lukem 
   3228  1.272    rillig 	if (scl == NOSCL)
   3229  1.119    rillig 		return;		/* May be caused by a syntax error. */
   3230  1.119    rillig 
   3231  1.272    rillig 	lint_assert(scl == EXTERN || scl == STATIC);
   3232    1.1       cgd 
   3233   1.75    rillig 	check_global_variable_size(sym);
   3234    1.1       cgd 
   3235  1.272    rillig 	if (scl == STATIC)
   3236  1.120    rillig 		check_static_global_variable(sym);
   3237    1.1       cgd }
   3238    1.1       cgd 
   3239    1.1       cgd static void
   3240  1.120    rillig check_global_variable_size(const sym_t *sym)
   3241    1.1       cgd {
   3242  1.175    rillig 	pos_t cpos;
   3243  1.270    rillig 	int len_in_bits;
   3244   1.22     lukem 
   3245  1.129    rillig 	if (sym->s_def != TDEF)
   3246  1.129    rillig 		return;
   3247  1.298    rillig 	if (sym->s_type->t_tspec == FUNC) {
   3248  1.298    rillig 		/* Maybe a syntax error after a function declaration. */
   3249  1.298    rillig 		return;
   3250  1.298    rillig 	}
   3251  1.298    rillig 	if (sym->s_def == TDEF && sym->s_type->t_tspec == VOID) {
   3252  1.298    rillig 		/* Prevent an internal error in length_in_bits below. */
   3253  1.129    rillig 		return;
   3254  1.298    rillig 	}
   3255  1.129    rillig 
   3256  1.175    rillig 	cpos = curr_pos;
   3257  1.129    rillig 	curr_pos = sym->s_def_pos;
   3258  1.270    rillig 	len_in_bits = length_in_bits(sym->s_type, sym->s_name);
   3259  1.175    rillig 	curr_pos = cpos;
   3260  1.175    rillig 
   3261  1.270    rillig 	if (len_in_bits == 0 &&
   3262  1.129    rillig 	    sym->s_type->t_tspec == ARRAY && sym->s_type->t_dim == 0) {
   3263  1.280    rillig 		/* TODO: C99 6.7.5.2p1 defines this as an error as well. */
   3264  1.280    rillig 		if (!allow_c90 ||
   3265  1.280    rillig 		    (sym->s_scl == EXTERN && (allow_trad || allow_c99))) {
   3266  1.293    rillig 			/* empty array declaration for '%s' */
   3267  1.178    rillig 			warning_at(190, &sym->s_def_pos, sym->s_name);
   3268  1.129    rillig 		} else {
   3269  1.293    rillig 			/* empty array declaration for '%s' */
   3270  1.178    rillig 			error_at(190, &sym->s_def_pos, sym->s_name);
   3271    1.1       cgd 		}
   3272    1.1       cgd 	}
   3273    1.1       cgd }
   3274    1.1       cgd 
   3275    1.1       cgd /*
   3276    1.1       cgd  * Prints information about location of previous definition/declaration.
   3277    1.1       cgd  */
   3278    1.1       cgd void
   3279  1.299    rillig print_previous_declaration(const sym_t *psym)
   3280    1.1       cgd {
   3281    1.1       cgd 
   3282    1.1       cgd 	if (!rflag)
   3283    1.1       cgd 		return;
   3284    1.1       cgd 
   3285  1.299    rillig 	if (psym->s_def == DEF || psym->s_def == TDEF) {
   3286  1.284    rillig 		/* previous definition of '%s' */
   3287  1.178    rillig 		message_at(261, &psym->s_def_pos, psym->s_name);
   3288    1.1       cgd 	} else {
   3289  1.284    rillig 		/* previous declaration of '%s' */
   3290  1.178    rillig 		message_at(260, &psym->s_def_pos, psym->s_name);
   3291    1.1       cgd 	}
   3292    1.1       cgd }
   3293  1.146    rillig 
   3294  1.146    rillig /*
   3295  1.146    rillig  * Gets a node for a constant and returns the value of this constant
   3296  1.146    rillig  * as integer.
   3297  1.146    rillig  *
   3298  1.146    rillig  * If the node is not constant or too large for int or of type float,
   3299  1.146    rillig  * a warning will be printed.
   3300  1.146    rillig  *
   3301  1.146    rillig  * to_int_constant() should be used only inside declarations. If it is used in
   3302  1.146    rillig  * expressions, it frees the memory used for the expression.
   3303  1.146    rillig  */
   3304  1.146    rillig int
   3305  1.146    rillig to_int_constant(tnode_t *tn, bool required)
   3306  1.146    rillig {
   3307  1.316    rillig 	int i;
   3308  1.316    rillig 	tspec_t t;
   3309  1.146    rillig 
   3310  1.295    rillig 	if (tn == NULL)
   3311  1.295    rillig 		return 1;
   3312  1.295    rillig 
   3313  1.298    rillig 	val_t *v = constant(tn, required);
   3314  1.146    rillig 
   3315  1.146    rillig 	/*
   3316  1.146    rillig 	 * Abstract declarations are used inside expression. To free
   3317  1.146    rillig 	 * the memory would be a fatal error.
   3318  1.146    rillig 	 * We don't free blocks that are inside casts because these
   3319  1.146    rillig 	 * will be used later to match types.
   3320  1.146    rillig 	 */
   3321  1.276    rillig 	if (tn->tn_op != CON && dcs->d_kind != DK_ABSTRACT)
   3322  1.168    rillig 		expr_free_all();
   3323  1.146    rillig 
   3324  1.146    rillig 	if ((t = v->v_tspec) == FLOAT || t == DOUBLE || t == LDOUBLE) {
   3325  1.146    rillig 		i = (int)v->v_ldbl;
   3326  1.146    rillig 		/* integral constant expression expected */
   3327  1.146    rillig 		error(55);
   3328  1.146    rillig 	} else {
   3329  1.146    rillig 		i = (int)v->v_quad;
   3330  1.146    rillig 		if (is_uinteger(t)) {
   3331  1.146    rillig 			if ((uint64_t)v->v_quad > (uint64_t)TARG_INT_MAX) {
   3332  1.146    rillig 				/* integral constant too large */
   3333  1.146    rillig 				warning(56);
   3334  1.146    rillig 			}
   3335  1.146    rillig 		} else {
   3336  1.146    rillig 			if (v->v_quad > (int64_t)TARG_INT_MAX ||
   3337  1.146    rillig 			    v->v_quad < (int64_t)TARG_INT_MIN) {
   3338  1.146    rillig 				/* integral constant too large */
   3339  1.146    rillig 				warning(56);
   3340  1.146    rillig 			}
   3341  1.146    rillig 		}
   3342  1.146    rillig 	}
   3343  1.146    rillig 
   3344  1.146    rillig 	free(v);
   3345  1.146    rillig 	return i;
   3346  1.146    rillig }
   3347