X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/95e36146a5be4c921c14f82ab80e3612866c4518..0e16927b48c881317a38132923b6f3150802a7d3:/src/symtab.c diff --git a/src/symtab.c b/src/symtab.c index 08361539..002f6e37 100644 --- a/src/symtab.c +++ b/src/symtab.c @@ -1,127 +1,971 @@ -/* Symbol table manager for Bison, - Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc. +/* Symbol table manager for Bison. + + Copyright (C) 1984, 1989, 2000-2002, 2004-2012 Free Software + Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. - Bison is free software; you can redistribute it and/or modify + This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2, or (at your option) - any later version. + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. - Bison is distributed in the hope that it will be useful, + This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with Bison; see the file COPYING. If not, write to - the Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. */ - + along with this program. If not, see . */ +#include #include "system.h" -#include "xalloc.h" -#include "symtab.h" + +#include + +#include "complain.h" #include "gram.h" +#include "symtab.h" +/*-------------------------------------------------------------------. +| Symbols sorted by tag. Allocated by the first invocation of | +| symbols_do, after which no more symbols should be created. | +`-------------------------------------------------------------------*/ -bucket *firstsymbol; -static bucket *lastsymbol; -static bucket **symtab; +static symbol **symbols_sorted = NULL; -static int -hash (const char *key) +/*------------------------. +| Distinguished symbols. | +`------------------------*/ + +symbol *errtoken = NULL; +symbol *undeftoken = NULL; +symbol *endtoken = NULL; +symbol *accept = NULL; +symbol *startsymbol = NULL; +location startsymbol_location; + +/*---------------------------------------. +| Default %destructor's and %printer's. | +`---------------------------------------*/ + +static code_props default_tagged_destructor = CODE_PROPS_NONE_INIT; +static code_props default_tagless_destructor = CODE_PROPS_NONE_INIT; +static code_props default_tagged_printer = CODE_PROPS_NONE_INIT; +static code_props default_tagless_printer = CODE_PROPS_NONE_INIT; + +/*---------------------------------. +| Create a new symbol, named TAG. | +`---------------------------------*/ + +static symbol * +symbol_new (uniqstr tag, location loc) +{ + symbol *res = xmalloc (sizeof *res); + + uniqstr_assert (tag); + + /* If the tag is not a string (starts with a double quote), check + that it is valid for Yacc. */ + if (tag[0] != '\"' && tag[0] != '\'' && mbschr (tag, '-')) + yacc_at (loc, _("POSIX Yacc forbids dashes in symbol names: %s"), + tag); + + res->tag = tag; + res->location = loc; + + res->type_name = NULL; + code_props_none_init (&res->destructor); + code_props_none_init (&res->printer); + + res->number = NUMBER_UNDEFINED; + res->prec = 0; + res->assoc = undef_assoc; + res->user_token_number = USER_NUMBER_UNDEFINED; + + res->alias = NULL; + res->class = unknown_sym; + res->declared = false; + + if (nsyms == SYMBOL_NUMBER_MAXIMUM) + fatal (_("too many symbols in input grammar (limit is %d)"), + SYMBOL_NUMBER_MAXIMUM); + nsyms++; + return res; +} + +/*----------------------------------------. +| Create a new semantic type, named TAG. | +`----------------------------------------*/ + +static semantic_type * +semantic_type_new (uniqstr tag) +{ + semantic_type *res = xmalloc (sizeof *res); + + uniqstr_assert (tag); + res->tag = tag; + code_props_none_init (&res->destructor); + code_props_none_init (&res->printer); + + return res; +} + + +/*-----------------. +| Print a symbol. | +`-----------------*/ + +#define SYMBOL_ATTR_PRINT(Attr) \ + if (s->Attr) \ + fprintf (f, " %s { %s }", #Attr, s->Attr) + +#define SYMBOL_CODE_PRINT(Attr) \ + if (s->Attr.code) \ + fprintf (f, " %s { %s }", #Attr, s->Attr.code) + +void +symbol_print (symbol *s, FILE *f) +{ + if (s) + { + fprintf (f, "\"%s\"", s->tag); + SYMBOL_ATTR_PRINT (type_name); + SYMBOL_CODE_PRINT (destructor); + SYMBOL_CODE_PRINT (printer); + } + else + fprintf (f, ""); +} + +#undef SYMBOL_ATTR_PRINT +#undef SYMBOL_CODE_PRINT + +/*------------------------------------------------------------------. +| Complain that S's WHAT is redeclared at SECOND, and was first set | +| at FIRST. | +`------------------------------------------------------------------*/ + +static void +symbol_redeclaration (symbol *s, const char *what, location first, + location second) { - const char *cp; - int k; + complain_at (second, _("%s redeclaration for %s"), what, s->tag); + complain_at (first, _("previous declaration")); +} + +static void +semantic_type_redeclaration (semantic_type *s, const char *what, location first, + location second) +{ + complain_at (second, _("%s redeclaration for <%s>"), what, s->tag); + complain_at (first, _("previous declaration")); +} - cp = key; - k = 0; - while (*cp) - k = ((k << 1) ^ (*cp++)) & 0x3fff; - return k % TABSIZE; + +/*-----------------------------------------------------------------. +| Set the TYPE_NAME associated with SYM. Does nothing if passed 0 | +| as TYPE_NAME. | +`-----------------------------------------------------------------*/ + +void +symbol_type_set (symbol *sym, uniqstr type_name, location loc) +{ + if (type_name) + { + if (sym->type_name) + symbol_redeclaration (sym, "%type", sym->type_location, loc); + uniqstr_assert (type_name); + sym->type_name = type_name; + sym->type_location = loc; + } } +/*-----------------------------------------. +| Set the DESTRUCTOR associated with SYM. | +`-----------------------------------------*/ void -tabinit (void) +symbol_destructor_set (symbol *sym, code_props const *destructor) { - symtab = XCALLOC (bucket *, TABSIZE); + if (sym->destructor.code) + symbol_redeclaration (sym, "%destructor", sym->destructor.location, + destructor->location); + sym->destructor = *destructor; +} + +/*------------------------------------------. +| Set the DESTRUCTOR associated with TYPE. | +`------------------------------------------*/ - firstsymbol = NULL; - lastsymbol = NULL; +void +semantic_type_destructor_set (semantic_type *type, + code_props const *destructor) +{ + if (type->destructor.code) + semantic_type_redeclaration (type, "%destructor", + type->destructor.location, + destructor->location); + type->destructor = *destructor; } +/*---------------------------------------. +| Get the computed %destructor for SYM. | +`---------------------------------------*/ -bucket * -getsym (const char *key) +code_props const * +symbol_destructor_get (symbol const *sym) { - int hashval; - bucket *bp; - int found; + /* Per-symbol %destructor. */ + if (sym->destructor.code) + return &sym->destructor; - hashval = hash (key); - bp = symtab[hashval]; + /* Per-type %destructor. */ + if (sym->type_name) + { + code_props const *destructor = + &semantic_type_get (sym->type_name)->destructor; + if (destructor->code) + return destructor; + } + + /* Apply default %destructor's only to user-defined symbols. */ + if (sym->tag[0] == '$' || sym == errtoken) + return &code_props_none; + + if (sym->type_name) + return &default_tagged_destructor; + return &default_tagless_destructor; +} - found = 0; - while (bp != NULL && found == 0) +/*--------------------------------------. +| Set the PRINTER associated with SYM. | +`--------------------------------------*/ + +void +symbol_printer_set (symbol *sym, code_props const *printer) +{ + if (sym->printer.code) + symbol_redeclaration (sym, "%printer", + sym->printer.location, printer->location); + sym->printer = *printer; +} + +/*---------------------------------------. +| Set the PRINTER associated with TYPE. | +`---------------------------------------*/ + +void +semantic_type_printer_set (semantic_type *type, code_props const *printer) +{ + if (type->printer.code) + semantic_type_redeclaration (type, "%printer", + type->printer.location, printer->location); + type->printer = *printer; +} + +/*------------------------------------. +| Get the computed %printer for SYM. | +`------------------------------------*/ + +code_props const * +symbol_printer_get (symbol const *sym) +{ + /* Per-symbol %printer. */ + if (sym->printer.code) + return &sym->printer; + + /* Per-type %printer. */ + if (sym->type_name) { - if (strcmp (key, bp->tag) == 0) - found = 1; + code_props const *printer = &semantic_type_get (sym->type_name)->printer; + if (printer->code) + return printer; + } + + /* Apply the default %printer only to user-defined symbols. */ + if (sym->tag[0] == '$' || sym == errtoken) + return &code_props_none; + + if (sym->type_name) + return &default_tagged_printer; + return &default_tagless_printer; +} + +/*-----------------------------------------------------------------. +| Set the PRECEDENCE associated with SYM. Does nothing if invoked | +| with UNDEF_ASSOC as ASSOC. | +`-----------------------------------------------------------------*/ + +void +symbol_precedence_set (symbol *sym, int prec, assoc a, location loc) +{ + if (a != undef_assoc) + { + if (sym->prec != 0) + symbol_redeclaration (sym, assoc_to_string (a), sym->prec_location, + loc); + sym->prec = prec; + sym->assoc = a; + sym->prec_location = loc; + } + + /* Only terminals have a precedence. */ + symbol_class_set (sym, token_sym, loc, false); +} + + +/*------------------------------------. +| Set the CLASS associated with SYM. | +`------------------------------------*/ + +void +symbol_class_set (symbol *sym, symbol_class class, location loc, bool declaring) +{ + if (sym->class != unknown_sym && sym->class != class) + { + complain_at (loc, _("symbol %s redefined"), sym->tag); + sym->declared = false; + } + + if (class == nterm_sym && sym->class != nterm_sym) + sym->number = nvars++; + else if (class == token_sym && sym->number == NUMBER_UNDEFINED) + sym->number = ntokens++; + + sym->class = class; + + if (declaring) + { + if (sym->declared) + warn_at (loc, _("symbol %s redeclared"), sym->tag); + sym->declared = true; + } +} + + +/*------------------------------------------------. +| Set the USER_TOKEN_NUMBER associated with SYM. | +`------------------------------------------------*/ + +void +symbol_user_token_number_set (symbol *sym, int user_token_number, location loc) +{ + int *user_token_numberp; + + if (sym->user_token_number != USER_NUMBER_HAS_STRING_ALIAS) + user_token_numberp = &sym->user_token_number; + else + user_token_numberp = &sym->alias->user_token_number; + if (*user_token_numberp != USER_NUMBER_UNDEFINED + && *user_token_numberp != user_token_number) + complain_at (loc, _("redefining user token number of %s"), sym->tag); + + *user_token_numberp = user_token_number; + /* User defined $end token? */ + if (user_token_number == 0) + { + endtoken = sym; + /* It is always mapped to 0, so it was already counted in + NTOKENS. */ + if (endtoken->number != NUMBER_UNDEFINED) + --ntokens; + endtoken->number = 0; + } +} + + +/*----------------------------------------------------------. +| If SYM is not defined, report an error, and consider it a | +| nonterminal. | +`----------------------------------------------------------*/ + +static inline bool +symbol_check_defined (symbol *sym) +{ + if (sym->class == unknown_sym) + { + complain_at + (sym->location, + _("symbol %s is used, but is not defined as a token and has no rules"), + sym->tag); + sym->class = nterm_sym; + sym->number = nvars++; + } + + return true; +} + +static bool +symbol_check_defined_processor (void *sym, void *null ATTRIBUTE_UNUSED) +{ + return symbol_check_defined (sym); +} + + +void +symbol_make_alias (symbol *sym, symbol *str, location loc) +{ + if (str->alias) + warn_at (loc, _("symbol %s used more than once as a literal string"), + str->tag); + else if (sym->alias) + warn_at (loc, _("symbol %s given more than one literal string"), + sym->tag); + else + { + str->class = token_sym; + str->user_token_number = sym->user_token_number; + sym->user_token_number = USER_NUMBER_HAS_STRING_ALIAS; + str->alias = sym; + sym->alias = str; + str->number = sym->number; + symbol_type_set (str, sym->type_name, loc); + } +} + + +/*---------------------------------------------------------. +| Check that THIS, and its alias, have same precedence and | +| associativity. | +`---------------------------------------------------------*/ + +static inline void +symbol_check_alias_consistency (symbol *this) +{ + symbol *sym = this; + symbol *str = this->alias; + + /* Check only the symbol in the symbol-string pair. */ + if (!(this->alias + && this->user_token_number == USER_NUMBER_HAS_STRING_ALIAS)) + return; + + if (str->type_name != sym->type_name) + { + if (str->type_name) + symbol_type_set (sym, str->type_name, str->type_location); else - bp = bp->link; + symbol_type_set (str, sym->type_name, sym->type_location); } - if (found == 0) + + if (str->destructor.code || sym->destructor.code) { - nsyms++; + if (str->destructor.code) + symbol_destructor_set (sym, &str->destructor); + else + symbol_destructor_set (str, &sym->destructor); + } - bp = XCALLOC (bucket, 1); - bp->link = symtab[hashval]; - bp->next = NULL; - bp->tag = xstrdup (key); - bp->class = unknown_sym; + if (str->printer.code || sym->printer.code) + { + if (str->printer.code) + symbol_printer_set (sym, &str->printer); + else + symbol_printer_set (str, &sym->printer); + } - if (firstsymbol == NULL) - { - firstsymbol = bp; - lastsymbol = bp; - } + if (sym->prec || str->prec) + { + if (str->prec) + symbol_precedence_set (sym, str->prec, str->assoc, + str->prec_location); else - { - lastsymbol->next = bp; - lastsymbol = bp; - } + symbol_precedence_set (str, sym->prec, sym->assoc, + sym->prec_location); + } +} - symtab[hashval] = bp; +static bool +symbol_check_alias_consistency_processor (void *this, + void *null ATTRIBUTE_UNUSED) +{ + symbol_check_alias_consistency (this); + return true; +} + + +/*-------------------------------------------------------------------. +| Assign a symbol number, and write the definition of the token name | +| into FDEFINES. Put in SYMBOLS. | +`-------------------------------------------------------------------*/ + +static inline bool +symbol_pack (symbol *this) +{ + aver (this->number != NUMBER_UNDEFINED); + if (this->class == nterm_sym) + this->number += ntokens; + else if (this->user_token_number == USER_NUMBER_HAS_STRING_ALIAS) + return true; + + symbols[this->number] = this; + return true; +} + +static bool +symbol_pack_processor (void *this, void *null ATTRIBUTE_UNUSED) +{ + return symbol_pack (this); +} + + +static void +user_token_number_redeclaration (int num, symbol *first, symbol *second) +{ + /* User token numbers are not assigned during the parsing, but in a + second step, via a traversal of the symbol table sorted on tag. + + However, error messages make more sense if we keep the first + declaration first. */ + if (location_cmp (first->location, second->location) > 0) + { + symbol* tmp = first; + first = second; + second = tmp; + } + complain_at (second->location, + _("user token number %d redeclaration for %s"), + num, second->tag); + complain_at (first->location, _("previous declaration for %s"), + first->tag); +} + +/*--------------------------------------------------. +| Put THIS in TOKEN_TRANSLATIONS if it is a token. | +`--------------------------------------------------*/ + +static inline bool +symbol_translation (symbol *this) +{ + /* Non-terminal? */ + if (this->class == token_sym + && this->user_token_number != USER_NUMBER_HAS_STRING_ALIAS) + { + /* A token which translation has already been set? */ + if (token_translations[this->user_token_number] != undeftoken->number) + user_token_number_redeclaration + (this->user_token_number, + symbols[token_translations[this->user_token_number]], + this); + + token_translations[this->user_token_number] = this->number; } - return bp; + return true; +} + +static bool +symbol_translation_processor (void *this, void *null ATTRIBUTE_UNUSED) +{ + return symbol_translation (this); +} + + +/*---------------------------------------. +| Symbol and semantic type hash tables. | +`---------------------------------------*/ + +/* Initial capacity of symbol and semantic type hash table. */ +#define HT_INITIAL_CAPACITY 257 + +static struct hash_table *symbol_table = NULL; +static struct hash_table *semantic_type_table = NULL; + +static inline bool +hash_compare_symbol (const symbol *m1, const symbol *m2) +{ + /* Since tags are unique, we can compare the pointers themselves. */ + return UNIQSTR_EQ (m1->tag, m2->tag); +} + +static inline bool +hash_compare_semantic_type (const semantic_type *m1, const semantic_type *m2) +{ + /* Since names are unique, we can compare the pointers themselves. */ + return UNIQSTR_EQ (m1->tag, m2->tag); +} + +static bool +hash_symbol_comparator (void const *m1, void const *m2) +{ + return hash_compare_symbol (m1, m2); +} + +static bool +hash_semantic_type_comparator (void const *m1, void const *m2) +{ + return hash_compare_semantic_type (m1, m2); +} + +static inline size_t +hash_symbol (const symbol *m, size_t tablesize) +{ + /* Since tags are unique, we can hash the pointer itself. */ + return ((uintptr_t) m->tag) % tablesize; +} + +static inline size_t +hash_semantic_type (const semantic_type *m, size_t tablesize) +{ + /* Since names are unique, we can hash the pointer itself. */ + return ((uintptr_t) m->tag) % tablesize; +} + +static size_t +hash_symbol_hasher (void const *m, size_t tablesize) +{ + return hash_symbol (m, tablesize); +} + +static size_t +hash_semantic_type_hasher (void const *m, size_t tablesize) +{ + return hash_semantic_type (m, tablesize); +} + +/*-------------------------------. +| Create the symbol hash table. | +`-------------------------------*/ + +void +symbols_new (void) +{ + symbol_table = hash_initialize (HT_INITIAL_CAPACITY, + NULL, + hash_symbol_hasher, + hash_symbol_comparator, + free); + semantic_type_table = hash_initialize (HT_INITIAL_CAPACITY, + NULL, + hash_semantic_type_hasher, + hash_semantic_type_comparator, + free); +} + + +/*----------------------------------------------------------------. +| Find the symbol named KEY, and return it. If it does not exist | +| yet, create it. | +`----------------------------------------------------------------*/ + +symbol * +symbol_from_uniqstr (const uniqstr key, location loc) +{ + symbol probe; + symbol *entry; + + probe.tag = key; + entry = hash_lookup (symbol_table, &probe); + + if (!entry) + { + /* First insertion in the hash. */ + aver (!symbols_sorted); + entry = symbol_new (key, loc); + if (!hash_insert (symbol_table, entry)) + xalloc_die (); + } + return entry; +} + + +/*-----------------------------------------------------------------------. +| Find the semantic type named KEY, and return it. If it does not exist | +| yet, create it. | +`-----------------------------------------------------------------------*/ + +semantic_type * +semantic_type_from_uniqstr (const uniqstr key) +{ + semantic_type probe; + semantic_type *entry; + + probe.tag = key; + entry = hash_lookup (semantic_type_table, &probe); + + if (!entry) + { + /* First insertion in the hash. */ + entry = semantic_type_new (key); + if (!hash_insert (semantic_type_table, entry)) + xalloc_die (); + } + return entry; +} + + +/*----------------------------------------------------------------. +| Find the symbol named KEY, and return it. If it does not exist | +| yet, create it. | +`----------------------------------------------------------------*/ + +symbol * +symbol_get (const char *key, location loc) +{ + return symbol_from_uniqstr (uniqstr_new (key), loc); +} + + +/*-----------------------------------------------------------------------. +| Find the semantic type named KEY, and return it. If it does not exist | +| yet, create it. | +`-----------------------------------------------------------------------*/ + +semantic_type * +semantic_type_get (const char *key) +{ + return semantic_type_from_uniqstr (uniqstr_new (key)); +} + + +/*------------------------------------------------------------------. +| Generate a dummy nonterminal, whose name cannot conflict with the | +| user's names. | +`------------------------------------------------------------------*/ + +symbol * +dummy_symbol_get (location loc) +{ + /* Incremented for each generated symbol. */ + static int dummy_count = 0; + static char buf[256]; + + symbol *sym; + + sprintf (buf, "$@%d", ++dummy_count); + sym = symbol_get (buf, loc); + sym->class = nterm_sym; + sym->number = nvars++; + return sym; +} + +bool +symbol_is_dummy (const symbol *sym) +{ + return sym->tag[0] == '@' || (sym->tag[0] == '$' && sym->tag[1] == '@'); } +/*-------------------. +| Free the symbols. | +`-------------------*/ void -free_symtab (void) +symbols_free (void) +{ + hash_free (symbol_table); + hash_free (semantic_type_table); + free (symbols); + free (symbols_sorted); +} + + +/*---------------------------------------------------------------. +| Look for undefined symbols, report an error, and consider them | +| terminals. | +`---------------------------------------------------------------*/ + +static int +symbols_cmp (symbol const *a, symbol const *b) +{ + return strcmp (a->tag, b->tag); +} + +static int +symbols_cmp_qsort (void const *a, void const *b) { + return symbols_cmp (*(symbol * const *)a, *(symbol * const *)b); +} + +static void +symbols_do (Hash_processor processor, void *processor_data) +{ + size_t count = hash_get_n_entries (symbol_table); + if (!symbols_sorted) + { + symbols_sorted = xnmalloc (count, sizeof *symbols_sorted); + hash_get_entries (symbol_table, (void**)symbols_sorted, count); + qsort (symbols_sorted, count, sizeof *symbols_sorted, + symbols_cmp_qsort); + } + { + size_t i; + for (i = 0; i < count; ++i) + processor (symbols_sorted[i], processor_data); + } +} + +/*--------------------------------------------------------------. +| Check that all the symbols are defined. Report any undefined | +| symbols and consider them nonterminals. | +`--------------------------------------------------------------*/ + +void +symbols_check_defined (void) +{ + symbols_do (symbol_check_defined_processor, NULL); +} + +/*------------------------------------------------------------------. +| Set TOKEN_TRANSLATIONS. Check that no two symbols share the same | +| number. | +`------------------------------------------------------------------*/ + +static void +symbols_token_translations_init (void) +{ + bool num_256_available_p = true; int i; - bucket *bp, *bptmp; /* JF don't use ptr after free */ - for (i = 0; i < TABSIZE; i++) + /* Find the highest user token number, and whether 256, the POSIX + preferred user token number for the error token, is used. */ + max_user_token_number = 0; + for (i = 0; i < ntokens; ++i) { - bp = symtab[i]; - while (bp) + symbol *this = symbols[i]; + if (this->user_token_number != USER_NUMBER_UNDEFINED) { - bptmp = bp->link; -#if 0 - /* This causes crashes because one string can appear more - than once. */ - if (bp->type_name) - XFREE (bp->type_name); -#endif - XFREE (bp); - bp = bptmp; + if (this->user_token_number > max_user_token_number) + max_user_token_number = this->user_token_number; + if (this->user_token_number == 256) + num_256_available_p = false; } } - XFREE (symtab); + + /* If 256 is not used, assign it to error, to follow POSIX. */ + if (num_256_available_p + && errtoken->user_token_number == USER_NUMBER_UNDEFINED) + errtoken->user_token_number = 256; + + /* Set the missing user numbers. */ + if (max_user_token_number < 256) + max_user_token_number = 256; + + for (i = 0; i < ntokens; ++i) + { + symbol *this = symbols[i]; + if (this->user_token_number == USER_NUMBER_UNDEFINED) + this->user_token_number = ++max_user_token_number; + if (this->user_token_number > max_user_token_number) + max_user_token_number = this->user_token_number; + } + + token_translations = xnmalloc (max_user_token_number + 1, + sizeof *token_translations); + + /* Initialize all entries for literal tokens to 2, the internal + token number for $undefined, which represents all invalid inputs. + */ + for (i = 0; i < max_user_token_number + 1; i++) + token_translations[i] = undeftoken->number; + symbols_do (symbol_translation_processor, NULL); +} + + +/*----------------------------------------------------------------. +| Assign symbol numbers, and write definition of token names into | +| FDEFINES. Set up vectors SYMBOL_TABLE, TAGS of symbols. | +`----------------------------------------------------------------*/ + +void +symbols_pack (void) +{ + symbols_do (symbol_check_alias_consistency_processor, NULL); + + symbols = xcalloc (nsyms, sizeof *symbols); + symbols_do (symbol_pack_processor, NULL); + + /* Aliases leave empty slots in symbols, so remove them. */ + { + int writei; + int readi; + int nsyms_old = nsyms; + for (writei = 0, readi = 0; readi < nsyms_old; readi += 1) + { + if (symbols[readi] == NULL) + { + nsyms -= 1; + ntokens -= 1; + } + else + { + symbols[writei] = symbols[readi]; + symbols[writei]->number = writei; + if (symbols[writei]->alias) + symbols[writei]->alias->number = writei; + writei += 1; + } + } + } + symbols = xnrealloc (symbols, nsyms, sizeof *symbols); + + symbols_token_translations_init (); + + if (startsymbol->class == unknown_sym) + fatal_at (startsymbol_location, + _("the start symbol %s is undefined"), + startsymbol->tag); + else if (startsymbol->class == token_sym) + fatal_at (startsymbol_location, + _("the start symbol %s is a token"), + startsymbol->tag); +} + + +/*--------------------------------------------------. +| Set default tagged/tagless %destructor/%printer. | +`--------------------------------------------------*/ + +void +default_tagged_destructor_set (code_props const *destructor) +{ + if (default_tagged_destructor.code) + { + complain_at (destructor->location, + _("redeclaration for default tagged %%destructor")); + complain_at (default_tagged_destructor.location, + _("previous declaration")); + } + default_tagged_destructor = *destructor; +} + +void +default_tagless_destructor_set (code_props const *destructor) +{ + if (default_tagless_destructor.code) + { + complain_at (destructor->location, + _("redeclaration for default tagless %%destructor")); + complain_at (default_tagless_destructor.location, + _("previous declaration")); + } + default_tagless_destructor = *destructor; +} + +void +default_tagged_printer_set (code_props const *printer) +{ + if (default_tagged_printer.code) + { + complain_at (printer->location, + _("redeclaration for default tagged %%printer")); + complain_at (default_tagged_printer.location, + _("previous declaration")); + } + default_tagged_printer = *printer; +} + +void +default_tagless_printer_set (code_props const *printer) +{ + if (default_tagless_printer.code) + { + complain_at (printer->location, + _("redeclaration for default tagless %%printer")); + complain_at (default_tagless_printer.location, + _("previous declaration")); + } + default_tagless_printer = *printer; }