X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/52328c6e9941e9edde89fff880fc5dfdcc9429ee..affac6132ae6ee354e1497e456b5c81a0c84334f:/src/reader.c diff --git a/src/reader.c b/src/reader.c index 8b0e0359..b55b0fa9 100644 --- a/src/reader.c +++ b/src/reader.c @@ -1,7 +1,7 @@ /* Input parser for Bison - Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002 - Free Software Foundation, Inc. + Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002, 2003, + 2005 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -17,9 +17,10 @@ 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. */ + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. */ +#include #include "system.h" #include @@ -36,25 +37,28 @@ #include "symtab.h" static symbol_list *grammar = NULL; -static int start_flag = 0; +static bool start_flag = false; merger_list *merge_functions; -/* Nonzero if %union has been seen. */ -int typed = 0; +/* Was %union seen? */ +bool typed = false; + +/* Should rules have a default precedence? */ +bool default_prec = true; /*-----------------------. | Set the start symbol. | `-----------------------*/ void -grammar_start_symbol_set (symbol *s, location loc) +grammar_start_symbol_set (symbol *sym, location loc) { if (start_flag) complain_at (loc, _("multiple %s declarations"), "%start"); else { - start_flag = 1; - startsymbol = s; + start_flag = true; + startsymbol = sym; startsymbol_location = loc; } } @@ -71,36 +75,13 @@ prologue_augment (const char *prologue, location loc) struct obstack *oout = !typed ? &pre_prologue_obstack : &post_prologue_obstack; - obstack_fgrow1 (oout, "]b4_syncline([[%d]], [[", loc.start.line); + obstack_fgrow1 (oout, "]b4_syncline(%d, [[", loc.start.line); MUSCLE_OBSTACK_SGROW (oout, quotearg_style (c_quoting_style, loc.start.file)); obstack_sgrow (oout, "]])[\n"); obstack_sgrow (oout, prologue); } - - - -/*----------------------. -| Handle the epilogue. | -`----------------------*/ - -void -epilogue_augment (const char *epilogue, location loc) -{ - char *extension = NULL; - obstack_fgrow1 (&muscle_obstack, "]b4_syncline([[%d]], [[", loc.start.line); - MUSCLE_OBSTACK_SGROW (&muscle_obstack, - quotearg_style (c_quoting_style, loc.start.file)); - obstack_sgrow (&muscle_obstack, "]])[\n"); - obstack_sgrow (&muscle_obstack, epilogue); - obstack_1grow (&muscle_obstack, 0); - extension = obstack_finish (&muscle_obstack); - muscle_grow ("epilogue", extension, ""); - obstack_free (&muscle_obstack, extension); -} - - /*-------------------------------------------------------------------. @@ -123,12 +104,12 @@ get_merge_function (uniqstr name, uniqstr type, location loc) type = uniqstr_new (""); head.next = merge_functions; - for (syms = &head, n = 1; syms->next != NULL; syms = syms->next, n += 1) + for (syms = &head, n = 1; syms->next; syms = syms->next, n += 1) if (UNIQSTR_EQ (name, syms->next->name)) break; if (syms->next == NULL) { - MALLOC (syms->next, 1); + syms->next = xmalloc (sizeof syms->next[0]); syms->next->name = uniqstr_new (name); syms->next->type = uniqstr_new (type); syms->next->next = NULL; @@ -147,11 +128,8 @@ get_merge_function (uniqstr name, uniqstr type, location loc) void free_merger_functions (void) { - merger_list *L0; - if (! glr_parser) - return; - L0 = merge_functions; - while (L0 != NULL) + merger_list *L0 = merge_functions; + while (L0) { merger_list *L1 = L0->next; free (L0); @@ -169,17 +147,10 @@ free_merger_functions (void) | | | All actions are copied out, labelled by the rule number they apply | | to. | -| | -| Bison used to allow some %directives in the rules sections, but | -| this is no longer consider appropriate: (i) the documented grammar | -| doesn't claim it, (ii), it would promote bad style, (iii), error | -| recovery for %directives consists in skipping the junk until a `%' | -| is seen and helrp synchronizing. This scheme is definitely wrong | -| in the rules section. | `-------------------------------------------------------------------*/ /* The (currently) last symbol of GRAMMAR. */ -symbol_list *grammar_end = NULL; +static symbol_list *grammar_end = NULL; /* Append SYM to the grammar. */ void @@ -199,7 +170,7 @@ grammar_symbol_append (symbol *sym, location loc) CURRENT_RULE points to the first LHS of the current rule, while PREVIOUS_RULE_END points to the *end* of the previous rule (NULL). */ symbol_list *current_rule = NULL; -symbol_list *previous_rule_end = NULL; +static symbol_list *previous_rule_end = NULL; /*----------------------------------------------. @@ -213,7 +184,7 @@ grammar_rule_begin (symbol *lhs, location loc) { startsymbol = lhs; startsymbol_location = loc; - start_flag = 1; + start_flag = true; } /* Start a new rule and record its lhs. */ @@ -225,7 +196,6 @@ grammar_rule_begin (symbol *lhs, location loc) current_rule = grammar_end; /* Mark the rule's lhs as a nonterminal if not already so. */ - if (lhs->class == unknown_sym) { lhs->class = nterm_sym; @@ -236,39 +206,55 @@ grammar_rule_begin (symbol *lhs, location loc) complain_at (loc, _("rule given for %s, which is a token"), lhs->tag); } -/* Check that the last rule (CURRENT_RULE) is properly defined. For - instance, there should be no type clash on the default action. */ + +/*------------------------------------------------------------------. +| Check that the last rule (CURRENT_RULE) is properly defined. For | +| instance, there should be no type clash on the default action. | +`------------------------------------------------------------------*/ static void grammar_current_rule_check (void) { symbol *lhs = current_rule->sym; char const *lhs_type = lhs->type_name; - symbol *first_rhs = current_rule->next->sym; - /* If there is an action, then there is nothing we can do: the user - is allowed to shoot herself in the foot. */ - if (current_rule->action) - return; + /* Type check. - /* Don't worry about the default action if $$ is untyped, since $$'s - value can't be used. */ - if (! lhs_type) - return; + If there is an action, then there is nothing we can do: the user + is allowed to shoot herself in the foot. - /* If $$ is being set in default way, report if any type mismatch. */ - if (first_rhs) + Don't worry about the default action if $$ is untyped, since $$'s + value can't be used. */ + if (!current_rule->action && lhs_type) { - const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : ""; - if (!UNIQSTR_EQ (lhs_type, rhs_type)) + symbol *first_rhs = current_rule->next->sym; + /* If $$ is being set in default way, report if any type mismatch. */ + if (first_rhs) + { + const char *rhs_type = + first_rhs->type_name ? first_rhs->type_name : ""; + if (!UNIQSTR_EQ (lhs_type, rhs_type)) + warn_at (current_rule->location, + _("type clash on default action: <%s> != <%s>"), + lhs_type, rhs_type); + } + /* Warn if there is no default for $$ but we need one. */ + else warn_at (current_rule->location, - _("type clash on default action: <%s> != <%s>"), - lhs_type, rhs_type); + _("empty rule for typed nonterminal, and no action")); + } + + /* Check that all the symbol values are used. */ + if (typed) + { + symbol_list *l = current_rule; + int n = 1; + for (l = current_rule->next; l && l->sym; l = l->next, ++n) + /* The default action `uses' $1. */ + if (! (!current_rule->action && n == 1) + && l->sym->type_name && !l->used) + warn_at (current_rule->location, _("unused value: $%d"), n); } - /* Warn if there is no default for $$ but we need one. */ - else - warn_at (current_rule->location, - _("empty rule for typed nonterminal, and no action")); } @@ -407,8 +393,8 @@ packgram (void) rule_number ruleno = 0; symbol_list *p = grammar; - CALLOC (ritem, nritems); - CALLOC (rules, nrules); + ritem = xnmalloc (nritems, sizeof *ritem); + rules = xnmalloc (nrules, sizeof *rules); while (p) { @@ -417,12 +403,14 @@ packgram (void) rules[ruleno].number = ruleno; rules[ruleno].lhs = p->sym; rules[ruleno].rhs = ritem + itemno; + rules[ruleno].prec = NULL; + rules[ruleno].dprec = p->dprec; + rules[ruleno].merger = p->merger; + rules[ruleno].precsym = NULL; rules[ruleno].location = p->location; rules[ruleno].useful = true; rules[ruleno].action = p->action; rules[ruleno].action_location = p->action_location; - rules[ruleno].dprec = p->dprec; - rules[ruleno].merger = p->merger; p = p->next; while (p && p->sym) @@ -432,7 +420,7 @@ packgram (void) ritem[itemno++] = symbol_number_as_item_number (p->sym->number); /* A rule gets by default the precedence and associativity of the last token in it. */ - if (p->sym->class == token_sym) + if (p->sym->class == token_sym && default_prec) rules[ruleno].prec = p->sym; if (p) p = p->next; @@ -492,8 +480,7 @@ reader (void) obstack_init (&pre_prologue_obstack); obstack_init (&post_prologue_obstack); - finput = xfopen (grammar_file, "r"); - gram_in = finput; + gram_in = xfopen (grammar_file, "r"); gram__flex_debug = trace_flag & trace_scan; gram_debug = trace_flag & trace_parse; @@ -541,7 +528,7 @@ reader (void) if (! (nsyms <= SYMBOL_NUMBER_MAXIMUM && nsyms == ntokens + nvars)) abort (); - xfclose (finput); + xfclose (gram_in); /* Assign the symbols their symbol numbers. Write #defines for the token symbols into FDEFINES if requested. */