/* Input parser for Bison
- Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002, 2003,
- 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000-2003, 2005-2007,
+ 2009-2012 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
#include "files.h"
#include "getargs.h"
#include "gram.h"
-#include "muscle_tab.h"
+#include "muscle-tab.h"
#include "reader.h"
#include "symlist.h"
#include "symtab.h"
p = grammar_symbol_append (lhs, loc);
if (lhs_name)
- assign_named_ref(p, lhs_name);
+ assign_named_ref (p, named_ref_copy (lhs_name));
current_rule = grammar_end;
/*----------------------------------------------------------------------.
| A symbol should be used if either: |
| 1. It has a destructor. |
-| 2. --warnings=midrule-values and the symbol is a mid-rule symbol |
-| (i.e., the generated LHS replacing a mid-rule action) that was |
-| assigned to or used, as in "exp: { $$ = 1; } { $$ = $1; }". |
+| 2. The symbol is a mid-rule symbol (i.e., the generated LHS |
+| replacing a mid-rule action) that was assigned to or used, as in |
+| "exp: { $$ = 1; } { $$ = $1; }". |
`----------------------------------------------------------------------*/
static bool
-symbol_should_be_used (symbol_list const *s)
+symbol_should_be_used (symbol_list const *s, bool *midrule_warning)
{
if (symbol_destructor_get (s->content.sym)->code)
return true;
- if (warnings_flag & warnings_midrule_values)
- return ((s->midrule && s->midrule->action_props.is_value_used)
- || (s->midrule_parent_rule
- && symbol_list_n_get (s->midrule_parent_rule,
- s->midrule_parent_rhs_index)
- ->action_props.is_value_used));
+ if ((s->midrule && s->midrule->action_props.is_value_used)
+ || (s->midrule_parent_rule
+ && symbol_list_n_get (s->midrule_parent_rule,
+ s->midrule_parent_rhs_index)
+ ->action_props.is_value_used))
+ {
+ *midrule_warning = true;
+ return true;
+ }
return false;
}
symbol_list const *l = r;
int n = 0;
for (; l && l->content.sym; l = l->next, ++n)
- if (! (l->action_props.is_value_used
- || !symbol_should_be_used (l)
- /* The default action, $$ = $1, `uses' both. */
- || (!r->action_props.code && (n == 0 || n == 1))))
- {
- if (n)
- warn_at (r->location, _("unused value: $%d"), n);
- else
- warn_at (r->location, _("unset value: $$"));
- }
+ {
+ bool midrule_warning = false;
+ if (!l->action_props.is_value_used
+ && symbol_should_be_used (l, &midrule_warning)
+ /* The default action, $$ = $1, `uses' both. */
+ && (r->action_props.code || (n != 0 && n != 1)))
+ {
+ void (*warn_at_ptr)(location, char const*, ...) =
+ midrule_warning ? midrule_value_at : warn_at;
+ if (n)
+ warn_at_ptr (r->location, _("unused value: $%d"), n);
+ else
+ warn_at_ptr (r->location, _("unset value: $$"));
+ }
+ }
}
+
+ /* See comments in grammar_current_rule_prec_set for how POSIX
+ mandates this complaint. It's only for identifiers, so skip
+ it for char literals and strings, which are always tokens. */
+ if (r->ruleprec
+ && r->ruleprec->tag[0] != '\'' && r->ruleprec->tag[0] != '"'
+ && !r->ruleprec->declared && !r->ruleprec->prec)
+ warn_at (r->location, _("token for %%prec is not defined: %s"),
+ r->ruleprec->tag);
}
void
grammar_current_rule_prec_set (symbol *precsym, location loc)
{
+ /* POSIX says that any identifier is a nonterminal if it does not
+ appear on the LHS of a grammar rule and is not defined by %token
+ or by one of the directives that assigns precedence to a token. We
+ ignore this here because the only kind of identifier that POSIX
+ allows to follow a %prec is a token and because assuming it's a
+ token now can produce more logical error messages. Nevertheless,
+ grammar_rule_check does obey what we believe is the real intent of
+ POSIX here: that an error be reported for any identifier that
+ appears after %prec but that is not defined separately as a
+ token. */
symbol_class_set (precsym, token_sym, loc, false);
if (current_rule->ruleprec)
complain_at (loc, _("only one %s allowed per rule"), "%prec");
char *lr_type;
/* IELR would be a better default, but LALR is historically the
default. */
- muscle_percent_define_default ("lr.type", "LALR");
+ muscle_percent_define_default ("lr.type", "lalr");
lr_type = muscle_percent_define_get ("lr.type");
- if (0 != strcmp (lr_type, "canonical LR"))
- muscle_percent_define_default ("lr.default-reductions", "all");
+ if (0 != strcmp (lr_type, "canonical-lr"))
+ muscle_percent_define_default ("lr.default-reductions", "most");
else
muscle_percent_define_default ("lr.default-reductions", "accepting");
free (lr_type);
/* Check %define front-end variables. */
{
static char const * const values[] = {
- "lr.type", "LALR", "IELR", "canonical LR", NULL,
- "lr.default-reductions", "all", "consistent", "accepting", NULL,
+ "lr.type", "lalr", "ielr", "canonical-lr", NULL,
+ "lr.default-reductions", "most", "consistent", "accepting", NULL,
NULL
};
muscle_percent_define_check_values (values);
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