the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
+#include <config.h>
#include "system.h"
#include <quotearg.h>
static bool start_flag = false;
merger_list *merge_functions;
-/* Has %union been seen? */
+/* Was %union seen? */
bool typed = false;
/* Should rules have a default precedence? */
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)
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);
| |
| 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. */
static symbol_list *grammar_end = NULL;
/* Append SYM to the grammar. */
-void
+static void
grammar_symbol_append (symbol *sym, location loc)
{
symbol_list *p = symbol_list_new (sym, loc);
grammar = p;
grammar_end = p;
+
+ /* A null SYM stands for an end of rule; it is not an actual
+ part of it. */
+ if (sym)
+ ++nritems;
}
/* The rule currently being defined, and the previous rule.
`----------------------------------------------*/
void
-grammar_rule_begin (symbol *lhs, location loc)
+grammar_current_rule_begin (symbol *lhs, location loc)
{
if (!start_flag)
{
/* Start a new rule and record its lhs. */
++nrules;
- ++nritems;
-
previous_rule_end = grammar_end;
grammar_symbol_append (lhs, 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;
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 rule R is properly defined. For instance, there |
+| should be no type clash on the default action. |
+`----------------------------------------------------------------*/
static void
-grammar_current_rule_check (void)
+grammar_rule_check (const symbol_list *r)
{
- symbol *lhs = current_rule->sym;
- char const *lhs_type = lhs->type_name;
- symbol *first_rhs = current_rule->next->sym;
+ /* Type check.
- /* 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;
+ If there is an action, then there is nothing we can do: the user
+ is allowed to shoot herself in the foot.
- /* Don't worry about the default action if $$ is untyped, since $$'s
+ Don't worry about the default action if $$ is untyped, since $$'s
value can't be used. */
- if (! lhs_type)
- return;
-
- /* If $$ is being set in default way, report if any type mismatch. */
- if (first_rhs)
+ if (!r->action && r->sym->type_name)
{
- const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : "";
- if (!UNIQSTR_EQ (lhs_type, rhs_type))
- warn_at (current_rule->location,
- _("type clash on default action: <%s> != <%s>"),
- lhs_type, rhs_type);
+ symbol *first_rhs = r->next->sym;
+ /* If $$ is being set in default way, report if any type mismatch. */
+ if (first_rhs)
+ {
+ char const *lhs_type = r->sym->type_name;
+ const char *rhs_type =
+ first_rhs->type_name ? first_rhs->type_name : "";
+ if (!UNIQSTR_EQ (lhs_type, rhs_type))
+ warn_at (r->location,
+ _("type clash on default action: <%s> != <%s>"),
+ lhs_type, rhs_type);
+ }
+ /* Warn if there is no default for $$ but we need one. */
+ else
+ warn_at (r->location,
+ _("empty rule for typed nonterminal, and no action"));
}
- /* Warn if there is no default for $$ but we need one. */
- else
- warn_at (current_rule->location,
- _("empty rule for typed nonterminal, and no action"));
+
+ /* Check that typed symbol values are used. */
+ {
+ symbol_list const *l = r;
+ int n = 0;
+ for (; l && l->sym; l = l->next, ++n)
+ if (! (l->used
+ || !l->sym->type_name
+ /* The default action, $$ = $1, `uses' both. */
+ || (!r->action && (n == 0 || n == 1))))
+ {
+ if (n)
+ warn_at (r->location, _("unused value: $%d"), n);
+ else
+ warn_at (r->location, _("unset value: $$"));
+ }
+ }
}
`-------------------------------------*/
void
-grammar_rule_end (location loc)
+grammar_current_rule_end (location loc)
{
/* Put an empty link in the list to mark the end of this rule */
grammar_symbol_append (NULL, grammar_end->location);
current_rule->location = loc;
- grammar_current_rule_check ();
+ grammar_rule_check (current_rule);
}
| rule. |
`-------------------------------------------------------------------*/
-void
+static void
grammar_midrule_action (void)
{
/* Since the action was written out with this rule's number, we must
{
if (current_rule->action)
grammar_midrule_action ();
- ++nritems;
grammar_symbol_append (sym, loc);
}
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;
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. */
projects / bison.git / blobdiff