/* Bison Action Scanner -*- C -*-
- Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008-2009 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
typedef struct
{
/* Index in symbol list. */
- unsigned index;
+ unsigned symbol_index;
/* Matched symbol id and loc. */
uniqstr id;
static variant *
variant_add (uniqstr id, location id_loc, unsigned symbol_index,
- char *cp, char *cp_end, bool exact_mode)
+ char *cp, char *cp_end, bool explicit_bracketing)
{
char *prefix_end;
prefix_end = find_prefix_end (id, cp, cp_end);
if (prefix_end &&
(prefix_end == cp_end ||
- (!exact_mode && is_dot_or_dash (*prefix_end))))
+ (!explicit_bracketing && is_dot_or_dash (*prefix_end))))
{
variant *r = variant_table_grow ();
- r->index = symbol_index;
+ r->symbol_index = symbol_index;
r->id = id;
r->loc = id_loc;
r->hidden_by = NULL;
return at_buf;
}
+static void
+show_sub_messages (const char* cp, bool explicit_bracketing,
+ int midrule_rhs_index, char dollar_or_at, bool is_warning)
+{
+ unsigned i;
+
+ for (i = 0; i < variant_count; ++i)
+ {
+ const variant *var = &variant_table[i];
+ const char *at_spec = get_at_spec (var->symbol_index);
+
+ if (var->err == 0)
+ {
+ if (is_warning)
+ warn_at (var->loc, _(" refers to: %c%s at %s"),
+ dollar_or_at, var->id, at_spec);
+ else
+ complain_at (var->loc, _(" refers to: %c%s at %s"),
+ dollar_or_at, var->id, at_spec);
+ }
+ else
+ {
+ static struct obstack msg_buf;
+ const char *tail = explicit_bracketing ? "" :
+ cp + strlen (var->id);
+ const char *id = var->hidden_by ? var->hidden_by->id :
+ var->id;
+ location id_loc = var->hidden_by ? var->hidden_by->loc :
+ var->loc;
+
+ /* Create the explanation message. */
+ obstack_init (&msg_buf);
+
+ obstack_fgrow1 (&msg_buf, " possibly meant: %c", dollar_or_at);
+ if (contains_dot_or_dash (id))
+ obstack_fgrow1 (&msg_buf, "[%s]", id);
+ else
+ obstack_sgrow (&msg_buf, id);
+ obstack_sgrow (&msg_buf, tail);
+
+ if (var->err & VARIANT_HIDDEN)
+ {
+ obstack_fgrow1 (&msg_buf, ", hiding %c", dollar_or_at);
+ if (contains_dot_or_dash (var->id))
+ obstack_fgrow1 (&msg_buf, "[%s]", var->id);
+ else
+ obstack_sgrow (&msg_buf, var->id);
+ obstack_sgrow (&msg_buf, tail);
+ }
+
+ obstack_fgrow1 (&msg_buf, " at %s", at_spec);
+
+ if (var->err & VARIANT_NOT_VISIBLE_FROM_MIDRULE)
+ obstack_fgrow1 (&msg_buf, ", cannot be accessed from "
+ "mid-rule action at $%d", midrule_rhs_index);
+
+ obstack_1grow (&msg_buf, '\0');
+ if (is_warning)
+ warn_at (id_loc, _("%s"), (char *) obstack_finish (&msg_buf));
+ else
+ complain_at (id_loc, _("%s"), (char *) obstack_finish (&msg_buf));
+ obstack_free (&msg_buf, 0);
+ }
+ }
+}
+
/* Returned from "parse_ref" when the reference
is inappropriate. */
#define INVALID_REF (INT_MIN)
/* Returned from "parse_ref" when the reference
- points to LHS ($$) of the current rule. */
+ points to LHS ($$) of the current rule or midrule. */
#define LHS_REF (INT_MIN + 1)
/* Parse named or positional reference. In case of positional
{
symbol_list *l;
char *cp_end;
- bool exact_mode;
- bool has_error;
- bool has_valid;
+ bool explicit_bracketing;
unsigned i;
+ unsigned valid_variants = 0;
+ unsigned valid_variant_index = 0;
if ('$' == *cp)
return LHS_REF;
continue;
cp_end = p;
- exact_mode = true;
+ explicit_bracketing = true;
}
else
{
continue;
cp_end = p;
- exact_mode = false;
+ explicit_bracketing = false;
}
/* Add all relevant variants. */
continue;
var = variant_add (l->content.sym->tag, l->sym_loc,
- symbol_index, cp, cp_end, exact_mode);
+ symbol_index, cp, cp_end, explicit_bracketing);
if (var && l->named_ref)
var->hidden_by = l->named_ref;
if (l->named_ref)
variant_add (l->named_ref->id, l->named_ref->loc,
- symbol_index, cp, cp_end, exact_mode);
+ symbol_index, cp, cp_end, explicit_bracketing);
}
}
/* Check errors. */
- has_error = false;
- has_valid = false;
for (i = 0; i < variant_count; ++i)
{
variant *var = &variant_table[i];
- unsigned symbol_index = var->index;
+ unsigned symbol_index = var->symbol_index;
/* Check visibility from mid-rule actions. */
if (midrule_rhs_index != 0
&& (symbol_index == 0 || midrule_rhs_index < symbol_index))
- {
- var->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE;
- has_error = true;
- }
+ var->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE;
/* Check correct bracketing. */
- if (!exact_mode && contains_dot_or_dash (var->id))
- {
- var->err |= VARIANT_BAD_BRACKETING;
- has_error = true;
- }
+ if (!explicit_bracketing && contains_dot_or_dash (var->id))
+ var->err |= VARIANT_BAD_BRACKETING;
/* Check using of hidden symbols. */
if (var->hidden_by)
- {
- var->err |= VARIANT_HIDDEN;
- has_error = true;
- }
+ var->err |= VARIANT_HIDDEN;
if (!var->err)
- has_valid = true;
+ {
+ valid_variant_index = i;
+ ++valid_variants;
+ }
}
- if (variant_count == 1 && has_valid)
- {
- /* The only "good" case is here. */
- unsigned symbol_index = variant_table[0].index;
- if (symbol_index == midrule_rhs_index)
- return LHS_REF;
- else
- return symbol_index;
- }
-
- /* Start complaining. */
-
- if (variant_count == 0)
- complain_at (text_loc, _("invalid reference: %s, symbol not found"),
- quote (text));
- else if (variant_count > 1 && !has_error)
- complain_at (text_loc, _("ambiguous reference: %s"),
- quote (text));
- else if (variant_count > 1 && has_valid && has_error)
- complain_at (text_loc, _("misleading reference: %s"),
- quote (text));
- else
- complain_at (text_loc, _("invalid reference: %s"),
- quote (text));
-
- for (i = 0; i < variant_count; ++i)
+ switch (valid_variants)
{
- const variant *var = &variant_table[i];
- const char *at_spec = get_at_spec (var->index);
-
- if (var->err == 0)
- complain_at (var->loc, _(" refers to: %c%s at %s"),
- dollar_or_at, var->id, at_spec);
+ case 0:
+ if (variant_count == 0)
+ {
+ if (explicit_bracketing || !ref_tail_fields)
+ complain_at (text_loc, _("unresolved reference: %s"),
+ quote(text));
+ else
+ {
+ unsigned len = ref_tail_fields - text;
+ char *str = strndup (text, len);
+ text_loc.end.column = text_loc.start.column + len;
+ complain_at (text_loc, _("unresolved reference: %s"),
+ quote (str));
+ free (str);
+ }
+ }
else
- {
- static struct obstack msg_buf;
- const char *tail = exact_mode ? "" :
- cp + strlen (var->id);
- const char *id = var->hidden_by ? var->hidden_by->id :
- var->id;
- location id_loc = var->hidden_by ? var->hidden_by->loc :
- var->loc;
-
- /* Create the explanation message. */
- obstack_init (&msg_buf);
-
- obstack_fgrow1 (&msg_buf, " possibly meant: %c", dollar_or_at);
- if (contains_dot_or_dash (id))
- obstack_fgrow1 (&msg_buf, "[%s]", id);
- else
- obstack_sgrow (&msg_buf, id);
- obstack_sgrow (&msg_buf, tail);
-
- if (var->err & VARIANT_HIDDEN)
- {
- obstack_fgrow1 (&msg_buf, ", hiding %c", dollar_or_at);
- if (contains_dot_or_dash (var->id))
- obstack_fgrow1 (&msg_buf, "[%s]", var->id);
- else
- obstack_sgrow (&msg_buf, var->id);
- obstack_sgrow (&msg_buf, tail);
- }
-
- obstack_fgrow1 (&msg_buf, " at %s", at_spec);
-
- if (var->err & VARIANT_NOT_VISIBLE_FROM_MIDRULE)
- obstack_fgrow1 (&msg_buf, ", cannot be accessed from "
- "mid-rule action at $%d", midrule_rhs_index);
-
- obstack_1grow (&msg_buf, '\0');
- complain_at (id_loc, _("%s"), (char *) obstack_finish (&msg_buf));
- obstack_free (&msg_buf, 0);
- }
+ {
+ complain_at (text_loc, _("invalid reference: %s"),
+ quote (text));
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, false);
+ }
+ return INVALID_REF;
+ case 1:
+ {
+ if (variant_count > 1)
+ {
+ warn_at (text_loc, _("misleading reference: %s"),
+ quote (text));
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, true);
+ }
+ {
+ unsigned symbol_index =
+ variant_table[valid_variant_index].symbol_index;
+ return (symbol_index == midrule_rhs_index) ? LHS_REF : symbol_index;
+ }
+ }
+ case 2:
+ default:
+ complain_at (text_loc, _("ambiguous reference: %s"),
+ quote (text));
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, false);
+ return INVALID_REF;
}
+ /* Not reachable. */
return INVALID_REF;
}
projects / bison.git / blobdiff