X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/872b52bc24b5590ac8bdec7db882cdbefc0ec3ff..7439c5c0f94940884e998c06b910476c6f6145b5:/src/scan-code.l diff --git a/src/scan-code.l b/src/scan-code.l index 78cf8394..56cd7825 100644 --- a/src/scan-code.l +++ b/src/scan-code.l @@ -17,7 +17,7 @@ You should have received a copy of the GNU General Public License along with this program. If not, see . */ -%option debug nodefault nounput noyywrap never-interactive +%option debug nodefault noinput nounput noyywrap never-interactive %option prefix="code_" outfile="lex.yy.c" %{ @@ -307,7 +307,7 @@ contains_dot_or_dash (const char* p) typedef struct { /* Index in symbol list. */ - unsigned index; + unsigned symbol_index; /* Matched symbol id and loc. */ uniqstr id; @@ -338,7 +338,7 @@ static unsigned variant_table_size = 0; static unsigned variant_count = 0; static variant * -variant_table_grow () +variant_table_grow (void) { ++variant_count; if (variant_count > variant_table_size) @@ -351,6 +351,14 @@ variant_table_grow () return &variant_table[variant_count - 1]; } +static void +variant_table_free (void) +{ + free (variant_table); + variant_table = 0; + variant_table_size = variant_count = 0; +} + static char * find_prefix_end (const char *prefix, char *begin, char *end) { @@ -367,20 +375,20 @@ find_prefix_end (const char *prefix, char *begin, char *end) } static variant * -variant_add (uniqstr id, location loc, unsigned index, - char *cp, char *cp_end, bool exact_mode) +variant_add (uniqstr id, location id_loc, unsigned symbol_index, + 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 = index; + r->symbol_index = symbol_index; r->id = id; - r->loc = loc; + r->loc = id_loc; r->hidden_by = NULL; r->err = 0; return r; @@ -390,38 +398,113 @@ variant_add (uniqstr id, location loc, unsigned index, } static const char * -get_at_spec(unsigned index) +get_at_spec(unsigned symbol_index) { static char at_buf[20]; - if (index == 0) + if (symbol_index == 0) strcpy (at_buf, "$$"); else - snprintf (at_buf, sizeof at_buf, "$%u", index); + snprintf (at_buf, sizeof at_buf, "$%u", symbol_index); 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 indent) +{ + 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_indent (var->loc, &indent, _("refers to: %c%s at %s"), + dollar_or_at, var->id, at_spec); + else + complain_at_indent (var->loc, &indent, _("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) + { + const char *format = + _(", cannot be accessed from mid-rule action at $%d"); + obstack_fgrow1 (&msg_buf, format, midrule_rhs_index); + } + + obstack_1grow (&msg_buf, '\0'); + if (is_warning) + warn_at_indent (id_loc, &indent, "%s", + (char *) obstack_finish (&msg_buf)); + else + complain_at_indent (id_loc, &indent, "%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) +/* Sub-messages indent. */ +#define SUB_INDENT (4) + /* Parse named or positional reference. In case of positional references, can return negative values for $-n "deep" stack accesses. */ static long int parse_ref (char *cp, symbol_list *rule, int rule_length, - int midrule_rhs_index, char *text, location loc, + int midrule_rhs_index, char *text, location text_loc, char dollar_or_at) { symbol_list *l; char *cp_end; - bool exact_mode; - bool has_error; - bool has_valid; + bool explicit_bracketing; unsigned i; + unsigned valid_variants = 0; + unsigned valid_variant_index = 0; if ('$' == *cp) return LHS_REF; @@ -433,7 +516,8 @@ parse_ref (char *cp, symbol_list *rule, int rule_length, return num; else { - complain_at (loc, _("integer out of range: %s"), quote (text)); + complain_at (text_loc, _("integer out of range: %s"), + quote (text)); return INVALID_REF; } } @@ -446,7 +530,7 @@ parse_ref (char *cp, symbol_list *rule, int rule_length, continue; cp_end = p; - exact_mode = true; + explicit_bracketing = true; } else { @@ -462,140 +546,117 @@ parse_ref (char *cp, symbol_list *rule, int rule_length, continue; cp_end = p; - exact_mode = false; + explicit_bracketing = false; } /* Add all relevant variants. */ { - unsigned index; + unsigned symbol_index; variant_count = 0; - for (index = 0, l = rule; !symbol_list_null (l); ++index, l = l->next) + for (symbol_index = 0, l = rule; !symbol_list_null (l); + ++symbol_index, l = l->next) { - variant *variant; + variant *var; if (l->content_type != SYMLIST_SYMBOL) continue; - variant = variant_add (l->content.sym->tag, l->sym_loc, index, - cp, cp_end, exact_mode); - - if (variant && l->named_ref) - variant->hidden_by = l->named_ref; + var = variant_add (l->content.sym->tag, l->sym_loc, + 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, index, - cp, cp_end, exact_mode); + variant_add (l->named_ref->id, l->named_ref->loc, + symbol_index, cp, cp_end, explicit_bracketing); } } /* Check errors. */ - has_error = false; - has_valid = false; for (i = 0; i < variant_count; ++i) { - variant *variant = &variant_table[i]; - unsigned index = variant->index; + variant *var = &variant_table[i]; + unsigned symbol_index = var->symbol_index; /* Check visibility from mid-rule actions. */ if (midrule_rhs_index != 0 - && (index == 0 || midrule_rhs_index < index)) - { - variant->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE; - has_error = true; - } + && (symbol_index == 0 || midrule_rhs_index < symbol_index)) + var->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE; /* Check correct bracketing. */ - if (!exact_mode && contains_dot_or_dash (variant->id)) - { - variant->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 (variant->hidden_by) - { - variant->err |= VARIANT_HIDDEN; - has_error = true; - } - - if (!variant->err) - has_valid = true; + if (var->hidden_by) + var->err |= VARIANT_HIDDEN; + + if (!var->err) + { + valid_variant_index = i; + ++valid_variants; + } } - if (variant_count == 1 && has_valid) + switch (valid_variants) { - /* The only "good" case is here. */ - unsigned index = variant_table[0].index; - if (index == midrule_rhs_index) - return LHS_REF; - else - return index; - } - - /* Start complaining. */ - - if (variant_count == 0) - complain_at (loc, _("invalid reference: %s, symbol not found"), - quote (text)); - else if (variant_count > 1 && !has_error) - complain_at (loc, _("ambiguous reference: %s"), - quote (text)); - else if (variant_count > 1 && has_valid && has_error) - complain_at (loc, _("misleading reference: %s"), - quote (text)); - else - complain_at (loc, _("invalid reference: %s"), - quote (text)); - - for (i = 0; i < variant_count; ++i) - { - const variant *variant = &variant_table[i]; - const char *at_spec = get_at_spec (variant->index); - - if (variant->err == 0) - complain_at (variant->loc, _(" refers to: %c%s at %s"), - dollar_or_at, variant->id, at_spec); - else - { - static struct obstack msg_buf; - const char *tail = exact_mode ? "" : - cp + strlen (variant->id); - const char *id = variant->hidden_by ? variant->hidden_by->id : - variant->id; - location loc = variant->hidden_by ? variant->hidden_by->loc : - variant->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 (variant->err & VARIANT_HIDDEN) - { - obstack_fgrow1 (&msg_buf, ", hiding %c", dollar_or_at); - if (contains_dot_or_dash (variant->id)) - obstack_fgrow1 (&msg_buf, "[%s]", variant->id); - else - obstack_sgrow (&msg_buf, variant->id); - obstack_sgrow (&msg_buf, tail); - } - - obstack_fgrow1 (&msg_buf, " at %s", at_spec); - - if (variant->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 (loc, _("%s"), (char *) obstack_finish (&msg_buf)); - obstack_free (&msg_buf, 0); - } + case 0: + { + unsigned len = (explicit_bracketing || !ref_tail_fields) ? + cp_end - cp : ref_tail_fields - cp; + unsigned indent = 0; + + complain_at_indent (text_loc, &indent, _("invalid reference: %s"), + quote (text)); + indent += SUB_INDENT; + if (midrule_rhs_index) + { + const char *format = + _("symbol not found in production before $%d: %.*s"); + complain_at_indent (rule->location, &indent, format, + midrule_rhs_index, len, cp); + } + else + { + const char *format = + _("symbol not found in production: %.*s"); + complain_at_indent (rule->location, &indent, format, + len, cp); + } + + if (variant_count > 0) + show_sub_messages (cp, explicit_bracketing, midrule_rhs_index, + dollar_or_at, false, indent); + return INVALID_REF; + } + case 1: + { + unsigned indent = 0; + if (variant_count > 1) + { + warn_at_indent (text_loc, &indent, _("misleading reference: %s"), + quote (text)); + show_sub_messages (cp, explicit_bracketing, midrule_rhs_index, + dollar_or_at, true, indent + SUB_INDENT); + } + { + unsigned symbol_index = + variant_table[valid_variant_index].symbol_index; + return (symbol_index == midrule_rhs_index) ? LHS_REF : symbol_index; + } + } + case 2: + default: + { + unsigned indent = 0; + complain_at_indent (text_loc, &indent, _("ambiguous reference: %s"), + quote (text)); + show_sub_messages (cp, explicit_bracketing, midrule_rhs_index, + dollar_or_at, false, indent + SUB_INDENT); + return INVALID_REF; + } } + /* Not reachable. */ return INVALID_REF; } @@ -827,14 +888,14 @@ code_props_symbol_action_init (code_props *self, char const *code, void code_props_rule_action_init (code_props *self, char const *code, location code_loc, symbol_list *rule, - named_ref *named_ref) + named_ref *name) { self->kind = CODE_PROPS_RULE_ACTION; self->code = code; self->location = code_loc; self->is_value_used = false; self->rule = rule; - self->named_ref = named_ref; + self->named_ref = name; } void @@ -866,6 +927,8 @@ void code_scanner_free (void) { obstack_free (&obstack_for_string, 0); + variant_table_free (); + /* Reclaim Flex's buffers. */ yylex_destroy (); }