X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/13cdf208ed0f643dd00262ef87fcc7b83dab27a6..e9690142325711b320ef444768fdd40a087d02f7:/src/scan-code.l diff --git a/src/scan-code.l b/src/scan-code.l index aaaaaed0..cf4e7614 100644 --- a/src/scan-code.l +++ b/src/scan-code.l @@ -1,6 +1,6 @@ /* Bison Action Scanner -*- C -*- - Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc. + Copyright (C) 2006-2011 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -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" %{ @@ -48,7 +48,7 @@ YY_DECL; #define YY_USER_ACTION location_compute (loc, &loc->end, yytext, yyleng); static void handle_action_dollar (symbol_list *rule, char *cp, - location dollar_loc); + location dollar_loc); static void handle_action_at (symbol_list *rule, char *cp, location at_loc); /* A string to be pushed to obstack after dollar/at has been handled. */ @@ -76,17 +76,17 @@ static bool untyped_var_seen; /* POSIX says that a tag must be both an id and a C union member, but historically almost any character is allowed in a tag. We disallow NUL and newline, as this simplifies our implementation. */ -tag [^\0\n>]+ +tag [^\0\n>]+ /* Zero or more instances of backslash-newline. Following GCC, allow white space between the backslash and the newline. */ -splice (\\[ \f\t\v]*\n)* +splice (\\[ \f\t\v]*\n)* /* C style identifier. Must start with letter. Will be used for named symbol references. Shall be kept synchronized with scan-gram.l "letter" and "id". */ -letter [-.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] -id {letter}({letter}|[0-9])* +letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] +id {letter}({letter}|[-0-9])* ref -?[0-9]+|{id}|"["{id}"]"|"$" %% @@ -112,8 +112,8 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" is expected to return only once. This initialization is therefore done once per action to translate. */ aver (sc_context == SC_SYMBOL_ACTION - || sc_context == SC_RULE_ACTION - || sc_context == INITIAL); + || sc_context == SC_RULE_ACTION + || sc_context == INITIAL); BEGIN sc_context; %} @@ -133,8 +133,8 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" { - "\n" STRING_GROW; BEGIN sc_context; - {splice} STRING_GROW; + "\n" STRING_GROW; BEGIN sc_context; + {splice} STRING_GROW; } @@ -144,17 +144,17 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" { - {splice}|\\{splice}. STRING_GROW; + {splice}|\\{splice}. STRING_GROW; } { - "'" STRING_GROW; BEGIN sc_context; + "'" STRING_GROW; BEGIN sc_context; } { - "\"" STRING_GROW; BEGIN sc_context; + "\"" STRING_GROW; BEGIN sc_context; } @@ -228,9 +228,9 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" if (outer_brace && !yacc_flag && language_prio == default_prio && skeleton_prio == default_prio && need_semicolon && ! in_cpp) { - warn_at (*loc, _("a `;' might be needed at the end of action code")); - warn_at (*loc, _("future versions of Bison will not add the `;'")); - obstack_1grow (&obstack_for_string, ';'); + warn_at (*loc, _("a `;' might be needed at the end of action code")); + warn_at (*loc, _("future versions of Bison will not add the `;'")); + obstack_1grow (&obstack_for_string, ';'); } STRING_GROW; @@ -246,7 +246,20 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" {splice} STRING_GROW; [\n\r] STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false; [ \t\f] STRING_GROW; - . STRING_GROW; need_semicolon = true; + + /* YYFAIL is undocumented and was formally deprecated in Bison + 2.4.2. */ + YYFAIL { + STRING_GROW; need_semicolon = true; + warn_at (*loc, _("use of YYFAIL, which is deprecated and will be" + " removed")); + } + + /* The sole purpose of this is to make sure identifiers that merely + contain YYFAIL don't produce the above warning. */ + [A-Za-z_][0-9A-Za-z_]* STRING_GROW; need_semicolon = true; + + . STRING_GROW; need_semicolon = true; } @@ -268,20 +281,20 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$" <*> { - \$ obstack_sgrow (&obstack_for_string, "$]["); - \@ obstack_sgrow (&obstack_for_string, "@@"); - \[ obstack_sgrow (&obstack_for_string, "@{"); - \] obstack_sgrow (&obstack_for_string, "@}"); + \$ obstack_sgrow (&obstack_for_string, "$]["); + \@ obstack_sgrow (&obstack_for_string, "@@"); + \[ obstack_sgrow (&obstack_for_string, "@{"); + \] obstack_sgrow (&obstack_for_string, "@}"); } /*-----------------------------------------------------. | By default, grow the string obstack with the input. | `-----------------------------------------------------*/ -<*>.|\n STRING_GROW; +<*>.|\n STRING_GROW; /* End of processing. */ -<*><> { +<*><> { STRING_FINISH; return last_string; } @@ -307,7 +320,7 @@ 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; @@ -338,24 +351,23 @@ 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) { while (variant_count > variant_table_size) - variant_table_size = 2 * variant_table_size + 3; + variant_table_size = 2 * variant_table_size + 3; variant_table = xnrealloc (variant_table, variant_table_size, - sizeof *variant_table); + sizeof *variant_table); } return &variant_table[variant_count - 1]; } static void -variant_table_free () +variant_table_free (void) { - if (variant_table) - free (variant_table); + free (variant_table); variant_table = 0; variant_table_size = variant_count = 0; } @@ -376,20 +388,20 @@ 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; @@ -399,38 +411,113 @@ 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, - char dollar_or_at) + 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; @@ -439,12 +526,13 @@ parse_ref (char *cp, symbol_list *rule, int rule_length, { long int num = strtol (cp, &cp, 10); if (1 - INT_MAX + rule_length <= num && num <= rule_length) - return num; + return num; else - { - complain_at (loc, _("integer out of range: %s"), quote (text)); - return INVALID_REF; - } + { + complain_at (text_loc, _("integer out of range: %s"), + quote (text)); + return INVALID_REF; + } } if ('[' == *cp) @@ -452,159 +540,146 @@ parse_ref (char *cp, symbol_list *rule, int rule_length, /* Ignore the brackets. */ char *p; for (p = ++cp; *p != ']'; ++p) - continue; + continue; cp_end = p; - exact_mode = true; + explicit_bracketing = true; } else { /* Take all characters of the name. */ char* p; for (p = cp; *p; ++p) - if (is_dot_or_dash (*p)) - { - ref_tail_fields = p; - break; - } + if (is_dot_or_dash (*p)) + { + ref_tail_fields = p; + break; + } for (p = cp; *p; ++p) - continue; + 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; - 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; - - if (l->named_ref) - variant_add (l->named_ref->id, l->named_ref->loc, index, - cp, cp_end, exact_mode); + variant *var; + if (l->content_type != SYMLIST_SYMBOL) + continue; + + 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, + 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 (len == 0) + { + location sym_loc = text_loc; + sym_loc.start.column += 1; + sym_loc.end = sym_loc.start; + const char *format = + _("syntax error after `%c', expecting integer, letter," + " `_', `[', or `$'"); + complain_at_indent (sym_loc, &indent, format, dollar_or_at); + } + else 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; } @@ -648,19 +723,19 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc) { type_name = ++cp; while (*cp != '>') - ++cp; + ++cp; /* The '>' symbol will be later replaced by '\0'. Original - 'text' is needed for error messages. */ + 'text' is needed for error messages. */ gt_ptr = cp; ++cp; if (untyped_var_seen) - complain_at (dollar_loc, _("explicit type given in untyped grammar")); + complain_at (dollar_loc, _("explicit type given in untyped grammar")); tag_seen = true; } n = parse_ref (cp, effective_rule, effective_rule_length, - rule->midrule_parent_rhs_index, text, dollar_loc, '$'); + rule->midrule_parent_rhs_index, text, dollar_loc, '$'); if (gt_ptr) *gt_ptr = '\0'; @@ -672,54 +747,54 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc) case LHS_REF: if (!type_name) - type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0); + type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0); if (!type_name) - { - if (union_seen | tag_seen) - { - if (rule->midrule_parent_rule) - complain_at (dollar_loc, - _("$$ for the midrule at $%d of `%s'" - " has no declared type"), - rule->midrule_parent_rhs_index, - effective_rule->content.sym->tag); - else - complain_at (dollar_loc, _("$$ of `%s' has no declared type"), - rule->content.sym->tag); - } - else - untyped_var_seen = true; - type_name = ""; - } + { + if (union_seen | tag_seen) + { + if (rule->midrule_parent_rule) + complain_at (dollar_loc, + _("$$ for the midrule at $%d of `%s'" + " has no declared type"), + rule->midrule_parent_rhs_index, + effective_rule->content.sym->tag); + else + complain_at (dollar_loc, _("$$ of `%s' has no declared type"), + rule->content.sym->tag); + } + else + untyped_var_seen = true; + type_name = ""; + } obstack_fgrow1 (&obstack_for_string, - "]b4_lhs_value([%s])[", type_name); + "]b4_lhs_value([%s])[", type_name); rule->action_props.is_value_used = true; break; default: if (max_left_semantic_context < 1 - n) - max_left_semantic_context = 1 - n; + max_left_semantic_context = 1 - n; if (!type_name && 0 < n) - type_name = - symbol_list_n_type_name_get (effective_rule, dollar_loc, n); + type_name = + symbol_list_n_type_name_get (effective_rule, dollar_loc, n); if (!type_name) - { - if (union_seen | tag_seen) - complain_at (dollar_loc, _("$%s of `%s' has no declared type"), - cp, effective_rule->content.sym->tag); - else - untyped_var_seen = true; - type_name = ""; - } + { + if (union_seen | tag_seen) + complain_at (dollar_loc, _("$%s of `%s' has no declared type"), + cp, effective_rule->content.sym->tag); + else + untyped_var_seen = true; + type_name = ""; + } obstack_fgrow3 (&obstack_for_string, - "]b4_rhs_value(%d, %d, [%s])[", - effective_rule_length, n, type_name); + "]b4_rhs_value(%d, %d, [%s])[", + effective_rule_length, n, type_name); if (n > 0) - symbol_list_n_get (effective_rule, n)->action_props.is_value_used = - true; + symbol_list_n_get (effective_rule, n)->action_props.is_value_used = + true; break; } } @@ -752,7 +827,7 @@ handle_action_at (symbol_list *rule, char *text, location at_loc) muscle_percent_define_ensure("locations", at_loc, true); n = parse_ref (cp, effective_rule, effective_rule_length, - rule->midrule_parent_rhs_index, text, at_loc, '@'); + rule->midrule_parent_rhs_index, text, at_loc, '@'); switch (n) { case INVALID_REF: @@ -764,7 +839,7 @@ handle_action_at (symbol_list *rule, char *text, location at_loc) default: obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[", - effective_rule_length, n); + effective_rule_length, n); break; } } @@ -811,7 +886,7 @@ code_props const code_props_none = CODE_PROPS_NONE_INIT; void code_props_plain_init (code_props *self, char const *code, - location code_loc) + location code_loc) { self->kind = CODE_PROPS_PLAIN; self->code = code; @@ -836,14 +911,15 @@ 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, bool is_predicate) { 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; + self->is_predicate = is_predicate; } void