Index: ChangeLog from Akim Demaille * src/reader.c (grammar_current_rule_check): Also check that $$ is used. Take the rule to check as argument, hence rename as... (grammar_rule_check): this. * src/reader.h, src/reader.c (grammar_rule_begin, grammar_rule_end): Rename as... (grammar_rule_begin, grammar_rule_end): these, for consistency. (grammar_midrule_action, grammar_symbol_append): Now static. * tests/torture.at (input): Don't rely on the default action being always performed. * tests/calc.at: "Set" $$ even when the action is "cut" with YYERROR or other. * tests/actions.at (Exotic Dollars): Instead of using unused values, check that the warning is issued. Index: NEWS =================================================================== RCS file: /cvsroot/bison/bison/NEWS,v retrieving revision 1.138 diff -u -r1.138 NEWS --- NEWS 23 Dec 2005 00:13:11 -0000 1.138 +++ NEWS 27 Dec 2005 17:37:20 -0000 @@ -7,13 +7,13 @@ Typed right-hand side symbols whose value are not used are reported. For instance: - exp: exp "?" exp ":" exp { $$ = $1 ? $1 : $3; } + exp: exp "?" exp ":" exp { $1 ? $1 : $3; } | exp "+" exp ; - will trigger a warning about $5 of the first rule, and $3 in the - second ($1 is copied to $$ by the default rule). This example - most likely contains two errors, and should be rewritten as: + will trigger a warning about $$ and $5 in the first rule, and $3 in + the second ($1 is copied to $$ by the default rule). This example + most likely contains three errors, and should be rewritten as: exp: exp "?" exp ":" exp { $$ = $1 ? $3 : $5; } | exp "+" exp { $$ = $1 + $3; } @@ -22,7 +22,7 @@ However, if the original actions were really intended, the warnings can be suppressed by letting Bison believe the values are used, e.g.: - exp: exp "?" exp ":" exp { $$ = $1 ? $1 : $3; (void) $5; } + exp: exp "?" exp ":" exp { $1 ? $1 : $3; (void) ($$, $5); } | exp "+" exp { $$ = $1; (void) $3; } ; Index: src/parse-gram.y =================================================================== RCS file: /cvsroot/bison/bison/src/parse-gram.y,v retrieving revision 1.64 diff -u -r1.64 parse-gram.y --- src/parse-gram.y 9 Dec 2005 23:51:26 -0000 1.64 +++ src/parse-gram.y 27 Dec 2005 17:37:27 -0000 @@ -396,14 +396,14 @@ ; rhses.1: - rhs { grammar_rule_end (@1); } -| rhses.1 "|" rhs { grammar_rule_end (@3); } + rhs { grammar_current_rule_end (@1); } +| rhses.1 "|" rhs { grammar_current_rule_end (@3); } | rhses.1 ";" ; rhs: /* Nothing. */ - { grammar_rule_begin (current_lhs, current_lhs_location); } + { grammar_current_rule_begin (current_lhs, current_lhs_location); } | rhs symbol { grammar_current_rule_symbol_append ($2, @2); } | rhs action Index: src/reader.c =================================================================== RCS file: /cvsroot/bison/bison/src/reader.c,v retrieving revision 1.241 diff -u -r1.241 reader.c --- src/reader.c 22 Dec 2005 11:40:05 -0000 1.241 +++ src/reader.c 27 Dec 2005 17:37:28 -0000 @@ -36,6 +36,9 @@ #include "symlist.h" #include "symtab.h" +static void grammar_midrule_action (void); +static void grammar_symbol_append (symbol *sym, location loc); + static symbol_list *grammar = NULL; static bool start_flag = false; merger_list *merge_functions; @@ -153,7 +156,7 @@ 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); @@ -164,6 +167,11 @@ grammar = p; grammar_end = p; + + /* SYM = 0 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. @@ -178,7 +186,7 @@ `----------------------------------------------*/ void -grammar_rule_begin (symbol *lhs, location loc) +grammar_current_rule_begin (symbol *lhs, location loc) { if (!start_flag) { @@ -189,8 +197,6 @@ /* Start a new rule and record its lhs. */ ++nrules; - ++nritems; - previous_rule_end = grammar_end; grammar_symbol_append (lhs, loc); current_rule = grammar_end; @@ -207,17 +213,14 @@ } -/*------------------------------------------------------------------. -| 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; - /* Type check. If there is an action, then there is nothing we can do: the user @@ -225,36 +228,40 @@ Don't worry about the default action if $$ is untyped, since $$'s value can't be used. */ - if (!current_rule->action && lhs_type) + if (!r->action && r->sym->type_name) { - symbol *first_rhs = current_rule->next->sym; + symbol *first_rhs = r->next->sym; /* If $$ 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 (current_rule->location, + warn_at (r->location, _("type clash on default action: <%s> != <%s>"), lhs_type, rhs_type); } /* Warn if there is no default for $$ but we need one. */ else - warn_at (current_rule->location, + warn_at (r->location, _("empty rule for typed nonterminal, and no action")); } - - /* Check that all the symbol values are used. */ - if (typed) - { - symbol_list *l = current_rule; - int n = 1; - for (l = current_rule->next; l && l->sym; l = l->next, ++n) - /* The default action `uses' $1. */ - if (! (!current_rule->action && n == 1) - && l->sym->type_name && !l->used) - warn_at (current_rule->location, _("unused value: $%d"), n); - } + + /* Check that typed symbol values are used. */ + { + symbol_list *l = r; + int n = 0; + for (; l && l->sym; l = l->next, ++n) + if (! (l->used + || !l->sym->type_name + /* The default action, $$ = $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: $$")); + } } @@ -263,12 +270,12 @@ `-------------------------------------*/ 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); } @@ -279,7 +286,7 @@ | rule. | `-------------------------------------------------------------------*/ -void +static void grammar_midrule_action (void) { /* Since the action was written out with this rule's number, we must @@ -364,7 +371,6 @@ { if (current_rule->action) grammar_midrule_action (); - ++nritems; grammar_symbol_append (sym, loc); } Index: src/reader.h =================================================================== RCS file: /cvsroot/bison/bison/src/reader.h,v retrieving revision 1.46 diff -u -r1.46 reader.h --- src/reader.h 22 Dec 2005 11:40:05 -0000 1.46 +++ src/reader.h 27 Dec 2005 17:37:28 -0000 @@ -61,14 +61,11 @@ /* From reader.c. */ void grammar_start_symbol_set (symbol *sym, location loc); void prologue_augment (const char *prologue, location loc); -void grammar_symbol_append (symbol *sym, location loc); -void grammar_rule_begin (symbol *lhs, location loc); -void grammar_rule_end (location loc); -void grammar_midrule_action (void); +void grammar_current_rule_begin (symbol *lhs, location loc); +void grammar_current_rule_end (location loc); void grammar_current_rule_prec_set (symbol *precsym, location loc); void grammar_current_rule_dprec_set (int dprec, location loc); void grammar_current_rule_merge_set (uniqstr name, location loc); - void grammar_current_rule_symbol_append (symbol *sym, location loc); void grammar_current_rule_action_append (const char *action, location loc); extern symbol_list *current_rule; Index: src/scan-gram.l =================================================================== RCS file: /cvsroot/bison/bison/src/scan-gram.l,v retrieving revision 1.79 diff -u -r1.79 scan-gram.l --- src/scan-gram.l 22 Dec 2005 11:40:05 -0000 1.79 +++ src/scan-gram.l 27 Dec 2005 17:37:30 -0000 @@ -815,6 +815,7 @@ type_name = ""; obstack_fgrow1 (&obstack_for_string, "]b4_lhs_value([%s])[", type_name); + current_rule->used = true; } else { @@ -837,8 +838,7 @@ obstack_fgrow3 (&obstack_for_string, "]b4_rhs_value(%d, %d, [%s])[", rule_length, n, type_name); - if (typed) - symbol_list_n_used_set (current_rule, n, true); + symbol_list_n_used_set (current_rule, n, true); } else complain_at (loc, _("integer out of range: %s"), quote (text)); Index: tests/actions.at =================================================================== RCS file: /cvsroot/bison/bison/tests/actions.at,v retrieving revision 1.55 diff -u -r1.55 actions.at --- tests/actions.at 22 Dec 2005 11:40:05 -0000 1.55 +++ tests/actions.at 27 Dec 2005 17:37:33 -0000 @@ -30,13 +30,13 @@ # action. AT_DATA_GRAMMAR([[input.y]], -[[%{ +[[%error-verbose +%debug +%{ # include # include static void yyerror (const char *msg); static int yylex (void); -# define YYDEBUG 1 -# define YYERROR_VERBOSE 1 %} %% exp: { putchar ('0'); } @@ -91,13 +91,13 @@ AT_SETUP([Exotic Dollars]) AT_DATA_GRAMMAR([[input.y]], -[[%{ +[[%error-verbose +%debug +%{ # include # include static void yyerror (const char *msg); static int yylex (void); -# define YYDEBUG 1 -# define YYERROR_VERBOSE 1 # define USE(Var) %} @@ -107,13 +107,12 @@ }; %type a_1 a_2 a_5 - sum_of_the_five_previous_values + exp sum_of_the_five_previous_values %% exp: a_1 a_2 { $$ = 3; } { $$ = $3 + 1; } a_5 sum_of_the_five_previous_values { - USE (($1, $2, $5)); printf ("%d\n", $6); } ; @@ -147,7 +146,11 @@ } ]]) -AT_CHECK([bison -d -v -o input.c input.y]) +AT_CHECK([bison -d -v -o input.c input.y], 0, [], +[input.y:30.6-34.5: warning: unused value: $1 +input.y:30.6-34.5: warning: unused value: $2 +input.y:30.6-34.5: warning: unused value: $5 +]) AT_COMPILE([input]) AT_PARSER_CHECK([./input], 0, [[15 Index: tests/calc.at =================================================================== RCS file: /cvsroot/bison/bison/tests/calc.at,v retrieving revision 1.84 diff -u -r1.84 calc.at --- tests/calc.at 22 Dec 2005 11:40:05 -0000 1.84 +++ tests/calc.at 27 Dec 2005 17:37:34 -0000 @@ -129,15 +129,15 @@ | exp '^' exp { $$ = power ($1, $3); } | '(' exp ')' { $$ = $2; } | '(' error ')' { $$ = 1111; } -| '!' { YYERROR; } -| '-' error { YYERROR; } +| '!' { $$ = 0; YYERROR; } +| '-' error { $$ = 0; YYERROR; } ; %% -/* The input. */ +/* The input. */ static FILE *input; ]AT_LALR1_CC_IF( -[/* A C++ error reporting function. */ +[/* A C++ error reporting function. */ void yy::parser::error (const location& l, const std::string& m) { Index: tests/torture.at =================================================================== RCS file: /cvsroot/bison/bison/tests/torture.at,v retrieving revision 1.30 diff -u -r1.30 torture.at --- tests/torture.at 21 Sep 2005 20:08:38 -0000 1.30 +++ tests/torture.at 27 Dec 2005 17:37:35 -0000 @@ -50,13 +50,12 @@ print < #include -#define YYERROR_VERBOSE 1 -#define YYDEBUG 1 - static int yylex (void); static void yyerror (const char *msg); %} @@ -166,24 +165,25 @@ print < #include -#define YYERROR_VERBOSE 1 -#define YYDEBUG 1 - static int yylex (void); static void yyerror (const char *msg); %} -EOF +%token +EOF for my $size (1 .. $max) { - print "%token t$size $size \"$size\"\n"; + print " t$size $size \"$size\"\n"; }; print < -#include - -#define YYERROR_VERBOSE 1 -#define YYDEBUG 1 +# include +# include +# include static int yylex (void); static void yyerror (const char *msg); @@ -295,25 +295,26 @@ map { "n$_" } (1 .. $max)), "\n"; +print "%token\n"; for my $count (1 .. $max) { - print "%token t$count $count \"$count\"\n"; + print " t$count $count \"$count\"\n"; }; print <