Yacc - discriptionwhat is yacc ..gnu project

7/27/2019 Yacc - discriptionwhat is yacc ..gnu project

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yacc-*- C -*-

# Yacc compatible skeleton for Bison

# Copyright (C) 1984, 1989-1990, 2000-2012 Free Software Foundation,# Inc.

# This program is free software: you can redistribute it and/or modify# it under the terms of the GNU General Public License as published by# the Free Software Foundation, either version 3 of the License, or# (at your option) any later version.## This program is distributed in the hope that it will be useful,# but WITHOUT ANY WARRANTY; without even the implied warranty of# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the# GNU General Public License for more details.## You should have received a copy of the GNU General Public License# along with this program. If not, see .

# Check the value of %define api.push-pull.b4_percent_define_default([[api.push-pull]], [[pull]])

b4_percent_define_check_values([[[[api.push-pull]],[[pull]], [[push]], [[both]]]])

b4_define_flag_if([pull]) m4_define([b4_pull_flag], [[1]])b4_define_flag_if([push]) m4_define([b4_push_flag], [[1]])m4_case(b4_percent_define_get([[api.push-pull]]),

[pull], [m4_define([b4_push_flag], [[0]])],[push], [m4_define([b4_pull_flag], [[0]])])

# Handle BISON_USE_PUSH_FOR_PULL for the test suite. So that push parsing# tests function as written, do not let BISON_USE_PUSH_FOR_PULL modify the# behavior of Bison at all when push parsing is already requested.b4_define_flag_if([use_push_for_pull])b4_use_push_for_pull_if([

b4_push_if([m4_define([b4_use_push_for_pull_flag], [[0]])],[m4_define([b4_push_flag], [[1]])])])

# Check the value of %define parse.lac and friends, where LAC stands for# lookahead correction.b4_percent_define_default([[parse.lac]], [[none]])b4_percent_define_default([[parse.lac.es-capacity-initial]], [[20]])b4_percent_define_default([[parse.lac.memory-trace]], [[failures]])b4_percent_define_check_values([[[[parse.lac]], [[full]], [[none]]]],

[[[[parse.lac.memory-trace]],[[failures]], [[full]]]])

b4_define_flag_if([lac])m4_define([b4_lac_flag],

[m4_if(b4_percent_define_get([[parse.lac]]),[none], [[0]], [[1]])])

m4_include(b4_pkgdatadir/[c.m4])

## ---------------- #### Default values. #### ---------------- ##

# Stack parameters.m4_define_default([b4_stack_depth_max], [10000])m4_define_default([b4_stack_depth_init], [200])

## ------------------------ ##Page 1


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yacc## Pure/impure interfaces. #### ------------------------ ##

b4_percent_define_default([[api.pure]], [[false]])b4_percent_define_check_values([[[[api.pure]],

[[false]], [[true]], [[]], [[full]]]])

m4_define([b4_pure_flag], [[0]])m4_case(b4_percent_define_get([[api.pure]]),

[false], [m4_define([b4_pure_flag], [[0]])],[true], [m4_define([b4_pure_flag], [[1]])],[], [m4_define([b4_pure_flag], [[1]])],[full], [m4_define([b4_pure_flag], [[2]])])

m4_define([b4_pure_if],[m4_case(b4_pure_flag,

[0], [$2],[1], [$1],[2], [$1])])[m4_fatal([invalid api.pure value: ]$1)])])

# b4_yyerror_arg_loc_if(ARG)

# --------------------------# Expand ARG iff yyerror is to be given a location as argument.m4_define([b4_yyerror_arg_loc_if],[b4_locations_if([m4_case(b4_pure_flag,

[1], [m4_ifset([b4_parse_param], [$1])],[2], [$1])])])

# b4_yyerror_args# ---------------# Arguments passed to yyerror: user args plus yylloc.m4_define([b4_yyerror_args],[b4_yyerror_arg_loc_if([&yylloc, ])dnlm4_ifset([b4_parse_param], [b4_c_args(b4_parse_param), ])])

# b4_lex_param# ------------# Accumulate in b4_lex_param all the yylex arguments.# b4_lex_param arrives quoted twice, but we want to keep only one level.m4_define([b4_lex_param],m4_dquote(b4_pure_if([[[[YYSTYPE *]], [[&yylval]]][]dnlb4_locations_if([, [[YYLTYPE *], [&yylloc]]])m4_ifdef([b4_lex_param], [, ])])dnlm4_ifdef([b4_lex_param], b4_lex_param)))

## ------------ #### Data Types. #### ------------ ##

# b4_int_type(MIN, MAX)# ---------------------# Return the smallest int type able to handle numbers ranging from# MIN to MAX (included). Overwrite the version from c.m4, which# uses only C89 types, so that the user can override the shorter# types, and so that pre-C89 compilers are handled correctly.m4_define([b4_int_type],[m4_if(b4_ints_in($@, [0], [255]), [1], [yytype_uint8],

b4_ints_in($@, [-128], [127]), [1], [yytype_int8],

b4_ints_in($@, [0], [65535]), [1], [yytype_uint16],b4_ints_in($@, [-32768], [32767]), [1], [yytype_int16],

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yacc

m4_eval([0


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yacc_Pragma ("GCC diagnostic ignored \"-Wuninitialized\"")\_Pragma ("GCC diagnostic ignored \"-Wmaybe-uninitialized\"")

# define YY_IGNORE_MAYBE_UNINITIALIZED_END \_Pragma ("GCC diagnostic pop")

#else/* Default value used for initialization, for pacifying older GCCs

or non-GCC compilers. */static YYSTYPE yyval_default;# define YY_INITIAL_VALUE(Value) = Value#endif]b4_locations_if([[static YYLTYPE yyloc_default][]b4_yyloc_default[;]])])[#ifndef YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN# define YY_IGNORE_MAYBE_UNINITIALIZED_BEGIN# define YY_IGNORE_MAYBE_UNINITIALIZED_END#endif#ifndef YY_INITIAL_VALUE# define YY_INITIAL_VALUE(Value) /* Nothing. */#endif

/* The semantic value of the lookahead symbol. */YYSTYPE yylval YY_INITIAL_VALUE(yyval_default);]b4_locations_if([[

/* Location data for the lookahead symbol. */YYLTYPE yylloc]b4_pure_if([ = yyloc_default], [b4_yyloc_default])[;]])b4_pure_if([], [[

/* Number of syntax errors so far. */int yynerrs;]])])

# b4_declare_parser_state_variables# ---------------------------------# Declare all the variables that are needed to maintain the parser state# between calls to yypush_parse.m4_define([b4_declare_parser_state_variables], [b4_pure_if([[

/* Number of syntax errors so far. */int yynerrs;

]])[int yystate;/* Number of tokens to shift before error messages enabled. */int yyerrstatus;

/* The stacks and their tools:`yyss': related to states.`yyvs': related to semantic values.]b4_locations_if([[`yyls': related to locations.]])[

Refer to the stacks through separate pointers, to allow yyoverflowto reallocate them elsewhere. */

/* The state stack. */yytype_int16 yyssa[YYINITDEPTH];yytype_int16 *yyss;yytype_int16 *yyssp;

/* The semantic value stack. */YYSTYPE yyvsa[YYINITDEPTH];YYSTYPE *yyvs;YYSTYPE *yyvsp;]b4_locations_if([[

/* The location stack. */YYLTYPE yylsa[YYINITDEPTH];YYLTYPE *yyls;

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yaccYYLTYPE *yylsp;

/* The locations where the error started and ended. */YYLTYPE yyerror_range[3];]])[

YYSIZE_T yystacksize;]b4_lac_if([[

yytype_int16yyesa@{]b4_percent_define_get([[parse.lac.es-capacity-initial]])[@};

yytype_int16 *yyes;YYSIZE_T yyes_capacity;]])])

# b4_declare_yyparse_push_# ------------------------# Declaration of yyparse (and dependencies) when using the push parser# (including in pull mode).m4_define([b4_declare_yyparse_push_],[[#ifndef YYPUSH_MORE_DEFINED# define YYPUSH_MORE_DEFINEDenum { YYPUSH_MORE = 4 };#endif

typedef struct ]b4_prefix[pstate ]b4_prefix[pstate;

]b4_pull_if([b4_c_function_decl([b4_prefix[parse]], [[int]], b4_parse_param)])b4_c_function_decl([b4_prefix[push_parse]], [[int]],

[[b4_prefix[pstate *ps]], [[ps]]]b4_pure_if([,[[[int pushed_char]], [[pushed_char]]],[[b4_api_PREFIX[STYPE const *pushed_val]], [[pushed_val]]]b4_locations_if([,[[b4_api_PREFIX[LTYPE *pushed_loc]], [[pushed_loc]]]])])m4_ifset([b4_parse_param],

[,b4_parse_param]))

b4_pull_if([b4_c_function_decl([b4_prefix[pull_parse]], [[int]],[[b4_prefix[pstate *ps]], [[ps]]]m4_ifset([b4_parse_param], [,b4_parse_param]))])

b4_c_function_decl([b4_prefix[pstate_new]], [b4_prefix[pstate *]],

[[[void]], []])b4_c_function_decl([b4_prefix[pstate_delete]], [[void]],[[b4_prefix[pstate *ps]], [[ps]]])dnl

])

# b4_declare_yyparse_# -------------------# When not the push parser.m4_define([b4_declare_yyparse_],[[#ifdef YYPARSE_PARAM]b4_c_function_decl(b4_prefix[parse], [int],

[[void *YYPARSE_PARAM], [YYPARSE_PARAM]])[#else /* ! YYPARSE_PARAM */]b4_c_function_decl(b4_prefix[parse], [int], b4_parse_param)[#endif /* ! YYPARSE_PARAM */]dnl])

# b4_declare_yyparse# ------------------m4_define([b4_declare_yyparse],[b4_push_if([b4_declare_yyparse_push_],

[b4_declare_yyparse_])[]dnl])

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yacc# b4_shared_declarations# ----------------------# Declaration that might either go into the header (if --defines)# or open coded in the parser body.m4_define([b4_shared_declarations],[b4_cpp_guard_open([b4_spec_defines_file])[]b4_declare_yydebug[]b4_percent_code_get([[requires]])[]b4_token_enums_defines(b4_tokens)[]b4_declare_yylstype[]b4_declare_yyparse[]b4_percent_code_get([[provides]])[]b4_cpp_guard_close([b4_spec_defines_file])[]dnl])

## -------------- #### Output files. #### -------------- ##

b4_output_begin([b4_parser_file_name])b4_copyright([Bison implementation for Yacc-like parsers in C],

[1984, 1989-1990, 2000-2012])[

/* C LALR(1) parser skeleton written by Richard Stallman, bysimplifying the original so-called "semantic" parser. */

/* All symbols defined below should begin with yy or YY, to avoidinfringing on user name space. This should be done even for localvariables, as they might otherwise be expanded by user macros.There are some unavoidable exceptions within include files todefine necessary library symbols; they are noted "INFRINGES ONUSER NAME SPACE" below. */

]b4_identificationb4_percent_code_get([[top]])[]dnlm4_if(b4_api_prefix, [yy], [],

[[/* Substitute the type names. */#define YYSTYPE ]b4_api_PREFIX[STYPE]b4_locations_if([[#define YYLTYPE ]b4_api_PREFIX[LTYPE]])])[]m4_if(b4_prefix, [yy], [],[[/* Substitute the variable and function names. */]b4_pull_if([[#define yyparse ]b4_prefix[parse]])b4_push_if([[#define yypush_parse ]b4_prefix[push_parse]b4_pull_if([[#define yypull_parse ]b4_prefix[pull_parse]])[#define yypstate_new ]b4_prefix[pstate_new#define yypstate_delete ]b4_prefix[pstate_delete#define yypstate ]b4_prefix[pstate]])[#define yylex ]b4_prefix[lex#define yyerror ]b4_prefix[error#define yylval ]b4_prefix[lval#define yychar ]b4_prefix[char#define yydebug ]b4_prefix[debug#define yynerrs ]b4_prefix[nerrs]b4_locations_if([[#define yylloc ]b4_prefix[lloc]])])[

/* Copy the first part of user declarations. */]b4_user_pre_prologue[

]b4_null_define[

/* Enabling verbose error messages. */#ifdef YYERROR_VERBOSE

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yacc# undef YYERROR_VERBOSE# define YYERROR_VERBOSE 1#else# define YYERROR_VERBOSE ]b4_error_verbose_flag[#endif

]m4_ifval(m4_quote(b4_spec_defines_file),[[/* In a future release of Bison, this section will be replaced

by #include "@basename(]b4_spec_defines_file[@)". */]])dnlb4_shared_declarations[

/* Copy the second part of user declarations. */]b4_user_post_prologueb4_percent_code_get[]dnl

[#ifdef short# undef short#endif

#ifdef YYTYPE_UINT8typedef YYTYPE_UINT8 yytype_uint8;

#elsetypedef unsigned char yytype_uint8;#endif

#ifdef YYTYPE_INT8typedef YYTYPE_INT8 yytype_int8;#elif ]b4_c_modern[typedef signed char yytype_int8;#elsetypedef short int yytype_int8;#endif

#ifdef YYTYPE_UINT16typedef YYTYPE_UINT16 yytype_uint16;#else

typedef unsigned short int yytype_uint16;#endif

#ifdef YYTYPE_INT16typedef YYTYPE_INT16 yytype_int16;#elsetypedef short int yytype_int16;#endif

#ifndef YYSIZE_T# ifdef __SIZE_TYPE__# define YYSIZE_T __SIZE_TYPE__# elif defined size_t# define YYSIZE_T size_t# elif ! defined YYSIZE_T && ]b4_c_modern[# include /* INFRINGES ON USER NAME SPACE */# define YYSIZE_T size_t# else# define YYSIZE_T unsigned int# endif#endif

#define YYSIZE_MAXIMUM ((YYSIZE_T) -1)

#ifndef YY_# if defined YYENABLE_NLS && YYENABLE_NLS

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yacc# if ENABLE_NLS# include /* INFRINGES ON USER NAME SPACE */# define YY_(Msgid) dgettext ("bison-runtime", Msgid)# endif# endif# ifndef YY_# define YY_(Msgid) Msgid# endif#endif

/* Suppress unused-variable warnings by "using" E. */#if ! defined lint || defined __GNUC__# define YYUSE(E) ((void) (E))#else# define YYUSE(E) /* empty */#endif

/* Identity function, used to suppress warnings about constant conditions. */#ifndef lint# define YYID(N) (N)#else]b4_c_function_def([YYID], [static int], [[int yyi], [yyi]])[

{return yyi;

}#endif

#if ]b4_lac_if([[1]], [[! defined yyoverflow || YYERROR_VERBOSE]])[

/* The parser invokes alloca or malloc; define the necessary symbols. */]dnlb4_push_if([], [b4_lac_if([], [[

# ifdef YYSTACK_USE_ALLOCA# if YYSTACK_USE_ALLOCA# ifdef __GNUC__# define YYSTACK_ALLOC __builtin_alloca# elif defined __BUILTIN_VA_ARG_INCR

# include /* INFRINGES ON USER NAME SPACE */# elif defined _AIX# define YYSTACK_ALLOC __alloca# elif defined _MSC_VER# include /* INFRINGES ON USER NAME SPACE */# define alloca _alloca# else# define YYSTACK_ALLOC alloca# if ! defined _ALLOCA_H && ! defined EXIT_SUCCESS && ]b4_c_modern[# include /* INFRINGES ON USER NAME SPACE */

/* Use EXIT_SUCCESS as a witness for stdlib.h. */# ifndef EXIT_SUCCESS# define EXIT_SUCCESS 0# endif# endif# endif# endif# endif]])])[

# ifdef YYSTACK_ALLOC/* Pacify GCC's `empty if-body' warning. */

# define YYSTACK_FREE(Ptr) do { /* empty */; } while (YYID (0))# ifndef YYSTACK_ALLOC_MAXIMUM

/* The OS might guarantee only one guard page at the bottom of the stack,and a page size can be as small as 4096 bytes. So we cannot safelyinvoke alloca (N) if N exceeds 4096. Use a slightly smaller number

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yaccto allow for a few compiler-allocated temporary stack slots. */

# define YYSTACK_ALLOC_MAXIMUM 4032 /* reasonable circa 2006 */# endif# else# define YYSTACK_ALLOC YYMALLOC# define YYSTACK_FREE YYFREE# ifndef YYSTACK_ALLOC_MAXIMUM# define YYSTACK_ALLOC_MAXIMUM YYSIZE_MAXIMUM# endif# if (defined __cplusplus && ! defined EXIT_SUCCESS \

&& ! ((defined YYMALLOC || defined malloc) \ && (defined YYFREE || defined free)))# include /* INFRINGES ON USER NAME SPACE */# ifndef EXIT_SUCCESS# define EXIT_SUCCESS 0# endif# endif# ifndef YYMALLOC# define YYMALLOC malloc# if ! defined malloc && ! defined EXIT_SUCCESS && ]b4_c_modern[void *malloc (YYSIZE_T); /* INFRINGES ON USER NAME SPACE */# endif

# endif# ifndef YYFREE# define YYFREE free# if ! defined free && ! defined EXIT_SUCCESS && ]b4_c_modern[void free (void *); /* INFRINGES ON USER NAME SPACE */# endif# endif# endif]b4_lac_if([[# define YYCOPY_NEEDED 1]])[#endif]b4_lac_if([], [[ /* ! defined yyoverflow || YYERROR_VERBOSE */]])[

#if (! defined yyoverflow \&& (! defined __cplusplus \ || (]b4_locations_if([[defined ]b4_api_PREFIX[LTYPE_IS_TRIVIAL &&

]b4_api_PREFIX[LTYPE_IS_TRIVIAL \ && ]])[defined ]b4_api_PREFIX[STYPE_IS_TRIVIAL &&]b4_api_PREFIX[STYPE_IS_TRIVIAL)))

/* A type that is properly aligned for any stack member. */union yyalloc{

yytype_int16 yyss_alloc;YYSTYPE yyvs_alloc;]b4_locations_if([YYLTYPE yyls_alloc;])[

};

/* The size of the maximum gap between one aligned stack and the next. */# define YYSTACK_GAP_MAXIMUM (sizeof (union yyalloc) - 1)

/* The size of an array large to enough to hold all stacks, each withN elements. */

]b4_locations_if([# define YYSTACK_BYTES(N) \

((N) * (sizeof (yytype_int16) + sizeof (YYSTYPE) + sizeof (YYLTYPE)) \+ 2 * YYSTACK_GAP_MAXIMUM)],

[# define YYSTACK_BYTES(N) \((N) * (sizeof (yytype_int16) + sizeof (YYSTYPE)) \+ YYSTACK_GAP_MAXIMUM)])[

# define YYCOPY_NEEDED 1Page 9


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yacc

/* Relocate STACK from its old location to the new one. Thelocal variables YYSIZE and YYSTACKSIZE give the old and new number ofelements in the stack, and YYPTR gives the new location of thestack. Advance YYPTR to a properly aligned location for the nextstack. */ # define YYSTACK_RELOCATE(Stack_alloc, Stack) \

do \ { \ YYSIZE_T yynewbytes; \ YYCOPY (&yyptr->Stack_alloc, Stack, yysize); \ Stack = &yyptr->Stack_alloc; \ yynewbytes = yystacksize * sizeof (*Stack) + YYSTACK_GAP_MAXIMUM; \ yyptr += yynewbytes / sizeof (*yyptr); \ } \while (YYID (0))

#endif

#if defined YYCOPY_NEEDED && YYCOPY_NEEDED/* Copy COUNT objects from SRC to DST. The source and destination do

not overlap. */

# ifndef YYCOPY# if defined __GNUC__ && 1 < __GNUC__# define YYCOPY(Dst, Src, Count) \

__builtin_memcpy (Dst, Src, (Count) * sizeof (*(Src)))# else# define YYCOPY(Dst, Src, Count) \

do \{ \YYSIZE_T yyi; \for (yyi = 0; yyi < (Count); yyi++) \

(Dst)[yyi] = (Src)[yyi]; \} \

while (YYID (0))# endif# endif

#endif /* !YYCOPY_NEEDED *//* YYFINAL -- State number of the termination state. */#define YYFINAL ]b4_final_state_number[/* YYLAST -- Last index in YYTABLE. */#define YYLAST ]b4_last[

/* YYNTOKENS -- Number of terminals. */#define YYNTOKENS ]b4_tokens_number[/* YYNNTS -- Number of nonterminals. */#define YYNNTS ]b4_nterms_number[/* YYNRULES -- Number of rules. */#define YYNRULES ]b4_rules_number[/* YYNRULES -- Number of states. */#define YYNSTATES ]b4_states_number[

/* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */#define YYUNDEFTOK ]b4_undef_token_number[#define YYMAXUTOK ]b4_user_token_number_max[

#define YYTRANSLATE(YYX) \((unsigned int) (YYX)


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yacc]b4_translate[

};

#if ]b4_api_PREFIX[DEBUG/* YYPRHS[YYN] -- Index of the first RHS symbol of rule number YYN in

YYRHS. */static const ]b4_int_type_for([b4_prhs])[ yyprhs[] ={

]b4_prhs[};

/* YYRHS -- A `-1'-separated list of the rules' RHS. */static const ]b4_int_type_for([b4_rhs])[ yyrhs[] ={

]b4_rhs[};

/* YYRLINE[YYN] -- source line where rule number YYN was defined. */static const ]b4_int_type_for([b4_rline])[ yyrline[] ={

]b4_rline[};

#endif

#if ]b4_api_PREFIX[DEBUG || YYERROR_VERBOSE || ]b4_token_table_flag[/* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.

First, the terminals, then, starting at YYNTOKENS, nonterminals. */static const char *const yytname[] ={

]b4_tname[};#endif

# ifdef YYPRINT/* YYTOKNUM[YYLEX-NUM] -- Internal token number corresponding to

token YYLEX-NUM. */static const ]b4_int_type_for([b4_toknum])[ yytoknum[] =

{ ]b4_toknum[};# endif

/* YYR1[YYN] -- Symbol number of symbol that rule YYN derives. */static const ]b4_int_type_for([b4_r1])[ yyr1[] ={

]b4_r1[};

/* YYR2[YYN] -- Number of symbols composing right hand side of rule YYN. */static const ]b4_int_type_for([b4_r2])[ yyr2[] ={

]b4_r2[};

/* YYDEFACT[STATE-NAME] -- Default reduction number in state STATE-NUM.Performed when YYTABLE doesn't specify something else to do. Zeromeans the default is an error. */

static const ]b4_int_type_for([b4_defact])[ yydefact[] ={

]b4_defact[};

/* YYDEFGOTO[NTERM-NUM]. */Page 11


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yaccstatic const ]b4_int_type_for([b4_defgoto])[ yydefgoto[] ={

]b4_defgoto[};

/* YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describingSTATE-NUM. */

#define YYPACT_NINF ]b4_pact_ninf[static const ]b4_int_type_for([b4_pact])[ yypact[] ={

]b4_pact[};

/* YYPGOTO[NTERM-NUM]. */static const ]b4_int_type_for([b4_pgoto])[ yypgoto[] ={

]b4_pgoto[};

/* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. Ifpositive, shift that token. If negative, reduce the rule whichnumber is the opposite. If YYTABLE_NINF, syntax error. */

#define YYTABLE_NINF ]b4_table_ninf[static const ]b4_int_type_for([b4_table])[ yytable[] ={

]b4_table[};

#define yypact_value_is_default(Yystate) \]b4_table_value_equals([[pact]], [[Yystate]], [b4_pact_ninf])[

#define yytable_value_is_error(Yytable_value) \]b4_table_value_equals([[table]], [[Yytable_value]], [b4_table_ninf])[

static const ]b4_int_type_for([b4_check])[ yycheck[] ={

]b4_check[

};/* YYSTOS[STATE-NUM] -- The (internal number of the) accessing

symbol of state STATE-NUM. */static const ]b4_int_type_for([b4_stos])[ yystos[] ={

]b4_stos[};

#define yyerrok (yyerrstatus = 0)#define yyclearin (yychar = YYEMPTY) #define YYEMPTY (-2) #define YYEOF 0#define YYACCEPT goto yyacceptlab #define YYABORT goto yyabortlab

#define YYERROR goto yyerrorlab/* Like YYERROR except do call yyerror. This remains here temporarily

to ease the transition to the new meaning of YYERROR, for GCC.Once GCC version 2 has supplanted version 1, this can go. However,YYFAIL appears to be in use. Nevertheless, it is formally deprecatedin Bison 2.4.2's NEWS entry, where a plan to phase it out isdiscussed. */

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yacc #define YYFAIL goto yyerrlab#if defined YYFAIL

/* This is here to suppress warnings from the GCC cpp's-Wunused-macros. Normally we don't worry about that warning, butsome users do, and we want to make it easy for users to removeYYFAIL uses, which will produce warnings from Bison 2.5. */

#endif

#define YYRECOVERING() (!!yyerrstatus)

#define YYBACKUP(Token, Value) \do \

if (yychar == YYEMPTY) \{ \yychar = (Token); \yylval = (Value); \YYPOPSTACK (yylen); \yystate = *yyssp; \]b4_lac_if([[YY_LAC_DISCARD ("YYBACKUP"); \]])[goto yybackup; \

} \else \

{ \yyerror (]b4_yyerror_args[YY_("syntax error: cannot back up")); \ YYERROR; \ } \

while (YYID (0))

/* Error token number */#define YYTERROR 1#define YYERRCODE 256]b4_locations_if([[]b4_yylloc_default_define[#define YYRHSLOC(Rhs, K) ((Rhs)[K])]])[]b4_yy_location_print_define[

/* YYLEX -- calling `yylex' with the right arguments. */#ifdef YYLEX_PARAM# define YYLEX yylex (]b4_pure_if([&yylval[]b4_locations_if([, &yylloc]),])[YYLEX_PARAM)#else# define YYLEX ]b4_c_function_call([yylex], [int], b4_lex_param)[#endif

/* Enable debugging if requested. */#if ]b4_api_PREFIX[DEBUG

# ifndef YYFPRINTF# include /* INFRINGES ON USER NAME SPACE */# define YYFPRINTF fprintf# endif

# define YYDPRINTF(Args) \ do { \ if (yydebug) \ YYFPRINTF Args; \} while (YYID (0))

# define YY_SYMBOL_PRINT(Title, Type, Value, Location) \ do { \ if (yydebug) \Page 13


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yacc { \ YYFPRINTF (stderr, "%s ", Title); \ yy_symbol_print (stderr, \ Type, Value]b4_locations_if([, Location])[]b4_user_args[); \ YYFPRINTF (stderr, "\n"); \ } \} while (YYID (0))

]b4_yy_symbol_print_generate([b4_c_function_def])[

/*------------------------------------------------------------------.| yy_stack_print -- Print the state stack from its BOTTOM up to its || TOP (included). |`------------------------------------------------------------------*/

]b4_c_function_def([yy_stack_print], [static void], [[yytype_int16 *yybottom], [yybottom]], [[yytype_int16 *yytop], [yytop]])[{

YYFPRINTF (stderr, "Stack now");for (; yybottom


15/33

yacc do { \ if (yydebug) \yy_reduce_print (yyvsp, ]b4_locations_if([yylsp, ])[Rule]b4_user_args[); \

} while (YYID (0))

/* Nonzero means print parse trace. It is left uninitialized so thatmultiple parsers can coexist. */

int yydebug;#else /* !]b4_api_PREFIX[DEBUG */# define YYDPRINTF(Args)# define YY_SYMBOL_PRINT(Title, Type, Value, Location)# define YY_STACK_PRINT(Bottom, Top)# define YY_REDUCE_PRINT(Rule)#endif /* !]b4_api_PREFIX[DEBUG */

/* YYINITDEPTH -- initial size of the parser's stacks. */#ifndef YYINITDEPTH# define YYINITDEPTH ]b4_stack_depth_init[#endif

/* YYMAXDEPTH -- maximum size the stacks can grow to (effective only

if the built-in stack extension method is used).

Do not make this value too large; the results are undefined ifYYSTACK_ALLOC_MAXIMUM < YYSTACK_BYTES (YYMAXDEPTH)evaluated with infinite-precision integer arithmetic. */

#ifndef YYMAXDEPTH# define YYMAXDEPTH ]b4_stack_depth_max[#endif]b4_lac_if([[

/* Given a state stack such that *YYBOTTOM is its bottom, such that*YYTOP is either its top or is YYTOP_EMPTY to indicate an emptystack, and such that *YYCAPACITY is the maximum number of elements itcan hold without a reallocation, make sure there is enough room tostore YYADD more elements. If not, allocate a new stack using

YYSTACK_ALLOC, copy the existing elements, and adjust *YYBOTTOM,*YYTOP, and *YYCAPACITY to reflect the new capacity and memorylocation. If *YYBOTTOM != YYBOTTOM_NO_FREE, then free the old stackusing YYSTACK_FREE. Return 0 if successful or if no reallocation isrequired. Return 1 if memory is exhausted. */

static intyy_lac_stack_realloc (YYSIZE_T *yycapacity, YYSIZE_T yyadd,#if ]b4_api_PREFIX[DEBUG

char const *yydebug_prefix,char const *yydebug_suffix,

#endifyytype_int16 **yybottom,yytype_int16 *yybottom_no_free,yytype_int16 **yytop, yytype_int16 *yytop_empty)

{YYSIZE_T yysize_old =

*yytop == yytop_empty ? 0 : *yytop - *yybottom + 1;YYSIZE_T yysize_new = yysize_old + yyadd;if (*yycapacity < yysize_new)

{YYSIZE_T yyalloc = 2 * yysize_new;yytype_int16 *yybottom_new;/* Use YYMAXDEPTH for maximum stack size given that the stack

should never need to grow larger than the main state stackneeds to grow without LAC. */

if (YYMAXDEPTH < yysize_new)Page 15


16/33

yacc{YYDPRINTF ((stderr, "%smax size exceeded%s", yydebug_prefix,

yydebug_suffix));return 1;

}if (YYMAXDEPTH < yyalloc)

yyalloc = YYMAXDEPTH;yybottom_new =

(yytype_int16*) YYSTACK_ALLOC (yyalloc * sizeof *yybottom_new);if (!yybottom_new)

{YYDPRINTF ((stderr, "%srealloc failed%s", yydebug_prefix,

yydebug_suffix));return 1;

}if (*yytop != yytop_empty)

{YYCOPY (yybottom_new, *yybottom, yysize_old);*yytop = yybottom_new + (yysize_old - 1);

}if (*yybottom != yybottom_no_free)

YYSTACK_FREE (*yybottom);

*yybottom = yybottom_new;*yycapacity =

yyalloc;]m4_if(b4_percent_define_get([[parse.lac.memory-trace]]),[full], [[

YYDPRINTF ((stderr, "%srealloc to %lu%s", yydebug_prefix,(unsigned long int) yyalloc, yydebug_suffix));]])[

}return 0;

}

/* Establish the initial context for the current lookahead if no initialcontext is currently established.

We define a context as a snapshot of the parser stacks. We definethe initial context for a lookahead as the context in which the

parser initially examines that lookahead in order to select asyntactic action. Thus, if the lookahead eventually provessyntactically unacceptable (possibly in a later context reached via aseries of reductions), the initial context can be used to determinethe exact set of tokens that would be syntactically acceptable in thelookahead's place. Moreover, it is the context after which anyfurther semantic actions would be erroneous because they would bedetermined by a syntactically unacceptable token.

YY_LAC_ESTABLISH should be invoked when a reduction is about to beperformed in an inconsistent state (which, for the purposes of LAC,includes consistent states that don't know they're consistent becausetheir default reductions have been disabled). Iff there is alookahead token, it should also be invoked before reporting a syntaxerror. This latter case is for the sake of the debugging output.

For parse.lac=full, the implementation of YY_LAC_ESTABLISH is asfollows. If no initial context is currently established for thecurrent lookahead, then check if that lookahead can eventually beshifted if syntactic actions continue from the current context.Report a syntax error if it cannot. */

#define YY_LAC_ESTABLISH \do { \

if (!yy_lac_established) \{ \YYDPRINTF ((stderr, \

Page 16


17/33

yacc"LAC: initial context established for %s\n", \yytname[yytoken])); \

yy_lac_established = 1; \{ \

int yy_lac_status = \yy_lac (yyesa, &yyes, &yyes_capacity, yyssp, yytoken); \

if (yy_lac_status == 2) \goto yyexhaustedlab; \

if (yy_lac_status == 1) \goto yyerrlab; \

} \} \

} while (YYID (0))

/* Discard any previous initial lookahead context because of Event,which may be a lookahead change or an invalidation of the currentlyestablished initial context for the current lookahead.

The most common example of a lookahead change is a shift. An exampleof both cases is syntax error recovery. That is, a syntax erroroccurs when the lookahead is syntactically erroneous for thecurrently established initial context, so error recovery manipulates

the parser stacks to try to find a new initial context in which thecurrent lookahead is syntactically acceptable. If it fails to findsuch a context, it discards the lookahead. */

#if ]b4_api_PREFIX[DEBUG# define YY_LAC_DISCARD(Event) \do { \

if (yy_lac_established) \{ \if (yydebug) \

YYFPRINTF (stderr, "LAC: initial context discarded due to " \Event "\n"); \

yy_lac_established = 0; \} \

} while (YYID (0))#else

# define YY_LAC_DISCARD(Event) yy_lac_established = 0#endif

/* Given the stack whose top is *YYSSP, return 0 iff YYTOKEN caneventually (after perhaps some reductions) be shifted, return 1 ifnot, or return 2 if memory is exhausted. As preconditions andpostconditions: *YYES_CAPACITY is the allocated size of the array towhich *YYES points, and either *YYES = YYESA or *YYES points to anarray allocated with YYSTACK_ALLOC. yy_lac may overwrite thecontents of either array, alter *YYES and *YYES_CAPACITY, and freeany old *YYES other than YYESA. */

static intyy_lac (yytype_int16 *yyesa, yytype_int16 **yyes,

YYSIZE_T *yyes_capacity, yytype_int16 *yyssp, int yytoken){

yytype_int16 *yyes_prev = yyssp;yytype_int16 *yyesp = yyes_prev;YYDPRINTF ((stderr, "LAC: checking lookahead %s:", yytname[yytoken]));if (yytoken == YYUNDEFTOK)

{YYDPRINTF ((stderr, " Always Err\n"));return 1;

}while (1)

{int yyrule = yypact[*yyesp];

Page 17


18/33

yaccif (yypact_value_is_default (yyrule)

|| (yyrule += yytoken) < 0 || YYLAST < yyrule|| yycheck[yyrule] != yytoken)

{yyrule = yydefact[*yyesp];if (yyrule == 0)

{YYDPRINTF ((stderr, " Err\n"));return 1;

}}

else{yyrule = yytable[yyrule];if (yytable_value_is_error (yyrule))

{YYDPRINTF ((stderr, " Err\n"));return 1;

}if (0 < yyrule)

{YYDPRINTF ((stderr, " S%d\n", yyrule));

return 0;}

yyrule = -yyrule;}

{YYSIZE_T yylen = yyr2[yyrule];YYDPRINTF ((stderr, " R%d", yyrule - 1));if (yyesp != yyes_prev){

YYSIZE_T yysize = yyesp - *yyes + 1;if (yylen < yysize){

yyesp -= yylen;yylen = 0;

}

else{yylen -= yysize;yyesp = yyes_prev;

}}

if (yylen)yyesp = yyes_prev -= yylen;

}{

int yystate;{int yylhs = yyr1[yyrule] - YYNTOKENS;yystate = yypgoto[yylhs] + *yyesp;if (yystate < 0 || YYLAST < yystate

|| yycheck[yystate] != *yyesp)yystate = yydefgoto[yylhs];

elseyystate = yytable[yystate];

}if (yyesp == yyes_prev){

yyesp = *yyes;*yyesp = yystate;

}else

Page 18


19/33

yacc{

if (yy_lac_stack_realloc (yyes_capacity, 1,#if ]b4_api_PREFIX[DEBUG

" (", ")",#endif

yyes, yyesa, &yyesp, yyes_prev)){

YYDPRINTF ((stderr, "\n"));return 2;

}*++yyesp = yystate;

}YYDPRINTF ((stderr, " G%d", yystate));

}}

}]])[

#if YYERROR_VERBOSE

# ifndef yystrlen# if defined __GLIBC__ && defined _STRING_H

# define yystrlen strlen# else/* Return the length of YYSTR. */]b4_c_function_def([yystrlen], [static YYSIZE_T],

[[const char *yystr], [yystr]])[{

YYSIZE_T yylen;for (yylen = 0; yystr[yylen]; yylen++)

continue;return yylen;

}# endif# endif

# ifndef yystpcpy

# if defined __GLIBC__ && defined _STRING_H && defined _GNU_SOURCE# define yystpcpy stpcpy# else/* Copy YYSRC to YYDEST, returning the address of the terminating '\0' in

YYDEST. */]b4_c_function_def([yystpcpy], [static char *],

[[char *yydest], [yydest]], [[const char *yysrc], [yysrc]])[{

char *yyd = yydest;const char *yys = yysrc;

while ((*yyd++ = *yys++) != '\0')continue;

return yyd - 1;}# endif# endif

# ifndef yytnamerr/* Copy to YYRES the contents of YYSTR after stripping away unnecessary

quotes and backslashes, so that it's suitable for yyerror. Theheuristic is that double-quoting is unnecessary unless the stringcontains an apostrophe, a comma, or backslash (other thanbackslash-backslash). YYSTR is taken from yytname. If YYRES isnull, do not copy; instead, return the length of what the result

Page 19


20/33

yaccwould have been. */

static YYSIZE_Tyytnamerr (char *yyres, const char *yystr){

if (*yystr == '"'){YYSIZE_T yyn = 0;char const *yyp = yystr;

for (;;) switch (*++yyp) { case '\'': case ',': goto do_not_strip_quotes; case '\\': if (*++yyp != '\\') goto do_not_strip_quotes; /* Fall through. */ default: if (yyres) yyres[yyn] = *yyp; yyn++; break; case '"': if (yyres) yyres[yyn] = '\0'; return yyn; }

do_not_strip_quotes: ;}

if (! yyres)return yystrlen (yystr);

return yystpcpy (yyres, yystr) - yyres;}# endif

/* Copy into *YYMSG, which is of size *YYMSG_ALLOC, an error messageabout the unexpected token YYTOKEN for the state stack whose top isYYSSP.]b4_lac_if([[ In order to see if a particular token T is avalid looakhead, invoke yy_lac (YYESA, YYES, YYES_CAPACITY, YYSSP, T).]])[

Return 0 if *YYMSG was successfully written. Return 1 if *YYMSG isnot large enough to hold the message. In that case, also set*YYMSG_ALLOC to the required number of bytes. Return 2 if therequired number of bytes is too large to store]b4_lac_if([[ or ifyy_lac returned 2]])[. */

static intyysyntax_error (YYSIZE_T *yymsg_alloc, char **yymsg,

]b4_lac_if([[yytype_int16 *yyesa, yytype_int16 **yyes,YYSIZE_T *yyes_capacity, ]])[yytype_int16 *yyssp, int yytoken)

{YYSIZE_T yysize0 = yytnamerr (YY_NULL, yytname[yytoken]);YYSIZE_T yysize = yysize0;enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };/* Internationalized format string. */const char *yyformat = YY_NULL;/* Arguments of yyformat. */char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];

Page 20


21/33

yacc/* Number of reported tokens (one for the "unexpected", one per

"expected"). */int yycount = 0;

/* There are many possibilities here to consider:- Assume YYFAIL is not used. It's too flawed to consider. Seefor details. YYERROR is fine as it does not invoke thisfunction.

- If this state is a consistent state with a default action, thenthe only way this function was invoked is if the default actionis an error action. In that case, don't check for expectedtokens because there are none.

- The only way there can be no lookahead present (in yychar) is ifthis state is a consistent state with a default action. Thus,detecting the absence of a lookahead is sufficient to determinethat there is no unexpected or expected token to report. In thatcase, just report a simple "syntax error".

- Don't assume there isn't a lookahead just because this state is aconsistent state with a default action. There might have been aprevious inconsistent state, consistent state with a non-defaultaction, or user semantic action that manipulated yychar.]b4_lac_if([[

In the first two cases, it might appear that the current syntaxerror should have been detected in the previous state when yy_lacwas invoked. However, at that time, there might have been adifferent syntax error that discarded a different initial contextduring error recovery, leaving behind the current lookahead.]], [[

- Of course, the expected token list depends on states to havecorrect lookahead information, and it depends on the parser notto perform extra reductions after fetching a lookahead from thescanner and before detecting a syntax error. Thus, state merging(from LALR or IELR) and default reductions corrupt the expectedtoken list. However, the list is correct for canonical LR withone exception: it will still contain any token that will not beaccepted due to an error action in a later state.]])[

*/if (yytoken != YYEMPTY)

{ int yyn = yypact[*yyssp];]b4_lac_if([[YYDPRINTF ((stderr, "Constructing syntax error message\n"));]])[yyarg[yycount++] = yytname[yytoken];if (!yypact_value_is_default (yyn))

{]b4_lac_if([], [[/* Start YYX at -YYN if negative to avoid negative indexes in

YYCHECK. In other words, skip the first -YYN actions forthis state because they are default actions. */

int yyxbegin = yyn < 0 ? -yyn : 0;/* Stay within bounds of both yycheck and yytname. */int yychecklim = YYLAST - yyn + 1;int yyxend = yychecklim < YYNTOKENS ? yychecklim : YYNTOKENS;]])[int yyx;]b4_lac_if([[

for (yyx = 0; yyx < YYNTOKENS; ++yyx)if (yyx != YYTERROR && yyx != YYUNDEFTOK){

{int yy_lac_status = yy_lac (yyesa, yyes, yyes_capacity,

yyssp, yyx);if (yy_lac_status == 2)

return 2;if (yy_lac_status == 1)

continue;}]], [[

Page 21


22/33

yacc

for (yyx = yyxbegin; yyx < yyxend; ++yyx)if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR

&& !yytable_value_is_error (yytable[yyx + yyn])){]])[

if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM){

yycount = 1;yysize = yysize0;break;

}yyarg[yycount++] = yytname[yyx];{YYSIZE_T yysize1 = yysize + yytnamerr (YY_NULL, yytname[yyx]);if (! (yysize


23/33

yaccchar *yyp = *yymsg;int yyi = 0;while ((*yyp = *yyformat) != '\0')if (*yyp == '%' && yyformat[1] == 's' && yyi < yycount)

{yyp += yytnamerr (yyp, yyarg[yyi++]);yyformat += 2;

}else

{yyp++;yyformat++;

}}return 0;

}#endif /* YYERROR_VERBOSE */

]b4_yydestruct_generate([b4_c_function_def])[

]b4_pure_if([], [

b4_declare_scanner_communication_variables])[]b4_push_if([[

struct yypstate{]b4_declare_parser_state_variables[

/* Used to determine if this is the first time this instance hasbeen used. */

int yynew;};]b4_pure_if([], [[

static char yypstate_allocated = 0;]])b4_pull_if([

b4_c_function_def([[yyparse]], [[int]], b4_parse_param)[{

return yypull_parse (YY_NULL]m4_ifset([b4_parse_param],[[, ]b4_c_args(b4_parse_param)])[);

}]b4_c_function_def([[yypull_parse]], [[int]],

[[[yypstate *yyps]], [[yyps]]]m4_ifset([b4_parse_param], [,b4_parse_param]))[

{int yystatus;yypstate *yyps_local;]b4_pure_if([[int yychar;YYSTYPE yylval;]b4_locations_if([[static YYLTYPE yyloc_default][]b4_yyloc_default[;YYLTYPE yylloc = yyloc_default;]])])[if (yyps)

yyps_local = yyps;else

{yyps_local = yypstate_new ();if (!yyps_local)

{]b4_pure_if([[yyerror (]b4_yyerror_args[YY_("memory exhausted"));]], [[if (!yypstate_allocated)

yyerror (]b4_yyerror_args[YY_("memory exhausted"));]])[return 2;

}}

do {Page 23


24/33

yaccyychar = YYLEX;yystatus =yypush_parse (yyps_local]b4_pure_if([[, yychar, &yylval]b4_locations_if([[,

&yylloc]])])m4_ifset([b4_parse_param], [, b4_c_args(b4_parse_param)])[);} while (yystatus == YYPUSH_MORE);if (!yyps)

yypstate_delete (yyps_local);return yystatus;

}]])[

/* Initialize the parser data structure. */]b4_c_function_def([[yypstate_new]], [[yypstate *]])[{

yypstate *yyps;]b4_pure_if([], [[if (yypstate_allocated)

return YY_NULL;]])[yyps = (yypstate *) malloc (sizeof *yyps);if (!yyps)

return YY_NULL;yyps->yynew = 1;]b4_pure_if([], [[yypstate_allocated = 1;]])[return yyps;

}

]b4_c_function_def([[yypstate_delete]], [[void]],[[[yypstate *yyps]], [[yyps]]])[

{#ifndef yyoverflow

/* If the stack was reallocated but the parse did not complete, then thestack still needs to be freed. */

if (!yyps->yynew && yyps->yyss != yyps->yyssa)YYSTACK_FREE (yyps->yyss);

#endif]b4_lac_if([[if (!yyps->yynew && yyps->yyes != yyps->yyesa)

YYSTACK_FREE (yyps->yyes);]])[free (yyps);]b4_pure_if([], [[yypstate_allocated = 0;]])[

}]b4_pure_if([[#define ]b4_prefix[nerrs yyps->]b4_prefix[nerrs]])[#define yystate yyps->yystate#define yyerrstatus yyps->yyerrstatus#define yyssa yyps->yyssa#define yyss yyps->yyss#define yyssp yyps->yyssp#define yyvsa yyps->yyvsa#define yyvs yyps->yyvs#define yyvsp yyps->yyvsp]b4_locations_if([[#define yylsa yyps->yylsa#define yyls yyps->yyls#define yylsp yyps->yylsp#define yyerror_range yyps->yyerror_range]])[#define yystacksize yyps->yystacksize]b4_lac_if([[#define yyesa yyps->yyesa#define yyes yyps->yyes#define yyes_capacity yyps->yyes_capacity]])[

/*---------------.| yypush_parse. |`---------------*/

]b4_c_function_def([[yypush_parse]], [[int]],Page 24


25/33

yacc[[[yypstate *yyps]], [[yyps]]]b4_pure_if([,[[[int yypushed_char]], [[yypushed_char]]],[[[YYSTYPE const *yypushed_val]], [[yypushed_val]]]b4_locations_if([,[[[YYLTYPE *yypushed_loc]], [[yypushed_loc]]]])])m4_ifset([b4_parse_param], [,b4_parse_param]))], [[

/*----------.| yyparse. |`----------*/

#ifdef YYPARSE_PARAM]b4_c_function_def([yyparse], [int],

[[void *YYPARSE_PARAM], [YYPARSE_PARAM]])[#else /* ! YYPARSE_PARAM */]b4_c_function_def([yyparse], [int], b4_parse_param)[#endif]])[{]b4_pure_if([b4_declare_scanner_communication_variables])b4_push_if([b4_pure_if([], [[

int yypushed_char = yychar;YYSTYPE yypushed_val = yylval;]b4_locations_if([[YYLTYPE yypushed_loc = yylloc;]])

])],[b4_declare_parser_state_variables

])b4_lac_if([[int yy_lac_established = 0;]])[int yyn;int yyresult;/* Lookahead token as an internal (translated) token number. */int yytoken = 0;/* The variables used to return semantic value and location from the

action routines. */YYSTYPE yyval;]b4_locations_if([[YYLTYPE yyloc;]])[

#if YYERROR_VERBOSE/* Buffer for error messages, and its allocated size. */

char yymsgbuf[128];char *yymsg = yymsgbuf;YYSIZE_T yymsg_alloc = sizeof yymsgbuf;

#endif

#define YYPOPSTACK(N) (yyvsp -= (N), yyssp -= (N)]b4_locations_if([, yylsp -=(N)])[)

/* The number of symbols on the RHS of the reduced rule.Keep to zero when no symbol should be popped. */

int yylen = 0;]b4_push_if([[

if (!yyps->yynew){yyn = yypact[yystate];goto yyread_pushed_token;

}]])[

yyssp = yyss = yyssa;yyvsp = yyvs = yyvsa;]b4_locations_if([[yylsp = yyls = yylsa;]])[yystacksize = YYINITDEPTH;]b4_lac_if([[

yyes = yyesa;yyes_capacity = sizeof yyesa / sizeof *yyes;if (YYMAXDEPTH < yyes_capacity)

Page 25


26/33

yaccyyes_capacity = YYMAXDEPTH;]])[

YYDPRINTF ((stderr, "Starting parse\n"));

yystate = 0;yyerrstatus = 0;yynerrs = 0;yychar = YYEMPTY; /* Cause a token to be read. */

]m4_ifdef([b4_initial_action], [b4_dollar_pushdef([m4_define([b4_dollar_dollar_used])yylval], [],

[b4_push_if([b4_pure_if([*])yypushed_loc], [yylloc])])dnl/* User initialization code. */b4_user_initial_actionb4_dollar_popdef[]dnlm4_ifdef([b4_dollar_dollar_used],[[ yyvsp[0] = yylval;]])])dnlb4_locations_if([[ yylsp[0] = ]b4_push_if([b4_pure_if([*])yypushed_loc],[yylloc])[;]])dnl[ goto yysetstate;

/*------------------------------------------------------------.

| yynewstate -- Push a new state, which is found in yystate. |`------------------------------------------------------------*/yynewstate:/* In all cases, when you get here, the value and location stacks

have just been pushed. So pushing a state here evens the stacks. */yyssp++;

yysetstate:*yyssp = yystate;

if (yyss + yystacksize - 1


27/33

yacc# else

/* Extend the stack our own way. */if (YYMAXDEPTH yynew)

{]b4_use_push_for_pull_if([], [[YYDPRINTF ((stderr, "Return for a new token:\n"));]])[

Page 27


28/33

yaccyyresult = YYPUSH_MORE;goto yypushreturn;

}yyps->yynew = 0;]b4_pure_if([], [[/* Restoring the pushed token is only necessary for the first

yypush_parse invocation since subsequent invocations don't overwriteit before jumping to yyread_pushed_token. */

yychar = yypushed_char;yylval = yypushed_val;]b4_locations_if([[yylloc = yypushed_loc;]])])[

yyread_pushed_token:]])[YYDPRINTF ((stderr, "Reading a token: "));]b4_push_if([b4_pure_if([[yychar = yypushed_char;if (yypushed_val)

yylval = *yypushed_val;]b4_locations_if([[if (yypushed_loc)

yylloc = *yypushed_loc;]])])], [[yychar = YYLEX;]])[

}

if (yychar


29/33

yaccYY_IGNORE_MAYBE_UNINITIALIZED_BEGIN*++yyvsp = yylval;YY_IGNORE_MAYBE_UNINITIALIZED_END

]b4_locations_if([ *++yylsp = yylloc;])[goto yynewstate;

/*-----------------------------------------------------------.| yydefault -- do the default action for the current state. |`-----------------------------------------------------------*/yydefault:

yyn = yydefact[yystate];if (yyn == 0)

goto yyerrlab;goto yyreduce;

/*-----------------------------.| yyreduce -- Do a reduction. |`-----------------------------*/yyreduce:

/* yyn is the number of a rule to reduce with. */

yylen = yyr2[yyn];

/* If YYLEN is nonzero, implement the default value of the action:`$$ = $1'.

Otherwise, the following line sets YYVAL to garbage.This behavior is undocumented and Bisonusers should not rely upon it. Assigning to YYVALunconditionally makes the parser a bit smaller, and it avoids aGCC warning that YYVAL may be used uninitialized. */

yyval = yyvsp[1-yylen];

]b4_locations_if([[ /* Default location. */

YYLLOC_DEFAULT (yyloc, (yylsp - yylen), yylen);]])[

YY_REDUCE_PRINT (yyn);]b4_lac_if([[{int yychar_backup = yychar;switch (yyn){

]b4_user_actions[default: break;

}if (yychar_backup != yychar)YY_LAC_DISCARD ("yychar change");

}]], [[switch (yyn)

{]b4_user_actions[default: break;

}]])[/* User semantic actions sometimes alter yychar, and that requires

that yytoken be updated with the new translation. We take theapproach of translating immediately before every use of yytoken.One alternative is translating here after every semantic action,but that translation would be missed if the semantic action invokesYYABORT, YYACCEPT, or YYERROR immediately after altering yychar orif it invokes YYBACKUP. In the case of YYABORT or YYACCEPT, anincorrect destructor might then be invoked immediately. In thecase of YYERROR or YYBACKUP, subsequent parser actions might leadto an incorrect destructor call or verbose syntax error message

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yaccbefore the lookahead is translated. */

YY_SYMBOL_PRINT ("-> $$ =", yyr1[yyn], &yyval, &yyloc);

YYPOPSTACK (yylen);yylen = 0;YY_STACK_PRINT (yyss, yyssp);

*++yyvsp = yyval;]b4_locations_if([*++yylsp = yyloc;])[

/* Now `shift' the result of the reduction. Determine what statethat goes to, based on the state we popped back to and the rulenumber reduced by. */

yyn = yyr1[yyn];

yystate = yypgoto[yyn - YYNTOKENS] + *yyssp;if (0


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yacc{

yysyntax_error_status = YYSYNTAX_ERROR;yymsgp = yymsg;

}}

yyerror (]b4_yyerror_args[yymsgp);if (yysyntax_error_status == 2)goto yyexhaustedlab;

}# undef YYSYNTAX_ERROR#endif

}

]b4_locations_if([[ yyerror_range[1] = yylloc;]])[

if (yyerrstatus == 3){/* If just tried and failed to reuse lookahead token after an error, discard it. */if (yychar


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yaccyyerrlab1: yyerrstatus = 3; /* Each real token shifted decrements this. */

for (;;){yyn = yypact[yystate];if (!yypact_value_is_default (yyn))

{ yyn += YYTERROR; if (0


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yacc

#if ]b4_lac_if([[1]], [[!defined yyoverflow || YYERROR_VERBOSE]])[/*-------------------------------------------------.| yyexhaustedlab -- memory exhaustion comes here. |`-------------------------------------------------*/yyexhaustedlab:

yyerror (]b4_yyerror_args[YY_("memory exhausted"));yyresult = 2;/* Fall through. */

#endif

yyreturn:if (yychar != YYEMPTY)

{/* Make sure we have latest lookahead translation. See comments at

user semantic actions for why this is necessary. */yytoken = YYTRANSLATE (yychar);yydestruct ("Cleanup: discarding lookahead",

yytoken, &yylval]b4_locations_if([, &yylloc])[]b4_user_args[);}

/* Do not reclaim the symbols of the rule which action triggeredthis YYABORT or YYACCEPT. */

YYPOPSTACK (yylen);YY_STACK_PRINT (yyss, yyssp);while (yyssp != yyss)

{yydestruct ("Cleanup: popping", yystos[*yyssp], yyvsp]b4_locations_if([, yylsp])[]b4_user_args[);YYPOPSTACK (1);

}#ifndef yyoverflow

if (yyss != yyssa)YYSTACK_FREE (yyss);

#endif]b4_lac_if([[if (yyes != yyesa)

YYSTACK_FREE (yyes);]])b4_push_if([[yyps->yynew = 1;

yypushreturn:]])[#if YYERROR_VERBOSE

if (yymsg != yymsgbuf)YYSTACK_FREE (yymsg);

#endif/* Make sure YYID is used. */return YYID (yyresult);

}

]b4_epilogue[]dnlb4_output_end()

b4_defines_if([b4_output_begin([b4_spec_defines_file])[]b4_copyright([Bison interface for Yacc-like parsers in C],

[1984, 1989-1990, 2000-2012])[

]b4_shared_declarations[]b4_output_end()])

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