tps@sdchem.UUCP (03/04/87)
People keep asking me for a copy, so I am reposting a yacc grammar (actually, a complete program) for the April 1985 draft of the ANSI C standard. It finds syntax errors in its input. Oh yeah, this was originally posted by Jeff Lee. || Tom Stockfisch, UCSD Chemistry tps%chem@sdcsvax.UCSD #!/bin/sh # to extract, remove the header and type "sh filename" if `test ! -s ./Makefile` then echo "writting ./Makefile" cat > ./Makefile << '\Rogue\Monster\' YFLAGS = -dv CFLAGS = -O LFLAGS = SRC = gram.y scan.l main.c OBJ = gram.o scan.o main.o $(BIN)/ansi_c : $(OBJ) cc $(CFLAGS) $(OBJ)/ansi_c scan.o : y.tab.h clean : rm -f y.tab.h y.output *.o \Rogue\Monster\ else echo "will not over write ./Makefile" fi if `test ! -s ./README` then echo "writting ./README" cat > ./README << '\Rogue\Monster\' The files in this directory contain the ANSI C grammar from the April 30, 1985 draft of the proposed standard. This copy also incorporates all bug fixes I have seen since the last two postings. With a little work this grammar can be made to parse the C that most of us know and love (sort of). There is one bug fix to the grammar that is in this posting. On line 295 of gram.y it previously read declaration_specifiers instead of type_specifier_list as it does now. I believe the folks at the ANSI committee made a mistake since if you replace the line with what the original read you will end up with 16 shift/reduce errors and 2 reduce/reduce errors (the good ones). As it is, it only has 1 shift/reduce error that occurs on the if/else construct. YACC creates the correct parser and I don't want to ugly my grammar up. Anyway, all cumquats unite and generate this sucker. Then just sit and play with it. Remember, the grammar accepts things like "Hello, world"++; --1.23456; *'a' but this is not a bug, but simply a shuffling of the checking into the semantic analysis. If you want to hack it up to do lvalue and rvalue checking, I'm sure the ANSI committee would be glad to have your changes. Don't send'em to me though. I don't want'em. Wear this in good health. Jeff Lee gatech!jeff jeff@gatech jeff%gatech.CSNet@CSNet-Relay.ARPA \Rogue\Monster\ else echo "will not over write ./README" fi if `test ! -s ./gram.y` then echo "writting ./gram.y" cat > ./gram.y << '\Rogue\Monster\' %token IDENTIFIER CONSTANT STRING_LITERAL SIZEOF %token PTR_OP INC_OP DEC_OP LEFT_OP RIGHT_OP LE_OP GE_OP EQ_OP NE_OP %token AND_OP OR_OP MUL_ASSIGN DIV_ASSIGN MOD_ASSIGN ADD_ASSIGN %token SUB_ASSIGN LEFT_ASSIGN RIGHT_ASSIGN AND_ASSIGN %token XOR_ASSIGN OR_ASSIGN TYPE_NAME %token TYPEDEF EXTERN STATIC AUTO REGISTER %token CHAR SHORT INT LONG SIGNED UNSIGNED FLOAT DOUBLE CONST VOLATILE VOID %token STRUCT UNION ENUM ELIPSIS RANGE %token CASE DEFAULT IF ELSE SWITCH WHILE DO FOR GOTO CONTINUE BREAK RETURN %start file %% primary_expr : identifier | CONSTANT | STRING_LITERAL | '(' expr ')' ; postfix_expr : primary_expr | postfix_expr '[' expr ']' | postfix_expr '(' ')' | postfix_expr '(' argument_expr_list ')' | postfix_expr '.' identifier | postfix_expr PTR_OP identifier | postfix_expr INC_OP | postfix_expr DEC_OP ; argument_expr_list : assignment_expr | argument_expr_list ',' assignment_expr ; unary_expr : postfix_expr | INC_OP unary_expr | DEC_OP unary_expr | unary_operator cast_expr | SIZEOF unary_expr | SIZEOF '(' type_name ')' ; unary_operator : '&' | '*' | '+' | '-' | '~' | '!' ; cast_expr : unary_expr | '(' type_name ')' cast_expr ; multiplicative_expr : cast_expr | multiplicative_expr '*' cast_expr | multiplicative_expr '/' cast_expr | multiplicative_expr '%' cast_expr ; additive_expr : multiplicative_expr | additive_expr '+' multiplicative_expr | additive_expr '-' multiplicative_expr ; shift_expr : additive_expr | shift_expr LEFT_OP additive_expr | shift_expr RIGHT_OP additive_expr ; relational_expr : shift_expr | relational_expr '<' shift_expr | relational_expr '>' shift_expr | relational_expr LE_OP shift_expr | relational_expr GE_OP shift_expr ; equality_expr : relational_expr | equality_expr EQ_OP relational_expr | equality_expr NE_OP relational_expr ; and_expr : equality_expr | and_expr '&' equality_expr ; exclusive_or_expr : and_expr | exclusive_or_expr '^' and_expr ; inclusive_or_expr : exclusive_or_expr | inclusive_or_expr '|' exclusive_or_expr ; logical_and_expr : inclusive_or_expr | logical_and_expr AND_OP inclusive_or_expr ; logical_or_expr : logical_and_expr | logical_or_expr OR_OP logical_and_expr ; conditional_expr : logical_or_expr | logical_or_expr '?' logical_or_expr ':' conditional_expr ; assignment_expr : conditional_expr | unary_expr assignment_operator assignment_expr ; assignment_operator : '=' | MUL_ASSIGN | DIV_ASSIGN | MOD_ASSIGN | ADD_ASSIGN | SUB_ASSIGN | LEFT_ASSIGN | RIGHT_ASSIGN | AND_ASSIGN | XOR_ASSIGN | OR_ASSIGN ; expr : assignment_expr | expr ',' assignment_expr ; constant_expr : conditional_expr ; declaration : declaration_specifiers ';' | declaration_specifiers init_declarator_list ';' ; declaration_specifiers : storage_class_specifier | storage_class_specifier declaration_specifiers | type_specifier | type_specifier declaration_specifiers ; init_declarator_list : init_declarator | init_declarator_list ',' init_declarator ; init_declarator : declarator | declarator '=' initializer ; storage_class_specifier : TYPEDEF | EXTERN | STATIC | AUTO | REGISTER ; type_specifier : CHAR | SHORT | INT | LONG | SIGNED | UNSIGNED | FLOAT | DOUBLE | CONST | VOLATILE | VOID | struct_or_union_specifier | enum_specifier | TYPE_NAME ; struct_or_union_specifier : struct_or_union identifier '{' struct_declaration_list '}' | struct_or_union '{' struct_declaration_list '}' | struct_or_union identifier ; struct_or_union : STRUCT | UNION ; struct_declaration_list : struct_declaration | struct_declaration_list struct_declaration ; struct_declaration : type_specifier_list struct_declarator_list ';' ; struct_declarator_list : struct_declarator | struct_declarator_list ',' struct_declarator ; struct_declarator : declarator | ':' constant_expr | declarator ':' constant_expr ; enum_specifier : ENUM '{' enumerator_list '}' | ENUM identifier '{' enumerator_list '}' | ENUM identifier ; enumerator_list : enumerator | enumerator_list ',' enumerator ; enumerator : identifier | identifier '=' constant_expr ; declarator : declarator2 | pointer declarator2 ; declarator2 : identifier | '(' declarator ')' | declarator2 '[' ']' | declarator2 '[' constant_expr ']' | declarator2 '(' ')' | declarator2 '(' parameter_type_list ')' | declarator2 '(' parameter_identifier_list ')' ; pointer : '*' | '*' type_specifier_list | '*' pointer | '*' type_specifier_list pointer ; type_specifier_list : type_specifier | type_specifier_list type_specifier ; parameter_identifier_list : identifier_list | identifier_list ',' ELIPSIS ; identifier_list : identifier | identifier_list ',' identifier ; parameter_type_list : parameter_list | parameter_list ',' ELIPSIS ; parameter_list : parameter_declaration | parameter_list ',' parameter_declaration ; parameter_declaration : type_specifier_list declarator | type_name ; type_name : type_specifier_list | type_specifier_list abstract_declarator ; abstract_declarator : pointer | abstract_declarator2 | pointer abstract_declarator2 ; abstract_declarator2 : '(' abstract_declarator ')' | '[' ']' | '[' constant_expr ']' | abstract_declarator2 '[' ']' | abstract_declarator2 '[' constant_expr ']' | '(' ')' | '(' parameter_type_list ')' | abstract_declarator2 '(' ')' | abstract_declarator2 '(' parameter_type_list ')' ; initializer : assignment_expr | '{' initializer_list '}' | '{' initializer_list ',' '}' ; initializer_list : initializer | initializer_list ',' initializer ; statement : labeled_statement | compound_statement | expression_statement | selection_statement | iteration_statement | jump_statement ; labeled_statement : identifier ':' statement | CASE constant_expr ':' statement | DEFAULT ':' statement ; compound_statement : '{' '}' | '{' statement_list '}' | '{' declaration_list '}' | '{' declaration_list statement_list '}' ; declaration_list : declaration | declaration_list declaration ; statement_list : statement | statement_list statement ; expression_statement : ';' | expr ';' ; selection_statement : IF '(' expr ')' statement | IF '(' expr ')' statement ELSE statement | SWITCH '(' expr ')' statement ; iteration_statement : WHILE '(' expr ')' statement | DO statement WHILE '(' expr ')' ';' | FOR '(' ';' ';' ')' statement | FOR '(' ';' ';' expr ')' statement | FOR '(' ';' expr ';' ')' statement | FOR '(' ';' expr ';' expr ')' statement | FOR '(' expr ';' ';' ')' statement | FOR '(' expr ';' ';' expr ')' statement | FOR '(' expr ';' expr ';' ')' statement | FOR '(' expr ';' expr ';' expr ')' statement ; jump_statement : GOTO identifier ';' | CONTINUE ';' | BREAK ';' | RETURN ';' | RETURN expr ';' ; file : external_definition | file external_definition ; external_definition : function_definition | declaration ; function_definition : declarator function_body | declaration_specifiers declarator function_body ; function_body : compound_statement | declaration_list compound_statement ; identifier : IDENTIFIER ; %% #include <stdio.h> extern char yytext[]; extern int column; yyerror(s) char *s; { fflush(stdout); printf("\n%*s\n%*s\n", column, "^", column, s); } \Rogue\Monster\ else echo "will not over write ./gram.y" fi if `test ! -s ./main.c` then echo "writting ./main.c" cat > ./main.c << '\Rogue\Monster\' main() { int yyparse(); return(yyparse()); } \Rogue\Monster\ else echo "will not over write ./main.c" fi if `test ! -s ./scan.l` then echo "writting ./scan.l" cat > ./scan.l << '\Rogue\Monster\' D [0-9] L [a-zA-Z_] H [a-fA-F0-9] E [Ee][+-]?{D}+ FS (f|F|l|L) IS (u|U|l|L)* %{ #include <stdio.h> #include "y.tab.h" void count(); %} %% "/*" { comment(); } "auto" { count(); return(AUTO); } "break" { count(); return(BREAK); } "case" { count(); return(CASE); } "char" { count(); return(CHAR); } "const" { count(); return(CONST); } "continue" { count(); return(CONTINUE); } "default" { count(); return(DEFAULT); } "do" { count(); return(DO); } "double" { count(); return(DOUBLE); } "else" { count(); return(ELSE); } "enum" { count(); return(ENUM); } "extern" { count(); return(EXTERN); } "float" { count(); return(FLOAT); } "for" { count(); return(FOR); } "goto" { count(); return(GOTO); } "if" { count(); return(IF); } "int" { count(); return(INT); } "long" { count(); return(LONG); } "register" { count(); return(REGISTER); } "return" { count(); return(RETURN); } "short" { count(); return(SHORT); } "signed" { count(); return(SIGNED); } "sizeof" { count(); return(SIZEOF); } "static" { count(); return(STATIC); } "struct" { count(); return(STRUCT); } "switch" { count(); return(SWITCH); } "typedef" { count(); return(TYPEDEF); } "union" { count(); return(UNION); } "unsigned" { count(); return(UNSIGNED); } "void" { count(); return(VOID); } "volatile" { count(); return(VOLATILE); } "while" { count(); return(WHILE); } {L}({L}|{D})* { count(); return(check_type()); } 0[xX]{H}+{IS}? { count(); return(CONSTANT); } 0[xX]{H}+{IS}? { count(); return(CONSTANT); } 0{D}+{IS}? { count(); return(CONSTANT); } 0{D}+{IS}? { count(); return(CONSTANT); } {D}+{IS}? { count(); return(CONSTANT); } {D}+{IS}? { count(); return(CONSTANT); } '(\\.|[^\\'])+' { count(); return(CONSTANT); } {D}+{E}{FS}? { count(); return(CONSTANT); } {D}*"."{D}+({E})?{FS}? { count(); return(CONSTANT); } {D}+"."{D}*({E})?{FS}? { count(); return(CONSTANT); } \"(\\.|[^\\"])*\" { count(); return(STRING_LITERAL); } ">>=" { count(); return(RIGHT_ASSIGN); } "<<=" { count(); return(LEFT_ASSIGN); } "+=" { count(); return(ADD_ASSIGN); } "-=" { count(); return(SUB_ASSIGN); } "*=" { count(); return(MUL_ASSIGN); } "/=" { count(); return(DIV_ASSIGN); } "%=" { count(); return(MOD_ASSIGN); } "&=" { count(); return(AND_ASSIGN); } "^=" { count(); return(XOR_ASSIGN); } "|=" { count(); return(OR_ASSIGN); } ">>" { count(); return(RIGHT_OP); } "<<" { count(); return(LEFT_OP); } "++" { count(); return(INC_OP); } "--" { count(); return(DEC_OP); } "->" { count(); return(PTR_OP); } "&&" { count(); return(AND_OP); } "||" { count(); return(OR_OP); } "<=" { count(); return(LE_OP); } ">=" { count(); return(GE_OP); } "==" { count(); return(EQ_OP); } "!=" { count(); return(NE_OP); } ";" { count(); return(';'); } "{" { count(); return('{'); } "}" { count(); return('}'); } "," { count(); return(','); } ":" { count(); return(':'); } "=" { count(); return('='); } "(" { count(); return('('); } ")" { count(); return(')'); } "[" { count(); return('['); } "]" { count(); return(']'); } "." { count(); return('.'); } "&" { count(); return('&'); } "!" { count(); return('!'); } "~" { count(); return('~'); } "-" { count(); return('-'); } "+" { count(); return('+'); } "*" { count(); return('*'); } "/" { count(); return('/'); } "%" { count(); return('%'); } "<" { count(); return('<'); } ">" { count(); return('>'); } "^" { count(); return('^'); } "|" { count(); return('|'); } "?" { count(); return('?'); } [ \t\v\n\f] { count(); } . { /* ignore bad characters */ } %% yywrap() { return(1); } comment() { char c, c1; loop: while ((c = input()) != '*' && c != 0) putchar(c); if ((c1 = input()) != '/' && c != 0) { unput(c1); goto loop; } if (c != 0) putchar(c1); } int column = 0; void count() { int i; for (i = 0; yytext[i] != '\0'; i++) if (yytext[i] == '\n') column = 0; else if (yytext[i] == '\t') column += 8 - (column % 8); else column++; ECHO; } int check_type() { /* * pseudo code --- this is what it should check * * if (yytext == type_name) * return(TYPE_NAME); * * return(IDENTIFIER); */ /* * it actually will only return IDENTIFIER */ return(IDENTIFIER); } \Rogue\Monster\ else echo "will not over write ./scan.l" fi if `test ! -s ./y.tab.h` then echo "writting ./y.tab.h" cat > ./y.tab.h << '\Rogue\Monster\' # define IDENTIFIER 257 # define CONSTANT 258 # define STRING_LITERAL 259 # define SIZEOF 260 # define PTR_OP 261 # define INC_OP 262 # define DEC_OP 263 # define LEFT_OP 264 # define RIGHT_OP 265 # define LE_OP 266 # define GE_OP 267 # define EQ_OP 268 # define NE_OP 269 # define AND_OP 270 # define OR_OP 271 # define MUL_ASSIGN 272 # define DIV_ASSIGN 273 # define MOD_ASSIGN 274 # define ADD_ASSIGN 275 # define SUB_ASSIGN 276 # define LEFT_ASSIGN 277 # define RIGHT_ASSIGN 278 # define AND_ASSIGN 279 # define XOR_ASSIGN 280 # define OR_ASSIGN 281 # define TYPE_NAME 282 # define TYPEDEF 283 # define EXTERN 284 # define STATIC 285 # define AUTO 286 # define REGISTER 287 # define CHAR 288 # define SHORT 289 # define INT 290 # define LONG 291 # define SIGNED 292 # define UNSIGNED 293 # define FLOAT 294 # define DOUBLE 295 # define CONST 296 # define VOLATILE 297 # define VOID 298 # define STRUCT 299 # define UNION 300 # define ENUM 301 # define ELIPSIS 302 # define RANGE 303 # define CASE 304 # define DEFAULT 305 # define IF 306 # define ELSE 307 # define SWITCH 308 # define WHILE 309 # define DO 310 # define FOR 311 # define GOTO 312 # define CONTINUE 313 # define BREAK 314 # define RETURN 315 \Rogue\Monster\ else echo "will not over write ./y.tab.h" fi echo "Finished archive 1 of 1" exit || Tom Stockfisch, UCSD Chemistry tps%chem@sdcsvax.UCSD