C编译器LEX和YACC输入源文件。

/*YACC--LALR(1) PARSER*/

%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 ''
| 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
;