文法改进
program à
external_declaration
| program external_declaration
external_declaration à
function_definition
| declaration
function_definition à type_specifier declarator compound_statement
type_specifier à
VOID
| CHAR
| INT
| FLOAT
declarator
pointer direct_declarator
| direct_declarator
Pointerà
'*'
| '*' pointer
direct_declarator
IDENTIFIER
|direct_declarator’[‘ ‘]’
|direct_declarator ’[’ constant_expression ’]’
| IDENTIFIER '(' parameter_list ')'
| IDENTIFIER '(' ')'
|direct_declarator ‘,’ identifier_list
identifier_list
: IDENTIFIER
| identifier_list ',' IDENTIFIER
constant_expressionà
conditional_expression
parameter_list à
parameter_declaration
| parameter_list ',' parameter_declaration
parameter_declaration à
declaration_specifiers IDENTIFIER
compound_statement à
'{' '}'
| '{' statement_list '}'
| '{' declaration_list statement_list '}'
declaration_list à
declaration
| declaration_list declaration
Declarationà
init_declarator
| init_declarator_list ',' init_declarator
init_declarator à
declarator
| declarator '=' initializer
Initializer à
assignment_expression
| '{' initializer_list '}'
| '{' initializer_list ',' '}'
initializer_list à
initializer
| initializer_list ',' initializer
statement_listà
statement
| statement_list statement
Statement à
| compound_statement
| expression_statement
| selection_statement
| iteration_statement
| jump_statement
expression_statement à
';'
| expression ';'
selection_statement
: IF '(' expression ')' statement
| IF '(' expression ')' statement ELSE statement
iteration_statementà
WHILE '(' expression ')' statement
| FOR '(' expression_statement expression_statement ')' statement
| FOR '(' expression_statement expression_statement expression ')' statement
jump_statement
| CONTINUE ';'
| BREAK ';'
| RETURN ';'
| RETURN expression ';'
expression
: assignment_expression
| expression ',' assignment_expression
assignment_expression à
conditional_expression
| unary_expression assignment_operator assignment_expression
conditional_expression à
logical_or_expression
| logical_or_expression '?' expression ':' conditional_expression
logical_or_expression à
logical_and_expression
| logical_or_expression OR_OP logical_and_expression
logical_and_expression
: inclusive_or_expression
| logical_and_expression AND_OP inclusive_or_expression
inclusive_or_expressionà
exclusive_or_expression
| inclusive_or_expression '|' exclusive_or_expression
exclusive_or_expression
: and_expression
| exclusive_or_expression '^' and_expression
and_expression
: equality_expression
| and_expression '&' equality_expression
equality_expression
: relational_expression
| equality_expression EQ_OP relational_expression
| equality_expression NE_OP relational_expression
relational_expression
: shift_expression
| relational_expression '<' shift_expression
| relational_expression '>' shift_expression
| relational_expression LE_OP shift_expression
| relational_expression GE_OP shift_expression
shift_expression
: additive_expression
| shift_expression LEFT_OP additive_expression
| shift_expression RIGHT_OP additive_expression
additive_expression
: multiplicative_expression
| additive_expression '+' multiplicative_expression
| additive_expression '-' multiplicative_expression
multiplicative_expression
: cast_expression
| multiplicative_expression '*' cast_expression
| multiplicative_expression '/' cast_expression
| multiplicative_expression '%' cast_expression
cast_expression
: unary_expression
| '(' type_name ')' cast_expression
unary_expression
: postfix_expression
| INC_OP unary_expression
| DEC_OP unary_expression
| unary_operator cast_expression
| SIZEOF unary_expression
| SIZEOF '(' type_name ')'
postfix_expression à
: primary_expression
| postfix_expression '[' expression ']'
| postfix_expression '(' ')'
| postfix_expression '(' argument_expression_list ')'
| postfix_expression '.' IDENTIFIER
| postfix_expression PTR_OP IDENTIFIER
| postfix_expression INC_OP
| postfix_expression DEC_OP
primary_expression à
IDENTIFIER
| CONSTANT
| STRING_LITERAL
| '(' expression ')'
argument_expression_list
: assignment_expression
| argument_expression_list ',' assignment_expression
unary_operator
: '&'
| '*'
| '+'
| '-'
| '~'
| '!'
storage_class_specifier à
TYPEDEF
| EXTERN
| STATIC
| AUTO
| REGISTER
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
: specifier_qualifier_list struct_declarator_list ';'
specifier_qualifier_list à
type_specifier specifier_qualifier_list
| type_specifier
| type_qualifier specifier_qualifier_list
| type_qualifier
struct_declarator_list à
struct_declarator
| struct_declarator_list ',' struct_declarator
struct_declarator à
: declarator
| ':' constant_expression
| declarator ':' constant_expression
enum_specifier à
ENUM '{' enumerator_list '}'
| ENUM IDENTIFIER '{' enumerator_list '}'
| ENUM IDENTIFIER
enumerator_list à
enumerator
| enumerator_list ',' enumerator
Enumerator à
IDENTIFIER
| IDENTIFIER '=' constant_expression
type_qualifier à
CONST
| VOLATILE
type_qualifier_list à
type_qualifier
| type_qualifier_list type_qualifier
parameter_type_list à
parameter_list
| parameter_list ',' ELLIPSIS
parameter_list à
: parameter_declaration
| parameter_list ',' parameter_declaration
type_name à
specifier_qualifier_list
| specifier_qualifier_list abstract_declarator
abstract_declarator à
pointer
| direct_abstract_declarator
| pointer direct_abstract_declarator