X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=parser.c;h=5ae71c750e5b785bf76e87b28307ca91c1c6c7a2;hb=ac85b60f9b068316821a99491291703703563512;hp=bac60ce65e0689a21c246afd1762626b80436eb0;hpb=f4997f4d3a17361c4a6e7beaec96f76caecd1e51;p=cparser diff --git a/parser.c b/parser.c index bac60ce..5ae71c7 100644 --- a/parser.c +++ b/parser.c @@ -14,12 +14,12 @@ #include "type_hash.h" #include "ast_t.h" #include "lang_features.h" +#include "warning.h" #include "adt/bitfiddle.h" #include "adt/error.h" #include "adt/array.h" //#define PRINT_TOKENS -//#define ABORT_ON_ERROR #define MAX_LOOKAHEAD 2 typedef struct { @@ -50,6 +50,8 @@ static declaration_t *last_declaration = NULL; static declaration_t *current_function = NULL; static switch_statement_t *current_switch = NULL; static statement_t *current_loop = NULL; +static goto_statement_t *goto_first = NULL; +static goto_statement_t *goto_last = NULL; static struct obstack temp_obst; /** The current source position. */ @@ -134,6 +136,13 @@ static void *allocate_ast_zero(size_t size) return res; } +static declaration_t *allocate_declaration_zero(void) +{ + declaration_t *declaration = allocate_ast_zero(sizeof(*allocate_declaration_zero())); + declaration->type = type_error_type; + return declaration; +} + /** * Returns the size of a statement node. * @@ -227,7 +236,8 @@ static expression_t *allocate_expression_zero(expression_kind_t kind) size_t size = get_expression_struct_size(kind); expression_t *res = allocate_ast_zero(size); - res->base.kind = kind; + res->base.kind = kind; + res->base.datatype = type_error_type; return res; } @@ -461,14 +471,6 @@ static void eat_paren(void) } \ next_token(); -#define expect_fail(expected) \ - if(UNLIKELY(token.type != (expected))) { \ - parse_error_expected(NULL, (expected), 0); \ - eat_statement(); \ - goto fail; \ - } \ - next_token(); - #define expect_block(expected) \ if(UNLIKELY(token.type != (expected))) { \ parse_error_expected(NULL, (expected), 0); \ @@ -637,15 +639,13 @@ static int get_rank(const type_t *type) return ATOMIC_TYPE_INT; assert(type->kind == TYPE_ATOMIC); - const atomic_type_t *atomic_type = &type->atomic; - atomic_type_kind_t atype = atomic_type->akind; - return atype; + return type->atomic.akind; } static type_t *promote_integer(type_t *type) { if(type->kind == TYPE_BITFIELD) - return promote_integer(type->bitfield.base); + type = type->bitfield.base; if(get_rank(type) < ATOMIC_TYPE_INT) type = type_int; @@ -702,109 +702,40 @@ static bool is_null_pointer_constant(const expression_t *expression) static expression_t *create_implicit_cast(expression_t *expression, type_t *dest_type) { - type_t *source_type = expression->base.datatype; + type_t *const source_type = expression->base.datatype; - if(source_type == NULL) + if (source_type == dest_type) return expression; - source_type = skip_typeref(source_type); - dest_type = skip_typeref(dest_type); - - if(source_type == dest_type) - return expression; - - switch (dest_type->kind) { - case TYPE_ENUM: - /* TODO warning for implicitly converting to enum */ - case TYPE_BITFIELD: - case TYPE_ATOMIC: - if (source_type->kind != TYPE_ATOMIC && - source_type->kind != TYPE_ENUM && - source_type->kind != TYPE_BITFIELD) { - panic("casting of non-atomic types not implemented yet"); - } - - if(is_type_floating(dest_type) && !is_type_scalar(source_type)) { - type_error_incompatible("can't cast types", - expression->base.source_position, source_type, - dest_type); - return expression; - } - - return create_cast_expression(expression, dest_type); - - case TYPE_POINTER: - switch (source_type->kind) { - case TYPE_ATOMIC: - if (is_null_pointer_constant(expression)) { - return create_cast_expression(expression, dest_type); - } - break; - - case TYPE_POINTER: - if (pointers_compatible(source_type, dest_type)) { - return create_cast_expression(expression, dest_type); - } - break; - - case TYPE_ARRAY: { - array_type_t *array_type = &source_type->array; - pointer_type_t *pointer_type = &dest_type->pointer; - if (types_compatible(array_type->element_type, - pointer_type->points_to)) { - return create_cast_expression(expression, dest_type); - } - break; - } - - default: - panic("casting of non-atomic types not implemented yet"); - } - - type_error_incompatible("can't implicitly cast types", - expression->base.source_position, source_type, dest_type); - return expression; - - default: - panic("casting of non-atomic types not implemented yet"); - } + return create_cast_expression(expression, dest_type); } /** Implements the rules from § 6.5.16.1 */ -static void semantic_assign(type_t *orig_type_left, expression_t **right, +static type_t *semantic_assign(type_t *orig_type_left, + const expression_t *const right, const char *context) { - type_t *orig_type_right = (*right)->base.datatype; - - if(orig_type_right == NULL) - return; - - type_t *const type_left = skip_typeref(orig_type_left); - type_t *const type_right = skip_typeref(orig_type_right); + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) || - (is_type_pointer(type_left) && is_null_pointer_constant(*right)) || + (is_type_pointer(type_left) && is_null_pointer_constant(right)) || (is_type_atomic(type_left, ATOMIC_TYPE_BOOL) && is_type_pointer(type_right))) { - *right = create_implicit_cast(*right, type_left); - return; + return orig_type_left; } if (is_type_pointer(type_left) && is_type_pointer(type_right)) { - pointer_type_t *pointer_type_left = &type_left->pointer; - pointer_type_t *pointer_type_right = &type_right->pointer; - type_t *points_to_left = pointer_type_left->points_to; - type_t *points_to_right = pointer_type_right->points_to; - - points_to_left = skip_typeref(points_to_left); - points_to_right = skip_typeref(points_to_right); + type_t *points_to_left = skip_typeref(type_left->pointer.points_to); + type_t *points_to_right = skip_typeref(type_right->pointer.points_to); /* the left type has all qualifiers from the right type */ unsigned missing_qualifiers = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers; if(missing_qualifiers != 0) { errorf(HERE, "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointed-to type", type_left, context, type_right, missing_qualifiers); - return; + return orig_type_left; } points_to_left = get_unqualified_type(points_to_left); @@ -813,23 +744,27 @@ static void semantic_assign(type_t *orig_type_left, expression_t **right, if(!is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) && !is_type_atomic(points_to_right, ATOMIC_TYPE_VOID) && !types_compatible(points_to_left, points_to_right)) { - goto incompatible_assign_types; + return NULL; } - *right = create_implicit_cast(*right, type_left); - return; + return orig_type_left; } - if (is_type_compound(type_left) - && types_compatible(type_left, type_right)) { - *right = create_implicit_cast(*right, type_left); - return; + if (is_type_compound(type_left) && is_type_compound(type_right)) { + type_t *const unqual_type_left = get_unqualified_type(type_left); + type_t *const unqual_type_right = get_unqualified_type(type_right); + if (types_compatible(unqual_type_left, unqual_type_right)) { + return orig_type_left; + } } -incompatible_assign_types: - /* TODO: improve error message */ - errorf(HERE, "incompatible types in %s", context); - errorf(HERE, "'%T' <- '%T'", orig_type_left, orig_type_right); + if (!is_type_valid(type_left)) + return type_left; + + if (!is_type_valid(type_right)) + return orig_type_right; + + return NULL; } static expression_t *parse_constant_expression(void) @@ -854,7 +789,7 @@ static type_t *make_global_typedef(const char *name, type_t *type) { symbol_t *const symbol = symbol_table_insert(name); - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); + declaration_t *const declaration = allocate_declaration_zero(); declaration->namespc = NAMESPACE_NORMAL; declaration->storage_class = STORAGE_CLASS_TYPEDEF; declaration->type = type; @@ -869,15 +804,15 @@ static type_t *make_global_typedef(const char *name, type_t *type) return typedef_type; } -static const char *parse_string_literals(void) +static string_t parse_string_literals(void) { assert(token.type == T_STRING_LITERAL); - const char *result = token.v.string; + string_t result = token.v.string; next_token(); - while(token.type == T_STRING_LITERAL) { - result = concat_strings(result, token.v.string); + while (token.type == T_STRING_LITERAL) { + result = concat_strings(&result, &token.v.string); next_token(); } @@ -980,13 +915,13 @@ static designator_t *parse_designation(void) #endif static initializer_t *initializer_from_string(array_type_t *type, - const char *string) + const string_t *const string) { /* TODO: check len vs. size of array type */ (void) type; initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING); - initializer->string.string = string; + initializer->string.string = *string; return initializer; } @@ -1020,7 +955,7 @@ static initializer_t *initializer_from_expression(type_t *type, case EXPR_STRING_LITERAL: if (element_type->atomic.akind == ATOMIC_TYPE_CHAR) { return initializer_from_string(array_type, - expression->string.value); + &expression->string.value); } case EXPR_WIDE_STRING_LITERAL: { @@ -1037,33 +972,27 @@ static initializer_t *initializer_from_expression(type_t *type, } } - type_t *expression_type = skip_typeref(expression->base.datatype); - if(is_type_scalar(type) || types_compatible(type, expression_type)) { - semantic_assign(type, &expression, "initializer"); - - initializer_t *result = allocate_initializer_zero(INITIALIZER_VALUE); - result->value.value = expression; + type_t *const res_type = semantic_assign(type, expression, "initializer"); + if (res_type == NULL) + return NULL; - return result; - } + initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE); + result->value.value = create_implicit_cast(expression, res_type); - return NULL; + return result; } static initializer_t *parse_sub_initializer(type_t *type, - expression_t *expression, - type_t *expression_type); + expression_t *expression); static initializer_t *parse_sub_initializer_elem(type_t *type) { if(token.type == '{') { - return parse_sub_initializer(type, NULL, NULL); + return parse_sub_initializer(type, NULL); } - expression_t *expression = parse_assignment_expression(); - type_t *expression_type = skip_typeref(expression->base.datatype); - - return parse_sub_initializer(type, expression, expression_type); + expression_t *expression = parse_assignment_expression(); + return parse_sub_initializer(type, expression); } static bool had_initializer_brace_warning; @@ -1087,8 +1016,7 @@ static void skip_designator(void) } static initializer_t *parse_sub_initializer(type_t *type, - expression_t *expression, - type_t *expression_type) + expression_t *expression) { if(is_type_scalar(type)) { /* there might be extra {} hierarchies */ @@ -1098,7 +1026,7 @@ static initializer_t *parse_sub_initializer(type_t *type, warningf(HERE, "braces around scalar initializer"); had_initializer_brace_warning = true; } - initializer_t *result = parse_sub_initializer(type, NULL, NULL); + initializer_t *result = parse_sub_initializer(type, NULL); if(token.type == ',') { next_token(); /* TODO: warn about excessive elements */ @@ -1130,10 +1058,6 @@ static initializer_t *parse_sub_initializer(type_t *type, initializer_t *result = NULL; initializer_t **elems; if(is_type_array(type)) { - array_type_t *array_type = &type->array; - type_t *element_type = array_type->element_type; - element_type = skip_typeref(element_type); - if(token.type == '.') { errorf(HERE, "compound designator in initializer for array type '%T'", @@ -1141,13 +1065,14 @@ static initializer_t *parse_sub_initializer(type_t *type, skip_designator(); } + type_t *const element_type = skip_typeref(type->array.element_type); + initializer_t *sub; had_initializer_brace_warning = false; if(expression == NULL) { sub = parse_sub_initializer_elem(element_type); } else { - sub = parse_sub_initializer(element_type, expression, - expression_type); + sub = parse_sub_initializer(element_type, expression); } /* didn't match the subtypes -> try the parent type */ @@ -1177,8 +1102,7 @@ static initializer_t *parse_sub_initializer(type_t *type, } } else { assert(is_type_compound(type)); - compound_type_t *compound_type = &type->compound; - context_t *context = &compound_type->declaration->context; + context_t *const context = &type->compound.declaration->context; if(token.type == '[') { errorf(HERE, @@ -1198,7 +1122,7 @@ static initializer_t *parse_sub_initializer(type_t *type, if(expression == NULL) { sub = parse_sub_initializer_elem(first_type); } else { - sub = parse_sub_initializer(first_type, expression,expression_type); + sub = parse_sub_initializer(first_type, expression); } /* didn't match the subtypes -> try our parent type */ @@ -1257,17 +1181,19 @@ static initializer_t *parse_sub_initializer(type_t *type, return result; } -static initializer_t *parse_initializer(type_t *type) +static initializer_t *parse_initializer(type_t *const orig_type) { initializer_t *result; - type = skip_typeref(type); + type_t *const type = skip_typeref(orig_type); if(token.type != '{') { expression_t *expression = parse_assignment_expression(); initializer_t *initializer = initializer_from_expression(type, expression); if(initializer == NULL) { - errorf(HERE, "initializer expression '%E', type '%T' is incompatible with type '%T'", expression, expression->base.datatype, type); + errorf(HERE, + "initializer expression '%E' of type '%T' is incompatible with type '%T'", + expression, expression->base.datatype, orig_type); } return initializer; } @@ -1285,7 +1211,7 @@ static initializer_t *parse_initializer(type_t *type) expect('}'); return result; } else { - result = parse_sub_initializer(type, NULL, NULL); + result = parse_sub_initializer(type, NULL); } return result; @@ -1331,13 +1257,9 @@ static declaration_t *parse_compound_type_specifier(bool is_struct) } if(declaration == NULL) { - declaration = allocate_ast_zero(sizeof(declaration[0])); - - if(is_struct) { - declaration->namespc = NAMESPACE_STRUCT; - } else { - declaration->namespc = NAMESPACE_UNION; - } + declaration = allocate_declaration_zero(); + declaration->namespc = + (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION); declaration->source_position = token.source_position; declaration->symbol = symbol; declaration->parent_context = context; @@ -1371,7 +1293,7 @@ static declaration_t *parse_compound_type_specifier(bool is_struct) return declaration; } -static void parse_enum_entries(enum_type_t *const enum_type) +static void parse_enum_entries(type_t *const enum_type) { eat('{'); @@ -1382,15 +1304,15 @@ static void parse_enum_entries(enum_type_t *const enum_type) } do { - declaration_t *entry = allocate_ast_zero(sizeof(entry[0])); - if(token.type != T_IDENTIFIER) { parse_error_expected("while parsing enum entry", T_IDENTIFIER, 0); eat_block(); return; } + + declaration_t *const entry = allocate_declaration_zero(); entry->storage_class = STORAGE_CLASS_ENUM_ENTRY; - entry->type = (type_t*) enum_type; + entry->type = enum_type; entry->symbol = token.v.symbol; entry->source_position = token.source_position; next_token(); @@ -1434,9 +1356,8 @@ static type_t *parse_enum_specifier(void) } if(declaration == NULL) { - declaration = allocate_ast_zero(sizeof(declaration[0])); - - declaration->namespc = NAMESPACE_ENUM; + declaration = allocate_declaration_zero(); + declaration->namespc = NAMESPACE_ENUM; declaration->source_position = token.source_position; declaration->symbol = symbol; declaration->parent_context = context; @@ -1455,7 +1376,7 @@ static type_t *parse_enum_specifier(void) append_declaration(declaration); declaration->init.is_defined = 1; - parse_enum_entries(&type->enumt); + parse_enum_entries(type); parse_attributes(); } @@ -1677,7 +1598,7 @@ static void parse_declaration_specifiers(declaration_specifiers_t *specifiers) } break; - /* TODO: if type != NULL for the following rules should issue + /* TODO: if is_type_valid(type) for the following rules should issue * an error */ case T_struct: { type = allocate_type_zero(TYPE_COMPOUND_STRUCT); @@ -1820,7 +1741,9 @@ finish_specifiers: /* invalid specifier combination, give an error message */ if(type_specifiers == 0) { if (! strict_mode) { - warningf(HERE, "no type specifiers in declaration, using int"); + if (warning.implicit_int) { + warningf(HERE, "no type specifiers in declaration, using 'int'"); + } atomic_type = ATOMIC_TYPE_INT; break; } else { @@ -1878,8 +1801,7 @@ static declaration_t *parse_identifier_list(void) declaration_t *declarations = NULL; declaration_t *last_declaration = NULL; do { - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); - + declaration_t *const declaration = allocate_declaration_zero(); declaration->source_position = token.source_position; declaration->symbol = token.v.symbol; next_token(); @@ -1910,16 +1832,13 @@ static void semantic_parameter(declaration_t *declaration) errorf(HERE, "parameter may only have none or register storage class"); } - type_t *orig_type = declaration->type; - if(orig_type == NULL) - return; - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = declaration->type; + type_t * type = skip_typeref(orig_type); /* Array as last part of a parameter type is just syntactic sugar. Turn it * into a pointer. § 6.7.5.3 (7) */ if (is_type_array(type)) { - const array_type_t *arr_type = &type->array; - type_t *element_type = arr_type->element_type; + type_t *const element_type = type->array.element_type; type = make_pointer_type(element_type, type->base.qualifiers); @@ -2229,7 +2148,16 @@ static type_t *construct_declarator_type(construct_type_t *construct_list, function_type->function.return_type = type; - type = function_type; + type_t *skipped_return_type = skip_typeref(type); + if (is_type_function(skipped_return_type)) { + errorf(HERE, "function returning function is not allowed"); + type = type_error_type; + } else if (is_type_array(skipped_return_type)) { + errorf(HERE, "function returning array is not allowed"); + type = type_error_type; + } else { + type = function_type; + } break; } @@ -2253,7 +2181,13 @@ static type_t *construct_declarator_type(construct_type_t *construct_list, array_type->array.is_variable = parsed_array->is_variable; array_type->array.size = parsed_array->size; - type = array_type; + type_t *skipped_type = skip_typeref(type); + if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) { + errorf(HERE, "array of void is not allowed"); + type = type_error_type; + } else { + type = array_type; + } break; } } @@ -2275,14 +2209,14 @@ static type_t *construct_declarator_type(construct_type_t *construct_list, static declaration_t *parse_declarator( const declaration_specifiers_t *specifiers, bool may_be_abstract) { - type_t *type = specifiers->type; - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); + declaration_t *const declaration = allocate_declaration_zero(); declaration->storage_class = specifiers->storage_class; declaration->modifiers = specifiers->decl_modifiers; declaration->is_inline = specifiers->is_inline; construct_type_t *construct_type = parse_inner_declarator(declaration, may_be_abstract); + type_t *const type = specifiers->type; declaration->type = construct_declarator_type(construct_type, type); if(construct_type != NULL) { @@ -2315,6 +2249,11 @@ static declaration_t *append_declaration(declaration_t* const declaration) return declaration; } +static bool is_sym_main(const symbol_t *const sym) +{ + return strcmp(sym->string, "main") == 0; +} + static declaration_t *internal_record_declaration( declaration_t *const declaration, const bool is_function_definition) @@ -2323,7 +2262,9 @@ static declaration_t *internal_record_declaration( const namespace_t namespc = (namespace_t)declaration->namespc; const type_t *const type = skip_typeref(declaration->type); - if (is_type_function(type) && type->function.unspecified_parameters) { + if (is_type_function(type) && + type->function.unspecified_parameters && + warning.strict_prototypes) { warningf(declaration->source_position, "function declaration '%#T' is not a prototype", type, declaration->symbol); @@ -2331,68 +2272,84 @@ static declaration_t *internal_record_declaration( declaration_t *const previous_declaration = get_declaration(symbol, namespc); assert(declaration != previous_declaration); - if (previous_declaration != NULL - && previous_declaration->parent_context == context) { - /* can happen for K&R style declarations */ - if(previous_declaration->type == NULL) { - previous_declaration->type = declaration->type; - } - - const type_t *const prev_type = skip_typeref(previous_declaration->type); - if (!types_compatible(type, prev_type)) { - errorf(declaration->source_position, - "declaration '%#T' is incompatible with previous declaration '%#T'", - type, symbol, previous_declaration->type, symbol); - errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); - } else { - unsigned old_storage_class = previous_declaration->storage_class; - unsigned new_storage_class = declaration->storage_class; - - /* pretend no storage class means extern for function declarations - * (except if the previous declaration is neither none nor extern) */ - if (is_type_function(type)) { - switch (old_storage_class) { - case STORAGE_CLASS_NONE: - old_storage_class = STORAGE_CLASS_EXTERN; - - case STORAGE_CLASS_EXTERN: - if (new_storage_class == STORAGE_CLASS_NONE && !is_function_definition) { - new_storage_class = STORAGE_CLASS_EXTERN; - } - break; + if (previous_declaration != NULL) { + if (previous_declaration->parent_context == context) { + /* can happen for K&R style declarations */ + if(previous_declaration->type == NULL) { + previous_declaration->type = declaration->type; + } - default: break; + const type_t *const prev_type = skip_typeref(previous_declaration->type); + if (!types_compatible(type, prev_type)) { + errorf(declaration->source_position, + "declaration '%#T' is incompatible with previous declaration '%#T'", + type, symbol, previous_declaration->type, symbol); + errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); + } else { + unsigned old_storage_class = previous_declaration->storage_class; + unsigned new_storage_class = declaration->storage_class; + + /* pretend no storage class means extern for function declarations + * (except if the previous declaration is neither none nor extern) */ + if (is_type_function(type)) { + switch (old_storage_class) { + case STORAGE_CLASS_NONE: + old_storage_class = STORAGE_CLASS_EXTERN; + + case STORAGE_CLASS_EXTERN: + if (is_function_definition) { + if (warning.missing_prototypes && + prev_type->function.unspecified_parameters && + !is_sym_main(symbol)) { + warningf(declaration->source_position, "no previous prototype for '%#T'", type, symbol); + } + } else if (new_storage_class == STORAGE_CLASS_NONE) { + new_storage_class = STORAGE_CLASS_EXTERN; + } + break; + + default: break; + } } - } - if (old_storage_class == STORAGE_CLASS_EXTERN && - new_storage_class == STORAGE_CLASS_EXTERN) { + if (old_storage_class == STORAGE_CLASS_EXTERN && + new_storage_class == STORAGE_CLASS_EXTERN) { warn_redundant_declaration: - warningf(declaration->source_position, "redundant declaration for '%Y'", symbol); - warningf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); - } else if (current_function == NULL) { - if (old_storage_class != STORAGE_CLASS_STATIC && - new_storage_class == STORAGE_CLASS_STATIC) { - errorf(declaration->source_position, "static declaration of '%Y' follows non-static declaration", symbol); - errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); - } else { - if (old_storage_class != STORAGE_CLASS_EXTERN) { - goto warn_redundant_declaration; + if (warning.redundant_decls) { + warningf(declaration->source_position, "redundant declaration for '%Y'", symbol); + warningf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); } - if (new_storage_class == STORAGE_CLASS_NONE) { - previous_declaration->storage_class = STORAGE_CLASS_NONE; + } else if (current_function == NULL) { + if (old_storage_class != STORAGE_CLASS_STATIC && + new_storage_class == STORAGE_CLASS_STATIC) { + errorf(declaration->source_position, "static declaration of '%Y' follows non-static declaration", symbol); + errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); + } else { + if (old_storage_class != STORAGE_CLASS_EXTERN && !is_function_definition) { + goto warn_redundant_declaration; + } + if (new_storage_class == STORAGE_CLASS_NONE) { + previous_declaration->storage_class = STORAGE_CLASS_NONE; + } } - } - } else { - if (old_storage_class == new_storage_class) { - errorf(declaration->source_position, "redeclaration of '%Y'", symbol); } else { - errorf(declaration->source_position, "redeclaration of '%Y' with different linkage", symbol); + if (old_storage_class == new_storage_class) { + errorf(declaration->source_position, "redeclaration of '%Y'", symbol); + } else { + errorf(declaration->source_position, "redeclaration of '%Y' with different linkage", symbol); + } + errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); } - errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol); } + return previous_declaration; + } + } else if (is_function_definition && + declaration->storage_class != STORAGE_CLASS_STATIC) { + if (warning.missing_prototypes && !is_sym_main(symbol)) { + warningf(declaration->source_position, "no previous prototype for '%#T'", type, symbol); + } else if (warning.missing_declarations && !is_sym_main(symbol)) { + warningf(declaration->source_position, "no previous declaration for '%#T'", type, symbol); } - return previous_declaration; } assert(declaration->parent_context == NULL); @@ -2410,7 +2367,7 @@ static declaration_t *record_declaration(declaration_t *declaration) return internal_record_declaration(declaration, false); } -static declaration_t *record_function_definition(declaration_t *const declaration) +static declaration_t *record_function_definition(declaration_t *declaration) { return internal_record_declaration(declaration, true); } @@ -2448,9 +2405,7 @@ static void parse_init_declarator_rest(declaration_t *declaration) eat('='); type_t *orig_type = declaration->type; - type_t *type = NULL; - if(orig_type != NULL) - type = skip_typeref(orig_type); + type_t *type = type = skip_typeref(orig_type); if(declaration->init.initializer != NULL) { parser_error_multiple_definition(declaration, token.source_position); @@ -2460,7 +2415,7 @@ static void parse_init_declarator_rest(declaration_t *declaration) /* § 6.7.5 (22) array initializers for arrays with unknown size determine * the array type size */ - if(type != NULL && is_type_array(type) && initializer != NULL) { + if(is_type_array(type) && initializer != NULL) { array_type_t *array_type = &type->array; if(array_type->size == NULL) { @@ -2470,20 +2425,17 @@ static void parse_init_declarator_rest(declaration_t *declaration) switch (initializer->kind) { case INITIALIZER_LIST: { - initializer_list_t *const list = &initializer->list; - cnst->conste.v.int_value = list->len; + cnst->conste.v.int_value = initializer->list.len; break; } case INITIALIZER_STRING: { - initializer_string_t *const string = &initializer->string; - cnst->conste.v.int_value = strlen(string->string) + 1; + cnst->conste.v.int_value = initializer->string.string.size; break; } case INITIALIZER_WIDE_STRING: { - initializer_wide_string_t *const string = &initializer->wide_string; - cnst->conste.v.int_value = string->string.size; + cnst->conste.v.int_value = initializer->wide_string.string.size; break; } @@ -2495,7 +2447,7 @@ static void parse_init_declarator_rest(declaration_t *declaration) } } - if(type != NULL && is_type_function(type)) { + if(is_type_function(type)) { errorf(declaration->source_position, "initializers not allowed for function types at declator '%Y' (type '%T')", declaration->symbol, orig_type); @@ -2511,8 +2463,7 @@ static void parse_anonymous_declaration_rest( { eat(';'); - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); - + declaration_t *const declaration = allocate_declaration_zero(); declaration->type = specifiers->type; declaration->storage_class = specifiers->storage_class; declaration->source_position = specifiers->source_position; @@ -2525,8 +2476,7 @@ static void parse_anonymous_declaration_rest( switch (type->kind) { case TYPE_COMPOUND_STRUCT: case TYPE_COMPOUND_UNION: { - const compound_type_t *compound_type = &type->compound; - if (compound_type->declaration->symbol == NULL) { + if (type->compound.declaration->symbol == NULL) { warningf(declaration->source_position, "unnamed struct/union that defines no instances"); } break; @@ -2553,7 +2503,9 @@ static void parse_declaration_rest(declaration_t *ndeclaration, type_t *orig_type = declaration->type; type_t *type = skip_typeref(orig_type); - if(type->kind != TYPE_FUNCTION && declaration->is_inline) { + if (type->kind != TYPE_FUNCTION && + declaration->is_inline && + is_type_valid(type)) { warningf(declaration->source_position, "variable '%Y' declared 'inline'\n", declaration->symbol); } @@ -2662,8 +2614,10 @@ static void parse_kr_declaration_list(declaration_t *declaration) errorf(HERE, "no type specified for function parameter '%Y'", parameter_declaration->symbol); } else { - warningf(HERE, "no type specified for function parameter '%Y', using int", - parameter_declaration->symbol); + if (warning.implicit_int) { + warningf(HERE, "no type specified for function parameter '%Y', using 'int'", + parameter_declaration->symbol); + } parameter_type = type_int; parameter_declaration->type = parameter_type; } @@ -2694,6 +2648,31 @@ static void parse_kr_declaration_list(declaration_t *declaration) declaration->type = type; } +/** + * Check if all labels are defined in the current function. + */ +static void check_for_missing_labels(void) +{ + bool first_err = true; + for (const goto_statement_t *goto_statement = goto_first; + goto_statement != NULL; + goto_statement = goto_statement->next) { + const declaration_t *label = goto_statement->label; + + if (label->source_position.input_name == NULL) { + if (first_err) { + first_err = false; + diagnosticf("%s: In function '%Y':\n", + current_function->source_position.input_name, + current_function->symbol); + } + errorf(goto_statement->statement.source_position, + "label '%Y' used but not defined", label->symbol); + } + } + goto_first = goto_last = NULL; +} + static void parse_external_declaration(void) { /* function-definitions and declarations both start with declaration @@ -2727,16 +2706,14 @@ static void parse_external_declaration(void) } type_t *type = ndeclaration->type; - if(type == NULL) { - eat_block(); - return; - } /* note that we don't skip typerefs: the standard doesn't allow them here * (so we can't use is_type_function here) */ if(type->kind != TYPE_FUNCTION) { - errorf(HERE, "declarator '%#T' has a body but is not a function type", - type, ndeclaration->symbol); + if (is_type_valid(type)) { + errorf(HERE, "declarator '%#T' has a body but is not a function type", + type, ndeclaration->symbol); + } eat_block(); return; } @@ -2787,6 +2764,7 @@ static void parse_external_declaration(void) current_function = declaration; declaration->init.statement = parse_compound_statement(); + check_for_missing_labels(); assert(current_function == declaration); current_function = old_current_function; @@ -2822,15 +2800,12 @@ static void parse_struct_declarators(const declaration_specifiers_t *specifiers) type_t *type = make_bitfield_type(base_type, size); - declaration = allocate_ast_zero(sizeof(declaration[0])); - + declaration = allocate_declaration_zero(); declaration->namespc = NAMESPACE_NORMAL; declaration->storage_class = STORAGE_CLASS_NONE; declaration->source_position = token.source_position; declaration->modifiers = specifiers->decl_modifiers; declaration->type = type; - - record_declaration(declaration); } else { declaration = parse_declarator(specifiers,/*may_be_abstract=*/true); @@ -2912,10 +2887,15 @@ static expression_t *create_invalid_expression(void) return expression; } +/** + * Prints an error message if an expression was expected but not read + */ static expression_t *expected_expression_error(void) { - errorf(HERE, "expected expression, got token '%K'", &token); - + /* skip the error message if the error token was read */ + if (token.type != T_ERROR) { + errorf(HERE, "expected expression, got token '%K'", &token); + } next_token(); return create_invalid_expression(); @@ -2985,8 +2965,7 @@ static declaration_t *create_implicit_function(symbol_t *symbol, free_type(ntype); } - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); - + declaration_t *const declaration = allocate_declaration_zero(); declaration->storage_class = STORAGE_CLASS_EXTERN; declaration->type = type; declaration->symbol = symbol; @@ -3063,9 +3042,6 @@ static type_t *get_builtin_symbol_type(symbol_t *symbol) */ static type_t *automatic_type_conversion(type_t *orig_type) { - if(orig_type == NULL) - return NULL; - type_t *type = skip_typeref(orig_type); if(is_type_array(type)) { array_type_t *array_type = &type->array; @@ -3088,42 +3064,30 @@ static type_t *automatic_type_conversion(type_t *orig_type) */ type_t *revert_automatic_type_conversion(const expression_t *expression) { - if(expression->base.datatype == NULL) - return NULL; + switch (expression->kind) { + case EXPR_REFERENCE: return expression->reference.declaration->type; + case EXPR_SELECT: return expression->select.compound_entry->type; - switch(expression->kind) { - case EXPR_REFERENCE: { - const reference_expression_t *ref = &expression->reference; - return ref->declaration->type; - } - case EXPR_SELECT: { - const select_expression_t *select = &expression->select; - return select->compound_entry->type; - } - case EXPR_UNARY_DEREFERENCE: { - expression_t *value = expression->unary.value; - type_t *type = skip_typeref(value->base.datatype); - pointer_type_t *pointer_type = &type->pointer; + case EXPR_UNARY_DEREFERENCE: { + const expression_t *const value = expression->unary.value; + type_t *const type = skip_typeref(value->base.datatype); + assert(is_type_pointer(type)); + return type->pointer.points_to; + } - return pointer_type->points_to; - } - case EXPR_BUILTIN_SYMBOL: { - const builtin_symbol_expression_t *builtin - = &expression->builtin_symbol; - return get_builtin_symbol_type(builtin->symbol); - } - case EXPR_ARRAY_ACCESS: { - const array_access_expression_t *array_access - = &expression->array_access; - const expression_t *array_ref = array_access->array_ref; - type_t *type_left = skip_typeref(array_ref->base.datatype); - assert(is_type_pointer(type_left)); - pointer_type_t *pointer_type = &type_left->pointer; - return pointer_type->points_to; - } + case EXPR_BUILTIN_SYMBOL: + return get_builtin_symbol_type(expression->builtin_symbol.symbol); - default: - break; + case EXPR_ARRAY_ACCESS: { + const expression_t *const array_ref = expression->array_access.array_ref; + type_t *const type_left = skip_typeref(array_ref->base.datatype); + if (!is_type_valid(type_left)) + return type_left; + assert(is_type_pointer(type_left)); + return type_left->pointer.points_to; + } + + default: break; } return expression->base.datatype; @@ -3144,8 +3108,10 @@ static expression_t *parse_reference(void) if(declaration == NULL) { if (! strict_mode && token.type == '(') { /* an implicitly defined function */ - warningf(HERE, "implicit declaration of function '%Y'", - ref->symbol); + if (warning.implicit_function_declaration) { + warningf(HERE, "implicit declaration of function '%Y'", + ref->symbol); + } declaration = create_implicit_function(ref->symbol, source_position); @@ -3197,31 +3163,24 @@ static expression_t *parse_statement_expression(void) { expression_t *expression = allocate_expression_zero(EXPR_STATEMENT); - statement_t *statement = parse_compound_statement(); - expression->statement.statement = statement; - if(statement == NULL) { - expect(')'); - return NULL; - } - - assert(statement->kind == STATEMENT_COMPOUND); - compound_statement_t *compound_statement = &statement->compound; + statement_t *statement = parse_compound_statement(); + expression->statement.statement = statement; + expression->base.source_position = statement->base.source_position; - /* find last statement and use it's type */ - const statement_t *last_statement = NULL; - const statement_t *iter = compound_statement->statements; - for( ; iter != NULL; iter = iter->base.next) { - last_statement = iter; - } + /* find last statement and use its type */ + type_t *type = type_void; + const statement_t *stmt = statement->compound.statements; + if (stmt != NULL) { + while (stmt->base.next != NULL) + stmt = stmt->base.next; - if(last_statement->kind == STATEMENT_EXPRESSION) { - const expression_statement_t *expression_statement - = &last_statement->expression; - expression->base.datatype - = expression_statement->expression->base.datatype; + if (stmt->kind == STATEMENT_EXPRESSION) { + type = stmt->expression.expression->base.datatype; + } } else { - expression->base.datatype = type_void; + warningf(expression->base.source_position, "empty statement expression ({})"); } + expression->base.datatype = type; expect(')'); @@ -3266,7 +3225,6 @@ static expression_t *parse_function_keyword(void) expression->expression.kind = EXPR_FUNCTION; expression->expression.datatype = type_string; - expression->value = current_function->symbol->string; return (expression_t*) expression; } @@ -3285,7 +3243,6 @@ static expression_t *parse_pretty_function_keyword(void) expression->expression.kind = EXPR_PRETTY_FUNCTION; expression->expression.datatype = type_string; - expression->value = current_function->symbol->string; return (expression_t*) expression; } @@ -3483,16 +3440,16 @@ static expression_t *parse_compare_builtin(void) expression->binary.right = parse_assignment_expression(); expect(')'); - type_t *orig_type_left = expression->binary.left->base.datatype; - type_t *orig_type_right = expression->binary.right->base.datatype; - if(orig_type_left == NULL || orig_type_right == NULL) - return expression; + type_t *const orig_type_left = expression->binary.left->base.datatype; + type_t *const orig_type_right = expression->binary.right->base.datatype; - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); if(!is_type_floating(type_left) && !is_type_floating(type_right)) { - type_error_incompatible("invalid operands in comparison", - token.source_position, type_left, type_right); + if (is_type_valid(type_left) && is_type_valid(type_right)) { + type_error_incompatible("invalid operands in comparison", + token.source_position, orig_type_left, orig_type_right); + } } else { semantic_comparison(&expression->binary); } @@ -3606,14 +3563,13 @@ static expression_t *parse_primary_expression(void) * Check if the expression has the character type and issue a warning then. */ static void check_for_char_index_type(const expression_t *expression) { - type_t *type = expression->base.datatype; - type_t *base_type = skip_typeref(type); + type_t *const type = expression->base.datatype; + const type_t *const base_type = skip_typeref(type); - if (base_type->base.kind == TYPE_ATOMIC) { - if (base_type->atomic.akind == ATOMIC_TYPE_CHAR) { - warningf(expression->base.source_position, - "array subscript has type '%T'", type); - } + if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) && + warning.char_subscripts) { + warningf(expression->base.source_position, + "array subscript has type '%T'", type); } } @@ -3631,33 +3587,32 @@ static expression_t *parse_array_expression(unsigned precedence, array_access->expression.kind = EXPR_ARRAY_ACCESS; - type_t *type_left = left->base.datatype; - type_t *type_inside = inside->base.datatype; - type_t *return_type = NULL; - - if(type_left != NULL && type_inside != NULL) { - type_left = skip_typeref(type_left); - type_inside = skip_typeref(type_inside); - - if(is_type_pointer(type_left)) { - pointer_type_t *pointer = &type_left->pointer; - return_type = pointer->points_to; - array_access->array_ref = left; - array_access->index = inside; - check_for_char_index_type(inside); - } else if(is_type_pointer(type_inside)) { - pointer_type_t *pointer = &type_inside->pointer; - return_type = pointer->points_to; - array_access->array_ref = inside; - array_access->index = left; - array_access->flipped = true; - check_for_char_index_type(left); - } else { - errorf(HERE, "array access on object with non-pointer types '%T', '%T'", type_left, type_inside); - } - } else { + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_inside = inside->base.datatype; + + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_inside = skip_typeref(orig_type_inside); + + type_t *return_type; + if (is_type_pointer(type_left)) { + return_type = type_left->pointer.points_to; array_access->array_ref = left; array_access->index = inside; + check_for_char_index_type(inside); + } else if (is_type_pointer(type_inside)) { + return_type = type_inside->pointer.points_to; + array_access->array_ref = inside; + array_access->index = left; + array_access->flipped = true; + check_for_char_index_type(left); + } else { + if (is_type_valid(type_left) && is_type_valid(type_inside)) { + errorf(HERE, + "array access on object with non-pointer types '%T', '%T'", + orig_type_left, orig_type_inside); + } + return_type = type_error_type; + array_access->array_ref = create_invalid_expression(); } if(token.type != ']') { @@ -3716,32 +3671,31 @@ static expression_t *parse_select_expression(unsigned precedence, select->select.symbol = symbol; next_token(); - type_t *orig_type = compound->base.datatype; - if(orig_type == NULL) - return create_invalid_expression(); - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = compound->base.datatype; + type_t *const type = skip_typeref(orig_type); type_t *type_left = type; if(is_pointer) { - if(type->kind != TYPE_POINTER) { - errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type); + if (!is_type_pointer(type)) { + if (is_type_valid(type)) { + errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type); + } return create_invalid_expression(); } - pointer_type_t *pointer_type = &type->pointer; - type_left = pointer_type->points_to; + type_left = type->pointer.points_to; } type_left = skip_typeref(type_left); - if(type_left->kind != TYPE_COMPOUND_STRUCT - && type_left->kind != TYPE_COMPOUND_UNION) { - errorf(HERE, "request for member '%Y' in something not a struct or " - "union, but '%T'", symbol, type_left); + if (type_left->kind != TYPE_COMPOUND_STRUCT && + type_left->kind != TYPE_COMPOUND_UNION) { + if (is_type_valid(type_left)) { + errorf(HERE, "request for member '%Y' in something not a struct or " + "union, but '%T'", symbol, type_left); + } return create_invalid_expression(); } - compound_type_t *compound_type = &type_left->compound; - declaration_t *declaration = compound_type->declaration; + declaration_t *const declaration = type_left->compound.declaration; if(!declaration->init.is_defined) { errorf(HERE, "request for member '%Y' of incomplete type '%T'", @@ -3793,27 +3747,21 @@ static expression_t *parse_call_expression(unsigned precedence, call_expression_t *call = &result->call; call->function = expression; - function_type_t *function_type = NULL; - type_t *orig_type = expression->base.datatype; - if(orig_type != NULL) { - type_t *type = skip_typeref(orig_type); - - if(is_type_pointer(type)) { - pointer_type_t *pointer_type = &type->pointer; + type_t *const orig_type = expression->base.datatype; + type_t *const type = skip_typeref(orig_type); - type = skip_typeref(pointer_type->points_to); + function_type_t *function_type = NULL; + if (is_type_pointer(type)) { + type_t *const to_type = skip_typeref(type->pointer.points_to); - if (is_type_function(type)) { - function_type = &type->function; - call->expression.datatype = function_type->return_type; - } + if (is_type_function(to_type)) { + function_type = &to_type->function; + call->expression.datatype = function_type->return_type; } - if(function_type == NULL) { - errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type); + } - function_type = NULL; - call->expression.datatype = NULL; - } + if (function_type == NULL && is_type_valid(type)) { + errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type); } /* parse arguments */ @@ -3847,8 +3795,16 @@ static expression_t *parse_call_expression(unsigned precedence, parameter = parameter->next, argument = argument->next) { type_t *expected_type = parameter->type; /* TODO report context in error messages */ - argument->expression = create_implicit_cast(argument->expression, - expected_type); + expression_t *const arg_expr = argument->expression; + type_t *const res_type = semantic_assign(expected_type, arg_expr, "function call"); + if (res_type == NULL) { + /* TODO improve error message */ + errorf(arg_expr->base.source_position, + "Cannot call function with argument '%E' of type '%T' where type '%T' is expected", + arg_expr, arg_expr->base.datatype, expected_type); + } else { + argument->expression = create_implicit_cast(argument->expression, expected_type); + } } /* too few parameters */ if(parameter != NULL) { @@ -3863,9 +3819,6 @@ static expression_t *parse_call_expression(unsigned precedence, for( ; argument != NULL; argument = argument->next) { type_t *type = argument->expression->base.datatype; - if(type == NULL) - continue; - type = skip_typeref(type); if(is_type_integer(type)) { type = promote_integer(type); @@ -3891,15 +3844,10 @@ static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right); static bool same_compound_type(const type_t *type1, const type_t *type2) { - if(!is_type_compound(type1)) - return false; - if(type1->kind != type2->kind) - return false; - - const compound_type_t *compound1 = &type1->compound; - const compound_type_t *compound2 = &type2->compound; - - return compound1->declaration == compound2->declaration; + return + is_type_compound(type1) && + type1->kind == type2->kind && + type1->compound.declaration == type2->compound.declaration; } /** @@ -3918,13 +3866,11 @@ static expression_t *parse_conditional_expression(unsigned precedence, conditional->condition = expression; /* 6.5.15.2 */ - type_t *condition_type_orig = expression->base.datatype; - if(condition_type_orig != NULL) { - type_t *condition_type = skip_typeref(condition_type_orig); - if(condition_type != NULL && !is_type_scalar(condition_type)) { - type_error("expected a scalar type in conditional condition", - expression->base.source_position, condition_type_orig); - } + type_t *const condition_type_orig = expression->base.datatype; + type_t *const condition_type = skip_typeref(condition_type_orig); + if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) { + type_error("expected a scalar type in conditional condition", + expression->base.source_position, condition_type_orig); } expression_t *true_expression = parse_expression(); @@ -3934,16 +3880,13 @@ static expression_t *parse_conditional_expression(unsigned precedence, conditional->true_expression = true_expression; conditional->false_expression = false_expression; - type_t *orig_true_type = true_expression->base.datatype; - type_t *orig_false_type = false_expression->base.datatype; - if(orig_true_type == NULL || orig_false_type == NULL) - return result; - - type_t *true_type = skip_typeref(orig_true_type); - type_t *false_type = skip_typeref(orig_false_type); + type_t *const orig_true_type = true_expression->base.datatype; + type_t *const orig_false_type = false_expression->base.datatype; + type_t *const true_type = skip_typeref(orig_true_type); + type_t *const false_type = skip_typeref(orig_false_type); /* 6.5.15.3 */ - type_t *result_type = NULL; + type_t *result_type; if (is_type_arithmetic(true_type) && is_type_arithmetic(false_type)) { result_type = semantic_arithmetic(true_type, false_type); @@ -3953,9 +3896,10 @@ static expression_t *parse_conditional_expression(unsigned precedence, conditional->true_expression = true_expression; conditional->false_expression = false_expression; conditional->expression.datatype = result_type; - } else if (same_compound_type(true_type, false_type) - || (is_type_atomic(true_type, ATOMIC_TYPE_VOID) && - is_type_atomic(false_type, ATOMIC_TYPE_VOID))) { + } else if (same_compound_type(true_type, false_type) || ( + is_type_atomic(true_type, ATOMIC_TYPE_VOID) && + is_type_atomic(false_type, ATOMIC_TYPE_VOID) + )) { /* just take 1 of the 2 types */ result_type = true_type; } else if (is_type_pointer(true_type) && is_type_pointer(false_type) @@ -3964,9 +3908,12 @@ static expression_t *parse_conditional_expression(unsigned precedence, result_type = true_type; } else { /* TODO */ - type_error_incompatible("while parsing conditional", - expression->base.source_position, true_type, - false_type); + if (is_type_valid(true_type) && is_type_valid(false_type)) { + type_error_incompatible("while parsing conditional", + expression->base.source_position, true_type, + false_type); + } + result_type = type_error_type; } conditional->expression.datatype = result_type; @@ -4003,14 +3950,14 @@ static expression_t *parse_builtin_classify_type(const unsigned precedence) static void semantic_incdec(unary_expression_t *expression) { - type_t *orig_type = expression->value->base.datatype; - if(orig_type == NULL) - return; - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = expression->value->base.datatype; + type_t *const type = skip_typeref(orig_type); + /* TODO !is_type_real && !is_type_pointer */ if(!is_type_arithmetic(type) && type->kind != TYPE_POINTER) { - /* TODO: improve error message */ - errorf(HERE, "operation needs an arithmetic or pointer type"); + if (is_type_valid(type)) { + /* TODO: improve error message */ + errorf(HERE, "operation needs an arithmetic or pointer type"); + } return; } @@ -4019,14 +3966,13 @@ static void semantic_incdec(unary_expression_t *expression) static void semantic_unexpr_arithmetic(unary_expression_t *expression) { - type_t *orig_type = expression->value->base.datatype; - if(orig_type == NULL) - return; - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = expression->value->base.datatype; + type_t *const type = skip_typeref(orig_type); if(!is_type_arithmetic(type)) { - /* TODO: improve error message */ - errorf(HERE, "operation needs an arithmetic type"); + if (is_type_valid(type)) { + /* TODO: improve error message */ + errorf(HERE, "operation needs an arithmetic type"); + } return; } @@ -4035,13 +3981,12 @@ static void semantic_unexpr_arithmetic(unary_expression_t *expression) static void semantic_unexpr_scalar(unary_expression_t *expression) { - type_t *orig_type = expression->value->base.datatype; - if(orig_type == NULL) - return; - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = expression->value->base.datatype; + type_t *const type = skip_typeref(orig_type); if (!is_type_scalar(type)) { - errorf(HERE, "operand of ! must be of scalar type"); + if (is_type_valid(type)) { + errorf(HERE, "operand of ! must be of scalar type"); + } return; } @@ -4050,13 +3995,12 @@ static void semantic_unexpr_scalar(unary_expression_t *expression) static void semantic_unexpr_integer(unary_expression_t *expression) { - type_t *orig_type = expression->value->base.datatype; - if(orig_type == NULL) - return; - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = expression->value->base.datatype; + type_t *const type = skip_typeref(orig_type); if (!is_type_integer(type)) { - errorf(HERE, "operand of ~ must be of integer type"); + if (is_type_valid(type)) { + errorf(HERE, "operand of ~ must be of integer type"); + } return; } @@ -4065,19 +4009,16 @@ static void semantic_unexpr_integer(unary_expression_t *expression) static void semantic_dereference(unary_expression_t *expression) { - type_t *orig_type = expression->value->base.datatype; - if(orig_type == NULL) - return; - - type_t *type = skip_typeref(orig_type); + type_t *const orig_type = expression->value->base.datatype; + type_t *const type = skip_typeref(orig_type); if(!is_type_pointer(type)) { - errorf(HERE, "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type); + if (is_type_valid(type)) { + errorf(HERE, "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type); + } return; } - pointer_type_t *pointer_type = &type->pointer; - type_t *result_type = pointer_type->points_to; - + type_t *result_type = type->pointer.points_to; result_type = automatic_type_conversion(result_type); expression->expression.datatype = result_type; } @@ -4091,12 +4032,11 @@ static void semantic_take_addr(unary_expression_t *expression) value->base.datatype = revert_automatic_type_conversion(value); type_t *orig_type = value->base.datatype; - if(orig_type == NULL) + if(!is_type_valid(orig_type)) return; if(value->kind == EXPR_REFERENCE) { - reference_expression_t *reference = (reference_expression_t*) value; - declaration_t *declaration = reference->declaration; + declaration_t *const declaration = value->reference.declaration; if(declaration != NULL) { if (declaration->storage_class == STORAGE_CLASS_REGISTER) { errorf(expression->expression.source_position, @@ -4209,20 +4149,18 @@ static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right) */ static void semantic_binexpr_arithmetic(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) { /* TODO: improve error message */ - errorf(HERE, "operation needs arithmetic types"); + if (is_type_valid(type_left) && is_type_valid(type_right)) { + errorf(HERE, "operation needs arithmetic types"); + } return; } @@ -4234,20 +4172,18 @@ static void semantic_binexpr_arithmetic(binary_expression_t *expression) static void semantic_shift_op(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t * type_left = skip_typeref(orig_type_left); + type_t * type_right = skip_typeref(orig_type_right); if(!is_type_integer(type_left) || !is_type_integer(type_right)) { /* TODO: improve error message */ - errorf(HERE, "operation needs integer types"); + if (is_type_valid(type_left) && is_type_valid(type_right)) { + errorf(HERE, "operation needs integer types"); + } return; } @@ -4261,16 +4197,12 @@ static void semantic_shift_op(binary_expression_t *expression) static void semantic_add(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); /* § 5.6.5 */ if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) { @@ -4283,23 +4215,19 @@ static void semantic_add(binary_expression_t *expression) expression->expression.datatype = type_left; } else if(is_type_pointer(type_right) && is_type_integer(type_left)) { expression->expression.datatype = type_right; - } else { + } else if (is_type_valid(type_left) && is_type_valid(type_right)) { errorf(HERE, "invalid operands to binary + ('%T', '%T')", orig_type_left, orig_type_right); } } static void semantic_sub(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); /* § 5.6.5 */ if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) { @@ -4312,12 +4240,12 @@ static void semantic_sub(binary_expression_t *expression) expression->expression.datatype = type_left; } else if(is_type_pointer(type_left) && is_type_pointer(type_right)) { if(!pointers_compatible(type_left, type_right)) { - errorf(HERE, "pointers to incompatible objects to binary - ('%T', '%T')", orig_type_left, orig_type_right); + errorf(HERE, "pointers to incompatible objects to binary '-' ('%T', '%T')", orig_type_left, orig_type_right); } else { expression->expression.datatype = type_ptrdiff_t; } - } else { - errorf(HERE, "invalid operands to binary - ('%T', '%T')", orig_type_left, orig_type_right); + } else if (is_type_valid(type_left) && is_type_valid(type_right)) { + errorf(HERE, "invalid operands to binary '-' ('%T', '%T')", orig_type_left, orig_type_right); } } @@ -4328,9 +4256,6 @@ static void semantic_comparison(binary_expression_t *expression) type_t *orig_type_left = left->base.datatype; type_t *orig_type_right = right->base.datatype; - if(orig_type_left == NULL || orig_type_right == NULL) - return; - type_t *type_left = skip_typeref(orig_type_left); type_t *type_right = skip_typeref(orig_type_right); @@ -4346,7 +4271,7 @@ static void semantic_comparison(binary_expression_t *expression) expression->right = create_implicit_cast(right, type_left); } else if (is_type_pointer(type_right)) { expression->left = create_implicit_cast(left, type_right); - } else { + } else if (is_type_valid(type_left) && is_type_valid(type_right)) { type_error_incompatible("invalid operands in comparison", token.source_position, type_left, type_right); } @@ -4360,15 +4285,14 @@ static void semantic_arithmetic_assign(binary_expression_t *expression) type_t *orig_type_left = left->base.datatype; type_t *orig_type_right = right->base.datatype; - if(orig_type_left == NULL || orig_type_right == NULL) - return; - type_t *type_left = skip_typeref(orig_type_left); type_t *type_right = skip_typeref(orig_type_right); if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) { /* TODO: improve error message */ - errorf(HERE, "operation needs arithmetic types"); + if (is_type_valid(type_left) && is_type_valid(type_right)) { + errorf(HERE, "operation needs arithmetic types"); + } return; } @@ -4383,16 +4307,12 @@ static void semantic_arithmetic_assign(binary_expression_t *expression) static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) { /* combined instructions are tricky. We can't create an implicit cast on @@ -4404,9 +4324,8 @@ static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression) expression->expression.datatype = type_left; } else if (is_type_pointer(type_left) && is_type_integer(type_right)) { expression->expression.datatype = type_left; - } else { + } else if (is_type_valid(type_left) && is_type_valid(type_right)) { errorf(HERE, "incompatible types '%T' and '%T' in assignment", orig_type_left, orig_type_right); - return; } } @@ -4415,20 +4334,18 @@ static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression) */ static void semantic_logical_op(binary_expression_t *expression) { - expression_t *left = expression->left; - expression_t *right = expression->right; - type_t *orig_type_left = left->base.datatype; - type_t *orig_type_right = right->base.datatype; - - if(orig_type_left == NULL || orig_type_right == NULL) - return; - - type_t *type_left = skip_typeref(orig_type_left); - type_t *type_right = skip_typeref(orig_type_right); + expression_t *const left = expression->left; + expression_t *const right = expression->right; + type_t *const orig_type_left = left->base.datatype; + type_t *const orig_type_right = right->base.datatype; + type_t *const type_left = skip_typeref(orig_type_left); + type_t *const type_right = skip_typeref(orig_type_right); if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) { /* TODO: improve error message */ - errorf(HERE, "operation needs scalar types"); + if (is_type_valid(type_left) && is_type_valid(type_right)) { + errorf(HERE, "operation needs scalar types"); + } return; } @@ -4463,9 +4380,6 @@ static void semantic_binexpr_assign(binary_expression_t *expression) expression_t *left = expression->left; type_t *orig_type_left = left->base.datatype; - if(orig_type_left == NULL) - return; - type_t *type_left = revert_automatic_type_conversion(left); type_left = skip_typeref(orig_type_left); @@ -4491,13 +4405,128 @@ static void semantic_binexpr_assign(binary_expression_t *expression) return; } - semantic_assign(orig_type_left, &expression->right, "assignment"); + type_t *const res_type = semantic_assign(orig_type_left, expression->right, + "assignment"); + if (res_type == NULL) { + errorf(expression->expression.source_position, + "cannot assign to '%T' from '%T'", + orig_type_left, expression->right->base.datatype); + } else { + expression->right = create_implicit_cast(expression->right, res_type); + } expression->expression.datatype = orig_type_left; } +static bool expression_has_effect(const expression_t *const expr) +{ + switch (expr->kind) { + case EXPR_UNKNOWN: break; + case EXPR_INVALID: break; + case EXPR_REFERENCE: return false; + case EXPR_CONST: return false; + case EXPR_STRING_LITERAL: return false; + case EXPR_WIDE_STRING_LITERAL: return false; + case EXPR_CALL: { + const call_expression_t *const call = &expr->call; + if (call->function->kind != EXPR_BUILTIN_SYMBOL) + return true; + + switch (call->function->builtin_symbol.symbol->ID) { + case T___builtin_va_end: return true; + default: return false; + } + } + case EXPR_CONDITIONAL: { + const conditional_expression_t *const cond = &expr->conditional; + return + expression_has_effect(cond->true_expression) && + expression_has_effect(cond->false_expression); + } + case EXPR_SELECT: return false; + case EXPR_ARRAY_ACCESS: return false; + case EXPR_SIZEOF: return false; + case EXPR_CLASSIFY_TYPE: return false; + case EXPR_ALIGNOF: return false; + + case EXPR_FUNCTION: return false; + case EXPR_PRETTY_FUNCTION: return false; + case EXPR_BUILTIN_SYMBOL: break; /* handled in EXPR_CALL */ + case EXPR_BUILTIN_CONSTANT_P: return false; + case EXPR_BUILTIN_PREFETCH: return true; + case EXPR_OFFSETOF: return false; + case EXPR_VA_START: return true; + case EXPR_VA_ARG: return true; + case EXPR_STATEMENT: return true; // TODO + + case EXPR_UNARY_NEGATE: return false; + case EXPR_UNARY_PLUS: return false; + case EXPR_UNARY_BITWISE_NEGATE: return false; + case EXPR_UNARY_NOT: return false; + case EXPR_UNARY_DEREFERENCE: return false; + case EXPR_UNARY_TAKE_ADDRESS: return false; + case EXPR_UNARY_POSTFIX_INCREMENT: return true; + case EXPR_UNARY_POSTFIX_DECREMENT: return true; + case EXPR_UNARY_PREFIX_INCREMENT: return true; + case EXPR_UNARY_PREFIX_DECREMENT: return true; + case EXPR_UNARY_CAST: + return is_type_atomic(expr->base.datatype, ATOMIC_TYPE_VOID); + case EXPR_UNARY_CAST_IMPLICIT: return true; + case EXPR_UNARY_ASSUME: return true; + case EXPR_UNARY_BITFIELD_EXTRACT: return false; + + case EXPR_BINARY_ADD: return false; + case EXPR_BINARY_SUB: return false; + case EXPR_BINARY_MUL: return false; + case EXPR_BINARY_DIV: return false; + case EXPR_BINARY_MOD: return false; + case EXPR_BINARY_EQUAL: return false; + case EXPR_BINARY_NOTEQUAL: return false; + case EXPR_BINARY_LESS: return false; + case EXPR_BINARY_LESSEQUAL: return false; + case EXPR_BINARY_GREATER: return false; + case EXPR_BINARY_GREATEREQUAL: return false; + case EXPR_BINARY_BITWISE_AND: return false; + case EXPR_BINARY_BITWISE_OR: return false; + case EXPR_BINARY_BITWISE_XOR: return false; + case EXPR_BINARY_SHIFTLEFT: return false; + case EXPR_BINARY_SHIFTRIGHT: return false; + case EXPR_BINARY_ASSIGN: return true; + case EXPR_BINARY_MUL_ASSIGN: return true; + case EXPR_BINARY_DIV_ASSIGN: return true; + case EXPR_BINARY_MOD_ASSIGN: return true; + case EXPR_BINARY_ADD_ASSIGN: return true; + case EXPR_BINARY_SUB_ASSIGN: return true; + case EXPR_BINARY_SHIFTLEFT_ASSIGN: return true; + case EXPR_BINARY_SHIFTRIGHT_ASSIGN: return true; + case EXPR_BINARY_BITWISE_AND_ASSIGN: return true; + case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true; + case EXPR_BINARY_BITWISE_OR_ASSIGN: return true; + case EXPR_BINARY_LOGICAL_AND: + case EXPR_BINARY_LOGICAL_OR: + case EXPR_BINARY_COMMA: + return expression_has_effect(expr->binary.right); + + case EXPR_BINARY_BUILTIN_EXPECT: return true; + case EXPR_BINARY_ISGREATER: return false; + case EXPR_BINARY_ISGREATEREQUAL: return false; + case EXPR_BINARY_ISLESS: return false; + case EXPR_BINARY_ISLESSEQUAL: return false; + case EXPR_BINARY_ISLESSGREATER: return false; + case EXPR_BINARY_ISUNORDERED: return false; + } + + panic("unexpected statement"); +} + static void semantic_comma(binary_expression_t *expression) { + if (warning.unused_value) { + const expression_t *const left = expression->left; + if (!expression_has_effect(left)) { + warningf(left->base.source_position, "left-hand operand of comma expression has no effect"); + } + } expression->expression.datatype = expression->right->base.datatype; } @@ -4858,23 +4887,44 @@ static statement_t *parse_case_statement(void) expect(':'); - if (current_switch != NULL) { - /* link all cases into the switch statement */ - if (current_switch->last_case == NULL) { - current_switch->first_case = - current_switch->last_case = &statement->case_label; + if (! is_constant_expression(statement->case_label.expression)) { + errorf(statement->base.source_position, + "case label does not reduce to an integer constant"); + } else { + /* TODO: check if the case label is already known */ + if (current_switch != NULL) { + /* link all cases into the switch statement */ + if (current_switch->last_case == NULL) { + current_switch->first_case = + current_switch->last_case = &statement->case_label; + } else { + current_switch->last_case->next = &statement->case_label; + } } else { - current_switch->last_case->next = &statement->case_label; + errorf(statement->base.source_position, + "case label not within a switch statement"); } - } else { - errorf(statement->base.source_position, - "case label not within a switch statement"); } statement->case_label.label_statement = parse_statement(); return statement; } +/** + * Finds an existing default label of a switch statement. + */ +static case_label_statement_t * +find_default_label(const switch_statement_t *statement) +{ + for (case_label_statement_t *label = statement->first_case; + label != NULL; + label = label->next) { + if (label->expression == NULL) + return label; + } + return NULL; +} + /** * Parse a default statement. */ @@ -4888,12 +4938,19 @@ static statement_t *parse_default_statement(void) expect(':'); if (current_switch != NULL) { - /* link all cases into the switch statement */ - if (current_switch->last_case == NULL) { - current_switch->first_case = - current_switch->last_case = &statement->case_label; + const case_label_statement_t *def_label = find_default_label(current_switch); + if (def_label != NULL) { + errorf(HERE, "multiple default labels in one switch"); + errorf(def_label->statement.source_position, + "this is the first default label"); } else { - current_switch->last_case->next = &statement->case_label; + /* link all cases into the switch statement */ + if (current_switch->last_case == NULL) { + current_switch->first_case = + current_switch->last_case = &statement->case_label; + } else { + current_switch->last_case->next = &statement->case_label; + } } } else { errorf(statement->base.source_position, @@ -4919,7 +4976,7 @@ static declaration_t *get_label(symbol_t *symbol) } /* otherwise we need to create a new one */ - declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0])); + declaration_t *const declaration = allocate_declaration_zero(); declaration->namespc = NAMESPACE_LABEL; declaration->symbol = symbol; @@ -5005,7 +5062,13 @@ static statement_t *parse_switch(void) expect('('); expression_t *const expr = parse_expression(); - type_t *const type = promote_integer(skip_typeref(expr->base.datatype)); + type_t * type = skip_typeref(expr->base.datatype); + if (is_type_integer(type)) { + type = promote_integer(type); + } else if (is_type_valid(type)) { + errorf(expr->base.source_position, "switch quantity is not an integer, but '%T'", type); + type = type_error_type; + } statement->expression = create_implicit_cast(expr, type); expect(')'); @@ -5014,9 +5077,22 @@ static statement_t *parse_switch(void) statement->body = parse_statement(); current_switch = rem; + if (warning.switch_default && find_default_label(statement) == NULL) { + warningf(statement->statement.source_position, "switch has no default case"); + } + return (statement_t*) statement; } +static statement_t *parse_loop_body(statement_t *const loop) +{ + statement_t *const rem = current_loop; + current_loop = loop; + statement_t *const body = parse_statement(); + current_loop = rem; + return body; +} + /** * Parse a while statement. */ @@ -5028,18 +5104,13 @@ static statement_t *parse_while(void) statement->statement.kind = STATEMENT_WHILE; statement->statement.source_position = token.source_position; - statement_t *rem = current_loop; - expect_fail('('); + expect('('); statement->condition = parse_expression(); - expect_fail(')'); + expect(')'); - statement->body = parse_statement(); - current_loop = rem; + statement->body = parse_loop_body((statement_t*)statement); return (statement_t*) statement; -fail: - current_loop = rem; - return NULL; } /** @@ -5053,19 +5124,14 @@ static statement_t *parse_do(void) statement->statement.kind = STATEMENT_DO_WHILE; statement->statement.source_position = token.source_position; - statement_t *rem = current_loop; - statement->body = parse_statement(); - expect_fail(T_while); - expect_fail('('); + statement->body = parse_loop_body((statement_t*)statement); + expect(T_while); + expect('('); statement->condition = parse_expression(); - expect_fail(')'); - current_loop = rem; + expect(')'); expect(';'); return (statement_t*) statement; -fail: - current_loop = rem; - return NULL; } /** @@ -5081,7 +5147,6 @@ static statement_t *parse_for(void) expect('('); - statement_t *rem = current_loop; int top = environment_top(); context_t *last_context = context; set_context(&statement->context); @@ -5091,31 +5156,27 @@ static statement_t *parse_for(void) parse_declaration(record_declaration); } else { statement->initialisation = parse_expression(); - expect_fail(';'); + expect(';'); } } else { - expect_fail(';'); + expect(';'); } if(token.type != ';') { statement->condition = parse_expression(); } - expect_fail(';'); + expect(';'); if(token.type != ')') { statement->step = parse_expression(); } - expect_fail(')'); - statement->body = parse_statement(); + expect(')'); + statement->body = parse_loop_body((statement_t*)statement); assert(context == &statement->context); set_context(last_context); environment_pop_to(top); - current_loop = rem; return (statement_t*) statement; -fail: - current_loop = rem; - return NULL; } /** @@ -5142,6 +5203,13 @@ static statement_t *parse_goto(void) statement->label = label; + /* remember the goto's in a list for later checking */ + if (goto_last == NULL) { + goto_first = goto_last = statement; + } else { + goto_last->next = statement; + } + expect(';'); return (statement_t*) statement; @@ -5152,18 +5220,19 @@ static statement_t *parse_goto(void) */ static statement_t *parse_continue(void) { - eat(T_continue); - expect(';'); - - statement_t *statement = allocate_ast_zero(sizeof(statement[0])); - statement->kind = STATEMENT_CONTINUE; - statement->base.source_position = token.source_position; - + statement_t *statement; if (current_loop == NULL) { errorf(HERE, "continue statement not within loop"); - return NULL; + statement = NULL; + } else { + statement = allocate_statement_zero(STATEMENT_CONTINUE); + + statement->base.source_position = token.source_position; } + eat(T_continue); + expect(';'); + return statement; } @@ -5172,17 +5241,19 @@ static statement_t *parse_continue(void) */ static statement_t *parse_break(void) { - eat(T_break); - expect(';'); - - statement_t *statement = allocate_ast_zero(sizeof(statement[0])); - statement->kind = STATEMENT_BREAK; - statement->base.source_position = token.source_position; - + statement_t *statement; if (current_switch == NULL && current_loop == NULL) { errorf(HERE, "break statement not within loop or switch"); - return NULL; + statement = NULL; + } else { + statement = allocate_statement_zero(STATEMENT_BREAK); + + statement->base.source_position = token.source_position; } + + eat(T_break); + expect(';'); + return statement; } @@ -5230,22 +5301,15 @@ static statement_t *parse_return(void) statement->statement.kind = STATEMENT_RETURN; statement->statement.source_position = token.source_position; - assert(is_type_function(current_function->type)); - function_type_t *function_type = ¤t_function->type->function; - type_t *return_type = function_type->return_type; - expression_t *return_value = NULL; if(token.type != ';') { return_value = parse_expression(); } expect(';'); - if(return_type == NULL) - return (statement_t*) statement; - if(return_value != NULL && return_value->base.datatype == NULL) - return (statement_t*) statement; - - return_type = skip_typeref(return_type); + const type_t *const func_type = current_function->type; + assert(is_type_function(func_type)); + type_t *const return_type = skip_typeref(func_type->function.return_type); if(return_value != NULL) { type_t *return_value_type = skip_typeref(return_value->base.datatype); @@ -5256,8 +5320,14 @@ static statement_t *parse_return(void) "'return' with a value, in function returning void"); return_value = NULL; } else { - if(return_type != NULL) { - semantic_assign(return_type, &return_value, "'return'"); + type_t *const res_type = semantic_assign(return_type, + return_value, "'return'"); + if (res_type == NULL) { + errorf(statement->statement.source_position, + "cannot return something of type '%T' in function returning '%T'", + return_value->base.datatype, return_type); + } else { + return_value = create_implicit_cast(return_value, res_type); } } /* check for returning address of a local var */ @@ -5309,7 +5379,12 @@ static statement_t *parse_expression_statement(void) statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION); statement->base.source_position = token.source_position; - statement->expression.expression = parse_expression(); + expression_t *const expr = parse_expression(); + statement->expression.expression = expr; + + if (warning.unused_value && !expression_has_effect(expr)) { + warningf(expr->base.source_position, "statement has no effect"); + } expect(';'); @@ -5378,6 +5453,9 @@ static statement_t *parse_statement(void) break; case ';': + if (warning.empty_statement) { + warningf(HERE, "statement is empty"); + } next_token(); statement = NULL; break; @@ -5425,7 +5503,7 @@ static statement_t *parse_statement(void) */ static statement_t *parse_compound_statement(void) { - compound_statement_t *compound_statement + compound_statement_t *const compound_statement = allocate_ast_zero(sizeof(compound_statement[0])); compound_statement->statement.kind = STATEMENT_COMPOUND; compound_statement->statement.source_position = token.source_position;