fix uninitialized variable breaking implicitely defined functions
[cparser] / parser.c
index 31d692b..e042b89 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -2,6 +2,7 @@
 
 #include <assert.h>
 #include <stdarg.h>
+#include <stdbool.h>
 
 #include "parser.h"
 #include "lexer.h"
 //#define PRINT_TOKENS
 //#define ABORT_ON_ERROR
 #define MAX_LOOKAHEAD 2
+//#define STRICT_C99
 
-struct environment_entry_t {
-       symbol_t      *symbol;
+typedef struct {
        declaration_t *old_declaration;
-       const void    *old_context;
-};
+       symbol_t      *symbol;
+       unsigned short namespace;
+} stack_entry_t;
+
+static token_t         token;
+static token_t         lookahead_buffer[MAX_LOOKAHEAD];
+static int             lookahead_bufpos;
+static stack_entry_t  *environment_stack = NULL;
+static context_t      *global_context    = NULL;
+static context_t      *context           = NULL;
+static declaration_t  *last_declaration  = NULL;
+static declaration_t  *current_function  = NULL;
+static struct obstack  temp_obst;
+static bool            found_error;
+
+static type_t         *type_int         = NULL;
+static type_t         *type_uint        = NULL;
+static type_t         *type_long_double = NULL;
+static type_t         *type_double      = NULL;
+static type_t         *type_float       = NULL;
+static type_t         *type_const_char  = NULL;
+static type_t         *type_string      = NULL;
+static type_t         *type_void        = NULL;
+static type_t         *type_size_t      = NULL;
+static type_t         *type_ptrdiff_t   = NULL;
+
+static statement_t *parse_compound_statement(void);
+static statement_t *parse_statement(void);
+
+static expression_t *parse_sub_expression(unsigned precedence);
+static expression_t *parse_expression(void);
+static type_t       *parse_typename(void);
+
+#define STORAGE_CLASSES     \
+       case T_typedef:         \
+       case T_extern:          \
+       case T_static:          \
+       case T_auto:            \
+       case T_register:
+
+#define TYPE_QUALIFIERS     \
+       case T_const:           \
+       case T_restrict:        \
+       case T_volatile:        \
+       case T_inline:
 
-static token_t               token;
-static token_t               lookahead_buffer[MAX_LOOKAHEAD];
-static int                   lookahead_bufpos;
-static struct obstack        environment_obstack;
-static environment_entry_t **environment_stack = NULL;
-static context_t            *context           = NULL;
-static declaration_t        *last_declaration  = NULL;
-static struct obstack        temp_obst;
+#ifdef PROVIDE_COMPLEX
+#define COMPLEX_SPECIFIERS  \
+       case T__Complex:
+#else
+#define COMPLEX_SPECIFIERS
+#endif
+
+#ifdef PROVIDE_IMAGINARY
+#define IMAGINARY_SPECIFIERS \
+       case T__Imaginary:
+#else
+#define IMAGINARY_SPECIFIERS
+#endif
+
+#define TYPE_SPECIFIERS     \
+       case T_void:            \
+       case T_char:            \
+       case T_short:           \
+       case T_int:             \
+       case T_long:            \
+       case T_float:           \
+       case T_double:          \
+       case T_signed:          \
+       case T_unsigned:        \
+       case T__Bool:           \
+       case T_struct:          \
+       case T_union:           \
+       case T_enum:            \
+       case T___typeof__:      \
+       COMPLEX_SPECIFIERS      \
+       IMAGINARY_SPECIFIERS
 
-static
-statement_t *parse_compound_statement(void);
-static
-statement_t *parse_statement(void);
+#define DECLARATION_START   \
+       STORAGE_CLASSES         \
+       TYPE_QUALIFIERS         \
+       TYPE_SPECIFIERS
 
-static
-expression_t *parse_sub_expression(unsigned precedence);
-static
-expression_t *parse_expression(void);
+#define TYPENAME_START      \
+       TYPE_QUALIFIERS         \
+       TYPE_SPECIFIERS
 
-static inline
-void *allocate_ast_zero(size_t size)
+static inline void *allocate_ast_zero(size_t size)
 {
        void *res = allocate_ast(size);
        memset(res, 0, size);
        return res;
 }
 
-static inline
-void *allocate_type_zero(size_t size)
+static inline void *allocate_type_zero(size_t size)
 {
        void *res = obstack_alloc(type_obst, size);
        memset(res, 0, size);
        return res;
 }
 
+static inline void free_type(void *type)
+{
+       obstack_free(type_obst, type);
+}
+
 /**
  * returns the top element of the environment stack
  */
-static inline
-size_t environment_top(void)
+static inline size_t environment_top(void)
 {
        return ARR_LEN(environment_stack);
 }
 
 
 
-static inline
-void next_token(void)
+static inline void next_token(void)
 {
        token                              = lookahead_buffer[lookahead_bufpos];
        lookahead_buffer[lookahead_bufpos] = lexer_token;
@@ -84,46 +151,57 @@ void next_token(void)
 #endif
 }
 
-static inline
-const token_t *look_ahead(int num)
+static inline const token_t *look_ahead(int num)
 {
        assert(num > 0 && num <= MAX_LOOKAHEAD);
        int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
        return & lookahead_buffer[pos];
 }
 
-static inline
-void eat(token_type_t type)
+#define eat(token_type)  do { assert(token.type == token_type); next_token(); } while(0)
+
+static void error(void)
 {
-       assert(token.type == type);
-       next_token();
+       found_error = true;
+#ifdef ABORT_ON_ERROR
+       abort();
+#endif
 }
 
-void parser_print_error_prefix_pos(const source_position_t source_position)
+static void parser_print_prefix_pos(const source_position_t source_position)
 {
     fputs(source_position.input_name, stderr);
     fputc(':', stderr);
     fprintf(stderr, "%d", source_position.linenr);
-    fputs(": error: ", stderr);
-#ifdef ABORT_ON_ERROR
-       abort();
-#endif
+    fputs(": ", stderr);
+}
+
+static void parser_print_error_prefix_pos(
+               const source_position_t source_position)
+{
+       parser_print_prefix_pos(source_position);
+       fputs("error: ", stderr);
+       error();
 }
 
-void parser_print_error_prefix(void)
+static void parser_print_error_prefix(void)
 {
        parser_print_error_prefix_pos(token.source_position);
 }
 
-static
-void parse_error(const char *message)
+static void parse_error(const char *message)
 {
        parser_print_error_prefix();
        fprintf(stderr, "parse error: %s\n", message);
 }
 
-static
-void parse_error_expected(const char *message, ...)
+static void parse_warning(const char *message)
+{
+       parser_print_prefix_pos(token.source_position);
+       fprintf(stderr, "warning: %s\n", message);
+}
+
+static void parse_error_expected(const char *message, ...)
 {
        va_list args;
        int first = 1;
@@ -152,6 +230,28 @@ void parse_error_expected(const char *message, ...)
        fprintf(stderr, "\n");
 }
 
+static void type_error(const char *msg, const source_position_t source_position,
+                       type_t *type)
+{
+       parser_print_error_prefix_pos(source_position);
+       fprintf(stderr, "%s, but found type ", msg);
+       print_type(type);
+       fputc('\n', stderr);
+       error();
+}
+
+static void type_error_incompatible(const char *msg,
+               const source_position_t source_position, type_t *type1, type_t *type2)
+{
+       parser_print_error_prefix_pos(source_position);
+       fprintf(stderr, "%s, incompatible types: ", msg);
+       print_type(type1);
+       fprintf(stderr, " - ");
+       print_type(type2);
+       fprintf(stderr, ")\n");
+       error();
+}
+
 static void eat_block(void)
 {
        if(token.type == '{')
@@ -193,6 +293,13 @@ static void eat_brace(void)
        while(token.type != ')') {
                if(token.type == T_EOF)
                        return;
+               if(token.type == ')' || token.type == ';' || token.type == '}') {
+                       return;
+               }
+               if(token.type == '(') {
+                       eat_brace();
+                       continue;
+               }
                if(token.type == '{') {
                        eat_block();
                        continue;
@@ -222,126 +329,283 @@ static void set_context(context_t *new_context)
 {
        context = new_context;
 
-       declaration_t *declaration = new_context->declarations;
-       if(declaration != NULL) {
-               while(1) {
-                       if(declaration->next == NULL)
-                               break;
-                       declaration = declaration->next;
+       last_declaration = new_context->declarations;
+       if(last_declaration != NULL) {
+               while(last_declaration->next != NULL) {
+                       last_declaration = last_declaration->next;
                }
        }
-
-       last_declaration = declaration;
 }
 
 /**
  * called when we find a 2nd declarator for an identifier we already have a
  * declarator for
  */
-static int is_compatible_declaration (declaration_t *declaration,
+static bool is_compatible_declaration (declaration_t *declaration,
                                       declaration_t *previous)
 {
        /* TODO: not correct yet */
        return declaration->type == previous->type;
 }
 
+static declaration_t *get_declaration(symbol_t *symbol, namespace_t namespace)
+{
+       declaration_t *declaration = symbol->declaration;
+       for( ; declaration != NULL; declaration = declaration->symbol_next) {
+               if(declaration->namespace == namespace)
+                       return declaration;
+       }
+
+       return NULL;
+}
+
+static const char *get_namespace_prefix(namespace_t namespace)
+{
+       switch(namespace) {
+       case NAMESPACE_NORMAL:
+               return "";
+       case NAMESPACE_UNION:
+               return "union ";
+       case NAMESPACE_STRUCT:
+               return "struct ";
+       case NAMESPACE_ENUM:
+               return "enum ";
+       }
+       panic("invalid namespace found");
+}
+
 /**
  * pushs an environment_entry on the environment stack and links the
  * corresponding symbol to the new entry
  */
-static inline
-declaration_t *environment_push(declaration_t *declaration, const void *context)
+static declaration_t *environment_push(declaration_t *declaration)
 {
-       environment_entry_t *entry
-               = obstack_alloc(&environment_obstack, sizeof(entry[0]));
-       memset(entry, 0, sizeof(entry[0]));
+       symbol_t    *symbol    = declaration->symbol;
+       namespace_t  namespace = declaration->namespace;
+       assert(declaration->source_position.input_name != NULL);
 
-       int top = ARR_LEN(environment_stack);
-       ARR_RESIZE(environment_stack, top + 1);
-       environment_stack[top] = entry;
+       /* a declaration should be only pushed once */
+       assert(declaration->parent_context == NULL);
+       declaration->parent_context = context;
+
+       declaration_t *previous_declaration = get_declaration(symbol, namespace);
+       assert(declaration != previous_declaration);
+       if(previous_declaration != NULL
+                       && previous_declaration->parent_context == context) {
+               if(!is_compatible_declaration(declaration, previous_declaration)) {
+                       parser_print_error_prefix_pos(declaration->source_position);
+                       fprintf(stderr, "definition of symbol %s%s with type ",
+                                       get_namespace_prefix(namespace), symbol->string);
+                       error();
+                       print_type(declaration->type);
+                       fputc('\n', stderr);
+                       parser_print_error_prefix_pos(
+                                       previous_declaration->source_position);
+                       fprintf(stderr, "is incompatible with previous declaration "
+                                       "of type ");
+                       print_type(previous_declaration->type);
+                       fputc('\n', stderr);
+               }
+               return previous_declaration;
+       }
 
-       assert(declaration->source_position.input_name != NULL);
+       /* remember old declaration */
+       stack_entry_t entry;
+       entry.symbol          = symbol;
+       entry.old_declaration = symbol->declaration;
+       entry.namespace       = namespace;
+       ARR_APP1(environment_stack, entry);
 
-       symbol_t *symbol = declaration->symbol;
-       assert(declaration != symbol->declaration);
-
-       if(symbol->context == context) {
-               declaration_t *previous_declaration = symbol->declaration;
-               if(symbol->declaration != NULL) {
-                       if(!is_compatible_declaration(declaration, previous_declaration)) {
-                               parser_print_error_prefix_pos(declaration->source_position);
-                               fprintf(stderr, "definition of symbol '%s' with type ",
-                                       declaration->symbol->string);
-                               print_type(declaration->type, NULL);
-                               fputc('\n', stderr);
-                               parser_print_error_prefix_pos(
-                                               previous_declaration->source_position);
-                               fprintf(stderr, "is incompatible with previous declaration "
-                                       "of type ");
-                               print_type(previous_declaration->type, NULL);
-                               fputc('\n', stderr);
+       /* replace/add declaration into declaration list of the symbol */
+       if(symbol->declaration == NULL) {
+               symbol->declaration = declaration;
+       } else {
+               declaration_t *iter = symbol->declaration;
+               for( ; iter != NULL; iter = iter->symbol_next) {
+                       declaration_t *symbol_next = iter->symbol_next;
+                       if(symbol_next == NULL) {
+                               iter->symbol_next = declaration;
+                               assert(declaration->symbol_next == NULL);
+                               break;
+                       }
+                       if(symbol_next->namespace == namespace) {
+                               iter->symbol_next        = declaration;
+                               declaration->symbol_next = symbol_next->symbol_next;
+                               break;
                        }
-                       return previous_declaration;
                }
        }
 
-       entry->old_declaration = symbol->declaration;
-       entry->old_context     = symbol->context;
-       entry->symbol          = symbol;
-       symbol->declaration    = declaration;
-       symbol->context        = context;
-
        return declaration;
 }
 
 /**
  * pops symbols from the environment stack until @p new_top is the top element
  */
-static inline
-void environment_pop_to(size_t new_top)
+static void environment_pop_to(size_t new_top)
 {
-       environment_entry_t *entry = NULL;
        size_t top = ARR_LEN(environment_stack);
        size_t i;
 
+       assert(new_top <= top);
        if(new_top == top)
                return;
 
-       assert(new_top < top);
-       i = top;
-       do {
-               entry = environment_stack[i - 1];
-
-               symbol_t *symbol = entry->symbol;
+       for(i = top; i > new_top; --i) {
+               stack_entry_t *entry = & environment_stack[i - 1];
 
-               symbol->declaration = entry->old_declaration;
-               symbol->context     = entry->old_context;
+               declaration_t *old_declaration = entry->old_declaration;
+               symbol_t      *symbol          = entry->symbol;
+               namespace_t    namespace       = entry->namespace;
 
-               --i;
-       } while(i != new_top);
-       obstack_free(&environment_obstack, entry);
+               /* replace/remove declaration */
+               declaration_t *declaration = symbol->declaration;
+               assert(declaration != NULL);
+               if(declaration->namespace == namespace) {
+                       if(old_declaration == NULL) {
+                               symbol->declaration = declaration->symbol_next;
+                       } else {
+                               symbol->declaration = old_declaration;
+                               assert(old_declaration->symbol_next ==
+                                      declaration->symbol_next);
+                       }
+               } else {
+                       for(; declaration != NULL; declaration = declaration->symbol_next) {
+                               declaration_t *symbol_next = declaration->symbol_next;
+                               if(symbol_next->namespace == namespace) {
+                                       declaration->symbol_next = old_declaration;
+                                       assert(old_declaration->symbol_next
+                                               == symbol_next->symbol_next);
+                                       break;
+                               }
+                       }
+                       assert(declaration != NULL);
+               }
+       }
 
        ARR_SHRINKLEN(environment_stack, (int) new_top);
 }
 
 
+static int get_rank(const type_t *type)
+{
+       /* The C-standard allows promoting to int or unsigned int (see Â§ 7.2.2
+        * and esp. footnote 108). However we can't fold constants (yet), so we
+        * can't decide wether unsigned int is possible, while int always works.
+        * (unsigned int would be preferable when possible... for stuff like
+        *  struct { enum { ... } bla : 4; } ) */
+       if(type->type == TYPE_ENUM)
+               return ATOMIC_TYPE_INT;
+
+       assert(type->type == TYPE_ATOMIC);
+       atomic_type_t      *atomic_type = (atomic_type_t*) type;
+       atomic_type_type_t  atype       = atomic_type->atype;
+       return atype;
+}
+
+static type_t *promote_integer(type_t *type)
+{
+       if(get_rank(type) < ATOMIC_TYPE_INT)
+               type = type_int;
+
+       return type;
+}
+
+static expression_t *create_cast_expression(expression_t *expression,
+                                            type_t *dest_type)
+{
+       unary_expression_t *cast = allocate_ast_zero(sizeof(cast[0]));
+
+       cast->expression.type     = EXPR_UNARY;
+       cast->type                = UNEXPR_CAST;
+       cast->value               = expression;
+       cast->expression.datatype = dest_type;
+
+       return (expression_t*) cast;
+}
+
+static expression_t *create_implicit_cast(expression_t *expression,
+                                          type_t *dest_type)
+{
+       assert(expression->datatype != NULL);
+       type_t *source_type = expression->datatype;
+
+       source_type = skip_typeref(source_type);
+       dest_type   = skip_typeref(dest_type);
+
+       if(expression->datatype == dest_type)
+               return expression;
+
+       if(dest_type->type == TYPE_ATOMIC) {
+               if(source_type->type != TYPE_ATOMIC)
+                       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->source_position,
+                                               source_type, dest_type);
+                       return expression;
+               }
+
+               return create_cast_expression(expression, dest_type);
+       }
+       if(dest_type->type == TYPE_POINTER) {
+               if(source_type->type == TYPE_POINTER) {
+                       if(!pointers_compatible(source_type, dest_type)) {
+                               type_error_incompatible("can't implicitely cast types",
+                                               expression->source_position,
+                                               source_type, dest_type);
+                       } else {
+                               return create_cast_expression(expression, dest_type);
+                       }
+               }
+       }
+
+       panic("casting of non-atomic types not implemented yet");
+}
+
+static void semantic_assign(type_t *orig_type_left, expression_t **right,
+                            const char *context)
+{
+       type_t *orig_type_right = (*right)->datatype;
+       type_t *type_left       = skip_typeref(orig_type_left);
+       type_t *type_right      = skip_typeref(orig_type_right);
+
+       if(type_left == type_right) {
+               /* fine */
+       } else if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
+               *right = create_implicit_cast(*right, type_left);
+       } else if(type_left->type == TYPE_POINTER
+                       && type_right->type == TYPE_POINTER) {
+               /* TODO */
+       } else {
+               /* TODO: improve error message */
+               parser_print_error_prefix();
+               fprintf(stderr, "incompatible types in %s\n", context);
+               parser_print_error_prefix();
+               print_type(type_left);
+               fputs(" <- ", stderr);
+               print_type(type_right);
+               fputs("\n", stderr);
+       }
+
+}
 
 static expression_t *parse_constant_expression(void)
 {
-       /* TODO: not correct yet */
-       return parse_expression();
+       /* start parsing at precedence 7 (conditional expression) */
+       return parse_sub_expression(7);
 }
 
 static expression_t *parse_assignment_expression(void)
 {
-       /* TODO: not correct yet */
-       return parse_expression();
+       /* start parsing at precedence 2 (assignment expression) */
+       return parse_sub_expression(2);
 }
 
 static void parse_compound_type_entries(void);
-static void parse_declarator(declaration_t *declaration,
-                             storage_class_t storage_class, type_t *type,
-                             int may_be_abstract);
+static declaration_t *parse_declarator(storage_class_t storage_class,
+               type_t *type, int may_be_abstract);
 static declaration_t *record_declaration(declaration_t *declaration);
 
 typedef struct declaration_specifiers_t  declaration_specifiers_t;
@@ -350,19 +614,177 @@ struct declaration_specifiers_t {
        type_t          *type;
 };
 
-static compound_type_t *find_compound_type(compound_type_t *types,
-                                           const symbol_t *symbol)
+static const char *parse_string_literals(void)
 {
-       compound_type_t *type = types;
-       for( ; type != NULL; type = type->next) {
-               if(type->symbol == symbol)
-                       return type;
+       assert(token.type == T_STRING_LITERAL);
+       const char *result = token.v.string;
+
+       next_token();
+
+       while(token.type == T_STRING_LITERAL) {
+               result = concat_strings(result, token.v.string);
+               next_token();
        }
 
-       return NULL;
+       return result;
 }
 
-static type_t *parse_compound_type_specifier(int is_struct)
+static void parse_attributes(void)
+{
+       while(true) {
+               switch(token.type) {
+               case T___attribute__:
+                       next_token();
+
+                       expect_void('(');
+                       int depth = 1;
+                       while(depth > 0) {
+                               switch(token.type) {
+                               case T_EOF:
+                                       parse_error("EOF while parsing attribute");
+                                       break;
+                               case '(':
+                                       next_token();
+                                       depth++;
+                                       break;
+                               case ')':
+                                       next_token();
+                                       depth--;
+                                       break;
+                               default:
+                                       next_token();
+                               }
+                       }
+                       break;
+               case T_asm:
+                       next_token();
+                       expect_void('(');
+                       if(token.type != T_STRING_LITERAL) {
+                               parse_error_expected("while parsing assembler attribute",
+                                                    T_STRING_LITERAL);
+                               eat_brace();
+                               break;
+                       } else {
+                               parse_string_literals();
+                       }
+                       expect_void(')');
+                       break;
+               default:
+                       goto attributes_finished;
+               }
+       }
+
+attributes_finished:
+       ;
+}
+
+static designator_t *parse_designation(void)
+{
+       if(token.type != '[' && token.type != '.')
+               return NULL;
+
+       designator_t *result = NULL;
+       designator_t *last   = NULL;
+
+       while(1) {
+               designator_t *designator;
+               switch(token.type) {
+               case '[':
+                       designator = allocate_ast_zero(sizeof(designator[0]));
+                       next_token();
+                       designator->array_access = parse_constant_expression();
+                       expect(']');
+                       break;
+               case '.':
+                       designator = allocate_ast_zero(sizeof(designator[0]));
+                       next_token();
+                       if(token.type != T_IDENTIFIER) {
+                               parse_error_expected("problem while parsing designator",
+                                                    T_IDENTIFIER, 0);
+                               return NULL;
+                       }
+                       designator->symbol = token.v.symbol;
+                       next_token();
+                       break;
+               default:
+                       expect('=');
+                       return result;
+               }
+
+               assert(designator != NULL);
+               if(last != NULL) {
+                       last->next = designator;
+               } else {
+                       result = designator;
+               }
+               last = designator;
+       }
+}
+
+static initializer_t *parse_initializer_list(type_t *type);
+
+static initializer_t *parse_initializer(type_t *type)
+{
+       designator_t *designator = parse_designation();
+
+       initializer_t *result;
+       if(token.type == '{') {
+               result = parse_initializer_list(type);
+       } else {
+               result          = allocate_ast_zero(sizeof(result[0]));
+               result->type    = INITIALIZER_VALUE;
+               result->v.value = parse_assignment_expression();
+
+               if(type != NULL) {
+                       semantic_assign(type, &result->v.value, "initializer");
+               }
+       }
+       result->designator = designator;
+
+       return result;
+}
+
+static initializer_t *parse_initializer_list(type_t *type)
+{
+       eat('{');
+
+       /* TODO: semantic */
+       (void) type;
+
+       initializer_t *result = allocate_ast_zero(sizeof(result[0]));
+       result->type = INITIALIZER_LIST;
+
+       initializer_t *last = NULL;
+       while(1) {
+               initializer_t *initializer = parse_initializer(NULL);
+               if(last != NULL) {
+                       last->next = initializer;
+               } else {
+                       result->v.list = initializer;
+               }
+               last = initializer;
+
+               if(token.type == '}')
+                       break;
+
+               if(token.type != ',') {
+                       parse_error_expected("problem while parsing initializer list",
+                                            ',', '}', 0);
+                       eat_block();
+                       return result;
+               }
+               eat(',');
+
+               if(token.type == '}')
+                       break;
+       }
+
+       expect('}');
+
+       return result;
+}
+
+static declaration_t *parse_compound_type_specifier(bool is_struct)
 {
        if(is_struct) {
                eat(T_struct);
@@ -370,203 +792,212 @@ static type_t *parse_compound_type_specifier(int is_struct)
                eat(T_union);
        }
 
-       symbol_t        *symbol        = NULL;
-       compound_type_t *compound_type = NULL;
+       symbol_t      *symbol      = NULL;
+       declaration_t *declaration = NULL;
 
        if(token.type == T_IDENTIFIER) {
                symbol = token.v.symbol;
                next_token();
 
-               if(context != NULL) {
-                       if(is_struct) {
-                               compound_type = find_compound_type(context->structs, symbol);
-                       } else {
-                               compound_type = find_compound_type(context->unions, symbol);
-                       }
+               if(is_struct) {
+                       declaration = get_declaration(symbol, NAMESPACE_STRUCT);
+               } else {
+                       declaration = get_declaration(symbol, NAMESPACE_UNION);
                }
        } else if(token.type != '{') {
                if(is_struct) {
-                       parse_error_expected("problem while parsing struct type specifiers",
+                       parse_error_expected("problem while parsing struct type specifier",
                                             T_IDENTIFIER, '{', 0);
                } else {
-                       parse_error_expected("problem while parsing union type specifiers",
+                       parse_error_expected("problem while parsing union type specifier",
                                             T_IDENTIFIER, '{', 0);
                }
 
                return NULL;
        }
 
-       if(compound_type == NULL) {
-               compound_type = allocate_type_zero(sizeof(compound_type[0]));
+       if(declaration == NULL) {
+               declaration = allocate_type_zero(sizeof(declaration[0]));
 
                if(is_struct) {
-                       compound_type->type.type = TYPE_COMPOUND_STRUCT;
+                       declaration->namespace = NAMESPACE_STRUCT;
                } else {
-                       compound_type->type.type = TYPE_COMPOUND_UNION;
+                       declaration->namespace = NAMESPACE_UNION;
                }
-               compound_type->source_position = token.source_position;
-               compound_type->symbol          = symbol;
+               declaration->source_position = token.source_position;
+               declaration->symbol          = symbol;
        }
 
        if(token.type == '{') {
-               if(compound_type->defined) {
+               if(declaration->init.is_defined) {
+                       assert(symbol != NULL);
                        parser_print_error_prefix();
                        fprintf(stderr, "multiple definition of %s %s\n",
                                        is_struct ? "struct" : "union", symbol->string);
-                       compound_type->context.declarations = NULL;
+                       declaration->context.declarations = NULL;
                }
-               compound_type->defined = 1;
+               record_declaration(declaration);
+               declaration->init.is_defined = true;
 
                int         top          = environment_top();
                context_t  *last_context = context;
-               set_context(&compound_type->context);
+               set_context(& declaration->context);
 
                parse_compound_type_entries();
+               parse_attributes();
 
-               assert(context == &compound_type->context);
+               assert(context == & declaration->context);
                set_context(last_context);
                environment_pop_to(top);
        }
 
-       return (type_t*) compound_type;
+       return declaration;
 }
 
-static enum_entry_t *parse_enum_type_entries(void)
+static void parse_enum_entries(void)
 {
        eat('{');
 
        if(token.type == '}') {
                next_token();
                parse_error("empty enum not allowed");
-               return NULL;
+               return;
        }
 
-       enum_entry_t *result     = NULL;
-       enum_entry_t *last_entry = NULL;
        do {
-               enum_entry_t *entry = allocate_ast_zero(sizeof(entry[0]));
+               declaration_t *entry = allocate_ast_zero(sizeof(entry[0]));
+
                if(token.type != T_IDENTIFIER) {
                        parse_error_expected("problem while parsing enum entry",
                                             T_IDENTIFIER, 0);
                        eat_block();
-                       return result;
+                       return;
                }
-               entry->symbol = token.v.symbol;
+               entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
+               entry->symbol          = token.v.symbol;
+               entry->source_position = token.source_position;
                next_token();
 
                if(token.type == '=') {
                        next_token();
-                       entry->value = parse_constant_expression();
+                       entry->init.initializer = parse_initializer(type_int);
                }
 
-               if(last_entry != NULL) {
-                       last_entry->next = entry;
-               } else {
-                       result = entry;
-               }
-               last_entry = entry;
+               record_declaration(entry);
 
                if(token.type != ',')
                        break;
                next_token();
        } while(token.type != '}');
 
-       expect('}');
-       return result;
+       expect_void('}');
 }
 
-static type_t *parse_enum_specifier(void)
+static declaration_t *parse_enum_specifier(void)
 {
        eat(T_enum);
 
-       enum_type_t *enum_type     = allocate_type_zero(sizeof(enum_type[0]));
-       enum_type->type.type       = TYPE_ENUM;
-       enum_type->source_position = token.source_position;
-
-       /* TODO: rewrite to the same style as struct/union above to handle
-        * type identities correctly
-        */
+       declaration_t *declaration;
+       symbol_t      *symbol;
 
        if(token.type == T_IDENTIFIER) {
-               enum_type->symbol = token.v.symbol;
+               symbol = token.v.symbol;
                next_token();
-               if(token.type == '{') {
-                       enum_type->entries = parse_enum_type_entries();
-               }
-       } else if(token.type == '{') {
-               enum_type->entries = parse_enum_type_entries();
+
+               declaration = get_declaration(symbol, NAMESPACE_ENUM);
+       } else if(token.type != '{') {
+               parse_error_expected("problem while parsing enum type specifier",
+                                    T_IDENTIFIER, '{', 0);
+               return NULL;
        } else {
-               parse_error_expected("problem while parsing enum type specifiers",
-                                    T_IDENTIFIER, '{');
+               declaration = NULL;
+               symbol      = NULL;
        }
 
-       return (type_t*) enum_type;
-}
+       if(declaration == NULL) {
+               declaration = allocate_type_zero(sizeof(declaration[0]));
 
-static
-const char *parse_string_literals(void)
-{
-       assert(token.type == T_STRING_LITERAL);
-       const char *result = token.v.string;
+               declaration->namespace       = NAMESPACE_ENUM;
+               declaration->source_position = token.source_position;
+               declaration->symbol          = symbol;
+       }
 
-       next_token();
+       if(token.type == '{') {
+               if(declaration->init.is_defined) {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "multiple definitions of enum %s\n",
+                               symbol->string);
+               }
+               record_declaration(declaration);
+               declaration->init.is_defined = 1;
 
-       while(token.type == T_STRING_LITERAL) {
-               result = concat_strings(result, token.v.string);
-               next_token();
+               parse_enum_entries();
+               parse_attributes();
        }
 
-       return result;
+       return declaration;
 }
 
-static
-void parse_attributes(void)
+/**
+ * if a symbol is a typedef to another type, return true
+ */
+static bool is_typedef_symbol(symbol_t *symbol)
 {
-       while(1) {
-               switch(token.type) {
-               case T___attribute__:
-                       next_token();
+       declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
+       if(declaration == NULL
+                       || declaration->storage_class != STORAGE_CLASS_TYPEDEF)
+               return false;
 
-                       expect_void('(');
-                       int depth = 1;
-                       while(depth > 0) {
-                               switch(token.type) {
-                               case T_EOF:
-                                       parse_error("EOF while parsing attribute");
-                                       break;
-                               case '(':
-                                       next_token();
-                                       depth++;
-                                       break;
-                               case ')':
-                                       next_token();
-                                       depth--;
-                                       break;
-                               default:
-                                       next_token();
-                               }
-                       }
-                       break;
-               case T_asm:
+       return true;
+}
+
+static type_t *parse_typeof(void)
+{
+       eat(T___typeof__);
+
+       type_t *type;
+
+       expect('(');
+
+       expression_t *expression  = NULL;
+
+restart:
+       switch(token.type) {
+       case T___extension__:
+               /* this can be a prefix to a typename or an expression */
+               /* we simply eat it now. */
+               do {
                        next_token();
-                       expect_void('(');
-                       if(token.type != T_STRING_LITERAL) {
-                               parse_error_expected("while parsing assembler attribute",
-                                                    T_STRING_LITERAL);
-                               eat_brace();
-                               break;
-                       } else {
-                               parse_string_literals();
-                       }
-                       expect_void(')');
-                       break;
-               default:
-                       goto attributes_finished;
+               } while(token.type == T___extension__);
+               goto restart;
+
+       case T_IDENTIFIER:
+               if(is_typedef_symbol(token.v.symbol)) {
+                       type = parse_typename();
+               } else {
+                       expression = parse_expression();
+                       type       = expression->datatype;
                }
+               break;
+
+       TYPENAME_START
+               type = parse_typename();
+               break;
+
+       default:
+               expression = parse_expression();
+               type       = expression->datatype;
+               break;
        }
 
-attributes_finished:
-       ;
+       expect(')');
+
+       typeof_type_t *typeof = allocate_type_zero(sizeof(typeof[0]));
+       typeof->type.type     = TYPE_TYPEOF;
+       typeof->expression    = expression;
+       typeof->typeof_type   = type;
+
+       return (type_t*) typeof;
 }
 
 typedef enum {
@@ -589,81 +1020,39 @@ typedef enum {
 #endif
 } specifiers_t;
 
-#define STORAGE_CLASSES     \
-       case T_typedef:         \
-       case T_extern:          \
-       case T_static:          \
-       case T_auto:            \
-       case T_register:
-
-#define TYPE_QUALIFIERS     \
-       case T_const:           \
-       case T_restrict:        \
-       case T_volatile:        \
-       case T_inline:          \
-       case T___extension__:
-
-#ifdef PROVIDE_COMPLEX
-#define COMPLEX_SPECIFIERS  \
-       case T__Complex:
-#else
-#define COMPLEX_SPECIFIERS
-#endif
-
-#ifdef PROVIDE_IMAGINARY
-#define IMAGINARY_SPECIFIERS \
-       case T__Imaginary:
-#else
-#define IMAGINARY_SPECIFIERS
-#endif
-
-#define TYPE_SPECIFIERS     \
-       case T_void:            \
-       case T_char:            \
-       case T_short:           \
-       case T_int:             \
-       case T_long:            \
-       case T_float:           \
-       case T_double:          \
-       case T_signed:          \
-       case T_unsigned:        \
-       case T__Bool:           \
-       case T_struct:          \
-       case T_union:           \
-       case T_enum:            \
-       COMPLEX_SPECIFIERS      \
-       IMAGINARY_SPECIFIERS
-
-#define DECLARATION_START   \
-       STORAGE_CLASSES         \
-       TYPE_QUALIFIERS         \
-       TYPE_SPECIFIERS
-
-static
-type_t *create_builtin_type(symbol_t *symbol)
+static type_t *create_builtin_type(symbol_t *symbol)
 {
        builtin_type_t *type = allocate_type_zero(sizeof(type[0]));
        type->type.type      = TYPE_BUILTIN;
        type->symbol         = symbol;
+       /* TODO... */
+       type->real_type      = type_int;
 
-       type_t *result = typehash_insert((type_t*) type);
-       if(result != (type_t*) type) {
-               obstack_free(type_obst, type);
-       }
+       return (type_t*) type;
+}
 
-       return result;
+static type_t *get_typedef_type(symbol_t *symbol)
+{
+       declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
+       if(declaration == NULL
+                       || declaration->storage_class != STORAGE_CLASS_TYPEDEF)
+               return NULL;
+
+       typedef_type_t *typedef_type = allocate_type_zero(sizeof(typedef_type[0]));
+       typedef_type->type.type    = TYPE_TYPEDEF;
+       typedef_type->declaration  = declaration;
+
+       return (type_t*) typedef_type;
 }
 
-static
-void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
+static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
 {
-       declaration_t *declaration;
        type_t        *type            = NULL;
        unsigned       type_qualifiers = 0;
        unsigned       type_specifiers = 0;
        int            newtype         = 0;
 
-       while(1) {
+       while(true) {
                switch(token.type) {
 
                /* storage class */
@@ -737,15 +1126,36 @@ void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                        }
                        break;
 
-               /* TODO: if type != NULL for the following rules issue an error */
-               case T_struct:
-                       type = parse_compound_type_specifier(1);
+               /* TODO: if type != NULL for the following rules should issue
+                * an error */
+               case T_struct: {
+                       compound_type_t *compound_type
+                               = allocate_type_zero(sizeof(compound_type[0]));
+                       compound_type->type.type = TYPE_COMPOUND_STRUCT;
+                       compound_type->declaration = parse_compound_type_specifier(true);
+
+                       type = (type_t*) compound_type;
                        break;
-               case T_union:
-                       type = parse_compound_type_specifier(0);
+               }
+               case T_union: {
+                       compound_type_t *compound_type
+                               = allocate_type_zero(sizeof(compound_type[0]));
+                       compound_type->type.type = TYPE_COMPOUND_UNION;
+                       compound_type->declaration = parse_compound_type_specifier(false);
+
+                       type = (type_t*) compound_type;
                        break;
-               case T_enum:
-                       type = parse_enum_specifier();
+               }
+               case T_enum: {
+                       enum_type_t *enum_type = allocate_type_zero(sizeof(enum_type[0]));
+                       enum_type->type.type   = TYPE_ENUM;
+                       enum_type->declaration = parse_enum_specifier();
+
+                       type = (type_t*) enum_type;
+                       break;
+               }
+               case T___typeof__:
+                       type = parse_typeof();
                        break;
                case T___builtin_va_list:
                        type = create_builtin_type(token.v.symbol);
@@ -757,17 +1167,16 @@ void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                        parse_attributes();
                        break;
 
-               case T_IDENTIFIER:
-                       declaration = token.v.symbol->declaration;
-                       if(declaration == NULL ||
-                                       declaration->storage_class != STORAGE_CLASS_TYPEDEF) {
+               case T_IDENTIFIER: {
+                       type_t *typedef_type = get_typedef_type(token.v.symbol);
+
+                       if(typedef_type == NULL)
                                goto finish_specifiers;
-                       }
 
-                       type = declaration->type;
-                       assert(type != NULL);
                        next_token();
+                       type = typedef_type;
                        break;
+               }
 
                /* function specifier */
                default:
@@ -872,7 +1281,13 @@ finish_specifiers:
                default:
                        /* invalid specifier combination, give an error message */
                        if(type_specifiers == 0) {
+#ifndef STRICT_C99
+                               parse_warning("no type specifiers in declaration (using int)");
+                               atomic_type = ATOMIC_TYPE_INT;
+                               break;
+#else
                                parse_error("no type specifiers given in declaration");
+#endif
                        } else if((type_specifiers & SPECIFIER_SIGNED) &&
                                  (type_specifiers & SPECIFIER_UNSIGNED)) {
                                parse_error("signed and unsigned specifiers gives");
@@ -900,85 +1315,33 @@ finish_specifiers:
 
        type_t *result = typehash_insert(type);
        if(newtype && result != (type_t*) type) {
-               obstack_free(type_obst, type);
+               free_type(type);
        }
 
        specifiers->type = result;
 }
 
-static
-unsigned parse_type_qualifiers(void)
+static type_qualifier_t parse_type_qualifiers(void)
 {
-       unsigned type_qualifiers = 0;
+       type_qualifier_t type_qualifiers = 0;
 
-       while(1) {
+       while(true) {
                switch(token.type) {
                /* type qualifiers */
                MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
                MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
-               MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
-               MATCH_TYPE_QUALIFIER(T_inline,   TYPE_QUALIFIER_INLINE);
-
-               default:
-                       return type_qualifiers;
-               }
-       }
-}
-
-typedef struct parsed_pointer_t parsed_pointer_t;
-struct parsed_pointer_t {
-       unsigned          type_qualifiers;
-       parsed_pointer_t *next;
-};
-
-static
-parsed_pointer_t *parse_pointers(void)
-{
-       parsed_pointer_t *result       = NULL;
-       parsed_pointer_t *last_pointer = NULL;
-
-       while(token.type == '*') {
-               next_token();
-               parsed_pointer_t *pointer
-                       = obstack_alloc(&temp_obst, sizeof(pointer[0]));
-               pointer->type_qualifiers = parse_type_qualifiers();
-
-               if(last_pointer != NULL) {
-                       last_pointer->next = pointer;
-               } else {
-                       result = pointer;
-               }
-               last_pointer = pointer;
-       }
-
-       return result;
-}
-
-static
-type_t *make_pointers(type_t *type, parsed_pointer_t *pointer)
-{
-       for( ; pointer != NULL; pointer = pointer->next) {
-               pointer_type_t *pointer_type
-                       = allocate_type_zero(sizeof(pointer_type[0]));
-               pointer_type->type.type       = TYPE_POINTER;
-               pointer_type->points_to       = type;
-               pointer_type->type.qualifiers = pointer->type_qualifiers;
+               MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
+               MATCH_TYPE_QUALIFIER(T_inline,   TYPE_QUALIFIER_INLINE);
 
-               type_t *result = typehash_insert((type_t*) pointer_type);
-               if(result != (type_t*) pointer_type) {
-                       obstack_free(type_obst, pointer_type);
+               default:
+                       return type_qualifiers;
                }
-
-               type = result;
        }
-
-       return type;
 }
 
-static
-void parse_identifier_list(void)
+static void parse_identifier_list(void)
 {
-       while(1) {
+       while(true) {
                if(token.type != T_IDENTIFIER) {
                        parse_error_expected("problem while parsing parameter identifier "
                                             "list", T_IDENTIFIER, 0);
@@ -991,29 +1354,29 @@ void parse_identifier_list(void)
        }
 }
 
-static
-declaration_t *parse_parameter(void)
+static declaration_t *parse_parameter(void)
 {
        declaration_specifiers_t specifiers;
        memset(&specifiers, 0, sizeof(specifiers));
 
        parse_declaration_specifiers(&specifiers);
 
-       declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0]));
-       parse_declarator(declaration, specifiers.storage_class,
-                        specifiers.type, 1);
+       declaration_t *declaration = parse_declarator(specifiers.storage_class,
+                                                     specifiers.type, 1);
+
+       /* TODO check declaration constraints for parameters */
+       if(declaration->storage_class == STORAGE_CLASS_TYPEDEF) {
+               parse_error("typedef not allowed in parameter list");
+       }
 
        return declaration;
 }
 
-static
-declaration_t *parse_parameters(method_type_t *type)
+static declaration_t *parse_parameters(function_type_t *type)
 {
        if(token.type == T_IDENTIFIER) {
-               symbol_t      *symbol      = token.v.symbol;
-               declaration_t *declaration = symbol->declaration;
-               if(declaration == NULL
-                               || declaration->storage_class != STORAGE_CLASS_TYPEDEF) {
+               symbol_t      *symbol = token.v.symbol;
+               if(!is_typedef_symbol(symbol)) {
                        /* TODO */
                        parse_identifier_list();
                        return NULL;
@@ -1029,13 +1392,13 @@ declaration_t *parse_parameters(method_type_t *type)
                return NULL;
        }
 
-       declaration_t      *declarations = NULL;
-       declaration_t      *declaration;
-       declaration_t      *last_declaration = NULL;
-       method_parameter_t *parameter;
-       method_parameter_t *last_parameter = NULL;
+       declaration_t        *declarations = NULL;
+       declaration_t        *declaration;
+       declaration_t        *last_declaration = NULL;
+       function_parameter_t *parameter;
+       function_parameter_t *last_parameter = NULL;
 
-       while(1) {
+       while(true) {
                switch(token.type) {
                case T_DOTDOTDOT:
                        next_token();
@@ -1043,6 +1406,7 @@ declaration_t *parse_parameters(method_type_t *type)
                        return declarations;
 
                case T_IDENTIFIER:
+               case T___extension__:
                DECLARATION_START
                        declaration = parse_parameter();
 
@@ -1069,26 +1433,133 @@ declaration_t *parse_parameters(method_type_t *type)
        }
 }
 
-typedef struct declarator_part declarator_part;
-struct declarator_part {
-       parsed_pointer_t *pointers;
-       method_type_t    *method_type;
-       declarator_part  *inner;
+typedef enum {
+       CONSTRUCT_POINTER,
+       CONSTRUCT_FUNCTION,
+       CONSTRUCT_ARRAY
+} construct_type_type_t;
+
+typedef struct construct_type_t construct_type_t;
+struct construct_type_t {
+       construct_type_type_t  type;
+       construct_type_t      *next;
+};
+
+typedef struct parsed_pointer_t parsed_pointer_t;
+struct parsed_pointer_t {
+       construct_type_t  construct_type;
+       type_qualifier_t  type_qualifiers;
+};
+
+typedef struct construct_function_type_t construct_function_type_t;
+struct construct_function_type_t {
+       construct_type_t    construct_type;
+       function_type_t    *function_type;
+};
+
+typedef struct parsed_array_t parsed_array_t;
+struct parsed_array_t {
+       construct_type_t  construct_type;
+       type_qualifier_t  type_qualifiers;
+       bool              is_static;
+       bool              is_variable;
+       expression_t     *size;
+};
+
+typedef struct construct_base_type_t construct_base_type_t;
+struct construct_base_type_t {
+       construct_type_t  construct_type;
+       type_t           *type;
 };
 
+static construct_type_t *parse_pointer_declarator(void)
+{
+       eat('*');
+
+       parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
+       memset(pointer, 0, sizeof(pointer[0]));
+       pointer->type_qualifiers = parse_type_qualifiers();
+
+       return (construct_type_t*) pointer;
+}
+
+static construct_type_t *parse_array_declarator(void)
+{
+       eat('[');
+
+       parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
+       memset(array, 0, sizeof(array[0]));
+
+       if(token.type == T_static) {
+               array->is_static = true;
+               next_token();
+       }
+
+       type_qualifier_t type_qualifiers = parse_type_qualifiers();
+       if(type_qualifiers != 0) {
+               if(token.type == T_static) {
+                       array->is_static = true;
+                       next_token();
+               }
+       }
+       array->type_qualifiers = type_qualifiers;
+
+       if(token.type == '*' && look_ahead(1)->type == ']') {
+               array->is_variable = true;
+               next_token();
+       } else if(token.type != ']') {
+               array->size = parse_assignment_expression();
+       }
+
+       expect(']');
+
+       return (construct_type_t*) array;
+}
+
+static construct_type_t *parse_function_declarator(declaration_t *declaration)
+{
+       eat('(');
+
+       function_type_t *type = allocate_type_zero(sizeof(type[0]));
+       type->type.type       = TYPE_FUNCTION;
+
+       declaration_t *parameters = parse_parameters(type);
+       if(declaration != NULL) {
+               declaration->context.declarations = parameters;
+       }
+
+       construct_function_type_t *construct_function_type =
+               obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
+       memset(construct_function_type, 0, sizeof(construct_function_type[0]));
+       construct_function_type->construct_type.type = CONSTRUCT_FUNCTION;
+       construct_function_type->function_type       = type;
+
+       expect(')');
+
+       return (construct_type_t*) construct_function_type;
+}
 
-static
-declarator_part *parse_inner_declarator(declaration_t *declaration,
-                                        int may_be_abstract)
+static construct_type_t *parse_inner_declarator(declaration_t *declaration,
+               int may_be_abstract)
 {
-       declarator_part *part = obstack_alloc(&temp_obst, sizeof(part[0]));
-       memset(part, 0, sizeof(part[0]));
+       construct_type_t *result = NULL;
+       construct_type_t *last   = NULL;
 
-       part->pointers = parse_pointers();
+       while(token.type == '*') {
+               construct_type_t *type = parse_pointer_declarator();
+               if(last != NULL) {
+                       last->next = type;
+               } else {
+                       result = type;
+               }
+               last = type;
+       }
 
        /* TODO: find out if this is correct */
        parse_attributes();
 
+       construct_type_t *inner_types = NULL;
+
        switch(token.type) {
        case T_IDENTIFIER:
                if(declaration == NULL) {
@@ -1101,7 +1572,7 @@ declarator_part *parse_inner_declarator(declaration_t *declaration,
                break;
        case '(':
                next_token();
-               part->inner = parse_inner_declarator(declaration, may_be_abstract);
+               inner_types = parse_inner_declarator(declaration, may_be_abstract);
                expect(')');
                break;
        default:
@@ -1111,135 +1582,151 @@ declarator_part *parse_inner_declarator(declaration_t *declaration,
                                     '(', 0);
        }
 
-       while(1) {
+       while(true) {
+               construct_type_t *type;
                switch(token.type) {
                case '(':
-                       next_token();
-
-                       method_type_t *method_type
-                               = allocate_type_zero(sizeof(method_type[0]));
-                       method_type->type.type   = TYPE_METHOD;
-
-                       declaration_t *parameters = parse_parameters(method_type);
-                       if(declaration != NULL) {
-                               declaration->context.declarations = parameters;
-                       }
-
-                       part->method_type = method_type;
-
-                       expect(')');
+                       type = parse_function_declarator(declaration);
                        break;
                case '[':
-                       next_token();
-
-                       if(token.type == T_static) {
-                               next_token();
-                       }
-
-                       unsigned type_qualifiers = parse_type_qualifiers();
-                       if(type_qualifiers != 0) {
-                               if(token.type == T_static) {
-                                       next_token();
-                               }
-                       }
-
-                       /* TODO */
-
-                       if(token.type == '*' && look_ahead(1)->type == ']') {
-                               next_token();
-                       } else if(token.type != ']') {
-                               parse_assignment_expression();
-                       }
-
-                       expect(']');
+                       type = parse_array_declarator();
                        break;
                default:
                        goto declarator_finished;
                }
+
+               if(last != NULL) {
+                       last->next = type;
+               } else {
+                       result = type;
+               }
+               last = type;
        }
 
 declarator_finished:
        parse_attributes();
 
-       return part;
+       if(inner_types != NULL) {
+               if(last != NULL) {
+                       last->next = inner_types;
+               } else {
+                       result = inner_types;
+               }
+               last = inner_types;
+       }
+
+       return result;
 }
 
-static
-type_t *construct_declarator_type(declarator_part *part, type_t *type)
+static type_t *construct_declarator_type(construct_type_t *construct_list,
+                                         type_t *type)
 {
-       do {
-               type = make_pointers(type, part->pointers);
+       construct_type_t *iter = construct_list;
+       for( ; iter != NULL; iter = iter->next) {
+               parsed_pointer_t          *parsed_pointer;
+               parsed_array_t            *parsed_array;
+               construct_function_type_t *construct_function_type;
+               function_type_t           *function_type;
+               pointer_type_t            *pointer_type;
+               array_type_t              *array_type;
 
-               method_type_t *method_type = part->method_type;
-               if(method_type != NULL) {
-                       method_type->result_type = type;
+               switch(iter->type) {
+               case CONSTRUCT_FUNCTION:
+                       construct_function_type = (construct_function_type_t*) iter;
+                       function_type           = construct_function_type->function_type;
 
-                       type_t *result = typehash_insert((type_t*) method_type);
-                       if(result != (type_t*) method_type) {
-                               obstack_free(type_obst, method_type);
-                       }
-                       type = result;
+                       function_type->result_type = type;
+                       type                       = (type_t*) function_type;
+                       break;
+
+               case CONSTRUCT_POINTER:
+                       parsed_pointer = (parsed_pointer_t*) iter;
+                       pointer_type   = allocate_type_zero(sizeof(pointer_type[0]));
+
+                       pointer_type->type.type       = TYPE_POINTER;
+                       pointer_type->points_to       = type;
+                       pointer_type->type.qualifiers = parsed_pointer->type_qualifiers;
+                       type                          = (type_t*) pointer_type;
+                       break;
+
+               case CONSTRUCT_ARRAY:
+                       parsed_array  = (parsed_array_t*) iter;
+                       array_type    = allocate_type_zero(sizeof(array_type[0]));
+
+                       array_type->type.type       = TYPE_ARRAY;
+                       array_type->element_type    = type;
+                       array_type->type.qualifiers = parsed_array->type_qualifiers;
+                       array_type->is_static       = parsed_array->is_static;
+                       array_type->is_variable     = parsed_array->is_variable;
+                       array_type->size            = parsed_array->size;
+                       type                        = (type_t*) array_type;
+                       break;
                }
 
-               part = part->inner;
-       } while(part != NULL);
+               type_t *hashed_type = typehash_insert((type_t*) type);
+               if(hashed_type != type) {
+                       free_type(type);
+                       type = hashed_type;
+               }
+       }
 
        return type;
 }
 
-static
-void parse_declarator(declaration_t *declaration, storage_class_t storage_class,
-                      type_t *type, int may_be_abstract)
+static declaration_t *parse_declarator(storage_class_t storage_class,
+               type_t *type, int may_be_abstract)
 {
-       declarator_part *part
+       declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0]));
+       declaration->storage_class = storage_class;
+
+       construct_type_t *construct_type
                = parse_inner_declarator(declaration, may_be_abstract);
+       declaration->type = construct_declarator_type(construct_type, type);
 
-       if(part != NULL) {
-               declaration->type          = construct_declarator_type(part, type);
-               declaration->storage_class = storage_class;
-               obstack_free(&temp_obst, part);
+       if(construct_type != NULL) {
+               obstack_free(&temp_obst, construct_type);
        }
+
+       return declaration;
 }
 
-static
-type_t *parse_abstract_declarator(type_t *base_type)
+static type_t *parse_abstract_declarator(type_t *base_type)
 {
-       declarator_part *part = parse_inner_declarator(NULL, 1);
-
-       if(part == NULL)
-               return NULL;
+       construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
 
-       type_t *result = construct_declarator_type(part, base_type);
-       obstack_free(&temp_obst, part);
+       type_t *result = construct_declarator_type(construct_type, base_type);
+       if(construct_type != NULL) {
+               obstack_free(&temp_obst, construct_type);
+       }
 
        return result;
 }
 
 static declaration_t *record_declaration(declaration_t *declaration)
 {
-       if(context == NULL)
-               return declaration;
+       assert(context != NULL);
 
        symbol_t *symbol = declaration->symbol;
        if(symbol != NULL) {
-               declaration_t *alias = environment_push(declaration, context);
+               declaration_t *alias = environment_push(declaration);
                if(alias != declaration)
                        return alias;
+       } else {
+               declaration->parent_context = context;
        }
 
        if(last_declaration != NULL) {
                last_declaration->next = declaration;
        } else {
-               context->declarations  = declaration;
+               context->declarations = declaration;
        }
        last_declaration = declaration;
 
        return declaration;
 }
 
-static
-void parser_error_multiple_definition(declaration_t *previous,
-                                      declaration_t *declaration)
+static void parser_error_multiple_definition(declaration_t *previous,
+                                             declaration_t *declaration)
 {
        parser_print_error_prefix_pos(declaration->source_position);
        fprintf(stderr, "multiple definition of symbol '%s'\n",
@@ -1247,44 +1734,43 @@ void parser_error_multiple_definition(declaration_t *previous,
        parser_print_error_prefix_pos(previous->source_position);
        fprintf(stderr, "this is the location of the previous "
                "definition.\n");
+       error();
 }
 
-static
-void parse_init_declarators(const declaration_specifiers_t *specifiers)
+static void parse_init_declarators(const declaration_specifiers_t *specifiers)
 {
-       while(1) {
+       while(true) {
                declaration_t *ndeclaration
-                       = allocate_ast_zero(sizeof(ndeclaration[0]));
+                       = parse_declarator(specifiers->storage_class, specifiers->type, 0);
 
-               parse_declarator(ndeclaration, specifiers->storage_class,
-                                specifiers->type, 0);
                declaration_t *declaration = record_declaration(ndeclaration);
                if(token.type == '=') {
                        next_token();
 
-                       /* TODO: check that this is an allowed type (esp. no method type) */
+                       /* TODO: check that this is an allowed type (no function type) */
 
-                       if(declaration->initializer != NULL) {
+                       if(declaration->init.initializer != NULL) {
                                parser_error_multiple_definition(declaration, ndeclaration);
                        }
 
-                       if(token.type == '{') {
-                               // TODO
-                               expect_void('}');
-                       } else {
-                               declaration->initializer = parse_assignment_expression();
-                       }
+                       ndeclaration->init.initializer = parse_initializer(declaration->type);
                } else if(token.type == '{') {
-                       if(declaration->type->type != TYPE_METHOD) {
+                       if(declaration->type->type != TYPE_FUNCTION) {
                                parser_print_error_prefix();
                                fprintf(stderr, "Declarator ");
-                               print_type(declaration->type, declaration->symbol);
-                               fprintf(stderr, " is not a method type.\n");
+                               print_type_ext(declaration->type, declaration->symbol, NULL);
+                               fprintf(stderr, " has a body but is not a function type.\n");
+                               eat_block();
+                               continue;
                        }
 
-                       if(declaration->initializer != NULL) {
+                       if(declaration->init.statement != NULL) {
                                parser_error_multiple_definition(declaration, ndeclaration);
                        }
+                       if(ndeclaration != declaration) {
+                               memcpy(&declaration->context, &ndeclaration->context,
+                                      sizeof(declaration->context));
+                       }
 
                        int         top          = environment_top();
                        context_t  *last_context = context;
@@ -1293,16 +1779,21 @@ void parse_init_declarators(const declaration_specifiers_t *specifiers)
                        /* push function parameters */
                        declaration_t *parameter = declaration->context.declarations;
                        for( ; parameter != NULL; parameter = parameter->next) {
-                               environment_push(parameter, context);
+                               environment_push(parameter);
                        }
+                       declaration_t *old_current_function = current_function;
+                       current_function                    = declaration;
 
                        statement_t *statement = parse_compound_statement();
 
+                       assert(current_function == declaration);
+                       old_current_function = current_function;
+
                        assert(context == &declaration->context);
                        set_context(last_context);
                        environment_pop_to(top);
 
-                       declaration->statement = statement;
+                       declaration->init.statement = statement;
                        return;
                }
 
@@ -1313,8 +1804,7 @@ void parse_init_declarators(const declaration_specifiers_t *specifiers)
        expect_void(';');
 }
 
-static
-void parse_struct_declarators(const declaration_specifiers_t *specifiers)
+static void parse_struct_declarators(const declaration_specifiers_t *specifiers)
 {
        while(1) {
                if(token.type == ':') {
@@ -1323,10 +1813,10 @@ void parse_struct_declarators(const declaration_specifiers_t *specifiers)
                        /* TODO (bitfields) */
                } else {
                        declaration_t *declaration
-                               = allocate_ast_zero(sizeof(declaration[0]));
-                       parse_declarator(declaration, specifiers->storage_class,
-                                        specifiers->type, 1);
+                               = parse_declarator(specifiers->storage_class,
+                                                  specifiers->type, 1);
 
+                       /* TODO: check constraints for struct declarations */
                        /* TODO: check for doubled fields */
                        record_declaration(declaration);
 
@@ -1351,8 +1841,6 @@ static void parse_compound_type_entries(void)
        while(token.type != '}' && token.type != T_EOF) {
                declaration_specifiers_t specifiers;
                memset(&specifiers, 0, sizeof(specifiers));
-               /* TODO not correct as this allows storage class stuff... but only
-                * specifiers and qualifiers sould be allowed here */
                parse_declaration_specifiers(&specifiers);
 
                parse_struct_declarators(&specifiers);
@@ -1363,20 +1851,29 @@ static void parse_compound_type_entries(void)
        next_token();
 }
 
-void parse_declaration(void)
+static void parse_declaration(void)
 {
+       source_position_t source_position = token.source_position;
+
        declaration_specifiers_t specifiers;
        memset(&specifiers, 0, sizeof(specifiers));
        parse_declaration_specifiers(&specifiers);
 
        if(token.type == ';') {
                next_token();
+
+               declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0]));
+
+               declaration->type            = specifiers.type;
+               declaration->storage_class   = specifiers.storage_class;
+               declaration->source_position = source_position;
+               record_declaration(declaration);
                return;
        }
        parse_init_declarators(&specifiers);
 }
 
-type_t *parse_typename(void)
+static type_t *parse_typename(void)
 {
        declaration_specifiers_t specifiers;
        memset(&specifiers, 0, sizeof(specifiers));
@@ -1410,8 +1907,7 @@ struct expression_parser_function_t {
 
 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
 
-static
-expression_t *expected_expression_error(void)
+static expression_t *expected_expression_error(void)
 {
        parser_print_error_prefix();
        fprintf(stderr, "expected expression, got token ");
@@ -1425,103 +1921,349 @@ expression_t *expected_expression_error(void)
        return expression;
 }
 
-static
-expression_t *parse_string_const(void)
+static expression_t *parse_string_const(void)
 {
        string_literal_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
 
-       cnst->expression.type = EXPR_STRING_LITERAL;
-       cnst->value           = parse_string_literals();
+       cnst->expression.type     = EXPR_STRING_LITERAL;
+       cnst->expression.datatype = type_string;
+       cnst->value               = parse_string_literals();
+
+       return (expression_t*) cnst;
+}
+
+static expression_t *parse_int_const(void)
+{
+       const_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
+
+       cnst->expression.type     = EXPR_CONST;
+       cnst->expression.datatype = type_int;
+       cnst->v.int_value         = token.v.intvalue;
+
+       next_token();
 
        return (expression_t*) cnst;
 }
 
-static
-expression_t *parse_int_const(void)
+static expression_t *parse_float_const(void)
 {
        const_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
 
-       cnst->expression.type = EXPR_CONST;
-       cnst->value           = token.v.intvalue;
+       cnst->expression.type     = EXPR_CONST;
+       cnst->expression.datatype = type_double;
+       cnst->v.float_value       = token.v.floatvalue;
 
        next_token();
 
-       return (expression_t*) cnst;
+       return (expression_t*) cnst;
+}
+
+static declaration_t *create_implicit_function(symbol_t *symbol,
+               const source_position_t source_position)
+{
+       function_type_t *function_type
+               = allocate_type_zero(sizeof(function_type[0]));
+
+       function_type->type.type              = TYPE_FUNCTION;
+       function_type->result_type            = type_int;
+       function_type->unspecified_parameters = true;
+
+       type_t *type = typehash_insert((type_t*) function_type);
+       if(type != (type_t*) function_type) {
+               free_type(function_type);
+       }
+
+       declaration_t *declaration = allocate_ast_zero(sizeof(declaration[0]));
+
+       declaration->storage_class   = STORAGE_CLASS_EXTERN;
+       declaration->type            = type;
+       declaration->symbol          = symbol;
+       declaration->source_position = source_position;
+
+       /* prepend the implicit definition to the global context
+        * this is safe since the symbol wasn't declared as anything else yet
+        */
+       assert(symbol->declaration == NULL);
+
+       context_t *last_context = context;
+       context = global_context;
+
+       environment_push(declaration);
+       declaration->next     = context->declarations;
+       context->declarations = declaration;
+
+       context = last_context;
+
+       return declaration;
+}
+
+static expression_t *parse_reference(void)
+{
+       reference_expression_t *ref = allocate_ast_zero(sizeof(ref[0]));
+
+       ref->expression.type = EXPR_REFERENCE;
+       ref->symbol          = token.v.symbol;
+
+       declaration_t *declaration = get_declaration(ref->symbol, NAMESPACE_NORMAL);
+
+       source_position_t source_position = token.source_position;
+       next_token();
+
+       if(declaration == NULL) {
+#ifndef STRICT_C99
+               /* an implicitely defined function */
+               if(token.type == '(') {
+                       parser_print_prefix_pos(token.source_position);
+                       fprintf(stderr, "warning: implicit declaration of function '%s'\n",
+                               ref->symbol->string);
+
+                       declaration = create_implicit_function(ref->symbol,
+                                                              source_position);
+               } else
+#endif
+               {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "unknown symbol '%s' found.\n", ref->symbol->string);
+                       return (expression_t*) ref;
+               }
+       }
+
+       ref->declaration         = declaration;
+       ref->expression.datatype = declaration->type;
+
+       return (expression_t*) ref;
+}
+
+static void check_cast_allowed(expression_t *expression, type_t *dest_type)
+{
+       (void) expression;
+       (void) dest_type;
+       /* TODO check if explicit cast is allowed and issue warnings/errors */
+}
+
+static expression_t *parse_cast(void)
+{
+       unary_expression_t *cast = allocate_ast_zero(sizeof(cast[0]));
+
+       cast->expression.type            = EXPR_UNARY;
+       cast->type                       = UNEXPR_CAST;
+       cast->expression.source_position = token.source_position;
+
+       type_t *type  = parse_typename();
+
+       expect(')');
+       expression_t *value = parse_sub_expression(20);
+
+       check_cast_allowed(value, type);
+
+       cast->expression.datatype = type;
+       cast->value               = value;
+
+       return (expression_t*) cast;
+}
+
+static expression_t *parse_statement_expression(void)
+{
+       statement_expression_t *expression
+               = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type = EXPR_STATEMENT;
+       expression->statement       = parse_compound_statement();
+
+       /* find last statement and use it's type */
+       const statement_t *last_statement = NULL;
+       const statement_t *statement      = expression->statement;
+       for( ; statement != NULL; statement = statement->next) {
+               last_statement = statement;
+       }
+
+       if(last_statement->type == STATEMENT_EXPRESSION) {
+               const expression_statement_t *expression_statement =
+                       (const expression_statement_t*) last_statement;
+               expression->expression.datatype
+                       = expression_statement->expression->datatype;
+       } else {
+               expression->expression.datatype = type_void;
+       }
+
+       expect(')');
+
+       return (expression_t*) expression;
+}
+
+static expression_t *parse_brace_expression(void)
+{
+       eat('(');
+
+       switch(token.type) {
+       case '{':
+               /* gcc extension: a stement expression */
+               return parse_statement_expression();
+
+       TYPE_QUALIFIERS
+       TYPE_SPECIFIERS
+               return parse_cast();
+       case T_IDENTIFIER:
+               if(is_typedef_symbol(token.v.symbol)) {
+                       return parse_cast();
+               }
+       }
+
+       expression_t *result = parse_expression();
+       expect(')');
+
+       return result;
+}
+
+static expression_t *parse_function_keyword(void)
+{
+       eat(T___FUNCTION__);
+       /* TODO */
+
+       string_literal_t *expression = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type     = EXPR_FUNCTION;
+       expression->expression.datatype = type_string;
+       expression->value               = "TODO: FUNCTION";
+
+       return (expression_t*) expression;
+}
+
+static expression_t *parse_pretty_function_keyword(void)
+{
+       eat(T___PRETTY_FUNCTION__);
+       /* TODO */
+
+       string_literal_t *expression = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type     = EXPR_PRETTY_FUNCTION;
+       expression->expression.datatype = type_string;
+       expression->value               = "TODO: PRETTY FUNCTION";
+
+       return (expression_t*) expression;
+}
+
+static designator_t *parse_designator(void)
+{
+       designator_t *result = allocate_ast_zero(sizeof(result[0]));
+
+       if(token.type != T_IDENTIFIER) {
+               parse_error_expected("problem while parsing member designator",
+                                    T_IDENTIFIER, 0);
+               eat_brace();
+               return NULL;
+       }
+       result->symbol = token.v.symbol;
+       next_token();
+
+       designator_t *last_designator = result;
+       while(true) {
+               if(token.type == '.') {
+                       next_token();
+                       if(token.type != T_IDENTIFIER) {
+                               parse_error_expected("problem while parsing member designator",
+                                       T_IDENTIFIER, 0);
+                               eat_brace();
+                               return NULL;
+                       }
+                       designator_t *designator = allocate_ast_zero(sizeof(result[0]));
+                       designator->symbol       = token.v.symbol;
+                       next_token();
+
+                       last_designator->next = designator;
+                       last_designator       = designator;
+                       continue;
+               }
+               if(token.type == '[') {
+                       next_token();
+                       designator_t *designator = allocate_ast_zero(sizeof(result[0]));
+                       designator->array_access = parse_expression();
+                       if(designator->array_access == NULL) {
+                               eat_brace();
+                               return NULL;
+                       }
+                       expect(']');
+
+                       last_designator->next = designator;
+                       last_designator       = designator;
+                       continue;
+               }
+               break;
+       }
+
+       return result;
 }
 
-static
-expression_t *parse_reference(void)
+static expression_t *parse_offsetof(void)
 {
-       reference_expression_t *ref = allocate_ast_zero(sizeof(ref[0]));
-
-       ref->expression.type = EXPR_REFERENCE;
-       ref->symbol          = token.v.symbol;
+       eat(T___builtin_offsetof);
 
-       if(ref->symbol->declaration == NULL) {
-               parser_print_error_prefix();
-               fprintf(stderr, "unknown symbol '%s' found.\n", ref->symbol->string);
-       }
-       ref->declaration     = ref->symbol->declaration;
+       offsetof_expression_t *expression
+               = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type     = EXPR_OFFSETOF;
+       expression->expression.datatype = type_size_t;
 
-       next_token();
+       expect('(');
+       expression->type = parse_typename();
+       expect(',');
+       expression->designator = parse_designator();
+       expect(')');
 
-       return (expression_t*) ref;
+       return (expression_t*) expression;
 }
 
-static
-expression_t *parse_cast(void)
+static expression_t *parse_va_arg(void)
 {
-       unary_expression_t *cast = allocate_ast_zero(sizeof(cast[0]));
-
-       cast->expression.type            = EXPR_UNARY;
-       cast->type                       = UNEXPR_CAST;
-       cast->expression.source_position = token.source_position;
+       eat(T___builtin_va_arg);
 
-       type_t *type  = parse_typename();
+       va_arg_expression_t *expression = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type     = EXPR_VA_ARG;
 
+       expect('(');
+       expression->arg = parse_assignment_expression();
+       expect(',');
+       expression->expression.datatype = parse_typename();
        expect(')');
-       expression_t *value = parse_sub_expression(20);
-
-       cast->expression.datatype = type;
-       cast->value               = value;
 
-       return (expression_t*) cast;
+       return (expression_t*) expression;
 }
 
-static
-expression_t *parse_brace_expression(void)
+static expression_t *parse_builtin_symbol(void)
 {
-       eat('(');
+       builtin_symbol_expression_t *expression
+               = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type = EXPR_BUILTIN_SYMBOL;
 
-       declaration_t *declaration;
-       switch(token.type) {
-       TYPE_QUALIFIERS
-       TYPE_SPECIFIERS
-               return parse_cast();
-       case T_IDENTIFIER:
-               declaration = token.v.symbol->declaration;
-               if(declaration != NULL &&
-                               (declaration->storage_class & STORAGE_CLASS_TYPEDEF)) {
-                       return parse_cast();
-               }
-       }
+       /* TODO: set datatype */
 
-       expression_t *result = parse_expression();
-       expect(')');
+       expression->symbol = token.v.symbol;
 
-       return result;
+       next_token();
+
+       return (expression_t*) expression;
 }
 
-static
-expression_t *parse_primary_expression(void)
+static expression_t *parse_primary_expression(void)
 {
        switch(token.type) {
        case T_INTEGER:
                return parse_int_const();
+       case T_FLOATINGPOINT:
+               return parse_float_const();
        case T_STRING_LITERAL:
                return parse_string_const();
        case T_IDENTIFIER:
                return parse_reference();
+       case T___FUNCTION__:
+               return parse_function_keyword();
+       case T___PRETTY_FUNCTION__:
+               return parse_pretty_function_keyword();
+       case T___builtin_offsetof:
+               return parse_offsetof();
+       case T___builtin_va_arg:
+               return parse_va_arg();
+       case T___builtin_expect:
+       case T___builtin_va_start:
+       case T___builtin_va_end:
+               return parse_builtin_symbol();
+
        case '(':
                return parse_brace_expression();
        }
@@ -1531,12 +2273,16 @@ expression_t *parse_primary_expression(void)
        print_token(stderr, &token);
        fprintf(stderr, "\n");
        eat_statement();
-       return NULL;
+
+       expression_t *expression = allocate_ast_zero(sizeof(expression[0]));
+       expression->type     = EXPR_INVALID;
+       expression->datatype = type_void;
+
+       return expression;
 }
 
-static
-expression_t *parse_array_expression(unsigned precedence,
-                                     expression_t *array_ref)
+static expression_t *parse_array_expression(unsigned precedence,
+                                            expression_t *array_ref)
 {
        (void) precedence;
 
@@ -1545,75 +2291,79 @@ expression_t *parse_array_expression(unsigned precedence,
        array_access_expression_t *array_access
                = allocate_ast_zero(sizeof(array_access[0]));
 
-       array_access->expression.type = EXPR_ARRAY_ACCESS;
-       array_access->array_ref       = array_ref;
-       array_access->index           = parse_expression();
+       array_access->expression.type     = EXPR_ARRAY_ACCESS;
+       array_access->array_ref           = array_ref;
+       array_access->index               = parse_expression();
+
+       type_t *array_type = array_ref->datatype;
+       if(array_type != NULL) {
+               if(array_type->type == TYPE_POINTER) {
+                       pointer_type_t *pointer           = (pointer_type_t*) array_type;
+                       array_access->expression.datatype = pointer->points_to;
+               } else {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "array access on object with non-pointer type ");
+                       print_type(array_type);
+                       fprintf(stderr, "\n");
+               }
+       }
 
        if(token.type != ']') {
                parse_error_expected("Problem while parsing array access", ']', 0);
-               return NULL;
+               return (expression_t*) array_access;
        }
        next_token();
 
        return (expression_t*) array_access;
 }
 
-static
-type_t *get_expression_type(const expression_t *expression)
-{
-       (void) expression;
-       /* TODO */
-       return NULL;
-}
-
-static
-int is_type_specifier(const token_t *token)
+static bool is_declaration_specifier(const token_t *token,
+                                     bool only_type_specifiers)
 {
-       declaration_t *declaration;
-
        switch(token->type) {
                TYPE_SPECIFIERS
                        return 1;
                case T_IDENTIFIER:
-                       declaration = token->v.symbol->declaration;
-                       if(declaration == NULL)
-                               return 0;
-                       if(declaration->storage_class != STORAGE_CLASS_TYPEDEF)
+                       return is_typedef_symbol(token->v.symbol);
+               STORAGE_CLASSES
+               TYPE_QUALIFIERS
+                       if(only_type_specifiers)
                                return 0;
                        return 1;
+
                default:
                        return 0;
        }
 }
 
-static
-expression_t *parse_sizeof(unsigned precedence)
+static expression_t *parse_sizeof(unsigned precedence)
 {
        eat(T_sizeof);
 
        sizeof_expression_t *sizeof_expression
                = allocate_ast_zero(sizeof(sizeof_expression[0]));
-       sizeof_expression->expression.type = EXPR_SIZEOF;
+       sizeof_expression->expression.type     = EXPR_SIZEOF;
+       sizeof_expression->expression.datatype = type_size_t;
 
-       if(token.type == '(' && is_type_specifier(look_ahead(1))) {
+       if(token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
                next_token();
                sizeof_expression->type = parse_typename();
                expect(')');
        } else {
-               expression_t *expression = parse_sub_expression(precedence);
-               sizeof_expression->type  = get_expression_type(expression);
+               expression_t *expression           = parse_sub_expression(precedence);
+               sizeof_expression->type            = expression->datatype;
+               sizeof_expression->size_expression = expression;
        }
 
        return (expression_t*) sizeof_expression;
 }
 
-static
-expression_t *parse_select_expression(unsigned precedence,
-                                      expression_t *compound)
+static expression_t *parse_select_expression(unsigned precedence,
+                                             expression_t *compound)
 {
        (void) precedence;
 
-       assert(token.type == '.' || token.type == T_SELECT);
+       assert(token.type == '.' || token.type == T_MINUSGREATER);
        next_token();
 
        select_expression_t *select = allocate_ast_zero(sizeof(select[0]));
@@ -1621,10 +2371,11 @@ expression_t *parse_select_expression(unsigned precedence,
        select->expression.type = EXPR_SELECT;
        select->compound        = compound;
 
+       /* TODO: datatype */
+
        if(token.type != T_IDENTIFIER) {
-               parse_error_expected("Problem while parsing compound select",
-                                    T_IDENTIFIER, 0);
-               return NULL;
+               parse_error_expected("Problem while parsing select", T_IDENTIFIER, 0);
+               return (expression_t*) select;
        }
        select->symbol = token.v.symbol;
        next_token();
@@ -1632,15 +2383,31 @@ expression_t *parse_select_expression(unsigned precedence,
        return (expression_t*) select;
 }
 
-static
-expression_t *parse_call_expression(unsigned precedence,
-                                    expression_t *expression)
+static expression_t *parse_call_expression(unsigned precedence,
+                                           expression_t *expression)
 {
        (void) precedence;
        call_expression_t *call = allocate_ast_zero(sizeof(call[0]));
+       call->expression.type   = EXPR_CALL;
+       call->function          = expression;
 
-       call->expression.type            = EXPR_CALL;
-       call->method                     = expression;
+       function_type_t *function_type;
+       type_t          *type = expression->datatype;
+       if(type->type != TYPE_FUNCTION) {
+               /* TODO calling pointers to functions is ok */
+               parser_print_error_prefix();
+               fputs("called object '", stderr);
+               print_expression(expression);
+               fputs("' (type ", stderr);
+               print_type(type);
+               fputs("is not a function\n", stderr);
+
+               function_type             = NULL;
+               call->expression.datatype = NULL;
+       } else {
+               function_type             = (function_type_t*) type;
+               call->expression.datatype = function_type->result_type;
+       }
 
        /* parse arguments */
        eat('(');
@@ -1648,10 +2415,10 @@ expression_t *parse_call_expression(unsigned precedence,
        if(token.type != ')') {
                call_argument_t *last_argument = NULL;
 
-               while(1) {
+               while(true) {
                        call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
 
-                       argument->expression = parse_expression();
+                       argument->expression = parse_assignment_expression();
                        if(last_argument == NULL) {
                                call->arguments = argument;
                        } else {
@@ -1666,110 +2433,452 @@ expression_t *parse_call_expression(unsigned precedence,
        }
        expect(')');
 
+       if(function_type != NULL) {
+               function_parameter_t *parameter = function_type->parameters;
+               call_argument_t      *argument  = call->arguments;
+               for( ; parameter != NULL && argument != NULL;
+                               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);
+               }
+               /* too few parameters */
+               if(parameter != NULL) {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "too few arguments to function '");
+                       print_expression(expression);
+                       fprintf(stderr, "'\n");
+               } else if(argument != NULL) {
+                       /* too many parameters */
+                       if(!function_type->variadic
+                                       && !function_type->unspecified_parameters) {
+                               parser_print_error_prefix();
+                               fprintf(stderr, "too many arguments to function '");
+                               print_expression(expression);
+                               fprintf(stderr, "'\n");
+                       } else {
+                               /* do default promotion */
+                               for( ; argument != NULL; argument = argument->next) {
+                                       type_t *type = argument->expression->datatype;
+
+                                       if(is_type_integer(type)) {
+                                               type = promote_integer(type);
+                                       } else if(type == type_float) {
+                                               type = type_double;
+                                       }
+                                       argument->expression
+                                               = create_implicit_cast(argument->expression, type);
+                               }
+                       }
+               }
+       }
+
        return (expression_t*) call;
 }
 
-static
-expression_t *parse_conditional_expression(unsigned precedence,
-                                           expression_t *expression)
+static type_t *get_type_after_conversion(const type_t *type1,
+                                         const type_t *type2)
+{
+       /* TODO... */
+       (void) type2;
+       return (type_t*) type1;
+}
+
+static expression_t *parse_conditional_expression(unsigned precedence,
+                                                  expression_t *expression)
 {
        eat('?');
 
        conditional_expression_t *conditional
                = allocate_ast_zero(sizeof(conditional[0]));
+       conditional->expression.type = EXPR_CONDITIONAL;
        conditional->condition = expression;
 
+       /* 6.5.15.2 */
+       type_t *condition_type = conditional->condition->datatype;
+       if(condition_type != NULL) {
+               if(!is_type_scalar(condition_type)) {
+                       type_error("expected a scalar type", expression->source_position,
+                                  condition_type);
+               }
+       }
+
        conditional->true_expression = parse_expression();
        expect(':');
        conditional->false_expression = parse_sub_expression(precedence);
 
+       type_t *true_type  = conditional->true_expression->datatype;
+       if(true_type == NULL)
+               return (expression_t*) conditional;
+       type_t *false_type = conditional->false_expression->datatype;
+       if(false_type == NULL)
+               return (expression_t*) conditional;
+
+       /* 6.5.15.3 */
+       if(true_type == false_type) {
+               conditional->expression.datatype = true_type;
+       } else if(is_type_arithmetic(true_type) && is_type_arithmetic(false_type)) {
+               type_t *result = get_type_after_conversion(true_type, false_type);
+               /* TODO: create implicit convs if necessary */
+               conditional->expression.datatype = result;
+       } else if(true_type->type == TYPE_POINTER &&
+                 false_type->type == TYPE_POINTER &&
+                         true /* TODO compatible points_to types */) {
+               /* TODO */
+       } else if(/* (is_null_ptr_const(true_type) && false_type->type == TYPE_POINTER)
+              || (is_null_ptr_const(false_type) &&
+                  true_type->type == TYPE_POINTER) TODO*/ false) {
+               /* TODO */
+       } else if(/* 1 is pointer to object type, other is void* */ false) {
+               /* TODO */
+       } else {
+               type_error_incompatible("problem while parsing conditional",
+                                       expression->source_position, true_type,
+                                       false_type);
+       }
+
        return (expression_t*) conditional;
 }
 
-#define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type)     \
-static                                                                    \
-expression_t *parse_##unexpression_type(unsigned precedence)              \
-{                                                                         \
-       eat(token_type);                                                      \
-                                                                          \
-       unary_expression_t *unary_expression                                  \
-               = allocate_ast_zero(sizeof(unary_expression[0]));                 \
-       unary_expression->expression.type = EXPR_UNARY;                       \
-       unary_expression->type            = unexpression_type;                \
-       unary_expression->value           = parse_sub_expression(precedence); \
-                                                                          \
-       return (expression_t*) unary_expression;                              \
-}
-
-CREATE_UNARY_EXPRESSION_PARSER('-', UNEXPR_NEGATE)
-CREATE_UNARY_EXPRESSION_PARSER('+', UNEXPR_PLUS)
-CREATE_UNARY_EXPRESSION_PARSER('!', UNEXPR_NOT)
-CREATE_UNARY_EXPRESSION_PARSER('*', UNEXPR_DEREFERENCE)
-CREATE_UNARY_EXPRESSION_PARSER('&', UNEXPR_TAKE_ADDRESS)
-CREATE_UNARY_EXPRESSION_PARSER('~', UNEXPR_BITWISE_NEGATE)
-CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   UNEXPR_PREFIX_INCREMENT)
-CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, UNEXPR_PREFIX_DECREMENT)
-
-#define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type) \
-static                                                                        \
-expression_t *parse_##unexpression_type(unsigned precedence,                  \
-                                        expression_t *left)                   \
+static expression_t *parse_extension(unsigned precedence)
+{
+       eat(T___extension__);
+
+       /* TODO enable extensions */
+
+       return parse_sub_expression(precedence);
+}
+
+static type_t *get_unexpr_arithmetic_type(const expression_t *expression)
+{
+       /* TODO */
+       return expression->datatype;
+}
+
+static type_t *get_unexpr_dereference_type(const expression_t *expression)
+{
+       type_t *expression_type = expression->datatype;
+
+       if(expression_type->type == TYPE_POINTER) {
+               pointer_type_t *pointer_type = (pointer_type_t*) expression_type;
+               return pointer_type->points_to;
+       }
+       panic("deref TODO...");
+       return NULL;
+}
+
+static type_t *get_unexpr_take_addr_type(const expression_t *expression)
+{
+       type_t *type = expression->datatype;
+       return make_pointer_type(type, 0);
+}
+
+#define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, tfunc)   \
+static expression_t *parse_##unexpression_type(unsigned precedence)            \
+{                                                                              \
+       eat(token_type);                                                           \
+                                                                               \
+       unary_expression_t *unary_expression                                       \
+               = allocate_ast_zero(sizeof(unary_expression[0]));                      \
+       unary_expression->expression.type     = EXPR_UNARY;                        \
+       unary_expression->type                = unexpression_type;                 \
+       unary_expression->value               = parse_sub_expression(precedence);  \
+       unary_expression->expression.datatype = tfunc(unary_expression->value);    \
+                                                                               \
+       return (expression_t*) unary_expression;                                   \
+}
+
+CREATE_UNARY_EXPRESSION_PARSER('-', UNEXPR_NEGATE, get_unexpr_arithmetic_type)
+CREATE_UNARY_EXPRESSION_PARSER('+', UNEXPR_PLUS,   get_unexpr_arithmetic_type)
+CREATE_UNARY_EXPRESSION_PARSER('!', UNEXPR_NOT,    get_unexpr_arithmetic_type)
+CREATE_UNARY_EXPRESSION_PARSER('*', UNEXPR_DEREFERENCE,
+                               get_unexpr_dereference_type)
+CREATE_UNARY_EXPRESSION_PARSER('&', UNEXPR_TAKE_ADDRESS,
+                               get_unexpr_take_addr_type)
+CREATE_UNARY_EXPRESSION_PARSER('~', UNEXPR_BITWISE_NEGATE,
+                               get_unexpr_arithmetic_type)
+CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   UNEXPR_PREFIX_INCREMENT,
+                               get_unexpr_arithmetic_type)
+CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, UNEXPR_PREFIX_DECREMENT,
+                               get_unexpr_arithmetic_type)
+
+#define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
+                                               tfunc)                         \
+static expression_t *parse_##unexpression_type(unsigned precedence,           \
+                                               expression_t *left)            \
 {                                                                             \
        (void) precedence;                                                        \
        eat(token_type);                                                          \
                                                                               \
        unary_expression_t *unary_expression                                      \
                = allocate_ast_zero(sizeof(unary_expression[0]));                     \
-       unary_expression->expression.type = EXPR_UNARY;                           \
-       unary_expression->type            = unexpression_type;                    \
-       unary_expression->value           = left;                                 \
+       unary_expression->expression.type     = EXPR_UNARY;                       \
+       unary_expression->type                = unexpression_type;                \
+       unary_expression->value               = left;                             \
+       unary_expression->expression.datatype = tfunc(left);                      \
                                                                               \
        return (expression_t*) unary_expression;                                  \
 }
 
-CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,   UNEXPR_POSTFIX_INCREMENT)
-CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS, UNEXPR_POSTFIX_DECREMENT)
-
-#define CREATE_BINEXPR_PARSER(token_type, binexpression_type)    \
-static                                                           \
-expression_t *parse_##binexpression_type(unsigned precedence,    \
-                                         expression_t *left)     \
-{                                                                \
-       eat(token_type);                                             \
-                                                                 \
-       expression_t *right = parse_sub_expression(precedence);      \
-                                                                 \
-       binary_expression_t *binexpr                                 \
-               = allocate_ast_zero(sizeof(binexpr[0]));                 \
-       binexpr->expression.type            = EXPR_BINARY;           \
-       binexpr->type                       = binexpression_type;    \
-       binexpr->left                       = left;                  \
-       binexpr->right                      = right;                 \
-                                                                 \
-       return (expression_t*) binexpr;                              \
-}
-
-CREATE_BINEXPR_PARSER('*', BINEXPR_MUL)
-CREATE_BINEXPR_PARSER('/', BINEXPR_DIV)
-CREATE_BINEXPR_PARSER('+', BINEXPR_ADD)
-CREATE_BINEXPR_PARSER('-', BINEXPR_SUB)
-CREATE_BINEXPR_PARSER('<', BINEXPR_LESS)
-CREATE_BINEXPR_PARSER('>', BINEXPR_GREATER)
-CREATE_BINEXPR_PARSER('=', BINEXPR_ASSIGN)
-CREATE_BINEXPR_PARSER(T_EQUALEQUAL, BINEXPR_EQUAL)
-CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, BINEXPR_NOTEQUAL)
-CREATE_BINEXPR_PARSER(T_LESSEQUAL, BINEXPR_LESSEQUAL)
-CREATE_BINEXPR_PARSER(T_GREATEREQUAL, BINEXPR_GREATEREQUAL)
-CREATE_BINEXPR_PARSER('&', BINEXPR_BITWISE_AND)
-CREATE_BINEXPR_PARSER('|', BINEXPR_BITWISE_OR)
-CREATE_BINEXPR_PARSER('^', BINEXPR_BITWISE_XOR)
-CREATE_BINEXPR_PARSER(T_ANDAND, BINEXPR_LOGICAL_AND)
-CREATE_BINEXPR_PARSER(T_PIPEPIPE, BINEXPR_LOGICAL_OR)
-CREATE_BINEXPR_PARSER(T_LESSLESS, BINEXPR_SHIFTLEFT)
-CREATE_BINEXPR_PARSER(T_GREATERGREATER, BINEXPR_SHIFTRIGHT)
-
-static
-expression_t *parse_sub_expression(unsigned precedence)
+CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,   UNEXPR_POSTFIX_INCREMENT,
+                                       get_unexpr_arithmetic_type)
+CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS, UNEXPR_POSTFIX_DECREMENT,
+                                       get_unexpr_arithmetic_type)
+
+static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
+{
+       /* TODO: handle complex + imaginary types */
+
+       /* Â§ 6.3.1.8 Usual arithmetic conversions */
+       if(type_left == type_long_double || type_right == type_long_double) {
+               return type_long_double;
+       } else if(type_left == type_double || type_right == type_double) {
+               return type_double;
+       } else if(type_left == type_float || type_right == type_float) {
+               return type_float;
+       }
+
+       type_right = promote_integer(type_right);
+       type_left  = promote_integer(type_left);
+
+       if(type_left == type_right)
+               return type_left;
+
+       bool signed_left  = is_type_signed(type_left);
+       bool signed_right = is_type_signed(type_right);
+       if(get_rank(type_left) < get_rank(type_right)) {
+               if(signed_left == signed_right || !signed_right) {
+                       return type_right;
+               } else {
+                       return type_left;
+               }
+       } else {
+               if(signed_left == signed_right || !signed_left) {
+                       return type_left;
+               } else {
+                       return type_right;
+               }
+       }
+}
+
+static void semantic_binexpr_arithmetic(binary_expression_t *expression)
+{
+       expression_t *left       = expression->left;
+       expression_t *right      = expression->right;
+       type_t       *type_left  = skip_typeref(left->datatype);
+       type_t       *type_right = skip_typeref(right->datatype);
+
+       if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
+               /* TODO: improve error message */
+               parser_print_error_prefix();
+               fprintf(stderr, "operation needs arithmetic types\n");
+               return;
+       }
+
+       type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
+       expression->left  = create_implicit_cast(left, arithmetic_type);
+       expression->right = create_implicit_cast(right, arithmetic_type);
+       expression->expression.datatype = arithmetic_type;
+}
+
+static void semantic_add(binary_expression_t *expression)
+{
+       expression_t *left            = expression->left;
+       expression_t *right           = expression->right;
+       type_t       *orig_type_left  = left->datatype;
+       type_t       *orig_type_right = right->datatype;
+       type_t       *type_left       = skip_typeref(orig_type_left);
+       type_t       *type_right      = skip_typeref(orig_type_right);
+
+       /* Â§ 5.6.5 */
+       if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
+               type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
+               expression->left  = create_implicit_cast(left, arithmetic_type);
+               expression->right = create_implicit_cast(right, arithmetic_type);
+               expression->expression.datatype = arithmetic_type;
+               return;
+       } else if(type_left->type == TYPE_POINTER && is_type_integer(type_right)) {
+               expression->expression.datatype = type_left;
+       } else if(type_right->type == TYPE_POINTER && is_type_integer(type_left)) {
+               expression->expression.datatype = type_right;
+       } else {
+               parser_print_error_prefix();
+               fprintf(stderr, "invalid operands to binary + (");
+               print_type(orig_type_left);
+               fprintf(stderr, ", ");
+               print_type(orig_type_right);
+               fprintf(stderr, ")\n");
+       }
+}
+
+static void semantic_sub(binary_expression_t *expression)
+{
+       expression_t *left            = expression->left;
+       expression_t *right           = expression->right;
+       type_t       *orig_type_left  = left->datatype;
+       type_t       *orig_type_right = right->datatype;
+       type_t       *type_left       = skip_typeref(orig_type_left);
+       type_t       *type_right      = skip_typeref(orig_type_right);
+
+       /* Â§ 5.6.5 */
+       if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
+               type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
+               expression->left  = create_implicit_cast(left, arithmetic_type);
+               expression->right = create_implicit_cast(right, arithmetic_type);
+               expression->expression.datatype = arithmetic_type;
+               return;
+       } else if(type_left->type == TYPE_POINTER && is_type_integer(type_right)) {
+               expression->expression.datatype = type_left;
+       } else if(type_left->type == TYPE_POINTER &&
+                       type_right->type == TYPE_POINTER) {
+               if(!pointers_compatible(type_left, type_right)) {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "pointers to incompatible objects to binary - (");
+                       print_type(orig_type_left);
+                       fprintf(stderr, ", ");
+                       print_type(orig_type_right);
+                       fprintf(stderr, ")\n");
+               } else {
+                       expression->expression.datatype = type_ptrdiff_t;
+               }
+       } else {
+               parser_print_error_prefix();
+               fprintf(stderr, "invalid operands to binary - (");
+               print_type(orig_type_left);
+               fprintf(stderr, ", ");
+               print_type(orig_type_right);
+               fprintf(stderr, ")\n");
+       }
+}
+
+static void semantic_comparison(binary_expression_t *expression)
+{
+       expression_t *left       = expression->left;
+       expression_t *right      = expression->right;
+       type_t       *type_left  = left->datatype;
+       type_t       *type_right = right->datatype;
+
+       /* TODO non-arithmetic types */
+       if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
+               type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
+               expression->left  = create_implicit_cast(left, arithmetic_type);
+               expression->right = create_implicit_cast(right, arithmetic_type);
+               expression->expression.datatype = arithmetic_type;
+       }
+       expression->expression.datatype = type_int;
+}
+
+static void semantic_arithmetic_assign(binary_expression_t *expression)
+{
+       expression_t *left       = expression->left;
+       expression_t *right      = expression->right;
+       type_t       *type_left  = left->datatype;
+       type_t       *type_right = right->datatype;
+
+       if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
+               /* TODO: improve error message */
+               parser_print_error_prefix();
+               fprintf(stderr, "operation needs arithmetic types\n");
+               return;
+       }
+
+       /* combined instructions are tricky. We can't create an implicit cast on
+        * the left side, because we need the uncasted form for the store.
+        * The ast2firm pass has to know that left_type must be right_type
+        * for the arithmeitc operation and create a cast by itself */
+       type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
+       expression->right       = create_implicit_cast(right, arithmetic_type);
+       expression->expression.datatype = type_left;
+}
+
+static void semantic_logical_op(binary_expression_t *expression)
+{
+       /* TODO */
+       expression->expression.datatype = type_int;
+}
+
+static void semantic_binexpr_assign(binary_expression_t *expression)
+{
+       expression_t *left       = expression->left;
+       type_t       *type_left  = left->datatype;
+
+       semantic_assign(type_left, &expression->right, "assignment");
+
+       expression->expression.datatype = type_left;
+}
+
+static void semantic_comma(binary_expression_t *expression)
+{
+       expression->expression.datatype = expression->right->datatype;
+}
+
+#define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr) \
+static expression_t *parse_##binexpression_type(unsigned precedence,     \
+                                                expression_t *left)      \
+{                                                                        \
+       eat(token_type);                                                     \
+                                                                         \
+       expression_t *right = parse_sub_expression(precedence + lr);         \
+                                                                         \
+       binary_expression_t *binexpr                                         \
+               = allocate_ast_zero(sizeof(binexpr[0]));                         \
+       binexpr->expression.type     = EXPR_BINARY;                          \
+       binexpr->type                = binexpression_type;                   \
+       binexpr->left                = left;                                 \
+       binexpr->right               = right;                                \
+       sfunc(binexpr);                                                      \
+                                                                         \
+       return (expression_t*) binexpr;                                      \
+}
+
+CREATE_BINEXPR_PARSER(',', BINEXPR_COMMA,          semantic_comma, 1)
+CREATE_BINEXPR_PARSER('*', BINEXPR_MUL,            semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER('/', BINEXPR_DIV,            semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER('%', BINEXPR_MOD,            semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER('+', BINEXPR_ADD,            semantic_add, 1)
+CREATE_BINEXPR_PARSER('-', BINEXPR_SUB,            semantic_sub, 1)
+CREATE_BINEXPR_PARSER('<', BINEXPR_LESS,           semantic_comparison, 1)
+CREATE_BINEXPR_PARSER('>', BINEXPR_GREATER,        semantic_comparison, 1)
+CREATE_BINEXPR_PARSER('=', BINEXPR_ASSIGN,         semantic_binexpr_assign, 0)
+CREATE_BINEXPR_PARSER(T_EQUALEQUAL, BINEXPR_EQUAL, semantic_comparison, 1)
+CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, BINEXPR_NOTEQUAL,
+                      semantic_comparison, 1)
+CREATE_BINEXPR_PARSER(T_LESSEQUAL, BINEXPR_LESSEQUAL, semantic_comparison, 1)
+CREATE_BINEXPR_PARSER(T_GREATEREQUAL, BINEXPR_GREATEREQUAL,
+                      semantic_comparison, 1)
+CREATE_BINEXPR_PARSER('&', BINEXPR_BITWISE_AND,    semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER('|', BINEXPR_BITWISE_OR,     semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER('^', BINEXPR_BITWISE_XOR,    semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER(T_ANDAND, BINEXPR_LOGICAL_AND,  semantic_logical_op, 1)
+CREATE_BINEXPR_PARSER(T_PIPEPIPE, BINEXPR_LOGICAL_OR, semantic_logical_op, 1)
+/* TODO shift has a bit special semantic */
+CREATE_BINEXPR_PARSER(T_LESSLESS, BINEXPR_SHIFTLEFT,
+                      semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER(T_GREATERGREATER, BINEXPR_SHIFTRIGHT,
+                      semantic_binexpr_arithmetic, 1)
+CREATE_BINEXPR_PARSER(T_PLUSEQUAL, BINEXPR_ADD_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_MINUSEQUAL, BINEXPR_SUB_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, BINEXPR_MUL_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_SLASHEQUAL, BINEXPR_DIV_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, BINEXPR_MOD_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, BINEXPR_SHIFTLEFT_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, BINEXPR_SHIFTRIGHT_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_ANDEQUAL, BINEXPR_BITWISE_AND_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_PIPEEQUAL, BINEXPR_BITWISE_OR_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+CREATE_BINEXPR_PARSER(T_CARETEQUAL, BINEXPR_BITWISE_XOR_ASSIGN,
+                      semantic_arithmetic_assign, 0)
+
+static expression_t *parse_sub_expression(unsigned precedence)
 {
        if(token.type < 0) {
                return expected_expression_error();
@@ -1785,10 +2894,10 @@ expression_t *parse_sub_expression(unsigned precedence)
        } else {
                left = parse_primary_expression();
        }
-       if(left != NULL)
-               left->source_position = source_position;
+       assert(left != NULL);
+       left->source_position = source_position;
 
-       while(1) {
+       while(true) {
                if(token.type < 0) {
                        return expected_expression_error();
                }
@@ -1800,23 +2909,24 @@ expression_t *parse_sub_expression(unsigned precedence)
                        break;
 
                left = parser->infix_parser(parser->infix_precedence, left);
-               if(left != NULL)
-                       left->source_position = source_position;
+
+               assert(left != NULL);
+               assert(left->type != EXPR_INVALID);
+               left->source_position = source_position;
        }
 
        return left;
 }
 
-static
-expression_t *parse_expression(void)
+static expression_t *parse_expression(void)
 {
        return parse_sub_expression(1);
 }
 
 
 
-void register_expression_parser(parse_expression_function parser,
-                                int token_type, unsigned precedence)
+static void register_expression_parser(parse_expression_function parser,
+                                       int token_type, unsigned precedence)
 {
        expression_parser_function_t *entry = &expression_parsers[token_type];
 
@@ -1830,8 +2940,9 @@ void register_expression_parser(parse_expression_function parser,
        entry->precedence = precedence;
 }
 
-void register_expression_infix_parser(parse_expression_infix_function parser,
-                                      int token_type, unsigned precedence)
+static void register_expression_infix_parser(
+               parse_expression_infix_function parser, int token_type,
+               unsigned precedence)
 {
        expression_parser_function_t *entry = &expression_parsers[token_type];
 
@@ -1846,39 +2957,58 @@ void register_expression_infix_parser(parse_expression_infix_function parser,
        entry->infix_precedence = precedence;
 }
 
-static
-void init_expression_parsers(void)
+static void init_expression_parsers(void)
 {
        memset(&expression_parsers, 0, sizeof(expression_parsers));
 
-       register_expression_infix_parser(parse_BINEXPR_MUL,       '*', 16);
-       register_expression_infix_parser(parse_BINEXPR_DIV,       '/', 16);
-       register_expression_infix_parser(parse_BINEXPR_SHIFTLEFT,
-                                  T_LESSLESS, 16);
+       register_expression_infix_parser(parse_BINEXPR_MUL,         '*',        16);
+       register_expression_infix_parser(parse_BINEXPR_DIV,         '/',        16);
+       register_expression_infix_parser(parse_BINEXPR_MOD,         '%',        16);
+       register_expression_infix_parser(parse_BINEXPR_SHIFTLEFT,   T_LESSLESS, 16);
        register_expression_infix_parser(parse_BINEXPR_SHIFTRIGHT,
-                                  T_GREATERGREATER, 16);
-       register_expression_infix_parser(parse_BINEXPR_ADD,       '+', 15);
-       register_expression_infix_parser(parse_BINEXPR_SUB,       '-', 15);
-       register_expression_infix_parser(parse_BINEXPR_LESS,      '<', 14);
-       register_expression_infix_parser(parse_BINEXPR_GREATER,   '>', 14);
-       register_expression_infix_parser(parse_BINEXPR_LESSEQUAL, T_LESSEQUAL, 14);
+                                                             T_GREATERGREATER, 16);
+       register_expression_infix_parser(parse_BINEXPR_ADD,         '+',        15);
+       register_expression_infix_parser(parse_BINEXPR_SUB,         '-',        15);
+       register_expression_infix_parser(parse_BINEXPR_LESS,        '<',        14);
+       register_expression_infix_parser(parse_BINEXPR_GREATER,     '>',        14);
+       register_expression_infix_parser(parse_BINEXPR_LESSEQUAL, T_LESSEQUAL,  14);
        register_expression_infix_parser(parse_BINEXPR_GREATEREQUAL,
-                                  T_GREATEREQUAL, 14);
+                                                               T_GREATEREQUAL, 14);
        register_expression_infix_parser(parse_BINEXPR_EQUAL,     T_EQUALEQUAL, 13);
        register_expression_infix_parser(parse_BINEXPR_NOTEQUAL,
-                                        T_EXCLAMATIONMARKEQUAL, 13);
+                                                       T_EXCLAMATIONMARKEQUAL, 13);
        register_expression_infix_parser(parse_BINEXPR_BITWISE_AND, '&',        12);
        register_expression_infix_parser(parse_BINEXPR_BITWISE_XOR, '^',        11);
        register_expression_infix_parser(parse_BINEXPR_BITWISE_OR,  '|',        10);
        register_expression_infix_parser(parse_BINEXPR_LOGICAL_AND, T_ANDAND,    9);
        register_expression_infix_parser(parse_BINEXPR_LOGICAL_OR,  T_PIPEPIPE,  8);
        register_expression_infix_parser(parse_conditional_expression, '?',      7);
-       register_expression_infix_parser(parse_BINEXPR_ASSIGN,      T_EQUAL,     2);
+       register_expression_infix_parser(parse_BINEXPR_ASSIGN,      '=',         2);
+       register_expression_infix_parser(parse_BINEXPR_ADD_ASSIGN, T_PLUSEQUAL,  2);
+       register_expression_infix_parser(parse_BINEXPR_SUB_ASSIGN, T_MINUSEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_MUL_ASSIGN,
+                                                               T_ASTERISKEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_DIV_ASSIGN, T_SLASHEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_MOD_ASSIGN,
+                                                                T_PERCENTEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_SHIFTLEFT_ASSIGN,
+                                                               T_LESSLESSEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_SHIFTRIGHT_ASSIGN,
+                                                         T_GREATERGREATEREQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_BITWISE_AND_ASSIGN,
+                                                                    T_ANDEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_BITWISE_OR_ASSIGN,
+                                                                   T_PIPEEQUAL, 2);
+       register_expression_infix_parser(parse_BINEXPR_BITWISE_XOR_ASSIGN,
+                                                                  T_CARETEQUAL, 2);
+
+       register_expression_infix_parser(parse_BINEXPR_COMMA,       ',',         1);
 
        register_expression_infix_parser(parse_array_expression,        '[',    30);
        register_expression_infix_parser(parse_call_expression,         '(',    30);
        register_expression_infix_parser(parse_select_expression,       '.',    30);
-       register_expression_infix_parser(parse_select_expression,  T_SELECT,    30);
+       register_expression_infix_parser(parse_select_expression,
+                                                               T_MINUSGREATER, 30);
        register_expression_infix_parser(parse_UNEXPR_POSTFIX_INCREMENT,
                                         T_PLUSPLUS, 30);
        register_expression_infix_parser(parse_UNEXPR_POSTFIX_DECREMENT,
@@ -1893,32 +3023,40 @@ void init_expression_parsers(void)
        register_expression_parser(parse_UNEXPR_PREFIX_INCREMENT, T_PLUSPLUS,   25);
        register_expression_parser(parse_UNEXPR_PREFIX_DECREMENT, T_MINUSMINUS, 25);
        register_expression_parser(parse_sizeof,                  T_sizeof,     25);
+       register_expression_parser(parse_extension,            T___extension__, 25);
 }
 
 
-static
-statement_t *parse_case_statement(void)
+static statement_t *parse_case_statement(void)
 {
        eat(T_case);
-       parse_expression();
+       case_label_statement_t *label = allocate_ast_zero(sizeof(label[0]));
+       label->statement.type            = STATEMENT_CASE_LABEL;
+       label->statement.source_position = token.source_position;
+
+       label->expression = parse_expression();
+
        expect(':');
-       parse_statement();
+       label->statement.next = parse_statement();
 
-       return NULL;
+       return (statement_t*) label;
 }
 
-static
-statement_t *parse_default_statement(void)
+static statement_t *parse_default_statement(void)
 {
        eat(T_default);
+
+       case_label_statement_t *label = allocate_ast_zero(sizeof(label[0]));
+       label->statement.type            = STATEMENT_CASE_LABEL;
+       label->statement.source_position = token.source_position;
+
        expect(':');
-       parse_statement();
+       label->statement.next = parse_statement();
 
-       return NULL;
+       return (statement_t*) label;
 }
 
-static
-statement_t *parse_label_statement(void)
+static statement_t *parse_label_statement(void)
 {
        eat(T_IDENTIFIER);
        expect(':');
@@ -1927,13 +3065,13 @@ statement_t *parse_label_statement(void)
        return NULL;
 }
 
-static
-statement_t *parse_if(void)
+static statement_t *parse_if(void)
 {
        eat(T_if);
 
        if_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
-       statement->statement.type = STATEMENT_IF;
+       statement->statement.type            = STATEMENT_IF;
+       statement->statement.source_position = token.source_position;
 
        expect('(');
        statement->condition = parse_expression();
@@ -1948,68 +3086,99 @@ statement_t *parse_if(void)
        return (statement_t*) statement;
 }
 
-static
-statement_t *parse_switch(void)
+static statement_t *parse_switch(void)
 {
        eat(T_switch);
+
+       switch_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_SWITCH;
+       statement->statement.source_position = token.source_position;
+
        expect('(');
-       parse_expression();
+       statement->expression = parse_expression();
        expect(')');
-       parse_statement();
+       statement->body = parse_statement();
 
-       return NULL;
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_while(void)
+static statement_t *parse_while(void)
 {
        eat(T_while);
+
+       while_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_WHILE;
+       statement->statement.source_position = token.source_position;
+
        expect('(');
-       parse_expression();
+       statement->condition = parse_expression();
        expect(')');
-       parse_statement();
+       statement->body = parse_statement();
 
-       return NULL;
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_do(void)
+static statement_t *parse_do(void)
 {
        eat(T_do);
-       parse_statement();
+
+       do_while_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_DO_WHILE;
+       statement->statement.source_position = token.source_position;
+
+       statement->body = parse_statement();
        expect(T_while);
        expect('(');
-       parse_expression();
+       statement->condition = parse_expression();
        expect(')');
+       expect(';');
 
-       return NULL;
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_for(void)
+static statement_t *parse_for(void)
 {
        eat(T_for);
+
+       for_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_FOR;
+       statement->statement.source_position = token.source_position;
+
        expect('(');
+
+       int         top          = environment_top();
+       context_t  *last_context = context;
+       set_context(&statement->context);
+
        if(token.type != ';') {
-               /* TODO not correct... this could also be a declaration */
-               parse_expression();
+               if(is_declaration_specifier(&token, false)) {
+                       parse_declaration();
+               } else {
+                       statement->initialisation = parse_expression();
+                       expect(';');
+               }
+       } else {
+               expect(';');
        }
-       expect(';');
+
        if(token.type != ';') {
-               parse_expression();
+               statement->condition = parse_expression();
        }
        expect(';');
        if(token.type != ')') {
-               parse_expression();
+               statement->step = parse_expression();
        }
        expect(')');
-       parse_statement();
+       statement->body = parse_statement();
 
-       return NULL;
+       assert(context == &statement->context);
+       set_context(last_context);
+       environment_pop_to(top);
+
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_goto(void)
+static statement_t *parse_goto(void)
 {
        eat(T_goto);
        expect(T_IDENTIFIER);
@@ -2018,8 +3187,7 @@ statement_t *parse_goto(void)
        return NULL;
 }
 
-static
-statement_t *parse_continue(void)
+static statement_t *parse_continue(void)
 {
        eat(T_continue);
        expect(';');
@@ -2031,48 +3199,99 @@ statement_t *parse_continue(void)
        return statement;
 }
 
-static
-statement_t *parse_break(void)
+static statement_t *parse_break(void)
 {
        eat(T_break);
        expect(';');
 
-       return NULL;
+       statement_t *statement     = allocate_ast_zero(sizeof(statement[0]));
+       statement->source_position = token.source_position;
+       statement->type            = STATEMENT_BREAK;
+
+       return statement;
 }
 
-static
-statement_t *parse_return(void)
+static statement_t *parse_return(void)
 {
        eat(T_return);
 
        return_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
-       statement->statement.type = STATEMENT_RETURN;
+
+       statement->statement.type            = STATEMENT_RETURN;
+       statement->statement.source_position = token.source_position;
+
+       assert(current_function->type->type == TYPE_FUNCTION);
+       function_type_t *function_type = (function_type_t*) current_function->type;
+       type_t          *return_type   = function_type->result_type;
+
+       expression_t *return_value;
        if(token.type != ';') {
-               statement->return_value = parse_expression();
+               return_value = parse_expression();
+
+               if(return_type == type_void && return_value->datatype != type_void) {
+                       parse_warning("'return' with a value, in function returning void");
+                       return_value = NULL;
+               } else {
+                       semantic_assign(return_type, &return_value, "'return'");
+               }
+       } else {
+               return_value = NULL;
+               if(return_type != type_void) {
+                       parse_warning("'return' without value, in function returning "
+                                     "non-void");
+               }
        }
+       statement->return_value = return_value;
+
        expect(';');
 
        return (statement_t*) statement;
 }
 
-static
-statement_t *parse_declaration_statement(void)
+static statement_t *parse_declaration_statement(void)
 {
-       parse_declaration();
-       return NULL;
+       declaration_t *before = last_declaration;
+
+       declaration_statement_t *statement
+               = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_DECLARATION;
+       statement->statement.source_position = token.source_position;
+
+       declaration_specifiers_t specifiers;
+       memset(&specifiers, 0, sizeof(specifiers));
+       parse_declaration_specifiers(&specifiers);
+
+       if(token.type == ';') {
+               eat(';');
+       } else {
+               parse_init_declarators(&specifiers);
+       }
+
+       if(before == NULL) {
+               statement->declarations_begin = context->declarations;
+       } else {
+               statement->declarations_begin = before->next;
+       }
+       statement->declarations_end = last_declaration;
+
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_expression_statement(void)
+static statement_t *parse_expression_statement(void)
 {
-       parse_expression();
-       return NULL;
+       expression_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+       statement->statement.type            = STATEMENT_EXPRESSION;
+       statement->statement.source_position = token.source_position;
+
+       statement->expression = parse_expression();
+
+       expect(';');
+
+       return (statement_t*) statement;
 }
 
-static
-statement_t *parse_statement(void)
+static statement_t *parse_statement(void)
 {
-       declaration_t *declaration;
        statement_t   *statement = NULL;
 
        /* declaration or statement */
@@ -2136,9 +3355,7 @@ statement_t *parse_statement(void)
                        break;
                }
 
-               declaration = token.v.symbol->declaration;
-               if(declaration != NULL &&
-                               declaration->storage_class == STORAGE_CLASS_TYPEDEF) {
+               if(is_typedef_symbol(token.v.symbol)) {
                        statement = parse_declaration_statement();
                        break;
                }
@@ -2146,6 +3363,15 @@ statement_t *parse_statement(void)
                statement = parse_expression_statement();
                break;
 
+       case T___extension__:
+               /* this can be a prefix to a declaration or an expression statement */
+               /* we simply eat it now and parse the rest with tail recursion */
+               do {
+                       next_token();
+               } while(token.type == T___extension__);
+               statement = parse_statement();
+               break;
+
        DECLARATION_START
                statement = parse_declaration_statement();
                break;
@@ -2155,17 +3381,19 @@ statement_t *parse_statement(void)
                break;
        }
 
+       assert(statement == NULL || statement->source_position.input_name != NULL);
+
        return statement;
 }
 
-static
-statement_t *parse_compound_statement(void)
+static statement_t *parse_compound_statement(void)
 {
        eat('{');
 
        compound_statement_t *compound_statement
                = allocate_ast_zero(sizeof(compound_statement[0]));
-       compound_statement->statement.type = STATEMENT_COMPOUND;
+       compound_statement->statement.type            = STATEMENT_COMPOUND;
+       compound_statement->statement.source_position = token.source_position;
 
        int        top          = environment_top();
        context_t *last_context = context;
@@ -2175,12 +3403,18 @@ statement_t *parse_compound_statement(void)
 
        while(token.type != '}' && token.type != T_EOF) {
                statement_t *statement = parse_statement();
+               if(statement == NULL)
+                       continue;
 
                if(last_statement != NULL) {
                        last_statement->next = statement;
                } else {
                        compound_statement->statements = statement;
                }
+
+               while(statement->next != NULL)
+                       statement = statement->next;
+
                last_statement = statement;
        }
 
@@ -2193,11 +3427,13 @@ statement_t *parse_compound_statement(void)
        return (statement_t*) compound_statement;
 }
 
-static
-translation_unit_t *parse_translation_unit(void)
+static translation_unit_t *parse_translation_unit(void)
 {
        translation_unit_t *unit = allocate_ast_zero(sizeof(unit[0]));
 
+       assert(global_context == NULL);
+       global_context = &unit->context;
+
        assert(context == NULL);
        set_context(&unit->context);
 
@@ -2209,15 +3445,19 @@ translation_unit_t *parse_translation_unit(void)
        context          = NULL;
        last_declaration = NULL;
 
+       assert(global_context == &unit->context);
+       global_context = NULL;
+
        return unit;
 }
 
 translation_unit_t *parse(void)
 {
-       obstack_init(&environment_obstack);
-       environment_stack = NEW_ARR_F(environment_entry_t*, 0);
+       environment_stack = NEW_ARR_F(stack_entry_t, 0);
+       found_error       = false;
 
        type_set_output(stderr);
+       ast_set_output(stderr);
 
        lookahead_bufpos = 0;
        for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
@@ -2226,7 +3466,9 @@ translation_unit_t *parse(void)
        translation_unit_t *unit = parse_translation_unit();
 
        DEL_ARR_F(environment_stack);
-       obstack_free(&environment_obstack, NULL);
+
+       if(found_error)
+               return NULL;
 
        return unit;
 }
@@ -2235,6 +3477,17 @@ void init_parser(void)
 {
        init_expression_parsers();
        obstack_init(&temp_obst);
+
+       type_int         = make_atomic_type(ATOMIC_TYPE_INT, 0);
+       type_uint        = make_atomic_type(ATOMIC_TYPE_UINT, 0);
+       type_long_double = make_atomic_type(ATOMIC_TYPE_LONG_DOUBLE, 0);
+       type_double      = make_atomic_type(ATOMIC_TYPE_DOUBLE, 0);
+       type_float       = make_atomic_type(ATOMIC_TYPE_FLOAT, 0);
+       type_size_t      = make_atomic_type(ATOMIC_TYPE_ULONG, 0);
+       type_ptrdiff_t   = make_atomic_type(ATOMIC_TYPE_LONG, 0);
+       type_const_char  = make_atomic_type(ATOMIC_TYPE_CHAR, TYPE_QUALIFIER_CONST);
+       type_void        = make_atomic_type(ATOMIC_TYPE_VOID, 0);
+       type_string      = make_pointer_type(type_const_char, 0);
 }
 
 void exit_parser(void)