more work on local variable support
[cparser] / parser.c
index f823725..fdb85bd 100644 (file)
--- a/parser.c
+++ b/parser.c
 
 #include <assert.h>
 #include <stdarg.h>
+#include <stdbool.h>
 
-#include "lexer_t.h"
+#include "parser.h"
+#include "lexer.h"
 #include "token_t.h"
 #include "type_t.h"
+#include "type_hash.h"
 #include "ast_t.h"
 #include "adt/bitfiddle.h"
 #include "adt/error.h"
+#include "adt/array.h"
+
+//#define PRINT_TOKENS
+//#define ABORT_ON_ERROR
+#define MAX_LOOKAHEAD 2
+//#define STRICT_C99
+
+typedef struct {
+       declaration_t *old_declaration;
+       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 struct obstack        temp_obst;
+
+static type_t               *type_int        = NULL;
+static type_t               *type_double     = 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 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:
 
-#define PRINT_TOKENS
+#ifdef PROVIDE_COMPLEX
+#define COMPLEX_SPECIFIERS  \
+       case T__Complex:
+#else
+#define COMPLEX_SPECIFIERS
+#endif
 
-static token_t token;
+#ifdef PROVIDE_IMAGINARY
+#define IMAGINARY_SPECIFIERS \
+       case T__Imaginary:
+#else
+#define IMAGINARY_SPECIFIERS
+#endif
 
-static inline
-void *allocate_ast_zero(size_t size)
+#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
+
+#define DECLARATION_START   \
+       STORAGE_CLASSES         \
+       TYPE_QUALIFIERS         \
+       TYPE_SPECIFIERS
+
+#define TYPENAME_START      \
+       TYPE_QUALIFIERS         \
+       TYPE_SPECIFIERS
+
+static inline void *allocate_ast_zero(size_t size)
 {
        void *res = allocate_ast(size);
        memset(res, 0, size);
        return res;
 }
 
-static inline
-void next_token(void)
+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)
+{
+       return ARR_LEN(environment_stack);
+}
+
+
+
+static inline void next_token(void)
 {
-       lexer_next_token(&token);
+       token                              = lookahead_buffer[lookahead_bufpos];
+       lookahead_buffer[lookahead_bufpos] = lexer_token;
+       lexer_next_token();
+
+       lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 
 #ifdef PRINT_TOKENS
        print_token(stderr, &token);
@@ -33,30 +145,58 @@ void next_token(void)
 #endif
 }
 
-static inline
-void eat(token_type_t type)
+static inline const token_t *look_ahead(int num)
 {
-       assert(token.type == type);
-       next_token();
+       assert(num > 0 && num <= MAX_LOOKAHEAD);
+       int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
+       return & lookahead_buffer[pos];
+}
+
+#define eat(token_type)  do { assert(token.type == token_type); next_token(); } while(0)
+
+static void error(void)
+{
+#ifdef ABORT_ON_ERROR
+       abort();
+#endif
 }
 
-void parser_print_error_prefix(void)
+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);
+    fputs(": ", stderr);
 }
 
-static
-void parse_error(const char *message)
+static void parser_print_error_prefix_pos(
+               const source_position_t source_position)
+{
+       parser_print_prefix_pos(source_position);
+       fputs("error: ", stderr);
+       error();
+}
+
+static void parser_print_error_prefix(void)
+{
+       parser_print_prefix_pos(token.source_position);
+       error();
+}
+
+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, ...)
+__attribute__((unused))
+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;
@@ -85,162 +225,837 @@ void parse_error_expected(const char *message, ...)
        fprintf(stderr, "\n");
 }
 
-static
-void eat_until_semi(void)
+static void eat_block(void)
+{
+       if(token.type == '{')
+               next_token();
+
+       while(token.type != '}') {
+               if(token.type == T_EOF)
+                       return;
+               if(token.type == '{') {
+                       eat_block();
+                       continue;
+               }
+               next_token();
+       }
+       eat('}');
+}
+
+static void eat_statement(void)
 {
        while(token.type != ';') {
+               if(token.type == T_EOF)
+                       return;
+               if(token.type == '}')
+                       return;
+               if(token.type == '{') {
+                       eat_block();
+                       continue;
+               }
+               next_token();
+       }
+       eat(';');
+}
+
+static void eat_brace(void)
+{
+       if(token.type == '(')
                next_token();
+
+       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;
+               }
+               next_token();
        }
-       next_token();
+       eat(')');
 }
 
 #define expect(expected)                           \
     if(UNLIKELY(token.type != (expected))) {       \
         parse_error_expected(NULL, (expected), 0); \
-        eat_until_semi();                          \
+        eat_statement();                           \
         return NULL;                               \
     }                                              \
     next_token();
 
-typedef enum {
-       SPECIFIER_SIGNED    = 1 << 0,
-       SPECIFIER_UNSIGNED  = 1 << 1,
-       SPECIFIER_LONG      = 1 << 2,
-       SPECIFIER_INT       = 1 << 3,
-       SPECIFIER_DOUBLE    = 1 << 4,
-       SPECIFIER_CHAR      = 1 << 5,
-       SPECIFIER_SHORT     = 1 << 6,
-       SPECIFIER_LONG_LONG = 1 << 7,
-       SPECIFIER_FLOAT     = 1 << 8,
-       SPECIFIER_BOOL      = 1 << 9,
-       SPECIFIER_VOID      = 1 << 10,
-#ifdef PROVIDE_COMPLEX
-       SPECIFIER_COMPLEX   = 1 << 11,
-#endif
-#ifdef PROVIDE_IMAGINARY
-       SPECIFIER_IMAGINARY = 1 << 12,
-#endif
-} specifiers_t;
+#define expect_void(expected)                      \
+    if(UNLIKELY(token.type != (expected))) {       \
+        parse_error_expected(NULL, (expected), 0); \
+        eat_statement();                           \
+        return;                                    \
+    }                                              \
+    next_token();
+
+static void set_context(context_t *new_context)
+{
+       context = new_context;
+
+       last_declaration = new_context->declarations;
+       if(last_declaration != NULL) {
+               while(last_declaration->next != NULL) {
+                       last_declaration = last_declaration->next;
+               }
+       }
+}
+
+/**
+ * called when we find a 2nd declarator for an identifier we already have a
+ * declarator for
+ */
+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 declaration_t *environment_push(declaration_t *declaration)
+{
+       symbol_t    *symbol    = declaration->symbol;
+       namespace_t  namespace = declaration->namespace;
+       assert(declaration->source_position.input_name != NULL);
+
+       /* 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;
+       }
+
+       /* remember old declaration */
+       stack_entry_t entry;
+       entry.symbol          = symbol;
+       entry.old_declaration = symbol->declaration;
+       entry.namespace       = namespace;
+       ARR_APP1(environment_stack, entry);
+
+       /* 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 declaration;
+}
+
+/**
+ * pops symbols from the environment stack until @p new_top is the top element
+ */
+static void environment_pop_to(size_t new_top)
+{
+       size_t top = ARR_LEN(environment_stack);
+       size_t i;
+
+       assert(new_top <= top);
+       if(new_top == top)
+               return;
+
+       for(i = top; i > new_top; --i) {
+               stack_entry_t *entry = & environment_stack[i - 1];
+
+               declaration_t *old_declaration = entry->old_declaration;
+               symbol_t      *symbol          = entry->symbol;
+               namespace_t    namespace       = entry->namespace;
+
+               /* 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);
+}
 
-typedef enum {
-       TYPE_QUALIFIER_CONST    = 1 << 0,
-       TYPE_QUALIFIER_RESTRICT = 1 << 1,
-       TYPE_QUALIFIER_VOLATILE = 1 << 2,
-       TYPE_QUALIFIER_INLINE   = 1 << 3,
-} type_qualifier_t;
 
-typedef enum {
-       STORAGE_CLASS_NONE,
-       STORAGE_CLASS_TYPEDEF,
-       STORAGE_CLASS_EXTERN,
-       STORAGE_CLASS_STATIC,
-       STORAGE_CLASS_AUTO,
-       STORAGE_CLASS_REGISTER
-} storage_class_t;
+
+static expression_t *parse_constant_expression(void)
+{
+       /* start parsing at precedence 7 (conditional expression) */
+       return parse_sub_expression(7);
+}
+
+static expression_t *parse_assignment_expression(void)
+{
+       /* start parsing at precedence 2 (assignment expression) */
+       return parse_sub_expression(2);
+}
+
+static void parse_compound_type_entries(void);
+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;
 struct declaration_specifiers_t {
        storage_class_t  storage_class;
-       int              type_qualifiers;
+       type_t          *type;
 };
 
-static
-void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
+static const char *parse_string_literals(void)
 {
-       type_type_t        type_type       = TYPE_INVALID;
-       atomic_type_type_t atomic_type     = ATOMIC_TYPE_INVALID;
-       unsigned           type_specifiers = 0;
+       assert(token.type == T_STRING_LITERAL);
+       const char *result = token.v.string;
 
-       while(1) {
+       next_token();
+
+       while(token.type == T_STRING_LITERAL) {
+               result = concat_strings(result, token.v.string);
+               next_token();
+       }
+
+       return result;
+}
+
+static void parse_attributes(void)
+{
+       while(true) {
                switch(token.type) {
+               case T___attribute__:
+                       next_token();
 
-               /* storage class */
-#define MATCH_STORAGE_CLASS(token, class)                                \
-               case token:                                                      \
-                       if(specifiers->storage_class != STORAGE_CLASS_NONE) {        \
-                               parse_error("multiple storage classes in declaration "   \
-                                           "specifiers");                               \
-                       }                                                            \
-                       specifiers->storage_class = class;                           \
-                       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;
+               }
+       }
 
-               MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
-               MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
-               MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
-               MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
-               MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
+attributes_finished:
+       ;
+}
 
-               /* type qualifiers */
-#define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
-               case token:                                                     \
-                       specifiers->type_qualifiers |= qualifier;                   \
-                       next_token();                                               \
-                       break;
+static designator_t *parse_designation(void)
+{
+       if(token.type != '[' && token.type != '.')
+               return NULL;
 
-               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);
+       designator_t *result = NULL;
+       designator_t *last   = NULL;
 
-               /* type specifiers */
-#define MATCH_SPECIFIER(token, specifier, name)                         \
-               case token:                                                     \
-                       next_token();                                               \
-                       if(type_specifiers & specifier) {                           \
-                               parse_error("multiple " name " type specifiers given"); \
-                       } else {                                                    \
-                               type_specifiers |= specifier;                           \
-                       }                                                           \
+       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;
-
-               MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void")
-               MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char")
-               MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short")
-               MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int")
-               MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float")
-               MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double")
-               MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed")
-               MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned")
-               MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool")
-#ifdef PROVIDE_COMPLEX
-               MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex")
-#endif
-#ifdef PROVIDE_IMAGINARY
-               MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary")
-#endif
-               case T_long:
+               case '.':
+                       designator = allocate_ast_zero(sizeof(designator[0]));
                        next_token();
-                       if(type_specifiers & SPECIFIER_LONG_LONG) {
-                               parse_error("too many long type specifiers given");
-                       } else if(type_specifiers & SPECIFIER_LONG) {
-                               type_specifiers |= SPECIFIER_LONG_LONG;
-                       } else {
-                               type_specifiers |= SPECIFIER_LONG;
+                       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;
+               }
 
-               case T_struct:
-               case T_enum:
-                       /* TODO */
-                       assert(0);
+               assert(designator != NULL);
+               if(last != NULL) {
+                       last->next = designator;
+               } else {
+                       result = designator;
+               }
+               last = designator;
+       }
+}
+
+static initializer_t *parse_initializer_list(void);
+
+static initializer_t *parse_initializer(void)
+{
+       designator_t *designator = parse_designation();
+
+       initializer_t *result;
+       if(token.type == '{') {
+               result = parse_initializer_list();
+       } else {
+               result          = allocate_ast_zero(sizeof(result[0]));
+               result->type    = INITIALIZER_VALUE;
+               result->v.value = parse_assignment_expression();
+       }
+       result->designator = designator;
+
+       return result;
+}
+
+static initializer_t *parse_initializer_list(void)
+{
+       eat('{');
+
+       initializer_t *result = allocate_ast_zero(sizeof(result[0]));
+       result->type = INITIALIZER_LIST;
+
+       initializer_t *last = NULL;
+       while(1) {
+               initializer_t *initializer = parse_initializer();
+               if(last != NULL) {
+                       last->next = initializer;
+               } else {
+                       result->v.list = initializer;
+               }
+               last = initializer;
+
+               if(token.type == '}')
                        break;
 
-               /* function specifier */
-               default:
-                       return;;
+               if(token.type != ',') {
+                       parse_error_expected("problem while parsing initializer list",
+                                            ',', '}', 0);
+                       eat_block();
+                       return result;
                }
-       }
+               eat(',');
 
-       if(type_type == TYPE_INVALID) {
-               /* match valid basic types */
-               switch(type_specifiers) {
-               case SPECIFIER_VOID:
-                       atomic_type = ATOMIC_TYPE_VOID;
+               if(token.type == '}')
                        break;
-               case SPECIFIER_CHAR:
+       }
+
+       expect('}');
+
+       return result;
+}
+
+static declaration_t *parse_compound_type_specifier(bool is_struct)
+{
+       if(is_struct) {
+               eat(T_struct);
+       } else {
+               eat(T_union);
+       }
+
+       symbol_t      *symbol      = NULL;
+       declaration_t *declaration = NULL;
+
+       if(token.type == T_IDENTIFIER) {
+               symbol = token.v.symbol;
+               next_token();
+
+               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 specifier",
+                                            T_IDENTIFIER, '{', 0);
+               } else {
+                       parse_error_expected("problem while parsing union type specifier",
+                                            T_IDENTIFIER, '{', 0);
+               }
+
+               return NULL;
+       }
+
+       if(declaration == NULL) {
+               declaration = allocate_type_zero(sizeof(declaration[0]));
+
+               if(is_struct) {
+                       declaration->namespace = NAMESPACE_STRUCT;
+               } else {
+                       declaration->namespace = NAMESPACE_UNION;
+               }
+               declaration->source_position = token.source_position;
+               declaration->symbol          = symbol;
+       }
+
+       if(token.type == '{') {
+               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);
+                       declaration->context.declarations = NULL;
+               }
+               record_declaration(declaration);
+               declaration->init.is_defined = true;
+
+               int         top          = environment_top();
+               context_t  *last_context = context;
+               set_context(& declaration->context);
+
+               parse_compound_type_entries();
+               parse_attributes();
+
+               assert(context == & declaration->context);
+               set_context(last_context);
+               environment_pop_to(top);
+       }
+
+       return declaration;
+}
+
+static void parse_enum_entries(void)
+{
+       eat('{');
+
+       if(token.type == '}') {
+               next_token();
+               parse_error("empty enum not allowed");
+               return;
+       }
+
+       do {
+               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;
+               }
+               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->init.initializer = parse_initializer();
+               }
+
+               record_declaration(entry);
+
+               if(token.type != ',')
+                       break;
+               next_token();
+       } while(token.type != '}');
+
+       expect_void('}');
+}
+
+static declaration_t *parse_enum_specifier(void)
+{
+       eat(T_enum);
+
+       declaration_t *declaration;
+       symbol_t      *symbol;
+
+       if(token.type == T_IDENTIFIER) {
+               symbol = token.v.symbol;
+               next_token();
+
+               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 {
+               declaration = NULL;
+               symbol      = NULL;
+       }
+
+       if(declaration == NULL) {
+               declaration = allocate_type_zero(sizeof(declaration[0]));
+
+               declaration->namespace       = NAMESPACE_ENUM;
+               declaration->source_position = token.source_position;
+               declaration->symbol          = symbol;
+       }
+
+       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;
+
+               parse_enum_entries();
+               parse_attributes();
+       }
+
+       return declaration;
+}
+
+/**
+ * if a symbol is a typedef to another type, return true
+ */
+static bool is_typedef_symbol(symbol_t *symbol)
+{
+       declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
+       if(declaration == NULL
+                       || declaration->storage_class != STORAGE_CLASS_TYPEDEF)
+               return false;
+
+       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();
+               } 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;
+       }
+
+       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 {
+       SPECIFIER_SIGNED    = 1 << 0,
+       SPECIFIER_UNSIGNED  = 1 << 1,
+       SPECIFIER_LONG      = 1 << 2,
+       SPECIFIER_INT       = 1 << 3,
+       SPECIFIER_DOUBLE    = 1 << 4,
+       SPECIFIER_CHAR      = 1 << 5,
+       SPECIFIER_SHORT     = 1 << 6,
+       SPECIFIER_LONG_LONG = 1 << 7,
+       SPECIFIER_FLOAT     = 1 << 8,
+       SPECIFIER_BOOL      = 1 << 9,
+       SPECIFIER_VOID      = 1 << 10,
+#ifdef PROVIDE_COMPLEX
+       SPECIFIER_COMPLEX   = 1 << 11,
+#endif
+#ifdef PROVIDE_IMAGINARY
+       SPECIFIER_IMAGINARY = 1 << 12,
+#endif
+} specifiers_t;
+
+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;
+
+       return (type_t*) type;
+}
+
+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)
+{
+       type_t        *type            = NULL;
+       unsigned       type_qualifiers = 0;
+       unsigned       type_specifiers = 0;
+       int            newtype         = 0;
+
+       while(true) {
+               switch(token.type) {
+
+               /* storage class */
+#define MATCH_STORAGE_CLASS(token, class)                                \
+               case token:                                                      \
+                       if(specifiers->storage_class != STORAGE_CLASS_NONE) {        \
+                               parse_error("multiple storage classes in declaration "   \
+                                           "specifiers");                               \
+                       }                                                            \
+                       specifiers->storage_class = class;                           \
+                       next_token();                                                \
+                       break;
+
+               MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
+               MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
+               MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
+               MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
+               MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
+
+               /* type qualifiers */
+#define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
+               case token:                                                     \
+                       type_qualifiers |= qualifier;                               \
+                       next_token();                                               \
+                       break;
+
+               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);
+
+               case T___extension__:
+                       /* TODO */
+                       next_token();
+                       break;
+
+               /* type specifiers */
+#define MATCH_SPECIFIER(token, specifier, name)                         \
+               case token:                                                     \
+                       next_token();                                               \
+                       if(type_specifiers & specifier) {                           \
+                               parse_error("multiple " name " type specifiers given"); \
+                       } else {                                                    \
+                               type_specifiers |= specifier;                           \
+                       }                                                           \
+                       break;
+
+               MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void")
+               MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char")
+               MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short")
+               MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int")
+               MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float")
+               MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double")
+               MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed")
+               MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned")
+               MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool")
+#ifdef PROVIDE_COMPLEX
+               MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex")
+#endif
+#ifdef PROVIDE_IMAGINARY
+               MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary")
+#endif
+               case T_long:
+                       next_token();
+                       if(type_specifiers & SPECIFIER_LONG_LONG) {
+                               parse_error("multiple type specifiers given");
+                       } else if(type_specifiers & SPECIFIER_LONG) {
+                               type_specifiers |= SPECIFIER_LONG_LONG;
+                       } else {
+                               type_specifiers |= SPECIFIER_LONG;
+                       }
+                       break;
+
+               /* 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: {
+                       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: {
+                       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);
+                       next_token();
+                       break;
+
+               case T___attribute__:
+                       /* TODO */
+                       parse_attributes();
+                       break;
+
+               case T_IDENTIFIER: {
+                       type_t *typedef_type = get_typedef_type(token.v.symbol);
+
+                       if(typedef_type == NULL)
+                               goto finish_specifiers;
+
+                       next_token();
+                       type = typedef_type;
+                       break;
+               }
+
+               /* function specifier */
+               default:
+                       goto finish_specifiers;
+               }
+       }
+
+finish_specifiers:
+
+       if(type == NULL) {
+               atomic_type_type_t atomic_type;
+
+               /* match valid basic types */
+               switch(type_specifiers) {
+               case SPECIFIER_VOID:
+                       atomic_type = ATOMIC_TYPE_VOID;
+                       break;
+               case SPECIFIER_CHAR:
                        atomic_type = ATOMIC_TYPE_CHAR;
                        break;
                case SPECIFIER_SIGNED | SPECIFIER_CHAR:
@@ -278,14 +1093,16 @@ void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
                        atomic_type = ATOMIC_TYPE_ULONG;
                        break;
-               case SPECIFIER_LONG_LONG:
-               case SPECIFIER_SIGNED | SPECIFIER_LONG_LONG:
-               case SPECIFIER_LONG_LONG | SPECIFIER_INT:
-               case SPECIFIER_SIGNED | SPECIFIER_LONG_LONG | SPECIFIER_INT:
+               case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
+               case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
+               case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
+               case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
+                       | SPECIFIER_INT:
                        atomic_type = ATOMIC_TYPE_LONGLONG;
                        break;
-               case SPECIFIER_UNSIGNED | SPECIFIER_LONG_LONG:
-               case SPECIFIER_UNSIGNED | SPECIFIER_LONG_LONG | SPECIFIER_INT:
+               case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
+               case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
+                       | SPECIFIER_INT:
                        atomic_type = ATOMIC_TYPE_ULONGLONG;
                        break;
                case SPECIFIER_FLOAT:
@@ -325,7 +1142,13 @@ void parse_declaration_specifiers(declaration_specifiers_t *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");
@@ -334,107 +1157,597 @@ void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                        } else {
                                parse_error("multiple datatypes in declaration");
                        }
+                       atomic_type = ATOMIC_TYPE_INVALID;
                }
+
+               atomic_type_t *atype = allocate_type_zero(sizeof(atype[0]));
+               atype->type.type     = TYPE_ATOMIC;
+               atype->atype         = atomic_type;
+               newtype              = 1;
+
+               type = (type_t*) atype;
        } else {
                if(type_specifiers != 0) {
                        parse_error("multiple datatypes in declaration");
                }
        }
-}
 
-typedef struct declarator_t declarator_t;
-struct declarator_t {
-       /* pointer stuff... */
-       symbol_t     *symbol;
-
-       declarator_t *next;
-};
+       type->qualifiers = type_qualifiers;
 
-declarator_t *parse_declarator(void)
-{
-       while(token.type == '*') {
-               /* pointer */
-               next_token();
-               //parse_type_qualifiers();
+       type_t *result = typehash_insert(type);
+       if(newtype && result != (type_t*) type) {
+               free_type(type);
        }
 
-       declarator_t *declarator;
+       specifiers->type = result;
+}
 
-       switch(token.type) {
-       case T_IDENTIFIER:
-               declarator = allocate_ast_zero(sizeof(declarator[0]));
-               declarator->symbol = token.v.symbol;
-               next_token();
-               return declarator;
-       case '(':
-               next_token();
-               declarator = parse_declarator();
-               expect(')')
-               return declarator;
-       default:
-               parse_error("problem while parsing declarator");
-       }
+static type_qualifier_t parse_type_qualifiers(void)
+{
+       type_qualifier_t type_qualifiers = 0;
 
-       if(token.type == '(') {
-               next_token();
+       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);
 
-               /* parse parameter-type-list or identifier-list */
+               default:
+                       return type_qualifiers;
+               }
+       }
+}
 
-               expect(')');
-       } else if(token.type == '[') {
+static void parse_identifier_list(void)
+{
+       while(true) {
+               if(token.type != T_IDENTIFIER) {
+                       parse_error_expected("problem while parsing parameter identifier "
+                                            "list", T_IDENTIFIER, 0);
+                       return;
+               }
+               next_token();
+               if(token.type != ',')
+                       break;
                next_token();
+       }
+}
+
+static declaration_t *parse_parameter(void)
+{
+       declaration_specifiers_t specifiers;
+       memset(&specifiers, 0, sizeof(specifiers));
 
-               /* multiple type qualifiers, and static */
+       parse_declaration_specifiers(&specifiers);
 
-               /* assignment_expression or '*' or nothing */
+       declaration_t *declaration = parse_declarator(specifiers.storage_class,
+                                                     specifiers.type, 1);
 
-               expect(']');
+       /* TODO check declaration constraints for parameters */
+       if(declaration->storage_class == STORAGE_CLASS_TYPEDEF) {
+               parse_error("typedef not allowed in parameter list");
        }
 
-       return declarator;
+       return declaration;
 }
 
-void parse_init_declarators(const declaration_specifiers_t *specifiers)
+static declaration_t *parse_parameters(function_type_t *type)
 {
-       (void) specifiers;
-       declarator_t *declarator = parse_declarator();
-       if(token.type == '=') {
+       if(token.type == T_IDENTIFIER) {
+               symbol_t      *symbol = token.v.symbol;
+               if(!is_typedef_symbol(symbol)) {
+                       /* TODO */
+                       parse_identifier_list();
+                       return NULL;
+               }
+       }
+
+       if(token.type == ')') {
+               type->unspecified_parameters = 1;
+               return NULL;
+       }
+       if(token.type == T_void && look_ahead(1)->type == ')') {
+               next_token();
+               return NULL;
+       }
+
+       declaration_t        *declarations = NULL;
+       declaration_t        *declaration;
+       declaration_t        *last_declaration = NULL;
+       function_parameter_t *parameter;
+       function_parameter_t *last_parameter = NULL;
+
+       while(true) {
+               switch(token.type) {
+               case T_DOTDOTDOT:
+                       next_token();
+                       type->variadic = 1;
+                       return declarations;
+
+               case T_IDENTIFIER:
+               case T___extension__:
+               DECLARATION_START
+                       declaration = parse_parameter();
+
+                       parameter       = allocate_type_zero(sizeof(parameter[0]));
+                       parameter->type = declaration->type;
+
+                       if(last_parameter != NULL) {
+                               last_declaration->next = declaration;
+                               last_parameter->next   = parameter;
+                       } else {
+                               type->parameters = parameter;
+                               declarations     = declaration;
+                       }
+                       last_parameter   = parameter;
+                       last_declaration = declaration;
+                       break;
+
+               default:
+                       return declarations;
+               }
+               if(token.type != ',')
+                       return declarations;
                next_token();
-               //parse_initialize();
        }
-       (void) declarator;
 }
 
-typedef struct declaration_t declaration_t;
-struct declaration_t {
-       declaration_specifiers_t  specifiers;
-       declaration_t            *declarators;
+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;
 };
 
-void parse_declaration(void)
+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 construct_type_t *parse_inner_declarator(declaration_t *declaration,
+               int may_be_abstract)
 {
+       construct_type_t *result = NULL;
+       construct_type_t *last   = NULL;
+
+       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) {
+                       parse_error("no identifier expected in typename");
+               } else {
+                       declaration->symbol          = token.v.symbol;
+                       declaration->source_position = token.source_position;
+               }
+               next_token();
+               break;
+       case '(':
+               next_token();
+               inner_types = parse_inner_declarator(declaration, may_be_abstract);
+               expect(')');
+               break;
+       default:
+               if(may_be_abstract)
+                       break;
+               parse_error_expected("problem while parsing declarator", T_IDENTIFIER,
+                                    '(', 0);
+       }
+
+       while(true) {
+               construct_type_t *type;
+               switch(token.type) {
+               case '(':
+                       type = parse_function_declarator(declaration);
+                       break;
+               case '[':
+                       type = parse_array_declarator();
+                       break;
+               default:
+                       goto declarator_finished;
+               }
+
+               if(last != NULL) {
+                       last->next = type;
+               } else {
+                       result = type;
+               }
+               last = type;
+       }
+
+declarator_finished:
+       parse_attributes();
+
+       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(construct_type_t *construct_list,
+                                         type_t *type)
+{
+       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;
+
+               switch(iter->type) {
+               case CONSTRUCT_FUNCTION:
+                       construct_function_type = (construct_function_type_t*) iter;
+                       function_type           = construct_function_type->function_type;
+
+                       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;
+               }
+
+               type_t *hashed_type = typehash_insert((type_t*) type);
+               if(hashed_type != type) {
+                       free_type(type);
+                       type = hashed_type;
+               }
+       }
+
+       return type;
+}
+
+static declaration_t *parse_declarator(storage_class_t storage_class,
+               type_t *type, int may_be_abstract)
+{
+       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(construct_type != NULL) {
+               obstack_free(&temp_obst, construct_type);
+       }
+
+       return declaration;
+}
+
+static type_t *parse_abstract_declarator(type_t *base_type)
+{
+       construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
+
+       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)
+{
+       assert(context != NULL);
+
+       symbol_t *symbol = declaration->symbol;
+       if(symbol != NULL) {
+               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;
+       }
+       last_declaration = declaration;
+
+       return 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",
+               declaration->symbol->string);
+       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)
+{
+       while(true) {
+               declaration_t *ndeclaration
+                       = parse_declarator(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 (no function type) */
+
+                       if(declaration->init.initializer != NULL) {
+                               parser_error_multiple_definition(declaration, ndeclaration);
+                       }
+
+                       ndeclaration->init.initializer = parse_initializer();
+               } else if(token.type == '{') {
+                       if(declaration->type->type != TYPE_FUNCTION) {
+                               parser_print_error_prefix();
+                               fprintf(stderr, "Declarator ");
+                               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->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;
+                       set_context(&declaration->context);
+
+                       /* push function parameters */
+                       declaration_t *parameter = declaration->context.declarations;
+                       for( ; parameter != NULL; parameter = parameter->next) {
+                               environment_push(parameter);
+                       }
+
+                       statement_t *statement = parse_compound_statement();
+
+                       assert(context == &declaration->context);
+                       set_context(last_context);
+                       environment_pop_to(top);
+
+                       declaration->init.statement = statement;
+                       return;
+               }
+
+               if(token.type != ',')
+                       break;
+               next_token();
+       }
+       expect_void(';');
+}
+
+static void parse_struct_declarators(const declaration_specifiers_t *specifiers)
+{
+       while(1) {
+               if(token.type == ':') {
+                       next_token();
+                       parse_constant_expression();
+                       /* TODO (bitfields) */
+               } else {
+                       declaration_t *declaration
+                               = parse_declarator(specifiers->storage_class,
+                                                  specifiers->type, 1);
+
+                       /* TODO: check constraints for struct declarations */
+                       /* TODO: check for doubled fields */
+                       record_declaration(declaration);
+
+                       if(token.type == ':') {
+                               next_token();
+                               parse_constant_expression();
+                               /* TODO (bitfields) */
+                       }
+               }
+
+               if(token.type != ',')
+                       break;
+               next_token();
+       }
+       expect_void(';');
+}
+
+static void parse_compound_type_entries(void)
+{
+       eat('{');
+
+       while(token.type != '}' && token.type != T_EOF) {
+               declaration_specifiers_t specifiers;
+               memset(&specifiers, 0, sizeof(specifiers));
+               parse_declaration_specifiers(&specifiers);
+
+               parse_struct_declarators(&specifiers);
+       }
+       if(token.type == T_EOF) {
+               parse_error("unexpected error while parsing struct");
+       }
+       next_token();
+}
+
+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);
 }
 
-#if 0
-namespace_t *parse(FILE *in, const char *input_name)
+static type_t *parse_typename(void)
 {
-       namespace_t *namespace = parse_namespace();
+       declaration_specifiers_t specifiers;
+       memset(&specifiers, 0, sizeof(specifiers));
+       parse_declaration_specifiers(&specifiers);
+       if(specifiers.storage_class != STORAGE_CLASS_NONE) {
+               /* TODO: improve error message, user does probably not know what a
+                * storage class is...
+                */
+               parse_error("typename may not have a storage class");
+       }
+
+       type_t *result = parse_abstract_declarator(specifiers.type);
 
-       return namespace;
+       return result;
 }
-#endif
 
 
 
-static
-expression_t *parse_sub_expression(unsigned precedence);
-static
-expression_t *parse_expression(void);
 
 typedef expression_t* (*parse_expression_function) (unsigned precedence);
 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
@@ -450,8 +1763,7 @@ 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 ");
@@ -462,80 +1774,370 @@ expression_t *expected_expression_error(void)
        expression->type = EXPR_INVALID;
        next_token();
 
-       return expression;
+       return expression;
+}
+
+static expression_t *parse_string_const(void)
+{
+       string_literal_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
+
+       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_float_const(void)
+{
+       const_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
+
+       cnst->expression.type     = EXPR_CONST;
+       cnst->expression.datatype = type_double;
+       cnst->v.float_value       = token.v.floatvalue;
+
+       next_token();
+
+       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));
+
+       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 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_string_const(void)
+static expression_t *parse_offsetof(void)
 {
-       string_literal_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
+       eat(T___builtin_offsetof);
 
-       cnst->expression.type = EXPR_STRING_LITERAL;
-       cnst->value           = token.v.string;
+       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*) cnst;
+       return (expression_t*) expression;
 }
 
-static
-expression_t *parse_int_const(void)
+static expression_t *parse_va_arg(void)
 {
-       const_t *cnst = allocate_ast_zero(sizeof(cnst[0]));
+       eat(T___builtin_va_arg);
 
-       cnst->expression.type = EXPR_CONST;
-       cnst->value           = token.v.intvalue;
+       va_arg_expression_t *expression = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type     = EXPR_VA_ARG;
 
-       next_token();
+       expect('(');
+       expression->arg = parse_assignment_expression();
+       expect(',');
+       expression->expression.datatype = parse_typename();
+       expect(')');
 
-       return (expression_t*) cnst;
+       return (expression_t*) expression;
 }
 
-static
-expression_t *parse_reference(void)
+static expression_t *parse_builtin_symbol(void)
 {
-       reference_expression_t *ref = allocate_ast_zero(sizeof(ref[0]));
+       builtin_symbol_expression_t *expression
+               = allocate_ast_zero(sizeof(expression[0]));
+       expression->expression.type = EXPR_BUILTIN_SYMBOL;
 
-       ref->expression.type            = EXPR_REFERENCE;
-       ref->symbol                     = token.v.symbol;
+       /* TODO: set datatype */
 
-       next_token();
-
-       return (expression_t*) ref;
-}
+       expression->symbol = token.v.symbol;
 
-static
-expression_t *parse_brace_expression(void)
-{
-       eat('(');
-
-       expression_t *result = parse_expression();
-       expect(')');
+       next_token();
 
-       return result;
+       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();
        }
 
-       /* TODO: error message */
-       return NULL;
+       parser_print_error_prefix();
+       fprintf(stderr, "unexpected token ");
+       print_token(stderr, &token);
+       fprintf(stderr, "\n");
+       eat_statement();
+
+       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;
 
@@ -544,36 +2146,79 @@ 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
-expression_t *parse_sizeof(unsigned precedence)
+static bool is_declaration_specifier(const token_t *token,
+                                     bool only_type_specifiers)
+{
+       switch(token->type) {
+               TYPE_SPECIFIERS
+                       return 1;
+               case T_IDENTIFIER:
+                       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)
 {
-       (void) precedence;
        eat(T_sizeof);
-       /* TODO... */
 
-       return NULL;
+       sizeof_expression_t *sizeof_expression
+               = allocate_ast_zero(sizeof(sizeof_expression[0]));
+       sizeof_expression->expression.type     = EXPR_SIZEOF;
+       sizeof_expression->expression.datatype = type_size_t;
+
+       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            = 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]));
@@ -581,10 +2226,11 @@ 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();
@@ -592,15 +2238,14 @@ 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->method                     = expression;
+       call->expression.type     = EXPR_CALL;
+       call->function            = expression;
 
        /* parse arguments */
        eat('(');
@@ -608,10 +2253,10 @@ 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 {
@@ -626,91 +2271,294 @@ expression_t *parse_call_expression(unsigned precedence,
        }
        expect(')');
 
+       type_t *type = expression->datatype;
+       if(type != NULL) {
+               /* we can call pointer to function */
+               if(type->type == TYPE_POINTER) {
+                       pointer_type_t *pointer = (pointer_type_t*) type;
+                       type = pointer->points_to;
+               }
+
+               if(type == NULL || type->type != TYPE_FUNCTION) {
+                       parser_print_error_prefix();
+                       fprintf(stderr, "expected a function type for call but found "
+                               "type ");
+                       print_type(expression->datatype);
+                       fprintf(stderr, "\n");
+               } else {
+                       function_type_t *function_type = (function_type_t*) type;
+                       call->expression.datatype      = function_type->result_type;
+               }
+       }
+
        return (expression_t*) call;
 }
 
-#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 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 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;
+}
+
+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)
+{
+       (void) expression;
+       /* 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_SLASHEQUAL, 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_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 *get_binexpr_int_type(const expression_t *left,
+                                    const expression_t *right)
+{
+       (void) left;
+       (void) right;
+       return type_int;
+}
+
+static type_t *get_binexpr_arithmetic_type(const expression_t *left,
+                                            const expression_t *right)
+{
+       (void) right;
+       return left->datatype;
+}
+
+static type_t *get_binexpr_arithmetic_assign_type(const expression_t *left,
+                                                  const expression_t *right)
+{
+       (void) right;
+       /* TODO */
+       return left->datatype;
+}
+
+static type_t *get_binexpr_right_type(const expression_t *left,
+                                       const expression_t *right)
+{
+       (void) left;
+       return right->datatype;
+}
+
+#define CREATE_BINEXPR_PARSER(token_type, binexpression_type, tfunc)    \
+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;                               \
+       binexpr->expression.datatype = tfunc(left, right);                  \
+                                                                        \
+       return (expression_t*) binexpr;                                     \
+}
+
+CREATE_BINEXPR_PARSER(',', BINEXPR_COMMA,   get_binexpr_right_type)
+CREATE_BINEXPR_PARSER('*', BINEXPR_MUL,     get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('/', BINEXPR_DIV,     get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('%', BINEXPR_MOD,     get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('+', BINEXPR_ADD,     get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('-', BINEXPR_SUB,     get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('<', BINEXPR_LESS,    get_binexpr_int_type)
+CREATE_BINEXPR_PARSER('>', BINEXPR_GREATER, get_binexpr_int_type)
+CREATE_BINEXPR_PARSER('=', BINEXPR_ASSIGN,  get_binexpr_right_type)
+CREATE_BINEXPR_PARSER(T_EQUALEQUAL, BINEXPR_EQUAL,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, BINEXPR_NOTEQUAL,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER(T_LESSEQUAL, BINEXPR_LESSEQUAL,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER(T_GREATEREQUAL, BINEXPR_GREATEREQUAL,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER('&', BINEXPR_BITWISE_AND, get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('|', BINEXPR_BITWISE_OR,  get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER('^', BINEXPR_BITWISE_XOR, get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER(T_ANDAND, BINEXPR_LOGICAL_AND,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER(T_PIPEPIPE, BINEXPR_LOGICAL_OR,
+                      get_binexpr_int_type)
+CREATE_BINEXPR_PARSER(T_LESSLESS, BINEXPR_SHIFTLEFT,
+                      get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER(T_GREATERGREATER, BINEXPR_SHIFTRIGHT,
+                      get_binexpr_arithmetic_type)
+CREATE_BINEXPR_PARSER(T_PLUSEQUAL, BINEXPR_ADD_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_MINUSEQUAL, BINEXPR_SUB_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, BINEXPR_MUL_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_SLASHEQUAL, BINEXPR_DIV_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, BINEXPR_MOD_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, BINEXPR_SHIFTLEFT_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, BINEXPR_SHIFTRIGHT_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_ANDEQUAL, BINEXPR_BITWISE_AND_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_PIPEEQUAL, BINEXPR_BITWISE_OR_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+CREATE_BINEXPR_PARSER(T_CARETEQUAL, BINEXPR_BITWISE_XOR_ASSIGN,
+                      get_binexpr_arithmetic_assign_type)
+
+static expression_t *parse_sub_expression(unsigned precedence)
 {
        if(token.type < 0) {
                return expected_expression_error();
@@ -718,7 +2566,7 @@ expression_t *parse_sub_expression(unsigned precedence)
 
        expression_parser_function_t *parser
                = &expression_parsers[token.type];
-       source_position_t             source_position = source_position;
+       source_position_t             source_position = token.source_position;
        expression_t                 *left;
 
        if(parser->parser != NULL) {
@@ -726,10 +2574,10 @@ 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();
                }
@@ -741,23 +2589,24 @@ 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];
 
@@ -771,8 +2620,9 @@ 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];
 
@@ -787,36 +2637,58 @@ 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_ASSIGN,      T_EQUAL,     2);
+       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,      '=',         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,
@@ -831,125 +2703,162 @@ 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_compound_statement(void);
-
-static
-statement_t *parse_statement(void);
-
-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(';');
+       expect(':');
        parse_statement();
 
        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.source_position = token.source_position;
+
        expect('(');
-       parse_expression();
+       statement->condition = parse_expression();
        expect(')');
 
-       parse_statement();
+       statement->true_statement = parse_statement();
        if(token.type == T_else) {
                next_token();
-               parse_statement();
+               statement->false_statement = parse_statement();
        }
 
-       return NULL;
+       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);
@@ -958,38 +2867,91 @@ statement_t *parse_goto(void)
        return NULL;
 }
 
-static
-statement_t *parse_continue(void)
+static statement_t *parse_continue(void)
 {
        eat(T_continue);
        expect(';');
 
-       return NULL;
+       statement_t *statement     = allocate_ast_zero(sizeof(statement[0]));
+       statement->source_position = token.source_position;
+       statement->type            = STATEMENT_CONTINUE;
+
+       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);
-       parse_expression();
+
+       return_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
+
+       statement->statement.type            = STATEMENT_RETURN;
+       statement->statement.source_position = token.source_position;
+       if(token.type != ';') {
+               statement->return_value = parse_expression();
+       }
        expect(';');
 
-       return NULL;
+       return (statement_t*) statement;
+}
+
+static statement_t *parse_declaration_statement(void)
+{
+       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)
+{
+       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)
 {
-       statement_t *statement = NULL;
+       statement_t   *statement = NULL;
 
        /* declaration or statement */
        switch(token.type) {
@@ -1001,10 +2963,6 @@ statement_t *parse_statement(void)
                statement = parse_default_statement();
                break;
 
-       case T_IDENTIFIER:
-               statement = parse_label_statement();
-               break;
-
        case '{':
                statement = parse_compound_statement();
                break;
@@ -1046,63 +3004,143 @@ statement_t *parse_statement(void)
                break;
 
        case ';':
+               next_token();
                statement = NULL;
                break;
+
+       case T_IDENTIFIER:
+               if(look_ahead(1)->type == ':') {
+                       statement = parse_label_statement();
+                       break;
+               }
+
+               if(is_typedef_symbol(token.v.symbol)) {
+                       statement = parse_declaration_statement();
+                       break;
+               }
+
+               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;
+
+       default:
+               statement = parse_expression_statement();
+               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)
 {
-       expect('{');
+       eat('{');
 
-       while(token.type != '}') {
-               parse_statement();
+       compound_statement_t *compound_statement
+               = allocate_ast_zero(sizeof(compound_statement[0]));
+       compound_statement->statement.type            = STATEMENT_COMPOUND;
+       compound_statement->statement.source_position = token.source_position;
+
+       int        top          = environment_top();
+       context_t *last_context = context;
+       set_context(&compound_statement->context);
+
+       statement_t *last_statement = NULL;
+
+       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;
        }
+
+       assert(context == &compound_statement->context);
+       set_context(last_context);
+       environment_pop_to(top);
+
        next_token();
 
-       return NULL;
+       return (statement_t*) compound_statement;
 }
 
-static
-void parse_translation_unit(void)
+static translation_unit_t *parse_translation_unit(void)
 {
-       declaration_specifiers_t specifiers;
-       memset(&specifiers, 0, sizeof(specifiers));
-       parse_declaration_specifiers(&specifiers);
+       translation_unit_t *unit = allocate_ast_zero(sizeof(unit[0]));
 
-       while(token.type != T_EOF) {
-               if(token.type == '{') {
-                       next_token();
-                       continue;
-               }
+       assert(global_context == NULL);
+       global_context = &unit->context;
 
-               parse_declaration();
-               /* multiple declarations? */
+       assert(context == NULL);
+       set_context(&unit->context);
 
-               if(token.type == '{') {
-                       parse_compound_statement();
-               } else if(token.type == ';') {
-                       next_token();
-               } else {
-                       parse_error_expected("while parsing declarations", '{', ';', 0);
-               }
+       while(token.type != T_EOF) {
+               parse_declaration();
        }
+
+       assert(context == &unit->context);
+       context          = NULL;
+       last_declaration = NULL;
+
+       assert(global_context == &unit->context);
+       global_context = NULL;
+
+       return unit;
 }
 
-void parse(void)
+translation_unit_t *parse(void)
 {
-       next_token();
-       parse_translation_unit();
+       environment_stack = NEW_ARR_F(stack_entry_t, 0);
+
+       type_set_output(stderr);
+
+       lookahead_bufpos = 0;
+       for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
+               next_token();
+       }
+       translation_unit_t *unit = parse_translation_unit();
+
+       DEL_ARR_F(environment_stack);
+
+       return unit;
 }
 
 void init_parser(void)
 {
        init_expression_parsers();
+       obstack_init(&temp_obst);
+
+       type_int        = make_atomic_type(ATOMIC_TYPE_INT, 0);
+       type_double     = make_atomic_type(ATOMIC_TYPE_DOUBLE, 0);
+       type_size_t     = make_atomic_type(ATOMIC_TYPE_UINT, 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)
 {
+       obstack_free(&temp_obst, NULL);
 }