check_reachable() continued at the wrong position, when encountering a break statement.
[cparser] / parser.c
index 8688a93..d403755 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -48,16 +48,24 @@ typedef struct {
        unsigned short namespc;
 } stack_entry_t;
 
+typedef struct argument_list_t argument_list_t;
+struct argument_list_t {
+       long              argument;
+       argument_list_t  *next;
+};
+
 typedef struct gnu_attribute_t gnu_attribute_t;
 struct gnu_attribute_t {
-       gnu_attribute_kind_t kind;
+       gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
        gnu_attribute_t     *next;
-       bool                 invalid;
-       bool                 have_arguments;
+       bool                 invalid;        /**< Set if this attribute had argument errors, */
+       bool                 have_arguments; /**< True, if this attribute has arguments. */
        union {
                size_t              value;
                string_t            string;
                atomic_type_kind_t  akind;
+               long                argument;  /**< Single argument. */
+               argument_list_t    *arguments; /**< List of argument expressions. */
        } u;
 };
 
@@ -100,6 +108,7 @@ static declaration_t      *last_declaration  = NULL;
 static declaration_t      *current_function  = NULL;
 static switch_statement_t *current_switch    = NULL;
 static statement_t        *current_loop      = NULL;
+static statement_t        *current_parent    = NULL;
 static ms_try_statement_t *current_try       = NULL;
 static goto_statement_t   *goto_first        = NULL;
 static goto_statement_t   *goto_last         = NULL;
@@ -108,6 +117,11 @@ static label_statement_t  *label_last        = NULL;
 static translation_unit_t *unit              = NULL;
 static struct obstack      temp_obst;
 
+#define PUSH_PARENT(stmt)                          \
+       statement_t *const prev_parent = current_parent; \
+       current_parent = (stmt);
+#define POP_PARENT ((void)(current_parent = prev_parent))
+
 static source_position_t null_position = { NULL, 0 };
 
 /* symbols for Microsoft extended-decl-modifier */
@@ -157,7 +171,8 @@ static void semantic_comparison(binary_expression_t *expression);
        case T_extern:          \
        case T_static:          \
        case T_auto:            \
-       case T_register:
+       case T_register:        \
+       case T___thread:
 
 #define TYPE_QUALIFIERS     \
        case T_const:           \
@@ -312,7 +327,8 @@ static statement_t *allocate_statement_zero(statement_kind_t kind)
        size_t       size = get_statement_struct_size(kind);
        statement_t *res  = allocate_ast_zero(size);
 
-       res->base.kind = kind;
+       res->base.kind   = kind;
+       res->base.parent = current_parent;
        return res;
 }
 
@@ -391,6 +407,9 @@ static size_t get_type_struct_size(type_kind_t kind)
 /**
  * Allocate a type node of given kind and initialize all
  * fields with zero.
+ *
+ * @param kind             type kind to allocate
+ * @param source_position  the source position of the type definition
  */
 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
 {
@@ -488,19 +507,22 @@ static inline const token_t *look_ahead(int num)
 /**
  * Adds a token to the token anchor set (a multi-set).
  */
-static void add_anchor_token(int token_type) {
+static void add_anchor_token(int token_type)
+{
        assert(0 <= token_type && token_type < T_LAST_TOKEN);
        ++token_anchor_set[token_type];
 }
 
-static int save_and_reset_anchor_state(int token_type) {
+static int save_and_reset_anchor_state(int token_type)
+{
        assert(0 <= token_type && token_type < T_LAST_TOKEN);
        int count = token_anchor_set[token_type];
        token_anchor_set[token_type] = 0;
        return count;
 }
 
-static void restore_anchor_state(int token_type, int count) {
+static void restore_anchor_state(int token_type, int count)
+{
        assert(0 <= token_type && token_type < T_LAST_TOKEN);
        token_anchor_set[token_type] = count;
 }
@@ -508,12 +530,14 @@ static void restore_anchor_state(int token_type, int count) {
 /**
  * Remove a token from the token anchor set (a multi-set).
  */
-static void rem_anchor_token(int token_type) {
+static void rem_anchor_token(int token_type)
+{
        assert(0 <= token_type && token_type < T_LAST_TOKEN);
        --token_anchor_set[token_type];
 }
 
-static bool at_anchor(void) {
+static bool at_anchor(void)
+{
        if (token.type < 0)
                return false;
        return token_anchor_set[token.type];
@@ -522,11 +546,8 @@ static bool at_anchor(void) {
 /**
  * Eat tokens until a matching token is found.
  */
-static void eat_until_matching_token(int type) {
-       unsigned parenthesis_count = 0;
-       unsigned brace_count = 0;
-       unsigned bracket_count = 0;
-
+static void eat_until_matching_token(int type)
+{
        int end_token;
        switch (type) {
                case '(': end_token = ')';  break;
@@ -535,26 +556,40 @@ static void eat_until_matching_token(int type) {
                default:  end_token = type; break;
        }
 
-       while(token.type != end_token ||
-             (parenthesis_count > 0 || brace_count > 0 || bracket_count > 0)) {
-
-               switch(token.type) {
+       unsigned parenthesis_count = 0;
+       unsigned brace_count       = 0;
+       unsigned bracket_count     = 0;
+       while (token.type        != end_token ||
+              parenthesis_count != 0         ||
+              brace_count       != 0         ||
+              bracket_count     != 0) {
+               switch (token.type) {
                case T_EOF: return;
                case '(': ++parenthesis_count; break;
                case '{': ++brace_count;       break;
                case '[': ++bracket_count;     break;
+
                case ')':
                        if (parenthesis_count > 0)
                                --parenthesis_count;
-                       break;
+                       goto check_stop;
+
                case '}':
                        if (brace_count > 0)
                                --brace_count;
-                       break;
+                       goto check_stop;
+
                case ']':
                        if (bracket_count > 0)
                                --bracket_count;
+check_stop:
+                       if (token.type        == end_token &&
+                           parenthesis_count == 0         &&
+                           brace_count       == 0         &&
+                           bracket_count     == 0)
+                               return;
                        break;
+
                default:
                        break;
                }
@@ -565,10 +600,11 @@ static void eat_until_matching_token(int type) {
 /**
  * Eat input tokens until an anchor is found.
  */
-static void eat_until_anchor(void) {
+static void eat_until_anchor(void)
+{
        if (token.type == T_EOF)
                return;
-       while(token_anchor_set[token.type] == 0) {
+       while (token_anchor_set[token.type] == 0) {
                if (token.type == '(' || token.type == '{' || token.type == '[')
                        eat_until_matching_token(token.type);
                if (token.type == T_EOF)
@@ -577,7 +613,8 @@ static void eat_until_anchor(void) {
        }
 }
 
-static void eat_block(void) {
+static void eat_block(void)
+{
        eat_until_matching_token('{');
        if (token.type == '}')
                next_token();
@@ -586,13 +623,14 @@ static void eat_block(void) {
 /**
  * eat all token until a ';' is reached or a stop token is found.
  */
-static void eat_statement(void) {
+static void eat_statement(void)
+{
        eat_until_matching_token(';');
        if (token.type == ';')
                next_token();
 }
 
-#define eat(token_type)  do { assert(token.type == token_type); next_token(); } while(0)
+#define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 
 /**
  * Report a parse error because an expected token was not found.
@@ -648,7 +686,7 @@ static void type_error_incompatible(const char *msg,
         goto end_error;                               \
     }                                                 \
     next_token();                                     \
-       } while(0)
+       } while (0)
 
 static void set_scope(scope_t *new_scope)
 {
@@ -724,6 +762,11 @@ static void environment_push(declaration_t *declaration)
        stack_push(&environment_stack, declaration);
 }
 
+/**
+ * Push a declaration of the label stack.
+ *
+ * @param declaration  the declaration
+ */
 static void label_push(declaration_t *declaration)
 {
        declaration->parent_scope = &current_function->scope;
@@ -785,6 +828,12 @@ static void environment_pop_to(size_t new_top)
        stack_pop_to(&environment_stack, new_top);
 }
 
+/**
+ * Pop all entries on the label stack until the new_top
+ * is reached.
+ *
+ * @param new_top  the new stack top
+ */
 static void label_pop_to(size_t new_top)
 {
        stack_pop_to(&label_stack, new_top);
@@ -1054,7 +1103,7 @@ static string_t parse_string_literals(void)
        return result;
 }
 
-static const char *gnu_attribute_names[GNU_AK_LAST] = {
+static const char *const gnu_attribute_names[GNU_AK_LAST] = {
        [GNU_AK_CONST]                  = "const",
        [GNU_AK_VOLATILE]               = "volatile",
        [GNU_AK_CDECL]                  = "cdecl",
@@ -1068,7 +1117,7 @@ static const char *gnu_attribute_names[GNU_AK_LAST] = {
        [GNU_AK_ALWAYS_INLINE]          = "always_inline",
        [GNU_AK_MALLOC]                 = "malloc",
        [GNU_AK_WEAK]                   = "weak",
-       [GNU_AK_CONSTRUCTOR]            = "constructor",
+       [GNU_AK_CONSTRUCTOR]            = "constructor",
        [GNU_AK_DESTRUCTOR]             = "destructor",
        [GNU_AK_NOTHROW]                = "nothrow",
        [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
@@ -1082,15 +1131,15 @@ static const char *gnu_attribute_names[GNU_AK_LAST] = {
        [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
        [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
        [GNU_AK_LONGCALL]               = "longcall",
-       [GNU_AK_SHORTCALL]              = "shortcall",
+       [GNU_AK_SHORTCALL]              = "shortcall",
        [GNU_AK_LONG_CALL]              = "long_call",
-       [GNU_AK_SHORT_CALL]             = "short_call",
+       [GNU_AK_SHORT_CALL]             = "short_call",
        [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
-       [GNU_AK_INTERRUPT]                              = "interrupt",
-       [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
-       [GNU_AK_NMI_HANDLER]            = "nmi_handler",
-       [GNU_AK_NESTING]                = "nesting",
-       [GNU_AK_NEAR]                   = "near",
+       [GNU_AK_INTERRUPT]              = "interrupt",
+       [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
+       [GNU_AK_NMI_HANDLER]            = "nmi_handler",
+       [GNU_AK_NESTING]                = "nesting",
+       [GNU_AK_NEAR]                   = "near",
        [GNU_AK_FAR]                    = "far",
        [GNU_AK_SIGNAL]                 = "signal",
        [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
@@ -1125,7 +1174,8 @@ static const char *gnu_attribute_names[GNU_AK_LAST] = {
 /**
  * compare two string, ignoring double underscores on the second.
  */
-static int strcmp_underscore(const char *s1, const char *s2) {
+static int strcmp_underscore(const char *s1, const char *s2)
+{
        if (s2[0] == '_' && s2[1] == '_') {
                size_t len2 = strlen(s2);
                size_t len1 = strlen(s1);
@@ -1140,7 +1190,8 @@ static int strcmp_underscore(const char *s1, const char *s2) {
 /**
  * Allocate a new gnu temporal attribute.
  */
-static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind) {
+static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
+{
        gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
        attribute->kind            = kind;
        attribute->next            = NULL;
@@ -1153,13 +1204,14 @@ static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind) {
 /**
  * parse one constant expression argument.
  */
-static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute) {
+static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
+{
        expression_t *expression;
        add_anchor_token(')');
        expression = parse_constant_expression();
        rem_anchor_token(')');
        expect(')');
-       (void)expression;
+       attribute->u.argument = fold_constant(expression);
        return;
 end_error:
        attribute->invalid = true;
@@ -1168,12 +1220,20 @@ end_error:
 /**
  * parse a list of constant expressions arguments.
  */
-static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute) {
-       expression_t *expression;
+static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
+{
+       argument_list_t **list = &attribute->u.arguments;
+       argument_list_t  *entry;
+       expression_t     *expression;
        add_anchor_token(')');
        add_anchor_token(',');
-       while(true){
+       while (true) {
                expression = parse_constant_expression();
+               entry = obstack_alloc(&temp_obst, sizeof(entry));
+               entry->argument = fold_constant(expression);
+               entry->next     = NULL;
+               *list = entry;
+               list = &entry->next;
                if (token.type != ',')
                        break;
                next_token();
@@ -1181,7 +1241,6 @@ static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute) {
        rem_anchor_token(',');
        rem_anchor_token(')');
        expect(')');
-       (void)expression;
        return;
 end_error:
        attribute->invalid = true;
@@ -1210,8 +1269,9 @@ end_error:
 /**
  * parse one tls model.
  */
-static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute) {
-       static const char *tls_models[] = {
+static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
+{
+       static const char *const tls_models[] = {
                "global-dynamic",
                "local-dynamic",
                "initial-exec",
@@ -1234,8 +1294,9 @@ static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute) {
 /**
  * parse one tls model.
  */
-static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute) {
-       static const char *visibilities[] = {
+static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
+{
+       static const char *const visibilities[] = {
                "default",
                "protected",
                "hidden",
@@ -1258,8 +1319,9 @@ static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute) {
 /**
  * parse one (code) model.
  */
-static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute) {
-       static const char *visibilities[] = {
+static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
+{
+       static const char *const visibilities[] = {
                "small",
                "medium",
                "large"
@@ -1320,8 +1382,9 @@ end_error:
 /**
  * parse one interrupt argument.
  */
-static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute) {
-       static const char *interrupts[] = {
+static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
+{
+       static const char *const interrupts[] = {
                "IRQ",
                "FIQ",
                "SWI",
@@ -1345,8 +1408,9 @@ static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute) {
 /**
  * parse ( identifier, const expression, const expression )
  */
-static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute) {
-       static const char *format_names[] = {
+static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
+{
+       static const char *const format_names[] = {
                "printf",
                "scanf",
                "strftime",
@@ -1489,12 +1553,12 @@ static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
        if (token.type != ')') {
                /* find the end of the list */
                if (last != NULL) {
-                       while(last->next != NULL)
+                       while (last->next != NULL)
                                last = last->next;
                }
 
                /* non-empty attribute list */
-               while(true) {
+               while (true) {
                        const char *name;
                        if (token.type == T_const) {
                                name = "const";
@@ -1544,7 +1608,6 @@ static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
                                switch(kind) {
                                case GNU_AK_CONST:
                                case GNU_AK_VOLATILE:
-                               case GNU_AK_DEPRECATED:
                                case GNU_AK_NAKED:
                                case GNU_AK_MALLOC:
                                case GNU_AK_WEAK:
@@ -1552,7 +1615,6 @@ static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
                                case GNU_AK_NOCOMMON:
                                case GNU_AK_SHARED:
                                case GNU_AK_NOTSHARED:
-                               case GNU_AK_UNUSED:
                                case GNU_AK_NO_INSTRUMENT_FUNCTION:
                                case GNU_AK_WARN_UNUSED_RESULT:
                                case GNU_AK_LONGCALL:
@@ -1581,6 +1643,7 @@ static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
                                case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
                                case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
                                case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
+                               case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
                                case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
                                case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
                                case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
@@ -1593,6 +1656,7 @@ static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
                                case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
                                case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
                                case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
+                               case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
 
                                case GNU_AK_ALIGNED:
                                        /* __align__ may be used without an argument */
@@ -1715,7 +1779,7 @@ static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
 {
        decl_modifiers_t modifiers = 0;
 
-       while(true) {
+       while (true) {
                switch(token.type) {
                case T___attribute__:
                        modifiers |= parse_gnu_attribute(attributes);
@@ -1757,7 +1821,7 @@ static designator_t *parse_designation(void)
        designator_t *result = NULL;
        designator_t *last   = NULL;
 
-       while(true) {
+       while (true) {
                designator_t *designator;
                switch(token.type) {
                case '[':
@@ -1921,7 +1985,7 @@ static initializer_t *parse_scalar_initializer(type_t *type,
        }
 
        bool additional_warning_displayed = false;
-       while(braces > 0) {
+       while (braces > 0) {
                if (token.type == ',') {
                        next_token();
                }
@@ -1980,7 +2044,7 @@ static __attribute__((unused)) void debug_print_type_path(
                        }
                        fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
                } else if (is_type_array(type)) {
-                       fprintf(stderr, "[%zd]", entry->v.index);
+                       fprintf(stderr, "[%zu]", entry->v.index);
                } else {
                        fprintf(stderr, "-INVALID-");
                }
@@ -2070,7 +2134,7 @@ static void ascend_to(type_path_t *path, size_t top_path_level)
 {
        size_t len = ARR_LEN(path->path);
 
-       while(len > top_path_level) {
+       while (len > top_path_level) {
                ascend_from_subtype(path);
                len = ARR_LEN(path->path);
        }
@@ -2213,8 +2277,9 @@ static void advance_current_object(type_path_t *path, size_t top_path_level)
 /**
  * skip until token is found.
  */
-static void skip_until(int type) {
-       while(token.type != type) {
+static void skip_until(int type)
+{
+       while (token.type != type) {
                if (token.type == T_EOF)
                        return;
                next_token();
@@ -2229,7 +2294,7 @@ static void skip_initializers(void)
        if (token.type == '{')
                next_token();
 
-       while(token.type != '}') {
+       while (token.type != '}') {
                if (token.type == T_EOF)
                        return;
                if (token.type == '{') {
@@ -2277,11 +2342,20 @@ static initializer_t *parse_sub_initializer(type_path_t *path,
 
        initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
 
-       while(true) {
+       while (true) {
                designator_t *designator = NULL;
                if (token.type == '.' || token.type == '[') {
                        designator = parse_designation();
+                       goto finish_designator;
+               } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
+                       /* GNU-style designator ("identifier: value") */
+                       designator = allocate_ast_zero(sizeof(designator[0]));
+                       designator->source_position = token.source_position;
+                       designator->symbol          = token.v.symbol;
+                       eat(T_IDENTIFIER);
+                       eat(':');
 
+finish_designator:
                        /* reset path to toplevel, evaluate designator from there */
                        ascend_to(path, top_path_level);
                        if (!walk_designator(path, designator, false)) {
@@ -2362,7 +2436,7 @@ static initializer_t *parse_sub_initializer(type_path_t *path,
                        }
 
                        /* descend into subtypes until expression matches type */
-                       while(true) {
+                       while (true) {
                                orig_type = path->top_type;
                                type      = skip_typeref(orig_type);
 
@@ -2643,7 +2717,7 @@ static void parse_enum_entries(type_t *const enum_type)
                if (token.type != ',')
                        break;
                next_token();
-       } while(token.type != '}');
+       } while (token.type != '}');
        rem_anchor_token('}');
 
        expect('}');
@@ -2727,11 +2801,11 @@ static type_t *parse_typeof(void)
 restart:
        switch(token.type) {
        case T___extension__:
-               /* this can be a prefix to a typename or an expression */
-               /* we simply eat it now. */
+               /* This can be a prefix to a typename or an expression.  We simply eat
+                * it now. */
                do {
                        next_token();
-               } while(token.type == T___extension__);
+               } while (token.type == T___extension__);
                goto restart;
 
        case T_IDENTIFIER:
@@ -2765,7 +2839,7 @@ end_error:
        return NULL;
 }
 
-typedef enum {
+typedef enum specifiers_t {
        SPECIFIER_SIGNED    = 1 << 0,
        SPECIFIER_UNSIGNED  = 1 << 1,
        SPECIFIER_LONG      = 1 << 2,
@@ -2817,7 +2891,8 @@ static type_t *get_typedef_type(symbol_t *symbol)
 /**
  * check for the allowed MS alignment values.
  */
-static bool check_elignment_value(long long intvalue) {
+static bool check_alignment_value(long long intvalue)
+{
        if (intvalue < 1 || intvalue > 8192) {
                errorf(HERE, "illegal alignment value");
                return false;
@@ -2834,13 +2909,13 @@ static bool check_elignment_value(long long intvalue) {
 #define DET_MOD(name, tag) do { \
        if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
        *modifiers |= tag; \
-} while(0)
+} while (0)
 
 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
 {
        decl_modifiers_t *modifiers = &specifiers->modifiers;
 
-       while(true) {
+       while (true) {
                if (token.type == T_restrict) {
                        next_token();
                        DET_MOD(restrict, DM_RESTRICT);
@@ -2853,7 +2928,7 @@ static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *spe
                        expect('(');
                        if (token.type != T_INTEGER)
                                goto end_error;
-                       if (check_elignment_value(token.v.intvalue)) {
+                       if (check_alignment_value(token.v.intvalue)) {
                                if (specifiers->alignment != 0)
                                        warningf(HERE, "align used more than once");
                                specifiers->alignment = (unsigned char)token.v.intvalue;
@@ -2982,7 +3057,7 @@ static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
 
        specifiers->source_position = token.source_position;
 
-       while(true) {
+       while (true) {
                specifiers->modifiers
                        |= parse_attributes(&specifiers->gnu_attributes);
                if (specifiers->modifiers & DM_TRANSPARENT_UNION)
@@ -3041,7 +3116,7 @@ static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                case token:                                                     \
                        qualifiers |= qualifier;                                    \
                        next_token();                                               \
-                       break;
+                       break
 
                MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
                MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
@@ -3066,28 +3141,29 @@ static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
                        } 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")
-               MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8")
-               MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16")
-               MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32")
-               MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64")
-               MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128")
-               MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex")
-               MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary")
+                       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");
+               MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
+               MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
+               MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
+               MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
+               MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
+               MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
+               MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
 
                case T__forceinline:
                        /* only in microsoft mode */
                        specifiers->modifiers |= DM_FORCEINLINE;
+                       /* FALLTHROUGH */
 
                case T_inline:
                        next_token();
@@ -3198,17 +3274,24 @@ finish_specifiers:
                case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
                        atomic_type = ATOMIC_TYPE_ULONG;
                        break;
+
                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;
+                       goto warn_about_long_long;
+
                case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
                case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
                        | SPECIFIER_INT:
                        atomic_type = ATOMIC_TYPE_ULONGLONG;
+warn_about_long_long:
+                       if (warning.long_long) {
+                               warningf(&specifiers->source_position,
+                                        "ISO C90 does not support 'long long'");
+                       }
                        break;
 
                case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
@@ -3341,7 +3424,7 @@ static type_qualifiers_t parse_type_qualifiers(void)
 {
        type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
 
-       while(true) {
+       while (true) {
                switch(token.type) {
                /* type qualifiers */
                MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
@@ -3382,11 +3465,13 @@ static declaration_t *parse_identifier_list(void)
                        break;
                }
                next_token();
-       } while(token.type == T_IDENTIFIER);
+       } while (token.type == T_IDENTIFIER);
 
        return declarations;
 }
 
+static type_t *automatic_type_conversion(type_t *orig_type);
+
 static void semantic_parameter(declaration_t *declaration)
 {
        /* TODO: improve error messages */
@@ -3399,19 +3484,15 @@ static void semantic_parameter(declaration_t *declaration)
        }
 
        type_t *const orig_type = declaration->type;
-       type_t *      type      = skip_typeref(orig_type);
-
-       /* Array as last part of a parameter type is just syntactic sugar.  Turn it
-        * into a pointer. Â§ 6.7.5.3 (7) */
-       if (is_type_array(type)) {
-               type_t *const element_type = type->array.element_type;
-
-               type = make_pointer_type(element_type, type->base.qualifiers);
-
-               declaration->type = type;
-       }
+       /* Â§6.7.5.3(7): Array as last part of a parameter type is just syntactic
+        * sugar.  Turn it into a pointer.
+        * Â§6.7.5.3(8): A declaration of a parameter as ``function returning type''
+        * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
+        */
+       type_t *const type = automatic_type_conversion(orig_type);
+       declaration->type = type;
 
-       if (is_type_incomplete(type)) {
+       if (is_type_incomplete(skip_typeref(type))) {
                errorf(HERE, "incomplete type '%T' not allowed for parameter '%Y'",
                       orig_type, declaration->symbol);
        }
@@ -3456,7 +3537,7 @@ static declaration_t *parse_parameters(function_type_t *type)
        function_parameter_t *parameter;
        function_parameter_t *last_parameter = NULL;
 
-       while(true) {
+       while (true) {
                switch(token.type) {
                case T_DOTDOTDOT:
                        next_token();
@@ -3514,7 +3595,7 @@ end_error:
        return NULL;
 }
 
-typedef enum {
+typedef enum construct_type_kind_t {
        CONSTRUCT_INVALID,
        CONSTRUCT_POINTER,
        CONSTRUCT_FUNCTION,
@@ -3609,6 +3690,40 @@ static construct_type_t *parse_function_declarator(declaration_t *declaration)
        type_t *type;
        if (declaration != NULL) {
                type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
+
+               unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
+
+               if (mask & (mask-1)) {
+                       const char *first = NULL, *second = NULL;
+
+                       /* more than one calling convention set */
+                       if (declaration->modifiers & DM_CDECL) {
+                               if (first == NULL)       first = "cdecl";
+                               else if (second == NULL) second = "cdecl";
+                       }
+                       if (declaration->modifiers & DM_STDCALL) {
+                               if (first == NULL)       first = "stdcall";
+                               else if (second == NULL) second = "stdcall";
+                       }
+                       if (declaration->modifiers & DM_FASTCALL) {
+                               if (first == NULL)       first = "faslcall";
+                               else if (second == NULL) second = "fastcall";
+                       }
+                       if (declaration->modifiers & DM_THISCALL) {
+                               if (first == NULL)       first = "thiscall";
+                               else if (second == NULL) second = "thiscall";
+                       }
+                       errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
+               }
+
+               if (declaration->modifiers & DM_CDECL)
+                       type->function.calling_convention = CC_CDECL;
+               else if (declaration->modifiers & DM_STDCALL)
+                       type->function.calling_convention = CC_STDCALL;
+               else if (declaration->modifiers & DM_FASTCALL)
+                       type->function.calling_convention = CC_FASTCALL;
+               else if (declaration->modifiers & DM_THISCALL)
+                       type->function.calling_convention = CC_THISCALL;
        } else {
                type = allocate_type_zero(TYPE_FUNCTION, HERE);
        }
@@ -3624,7 +3739,7 @@ static construct_type_t *parse_function_declarator(declaration_t *declaration)
        construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
        construct_function_type->function_type       = type;
 
-       return (construct_type_t*) construct_function_type;
+       return &construct_function_type->construct_type;
 }
 
 static void fix_declaration_type(declaration_t *declaration)
@@ -3661,7 +3776,7 @@ static construct_type_t *parse_inner_declarator(declaration_t *declaration,
        decl_modifiers_t modifiers = parse_attributes(&attributes);
 
        /* pointers */
-       while(token.type == '*') {
+       while (token.type == '*') {
                construct_type_t *type = parse_pointer_declarator();
 
                if (last == NULL) {
@@ -3676,6 +3791,9 @@ static construct_type_t *parse_inner_declarator(declaration_t *declaration,
                modifiers |= parse_attributes(&attributes);
        }
 
+       if (declaration != NULL)
+               declaration->modifiers |= modifiers;
+
        construct_type_t *inner_types = NULL;
 
        switch(token.type) {
@@ -3883,7 +4001,6 @@ static declaration_t *parse_declarator(
        declaration_t *const declaration    = allocate_declaration_zero();
        declaration->declared_storage_class = specifiers->declared_storage_class;
        declaration->modifiers              = specifiers->modifiers;
-       declaration->deprecated             = specifiers->deprecated;
        declaration->deprecated_string      = specifiers->deprecated_string;
        declaration->get_property_sym       = specifiers->get_property_sym;
        declaration->put_property_sym       = specifiers->put_property_sym;
@@ -3982,11 +4099,11 @@ static void check_type_of_main(const declaration_t *const decl, const function_t
                                                 "third argument of 'main' should be 'char**', but is '%T'", third_type);
                                }
                                parm = parm->next;
-                               if (parm != NULL) {
-                                       warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
-                               }
+                               if (parm != NULL)
+                                       goto warn_arg_count;
                        }
                } else {
+warn_arg_count:
                        warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
                }
        }
@@ -4002,12 +4119,12 @@ static bool is_sym_main(const symbol_t *const sym)
 
 static declaration_t *internal_record_declaration(
        declaration_t *const declaration,
-       const bool is_function_definition)
+       const bool is_definition)
 {
        const symbol_t *const symbol  = declaration->symbol;
        const namespace_t     namespc = (namespace_t)declaration->namespc;
 
-       assert(declaration->symbol != NULL);
+       assert(symbol != NULL);
        declaration_t *previous_declaration = get_declaration(symbol, namespc);
 
        type_t *const orig_type = declaration->type;
@@ -4021,10 +4138,17 @@ static declaration_t *internal_record_declaration(
                         orig_type, declaration->symbol);
        }
 
-       if (is_function_definition && warning.main && is_sym_main(symbol)) {
+       if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
                check_type_of_main(declaration, &type->function);
        }
 
+       if (warning.nested_externs                             &&
+           declaration->storage_class == STORAGE_CLASS_EXTERN &&
+           scope                      != global_scope) {
+               warningf(&declaration->source_position,
+                        "nested extern declaration of '%#T'", declaration->type, symbol);
+       }
+
        assert(declaration != previous_declaration);
        if (previous_declaration != NULL
                        && previous_declaration->parent_scope == scope) {
@@ -4048,6 +4172,16 @@ static declaration_t *internal_record_declaration(
                                return previous_declaration;
                        }
 
+                       if (warning.redundant_decls                                     &&
+                           is_definition                                               &&
+                           previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
+                           !(previous_declaration->modifiers & DM_USED)                &&
+                           !previous_declaration->used) {
+                               warningf(&previous_declaration->source_position,
+                                        "unnecessary static forward declaration for '%#T'",
+                                        previous_declaration->type, symbol);
+                       }
+
                        unsigned new_storage_class = declaration->storage_class;
 
                        if (is_type_incomplete(prev_type)) {
@@ -4070,10 +4204,10 @@ static declaration_t *internal_record_declaration(
                                        /* FALLTHROUGH */
 
                                case STORAGE_CLASS_EXTERN:
-                                       if (is_function_definition) {
+                                       if (is_definition) {
                                                if (warning.missing_prototypes &&
-                                                       prev_type->function.unspecified_parameters &&
-                                                       !is_sym_main(symbol)) {
+                                                   prev_type->function.unspecified_parameters &&
+                                                   !is_sym_main(symbol)) {
                                                        warningf(&declaration->source_position,
                                                                         "no previous prototype for '%#T'",
                                                                         orig_type, symbol);
@@ -4091,40 +4225,42 @@ static declaration_t *internal_record_declaration(
                        if (old_storage_class == STORAGE_CLASS_EXTERN &&
                                        new_storage_class == STORAGE_CLASS_EXTERN) {
 warn_redundant_declaration:
-                               if (warning.redundant_decls && strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
+                               if (!is_definition          &&
+                                   warning.redundant_decls &&
+                                   strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
                                        warningf(&declaration->source_position,
-                                                        "redundant declaration for '%Y' (declared %P)",
-                                                        symbol, &previous_declaration->source_position);
+                                                "redundant declaration for '%Y' (declared %P)",
+                                                symbol, &previous_declaration->source_position);
                                }
                        } else if (current_function == NULL) {
                                if (old_storage_class != STORAGE_CLASS_STATIC &&
-                                               new_storage_class == STORAGE_CLASS_STATIC) {
+                                   new_storage_class == STORAGE_CLASS_STATIC) {
                                        errorf(&declaration->source_position,
-                                                  "static declaration of '%Y' follows non-static declaration (declared %P)",
-                                                  symbol, &previous_declaration->source_position);
-                               } else if (old_storage_class != STORAGE_CLASS_EXTERN
-                                               && !is_function_definition) {
-                                       goto warn_redundant_declaration;
+                                              "static declaration of '%Y' follows non-static declaration (declared %P)",
+                                              symbol, &previous_declaration->source_position);
                                } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
                                        previous_declaration->storage_class          = STORAGE_CLASS_NONE;
                                        previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
+                               } else {
+                                       goto warn_redundant_declaration;
                                }
                        } else if (old_storage_class == new_storage_class) {
                                errorf(&declaration->source_position,
-                                          "redeclaration of '%Y' (declared %P)",
-                                          symbol, &previous_declaration->source_position);
+                                      "redeclaration of '%Y' (declared %P)",
+                                      symbol, &previous_declaration->source_position);
                        } else {
                                errorf(&declaration->source_position,
-                                          "redeclaration of '%Y' with different linkage (declared %P)",
-                                          symbol, &previous_declaration->source_position);
+                                      "redeclaration of '%Y' with different linkage (declared %P)",
+                                      symbol, &previous_declaration->source_position);
                        }
                }
 
-               if (declaration->is_inline)
-                       previous_declaration->is_inline = true;
+               previous_declaration->modifiers |= declaration->modifiers;
+               previous_declaration->is_inline |= declaration->is_inline;
                return previous_declaration;
-       } else if (is_function_definition) {
-               if (declaration->storage_class != STORAGE_CLASS_STATIC) {
+       } else if (is_type_function(type)) {
+               if (is_definition &&
+                   declaration->storage_class != STORAGE_CLASS_STATIC) {
                        if (warning.missing_prototypes && !is_sym_main(symbol)) {
                                warningf(&declaration->source_position,
                                         "no previous prototype for '%#T'", orig_type, symbol);
@@ -4134,14 +4270,15 @@ warn_redundant_declaration:
                                         symbol);
                        }
                }
-       } else if (warning.missing_declarations &&
-           scope == global_scope &&
-           !is_type_function(type) && (
-             declaration->storage_class == STORAGE_CLASS_NONE ||
-             declaration->storage_class == STORAGE_CLASS_THREAD
-           )) {
-               warningf(&declaration->source_position,
-                        "no previous declaration for '%#T'", orig_type, symbol);
+       } else {
+               if (warning.missing_declarations &&
+                   scope == global_scope && (
+                     declaration->storage_class == STORAGE_CLASS_NONE ||
+                     declaration->storage_class == STORAGE_CLASS_THREAD
+                   )) {
+                       warningf(&declaration->source_position,
+                                "no previous declaration for '%#T'", orig_type, symbol);
+               }
        }
 
        assert(declaration->parent_scope == NULL);
@@ -4158,7 +4295,7 @@ static declaration_t *record_declaration(declaration_t *declaration)
        return internal_record_declaration(declaration, false);
 }
 
-static declaration_t *record_function_definition(declaration_t *declaration)
+static declaration_t *record_definition(declaration_t *declaration)
 {
        return internal_record_declaration(declaration, true);
 }
@@ -4462,7 +4599,8 @@ static bool first_err = true;
  * When called with first_err set, prints the name of the current function,
  * else does noting.
  */
-static void print_in_function(void) {
+static void print_in_function(void)
+{
        if (first_err) {
                first_err = false;
                diagnosticf("%s: In function '%Y':\n",
@@ -4528,6 +4666,429 @@ static void check_declarations(void)
        }
 }
 
+static int determine_truth(expression_t const* const cond)
+{
+       return
+               !is_constant_expression(cond) ? 0 :
+               fold_constant(cond) != 0      ? 1 :
+               -1;
+}
+
+static bool noreturn_candidate;
+
+static void check_reachable(statement_t *const stmt)
+{
+       if (stmt->base.reachable)
+               return;
+       if (stmt->kind != STATEMENT_DO_WHILE)
+               stmt->base.reachable = true;
+
+       statement_t *last = stmt;
+       statement_t *next;
+       switch (stmt->kind) {
+               case STATEMENT_INVALID:
+               case STATEMENT_EMPTY:
+               case STATEMENT_DECLARATION:
+               case STATEMENT_ASM:
+                       next = stmt->base.next;
+                       break;
+
+               case STATEMENT_COMPOUND:
+                       next = stmt->compound.statements;
+                       break;
+
+               case STATEMENT_RETURN:
+                       noreturn_candidate = false;
+                       return;
+
+               case STATEMENT_IF: {
+                       if_statement_t const* const ifs = &stmt->ifs;
+                       int            const        val = determine_truth(ifs->condition);
+
+                       if (val >= 0)
+                               check_reachable(ifs->true_statement);
+
+                       if (val > 0)
+                               return;
+
+                       if (ifs->false_statement != NULL) {
+                               check_reachable(ifs->false_statement);
+                               return;
+                       }
+
+                       next = stmt->base.next;
+                       break;
+               }
+
+               case STATEMENT_SWITCH: {
+                       switch_statement_t const *const switchs = &stmt->switchs;
+                       expression_t       const *const expr    = switchs->expression;
+
+                       if (is_constant_expression(expr)) {
+                               long                    const val      = fold_constant(expr);
+                               case_label_statement_t *      defaults = NULL;
+                               for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
+                                       if (i->expression == NULL) {
+                                               defaults = i;
+                                               continue;
+                                       }
+
+                                       expression_t *const case_expr = i->expression;
+                                       if (is_constant_expression(case_expr) &&
+                                           fold_constant(case_expr) == val) {
+                                               check_reachable((statement_t*)i);
+                                               return;
+                                       }
+                               }
+
+                               if (defaults != NULL) {
+                                       check_reachable((statement_t*)defaults);
+                                       return;
+                               }
+                       } else {
+                               bool has_default = false;
+                               for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
+                                       if (i->expression == NULL)
+                                               has_default = true;
+
+                                       check_reachable((statement_t*)i);
+                               }
+
+                               if (has_default)
+                                       return;
+                       }
+
+                       next = stmt->base.next;
+                       break;
+               }
+
+               case STATEMENT_EXPRESSION: {
+                       /* Check for noreturn function call */
+                       expression_t const *const expr = stmt->expression.expression;
+                       if (expr->kind == EXPR_CALL) {
+                               expression_t const *const func = expr->call.function;
+                               if (func->kind == EXPR_REFERENCE) {
+                                       declaration_t const *const decl = func->reference.declaration;
+                                       if (decl != NULL && decl->modifiers & DM_NORETURN) {
+                                               return;
+                                       }
+                               }
+                       }
+
+                       next = stmt->base.next;
+                       break;
+               }
+
+               case STATEMENT_CONTINUE: {
+                       statement_t *parent = stmt;
+                       for (;;) {
+                               parent = parent->base.parent;
+                               if (parent == NULL) /* continue not within loop */
+                                       return;
+
+                               next = parent;
+                               switch (parent->kind) {
+                                       case STATEMENT_WHILE:    goto continue_while;
+                                       case STATEMENT_DO_WHILE: goto continue_do_while;
+                                       case STATEMENT_FOR:      goto continue_for;
+
+                                       default: break;
+                               }
+                       }
+               }
+
+               case STATEMENT_BREAK: {
+                       statement_t *parent = stmt;
+                       for (;;) {
+                               parent = parent->base.parent;
+                               if (parent == NULL) /* break not within loop/switch */
+                                       return;
+
+                               switch (parent->kind) {
+                                       case STATEMENT_SWITCH:
+                                       case STATEMENT_WHILE:
+                                       case STATEMENT_DO_WHILE:
+                                       case STATEMENT_FOR:
+                                               last = parent;
+                                               next = parent->base.next;
+                                               goto found_break_parent;
+
+                                       default: break;
+                               }
+                       }
+found_break_parent:
+                       break;
+               }
+
+               case STATEMENT_GOTO:
+                       next = stmt->gotos.label->init.statement;
+                       if (next == NULL) /* missing label */
+                               return;
+                       break;
+
+               case STATEMENT_LABEL:
+                       next = stmt->label.statement;
+                       break;
+
+               case STATEMENT_CASE_LABEL:
+                       next = stmt->case_label.statement;
+                       break;
+
+               case STATEMENT_WHILE: {
+                       while_statement_t const *const whiles = &stmt->whiles;
+                       int                      const val    = determine_truth(whiles->condition);
+
+                       if (val >= 0)
+                               check_reachable(whiles->body);
+
+                       if (val > 0)
+                               return;
+
+                       next = stmt->base.next;
+                       break;
+               }
+
+               case STATEMENT_DO_WHILE:
+                       next = stmt->do_while.body;
+                       break;
+
+               case STATEMENT_FOR: {
+                       for_statement_t *const fors = &stmt->fors;
+
+                       if (fors->condition_reachable)
+                               return;
+                       fors->condition_reachable = true;
+
+                       expression_t const *const cond = fors->condition;
+                       int          const        val  =
+                               cond == NULL ? 1 : determine_truth(cond);
+
+                       if (val >= 0)
+                               check_reachable(fors->body);
+
+                       if (val > 0)
+                               return;
+
+                       next = stmt->base.next;
+                       break;
+               }
+
+               case STATEMENT_MS_TRY:
+               case STATEMENT_LEAVE:
+                       panic("unimplemented");
+       }
+
+       while (next == NULL) {
+               next = last->base.parent;
+               if (next == NULL) {
+                       noreturn_candidate = false;
+
+                       type_t *const type = current_function->type;
+                       assert(is_type_function(type));
+                       type_t *const ret  = skip_typeref(type->function.return_type);
+                       if (warning.return_type                    &&
+                           !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
+                           !is_sym_main(current_function->symbol)) {
+                               warningf(&stmt->base.source_position,
+                                        "control reaches end of non-void function");
+                       }
+                       return;
+               }
+
+               switch (next->kind) {
+                       case STATEMENT_INVALID:
+                       case STATEMENT_EMPTY:
+                       case STATEMENT_DECLARATION:
+                       case STATEMENT_EXPRESSION:
+                       case STATEMENT_ASM:
+                       case STATEMENT_RETURN:
+                       case STATEMENT_CONTINUE:
+                       case STATEMENT_BREAK:
+                       case STATEMENT_GOTO:
+                       case STATEMENT_LEAVE:
+                               panic("invalid control flow in function");
+
+                       case STATEMENT_COMPOUND:
+                       case STATEMENT_IF:
+                       case STATEMENT_SWITCH:
+                       case STATEMENT_LABEL:
+                       case STATEMENT_CASE_LABEL:
+                               last = next;
+                               next = next->base.next;
+                               break;
+
+                       case STATEMENT_WHILE: {
+continue_while:
+                               if (next->base.reachable)
+                                       return;
+                               next->base.reachable = true;
+
+                               while_statement_t const *const whiles = &next->whiles;
+                               int                      const val    = determine_truth(whiles->condition);
+
+                               if (val >= 0)
+                                       check_reachable(whiles->body);
+
+                               if (val > 0)
+                                       return;
+
+                               last = next;
+                               next = next->base.next;
+                               break;
+                       }
+
+                       case STATEMENT_DO_WHILE: {
+continue_do_while:
+                               if (next->base.reachable)
+                                       return;
+                               next->base.reachable = true;
+
+                               do_while_statement_t const *const dw  = &next->do_while;
+                               int                  const        val = determine_truth(dw->condition);
+
+                               if (val >= 0)
+                                       check_reachable(dw->body);
+
+                               if (val > 0)
+                                       return;
+
+                               last = next;
+                               next = next->base.next;
+                               break;
+                       }
+
+                       case STATEMENT_FOR: {
+continue_for:;
+                               for_statement_t *const fors = &next->fors;
+
+                               fors->step_reachable = true;
+
+                               if (fors->condition_reachable)
+                                       return;
+                               fors->condition_reachable = true;
+
+                               expression_t const *const cond = fors->condition;
+                               int          const        val  =
+                                       cond == NULL ? 1 : determine_truth(cond);
+
+                               if (val >= 0)
+                                       check_reachable(fors->body);
+
+                               if (val > 0)
+                                       return;
+
+                               last = next;
+                               next = next->base.next;
+                               break;
+                       }
+
+                       case STATEMENT_MS_TRY:
+                               panic("unimplemented");
+               }
+       }
+
+       if (next == NULL) {
+               next = stmt->base.parent;
+               if (next == NULL) {
+                       warningf(&stmt->base.source_position,
+                                "control reaches end of non-void function");
+               }
+       }
+
+       check_reachable(next);
+}
+
+static void check_unreachable(statement_t const* const stmt)
+{
+       if (!stmt->base.reachable            &&
+           stmt->kind != STATEMENT_COMPOUND &&
+           stmt->kind != STATEMENT_DO_WHILE &&
+           stmt->kind != STATEMENT_FOR) {
+               warningf(&stmt->base.source_position,
+                        "statement is unreachable");
+       }
+
+       switch (stmt->kind) {
+               case STATEMENT_INVALID:
+               case STATEMENT_EMPTY:
+               case STATEMENT_RETURN:
+               case STATEMENT_DECLARATION:
+               case STATEMENT_EXPRESSION:
+               case STATEMENT_CONTINUE:
+               case STATEMENT_BREAK:
+               case STATEMENT_GOTO:
+               case STATEMENT_ASM:
+               case STATEMENT_LEAVE:
+                       break;
+
+               case STATEMENT_COMPOUND:
+                       if (stmt->compound.statements)
+                               check_unreachable(stmt->compound.statements);
+                       break;
+
+               case STATEMENT_IF:
+                       check_unreachable(stmt->ifs.true_statement);
+                       if (stmt->ifs.false_statement != NULL)
+                               check_unreachable(stmt->ifs.false_statement);
+                       break;
+
+               case STATEMENT_SWITCH:
+                       check_unreachable(stmt->switchs.body);
+                       break;
+
+               case STATEMENT_LABEL:
+                       check_unreachable(stmt->label.statement);
+                       break;
+
+               case STATEMENT_CASE_LABEL:
+                       check_unreachable(stmt->case_label.statement);
+                       break;
+
+               case STATEMENT_WHILE:
+                       check_unreachable(stmt->whiles.body);
+                       break;
+
+               case STATEMENT_DO_WHILE:
+                       check_unreachable(stmt->do_while.body);
+                       if (!stmt->base.reachable) {
+                               expression_t const *const cond = stmt->do_while.condition;
+                               if (determine_truth(cond) >= 0) {
+                                       warningf(&cond->base.source_position,
+                                                "condition of do-while-loop is unreachable");
+                               }
+                       }
+                       break;
+
+               case STATEMENT_FOR: {
+                       for_statement_t const* const fors = &stmt->fors;
+
+                       if (!stmt->base.reachable && fors->initialisation != NULL) {
+                               warningf(&fors->initialisation->base.source_position,
+                                        "initialisation of for-statement is unreachable");
+                       }
+
+                       if (!fors->condition_reachable && fors->condition != NULL) {
+                               warningf(&fors->condition->base.source_position,
+                                        "condition of for-statement is unreachable");
+                       }
+
+                       if (!fors->step_reachable && fors->step != NULL) {
+                               warningf(&fors->step->base.source_position,
+                                        "step of for-statement is unreachable");
+                       }
+
+                       check_unreachable(stmt->fors.body);
+                       break;
+               }
+
+               case STATEMENT_MS_TRY:
+                       panic("unimplemented");
+       }
+
+       if (stmt->base.next)
+               check_unreachable(stmt->base.next);
+}
+
 static void parse_external_declaration(void)
 {
        /* function-definitions and declarations both start with declaration
@@ -4557,9 +5118,15 @@ static void parse_external_declaration(void)
        rem_anchor_token(';');
 
        /* must be a declaration */
-       if (token.type == ',' || token.type == '=' || token.type == ';') {
-               parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
-               return;
+       switch (token.type) {
+               case ',':
+               case ';':
+                       parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
+                       return;
+
+               case '=':
+                       parse_declaration_rest(ndeclaration, &specifiers, record_definition);
+                       return;
        }
 
        /* must be a function definition */
@@ -4599,7 +5166,7 @@ static void parse_external_declaration(void)
                ndeclaration->type = type;
        }
 
-       declaration_t *const declaration = record_function_definition(ndeclaration);
+       declaration_t *const declaration = record_definition(ndeclaration);
        if (ndeclaration != declaration) {
                declaration->scope = ndeclaration->scope;
        }
@@ -4628,24 +5195,40 @@ static void parse_external_declaration(void)
        if (declaration->init.statement != NULL) {
                parser_error_multiple_definition(declaration, HERE);
                eat_block();
-               goto end_of_parse_external_declaration;
        } else {
                /* parse function body */
                int            label_stack_top      = label_top();
                declaration_t *old_current_function = current_function;
                current_function                    = declaration;
+               current_parent                      = NULL;
 
-               declaration->init.statement = parse_compound_statement(false);
+               statement_t *const body = parse_compound_statement(false);
+               declaration->init.statement = body;
                first_err = true;
                check_labels();
                check_declarations();
+               if (warning.return_type      ||
+                   warning.unreachable_code ||
+                   (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
+                       noreturn_candidate = true;
+                       check_reachable(body);
+                       if (warning.unreachable_code)
+                               check_unreachable(body);
+                       if (warning.missing_noreturn &&
+                           noreturn_candidate       &&
+                           !(declaration->modifiers & DM_NORETURN)) {
+                               warningf(&body->base.source_position,
+                                        "function '%#T' is candidate for attribute 'noreturn'",
+                                        type, declaration->symbol);
+                       }
+               }
 
+               assert(current_parent   == NULL);
                assert(current_function == declaration);
                current_function = old_current_function;
                label_pop_to(label_stack_top);
        }
 
-end_of_parse_external_declaration:
        assert(scope == &declaration->scope);
        set_scope(last_scope);
        environment_pop_to(top);
@@ -5218,18 +5801,20 @@ static expression_t *parse_reference(void)
        declaration->used = true;
 
        /* check for deprecated functions */
-       if (declaration->deprecated != 0) {
-               const char *prefix = "";
-               if (is_type_function(declaration->type))
-                       prefix = "function ";
+       if (warning.deprecated_declarations &&
+           declaration->modifiers & DM_DEPRECATED) {
+               char const *const prefix = is_type_function(declaration->type) ?
+                       "function" : "variable";
 
                if (declaration->deprecated_string != NULL) {
                        warningf(&source_position,
-                               "%s'%Y' was declared 'deprecated(\"%s\")'", prefix, declaration->symbol,
+                               "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
+                               declaration->symbol, &declaration->source_position,
                                declaration->deprecated_string);
                } else {
                        warningf(&source_position,
-                               "%s'%Y' was declared 'deprecated'", prefix, declaration->symbol);
+                               "%s '%Y' is deprecated (declared %P)", prefix,
+                               declaration->symbol, &declaration->source_position);
                }
        }
 
@@ -5718,7 +6303,8 @@ end_error:
 /**
  * Parses a MS assume() expression.
  */
-static expression_t *parse_assume(void) {
+static expression_t *parse_assume(void)
+{
        eat(T__assume);
 
        expression_t *expression
@@ -5739,7 +6325,8 @@ end_error:
 /**
  * Parse a microsoft __noop expression.
  */
-static expression_t *parse_noop_expression(void) {
+static expression_t *parse_noop_expression(void)
+{
        source_position_t source_position = *HERE;
        eat(T___noop);
 
@@ -5824,7 +6411,8 @@ static expression_t *parse_primary_expression(void)
 /**
  * Check if the expression has the character type and issue a warning then.
  */
-static void check_for_char_index_type(const expression_t *expression) {
+static void check_for_char_index_type(const expression_t *expression)
+{
        type_t       *const type      = expression->base.type;
        const type_t *const base_type = skip_typeref(type);
 
@@ -6543,29 +7131,57 @@ static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
                return type_float;
        }
 
-       type_right = promote_integer(type_right);
        type_left  = promote_integer(type_left);
+       type_right = promote_integer(type_right);
 
        if (type_left == type_right)
                return type_left;
 
-       bool signed_left  = is_type_signed(type_left);
-       bool signed_right = is_type_signed(type_right);
-       int  rank_left    = get_rank(type_left);
-       int  rank_right   = get_rank(type_right);
-       if (rank_left < rank_right) {
-               if (signed_left == signed_right || !signed_right) {
-                       return type_right;
-               } else {
-                       return type_left;
-               }
+       bool const signed_left  = is_type_signed(type_left);
+       bool const signed_right = is_type_signed(type_right);
+       int  const rank_left    = get_rank(type_left);
+       int  const rank_right   = get_rank(type_right);
+
+       if (signed_left == signed_right)
+               return rank_left >= rank_right ? type_left : type_right;
+
+       int     s_rank;
+       int     u_rank;
+       type_t *s_type;
+       type_t *u_type;
+       if (signed_left) {
+               s_rank = rank_left;
+               s_type = type_left;
+               u_rank = rank_right;
+               u_type = type_right;
        } else {
-               if (signed_left == signed_right || !signed_left) {
-                       return type_left;
-               } else {
-                       return type_right;
-               }
+               s_rank = rank_right;
+               s_type = type_right;
+               u_rank = rank_left;
+               u_type = type_left;
+       }
+
+       if (u_rank >= s_rank)
+               return u_type;
+
+       if (get_atomic_type_size(s_rank) > get_atomic_type_size(u_rank))
+               return s_type;
+
+       /* FIXME ugly */
+       type_t *const type = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
+       switch (s_rank) {
+               case ATOMIC_TYPE_INT:      type->atomic.akind = ATOMIC_TYPE_UINT;      break;
+               case ATOMIC_TYPE_LONG:     type->atomic.akind = ATOMIC_TYPE_ULONG;     break;
+               case ATOMIC_TYPE_LONGLONG: type->atomic.akind = ATOMIC_TYPE_ULONGLONG; break;
+
+               default: panic("invalid atomic type");
        }
+
+       type_t* const result = typehash_insert(type);
+       if (result != type)
+               free_type(type);
+
+       return result;
 }
 
 /**
@@ -7340,12 +7956,60 @@ static asm_argument_t *parse_asm_arguments(bool is_out)
 
                argument->constraints = parse_string_literals();
                expect('(');
+               add_anchor_token(')');
                expression_t *expression = parse_expression();
-               argument->expression     = expression;
-               if (is_out && !is_lvalue(expression)) {
-                       errorf(&expression->base.source_position,
-                              "asm output argument is not an lvalue");
+               rem_anchor_token(')');
+               if (is_out) {
+                       /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
+                        * change size or type representation (e.g. int -> long is ok, but
+                        * int -> float is not) */
+                       if (expression->kind == EXPR_UNARY_CAST) {
+                               type_t      *const type = expression->base.type;
+                               type_kind_t  const kind = type->kind;
+                               if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
+                                       unsigned flags;
+                                       unsigned size;
+                                       if (kind == TYPE_ATOMIC) {
+                                               atomic_type_kind_t const akind = type->atomic.akind;
+                                               flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
+                                               size  = get_atomic_type_size(akind);
+                                       } else {
+                                               flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
+                                               size  = get_atomic_type_size(get_intptr_kind());
+                                       }
+
+                                       do {
+                                               expression_t *const value      = expression->unary.value;
+                                               type_t       *const value_type = value->base.type;
+                                               type_kind_t   const value_kind = value_type->kind;
+
+                                               unsigned value_flags;
+                                               unsigned value_size;
+                                               if (value_kind == TYPE_ATOMIC) {
+                                                       atomic_type_kind_t const value_akind = value_type->atomic.akind;
+                                                       value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
+                                                       value_size  = get_atomic_type_size(value_akind);
+                                               } else if (value_kind == TYPE_POINTER) {
+                                                       value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
+                                                       value_size  = get_atomic_type_size(get_intptr_kind());
+                                               } else {
+                                                       break;
+                                               }
+
+                                               if (value_flags != flags || value_size != size)
+                                                       break;
+
+                                               expression = value;
+                                       } while (expression->kind == EXPR_UNARY_CAST);
+                               }
+                       }
+
+                       if (!is_lvalue(expression)) {
+                               errorf(&expression->base.source_position,
+                                      "asm output argument is not an lvalue");
+                       }
                }
+               argument->expression = expression;
                expect(')');
 
                set_address_taken(expression, true);
@@ -7443,6 +8107,13 @@ end_of_asm:
        rem_anchor_token(')');
        expect(')');
        expect(';');
+
+       if (asm_statement->outputs == NULL) {
+               /* GCC: An 'asm' instruction without any output operands will be treated
+                * identically to a volatile 'asm' instruction. */
+               asm_statement->is_volatile = true;
+       }
+
        return statement;
 end_error:
        return create_invalid_statement();
@@ -7455,11 +8126,14 @@ static statement_t *parse_case_statement(void)
 {
        eat(T_case);
 
-       statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
+       statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
+       source_position_t *const pos       = &statement->base.source_position;
 
-       statement->base.source_position  = token.source_position;
+       *pos                             = token.source_position;
        statement->case_label.expression = parse_expression();
 
+       PUSH_PARENT(statement);
+
        if (c_mode & _GNUC) {
                if (token.type == T_DOTDOTDOT) {
                        next_token();
@@ -7470,27 +8144,42 @@ static statement_t *parse_case_statement(void)
        expect(':');
 
        if (! is_constant_expression(statement->case_label.expression)) {
-               errorf(&statement->base.source_position,
-                      "case label does not reduce to an integer constant");
-       } else {
-               /* TODO: check if the case label is already known */
-               if (current_switch != NULL) {
-                       /* link all cases into the switch statement */
-                       if (current_switch->last_case == NULL) {
-                               current_switch->first_case =
-                               current_switch->last_case  = &statement->case_label;
-                       } else {
-                               current_switch->last_case->next = &statement->case_label;
-                       }
+               errorf(pos, "case label does not reduce to an integer constant");
+       } else if (current_switch != NULL) {
+               /* Check for duplicate case values */
+               /* FIXME slow */
+               long const val = fold_constant(statement->case_label.expression);
+               for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
+                       expression_t const* const e = l->expression;
+                       if (e == NULL || !is_constant_expression(e) || fold_constant(e) != val)
+                               continue;
+
+                       errorf(pos, "duplicate case value");
+                       errorf(&l->base.source_position, "previously used here");
+                       break;
+               }
+
+               /* link all cases into the switch statement */
+               if (current_switch->last_case == NULL) {
+                       current_switch->first_case      = &statement->case_label;
                } else {
-                       errorf(&statement->base.source_position,
-                              "case label not within a switch statement");
+                       current_switch->last_case->next = &statement->case_label;
                }
+               current_switch->last_case = &statement->case_label;
+       } else {
+               errorf(pos, "case label not within a switch statement");
        }
-       statement->case_label.statement = parse_statement();
 
+       statement_t *const inner_stmt = parse_statement();
+       statement->case_label.statement = inner_stmt;
+       if (inner_stmt->kind == STATEMENT_DECLARATION) {
+               errorf(&inner_stmt->base.source_position, "declaration after case label");
+       }
+
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
@@ -7516,9 +8205,10 @@ static statement_t *parse_default_statement(void)
        eat(T_default);
 
        statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
-
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        expect(':');
        if (current_switch != NULL) {
                const case_label_statement_t *def_label = find_default_label(current_switch);
@@ -7528,25 +8218,34 @@ static statement_t *parse_default_statement(void)
                } else {
                        /* link all cases into the switch statement */
                        if (current_switch->last_case == NULL) {
-                               current_switch->first_case =
-                                       current_switch->last_case  = &statement->case_label;
+                               current_switch->first_case      = &statement->case_label;
                        } else {
                                current_switch->last_case->next = &statement->case_label;
                        }
+                       current_switch->last_case = &statement->case_label;
                }
        } else {
                errorf(&statement->base.source_position,
                        "'default' label not within a switch statement");
        }
-       statement->case_label.statement = parse_statement();
 
+       statement_t *const inner_stmt = parse_statement();
+       statement->case_label.statement = inner_stmt;
+       if (inner_stmt->kind == STATEMENT_DECLARATION) {
+               errorf(&inner_stmt->base.source_position, "declaration after default label");
+       }
+
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
 /**
  * Return the declaration for a given label symbol or create a new one.
+ *
+ * @param symbol  the symbol of the label
  */
 static declaration_t *get_label(symbol_t *symbol)
 {
@@ -7580,6 +8279,12 @@ static statement_t *parse_label_statement(void)
 
        declaration_t *label = get_label(symbol);
 
+       statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
+       statement->base.source_position = token.source_position;
+       statement->label.label          = label;
+
+       PUSH_PARENT(statement);
+
        /* if source position is already set then the label is defined twice,
         * otherwise it was just mentioned in a goto so far */
        if (label->source_position.input_name != NULL) {
@@ -7587,13 +8292,9 @@ static statement_t *parse_label_statement(void)
                       symbol, &label->source_position);
        } else {
                label->source_position = token.source_position;
+               label->init.statement  = statement;
        }
 
-       statement_t *statement = allocate_statement_zero(STATEMENT_LABEL);
-
-       statement->base.source_position = token.source_position;
-       statement->label.label          = label;
-
        eat(':');
 
        if (token.type == '}') {
@@ -7605,20 +8306,21 @@ static statement_t *parse_label_statement(void)
                        errorf(HERE, "label at end of compound statement");
                        statement->label.statement = create_invalid_statement();
                }
-               return statement;
+       } else if (token.type == ';') {
+               /* Eat an empty statement here, to avoid the warning about an empty
+                * statement after a label.  label:; is commonly used to have a label
+                * before a closing brace. */
+               statement->label.statement = create_empty_statement();
+               next_token();
        } else {
-               if (token.type == ';') {
-                       /* eat an empty statement here, to avoid the warning about an empty
-                        * after a label.  label:; is commonly used to have a label before
-                        * a }. */
-                       statement->label.statement = create_empty_statement();
-                       next_token();
-               } else {
-                       statement->label.statement = parse_statement();
+               statement_t *const inner_stmt = parse_statement();
+               statement->label.statement = inner_stmt;
+               if (inner_stmt->kind == STATEMENT_DECLARATION) {
+                       errorf(&inner_stmt->base.source_position, "declaration after label");
                }
        }
 
-       /* remember the labels's in a list for later checking */
+       /* remember the labels in a list for later checking */
        if (label_last == NULL) {
                label_first = &statement->label;
        } else {
@@ -7626,6 +8328,7 @@ static statement_t *parse_label_statement(void)
        }
        label_last = &statement->label;
 
+       POP_PARENT;
        return statement;
 }
 
@@ -7639,6 +8342,8 @@ static statement_t *parse_if(void)
        statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        expect('(');
        add_anchor_token(')');
        statement->ifs.condition = parse_expression();
@@ -7654,8 +8359,10 @@ static statement_t *parse_if(void)
                statement->ifs.false_statement = parse_statement();
        }
 
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
@@ -7669,6 +8376,8 @@ static statement_t *parse_switch(void)
        statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        expect('(');
        expression_t *const expr = parse_expression();
        type_t       *      type = skip_typeref(expr->base.type);
@@ -7692,8 +8401,10 @@ static statement_t *parse_switch(void)
                warningf(&statement->base.source_position, "switch has no default case");
        }
 
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
@@ -7718,6 +8429,8 @@ static statement_t *parse_while(void)
        statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        expect('(');
        add_anchor_token(')');
        statement->whiles.condition = parse_expression();
@@ -7726,8 +8439,10 @@ static statement_t *parse_while(void)
 
        statement->whiles.body = parse_loop_body(statement);
 
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
@@ -7739,9 +8454,10 @@ static statement_t *parse_do(void)
        eat(T_do);
 
        statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
-
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement)
+
        add_anchor_token(T_while);
        statement->do_while.body = parse_loop_body(statement);
        rem_anchor_token(T_while);
@@ -7754,8 +8470,10 @@ static statement_t *parse_do(void)
        expect(')');
        expect(';');
 
+       POP_PARENT;
        return statement;
 end_error:
+       POP_PARENT;
        return create_invalid_statement();
 }
 
@@ -7769,6 +8487,8 @@ static statement_t *parse_for(void)
        statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        int      top        = environment_top();
        scope_t *last_scope = scope;
        set_scope(&statement->fors.scope);
@@ -7816,9 +8536,11 @@ static statement_t *parse_for(void)
        set_scope(last_scope);
        environment_pop_to(top);
 
+       POP_PARENT;
        return statement;
 
 end_error:
+       POP_PARENT;
        rem_anchor_token(')');
        assert(scope == &statement->fors.scope);
        set_scope(last_scope);
@@ -7936,7 +8658,8 @@ end_error:
 /**
  * Check if a given declaration represents a local variable.
  */
-static bool is_local_var_declaration(const declaration_t *declaration) {
+static bool is_local_var_declaration(const declaration_t *declaration)
+{
        switch ((storage_class_tag_t) declaration->storage_class) {
        case STORAGE_CLASS_AUTO:
        case STORAGE_CLASS_REGISTER: {
@@ -7955,7 +8678,8 @@ static bool is_local_var_declaration(const declaration_t *declaration) {
 /**
  * Check if a given declaration represents a variable.
  */
-static bool is_var_declaration(const declaration_t *declaration) {
+static bool is_var_declaration(const declaration_t *declaration)
+{
        if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
                return false;
 
@@ -8090,7 +8814,8 @@ end_error:
  * Parse a microsoft __try { } __finally { } or
  * __try{ } __except() { }
  */
-static statement_t *parse_ms_try_statment(void) {
+static statement_t *parse_ms_try_statment(void)
+{
        statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
 
        statement->base.source_position  = token.source_position;
@@ -8130,6 +8855,15 @@ end_error:
        return create_invalid_statement();
 }
 
+static statement_t *parse_empty_statement(void)
+{
+       if (warning.empty_statement) {
+               warningf(HERE, "statement is empty");
+       }
+       eat(';');
+       return create_empty_statement();
+}
+
 /**
  * Parse a statement.
  * There's also parse_statement() which additionally checks for
@@ -8141,91 +8875,23 @@ static statement_t *intern_parse_statement(void)
 
        /* declaration or statement */
        add_anchor_token(';');
-       switch(token.type) {
-       case T_asm:
-               statement = parse_asm_statement();
-               break;
-
-       case T_case:
-               statement = parse_case_statement();
-               break;
-
-       case T_default:
-               statement = parse_default_statement();
-               break;
-
-       case '{':
-               statement = parse_compound_statement(false);
-               break;
-
-       case T_if:
-               statement = parse_if ();
-               break;
-
-       case T_switch:
-               statement = parse_switch();
-               break;
-
-       case T_while:
-               statement = parse_while();
-               break;
-
-       case T_do:
-               statement = parse_do();
-               break;
-
-       case T_for:
-               statement = parse_for();
-               break;
-
-       case T_goto:
-               statement = parse_goto();
-               break;
-
-       case T_continue:
-               statement = parse_continue();
-               break;
-
-       case T_break:
-               statement = parse_break();
-               break;
-
-       case T___leave:
-               statement = parse_leave();
-               break;
-
-       case T_return:
-               statement = parse_return();
-               break;
-
-       case ';':
-               if (warning.empty_statement) {
-                       warningf(HERE, "statement is empty");
-               }
-               statement = create_empty_statement();
-               next_token();
-               break;
-
+       switch (token.type) {
        case T_IDENTIFIER:
                if (look_ahead(1)->type == ':') {
                        statement = parse_label_statement();
-                       break;
-               }
-
-               if (is_typedef_symbol(token.v.symbol)) {
+               } else if (is_typedef_symbol(token.v.symbol)) {
                        statement = parse_declaration_statement();
-                       break;
+               } else {
+                       statement = parse_expression_statement();
                }
-
-               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 */
+               /* 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__);
+               } while (token.type == T___extension__);
                statement = parse_statement();
                break;
 
@@ -8233,13 +8899,23 @@ static statement_t *intern_parse_statement(void)
                statement = parse_declaration_statement();
                break;
 
-       case T___try:
-               statement = parse_ms_try_statment();
-               break;
-
-       default:
-               statement = parse_expression_statement();
-               break;
+       case ';':        statement = parse_empty_statement();         break;
+       case '{':        statement = parse_compound_statement(false); break;
+       case T___leave:  statement = parse_leave();                   break;
+       case T___try:    statement = parse_ms_try_statment();         break;
+       case T_asm:      statement = parse_asm_statement();           break;
+       case T_break:    statement = parse_break();                   break;
+       case T_case:     statement = parse_case_statement();          break;
+       case T_continue: statement = parse_continue();                break;
+       case T_default:  statement = parse_default_statement();       break;
+       case T_do:       statement = parse_do();                      break;
+       case T_for:      statement = parse_for();                     break;
+       case T_goto:     statement = parse_goto();                    break;
+       case T_if:       statement = parse_if ();                     break;
+       case T_return:   statement = parse_return();                  break;
+       case T_switch:   statement = parse_switch();                  break;
+       case T_while:    statement = parse_while();                   break;
+       default:         statement = parse_expression_statement();    break;
        }
        rem_anchor_token(';');
 
@@ -8276,9 +8952,10 @@ static statement_t *parse_statement(void)
 static statement_t *parse_compound_statement(bool inside_expression_statement)
 {
        statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
-
        statement->base.source_position = token.source_position;
 
+       PUSH_PARENT(statement);
+
        eat('{');
        add_anchor_token('}');
 
@@ -8288,7 +8965,8 @@ static statement_t *parse_compound_statement(bool inside_expression_statement)
 
        statement_t *last_statement = NULL;
 
-       while(token.type != '}' && token.type != T_EOF) {
+       bool only_decls_so_far = true;
+       while (token.type != '}' && token.type != T_EOF) {
                statement_t *sub_statement = intern_parse_statement();
                if (is_invalid_statement(sub_statement)) {
                        /* an error occurred. if we are at an anchor, return */
@@ -8297,13 +8975,22 @@ static statement_t *parse_compound_statement(bool inside_expression_statement)
                        continue;
                }
 
+               if (warning.declaration_after_statement) {
+                       if (sub_statement->kind != STATEMENT_DECLARATION) {
+                               only_decls_so_far = false;
+                       } else if (!only_decls_so_far) {
+                               warningf(&sub_statement->base.source_position,
+                                        "ISO C90 forbids mixed declarations and code");
+                       }
+               }
+
                if (last_statement != NULL) {
                        last_statement->base.next = sub_statement;
                } else {
                        statement->compound.statements = sub_statement;
                }
 
-               while(sub_statement->base.next != NULL)
+               while (sub_statement->base.next != NULL)
                        sub_statement = sub_statement->base.next;
 
                last_statement = sub_statement;
@@ -8341,6 +9028,7 @@ end_error:
        set_scope(last_scope);
        environment_pop_to(top);
 
+       POP_PARENT;
        return statement;
 }
 
@@ -8373,8 +9061,9 @@ static void check_unused_globals(void)
                return;
 
        for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
-               if (decl->used                ||
-                   decl->modifiers & DM_USED ||
+               if (decl->used                  ||
+                   decl->modifiers & DM_UNUSED ||
+                   decl->modifiers & DM_USED   ||
                    decl->storage_class != STORAGE_CLASS_STATIC)
                        continue;
 
@@ -8419,22 +9108,32 @@ end_error:;
  */
 static void parse_translation_unit(void)
 {
-       while(token.type != T_EOF) {
-               switch (token.type) {
-                       case ';':
-                               /* TODO error in strict mode */
-                               warningf(HERE, "stray ';' outside of function");
-                               next_token();
-                               break;
+       for (;;) switch (token.type) {
+               DECLARATION_START
+               case T_IDENTIFIER:
+               case T___extension__:
+                       parse_external_declaration();
+                       break;
 
-                       case T_asm:
-                               parse_global_asm();
-                               break;
+               case T_asm:
+                       parse_global_asm();
+                       break;
 
-                       default:
-                               parse_external_declaration();
-                               break;
-               }
+               case T_EOF:
+                       return;
+
+               case ';':
+                       /* TODO error in strict mode */
+                       warningf(HERE, "stray ';' outside of function");
+                       next_token();
+                       break;
+
+               default:
+                       errorf(HERE, "stray %K outside of function", &token);
+                       if (token.type == '(' || token.type == '{' || token.type == '[')
+                               eat_until_matching_token(token.type);
+                       next_token();
+                       break;
        }
 }