+union type_t {
+ type_kind_t kind;
+ type_base_t base;
+ atomic_type_t atomic;
+ pointer_type_t pointer;
+ reference_type_t reference;
+ array_type_t array;
+ function_type_t function;
+ compound_type_t compound;
+ enum_type_t enumt;
+ typedef_type_t typedeft;
+ typeof_type_t typeoft;
+};
+
+typedef struct atomic_type_properties_t atomic_type_properties_t;
+struct atomic_type_properties_t {
+ unsigned size; /**< type size in bytes */
+ unsigned alignment; /**< type alignment in bytes */
+ /** some ABIs are broken and require an alignment different from the
+ * recommended/best alignment inside structs. Fixing ABIs is difficult
+ * so people rather stick with the wrong values for compatibility.
+ * (double type on x86 System V ABI)
+ */
+ unsigned struct_alignment;
+ unsigned flags; /**< type flags from atomic_type_flag_t */
+ unsigned rank; /**< integer conversion rank */
+};
+
+extern atomic_type_properties_t atomic_type_properties[ATOMIC_TYPE_LAST+1];
+extern atomic_type_properties_t pointer_properties;
+
+/** The default calling convention for functions. */
+extern cc_kind_t default_calling_convention;
+
+type_t *make_atomic_type(atomic_type_kind_t type, type_qualifiers_t qualifiers);
+type_t *make_complex_type(atomic_type_kind_t type, type_qualifiers_t qualifiers);
+type_t *make_imaginary_type(atomic_type_kind_t type, type_qualifiers_t qualifiers);
+type_t *make_pointer_type(type_t *points_to, type_qualifiers_t qualifiers);
+type_t *make_reference_type(type_t *refers_to);
+type_t *make_based_pointer_type(type_t *points_to,
+ type_qualifiers_t qualifiers, variable_t *variable);
+type_t *make_array_type(type_t *element_type, size_t size,
+ type_qualifiers_t qualifiers);
+function_parameter_t *allocate_parameter(type_t*);
+
+/**
+ * Duplicates a type.
+ *
+ * @param type The type to copy.
+ * @return A copy of the type.
+ *
+ * @note This does not produce a deep copy!
+ */
+type_t *duplicate_type(const type_t *type);
+
+type_t *identify_new_type(type_t *type);
+
+static inline bool is_typeref(const type_t *type)
+{
+ return type->kind == TYPE_TYPEDEF || type->kind == TYPE_TYPEOF;
+}
+
+static inline bool is_type_atomic(const type_t *type, atomic_type_kind_t atype)
+{
+ assert(!is_typeref(type));
+
+ if(type->kind != TYPE_ATOMIC)
+ return false;
+ const atomic_type_t *atomic_type = &type->atomic;
+
+ return atomic_type->akind == atype;
+}
+
+static inline bool is_type_void(type_t const *const type)
+{
+ return is_type_atomic(type, ATOMIC_TYPE_VOID);
+}
+
+static inline bool is_type_pointer(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_POINTER;
+}
+
+static inline bool is_type_reference(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_REFERENCE;
+}
+
+static inline bool is_type_array(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_ARRAY;
+}
+
+static inline bool is_type_function(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_FUNCTION;
+}
+
+static inline bool is_type_union(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_COMPOUND_UNION;
+}
+
+static inline bool is_type_struct(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_COMPOUND_STRUCT;
+}
+
+static inline bool is_type_compound(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind == TYPE_COMPOUND_STRUCT
+ || type->kind == TYPE_COMPOUND_UNION;
+}
+
+static inline bool is_type_valid(const type_t *type)
+{
+ assert(!is_typeref(type));
+ return type->kind != TYPE_ERROR;
+}
+
+/**
+ * return integer conversion rank of an atomic type kind
+ */
+static inline unsigned get_akind_rank(atomic_type_kind_t akind)
+{
+ return atomic_type_properties[akind].rank;
+}
+
+/**
+ * Allocate a type node of given kind and initialize all
+ * fields with zero.
+ *
+ * @param kind type kind to allocate
+ */
+type_t *allocate_type_zero(type_kind_t kind);
+
+/**
+ * Creates a return_type (func)(void) function type if not
+ * already exists.
+ *
+ * @param return_type the return type
+ */
+type_t *make_function_0_type(type_t *return_type,
+ decl_modifiers_t modifiers);
+
+/**
+ * Creates a return_type (func)(argument_type) function type if not
+ * already exists.
+ *
+ * @param return_type the return type
+ * @param argument_type the argument type
+ */
+type_t *make_function_1_type(type_t *return_type, type_t *argument_type1,
+ decl_modifiers_t modifiers);
+
+
+/**
+ * Creates a return_type (func)(argument_type1,argument_type2) function type
+ * if not already exists.
+ */
+type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
+ type_t *argument_type2,
+ decl_modifiers_t modifiers);
+
+/**
+ * Creates a return_type (func)(argument_type, ...) function type if not
+ * already exists.
+ *
+ * @param return_type the return type
+ * @param argument_type the argument type
+ */
+type_t *make_function_1_type_variadic(type_t *return_type,
+ type_t *argument_type,
+ decl_modifiers_t modifiers);
+
+/**
+ * Create a function type with n parameters
+ */
+type_t *make_function_type(type_t *return_type, int n_types,
+ type_t *const *argument_types,
+ decl_modifiers_t modifiers);