X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=type.c;h=4cf3d74888ad8320a56b2fc071043e49c2c561c5;hb=10ddb641ca4f0624dbeb3f300479e29c3ccedefb;hp=8a6486ddfc7d0104997858ad353ce4ee36ecb845;hpb=6fe9dcaa0774eaea804b563d5c7b6e656ce41734;p=cparser

diff --git a/type.c b/type.c
index 8a6486d..4cf3d74 100644
--- a/type.c
+++ b/type.c
@@ -7,12 +7,13 @@
 #include "adt/error.h"
 
 static struct obstack   _type_obst;
-struct obstack         *type_obst = &_type_obst;
 static FILE            *out;
-static int              type_visited = 0;
+struct obstack         *type_obst                 = &_type_obst;
+static int              type_visited              = 0;
+static bool             print_implicit_array_size = true;
 
-static void intern_print_type_pre(type_t *type);
-static void intern_print_type_post(type_t *type);
+static void intern_print_type_pre(const type_t *type, bool top);
+static void intern_print_type_post(const type_t *type, bool top);
 
 void init_types(void)
 {
@@ -41,13 +42,18 @@ void print_type_qualifiers(type_qualifiers_t qualifiers)
 	if(qualifiers & TYPE_QUALIFIER_RESTRICT) fputs("restrict ", out);
 }
 
+/**
+ * Prints the name of a atomic type.
+ *
+ * @param type  The type.
+ */
 static
 void print_atomic_type(const atomic_type_t *type)
 {
 	print_type_qualifiers(type->type.qualifiers);
 
 	const char *s;
-	switch(type->atype) {
+	switch(type->akind) {
 	case ATOMIC_TYPE_INVALID:     s = "INVALIDATOMIC";      break;
 	case ATOMIC_TYPE_VOID:        s = "void";               break;
 	case ATOMIC_TYPE_BOOL:        s = "_Bool";              break;
@@ -70,27 +76,41 @@ void print_atomic_type(const atomic_type_t *type)
 	fputs(s, out);
 }
 
-static void print_function_type_pre(const function_type_t *type)
+/**
+ * Print the first part (the prefix) of a type.
+ *
+ * @param type   The type to print.
+ * @param top    true, if this is the top type, false if it's an embedded type.
+ */
+static void print_function_type_pre(const function_type_t *type, bool top)
 {
 	print_type_qualifiers(type->type.qualifiers);
 
-	intern_print_type_pre(type->return_type);
+	intern_print_type_pre(type->return_type, false);
 
-	/* TODO: don't emit braces if we're the toplevel type... */
-	fputc('(', out);
+	/* don't emit braces if we're the toplevel type... */
+	if(!top)
+		fputc('(', out);
 }
 
+/**
+ * Print the second part (the postfix) of a type.
+ *
+ * @param type   The type to print.
+ * @param top    true, if this is the top type, false if it's an embedded type.
+ */
 static void print_function_type_post(const function_type_t *type,
-                                     const context_t *context)
+                                     const scope_t *scope, bool top)
 {
-	/* TODO: don't emit braces if we're the toplevel type... */
-	intern_print_type_post(type->return_type);
-	fputc(')', out);
+	intern_print_type_post(type->return_type, false);
+	/* don't emit braces if we're the toplevel type... */
+	if(!top)
+		fputc(')', out);
 
 	fputc('(', out);
 
-	int                 first     = 1;
-	if(context == NULL) {
+	int first = 1;
+	if(scope == NULL) {
 		function_parameter_t *parameter = type->parameters;
 		for( ; parameter != NULL; parameter = parameter->next) {
 			if(first) {
@@ -101,7 +121,7 @@ static void print_function_type_post(const function_type_t *type,
 			print_type(parameter->type);
 		}
 	} else {
-		declaration_t *parameter = context->declarations;
+		declaration_t *parameter = scope->declarations;
 		for( ; parameter != NULL; parameter = parameter->next) {
 			if(first) {
 				first = 0;
@@ -109,7 +129,7 @@ static void print_function_type_post(const function_type_t *type,
 				fputs(", ", out);
 			}
 			print_type_ext(parameter->type, parameter->symbol,
-			               &parameter->context);
+			               &parameter->scope);
 		}
 	}
 	if(type->variadic) {
@@ -126,23 +146,43 @@ static void print_function_type_post(const function_type_t *type,
 	fputc(')', out);
 }
 
+/**
+ * Prints the prefix part of a pointer type.
+ *
+ * @param type   The pointer type.
+ */
 static void print_pointer_type_pre(const pointer_type_t *type)
 {
-	intern_print_type_pre(type->points_to);
+	intern_print_type_pre(type->points_to, false);
 	fputs("*", out);
 	print_type_qualifiers(type->type.qualifiers);
 }
 
+/**
+ * Prints the postfix part of a pointer type.
+ *
+ * @param type   The pointer type.
+ */
 static void print_pointer_type_post(const pointer_type_t *type)
 {
-	intern_print_type_post(type->points_to);
+	intern_print_type_post(type->points_to, false);
 }
 
+/**
+ * Prints the prefix part of an array type.
+ *
+ * @param type   The array type.
+ */
 static void print_array_type_pre(const array_type_t *type)
 {
-	intern_print_type_pre(type->element_type);
+	intern_print_type_pre(type->element_type, false);
 }
 
+/**
+ * Prints the postfix part of an array type.
+ *
+ * @param type   The array type.
+ */
 static void print_array_type_post(const array_type_t *type)
 {
 	fputc('[', out);
@@ -150,13 +190,31 @@ static void print_array_type_post(const array_type_t *type)
 		fputs("static ", out);
 	}
 	print_type_qualifiers(type->type.qualifiers);
-	if(type->size != NULL) {
-		print_expression(type->size);
+	if(type->size_expression != NULL
+			&& (print_implicit_array_size || !type->has_implicit_size)) {
+		print_expression(type->size_expression);
 	}
 	fputc(']', out);
-	intern_print_type_post(type->element_type);
+	intern_print_type_post(type->element_type, false);
+}
+
+/**
+ * Prints the postfix part of a bitfield type.
+ *
+ * @param type   The array type.
+ */
+static void print_bitfield_type_post(const bitfield_type_t *type)
+{
+	fputs(" : ", out);
+	print_expression(type->size);
+	intern_print_type_post(type->base, false);
 }
 
+/**
+ * Prints an enum definition.
+ *
+ * @param declaration  The enum's type declaration.
+ */
 void print_enum_definition(const declaration_t *declaration)
 {
 	fputs("{\n", out);
@@ -181,6 +239,11 @@ void print_enum_definition(const declaration_t *declaration)
 	fputs("}", out);
 }
 
+/**
+ * Prints an enum type.
+ *
+ * @param type  The enum type.
+ */
 static void print_type_enum(const enum_type_t *type)
 {
 	print_type_qualifiers(type->type.qualifiers);
@@ -195,12 +258,17 @@ static void print_type_enum(const enum_type_t *type)
 	}
 }
 
+/**
+ * Print the compound part of a compound type.
+ *
+ * @param declaration  The declaration of the compound type.
+ */
 void print_compound_definition(const declaration_t *declaration)
 {
 	fputs("{\n", out);
 	change_indent(1);
 
-	declaration_t *iter = declaration->context.declarations;
+	declaration_t *iter = declaration->scope.declarations;
 	for( ; iter != NULL; iter = iter->next) {
 		print_indent();
 		print_declaration(iter);
@@ -212,14 +280,19 @@ void print_compound_definition(const declaration_t *declaration)
 	fputs("}", out);
 }
 
+/**
+ * Prints a compound type.
+ *
+ * @param type  The compound type.
+ */
 static void print_compound_type(const compound_type_t *type)
 {
 	print_type_qualifiers(type->type.qualifiers);
 
-	if(type->type.type == TYPE_COMPOUND_STRUCT) {
+	if(type->type.kind == TYPE_COMPOUND_STRUCT) {
 		fputs("struct ", out);
 	} else {
-		assert(type->type.type == TYPE_COMPOUND_UNION);
+		assert(type->type.kind == TYPE_COMPOUND_UNION);
 		fputs("union ", out);
 	}
 
@@ -232,12 +305,23 @@ static void print_compound_type(const compound_type_t *type)
 	}
 }
 
-static void print_typedef_type_pre(typedef_type_t *type)
+/**
+ * Prints the prefix part of a typedef type.
+ *
+ * @param type   The typedef type.
+ */
+static void print_typedef_type_pre(const typedef_type_t *const type)
 {
+	print_type_qualifiers(type->type.qualifiers);
 	fputs(type->declaration->symbol->string, out);
 }
 
-static void print_typeof_type_pre(typeof_type_t *type)
+/**
+ * Prints the prefix part of a typeof type.
+ *
+ * @param type   The typeof type.
+ */
+static void print_typeof_type_pre(const typeof_type_t *const type)
 {
 	fputs("typeof(", out);
 	if(type->expression != NULL) {
@@ -249,11 +333,19 @@ static void print_typeof_type_pre(typeof_type_t *type)
 	fputc(')', out);
 }
 
-static void intern_print_type_pre(type_t *type)
+/**
+ * Prints the prefix part of a type.
+ *
+ * @param type   The type.
+ * @param top    true if we print the toplevel type, false else.
+ */
+static void intern_print_type_pre(const type_t *const type, const bool top)
 {
-	switch(type->type) {
+	switch(type->kind) {
+	case TYPE_ERROR:
+		fputs("<error>", out);
 	case TYPE_INVALID:
-		fputs("invalid", out);
+		fputs("<invalid>", out);
 		return;
 	case TYPE_ENUM:
 		print_type_enum(&type->enumt);
@@ -269,11 +361,14 @@ static void intern_print_type_pre(type_t *type)
 		fputs(type->builtin.symbol->string, out);
 		return;
 	case TYPE_FUNCTION:
-		print_function_type_pre(&type->function);
+		print_function_type_pre(&type->function, top);
 		return;
 	case TYPE_POINTER:
 		print_pointer_type_pre(&type->pointer);
 		return;
+	case TYPE_BITFIELD:
+		intern_print_type_pre(type->bitfield.base, top);
+		return;
 	case TYPE_ARRAY:
 		print_array_type_pre(&type->array);
 		return;
@@ -287,11 +382,17 @@ static void intern_print_type_pre(type_t *type)
 	fputs("unknown", out);
 }
 
-static void intern_print_type_post(type_t *type)
+/**
+ * Prints the postfix part of a type.
+ *
+ * @param type   The type.
+ * @param top    true if we print the toplevel type, false else.
+ */
+static void intern_print_type_post(const type_t *const type, const bool top)
 {
-	switch(type->type) {
+	switch(type->kind) {
 	case TYPE_FUNCTION:
-		print_function_type_post(&type->function, NULL);
+		print_function_type_post(&type->function, NULL, top);
 		return;
 	case TYPE_POINTER:
 		print_pointer_type_post(&type->pointer);
@@ -299,6 +400,10 @@ static void intern_print_type_post(type_t *type)
 	case TYPE_ARRAY:
 		print_array_type_post(&type->array);
 		return;
+	case TYPE_BITFIELD:
+		print_bitfield_type_post(&type->bitfield);
+		return;
+	case TYPE_ERROR:
 	case TYPE_INVALID:
 	case TYPE_ATOMIC:
 	case TYPE_ENUM:
@@ -311,34 +416,44 @@ static void intern_print_type_post(type_t *type)
 	}
 }
 
-void print_type(type_t *type)
+/**
+ * Prints a type.
+ *
+ * @param type   The type.
+ */
+void print_type(const type_t *const type)
 {
 	print_type_ext(type, NULL, NULL);
 }
 
-void print_type_ext(type_t *type, const symbol_t *symbol,
-                    const context_t *context)
+void print_type_ext(const type_t *const type, const symbol_t *symbol,
+                    const scope_t *scope)
 {
 	if(type == NULL) {
 		fputs("nil type", out);
 		return;
 	}
 
-	intern_print_type_pre(type);
+	intern_print_type_pre(type, true);
 	if(symbol != NULL) {
 		fputc(' ', out);
 		fputs(symbol->string, out);
 	}
-	if(type->type == TYPE_FUNCTION) {
-		print_function_type_post((const function_type_t*) type, context);
+	if(type->kind == TYPE_FUNCTION) {
+		print_function_type_post(&type->function, scope, true);
 	} else {
-		intern_print_type_post(type);
+		intern_print_type_post(type, true);
 	}
 }
 
-static size_t get_type_size(type_t *type)
+/**
+ * Return the size of a type AST node.
+ *
+ * @param type  The type.
+ */
+static size_t get_type_size(const type_t *type)
 {
-	switch(type->type) {
+	switch(type->kind) {
 	case TYPE_ATOMIC:          return sizeof(atomic_type_t);
 	case TYPE_COMPOUND_STRUCT:
 	case TYPE_COMPOUND_UNION:  return sizeof(compound_type_t);
@@ -349,16 +464,22 @@ static size_t get_type_size(type_t *type)
 	case TYPE_BUILTIN:         return sizeof(builtin_type_t);
 	case TYPE_TYPEDEF:         return sizeof(typedef_type_t);
 	case TYPE_TYPEOF:          return sizeof(typeof_type_t);
+	case TYPE_BITFIELD:        return sizeof(bitfield_type_t);
+	case TYPE_ERROR:           panic("error type found");
 	case TYPE_INVALID:         panic("invalid type found");
 	}
 	panic("unknown type found");
 }
 
 /**
- * duplicates a type
- * note that this does not produce a deep copy!
+ * 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(type_t *type)
+type_t *duplicate_type(const type_t *type)
 {
 	size_t size = get_type_size(type);
 
@@ -368,6 +489,12 @@ type_t *duplicate_type(type_t *type)
 	return copy;
 }
 
+/**
+ * Returns the unqualified type of a given type.
+ *
+ * @param type  The type.
+ * @returns The unqualified type.
+ */
 type_t *get_unqualified_type(type_t *type)
 {
 	if(type->base.qualifiers == TYPE_QUALIFIER_NONE)
@@ -384,22 +511,34 @@ type_t *get_unqualified_type(type_t *type)
 	return result;
 }
 
+/**
+ * Check if a type is valid.
+ *
+ * @param type  The type to check.
+ * @return true if type represents a valid type.
+ */
 bool type_valid(const type_t *type)
 {
-	return type->type != TYPE_INVALID;
+	return type->kind != TYPE_INVALID;
 }
 
+/**
+ * Returns true if the given type is an integer type.
+ *
+ * @param type  The type to check.
+ * @return True if type is an integer type.
+ */
 bool is_type_integer(const type_t *type)
 {
 	assert(!is_typeref(type));
 
-	if(type->type == TYPE_ENUM)
+	if(type->kind == TYPE_ENUM)
 		return true;
 
-	if(type->type != TYPE_ATOMIC)
+	if(type->kind != TYPE_ATOMIC)
 		return false;
 
-	switch(type->atomic.atype) {
+	switch(type->atomic.akind) {
 	case ATOMIC_TYPE_BOOL:
 	case ATOMIC_TYPE_CHAR:
 	case ATOMIC_TYPE_SCHAR:
@@ -418,14 +557,20 @@ bool is_type_integer(const type_t *type)
 	}
 }
 
-bool is_type_floating(const type_t *type)
+/**
+ * Returns true if the given type is an floating point type.
+ *
+ * @param type  The type to check.
+ * @return True if type is a floating point type.
+ */
+bool is_type_float(const type_t *type)
 {
 	assert(!is_typeref(type));
 
-	if(type->type != TYPE_ATOMIC)
+	if(type->kind != TYPE_ATOMIC)
 		return false;
 
-	switch(type->atomic.atype) {
+	switch(type->atomic.akind) {
 	case ATOMIC_TYPE_FLOAT:
 	case ATOMIC_TYPE_DOUBLE:
 	case ATOMIC_TYPE_LONG_DOUBLE:
@@ -443,18 +588,24 @@ bool is_type_floating(const type_t *type)
 	}
 }
 
+/**
+ * Returns true if the given type is a signed type.
+ *
+ * @param type  The type to check.
+ * @return True if type is a signed type.
+ */
 bool is_type_signed(const type_t *type)
 {
 	assert(!is_typeref(type));
 
 	/* enum types are int for now */
-	if(type->type == TYPE_ENUM)
+	if(type->kind == TYPE_ENUM)
 		return true;
 
-	if(type->type != TYPE_ATOMIC)
+	if(type->kind != TYPE_ATOMIC)
 		return false;
 
-	switch(type->atomic.atype) {
+	switch(type->atomic.akind) {
 	case ATOMIC_TYPE_CHAR:
 	case ATOMIC_TYPE_SCHAR:
 	case ATOMIC_TYPE_SHORT:
@@ -482,8 +633,9 @@ bool is_type_signed(const type_t *type)
 	case ATOMIC_TYPE_ULONGLONG:
 		return false;
 
-	case ATOMIC_TYPE_INVALID:
 	case ATOMIC_TYPE_VOID:
+	case ATOMIC_TYPE_INVALID:
+	case ATOMIC_TYPE_LAST:
 		return false;
 	}
 
@@ -491,51 +643,83 @@ bool is_type_signed(const type_t *type)
 	return false;
 }
 
+/**
+ * Returns true if the given type represents an arithmetic type.
+ *
+ * @param type  The type to check.
+ * @return True if type represents an arithmetic type.
+ */
 bool is_type_arithmetic(const type_t *type)
 {
 	assert(!is_typeref(type));
 
-	if(is_type_integer(type) || is_type_floating(type))
-		return 1;
+	if(type->kind == TYPE_BITFIELD)
+		return true;
+
+	if(is_type_integer(type) || is_type_float(type))
+		return true;
 
-	return 0;
+	return false;
 }
 
+/**
+ * Returns true if the given type represents a scalar type.
+ *
+ * @param type  The type to check.
+ * @return True if type represents a scalar type.
+ */
 bool is_type_scalar(const type_t *type)
 {
 	assert(!is_typeref(type));
 
-	if(type->type == TYPE_POINTER)
-		return 1;
+	switch (type->kind) {
+		case TYPE_POINTER: return true;
+		case TYPE_BUILTIN: return is_type_scalar(type->builtin.real_type);
+		default:            break;
+	}
 
 	return is_type_arithmetic(type);
 }
 
+/**
+ * Check if a given type is incomplete.
+ *
+ * @param type  The type to check.
+ * @return True if the given type is incomplete (ie. just forward).
+ */
 bool is_type_incomplete(const type_t *type)
 {
 	assert(!is_typeref(type));
 
-	switch(type->type) {
+	switch(type->kind) {
 	case TYPE_COMPOUND_STRUCT:
 	case TYPE_COMPOUND_UNION: {
 		const compound_type_t *compound_type = &type->compound;
 		declaration_t         *declaration   = compound_type->declaration;
 		return !declaration->init.is_defined;
 	}
+	case TYPE_ENUM: {
+		const enum_type_t *enum_type   = &type->enumt;
+		declaration_t     *declaration = enum_type->declaration;
+		return !declaration->init.is_defined;
+	}
+	case TYPE_BITFIELD:
 	case TYPE_FUNCTION:
 		return true;
 
 	case TYPE_ARRAY:
-		return type->array.size == NULL;
+		return type->array.size_expression == NULL;
 
 	case TYPE_ATOMIC:
+		return type->atomic.akind == ATOMIC_TYPE_VOID;
+
 	case TYPE_POINTER:
-	case TYPE_ENUM:
+	case TYPE_BUILTIN:
+	case TYPE_ERROR:
 		return false;
 
 	case TYPE_TYPEDEF:
 	case TYPE_TYPEOF:
-	case TYPE_BUILTIN:
 		panic("is_type_incomplete called without typerefs skipped");
 	case TYPE_INVALID:
 		break;
@@ -544,10 +728,15 @@ bool is_type_incomplete(const type_t *type)
 	panic("invalid type found");
 }
 
+/**
+ * Check if two function types are compatible.
+ */
 static bool function_types_compatible(const function_type_t *func1,
                                       const function_type_t *func2)
 {
-	if(!types_compatible(func1->return_type, func2->return_type))
+	const type_t* const ret1 = skip_typeref(func1->return_type);
+	const type_t* const ret2 = skip_typeref(func2->return_type);
+	if (!types_compatible(ret1, ret2))
 		return false;
 
 	/* can parameters be compared? */
@@ -580,6 +769,9 @@ static bool function_types_compatible(const function_type_t *func1,
 	return true;
 }
 
+/**
+ * Check if two array types are compatible.
+ */
 static bool array_types_compatible(const array_type_t *array1,
                                    const array_type_t *array2)
 {
@@ -588,14 +780,15 @@ static bool array_types_compatible(const array_type_t *array1,
 	if(!types_compatible(element_type1, element_type2))
 		return false;
 
-	if(array1->size != NULL && array2->size != NULL) {
-		/* TODO: check if size expression evaulate to the same value
-		 * if they are constant */
-	}
+	if(!array1->size_constant || !array2->size_constant)
+		return true;
 
-	return true;
+	return array1->size == array2->size;
 }
 
+/**
+ * Check if two types are compatible.
+ */
 bool types_compatible(const type_t *type1, const type_t *type2)
 {
 	assert(!is_typeref(type1));
@@ -607,19 +800,23 @@ bool types_compatible(const type_t *type1, const type_t *type2)
 
 	if(type1->base.qualifiers != type2->base.qualifiers)
 		return false;
-	if(type1->type != type2->type)
+	if(type1->kind != type2->kind)
 		return false;
 
-	switch(type1->type) {
+	switch(type1->kind) {
 	case TYPE_FUNCTION:
 		return function_types_compatible(&type1->function, &type2->function);
 	case TYPE_ATOMIC:
-		return type1->atomic.atype == type2->atomic.atype;
+		return type1->atomic.akind == type2->atomic.akind;
 	case TYPE_ARRAY:
 		return array_types_compatible(&type1->array, &type2->array);
-	case TYPE_POINTER:
-		return types_compatible(type1->pointer.points_to,
-		                        type2->pointer.points_to);
+
+	case TYPE_POINTER: {
+		const type_t *const to1 = skip_typeref(type1->pointer.points_to);
+		const type_t *const to2 = skip_typeref(type2->pointer.points_to);
+		return types_compatible(to1, to2);
+	}
+
 	case TYPE_COMPOUND_STRUCT:
 	case TYPE_COMPOUND_UNION:
 	case TYPE_ENUM:
@@ -627,6 +824,14 @@ bool types_compatible(const type_t *type1, const type_t *type2)
 		/* TODO: not implemented */
 		break;
 
+	case TYPE_BITFIELD:
+		/* not sure if this makes sense or is even needed, implement it if you
+		 * really need it! */
+		panic("type compatibility check for bitfield type");
+
+	case TYPE_ERROR:
+		/* Hmm, the error type should be compatible to all other types */
+		return true;
 	case TYPE_INVALID:
 		panic("invalid type found in compatible types");
 	case TYPE_TYPEDEF:
@@ -638,23 +843,33 @@ bool types_compatible(const type_t *type1, const type_t *type2)
 	return false;
 }
 
+/**
+ * Check if two pointer types are compatible.
+ */
 bool pointers_compatible(const type_t *type1, const type_t *type2)
 {
 	assert(!is_typeref(type1));
 	assert(!is_typeref(type2));
 
-	assert(type1->type == TYPE_POINTER);
-	assert(type2->type == TYPE_POINTER);
+	assert(type1->kind == TYPE_POINTER);
+	assert(type2->kind == TYPE_POINTER);
+	(void) type1;
+	(void) type2;
 	/* TODO */
 	return true;
 }
 
+/**
+ * Skip all typerefs and return the underlying type.
+ */
 type_t *skip_typeref(type_t *type)
 {
-	unsigned qualifiers = type->base.qualifiers;
+	unsigned qualifiers = TYPE_QUALIFIER_NONE;
 
-	while(1) {
-		switch(type->type) {
+	while(true) {
+		switch(type->kind) {
+		case TYPE_ERROR:
+			return type;
 		case TYPE_TYPEDEF: {
 			qualifiers |= type->base.qualifiers;
 			const typedef_type_t *typedef_type = &type->typedeft;
@@ -670,26 +885,33 @@ type_t *skip_typeref(type_t *type)
 			if(typeof_type->typeof_type != NULL) {
 				type = typeof_type->typeof_type;
 			} else {
-				type = typeof_type->expression->base.datatype;
+				type = typeof_type->expression->base.type;
 			}
 			continue;
 		}
-		case TYPE_BUILTIN: {
-			const builtin_type_t *builtin_type = &type->builtin;
-			type = builtin_type->real_type;
-			continue;
-		}
 		default:
 			break;
 		}
 		break;
 	}
 
-	return type;
-}
+	if (qualifiers != TYPE_QUALIFIER_NONE) {
+		type_t *const copy     = duplicate_type(type);
+		copy->base.qualifiers |= qualifiers;
 
+		type = typehash_insert(copy);
+		if (type != copy) {
+			obstack_free(type_obst, copy);
+		}
+	}
 
+	return type;
+}
 
+/**
+ * Hash the given type and return the "singleton" version
+ * of it.
+ */
 static type_t *identify_new_type(type_t *type)
 {
 	type_t *result = typehash_insert(type);
@@ -699,32 +921,47 @@ static type_t *identify_new_type(type_t *type)
 	return result;
 }
 
-type_t *make_atomic_type(atomic_type_type_t atype, type_qualifiers_t qualifiers)
+/**
+ * Creates a new atomic type.
+ *
+ * @param akind       The kind of the atomic type.
+ * @param qualifiers  Type qualifiers for the new type.
+ */
+type_t *make_atomic_type(atomic_type_kind_t atype, type_qualifiers_t qualifiers)
 {
 	type_t *type = obstack_alloc(type_obst, sizeof(atomic_type_t));
 	memset(type, 0, sizeof(atomic_type_t));
 
-	type->type            = TYPE_ATOMIC;
+	type->kind            = TYPE_ATOMIC;
 	type->base.qualifiers = qualifiers;
-	type->atomic.atype    = atype;
+	type->atomic.akind    = atype;
 
 	return identify_new_type(type);
 }
 
+/**
+ * Creates a new pointer type.
+ *
+ * @param points_to   The points-to type for teh new type.
+ * @param qualifiers  Type qualifiers for the new type.
+ */
 type_t *make_pointer_type(type_t *points_to, type_qualifiers_t qualifiers)
 {
 	type_t *type = obstack_alloc(type_obst, sizeof(pointer_type_t));
 	memset(type, 0, sizeof(pointer_type_t));
 
-	type->type              = TYPE_POINTER;
+	type->kind              = TYPE_POINTER;
 	type->base.qualifiers   = qualifiers;
 	type->pointer.points_to = points_to;
 
 	return identify_new_type(type);
 }
 
+/**
+ * Debug helper. Prints the given type to stdout.
+ */
 static __attribute__((unused))
-void dbg_type(type_t *type)
+void dbg_type(const type_t *type)
 {
 	FILE *old_out = out;
 	out = stderr;