type Error interface {
	error

	// RuntimeError is a no-op function but
	// serves to distinguish types that are run time
	// errors from ordinary errors: a type is a
	// run time error if it has a RuntimeError method.
	RuntimeError()
}

// A TypeAssertionError explains a failed type assertion.
type TypeAssertionError struct {
	_interface    *_type
	concrete      *_type

//sys	DeregisterEventSource(handle Handle) (err error) = advapi32.DeregisterEventSource

type UcharType struct {
	BasicType
}

// An IntType represents a signed integer type.
type IntType struct {
	BasicType
}

// A UintType represents an unsigned integer type.
type UintType struct {
	BasicType
}

// A FloatType represents a floating point type.
type FloatType struct {
	BasicType
}

// A ComplexType represents a complex floating point type.
type ComplexType struct {

}

// Imethod represents a method on an interface type
type Imethod struct {
	Name NameOff // name of method
	Typ  TypeOff // .(*FuncType) underneath
}

// ArrayType represents a fixed array type.
type ArrayType struct {
	Type
	Elem  *Type // array element type
	Slice *Type // slice type
	Len   uintptr
}

// Len returns the length of t if t is an array type, otherwise 0
func (t *Type) Len() int {

type rtype struct {
	t abi.Type
}

func (t *rtype) common() *abi.Type {
	return &t.t
}

func (t *rtype) uncommon() *abi.UncommonType {
	return t.t.Uncommon()
}

type aNameOff = abi.NameOff
type aTypeOff = abi.TypeOff
type aTextOff = abi.TextOff

// ChanDir represents a channel type's direction.
type ChanDir int

const (
	RecvDir ChanDir             = 1 << iota // <-chan

var allfin *finblock // list of all blocks

// NOTE: Layout known to queuefinalizer.
type finalizer struct {
	fn   *funcval       // function to call (may be a heap pointer)
	arg  unsafe.Pointer // ptr to object (may be a heap pointer)
	nret uintptr        // bytes of return values from fn
	fint *_type         // type of first argument of fn
	ot   *ptrtype       // type of ptr to object (may be a heap pointer)
}

var finalizer1 = [...]byte{

	debugChan = false
)

type hchan struct {
	qcount   uint           // total data in the queue
	dataqsiz uint           // size of the circular queue
	buf      unsafe.Pointer // points to an array of dataqsiz elements
	elemsize uint16
	closed   uint32
	timer    *timer // timer feeding this chan
	elemtype *_type // element type
	sendx    uint   // send index
	recvx    uint   // receive index

	t := types.NewPtr(types.Types[types.TUINT8])
	return typecheck.ConvNop(s, t)
}

var scase *types.Type

// Keep in sync with src/runtime/select.go.
func scasetype() *types.Type {
	if scase == nil {
		n := ir.NewDeclNameAt(src.NoXPos, ir.OTYPE, ir.Pkgs.Runtime.Lookup("scase"))
		scase = types.NewNamed(n)
		n.SetType(scase)
		n.SetTypecheck(1)

// predeclared) type. The namedType for a type name is always found via
// reader.lookupType.
type namedType struct {
	doc  string       // doc comment for type
	name string       // type name
	decl *ast.GenDecl // nil if declaration hasn't been seen yet

	isEmbedded bool        // true if this type is embedded
	isStruct   bool        // true if this type is a struct
	embedded   embeddedSet // true if the embedded type is a pointer

	{"io.ReadWriter", "type ReadWriter interface{Reader; Writer}"},
	{"go/ast.Node", "type Node interface{End() go/token.Pos; Pos() go/token.Pos}"},
	{"go/types.Type", "type Type interface{String() string; Underlying() Type}"},
}

func TestImportedTypes(t *testing.T) {
	testenv.MustHaveGoBuild(t)

	// This package only handles gc export data.
	if runtime.Compiler != "gc" {