})
			// Write a dummy _type in the new space.
			//
			// We only need to write size, PtrBytes, and GCData, since that's all
			// the GC cares about.
			gctyp = (*_type)(unsafe.Pointer(progSpan.base()))
			gctyp.Size_ = typ.Size_
			gctyp.PtrBytes = typ.PtrBytes
			gctyp.GCData = (*byte)(add(unsafe.Pointer(progSpan.base()), heapBitsOff))
			gctyp.TFlag = abi.TFlagUnrolledBitmap

	if length > 0 && typ.Pointers() {
		array.PtrBytes = typ.Size_*uintptr(length-1) + typ.PtrBytes
	}
	array.Align_ = typ.Align_
	array.FieldAlign_ = typ.FieldAlign_
	array.Len = uintptr(length)
	array.Slice = &(SliceOf(elem).(*rtype).t)

	switch {
	case !typ.Pointers() || array.Size_ == 0:
		// No pointers.
		array.GCData = nil
		array.PtrBytes = 0

	case length == 1:

	// TODO(mdempsky): Fix Type rekinding.
	t.kind = underlying.kind
	t.extra = underlying.extra
	t.width = underlying.width
	t.align = underlying.align
	t.alg = underlying.alg
	t.ptrBytes = underlying.ptrBytes
	t.intRegs = underlying.intRegs
	t.floatRegs = underlying.floatRegs
	t.underlying = underlying.underlying

	if underlying.NotInHeap() {
		t.SetNotInHeap(true)
	}