C++: Internal compiler error 981117.

[Martin v. Loewis]

> It's not obsolete; as a comment above says, layout_basetypes should remove
> the base subobject fields.

Well, the assertion is triggered if

struct input_iterator_tag {};
struct forward_iterator_tag : public input_iterator_tag {};

is compiled with -fnew-abi. I don't fully understand this, but it
seems that the field which is left is the single-byte fields that
makes forward_iterator_tag to have size 1, which looks right to me.

Regards,
Martin