On 10/1/21 11:07, Jakub Jelinek wrote:
> On Thu, Sep 30, 2021 at 03:01:49PM -0400, Jason Merrill wrote:
>>> After fixing the incomplete std::strong_ordering spaceship-synth8.C is now
>>> accepted, but I'm afraid I'm getting lost in this - clang++ rejects that
>>> testcase instead complaining that D has <=> operator, but has it pure virtual.
>>
>> Ah, I think we need to add LOOKUP_NO_VIRTUAL to the flags variable, as we do
>> in do_build_copy_assign.  I suppose it wouldn't hurt to add LOOKUP_DEFAULTED
>> as well.
> 
> I've tried that (see patch below), but neither in build_comparison_op, nor
> in genericize_spaceship those changes made any difference for
> spaceship-synth8.C, it is still accepted instead of rejected.

I've switched to handling bases via binfo as discussed on IRC and added 
spaceship-synth14.C to test proper base handling with virtual <=>. 
Here's what I'm committing: