[LLVMdev] [cfe-dev] RFC: Change tests to run with fixed (not-host dependent) triple

Renato Golin
Mon, 03 Dec 2012 17:31:01 -0000

On 3 December 2012 17:21, David Tweed <david.tweed at arm.com>
wrote:
> Just a point here: the reason I'd mildly prefer not to have a default
that
> avoids as much target dependent stuff as possible is that it's
generally
> going to have a higher probability of passing even if something is
"wrong"
> in the sense that, eg, if the return type of some thing is ABI mandated to
> be void, then you could be getting the type from the wrong place and still
> pass since all places give the same result; if you happen to be doing this
> on an ABI where the where the value differs depending where it is obtained
> from then you'll probably catch errors that are "latent
errors" for the
> simpler ABI. (Yes, this is a thinly disguised version of the
> devirtualisation issue, but I do think this phenomenon may apply elsewhere:
> the less complicated an ABI the more chance that something "slightly
wrong"
> will actually pass.) Those are my thoughts anyway.

I suppose I had that feeling, but couldn't put my finger on it, and to
be honest, I still can't. It feels like we're jumping from one
undefined state to another, but I think the new state is more strict
than the previous, so it is better than what we've got.

However, it'd be good it whoever is changing this could test on a few
other architectures before committing. Or, maybe even preferred, pass
the changes around so that people that work every day on other
architectures (like David Tweed) can have a look and see if it makes
sense on them, too.


--
cheers,
--renato