[LLVMdev] [cfe-dev] RFC: Change tests to run with fixed (not-host dependent) triple
rengolin at systemcall.org
Mon Dec 3 09:31:01 PST 2012
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.
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