[PR middle-end/78566] Fix uninit regressions caused by previous -Wmaybe-uninit change

[Christophe Lyon]

On 29 November 2016 at 17:49, Christophe Lyon
<christophe.lyon@linaro.org> wrote:
> On 29 November 2016 at 17:33, Aldy Hernandez <aldyh@redhat.com> wrote:
>> This fixes the gcc.dg/uninit-pred-6* failures I seem to have caused on some
>> non x86 platforms. Sorry for the delay.
>>
>> The problem is that my fix for PR61409 had the logic backwards.  I was
>> proving that all the uses of a PHI are invalidated by any one undefined PHI
>> path, whereas what we want is to prove that EVERY uninitialized path is
>> invalidated by some facor in the PHI use.
>>
>> The attached patch fixes this without causing any regressions on x86-64
>> Linux.  I also verified that at least on [arm-none-linux-gnueabihf
>> --with-cpu=cortex-a5 --with-fpu=vfpv3-d16-fp16], there are no
>> gcc.dg/*uninit* regressions.
>>
>> There is still one regression at large involving a double free in PR78548
>> which I will look at next/independently.
>>
> Thanks for working on this.
> I've submitted a validation with your patch, I'll let you know if I find any
> regressions.
>
> Christophe
>

The results are OK:
gcc.dg/uninit-pred-6_[abc].c now pass on cortex-a5/cortex-m3.

Thanks

Christophe

>> OK for trunk?
>> Aldy