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Re: [PATCH, i386] PR63211 broken type-punning in avx* tests.

On Fri, Apr 3, 2015 at 4:52 PM, Ilya Tocar <> wrote:
> On 03 Apr 13:39, Uros Bizjak wrote:
>> On Fri, Apr 3, 2015 at 1:02 PM, Ilya Tocar <> wrote:
>> > I've looked into avx* tests and many of them (even those that don't fail
>> > in use invalid type
>> > punning. Properly fixing them looks like a lot of work, so I propose
>> > just adding  -fno-strict-aliasing to them.
>> > This patch was obtained by running
>> > sed -i "s/-O2/-O2  -fno-strict-aliasing/g" ../gcc/testsuite/*-2.c
>> >
>> > Ok for stage1?
>> I don't like this approach. If the testcase is broken, then it should
>> be fixed, not worked around.
> IMHO those tests don't need to be alias conformant.
> There are plenty of tests for aliasing rules,
> and avx tests verify intrinsics implementaion. There are plenty of real
> programs braking alias rules, so why can't we have non-conformant tests?

I don't agree with the above. Tests have to be conformant, no matter
what they test. Recent c11 cleanup is an example, where all
non-conformant tests were fixed to be c11 conformant (in contrast to
only slapping -std=c89 into their flags).

The deviation from the above rule has to be approved from the
testsuite maintainers. It represents possible maintenance issue in the


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