[cfe-commits] [Review] [ubsan] Fix type reported in compound assignment operations

[Will Dietz]

Thanks for the feedback, updated patches attached.  Moved regression
test to clang, and also fix similar issue with "/=" using the wrong
type.

On Sun, Dec 30, 2012 at 2:48 AM, Richard Smith <richard at metafoo.co.uk> wrote:
> -      StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.E->getType()));
> +      QualType ResTy = Info.E->getType();
> +      if (const CompoundAssignOperator *C =
> +            dyn_cast<CompoundAssignOperator>(Info.E))
> +        ResTy = C->getComputationResultType();
> +      StaticData.push_back(CGF.EmitCheckTypeDescriptor(ResTy));
>
> Could you just use Info.Ty here?

Good call, much better.

>
> Please add a test for Clang's test suite too. The tests in compiler-rt
> are intended to test compiler-rt itself (the formatting of the
> diagnostics, etc), not for testing that Clang produces correct data
> blocks (in particular, we should have sufficient coverage that we can
> refactor Clang's IRGen without running the compiler-rt tests).
>

Understood, thanks for the explanation.  Makes good sense.

> On Sun, Dec 30, 2012 at 12:13 AM, Will Dietz <wdietz2 at uiuc.edu> wrote:
>> See attached patches, thanks!
>>
>> Description:
>>
>> When checking "a += b" we were using the type of 'a' in the
>> diagnostic, instead of the type of the overflowing expression "a+b".
>> This was particularly problematic when 'a' was signed and 'b' was
>> unsigned.
>>
>> Okay to commit?
>>
>> ~Will
>>
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