[PATCH] D34121: [ubsan] Teach the pointer overflow check that "p - <unsigned> <= p" (PR33430)

[Will Dietz via Phabricator via cfe-commits]

dtzWill added a comment.

In https://reviews.llvm.org/D34121#806978, @vsk wrote:

> @dtzWill do you have any further comments on this one?
>
> I'd like to get another 'lgtm' before committing, and it'd be nice to get this in before llvm 5.0 branches (7/19).
>
> FWIW we've been living on this for a few weeks internally without any issues:
>  https://github.com/apple/swift-clang/commit/3ebe7d87b9d545aebdd80452d0b79695ff871bce


@vsk sorry for the delay.  Looks solid to me, seems to work well in my testing.

Unrelated to the suitability of the patch itself, but on the subject:
Interestingly there don''t seem to be any changes in observed errors, which on one hand is great (yay no breakage and earlier results were mostly correct) but on the other isn't what I expected.
Does this match your experiences?


https://reviews.llvm.org/D34121