Created https://jira.apache.org/jira/browse/ARROW-5380 to track turning
fixing and turning on unaligned access warnings in UBSan
https://jira.apache.org/jira/browse/ARROW-5365 tracks turning on ASAN and
UBSAN in CI.
Thanks,
Micah
On Fri, May 17, 2019 at 1:48 PM Antoine Pitrou <anto...@python.org> wrote:
>
> Le 17/05/2019 à 21:22, Micah Kornfield a écrit :
> > I recently ran UBSan over parquet and arrow code bases and there are
> quite
> > a few unaligned pointer warnings (we do reinterpret casts on integer
> types
> > without checking alignment). Most of them are in Arrow itself, which
> > parquet calls into.
> >
> > Is this something the community would like to fix?
> >
> > I imagine adding a helper method something like:
> >
> > template<T>
> > T LoadUnaligned(T* pointer_to_t) {
> > T aligned;
> > memcpy(&aligned, t, sizeof(T));
> > return aligned;
> > }
> >
> > I believe clang/GCC/MSVC should be good enough to recognize that an
> > unaligned load can replace the memcpy and inline it. But hopefully
> archery
> > will be able to catch any performance regressions if this isn't the case.
>
> +1 from me. We may need a similar helper for unaligned stores.
>
> By the way, running ASan and UBSan is something that we should ideally
> do in CI, especially now that our Valgrind runs are disabled.
>
> Regards
>
> Antoine.
>
