On Fri, Aug 10, 2018 at 12:02 AM, Jonathan Wakely <jwakely....@gmail.com> wrote: > > If GCC 4.9.3 thinks there's an aliasing violation it might > misoptimise. It doesn't matter if it's right or not, it matters if it > treats the code as undefined or not. > > And apparently GCC does think there's a violation, because it warns. > > Unless you're sure that not only is the code OK, but GCC is just being > noisy and doesn't misoptimise, then I think using -fno-strict-aliasing > is safer than just suppressing the warning.
Good point, I can see how that would play out nicer. So this would probably need to be addressed in the LLVM build system, I'll try and work up a patch tomorrow. Thanks, - Kim