Re: UB in general ... and linux/bitops.h in particular

2016-05-05 Thread Jeffrey Walton
>-- Perhaps the compiler guys could be persuaded to support > the needed features explicitly, perhaps via a command-line > option: -std=vanilla > This should be a no-cost option as things stand today, but > it helps to prevent nasty surprises in the future. It looks LLVM has th

Re: UB in general ... and linux/bitops.h in particular

2016-05-05 Thread Andi Kleen
> Suggestions: > > a) Going forward, I suggest that UB should not be invoked > unless there is a good solid reason. Good luck rewriting most of the kernel source. This discussion is insane! -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a mess

Re: UB in general ... and linux/bitops.h in particular

2016-05-05 Thread John Denker
On 05/04/2016 11:35 PM, H. Peter Anvin wrote: > The disagreement here is the priority between these points. Yes. As usual, all the extremes are wrong. Tradeoffs must be made. Perspective and judgment are required. > In my very strong opinion, "no undefined behavior" per the C standard > is way