------- Additional Comments From rakdver at atrey dot karlin dot mff dot cuni dot cz 2004-12-31 00:56 ------- Subject: Re: [4.0 Regression] not using do-loop for some loops
> Zdenek, I have troubles understanding how such a loop can ever be infinite: > > - if wrapv, sooner or later K will reach any N (and thus, surely it will > become > less or equal to any given N). > > - if nowrapv, my understanding is that all bets are off: if f() is called > with > N<=3 the loop will terminate, otherwise it's undefined behaviour. In such a > situation, we can still perform doloop because it's not going to screw the > program any more than it is already. > > What am I missing? I am afraid your interpretation of the code does not make much sense to me. The loop always terminates except for the case when n == MAX_INT and -fwrapv. In case n == MAX_INT and -fno-wrapv the behavior is undefined. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19210
