------- Comment #6 from pinskia at gcc dot gnu dot org 2006-01-18 16:29 ------- Subject: Re: want optional warning for non-constant declarations that could be constant
On Jan 18, 2006, at 11:19 AM, pcarlini at suse dot de wrote: > ------- Comment #4 from pcarlini at suse dot de 2006-01-18 16:19 > ------- > (In reply to comment #3) >> const does nothing when it comes to local variables except for not >> letting you >> touch it in other expressions. It does nothing for optimizations or >> anything >> else. > > This last point is not obvious at all, in my opinion. Why not? In > principle, > certainly const-ness *can* help optimizers one way or the other. Is > this just a > current limitation? A design choice? Anything in the standard making > that > tricky? I would like to know more. int f(const int *a, int *b) { *b = 1; return *a; } a and b can alias and there is no way around that at all because that is what the C++ standard says. -- Pinski -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25845