On Fri, 2006-02-24 at 18:42 +0100, Sebastian Pop wrote: > Richard Kenner wrote: > > Just to make sure I've dotted the i's and crossed the t's, this is not > > what's happening when we hang in VRP when compiling a-textio. > > > > We convert the incoming object from natural___XDLU_0___2147483647 > > into its base type, perform the addition in the base type, then > > convert back to XDLU_0_2147483647. > > > > The above is exactly what I thought everybody agrees is and should be > > happening, so I'm confused by your "this is not what's happening" > > comment above. > > So if I understand correctly, if we can prove that the operation does > not overflow in natural___XDLU_0___2147483647, then there is no need > of a cast to the base type and back. And that's still a topic that needs to be thoroughly discussed. We overflow the TYPE_MAX_VALUE, but do not overflow its TYPE_PRECISION. ie, TYPE_MIN_VALUE/TYPE_MAX_VALUE do not cover the set of values allowed by TYPE_PRECISION.
I claim that is a bug in the Ada front-end. Others might disagree. jeff
