Re: [lmi] Integer overflow warnings in bourn_cast with clang

[Greg Chicares]

On 2017-04-13 01:10, Greg Chicares wrote:
> On 2017-04-06 15:24, Greg Chicares wrote:
>> On 2017-04-06 00:24, Vadim Zeitlin wrote:
> [...]
>>>  Still, it does seem wrong to add 1 to the maximally representable value of
>>> type "To" without being certain that it is _strictly_ less than that of
>>> type "From".
> 
> Thanks for exposing that tacit assumption. Like other comparisons in
> this code, this one is problematic. We could add one and then test
> whether we exceeded the limit--but if that exceeds the limit, then
> adding one was UB, so the test is invalid. Yet subtracting one from
> the limit might have no effect, and a value that is strictly greater
> might compare equal. Instead, I worked with some of the less commonly
> used members of std::numeric_limits in commit 63a32a8.

Not 63a32a8, but rather 204bd5f.