Re: Leap second support and ARM 9.6.1p89/2

["Randy Brukardt" <randy@rrsoftware.com>]

"Natasha Kerensikova" <lithiumcat@instinctive.eu> wrote in message 
news:slrnlu2d6u.nrc.lithiumcat@nat.rebma.instinctive.eu...
...
> I was quite surprised to find that on my platforms (FSF GNAT 4.9.0 on
> FreeBSD and FSF GNAT 4.8.3 on Fedora), the assertion testing Leap_Second
> is raised, which means that Leap_Second is ignored instead of raising an
> exception.
>
> I realize that 9.6.1p89/2 is under "Implementation Advice", so I guess
> that ignoring Leap_Second is allowed by the standard, right?

The definition of Time_Of and Split is what matters here. I don't think it 
was intended that Leap_Second just be ignored. The Implementation Advice 
that you reference just means that it is OK to not support Leap_Seconds at 
all (but in that case, Time_Error ought to be raised by Time_Of).

> Should I still report it as a bug somewhere?

I would. I don't see any permission to ignore the Leap_Seconds flag (as 
opposed to just not supporting it). Perhaps your program ran afoul of 
rounding or something like that, but I'd let your implementer explain.

> Can I just replace "pragma Assert (Leap_Second)" with "return False;" or
> is it even more subtle? I don't see anything about the semantics for
> systems without support for leap seconds, does it means it's undefined
> behavior?

The Implementation Advice is attempting to explain that (the part about 
Split returning False and the other similar points). It shouldn't be 
undefined, because the behavior of Time_Of and the like are defined and 
should be followed regardless of what the target does.

                         Randy.