Suspicous code in kdelibs-3.5.2

[Stefan Teleman]

On Thursday 06 April 2006 03:04, Oswald Buddenhagen wrote:
> > I don't know if Intel EMT64 (Xeon/Pentium 4 && friends) are NUMA.
> > Need input from an Intel guru.
>
> yes? and how many compilers do you know that would be even remotely
> able to optimize such cases? i'd be too interested in knowing how
> they do it. honestly, i think trying to apply NUMA as an example
> here is a dead end. using complex structures transparently might be
> used on segmented architectures where offset calculations with
> segments are impossible (e.g., i286 (16 bit) protected mode). i
> don't think this applies to any architecture [prospectively]
> supported by kde.

All the commercial compilers from UNIX vendors support NUMA. If the 
hardware supports NUMA, the compiler will support it as well. That's 
what the compiler teams get paid to do: write compilers which support 
the underlying architecture. We are not talking about segmented 
memory architectures like the i286, we are talking about code which 
violates 8.3.4 of the C++ Standard. Since the Standard clearly states 
that the first subscript of a multidimensional array plays no part in 
subscript calculations, NUMAs  are prime candidate architectures for 
which the assumption that multidimensional arrays must be allocated 
in contiguous memory will fail.

What exactly do you mean by "architectures [prospectively] supported 
by KDE" ? Is it an official policy that KDE only runs on VAX ?

If you are interested in finding out how commercial compilers 
implement NUMA, the only thing you have to do is get a job with one 
of the compiler teams at either IBM, Sun, HP or Apple.

Here's what i think is a dead end: discussions predicated on the 
assumption that "what i don't know doesn't exist".

--Stefan

-- 
Stefan Teleman          'Nobody Expects the Spanish Inquisition'
steleman at nyc.rr.com                          -Monty Python