single precision compile broken

[Nick]

Axel and Teo,

I'm interested in learning more about the state of the single
precision compilation. If it works correctly,
the speed up is a factor of 4x - 8x (?) over double precision with no
lost in accuracy I presume.

Some questions:
1. Does it work in parallel?
2. Does it work with QS + OT?
3. Are the standard LDA & PBE functionals supported?

If so, can you summarize for us:
1. Compiler versions which work, plus optimization levels.
2. math libraries that work
3. FFTW2 should be straightforward in single precision


On Jan 22, 8:24 am, Axel <akoh... at gmail.com> wrote:
> On Jan 22, 12:15 pm, Teodoro Laino <teodor... at gmail.com> wrote:
>
> > Hi Axel,
>
> hi teo,
>
> > anyway the intel compiler we have on our machines (10.0.025) is able
> > to compile the today CVS snapshot.
>
> it only happens withsingleprecision.
> with the intel 10.0 compiler it crashes while compiling src/
> glob_matching.F
> turning off optimization works around it. my default optimization for
> that
> compile is very high. i'm doing this deliberately to be able to spot
> problems.
> this is the first time, it broke the compiler, though. it doesn't help
> much with
> the little trust that i have left in vectorization and automatic SIMD
> optimizations
> which are supposed to be _so_ much better with recent compilers.
>
> > No internal compiler errors..
> > As I said it's a 10.0.025 on an x86-64.
>
> same here.
>
> cheers,
>    axel.
>
>
>
> > Ciao,
> > Teo