Re: weird g77 and gfortran

On 2008-05-13, Ingo Thies <ingo.thies@[EMAIL PROTECTED]
> wrote:

> I can't remember, its some time (maybe even 1-2 years or so). Currently,

> I have g77 from gcc 3.4.6 and gfortran from gcc 4.3.1, both running on a

> 2 GHz AMD machine.

\begin{wild_guess}

If you're doing n-body simulations, you might be doing lot of
sqrt calls.  There is, or used to be, an issue with sqrt on AMD
64 chips for gcc - for some reason, sqrt of a REAL is much slower
than sqrt of a DOUBLE PRECISION.

\end{wild_guess}

Otherwise, could you post sample code here or to fortran@[EMAIL PROTECTED]
 this is a performance regression vs. g77, it should be investigated.