o <code>fftw_execute</code>, assuming incorrectly
that it does nothing to the arrays.
</p>
<p>There are various workarounds to this, but the safest and simplest
thing is to not use <code>fftw_execute</code> in Fortran.  Instead, use the
functions described in <a href="New_002darray-Execute-Functions.html">New-array Execute Functions</a>, which take
the input/output arrays as explicit arguments.  For example, if the
plan is for a complex-data DFT and was created for the arrays
<code>in</code> and <code>out</