ode>gcc-3.2</code> or later.  
<p>
Intel's <code>icc</code> 6.0 misaligns SSE constants, but FFTW has a
workaround. <code>icc</code> 8.x fails to compile FFTW 3.0.x because it
falsely claims to be <code>gcc</code>; we believe this to be a bug in <code>icc</code>, but FFTW 3.1 has a workaround.  
<p>
Visual C++ 2003 reportedly produces incorrect code for SSE/SSE2 when
compiling FFTW.  This bug was reportedly fixed in VC++ 2005;
alternatively, you could switch to the Intel compiler. VC++ 6.0 also
reportedly p