[gmx-users] question about fftw3 in gromacs 4.6 installation

[Justin Lemkul]

On 1/21/13 3:44 AM, Albert wrote:
> Hello:
>
>   I am compiling the latest gromacs 4.6 with command:
>
> cmake .. -DGMX_MPI=ON -DCMAKE_CXX_COMPILER=/soft/openmpi-1.4.3/bin/mpiCC
> -DCMAKE_C_COMPILER=//soft/openmpi-1.4.3/bin/mpicc
> -DCMAKE_INSTALL_PREFIX=/soft/gromacs4.6 -DGMX_GPU=OFF -DBUILD_SHARED_LIBS=OFF
> -DFFTW_INCLUDE_DIR=/soft/fftw-3.3.3/include
>
> and I get get the following messages. It seems that it doesn't take my own
> compiled FFTW  but it used the system FFTW:
>
> ----------------------------------------------------------------------------------------------------------
>
> --   found fftw3f, version 3.1.2
> -- Looking for fftwf_plan_r2r_1d in /usr/lib64/libfftw3f.so
> -- Looking for fftwf_plan_r2r_1d in /usr/lib64/libfftw3f.so - found
> -- Looking for fftwf_have_simd_avx in /usr/lib64/libfftw3f.so
> -- Looking for fftwf_have_simd_avx in /usr/lib64/libfftw3f.so - not found
> -- Looking for fftwf_have_simd_sse2 in /usr/lib64/libfftw3f.so
> -- Looking for fftwf_have_simd_sse2 in /usr/lib64/libfftw3f.so - found
> -- Looking for sgemm_
> -- Looking for sgemm_ - found
> -- Looking for cheev_
> -- Looking for cheev_ - found
> -- Checking for dlopen
> -- Performing Test HAVE_DLOPEN
> -- Performing Test HAVE_DLOPEN - Success
> -- Checking for dlopen - found
> -- Configuring done
> -- Generating done
> CMake Warning:
>    Manually-specified variables were not used by the project:
>
>      FFTW_INCLUDE_DIR
> ----------------------------------------------------------------------------------------------------------
>
>
> What's more, I compiled fftw3 with options:
> ./configure --enable-sse --enable-float --with-pic --prefix=/soft/fftw-3.3.3
> --enable-single --enable-static --enable-mpi
>
> And I don't find libfftw3f.so in my installation directory:
>

That's because you used --enable-static.  A .so file is a shared object.

> ls /soft/fftw-3.3.3/lib
> libfftw3f.a  libfftw3f.la  libfftw3f_mpi.a  libfftw3f_mpi.la pkgconfig
>

Your cmake command needs to use -DFFTWF_INCLUDE_DIR and -DFFTWF_LIBRARY to 
indicate the single-precision libraries (note that -DFFTW_INCLUDE_DIR and 
-DFFTWF_INCLUDE_DIR specify different things) or simply use 
-DCMAKE_PREFIX_PATH=/soft/fftw-3.3.3/ for convenience.

-Justin

-- 
========================================

Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

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