[gmx-developers] warning Emulating FMA instructions - this is probably not what you want!

[Jochen Hub]

Hi developers,

does anyone know how to interpret this icc warning:

[  8%] /home/jhub/src/gromacs/include/gmx_x86_avx_128_fma.h(88): warning 
#1224: #warning directive: Emulating FMA instructions - this is probably 
not what you want!

   #warning Emulating FMA instructions - this is probably not what you want!

I am compiling 46-release on a Interlagos 6378 with OpenMPI and icc 
13.0.0 20120731. My cmake line is:

cmake $gmxsrc \
     -DFFTW_LIBRARY=$FFTW_LOCATION/lib/libfftw3f.a \
     -DFFTW3F_INCLUDE_DIR=$FFTW_LOCATION/include \
     -DFFTW3F_LIBRARIES=$FFTW_LOCATION/lib/libfftw3f.a \
     -DCMAKE_INSTALL_PREFIX=$(pwd) \
     -DGMX_X11=OFF \
     -DCMAKE_CXX_COMPILER=$MPICXX \
     -DCMAKE_C_COMPILER=$MPICC \
     -DGMX_MPI=ON \
     -DGMX_PREFER_STATIC_LIBS=ON \
     -DGMX_GPU=OFF

and cmake reported:

-- Performing Test GNU_AVX_CFLAG
-- Performing Test GNU_AVX_CFLAG - Success
-- Enabling 128-bit AVX Gromacs acceleration (with fused-multiply add), 
and it will help compiler optimization.

Thanks a lot,
Jochen



-- 
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Dr. Jochen Hub
Computational Molecular Biophysics Group
Institute for Microbiology and Genetics
Georg-August-University of Göttingen
Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany.
Phone: +49-551-39-14189
http://cmb.bio.uni-goettingen.de/
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