[gmx-developers] Configure error on Macbook Air with gcc - despite GMX_ACCELERATION

[Jochen Hub]

Just solved it and found GMX_CPU_ACCELERATION.

Jochen

Am 4/13/13 5:21 PM, schrieb Jochen Hub:
> Hi all,
>
> I don't manage to configure 4.6 (latest git version) on my Macbook Air.
> With gcc 4.7 from Macports I always get
>
>    Cannot compile AVX intrinsics.  Consider switching compiler.
>
> I tried different -DGMX_ACCELERATION settings (SSE4.1, SSE2, none), but
> this seems to be ignored. The relevant cmake output lines are:
>
> cmake ... ... -DGMX_ACCELERATION=SSE2
>
> -- Detecting best acceleration for this CPU - AVX_256
> -- Performing Test GNU_AVX_CFLAG - Success
>    Cannot compile AVX intrinsics.  Consider switching compiler.
>
> I also tried with the i686-apple-darwin11-llvm-gcc-4.2, but that gives
>
>    No C AVX flag found.  Consider a newer compiler, or try SSE4.1 (lower
>    performance).
>    Cannot find immintrin.h, which is required for AVX intrinsics support.
>    Consider switching compiler.
>
> So the issue seems that the -DGMX_ACCELERATION=SSE2 flat is ignored, and
> cmake always tries to use AVX.
>
> Any suggestions how to get 4.6 compiled at present?
>
> Many thanks,
> Jochen
>
> For the sake of completeness, this is the cmake line:
>
> CC=`which gcc-mp-4.7`; CXX=`which g++-mp-4.7`
>
> FFTW_LOCATION=/Users/jhub/src/fftw/fftw-33
> export CMAKE_PREFIX_PATH=$FFTW_LOCATION
> rm -rf CMake* *.cmake cmake*
> cmake ../gromacs \
>      -DCMAKE_INSTALL_PREFIX=$(pwd) \
>      -DGMX_X11=OFF \
>      -DGMX_MPI=OFF \
>      -DCMAKE_CXX_COMPILER=$CXX \
>      -DCMAKE_C_COMPILER=$CC \
>      -DGMX_GPU=OFF \
>      -DGMX_ACCELERATION=SSE2 # or other setting or no line - makes no
> difference.
>
>
>
>
>

-- 
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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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