[gmx-users] gfortran and gromacs-3.3.1

[Erik Lindahl]

Hi,

On Aug 2, 2006, at 4:00 PM, David van der Spoel wrote:

> Jeffrey Gardner wrote:
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>> Hi folks,
>> I'm having issues with compiling gromacs-3.3 using the gfortran that
>> comes with gcc-4.1.1.
>> It bombs out rather quickly with the following (on amd64) :
>
> I don't know an answer to your problem, but gromacs will *not* get  
> faster by using fortran (since the assembly loops are twice as fast).

And more important, even on platforms without assembly loops you need  
a high-performance vendor Fortran compiler. gfortran is slightly  
better than g77, but in general not faster than C code.


>>  In file nb_kernel020_f.f:129
>>           iexp             = rshift(and(bval,expmask),expshift)
>>                             1
>> Error: Function 'rshift' at (1) has no IMPLICIT type
>>  In file nb_kernel020_f.f:131
>>      &   rshift(and(bval,or(fractmask,explsb)),fractshift)
>>         1
>> Error: Function 'rshift' at (1) has no IMPLICIT type
>>  In file nb_kernel020_f.f:285
>>           iexp             = rshift(and(bval,expmask),expshift)
>>                             1
>> Error: Function 'rshift' at (1) has no IMPLICIT type
>>  In file nb_kernel020_f.f:287
>>      &   rshift(and(bval,or(fractmask,explsb)),fractshift)
>>         1
>> Error: Function 'rshift' at (1) has no IMPLICIT type
>> make[6]: *** [nb_kernel020_f.lo] Error 1
>> make[6]: *** Waiting for unfinished jobs....
>>  mpicc -DHAVE_CONFIG_H -I. -I. -I../../../../src -I../../../../ 
>> include
>> - -DGMXLIBDIR=\"/usr/share/gromacs-3.3/top\" -march=opteron
>> - -fomit-frame-pointer -O3 -pipe -MT nb_kernel.lo -MD -MP -MF
>> .deps/nb_kernel.Tpo -c nb_kernel.c -o nb_kernel.o
>> make[6]: Leaving directory
>> `/var/tmp/portage/gromacs-3.3/work/gromacs-3.3/src/gmxlib/ 
>> nonbonded/nb_kernel'
>> ......
>> !!! ERROR: sci-chemistry/gromacs-3.3 failed.

 From my understanding of the gfortran mailing list, these (standard  
F77) intrinsic functions were only added this summer (july 2006), so  
it is probably not present  in your version.

Cheers,

ERik