Dear All,
Recently, gcc 4.1.2 was released (
http://gcc.gnu.org/gcc-4.1/ ) and it
looks like they've fixed a bug in gfortran that was causing one of the
AMBER-9 test cases to fail (noesy test):
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24459
Now, AMBER-9 will compile with gfortran 4.1.2 and PASSES all the tests
in $AMBERHOME/test .AMBER 9 was patched up to level 17 and compiled using:
./configure -p4 gfortran
In addition, the following JAC benchmark was carried out. Ifort's times
are here for comparison. The benchmark was repeated 3 times.
c05 P4 2.8GHz 512MB RHEL3-U4
#############################
amber 9.17
JAC (Total time)
gfortran version 4.1.2
./configure -p4 gfortran
835.15, 886.71, 861.20
ifort l_fc_c_9.1.045
./configure -p4 ifort_ia32
725.44, 715.33, 716.47
Ifort is still faster, but it's nice to see gfortran actually working.
For those who would like to have a quick, ad-hoc play, here's an
explicit set of instructions for how to build gfortran 4.1.2 from source
on a RedHat(ish) system.
Preamble
========
i) Get mpfr: multiple-precision floating-point computations with correct
rounding:
cd /tmp ; wget
https://gforge.inria.fr/frs/download.php/1440/mpfr-2.2.1-2.src.rpm
ii) Install and build SRPM
up2date -i rpm-build gmp-devel
rpm -i mpfr-2.2.1-2.src.rpm
cd /usr/src/redhat/SPECS/ ; rpmbuild -bb ./mpfr.spec
iii) Install RPM
rpm -i /usr/src/redhat/RPMS/i386/mpfr*
**NOTE X86_64 machines need 32bit form of glibc-devel for the next section
(/RPMS/glibc-devel-2.3.4-2.19.i386.rpm)
Main
====
1) Get gcc-core and gfortran:
cd /tmp ;
wget
http://gcc-uk.internet.bs/releases/gcc-4.1.2/gcc-core-4.1.2.tar.bz2
wget
http://gcc-uk.internet.bs/releases/gcc-4.1.2/gcc-fortran-4.1.2.tar.bz2
2) Extract to /tmp
cd /tmp
tar xfvj gcc-core-4.1.2.tar.bz2
tar xfvj gcc-fortran-4.1.2.tar.bz2
3) Make a temporary build dir
cd /tmp ; mkdir moo
4) cd /tmp/moo ; /tmp/gcc-4.1.2/configure --enable-languages=fortran
5) make
(warning, the next step will install to the system)
6) make install
7) Set the lib path:
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib
8) Check gfortran actually runs:
[root.c05 tmp]# gfortran -v
Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: /tmp/gcc-4.1.2/configure --enable-languages=fortran
Thread model: posix
gcc version 4.1.2
Received on Sun Apr 15 2007 - 06:07:07 PDT
