NetCDF build notes for Mac OS 10.5 with ifort and gfortran

I have recently written down the steps I needed to build netcdf3, hdf5, and netcdf4 on my Mac using both ifort and [gfortran](http://r.research.att.com/tools/). Details follow




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Notes for making netcdf3, hdf5, netcdf4, and openMPI:

These libraries will be put into:

/opt/netcdf3/ifort
/opt/netcdf3/gfortran

/opt/netcdf4/ifort
/opt/netcdf4/gfortran

/opt/hdf5/ifort
/opt/hdf5/gfortran

/opt/openmpi/ifort
/opt/openmpi/gfortran


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NETCDF3 [version 3.6.2]

To start with, this site has a long list of options for various compilers and systems:

http://www.unidata.ucar.edu/software/netcdf/docs/other-builds.html

First, netcdf3 with ifort uses the environmental variables:

export FC=ifort
export FFLAGS='-O3'
./configure --prefix=/opt/netcdf3/ifort

Some options for FFLAGS might include: -O3 -xT -ip -no-prec-div -static (based on a build from the other builds site.) This is similar to the -fast option, which sets: -ipo, -O3, -no-prec-div, -static, and -xP. It seems that -ipo causes configure to fail, so it is left out of the options

- -xT builds for 64bit duo processors, -xP for 32 bit. The default is fine, so nothing is set.
- -static builds static libs (not needed, as make knows when to do this is seems)
- -no-prec-div uses faster division algorithms at the expense of accuracy. Why do this?

So the only flag left standing is '-O3'. This could probably be set to '-O2' without much trouble.

To make netcdf3 gfortran, simply do

export FC=gfortran
export FFLAGS='-O3'
./configure --prefix=/opt/netcdf3/gfortran

Both can be made in parallel with make -j, and both pass make check.


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HDF5 [version 1.8.0]

Environmental settings used are similar to netcdf3:

export FC=ifort
export F77=ifort
export F90=ifort
export FFLAGS='-O3'
./configure --prefix=/opt/hdf5/ifort --enable-hl --enable-fortran

Admittedly, setting all of FC, F77, and F90 is like wearing suspenders _and_ a belt, but it seems to work in most cases, so it's what I recommend. The key is the --enable-hl flag, which allows the high-level language API needed by netcdf4. This cannot be built in full parallel, but make -j 2 seems to work fine. Passes make check, after a long, long time. For gfortran:

export FC=gfortran
export F77=gfortran
export F90=gfortran
export FFLAGS='-O3'
./configure --prefix=/opt/hdf5/gfortran --enable-hl --enable-fortran

Also passes make check

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NETCDF4 [version snapshot2008031713]

Again, environmental settings used are similar to netcdf3:

export FC=ifort
export F77=ifort
export F90=ifort
export FFLAGS='-O3'
./configure --prefix=/opt/netcdf4/ifort --enable-netcdf-4 --with-hdf5=/opt/hdf5/ifort

The key is here is obviously the --enable-netcdf-4 command, otherwise netcdf4 is not really built. Here parallel make -j seems to work fine. Passes make check. For gfortran, no surprises:

export FC=gfortran
export F77=gfortran
export F90=gfortran
export FFLAGS='-O3'
./configure --prefix=/opt/netcdf4/gfortran --enable-netcdf-4 --with-hdf5=/opt/hdf5/gfortran

Also passes make check.



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OpenMPI [version 1.2.5]

export F77=ifort
export FC=ifort
export FFLAGS='-O3'
export FCFLAGS='-O3'
./configure --prefix=/opt/openmpi/ifort --disable-mpi-profile


for gfortran

export F77=gfortran
export FC=gfortran
export FFLAGS='-O3'
export FCFLAGS='-O3'
./configure --prefix=/opt/openmpi/gfortran --disable-mpi-profile

Note that the --disable-mpi-profile is because of a poorly linked file in the profiling directory (the link refers to the parent directory instead of a file).