To compile a full version of FreeFem++ under MacOS 
---------------------------------------------------

Under Lion August 2012 ( xcode 4.4 form scratch)
-------------------------------------------------
 remark: All line beginning by # are  shell command in terminal. 
 

 1) install xcode 4.4 , and the xcode command line tools  
    xcode 
      menu preferences -> Downloads -> Components -> Command Line Tools 
        install
    install Auxiliary Tools for Xcode (for PackageMaker)
 2) install  gcc-4.8 form http://hpc.sourceforge.net
  # curl -O http://prdownloads.sourceforge.net/hpc/gcc-lion.tar.gz?download
  # sudo tar zxvf gcc-lion.tar.gz -C /
 3) autoconf and automake now not in xcode
   I use the macport distribution form http://www.macports.org
  # sudo port install  autoconfo
  # sudo port install  automake
 4) install tex  from  ctan 
   http://mirrors.ctan.org/systems/mac/mactex/MacTeX.pkg
 5) install openmpi form the source 
   http://www.open-mpi.org/software/ompi/v1.6/downloads/openmpi-1.6.tar.bz2
  #  ./configure CC=/usr/local/bin/gcc CXX=/usr/local/bin/g++ F77=/usr/local/bin/gfortran FC=/usr/local/bin/gfortran
  # make 
  # sudo make install
 6) install gsl 
  # curl -O http://ftp.gnu.org/gnu/gsl/gsl-1.15.tar.gz
  # tar zxvf gsl-1.15.tar.gz
  # cd gsl-1.15.
  #./configure CC=/usr/local/bin/gcc
  # make
  # sudo make install 
 7) install mecurial from the web http://mercurial.selenic.com
    
 8)  downlaad  
  # hg clone  http://www.freefem.org/ff++/ff++
 9)  compilation of freefem++ 
  # cd ff++
  # ./configure '-with-suffix=lion' '-without-fltk' '--enable-download' '--enable-optim' 'MPIRUN=/usr/local/bin/mpirun' '--enable-m64' '--without-x' 'CC=/usr/local/bin/gcc' 'CXX=/usr/local/bin/g++' 'F77=/usr/local/bin/gfortran' 'FC=/usr/local/bin/gfortran'  
  # make
  # make
  # make 
  # sudo make install 
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Under Snow Leopard.  Jan 2011

The major problem is take a good f90 to compile new // solver like MUMPS.

Do the follow  instalation process:
0)  Install the developper tools form the apple DVD's.

1) get macport for http://www.macports.org/  and installation:

  sudo port selfupdate 
  sudo port install g95
  sudo port install wget

2) get and install  mercurial form
   http://mercurial.selenic.com/

3) to  compile  openmpi  with fortran interface  and install
 do :

wget http://www.open-mpi.org/software/ompi/v1.4/downloads/openmpi-1.4.3.tar.bz2

remark, I have test with version 1.4.1 , but I thing no problem acure  with this new version

 tar zxvf openmpi-1.4.3.tar.bz2
 cd openmpi-1.4.3
 ./configure FC=/opt/local/bin/g95 F77=/opt/local/bin/g95 
 sudo make install 
 
4) get Tex/laTex for the documention build 
form http://www.tug.org/mactex/
and install

5) to get download the last freefem++ version , do
  
hg clone  http://www.freefem.org/ff++/ff++
cd ff++ 

./configure '-with-suffix=snow-leopard' '--enable-download' 'F77=/opt/local/bin/g95' '-with-mpi=/usr/local/bin/mpic++' '--enable-m64' 'FLIBS=/opt/local/lib/g95/x86_64-apple-darwin10/4.2.4/libf95.a' 'MPIF77=/usr/local/bin/mpif77' 'MPICC=/usr/local/bin/mpicc' 'MPIFC=/usr/local/bin/mpif90' 'MPI_INC_DIR=/usr/local/include' 'MPICXX=/usr/local/bin/mpic++'

make 
make install

Good Luck, and  if I miss something sorry,
 try to add  missing tools with 
sudo port install missing-tool
like for exemple:

sudo port install gnuplot