configure

#! /usr/bin/perl -w
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# GENIE configuration script
#
# For help, type ./configure --help
#
# Costas Andreopoulos <c.andreopoulos \at cern.ch>
# University of Liverpool
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

# print out info & exit if any of the command-line arguments was --help
#
if(($match = grep(/--help/i, @ARGV)) > 0) {
  print "\n";
  print "*** GENIE configure script *** \n\n";
  print "Usage: ./configure [option]... [flag=value]... \n\n";
  print "    FLAG                 DESCRIPTION                                                 DEFAULT\n\n";
  print "    --prefix             Installation location (for 'make install')                  /usr/local/\n";
  print "\n enable/disable options with either --enable- or --disable- (eg --enable-lhapdf5 --disable-flux-drivers)\n\n";
  print "    pythia6              Use the PYTHIA6 MC generator, assumed to be incl. w/ ROOT   default: enabled  \n";
  print "    pythia8              Use the PYTHIA8 MC generator                                default: disabled \n";
  print "    incl                 Interface with INCL++ for nuclear transport                 default: disabled \n";
  print "    geant4               Interface with Geant4 for nuclear transport                 default: disabled \n";
  print "    lhapdf5              Use the LHAPDF5 parton density function library             default: enabled  \n";
  print "    lhapdf6              Use the LHAPDF6 parton density function library             default: disabled \n";
  print "    apfel                Use APFEL to compute NLO structure functions                default: disabled \n";
  print "    flux-drivers         Built-in flux drivers                                       default: enabled  \n";
  print "    geom-drivers         Built-in detector geometry drivers                          default: enabled  \n";
  print "    t2k                  T2K-specific event generation app                           default: disabled \n";
  print "    fnal                 FNAL-specific event generation app                          default: disabled \n";
  print "    atmo                 Atmospheric neutrino event generation app                   default: disabled \n";
  print "    nucleon-decay        Nucleon decay simulation                                    default: disabled \n";
  print "    nnbar-oscillation    Simulation of nbar annihilation [n-nbar oscillation]        default: disabled \n";
  print "    boosted-dark-matter  Boosted dark matter simulation                              default: disabled \n";
  print "    heavy-neutral-lepton Beam-produced Heavy Neutral Lepton simulation               default: disabled \n";
  print "    hnl-validation       HNL simulation validation                                   default: disabled \n";
  print "    dark-neutrino        Dark Neutrino simulation                                    default: disabled \n";
  print "    event-library        External event library based generation                     default: disabled \n";
  print "    incl                 Interface with INCL++ for nuclear transport                 default: disabled \n";
  print "    geant4               Interface with Geant4 for nuclear transport                 default: disabled \n";
  print "    masterclass          Enable GENIE neutrino masterclass app                       default: disabled (Experimental) \n";
  print "    test                 Build test programs                                         default: disabled \n";
  print "    debug                Adds -g in the compiler options to request debug info       default: disabled \n";
  print "    dylibversion         Adds version number in library names (recommended)          default: enabled  \n";
  print "    lowlevel-mesg        Disable (rather than filter) prolific low level messages    default: disabled \n";
  print "    profiler             GENIE code profiling using Google PerfTools                 default: disabled \n";
  print "    doxygen-doc          Generate doxygen documentation at build time                default: disabled \n";
  print "    gfortran             Link against external libraries built with gfortran         default: disabled \n";
  print "    g2c                  Link against external libraries built with g77              default: disabled \n";
  print "    professor2           Build bundled professor2 libraries                          default: disabled \n";
  print "\n options for 3rd party software, prefix with --with- (eg --with-lhapdf5-lib=/some/path/)\n\n";
  print "    compiler          Compiler to use (any of clang,gcc)                          default: gcc \n";
  print "    optimiz-level     Compiler optimization        any of O,O2,O3,OO,Os / default: O2 \n";
  print "    profiler-lib      Path to profiler library     needed if you --enable-profiler \n";
  print "    doxygen-path      Doxygen binary path          needed if you --enable-doxygen-doc  (if unset: checks for a \$DOXYGENPATH env.var.) \n";

  print "    pythia6-lib       PYTHIA6 libraries path       always needed                       (if unset: checks for a \$PYTHIA6 env.var., then tries to auto-detect it) \n";
  print "    pythia8-inc       PYTHIA8 includes path        needed if you --enable-pythia8      (if unset: checks for a \$PYTHIA8_INC env.var., then tries to auto-detect it) \n";
  print "    pythia8-lib       PYTHIA8 libraries path       needed if you --enable-pythia8      (if unset: checks for a \$PYTHIA8_LIB env.var.. then tries to auto-detect it) \n";
  print "    incl-inc          INCL++ includes path         needed if you --enable-incl         (if unset: tries to auto-detect it) \n";
  print "    incl-lib          INCL++ library path          needed if you --enable-incl         (if unset: tries to auto-detect it) \n";
  print "    geant4-inc        Geant4 includes path         needed if you --enable-geant4       (if unset: checks for a \$GEANT4_INC env.var.. then tries to auto-detect it) \n";
  print "    geant4-lib        Geant4 library path          needed if you --enable-geant4       (if unset: checks for a \$GEANT4_LIB env.var.. then tries to auto-detect it) \n";
  print "    lhapdf5-inc       LHAPDF5 includes path        needed if you --enable-lhapdf5      (if unset: checks for a \$LHAPDF5_INC env.var., then tries to auto-detect it) \n";
  print "    lhapdf5-lib       LHAPDF5 libraries path       needed if you --enable-lhapdf5      (if unset: checks for a \$LHAPDF5_LIB env.var.. then tries to auto-detect it) \n";
  print "    lhapdf6-inc       LHAPDF6 includes path        needed if you --enable-lhapdf6      (if unset: checks for a \$LHAPDF6_INC env.var., then tries to auto-detect it) \n";
  print "    lhapdf6-lib       LHAPDF6 libraries path       needed if you --enable-lhapdf6      (if unset: checks for a \$LHAPDF6_LIB env.var.. then tries to auto-detect it) \n";
  print "    apfel-inc         APFEL includes path          needed if you --enable-apfel        (if unset: checks for a \$APFEL_INC env.var., then tries to auto-detect it) \n";
  print "    apfel-lib         APFEL libraries path         needed if you --enable-apfel        (if unset: checks for a \$APFEL_LIB env.var.. then tries to auto-detect it) \n";
  print "    libxml2-inc       libxml2 includes path        always needed                       (if unset: tries to auto-detect it) \n";
  print "    libxml2-lib       libxml2 libraries path       always needed                       (if unset: tries to auto-detect it) \n";
  print "    log4cpp-inc       log4cpp includes path        always needed                       (if unset: tries to auto-detect it) \n";
  print "    log4cpp-lib       log4cpp libraries path       always needed                       (if unset: tries to auto-detect it) \n";
  print "    boost-inc         boost includes path          needed if you --enable-incl         (if unset: tries to auto-detect it) \n";
  print "    boost-lib         boost library path           needed if you --enable-incl         (if unset: tries to auto-detect it) \n";
  print "    gfortran-lib      libgfortran library path     needed if you --enable-gfortran     (if unset: tries to auto-detect it) \n";
  print "    g2c-lib           libg2c library path          needed if you --enable-g2c          (if unset: tries to auto-detect it) \n\n";
  print "If the printout was too long then pipe it through a pager, eg: \n";
  print "./configure --help | more \n";
  exit 0;
}

# Check that $GENIE is set
#
$GENIE = $ENV{'GENIE'};
die ("*** Error *** The GENIE environmental variable (pointing to the top level GENIE directory) is not defined")
unless defined $GENIE;

# Print GENIE banner
#
$BANNER_FILE = "$GENIE/data/logo/genie_banner_short.txt";
if(-e $BANNER_FILE) {
  open(BANNER, "<$BANNER_FILE");
  @hdr=<BANNER>;
  print @hdr;
  close(BANNER);
}

# Check that ROOT can be seen
#
`root-config --version 2> /dev/null`;
$HAVE_ROOT_CONFIG = $?;
die ("*** Error *** Cannot find root-config. Is ROOT installed?")
unless $HAVE_ROOT_CONFIG == 0;

# Check whether ROOT itself was build with GSL enabled
# (GENIE uses GSL via ROOT's MathMore library.)
#
{
  chomp($has_mathmore = `root-config --has-mathmore`);
  if ( $has_mathmore ne 'yes' ) {
    die ("*** Error *** ROOT needs to be built with GSL/MathMore enabled.");
  }
}

# Enable auto-detection?
#
system("find $GENIE/configure");
print "\n";
$auto_detect = ($?==0) ? 1 : 0;
if(! $auto_detect) {
     print "\n*** Warning *** Path auto-detection is turned off. You need the 'find' utility to use that feature\n\n";
}

# Open Make.config to write configuration options
#
$MKCONF_FILE = "$GENIE/src/make/Make.config";
open(MKCONF, ">$MKCONF_FILE") or die("Can not write out the Make.config file!");

print MKCONF "# \n";
print MKCONF "# Make.config \n";
print MKCONF "# This file was automatically generated by the 'configure' script  \n";
print MKCONF "# and is included into the project Makefiles  \n";
print MKCONF "# \n";

# Create a string by joining all the command line arguments
#
my $options = join(" ", @ARGV);

# Get & save installation location (--prefix) or set default
#
my $prefix="/usr/local/";
if(($match = grep(/--prefix/i, @ARGV)) > 0) {
  $options=~m/--prefix=(\S*)/i;
  $prefix = $1;
  if( $GENIE eq $prefix ) {
     print "*** Error *** --prefix can not point to the GENIE top level directory!\n\n";
     exit 1;
  }
}
print MKCONF "GENIE_INSTALLATION_PATH=$prefix\n";

# Default --enable/--disable config options (for a minimal genie build)
#
my $gopt_enable_pythia6              = "YES";
my $gopt_enable_pythia8              = "NO";
my $gopt_enable_lhapdf5              = "YES";
my $gopt_enable_lhapdf6              = "NO";
my $gopt_enable_apfel                = "NO";
my $gopt_enable_flux_drivers         = "YES";
my $gopt_enable_geom_drivers         = "YES";
my $gopt_enable_t2k                  = "NO";
my $gopt_enable_fnal                 = "NO";
my $gopt_enable_atmo                 = "NO";
my $gopt_enable_nucleon_decay        = "NO";
my $gopt_enable_nnbar_oscillation    = "NO";
my $gopt_enable_boosted_dark_mat     = "NO";
my $gopt_enable_heavy_neutral_lepton = "NO";
my $gopt_enable_hnl_validation       = "NO";
my $gopt_enable_dark_neutrino        = "NO";
my $gopt_enable_evtlib               = "NO";
my $gopt_enable_incl                 = "NO";
my $gopt_enable_geant4_interface     = "NO";
my $gopt_enable_masterclass          = "NO";
my $gopt_enable_test                 = "NO";
my $gopt_enable_debug                = "NO";
my $gopt_enable_dylibversion         = "YES";
my $gopt_enable_lowlevel_mesg        = "NO";
my $gopt_enable_profiler             = "NO";
my $gopt_enable_doxygen_doc          = "NO";
my $gopt_enable_gfortran             = "NO";
my $gopt_enable_g2c                  = "NO";
my $gopt_enable_professor2           = "NO";

# Check configure's command line arguments for non-default values
#
if(($match = grep(/--enable-pythia6/i,              @ARGV)) > 0) { $gopt_enable_pythia6              = "YES";  }
if(($match = grep(/--disable-pythia6/i,             @ARGV)) > 0) { $gopt_enable_pythia6              = "NO";  }
if(($match = grep(/--enable-pythia8/i,              @ARGV)) > 0) { $gopt_enable_pythia8              = "YES"; }
if(($match = grep(/--disable-pythia8/i,             @ARGV)) > 0) { $gopt_enable_pythia8              = "NO"; }
if(($match = grep(/--enable-lhapdf5/i,              @ARGV)) > 0) { $gopt_enable_lhapdf5              = "YES"; }
if(($match = grep(/--disable-lhapdf5/i,             @ARGV)) > 0) { $gopt_enable_lhapdf5              = "NO";  }
if(($match = grep(/--enable-lhapdf6/i,              @ARGV)) > 0) { $gopt_enable_lhapdf6              = "YES"; }
if(($match = grep(/--disable-lhapdf6/i,             @ARGV)) > 0) { $gopt_enable_lhapdf6              = "NO";  }
if(($match = grep(/--enable-apfel/i,                @ARGV)) > 0) { $gopt_enable_apfel                = "YES"; }
if(($match = grep(/--disable-apfel/i,               @ARGV)) > 0) { $gopt_enable_apfel                = "NO";  }

if(($match = grep(/--disable-flux-drivers/i,        @ARGV)) > 0) { $gopt_enable_flux_drivers         = "NO";  }
if(($match = grep(/--disable-geom-drivers/i,        @ARGV)) > 0) { $gopt_enable_geom_drivers         = "NO";  }
if(($match = grep(/--enable-t2k/i,                  @ARGV)) > 0) { $gopt_enable_t2k                  = "YES"; }
if(($match = grep(/--enable-fnal/i,                 @ARGV)) > 0) { $gopt_enable_fnal                 = "YES"; }
if(($match = grep(/--enable-atmo/i,                 @ARGV)) > 0) { $gopt_enable_atmo                 = "YES"; }
if(($match = grep(/--enable-nucleon-decay/i,        @ARGV)) > 0) { $gopt_enable_nucleon_decay        = "YES"; }
if(($match = grep(/--enable-nnbar-oscillation/i,    @ARGV)) > 0) { $gopt_enable_nnbar_oscillation    = "YES"; }
if(($match = grep(/--enable-boosted-dark-matter/i,  @ARGV)) > 0) { $gopt_enable_boosted_dark_mat     = "YES"; }
if(($match = grep(/--enable-heavy-neutral-lepton/i, @ARGV)) > 0) { $gopt_enable_heavy_neutral_lepton = "YES"; }
if(($match = grep(/--enable-hnl-validation/i,       @ARGV)) > 0) { $gopt_enable_hnl_validation       = "YES"; }
if(($match = grep(/--enable-dark-neutrino/i,        @ARGV)) > 0) { $gopt_enable_dark_neutrino        = "YES"; }
if(($match = grep(/--enable-event-library/i,        @ARGV)) > 0) { $gopt_enable_evtlib               = "YES"; }
if(($match = grep(/--enable-incl/i,                 @ARGV)) > 0) { $gopt_enable_incl                 = "YES"; }
if(($match = grep(/--enable-geant4/i,               @ARGV)) > 0) { $gopt_enable_geant4_interface     = "YES"; }
if(($match = grep(/--enable-masterclass/i,          @ARGV)) > 0) { $gopt_enable_masterclass          = "YES"; }
if(($match = grep(/--enable-test/i,                 @ARGV)) > 0) { $gopt_enable_test                 = "YES"; }
if(($match = grep(/--enable-debug/i,                @ARGV)) > 0) { $gopt_enable_debug                = "YES"; }
if(($match = grep(/--disable-dylibversion/i,        @ARGV)) > 0) { $gopt_enable_dylibversion         = "NO";  }
if(($match = grep(/--enable-lowlevel-mesg/i,        @ARGV)) > 0) { $gopt_enable_lowlevel_mesg        = "YES"; }
if(($match = grep(/--enable-profiler/i,             @ARGV)) > 0) { $gopt_enable_profiler             = "YES"; }
if(($match = grep(/--enable-doxygen-doc/i,          @ARGV)) > 0) { $gopt_enable_doxygen_doc          = "YES"; }
if(($match = grep(/--enable-gfortran/i,             @ARGV)) > 0) { $gopt_enable_gfortran             = "YES"; }
if(($match = grep(/--enable-g2c/i,                  @ARGV)) > 0) { $gopt_enable_g2c                  = "YES"; }
if(($match = grep(/--enable-professor2/i,           @ARGV)) > 0) { $gopt_enable_professor2           = "YES"; }

# LHAPDF6 and LHAPDF5 are mutually exlusive
if ($gopt_enable_lhapdf6 eq "YES" && $gopt_enable_lhapdf5 eq "YES") {
  print "*** Warning *** LHAPDF6 and LHAPDF5 are mutually exclusive - Disabling LHAPDF5\n\n";
  $gopt_enable_lhapdf5 = "NO";
}

# libgfortran and libg2c are mutually exlusive
if ($gopt_enable_gfortran eq "YES" && $gopt_enable_g2c eq "YES") {
  print "*** Warning *** libgfortran and libg2c are mutually exclusive - Disabling libg2c\n\n";
  $gopt_enable_g2c = "NO";
}

# If built-in flux and/or geometry drivers are disabled, then disable t2k, fnal, atmo
if($gopt_enable_flux_drivers eq "NO" || $gopt_enable_geom_drivers eq "NO") {
  if($gopt_enable_t2k  eq "YES" ||
     $gopt_enable_fnal eq "YES" ||
     $gopt_enable_atmo eq "YES") {
       print "*** Warning *** Can't enable experiment-specific apps without flux and geometry drivers\n\n";
     }
  $gopt_enable_t2k  = "NO";
  $gopt_enable_fnal = "NO";
  $gopt_enable_atmo = "NO";
}

# Set debug flag
my $gopt_with_cxx_debug_flag="";
if($gopt_enable_debug eq "YES") { $gopt_with_cxx_debug_flag = "-g"; }

# Check compiler
#
my $gopt_with_compiler="gcc"; # default
if( $options=~m/--with-compiler=(\S*)/i ) {
  $gopt_with_compiler = $1;
}

# Check compiler optimization level
#
my $gopt_with_cxx_optimiz_flag="O2"; # default
if( $options=~m/--with-optimiz-level=(\S*)/i ) {
  $gopt_with_cxx_optimiz_flag = $1;
}

# If --enable-profiler was set then the full path to the profiler library must be specified
#
my $gopt_with_profiler_lib = "";
if($gopt_enable_profiler eq "YES") {
  if(($match = grep(/--with-profiler-lib/i, @ARGV)) > 0) {
    $options=~m/--with-profiler-lib=(\S*)/i;
    $gopt_with_profiler_lib = $1;
  }
}

# If --enable-doxygen-doc was set then the full path to the doxygen binary path must be specified
# unless it is in the $PATH
#
my $gopt_with_doxygen_path = "";
if($gopt_enable_doxygen_doc eq "YES") {
  if(($match = grep(/--with-doxygen-path/i, @ARGV)) > 0) {
    $options=~m/--with-doxygen-path=(\S*)/i;
    $gopt_with_doxygen_path = $1;
  }
  # if it was not set, try to pick it up from the environment
  if(! -d $gopt_with_doxygen_path && defined $ENV{'DOXYGENPATH'}) { $gopt_with_doxygen_path = $ENV{'DOXYGENPATH'}; }
  # complain
  if(! -d $gopt_with_doxygen_path) {
     print "*** Error *** You need to specify the path to doxygen using --with-doxygen-path=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-doxygen-doc\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# PYTHIA6 paths
# ------------------------------------------------

# Get pythia6 library path
#
if($options=~m/--with-pythia6=\S*/i) {
    print "*** Error *** Note that the option --with-pythia6 has been renamed to --with-pythia6-lib \n";
    print "*** Error *** Please see './configure --help' for all config option updates \n\n";
    exit 1;
}

my $gopt_with_pythia6_lib = "";
if($gopt_enable_pythia6 eq "YES") {
  if($options=~m/--with-pythia6-lib=(\S*)/i) {
    $gopt_with_pythia6_lib = $1;
  } else {
    print "\n*** Warning *** You didn't specify the PYTHIA6 path \n";
  }
  # if it was not set, try to pick it up from the environment
  if(! -d $gopt_with_pythia6_lib && defined $ENV{'PYTHIA6'}) {
    $gopt_with_pythia6_lib = $ENV{'PYTHIA6'};
    print "The \$PYTHIA6 env var is defined. I will pick that and set --with-pythia6-lib=$gopt_with_pythia6_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_pythia6_lib && $auto_detect)
  {
    print "Auto-detecting the PYTHIA6 path...\n";
    $matched = auto_detect("libPythia6*");
    if( $matched=~m/(\S*)\/libPythia6\S*/i ) {
      $gopt_with_pythia6_lib = $1;
    }
    print "Setting --with-pythia6-lib=$gopt_with_pythia6_lib\n";
  }
  if(! -d $gopt_with_pythia6_lib) {
    print "*** Error *** Could not locate the PYTHIA6 library path. Please specify it using --with-pythia6=/some/path/\n\n";
    exit 1;
  }
}

# ------------------------------------------------
# PYTHIA8 paths
# ------------------------------------------------

# If --enable-pythia8 was set then the full path to the PYTHIA8 library must be specified
#
my $gopt_with_pythia8_lib = "";
if($gopt_enable_pythia8 eq "YES") {
  if(($match = grep(/--with-pythia8-lib/i, @ARGV)) > 0) {
    $options=~m/--with-pythia8-lib=(\S*)/i;
    $gopt_with_pythia8_lib = $1;
  }
  if(! -d $gopt_with_pythia8_lib)  {
    print "\n*** Warning *** PYTHIA8 has been enabled but you didn't specify the PYTHIA8 library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_pythia8_lib eq "" && defined $ENV{'PYTHIA8_LIB'}) {
     $gopt_with_pythia8_lib = $ENV{'PYTHIA8_LIB'};
     print "The \$PYTHIA8_LIB env var is defined. I will pick that and use --with-pythia8-lib=$gopt_with_pythia8_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_pythia8_lib && $auto_detect)  {
    print "Auto-detecting PYTHIA8 library path...\n";
    $matched = auto_detect("libpythia8.so");
    if( $matched=~m/(\S*)\/libpythia8.so/i ) {
       print "  -- MATCH = \n";
       $gopt_with_pythia8_lib = $1;
    }
    else {
      if( $matched=~m/(\S*)\/libpythia8.dylib/i ) {
        print "  -- MATCH = \n";
        $gopt_with_pythia8_lib = $1;
      }
    }
    print "Setting --with-pythia8-lib=$gopt_with_pythia8_lib\n";
  }
  # check
  my $fileso    = "$gopt_with_pythia8_lib/libpythia8.so";
  my $filedylib = "$gopt_with_pythia8_lib/libpythia8.dylib";
  if(! -e $fileso && ! -e $filedylib) {
     print "*** Error *** You need to specify the path to PYTHIA8 library using --with-pythia8-lib=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-pythia8\n\n";
     exit 1;
  }
}

# If --enable-pythia8 was set then the full path to the PYTHIA8 includes must be specified
#
my $gopt_with_pythia8_inc = "";
if($gopt_enable_pythia8 eq "YES") {
  if(($match = grep(/--with-pythia8-inc/i, @ARGV)) > 0) {
    $options=~m/--with-pythia8-inc=(\S*)/i;
    $gopt_with_pythia8_inc = $1;
  }
  if(! -d $gopt_with_pythia8_inc)  {
    print "\n*** Warning *** PYTHIA8 has been enabled but you didn't specify the PYTHIA8 include path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_pythia8_inc eq "" && defined $ENV{'PYTHIA8_INC'}) {
     $gopt_with_pythia8_inc = $ENV{'PYTHIA8_INC'};
     print "The \$PHTHIA8_INC env var is defined. I will pick that and use --with-pythia8-inc=$gopt_with_pythia8_inc\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_pythia8_inc && $auto_detect)  {
    print "Auto-detecting the PYTHIA8 include path...\n";
    $matched = auto_detect("Pythia.h","Pythia8/Pythia.h");
    print "$gopt_with_pythia8_inc  \n";
    if( $matched=~m/(\S*)\/Pythia8\/Pythia.h/i ) {
       $gopt_with_pythia8_inc = $1;
    }
    print "Setting --with-pythia8-inc=$gopt_with_pythia8_inc\n";
  }
  # check
  my $file = "$gopt_with_pythia8_inc/Pythia8/Pythia.h";
  if(! -e $file) {
     print "*** Error *** You need to specify the PYTHIA8 includes path using --with-pythia8-inc=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-pythia8\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# LHAPDF5 paths
# ------------------------------------------------

# If --enable-lhapdf5 was set then the full path to the LHAPDF5 library must be specified
#
my $gopt_with_lhapdf5_lib = "";
if($gopt_enable_lhapdf5 eq "YES") {
  if(($match = grep(/--with-lhapdf5-lib/i, @ARGV)) > 0) {
    $options=~m/--with-lhapdf5-lib=(\S*)/i;
    $gopt_with_lhapdf5_lib = $1;
  }
  if(! -d $gopt_with_lhapdf5_lib)  {
    print "\n*** Warning *** LHAPDF5 has been enabled but you didn't specify the LHAPDF5 library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_lhapdf5_lib eq "" && defined $ENV{'LHAPDF5_LIB'}) {
     $gopt_with_lhapdf5_lib = $ENV{'LHAPDF5_LIB'};
     print "The \$LHAPDF5_LIB env var is defined. I will pick that and use --with-lhapdf5-lib=$gopt_with_lhapdf5_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_lhapdf5_lib && $auto_detect)  {
    print "Auto-detecting LHAPDF5 library path...\n";
    $matched = auto_detect("libLHAPDF.a");
    if( $matched=~m/(\S*)\/libLHAPDF.a/i ) {
       $gopt_with_lhapdf5_lib = $1;
    }
    print "Setting --with-lhapdf5-lib=$gopt_with_lhapdf5_lib\n";
  }
  # check
  my $fileso    = "$gopt_with_lhapdf5_lib/libLHAPDF.so";
  my $filedylib = "$gopt_with_lhapdf5_lib/libLHAPDF.dylib";
  if(! -e $fileso && ! -e $filedylib) {
     print "*** Error *** You need to specify the path to LHAPDF5 library using --with-lhapdf5-lib=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-lhapdf5\n\n";
     exit 1;
  }
}

# If --enable-lhapdf5 was set then the full path to the LHAPDF5 includes must be specified
#
my $gopt_with_lhapdf5_inc = "";
if($gopt_enable_lhapdf5 eq "YES") {
  if(($match = grep(/--with-lhapdf5-inc/i, @ARGV)) > 0) {
    $options=~m/--with-lhapdf5-inc=(\S*)/i;
    $gopt_with_lhapdf5_inc = $1;
  }
  if(! -d $gopt_with_lhapdf5_inc)  {
    print "\n*** Warning *** LHAPDF5 has been enabled but you didn't specify the LHAPDF5 include path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_lhapdf5_inc eq "" && defined $ENV{'LHAPDF5_INC'}) {
     $gopt_with_lhapdf5_inc = $ENV{'LHAPDF5_INC'};
     print "The \$LHAPDF5_INC env var is defined. I will pick that and use --with-lhapdf5-inc=$gopt_with_lhapdf5_inc\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_lhapdf5_inc && $auto_detect)  {
    print "Auto-detecting the LHAPDF5 include path...\n";
    $matched = auto_detect("LHAPDF.h","LHAPDF/LHAPDF.h");
    print "$gopt_with_lhapdf5_inc  \n";
    if( $matched=~m/(\S*)\/LHAPDF\/LHAPDF.h/i ) {
       $gopt_with_lhapdf5_inc = $1;
    }
    print "Setting --with-lhapdf5-inc=$gopt_with_lhapdf5_inc\n";
  }
  # check
  my $file = "$gopt_with_lhapdf5_inc/LHAPDF/LHAPDF.h";
  if(! -e $file) {
     print "*** Error *** You need to specify the LHAPDF5 includes path using --with-lhapdf5-inc=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-lhapdf5\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# LHAPDF6 paths
# ------------------------------------------------

# If --enable-lhapdf6 was set then the full path to the LHAPDF6 library must be specified
#
my $gopt_with_lhapdf6_lib = "";
if($gopt_enable_lhapdf6 eq "YES") {
  if(($match = grep(/--with-lhapdf6-lib/i, @ARGV)) > 0) {
    $options=~m/--with-lhapdf6-lib=(\S*)/i;
    $gopt_with_lhapdf6_lib = $1;
  }
  if(! -d $gopt_with_lhapdf6_lib)  {
    print "\n*** Warning *** LHAPDF6 has been enabled but you didn't specify the LHAPDF6 library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_lhapdf6_lib eq "" && defined $ENV{'LHAPDF6_LIB'}) {
     $gopt_with_lhapdf6_lib = $ENV{'LHAPDF6_LIB'};
     print "The \$LHAPDF6_LIB env var is defined. I will pick that and use --with-lhapdf6-lib=$gopt_with_lhapdf6_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_lhapdf6_lib && $auto_detect)  {
    print "Auto-detecting LHAPDF6 library path...\n";
    $matched = auto_detect("libLHAPDF.a");
    if( $matched=~m/(\S*)\/libLHAPDF.a/i ) {
       $gopt_with_lhapdf6_lib = $1;
    }
    print "Setting --with-lhapdf6-inc=$gopt_with_lhapdf6_lib\n";
  }
  # check
  my $fileso    = "$gopt_with_lhapdf6_lib/libLHAPDF.so";
  my $filedylib = "$gopt_with_lhapdf6_lib/libLHAPDF.dylib";
  if(! -e $fileso && ! -e $filedylib) {
     print "*** Error *** You need to specify the path to LHAPDF6 library using --with-lhapdf6-lib=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-lhapdf6\n\n";
     exit 1;
  }
}

# If --enable-lhapdf6 was set then the full path to the LHAPDF6 includes must be specified
#
my $gopt_with_lhapdf6_inc = "";
if($gopt_enable_lhapdf6 eq "YES") {
  if(($match = grep(/--with-lhapdf6-inc/i, @ARGV)) > 0) {
    $options=~m/--with-lhapdf6-inc=(\S*)/i;
    $gopt_with_lhapdf6_inc = $1;
  }
  if(! -d $gopt_with_lhapdf6_inc)  {
    print "\n*** Warning *** LHAPDF6 has been enabled but you didn't specify the LHAPDF6 include path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_lhapdf6_inc eq "" && defined $ENV{'LHAPDF6_INC'}) {
     $gopt_with_lhapdf6_inc = $ENV{'LHAPDF6_INC'};
     print "The \$LHAPDF6_INC env var is defined. I will pick that and use --with-lhapdf6-inc=$gopt_with_lhapdf6_inc\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_lhapdf6_inc && $auto_detect)  {
    print "Auto-detecting the LHAPDF6 include path...\n";
    $matched = auto_detect("LHAPDF.h","LHAPDF/LHAPDF.h");
    print "$gopt_with_lhapdf6_inc  \n";
    if( $matched=~m/(\S*)\/LHAPDF\/LHAPDF.h/i ) {
       $gopt_with_lhapdf6_inc = $1;
    }
    print "Setting --with-lhapdf6-inc=$gopt_with_lhapdf6_inc\n";
  }
  # check
  my $file = "$gopt_with_lhapdf6_inc/LHAPDF/LHAPDF.h";
  if(! -e $file) {
     print "*** Error *** You need to specify the LHAPDF6 includes path using --with-lhapdf6-inc=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-lhapdf6\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# APFEL paths
# ------------------------------------------------

# If --enable-apfel was set then the full path to the APFEL library must be specified
#
my $gopt_with_apfel_lib = "";
if($gopt_enable_apfel eq "YES") {
  if(($match = grep(/--with-apfel-lib/i, @ARGV)) > 0) {
    $options=~m/--with-apfel-lib=(\S*)/i;
    $gopt_with_apfel_lib = $1;
  }
  if(! -d $gopt_with_apfel_lib)  {
    print "\n*** Warning *** APFEL has been enabled but you didn't specify the APFEL library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_apfel_lib eq "" && defined $ENV{'APFEL_LIB'}) {
     $gopt_with_apfel_lib = $ENV{'APFEL_LIB'};
     print "The \$APFEL_LIB env var is defined. I will pick that and use --with-apfel-lib=$gopt_with_apfel_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_apfel_lib && $auto_detect)  {
    print "Auto-detecting APFEL library path...\n";

    my $matchfile = "";
    my @apfel_candidates = ("libAPFEL.so", "libAPFEL.a", "libAPFEL.la");

    foreach my $cand (@apfel_candidates) {
      $matched = auto_detect($cand);
      if(defined $matched && $matched ne "") {
        $matchfile = $matched;
        last;
      }
    }

    if($matchfile =~ m{(\S*)/libAPFEL\.(?:so|a|la)}i) {
      $gopt_with_apfel_lib = $1;
      print "Setting --with-apfel-lib=$gopt_with_apfel_lib\n";
    }
  }

  # check for APFEL libraries
  my $file_so = "$gopt_with_apfel_lib/libAPFEL.so";
  my $file_a  = "$gopt_with_apfel_lib/libAPFEL.a";
  my $file_la = "$gopt_with_apfel_lib/libAPFEL.la";
  
  if(! -e $file_so && ! -e $file_a && ! -e $file_la) {
      print "*** Error *** Could not find libAPFEL.[so|a|la] in $gopt_with_apfel_lib\n";
      print "*** Error *** You need to specify the path to APFEL library using --with-apfel-lib=/some/path/\n";
      print "*** Error *** Otherwise, you should --disable-apfel\n\n";
      exit 1;
  }
}

# If --enable-apfel was set then the full path to the APFEL includes must be specified
#
my $gopt_with_apfel_inc = "";
if($gopt_enable_apfel eq "YES") {
  if(($match = grep(/--with-apfel-inc/i, @ARGV)) > 0) {
    $options=~m/--with-apfel-inc=(\S*)/i;
    $gopt_with_apfel_inc = $1;
  }
  if(! -d $gopt_with_apfel_inc)  {
    print "\n*** Warning *** APFEL has been enabled but you didn't specify the APFEL include path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_apfel_inc eq "" && defined $ENV{'APFEL_INC'}) {
     $gopt_with_apfel_inc = $ENV{'APFEL_INC'};
     print "The \$APFEL_INC env var is defined. I will pick that and use --with-apfel-inc=$gopt_with_apfel_inc\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_apfel_inc && $auto_detect)  {
    print "Auto-detecting the APFEL include path...\n";
    $matched = auto_detect("APFEL.h","APFEL/APFEL.h");
    if( $matched=~m/(\S*)\/APFEL\/APFEL.h/i ) {
       $gopt_with_apfel_inc = $1;
    }
    print "Setting --with-apfel-inc=$gopt_with_apfel_inc\n";
  }
  # check
  my $file = "$gopt_with_apfel_inc/APFEL/APFEL.h";
  if(! -e $file) {
     print "*** Error *** You need to specify the APFEL includes path using --with-apfel-inc=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-apfel\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# LIBXML2 paths
# ------------------------------------------------

my $gopt_with_libxml2_inc = "";
my $gopt_with_libxml2_lib = "";

#
# --with-libxml2-inc=
#
if($options=~m/--with-libxml2-inc=(\S*)/i) {
  $gopt_with_libxml2_inc = $1;
}
if(! -d $gopt_with_libxml2_inc && $auto_detect)  {
  print "\n*** Warning *** You didn't specify the libxml2 include path \n";
  print "Auto-detecting...\n";
  $matched = auto_detect("xmlmemory.h");
  if( $matched=~m/(\S*)\/libxml\/xmlmemory.h/i ) {
     $gopt_with_libxml2_inc = $1;
  }
  print "Setting --with-libxml2-inc=$gopt_with_libxml2_inc\n";
}
if(! -d $gopt_with_libxml2_inc) {
  print "*** Error *** You need to specify the libxml2 include path using --with-libxml2-inc=/some/path/\n\n";
  exit 1;
}

#
# --with-libxml2-lib=
#
if($options=~m/--with-libxml2-lib=(\S*)/i) {
  $gopt_with_libxml2_lib = $1;
}
if(! -d $gopt_with_libxml2_lib && $auto_detect)  {
  print "\n*** Warning *** You didn't specify the libxml2 library path \n";
  print "Auto-detecting...\n";
  $matched = auto_detect("libxml2.*");
  if( $matched=~m/(\S*)\/libxml2\S*/i ) {
     $gopt_with_libxml2_lib = $1;
  }
  print "Setting --with-libxml2-lib=$gopt_with_libxml2_lib\n";
}
if(! -d $gopt_with_libxml2_lib) {
  print "*** Error *** You need to specify the libxml2 library path using --with-libxml2-lib=/some/path/\n\n";
  exit 1;
}

# ------------------------------------------------
# LOG4CPP paths
# ------------------------------------------------

my $gopt_with_log4cpp_inc = "";
my $gopt_with_log4cpp_lib = "";

#
# --with-log4cpp-inc=
#
if($options=~m/--with-log4cpp-inc=(\S*)/i) {
  $gopt_with_log4cpp_inc = $1;
}
if(! -d $gopt_with_log4cpp_inc && $auto_detect)  {
  print "\n*** Warning *** You didn't specify the log4cpp include path \n";
  print "Auto-detecting...\n";
  $matched = auto_detect("OstreamAppender.hh");
  if( $matched=~m/(\S*)\/log4cpp\/OstreamAppender.hh/i ) {
     $gopt_with_log4cpp_inc = $1;
  }
  print "Setting --with-log4cpp-inc=$gopt_with_log4cpp_inc\n";
}
if(! -d $gopt_with_log4cpp_inc) {
  print "*** Error *** You need to specify the log4cpp include path using --with-log4cpp-inc=/some/path/\n\n";
  exit 1;
}

#
# --with-log4cpp-lib=
#
if($options=~m/--with-log4cpp-lib=(\S*)/i) {
  $gopt_with_log4cpp_lib = $1;
}
if(! -d $gopt_with_log4cpp_lib && $auto_detect)  {
  print "\n*** Warning *** You didn't specify the log4cpp library path \n";
  print "Auto-detecting...\n";
  $matched = auto_detect("liblog4cpp.*");
  if( $matched=~m/(\S*)\/liblog4cpp\S*/i ) {
     $gopt_with_log4cpp_lib = $1;
  }
  print "Setting --with-log4cpp-lib=$gopt_with_log4cpp_lib\n";
}
if(! -d $gopt_with_log4cpp_lib) {
  print "*** Error *** You need to specify the log4cpp library path using --with-log4cpp-lib=/some/path/\n\n";
  exit 1;
}

# ------------------------------------------------
# INCL path
# ------------------------------------------------

# If --enable-incl was set then the full path to the INCL library must be specified
my $gopt_with_incl_lib = "";
if($gopt_enable_incl eq "YES") {
  if(($match = grep(/--with-incl-lib/i, @ARGV)) > 0) {
    $options=~m/--with-incl-lib=(\S*)/i;
    $gopt_with_incl_lib = $1;
  }
  if(! -d $gopt_with_incl_lib)  {
    print "\n*** Warning *** INCL has been enabled but you didn't specify the INCL library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_incl_lib eq "" && defined $ENV{'INCL_LIB'}) {
    $gopt_with_incl_lib = $ENV{'INCL_LIB'};
    print "The \$INCL_LIB env var is defined. I will pick that and use --with-incl-lib=$gopt_with_incl_lib\n";
  }

  # check
  my $fileso    = "$gopt_with_incl_lib/libINCL_Physics.so";
  my $filea = "$gopt_with_incl_lib/libINCL_Physics.a";
  if(! -e $fileso && ! -e $filea) {
    print "*** Error *** You need to specify the path to libINCL_Physics using --with-incl-lib=/some/path/\n";
    print "*** Error *** Otherwise, you should --disable-incl\n\n";
    exit 1;
  }
}

# If --enable-incl was set then the full path to the INCL includes must be specified
my $gopt_with_incl_inc = "";
if($gopt_enable_incl eq "YES") {
  if(($match = grep(/--with-incl-inc/i, @ARGV)) > 0) {
    $options=~m/--with-incl-inc=(\S*)/i;
    $gopt_with_incl_inc = $1;
  }
  if(! -d $gopt_with_incl_inc)  {
    print "\n*** Warning *** INCL has been enabled but you didn't specify the INCL includes path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_incl_inc eq "" && defined $ENV{'INCL_INC'}) {
    $gopt_with_incl_inc = $ENV{'INCL_INC'};
    print "The \$INCL_INC env var is defined. I will pick that and use --with-incl-inc=$gopt_with_incl_inc\n";
  }

  # check
  my $file = "$gopt_with_incl_inc/G4INCLCascade.hh";
  if(! -e $file) {
    print "*** Error *** You need to specify the path to G4INCLCascade.hh using --with-incl-inc=/some/path/\n";
    print "*** Error *** Otherwise, you should --disable-incl\n\n";
    exit 1;
  }
}

# ------------------------------------------------
# boost path
# ------------------------------------------------

# If --enable-incl was set then the full path to the boost library must also be specified
my $gopt_with_boost_lib = "";
if($gopt_enable_incl eq "YES") {
  if(($match = grep(/--with-boost-lib/i, @ARGV)) > 0) {
    $options=~m/--with-boost-lib=(\S*)/i;
    $gopt_with_boost_lib = $1;
  }
  if(! -d $gopt_with_boost_lib)  {
    print "\n*** Warning *** INCL has been enabled but you didn't specify the boost library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_boost_lib eq "" && defined $ENV{'BOOST_LIB'}) {
    $gopt_with_boost_lib = $ENV{'BOOST_LIB'};
    print "The \$BOOST_LIB env var is defined. I will pick that and use --with-boost-lib=$gopt_with_boost_lib\n";
  }

  # check
  my $fileso = "$gopt_with_boost_lib/libboost_program_options.so";
  my $filea  = "$gopt_with_boost_lib/libboost_program_options.a";
  if(! -e $fileso && ! -e $filea) {
    print "*** Error *** You need to specify the path to libboost_program_options.so using --with-boost-lib=/some/path/\n";
    print "*** Error *** Otherwise, you should --disable-incl\n\n";
    exit 1;
  }
}

# If --enable-incl was set then the full path to the boost includes must also be specified
my $gopt_with_boost_inc = "";
if($gopt_enable_incl eq "YES") {
  if(($match = grep(/--with-boost-inc/i, @ARGV)) > 0) {
    $options=~m/--with-boost-inc=(\S*)/i;
    $gopt_with_boost_inc = $1;
  }
  if(! -d $gopt_with_boost_inc)  {
    print "\n*** Warning *** INCL has been enabled but you didn't specify the boost includes path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_boost_inc eq "" && defined $ENV{'BOOST_INC'}) {
    $gopt_with_boost_inc = $ENV{'BOOST_INC'};
    print "The \$BOOST_INC env var is defined. I will pick that and use --with-boost-inc=$gopt_with_boost_inc\n";
  }

  # check
  my $file = "$gopt_with_boost_inc/boost/program_options.hpp";
  if(! -e $file) {
    print "*** Error *** You need to specify the path to boost/program_options.hpp using --with-boost-inc=/some/path/\n";
    print "*** Error *** Otherwise, you should --disable-incl\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# geant4 path
# ------------------------------------------------

# If --enable-geant4 was set then the full path to the Geant4 libraries must be specified
#
my $gopt_with_geant4_lib = "";
if($gopt_enable_geant4_interface eq "YES") {
  if(($match = grep(/--with-geant4-lib/i, @ARGV)) > 0) {
    $options=~m/--with-geant4-lib=(\S*)/i;
    $gopt_with_geant4_lib = $1;
  }
  if(! -d $gopt_with_geant4_lib)  {
    print "\n*** Warning *** Geant4 has been enabled but you didn't specify the Geant4 library path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_geant4_lib eq "" && defined $ENV{'GEANT4_LIB'}) {
     $gopt_with_geant4_lib = $ENV{'GEANT4_LIB'};
     print "The \$GEANT4_LIB env var is defined. I will pick that and use --with-geant4-lib=$gopt_with_geant4_lib\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_geant4_lib && $auto_detect)  {
    print "Auto-detecting GEANT4 library path...\n";
    $matched = auto_detect("libG4processes.so");
    if( $matched=~m/(\S*)\/libG4processes.so/i ) {
       $gopt_with_geant4_lib = $1;
    }
    print "Setting --with-geant4-lib=$gopt_with_geant4_lib\n";
  }
  # check
  my $fileso    = "$gopt_with_geant4_lib/libG4processes.so";
  my $filedylib = "$gopt_with_geant4_lib/libG4processes.dylib";
  if(! -e $fileso && ! -e $filedylib) {
     print "*** Error *** You need to specify the path to GEANT4 library using --with-geant4-lib=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-geant4\n\n";
     exit 1;
  }
}

# If --enable-geant4 was set then the full path to the GEANT4 includes must be specified
#
my $gopt_with_geant4_inc = "";
if($gopt_enable_geant4_interface eq "YES") {
  if(($match = grep(/--with-geant4-inc/i, @ARGV)) > 0) {
    $options=~m/--with-geant4-inc=(\S*)/i;
    $gopt_with_geant4_inc = $1;
  }
  if(! -d $gopt_with_geant4_inc)  {
    print "\n*** Warning *** GEANT4 has been enabled but you didn't specify the GEANT4 include path \n";
  }
  # if it was not set, try to pick it up from the environment
  if($gopt_with_geant4_inc eq "" && defined $ENV{'GEANT4_INC'}) {
     $gopt_with_geant4_inc = $ENV{'GEANT4_INC'};
     print "The \$GEANT4_INC env var is defined. I will pick that and use --with-geant4-inc=$gopt_with_geant4_inc\n";
  }
  # if it still not set, try autodetecting it
  if(! -d $gopt_with_geant4_inc && $auto_detect)  {
    print "Auto-detecting the GEANT4 include path...\n";
    $matched = auto_detect("G4Run.hh","Geant4/G4Run.hh");
    print "$gopt_with_geant4_inc  \n";
    if( $matched=~m/(\S*)\/Geant4\/G4Run.hh/i ) {
       $gopt_with_geant4_inc = $1;
    }
    print "Setting --with-geant4-inc=$gopt_with_geant4_inc\n";
  }
  # check
  my $file = "$gopt_with_geant4_inc/Geant4/G4Run.hh";
  if(! -e $file) {
     print "*** Error *** You need to specify the GEANT4 includes path using --with-geant4-inc=/some/path/\n";
     print "*** Error *** Otherwise, you should --disable-geant4\n\n";
     exit 1;
  }
}

# ------------------------------------------------
# libgfortran path
# ------------------------------------------------

my $gopt_with_gfortran_lib = "";

if($gopt_enable_gfortran eq "YES") {

  if($options=~m/--with-gfortran-lib=(\S*)/i) {
    $gopt_with_gfortran_lib = $1;
  }
  if(! -d $gopt_with_gfortran_lib && $auto_detect)  {
    print "\n*** Warning *** You didn't specify the gfortran library path \n";
    print "Auto-detecting...\n";
    $matched = auto_detect("libgfortran.*");
    if( $matched=~m/(\S*)\/libgfortran\S*/i ) {
       $gopt_with_gfortran_lib = $1;
    }
    print "Setting --with-gfortran-lib=$gopt_with_gfortran_lib\n";
  }
  if(! -d $gopt_with_gfortran_lib) {
    print "*** Error *** You need to specify the gfortran library path using --with-gfortran-lib=/some/path/\n\n";
    exit 1;
  }
}

# ------------------------------------------------
# libg2c path
# ------------------------------------------------

my $gopt_with_g2c_lib = "";

if($gopt_enable_g2c eq "YES") {

  if($options=~m/--with-g2c-lib=(\S*)/i) {
    $gopt_with_g2c_lib = $1;
  }
  if(! -d $gopt_with_g2c_lib && $auto_detect)  {
    print "\n*** Warning *** You didn't specify the g2c library path \n";
    print "Auto-detecting...\n";
    $matched = auto_detect("libg2c.*");
    if( $matched=~m/(\S*)\/libg2c\S*/i ) {
       $gopt_with_g2c_lib = $1;
    }
    print "Setting --with-g2c-lib=$gopt_with_g2c_lib\n";
  }
  if(! -d $gopt_with_g2c_lib) {
    print "*** Error *** You need to specify the g2c library path using --with-g2c-lib=/some/path/\n\n";
    exit 1;
  }
}

# ------------------------------------------------
# Professor2 submode checkout
# ------------------------------------------------
if ($gopt_enable_professor2 eq "YES") {
  #run git submodule update src/ExternalLibs/professor
  print "Checking out Professor2 submodule...\n";
  system("git submodule update --init src/ExternalLibs/professor");
  print "Done.\n";
}

# Save config options
#
print MKCONF "GOPT_ENABLE_PYTHIA6=$gopt_enable_pythia6\n";
print MKCONF "GOPT_ENABLE_PYTHIA8=$gopt_enable_pythia8\n";
print MKCONF "GOPT_ENABLE_INCL=$gopt_enable_incl\n";
print MKCONF "GOPT_ENABLE_GEANT4_INTERFACE=$gopt_enable_geant4_interface\n";
print MKCONF "GOPT_ENABLE_LHAPDF5=$gopt_enable_lhapdf5\n";
print MKCONF "GOPT_ENABLE_LHAPDF6=$gopt_enable_lhapdf6\n";
print MKCONF "GOPT_ENABLE_APFEL=$gopt_enable_apfel\n";
print MKCONF "GOPT_ENABLE_FLUX_DRIVERS=$gopt_enable_flux_drivers\n";
print MKCONF "GOPT_ENABLE_GEOM_DRIVERS=$gopt_enable_geom_drivers\n";
print MKCONF "GOPT_ENABLE_T2K=$gopt_enable_t2k\n";
print MKCONF "GOPT_ENABLE_FNAL=$gopt_enable_fnal\n";
print MKCONF "GOPT_ENABLE_ATMO=$gopt_enable_atmo\n";
print MKCONF "GOPT_ENABLE_NUCLEON_DECAY=$gopt_enable_nucleon_decay\n";
print MKCONF "GOPT_ENABLE_NNBAR_OSCILLATION=$gopt_enable_nnbar_oscillation\n";
print MKCONF "GOPT_ENABLE_BOOSTED_DARK_MATTER=$gopt_enable_boosted_dark_mat\n";
print MKCONF "GOPT_ENABLE_HEAVY_NEUTRAL_LEPTON=$gopt_enable_heavy_neutral_lepton\n";
print MKCONF "GOPT_ENABLE_HNL_VALIDATION=$gopt_enable_hnl_validation\n";
print MKCONF "GOPT_ENABLE_DARK_NEUTRINO=$gopt_enable_dark_neutrino\n";
print MKCONF "GOPT_ENABLE_EVTLIB=$gopt_enable_evtlib\n";
print MKCONF "GOPT_ENABLE_INCL=$gopt_enable_incl\n";
print MKCONF "GOPT_ENABLE_GEANT4_INTERFACE=$gopt_enable_geant4_interface\n";
print MKCONF "GOPT_ENABLE_MASTERCLASS=$gopt_enable_masterclass\n";
print MKCONF "GOPT_ENABLE_TEST=$gopt_enable_test\n";
print MKCONF "GOPT_ENABLE_DYLIBVERSION=$gopt_enable_dylibversion\n";
print MKCONF "GOPT_ENABLE_LOW_LEVEL_MESG=$gopt_enable_lowlevel_mesg\n";
print MKCONF "GOPT_ENABLE_PROFILER=$gopt_enable_profiler\n";
print MKCONF "GOPT_ENABLE_DOXYGEN_DOC=$gopt_enable_doxygen_doc\n";
print MKCONF "GOPT_ENABLE_GFORTRAN=$gopt_enable_gfortran\n";
print MKCONF "GOPT_ENABLE_G2C=$gopt_enable_g2c\n";
print MKCONF "GOPT_ENABLE_PROFESSOR2=$gopt_enable_professor2\n";
print MKCONF "GOPT_WITH_COMPILER=$gopt_with_compiler\n";
print MKCONF "GOPT_WITH_CXX_DEBUG_FLAG=$gopt_with_cxx_debug_flag\n";
print MKCONF "GOPT_WITH_CXX_OPTIMIZ_FLAG=-$gopt_with_cxx_optimiz_flag\n";
print MKCONF "GOPT_WITH_PROFILER_LIB=$gopt_with_profiler_lib\n";
print MKCONF "GOPT_WITH_DOXYGEN_PATH=$gopt_with_doxygen_path\n";
print MKCONF "GOPT_WITH_PYTHIA6_LIB=$gopt_with_pythia6_lib\n";
print MKCONF "GOPT_WITH_PYTHIA8_LIB=$gopt_with_pythia8_lib\n";
print MKCONF "GOPT_WITH_PYTHIA8_INC=$gopt_with_pythia8_inc\n";
print MKCONF "GOPT_WITH_LHAPDF5_LIB=$gopt_with_lhapdf5_lib\n";
print MKCONF "GOPT_WITH_LHAPDF5_INC=$gopt_with_lhapdf5_inc\n";
print MKCONF "GOPT_WITH_LHAPDF6_LIB=$gopt_with_lhapdf6_lib\n";
print MKCONF "GOPT_WITH_LHAPDF6_INC=$gopt_with_lhapdf6_inc\n";
print MKCONF "GOPT_WITH_APFEL_LIB=$gopt_with_apfel_lib\n";
print MKCONF "GOPT_WITH_APFEL_INC=$gopt_with_apfel_inc\n";
print MKCONF "GOPT_WITH_LIBXML2_INC=$gopt_with_libxml2_inc\n";
print MKCONF "GOPT_WITH_LIBXML2_LIB=$gopt_with_libxml2_lib\n";
print MKCONF "GOPT_WITH_LOG4CPP_INC=$gopt_with_log4cpp_inc\n";
print MKCONF "GOPT_WITH_LOG4CPP_LIB=$gopt_with_log4cpp_lib\n";
print MKCONF "GOPT_WITH_INCL_INC=$gopt_with_incl_inc\n";
print MKCONF "GOPT_WITH_INCL_LIB=$gopt_with_incl_lib\n";
print MKCONF "GOPT_WITH_BOOST_INC=$gopt_with_boost_inc\n";
print MKCONF "GOPT_WITH_BOOST_LIB=$gopt_with_boost_lib\n";
print MKCONF "GOPT_WITH_GEANT4_INC=$gopt_with_geant4_inc\n";
print MKCONF "GOPT_WITH_GEANT4_LIB=$gopt_with_geant4_lib\n";
print MKCONF "GOPT_WITH_GFORTRAN_LIB=$gopt_with_gfortran_lib\n";
print MKCONF "GOPT_WITH_G2C_LIB=$gopt_with_g2c_lib\n";
close(MKCONF);

print "\nYour input configuration options were: @ARGV";
if($#ARGV < 0) { print "(none)" };
print "\n\n";

if(-e $MKCONF_FILE) {
  print "The $MKCONF_FILE file has been succesfully generated! \n";
  print "The following config options were set: \n";

  open(MKCONFR, "<$MKCONF_FILE") or die("Can not read back the $GENIE/src/make/Make.config!");
  @make_conf=<MKCONFR>;
  close(MKCONFR);
# print "@make_conf\n" unless ;
  foreach $setting (@make_conf) {
    chomp($setting);
    if ($setting=~m/\=/) {print "  $setting\n";}
  }

  # Copy only the enable/disable options, excluding paths, in a separate file for genie-config.
  # This is needed for FNAL relocatable releases.
  system("cat $MKCONF_FILE | grep GOPT_ENABLE_ > $MKCONF_FILE\_no_paths");

  print "\n";
  print "*** To continue building GENIE type: make ";
  # Warning for SRT users
  if(defined $ENV{'SRT_ENV_SET'}) {
    print "(Don't forget to 'srt_setup --unsetup' first)";
  }
  print "\n\n";

  exit 0;
}

sub auto_detect {

  # First place to look when autodetecting is in the directories in LD_LIBRARY_PATH
  my @libdirs = ( );
  push (@libdirs,split(":",$ENV{LD_LIBRARY_PATH}))    if defined $ENV{LD_LIBRARY_PATH};
  push (@libdirs,split(":",$ENV{DYLD_LIBRARY_PATH}))  if defined $ENV{DYLD_LIBRARY_PATH}; #and the mac equivalent
  my @search_dir = ();
  foreach my $libdir (unique_entries(@libdirs)) {
    chomp($libdir);
    if (not $libdir) {next;}
    push (@search_dir, $libdir); # Append the LD library path directory
    @pathdirs = split("/",$libdir);
    $lastdir = pop(@pathdirs);
    $basedir = join("/",@pathdirs);
    if ($lastdir =~ m/lib/) {# If the LD_LIBRARY_PATH has "lib" in it, append "../include"
      push (@search_dir, $basedir."/include");
    }
  }
  # and standard search paths
  push (@search_dir,"/usr");
  push (@search_dir,"/lib");
  push (@search_dir,"/opt");
  push (@search_dir,"/hep");
  push (@search_dir,"/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/");
  push (@search_dir,"$ENV{'HOME'}")
                 if defined $ENV{'HOME'};          # add $HOME
  push (@search_dir,"/hep");                       # add where I add ext apps in my mac book air
  push (@search_dir,"$ENV{'RSD_TOP_DIR'}")
                 if defined $ENV{'RSD_TOP_DIR'};   # add where RSD puts ext supporting libs

  @search_dir = unique_entries(@search_dir); # Search each dir only once

  $search_file = shift;
  $optional_fullpath_substr = shift; # extra help in locating the correct file

  $optional_fullpath_substr = "" unless defined $optional_fullpath_substr;

  foreach(@search_dir) {
     $curr_dir = $_;
     if(! -d $curr_dir) {next;}
     @matches = `find $curr_dir/ -type f -maxdepth 7 -name \"$search_file\" 2> /dev/null | grep \"$optional_fullpath_substr\"`;
     $nmatches = @matches;
     if( $nmatches > 0) { return $matches[0]; }
  }
  return "";
}

# Get unique entries in an array
sub unique_entries {
  my %seen;
  return grep { !$seen{$_}++ } @_;
}