old_contents: ##############################################################################
  # Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # This program is distributed in the hope that it will be useful, but
  # WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  from spack import *
  import sys
  
  
  class Lz4(Package):
      """LZ4 is lossless compression algorithm, providing compression speed
      at 400 MB/s per core, scalable with multi-cores CPU. It also features
      an extremely fast decoder, with speed in multiple GB/s per core,
      typically reaching RAM speed limits on multi-core systems."""
  
      homepage = "http://lz4.github.io/lz4/"
      url      = "https://github.com/lz4/lz4/archive/v1.7.5.tar.gz"
  
      version('1.8.1.2', '343538e69ba752a386c669b1a28111e2')
      version('1.7.5', 'c9610c5ce97eb431dddddf0073d919b9')
      version('1.3.1', '42b09fab42331da9d3fb33bd5c560de9')
  
      # depends_on('valgrind', type='test')
  
      def url_for_version(self, version):
          url = "https://github.com/lz4/lz4/archive"
  
          if version > Version('1.3.1'):
              return "{0}/v{1}.tar.gz".format(url, version)
          else:
              return "{0}/r{1}.tar.gz".format(url, version.joined)
  
      def install(self, spec, prefix):
          make()
          if self.run_tests:
              make('test')  # requires valgrind to be installed
          make('install', 'PREFIX={0}'.format(prefix))
  
      @run_after('install')
      def darwin_fix(self):
          if sys.platform == 'darwin':
              fix_darwin_install_name(self.prefix.lib)
  
new_contents: ##############################################################################
  # Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # This program is distributed in the hope that it will be useful, but
  # WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  from spack import *
  import sys
  
  
  class Lz4(Package):
      """LZ4 is lossless compression algorithm, providing compression speed
      at 400 MB/s per core, scalable with multi-cores CPU. It also features
      an extremely fast decoder, with speed in multiple GB/s per core,
      typically reaching RAM speed limits on multi-core systems."""
  
      homepage = "http://lz4.github.io/lz4/"
      url      = "https://github.com/lz4/lz4/archive/v1.7.5.tar.gz"
  
      version('1.8.1.2', '343538e69ba752a386c669b1a28111e2')
      version('1.7.5', 'c9610c5ce97eb431dddddf0073d919b9')
      version('1.3.1', '42b09fab42331da9d3fb33bd5c560de9')
  
      # depends_on('valgrind', type='test')
  
      def url_for_version(self, version):
          url = "https://github.com/lz4/lz4/archive"
  
          if version > Version('1.3.1'):
              return "{0}/v{1}.tar.gz".format(url, version)
          else:
              return "{0}/r{1}.tar.gz".format(url, version.joined)
  
      def install(self, spec, prefix):
          if sys.platform != "darwin":
              make('LIBS=-lrt')  # fixes make error on CentOS6
          else:
              make()
          if self.run_tests:
              make('test')  # requires valgrind to be installed
          make('install', 'PREFIX={0}'.format(prefix))
  
      @run_after('install')
      def darwin_fix(self):
          if sys.platform == 'darwin':
              fix_darwin_install_name(self.prefix.lib)
  
subject: fix missing -lrt for Centos6, issue: #7552 (#7597)