text: # -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
  
  from waflib import Logs, Configure
  
  def options(opt):
      opt.add_option('--debug', '--with-debug', action='store_true', default=False, dest='debug',
                     help='''Compile in debugging mode without optimizations (-O0 or -Og)''')
  
  def configure(conf):
      areCustomCxxflagsPresent = (len(conf.env.CXXFLAGS) > 0)
      defaultFlags = ['-std=c++0x', '-std=c++11',
                      '-stdlib=libc++',   # clang on OSX < 10.9 by default uses gcc's
                                          # libstdc++, which is not C++11 compatible
                      '-pedantic', '-Wall']
  
      if conf.options.debug:
          conf.define('_DEBUG', 1)
          defaultFlags += ['-O0',
                           '-Og', # gcc >= 4.8
                           '-g3',
                           '-fcolor-diagnostics', # clang
                           '-fdiagnostics-color', # gcc >= 4.9
                           '-Werror',
                           '-Wno-error=deprecated-register',
                          ]
          if areCustomCxxflagsPresent:
              missingFlags = [x for x in defaultFlags if x not in conf.env.CXXFLAGS]
              if len(missingFlags) > 0:
                  Logs.warn("Selected debug mode, but CXXFLAGS is set to a custom value '%s'"
                            % " ".join(conf.env.CXXFLAGS))
                  Logs.warn("Default flags '%s' are not activated" % " ".join(missingFlags))
          else:
              conf.add_supported_cxxflags(defaultFlags)
      else:
          defaultFlags += ['-O2', '-g']
          if not areCustomCxxflagsPresent:
              conf.add_supported_cxxflags(defaultFlags)
  
      # clang on OSX < 10.9 by default uses gcc's libstdc++, which is not C++11 compatible
      conf.add_supported_linkflags(['-stdlib=libc++'])
  
  @Configure.conf
  def add_supported_cxxflags(self, cxxflags):
      """
      Check which cxxflags are supported by compiler and add them to env.CXXFLAGS variable
      """
      self.start_msg('Checking supported CXXFLAGS')
  
      supportedFlags = []
      for flag in cxxflags:
          if self.check_cxx(cxxflags=['-Werror', flag], mandatory=False):
              supportedFlags += [flag]
  
      self.end_msg(' '.join(supportedFlags))
      self.env.CXXFLAGS = supportedFlags + self.env.CXXFLAGS
  
  @Configure.conf
  def add_supported_linkflags(self, linkflags):
      """
      Check which linkflags are supported by compiler and add them to env.LINKFLAGS variable
      """
      self.start_msg('Checking supported LINKFLAGS')
  
      supportedFlags = []
      for flag in linkflags:
          if self.check_cxx(linkflags=['-Werror', flag], mandatory=False):
              supportedFlags += [flag]
  
      self.end_msg(' '.join(supportedFlags))
      self.env.LINKFLAGS = supportedFlags + self.env.LINKFLAGS
  