old_contents: """SCons.Tool.allow_undefined
  
  This is NOT a tool.
  """
  
  #
  # __COPYRIGHT__
  #
  # Permission is hereby granted, free of charge, to any person obtaining
  # a copy of this software and associated documentation files (the
  # "Software"), to deal in the Software without restriction, including
  # without limitation the rights to use, copy, modify, merge, publish,
  # distribute, sublicense, and/or sell copies of the Software, and to
  # permit persons to whom the Software is furnished to do so, subject to
  # the following conditions:
  #
  # The above copyright notice and this permission notice shall be included
  # in all copies or substantial portions of the Software.
  #
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
  # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
  # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  #
  
  __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
  
  import os
  
  from subprocess import Popen, PIPE
  
  def get_darwin_version():
  
  	p = Popen(["sw_vers", "-productVersion"], stdout = PIPE, stderr = PIPE)
  	st = p.wait()
  	if st:
  		raise RuntimeError(
                  "Could not execute sw_vers -productVersion to get version")
  
  	verstring = p.stdout.next()
  	a, b, c = verstring.split(".")
  	try:
  		major = int(a)
  		minor = int(b)
  		micro = int(c)
  
  		return major, minor, micro
  	except ValueError:
  		raise ValueError("Could not parse version string %s" % verstring)
  
  def get_darwin_allow_undefined():
      """Return the list of flags to allow undefined symbols in a shared library.
  
      On MAC OS X, takes MACOSX_DEPLOYMENT_TARGET into account."""
      major, minor, micro = get_darwin_version()
      if major == 10:
          if minor < 3:
              flag = ["-Wl,-undefined", "-Wl,suppress"]
          else:
              try:
                  deptarget = os.environ['MACOSX_DEPLOYMENT_TARGET']
                  ma, mi = deptarget.split(".")
                  if mi < 3:
                      flag = ['-Wl,-flat_namespace', '-Wl,-undefined', '-Wl,suppress']
                  else:
                      flag = ['-Wl,-undefined', '-Wl,dynamic_lookup']
              except KeyError:
                  flag = ['-Wl,-flat_namespace', '-Wl,-undefined', '-Wl,suppress']
      else:
          # Non existing mac os x ? Just set to empty list
          flag = []
  
      return flag
  
new_contents: import os
  
  from subprocess import Popen, PIPE
  
  def get_darwin_version():
  
  	p = Popen(["sw_vers", "-productVersion"], stdout = PIPE, stderr = PIPE)
  	st = p.wait()
  	if st:
  		raise RuntimeError(
                  "Could not execute sw_vers -productVersion to get version")
  
  	verstring = p.stdout.next()
  	a, b, c = verstring.split(".")
  	try:
  		major = int(a)
  		minor = int(b)
  		micro = int(c)
  
  		return major, minor, micro
  	except ValueError:
  		raise ValueError("Could not parse version string %s" % verstring)
  
  def get_darwin_allow_undefined():
      """Return the list of flags to allow undefined symbols in a shared library.
  
      On MAC OS X, takes MACOSX_DEPLOYMENT_TARGET into account."""
      major, minor, micro = get_darwin_version()
      if major == 10:
          if minor < 3:
              flag = ["-Wl,-undefined", "-Wl,suppress"]
          else:
              try:
                  deptarget = os.environ['MACOSX_DEPLOYMENT_TARGET']
                  ma, mi = deptarget.split(".")
                  if mi < 3:
                      flag = ['-Wl,-flat_namespace', '-Wl,-undefined', '-Wl,suppress']
                  else:
                      flag = ['-Wl,-undefined', '-Wl,dynamic_lookup']
              except KeyError:
                  flag = ['-Wl,-flat_namespace', '-Wl,-undefined', '-Wl,suppress']
      else:
          # Non existing mac os x ? Just set to empty list
          flag = []
  
      return flag
  
subject: Remove inappropriate comments.