old_contents: GnuPackage ('tar', '1.26', override_properties = { 'build_dependency' : True })
  
new_contents: class TarPackage (GnuPackage):
  	def __init__ (self):
  		GnuPackage.__init__ (self, 'tar', '1.26',
  			configure_flags = [
  				'--enable-nls=no'
  			]
  		)
  
  TarPackage ()
  
subject: Build tar with --enable-nls=no, without this, it seems to crash when invoking gzip if LC_CTYPE/LANG are not set.