code: def find_binutils_libs(self, libdir, lib_ext):
          
          bfd_expr = re.compile("(lib(?:bfd)|(?:opcodes))(.*?)\%s" % lib_ext )
          libs = {}
          for root, dirs, files in os.walk(libdir):
              for f in files:
                  m = bfd_expr.search(f)
                  if m:
                      lib, version = m.groups()
                      fp = os.path.join(root, f)
                      if version in libs:
                          libs[ version ].append( fp )
                      else:
                          libs[ version ] = [fp,]
  
          # first, search for multiarch files.
          # check if we found more than one version of the multiarch libs.
          multiarch_libs = dict( [(v,_l) for v, _l in libs.items() \
              if v.find("multiarch") != -1 ] )
          if len(multiarch_libs) > 1:
          	print "[W] Multiple binutils versions detected. Trying to build with default..."
              	return multiarch_libs.values()[0]
          if len(multiarch_libs) == 1:
              return multiarch_libs.values()[0]
          # or use the default libs, or .. none
          return libs.get("",[])
docs: Find Binutils libraries.