fix toolchain location when using variants

parallel_emerge

 #!/usr/bin/python2.6
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Program to run emerge in parallel, for significant speedup.
 
 Usage:
  ./parallel_emerge [--board=BOARD] [--workon=PKGS] [--no-workon-deps]
                    [emerge args] package"
@@ skipping 259 matching lines @@
     # variables are normally setup inside emerge-${BOARD}, but since we don't
     # call that script, we have to set it up here. These variables serve to
     # point our tools at /build/BOARD and to setup cross compiles to the
     # appropriate board as configured in toolchain.conf.
     if self.board:
       os.environ["PORTAGE_CONFIGROOT"] = "/build/" + self.board
       os.environ["PORTAGE_SYSROOT"] = "/build/" + self.board
       os.environ["SYSROOT"] = "/build/" + self.board
       scripts_dir = os.path.dirname(os.path.realpath(__file__))
       toolchain_path = "%s/../overlays/overlay-%s/toolchain.conf"
-      f = open(toolchain_path % (scripts_dir, self.board))
+      # Strip the variant out of the board name to look for the toolchain. This
+      # is similar to what setup_board does.
+      board_no_variant = self.board.split('_')[0]
+      f = open(toolchain_path % (scripts_dir, board_no_variant))
       os.environ["CHOST"] = f.readline().strip()
       f.close()
 
       # Although CHROMEOS_ROOT isn't specific to boards, it's normally setup
       # inside emerge-${BOARD}, so we set it up here for compatibility. It
       # will be going away soon as we migrate to CROS_WORKON_SRCROOT.
       os.environ.setdefault("CHROMEOS_ROOT", os.environ["HOME"] + "/trunk")
 
     # Modify the environment to disable locking.
     os.environ["PORTAGE_LOCKS"] = "false"
@@ skipping 966 matching lines @@
       for db_pkg in final_db.match_pkgs(pkg):
         print "Adding %s to world" % db_pkg.cp
         new_world_pkgs.append(db_pkg.cp)
     if new_world_pkgs:
       world_set.update(new_world_pkgs)
 
   print "Done"
 
 if __name__ == "__main__":
   main()