diff -r 7e2b389418da -r 7825f6154a65 contrib/check-code.py
--- a/contrib/check-code.py	Fri May 20 09:47:35 2016 +0900
+++ b/contrib/check-code.py	Fri May 20 09:47:35 2016 +0900
@@ -622,7 +622,7 @@
 
     return result
 
-if __name__ == "__main__":
+def main():
     parser = optparse.OptionParser("%prog [options] [files]")
     parser.add_option("-w", "--warnings", action="store_true",
                       help="include warning-level checks")
@@ -650,4 +650,7 @@
                          blame=options.blame, debug=options.debug,
                          lineno=options.lineno):
             ret = 1
-    sys.exit(ret)
+    return ret
+
+if __name__ == "__main__":
+    sys.exit(main())