Thanks for the bug report. Can you file it at
http://code.google.com/p/google-sparsehash/issues/list
so I can track it?
The simple solution for you, I believe, is to look for the line
#ifndef WIN32 // windows defines its own version
in hashtable_unittest.cc and change it to
#ifdef _MSC_VER // windows defines its own version
Let me know if that works for you.
craig