Fix Windows build break.
Fix Windows build break.

danluu/BitFunnel,danluu/BitFunnel,BitFunnel/BitFunnel,danluu/BitFunnel,danluu/BitFunnel,danluu/BitFunnel,BitFunnel/BitFunnel,BitFunnel/BitFunnel,BitFunnel/BitFunnel,danluu/BitFunnel,BitFunnel/BitFunnel,BitFunnel/BitFunnel