[click] usage of bighashmap in Click

[Alan Tang]

Dear everyone,

I found the use of bighashmap in SpinlockInfo the thing confuses me is SpinlockInfo::SpinlockInfo():_map(-1). I guess the constructor been called 
is HashMap(const HashMap<K, V> &); is that correct? What does _map(-1) initialize? 

Since HashMap uses template, I put  HashMap<unsigned, unsigned> _statistics; in my element class header file. Then I got 

/elements/standard/smartqueue.cc:12: undefined reference to `HashMap<unsigned int, unsigned int>::~HashMap(void)'

If I copy HashMap<String, int> _map; then there is no error. 

Thank you Eddi and Tolja for the previous replies. I really appreciate that.
Kind regards
Alan