[ns] Initialisation of TCP Agent variables

[Sven Ostring <ostrinsa@elec.canterbury.ac.nz>]

I'm developing a flavour of TCP based on the Reno Agent, but I'm having 
difficulty initialising variables for the basic TCP Agent.  Looking at 
NewReno, these initalisations are simply inherited from Reno, but I've 
also called the constructor for the Reno agent in the constructor for my 
agent:

NewTcpAgent::NewTcpAgent() : RenoTcpAgent(), variable(0), (etc...) 
{
  ...
}

However, it is obvious that variables are not being initialised.  For 
example:

tcp_tick_ = 
30460464189311453658435289295240275330842364727644021878483696509513970204
43825911518540508490602178676317619040026624.000000

t_backoff = -4275384
which results in the warning
TcpAgent: negative RTO! (-0.300000)

Where does initialisation occur if NewRenoTcpAgent() does not invoke 
RenoTcpAgent() which would invoke TcpAgent()?

Thanks,
Sven.