In Engineering, Does the presence of rust have adverse impact to the bond performance of bar reinforcement?

In engineering rust ( little ) no problem , so more or extra allowed its problem 

Rebar needs a little rust, that means the protective skin of the rebar is gone. But excessive rust means that you basically have loose parts on the rebar so that will affect the bond negative

Yes the presence of rust have adverse impact to the bond performance of bar reinforcement with faster corrosion.

less rust is acceptable but more rust lead problem for the proper bonding.but no worry there is a anti corrosion chemical available in market.