If my RRSP contri room for 2018 =0 and I still contribute $5k in that but do not claim deduction while filing taxes for 2018 - will CRA trigger RRSP over-contri penalty ?

I am a new immigrant so my RRSP room =0 for 2018. 

 I still want to contribute to my employer provided registered group-rsp using payroll deduction so as to capture employer match amount.