No, smacking solves nothing. I might be in the minority but physically punishing a child truly isn't the solution if you try your best to be a good parent.
I was beaten properly, not a light tap but beaten. It solved nothing with me. I wasn't a bad kid, but
I did have bad parents who took their moods out on me and never once said they loved me. My father died last December, I hadn't seen him since I was 16 and didn't even bother to go to the funeral.
My own child I tell him I love him every single day of the week, he knows I am always there to back him up, and the once I shouted at him as a child through my own temper I still think about, and that was only shouting not hitting.
He doesn't drink, doesn't smoke, is very respectful, he isn't disobedient nor mollycoddled, he is a tough guy, sky-dived swam with sharks and suchlike. It's been a long uphill battle as his mum died in 2002, but she would be proud of how he has turned out.