Eclipse CDT Autocomplete not working

Question

I remember from some time ago that Eclipse had auto-complete when you type, and now I can only get it when pressing Ctrl + Space. I already checked and

Answer 1

I had a problem with Eclipse Juno (OSX Java "1.6.0_33") where the autocomplete (and save key binding) wasn't working properly. Googling I found this: Eclipse JUNO doesn't start

Updating my Mercurial Plugin to the latest (1.9.1) fixed both these issues for me.

Very weird.