Eclipse Indigo CDT: Function could not be resolved

Question

This feels silly, but its been 2 days...somewhere after upgrading from Ubuntu 10.04 to 10.11 and from Eclipse Helios to Eclipse Indigo, I got stuck with the following problem:

Answer 1

That looks like a problem that many others have had with eclipse CDT before. Sometimes shutting eclipse down and then starting it back up again is enough to help. If that isn't the case, take a look at what I have below:

Compilation ok, but eclipse content assist having problems