I think I have figure out what seems to be the problem. The parser would run endlessly somewhere, either at the current project directory or the entire GUI framework / compiler directory and would stuck in a place that is beyond my wildest imagination (LOL), and after reparsed my project memory returned to normal levels.
Also, when I use the auto completion with Ctrl-Space I get duplicate on top of duplicate for each class member, but class constructors / destructors are appeared only once.
Does this help a bit? Cheers to both of you for your valuable feedback.
@oBFusCATed: I will try this tomorrow on work's laptop, and when I get home tonight, I will try it on Debian too and let you know for sure.