Why is xCode running?

Question

macOS

Hello! In short, it's unrealistic to run xCode 6.4: Autocomplete does
n't work at all (only autocomplete variables);
Can't see classes
Errors are displayed only in the inspector, but do not show in the file;
When clicking on system classes, holding cmd does not open the file, writes (Missing symbol);
It feels like you are working in a notepad. Stupidly typing from memory ...
And this despite the fact that I have an iMac of 2014.
And here, the same xCode 6.4 flies on a "Hackintosh". Lenovo u410 (ultrabook). What could be the problem? xCode reinstalled several times.

Answer 1

Well, it's Xcode. He was always like that, windy and unpredictable :)