Okay. I have encountered another strange issue.
When I declare a variable, let's say an integer called num. If I initialise it with the assignment operator, i.e. int num = 0;, then everything works fine.
However, if initialise it like this int num {0};, then codeblocks would not take that variable into consideration for code completion. If I type start typing the name of the variable, the auto code completion won't appear, and if I try to force it with Ctrl+Space, then codeblocks won't find it. Additionally, if the variable has methods, a string or a vector variable for instance, then none of these methods would show up, because the variable isn't even recognised as a variable.
Any ideas what is happening here?