2 - Add preprocessor code
3 - proper handling of different file encodings, parsing non-ascii strings
6 - the expect macros abort functions directly. This leads to some functions
7 not resetting the current context properly (parse_for)
8 - label: declaration; is no valid C99 but we parse it anyway
9 - designator support for initializers
10 - add constant folding code
11 - Refactor code, so code to handle number values and strings is
12 an own module and replacable
15 - output source file positions for panics...