Found due to %option nodefault. A match for } was actually missing
and # was not properly matched if it was part of an include statement
on the last line of a file that did not end with a newline.
This parser features several improvements over the existing one.
For instance, quoted strings (with escape sequences), unlimited includes,
relaxed newline handling (e.g. at the end of files or before/after { and }),
and the difference between empty and unset values (key = vs. key = "").
It also complains a lot more about invalid syntax. The current one accepts
pretty odd stuff (like settings or sections without name) without any
errors or warnings.
Tobias Brunner