If jextract is ran in "cpp" mode, e.g. using a "compile_flags.txt" file that contains the "-xc++" flag, it fails with non-trivial code because:

* extern C clauses are not recursively scanned
* the first time we see a cursor with language != C, we stop with an exception (instead of skipping)
* typing of enum constant is different in C++ and causes infinite recursion

As a result, jextract is not very usable in combination with "-xc++".