Fix remaining Cython/gcc warnings

This fixes all the remaining Cython and gcc warnings when using current Cython master (note, Cython fixed some warnings in recent weeks).

The first commit, cython seems to have a problem when defining multiple 'complex' variables in one line, e.g. ```cdef int a[3], b[3]```. This splits them up into individual lines.

The second commit resolves where because of an assert, some variables are not initialized because they are not used. Still, gcc issues the ```might be used uninitialized in this function``` warning. It fixes it by initializing, even when not used.