[Cython] rev 809 - cdef exception propagation

[Stefan Behnel]

Hi,

revision 809 implements a nice feature which lets cdef functions propagate
exceptions by default. However, the change also introduced a problem with
nogil functions, when called without the GIL being held. I added a
run/nogil.pyx test case for now which crashes for me.

Looking through the change I get the impression that the signature
modification is done too late in the processing. To me, it feels more like
this should be something that should be handled at the tree level and
reflected directly in the function signature. What do you think?

Stefan