The following code compiled just fine with 0.9.4.1 cdef extern from "whatever.h": ctypedef enum someenum_t: ENUMVALUE_1 ENUMVALUE_2 cdef somefunction(someenum_t val): if val == ENUMVALUE_1: print "1" else: print "2" With 0.9.5 it gives the following error: /tmp/Pyrex-0.9.5/regression.pyx:8:11: Invalid types for '==' (someenum_t, someenum_t) anders