Compile error: using cpdef enum and typedef enum

I observed a compilation error from clang-800.0.38 on a MacBook when using a c enum and a Cython cpdef enum. I could reproduce the issue using gcc version 4.9.2 (Raspbian 4.9.2-10). In both cases, Cython version 0.25.1 was used.

The code I ran was:

#lib.h
typedef enum { A, B, C, D} foo;

#lib.pyx
cdef extern from "./lib.h":
    cpdef enum foo:
        A, B, C, D

def t1():
    for e in foo: print(e.name)

When trying to compile, clang throws a lot of errors which all seem to correlate with the “enum foo”. A solution is to declare the enum in the .h file as following typedef enum foo { A, B, C, D} foo;or as typedef enum foo { A, B, C, D};. When changed, the code is compiled and linked to a .so file and is working as intended.

Is this intended behaviour or bug?

[embray]

+1 for some kind of “cptypedef”. Kinda ugly but I don’t see a better way…

[llchan]

Is cptypedef something that we can add?

My current workaround is rather verbose, especially when there are a lot of enums values. It looks something like this:

cdef extern from './lib.h':
    ctypedef enum _foo 'foo':
        _A 'A'
        _B 'B'
        _C 'C'
        _D 'D'

cpdef enum foo:
    A = _A
    B = _B
    C = _C
    D = _D

My actual code is even more verbose because I prefix the ctypedef enum names so they don’t pollute the global namespace.