PIPER-ALPHA:language_level[language_level_3]$ ./rebuild
+++ dirname ./rebuild
++ cd .
++ pwd
+ : /tmp/language_level
++ dirname /tmp/language_level
+ : /tmp
+ rm -rf /tmp/language_level/build
+ rm -rf /tmp/language_level/mypackage/__pycache__/
+ rm -f /tmp/language_level/mypackage/mycymod.cpp
+ rm -f /tmp/language_level/mypackage/mycymod.cpython-37m-darwin.so
+ python /tmp/language_level/setup.py build_ext --inplace
WARNING  Pythran support disabled for module: omp
import: module numpy found
Warning: passing language='c++' to cythonize() is deprecated. Instead, put "# distutils: language=c++" in your .pyx or .pxd file(s)
Compiling mypackage/mycymod.pyx because it changed.
[1/1] Cythonizing mypackage/mycymod.pyx

Error compiling Cython file:
------------------------------------------------------------
...
cimport cython

from libc.stdint cimport *
from libcpp.string cimport string

from ext.halide.mycppwrappers cimport Outputs as HalOutputs
^
------------------------------------------------------------

mypackage/mycymod.pyx:11:0: 'ext/halide/mycppwrappers.pxd' not found

Error compiling Cython file:
------------------------------------------------------------
...
cimport cython

from libc.stdint cimport *
from libcpp.string cimport string

from ext.halide.mycppwrappers cimport Outputs as HalOutputs
^
------------------------------------------------------------

mypackage/mycymod.pyx:11:0: 'ext/halide/mycppwrappers/Outputs.pxd' not found

Error compiling Cython file:
------------------------------------------------------------
...
@cython.freelist(32)
cdef class Outputs:
    """ Cython wrapper class for Halide::Outputs """

    cdef:
        HalOutputs __this__
       ^
------------------------------------------------------------

mypackage/mycymod.pyx:76:8: 'HalOutputs' is not a type identifier
Traceback (most recent call last):
  File "/tmp/language_level/setup.py", line 98, in <module>
    embedsignature=True)
  File "/usr/local/lib/python3.7/site-packages/Cython/Build/Dependencies.py", line 1086, in cythonize
    cythonize_one(*args)
  File "/usr/local/lib/python3.7/site-packages/Cython/Build/Dependencies.py", line 1209, in cythonize_one
    raise CompileError(None, pyx_file)
Cython.Compiler.Errors.CompileError: mypackage/mycymod.pyx
+ set +x
PIPER-ALPHA:language_level[language_level_3 •]$