Python 3.4 & undefined reference to `_PyGen_Send'

[KeyWeeUsr]

• GCC from mingwpy-0.1.0b3
• Python 3.4.4
• Cython 0.27.2

I think it was introduced in 0.27, our build reports the issue for Python 3.4 versions. See this commit - 72acc2c and

cython/Cython/Utility/Coroutine.c

Line 787 in 94acc16

// _PyGen_Send() is not exported before Py3.6

Also notice 3.3+ referenced here and not in the rest of the lines:

cython/Cython/Utility/Coroutine.c

Line 786 in 94acc16

#if CYTHON_COMPILING_IN_CPYTHON && PY_VERSION_HEX >= 0x03030000 && (!defined(_MSC_VER) || PY_VERSION_HEX >= 0x03060000)

build ↓

writing build\temp.win32-3.4\Release\kivy\_event.def
C:\Python34\Scripts\gcc.exe -shared -s build\temp.win32-3.4\Release\kivy\_event.o build\temp.win32-3.4\Release\kivy\_event.def -LC:\Python34\libs -LC:\Python34\libs -LC:\Python34\PCbuild -lpython34 -lmsvcr100 -o C:\projects\kivy\kivy\_event.pyd -lm
build
\temp.win32-3.4\Release\kivy\_event.o:_event.c:(.text+0x45da): undefined reference to `_PyGen_Send'
build\temp.win32-3.4\Release\kivy\_event.o:_event.c:(.text+0x9290): undefined reference to `_PyGen_Send
'
collect2.exe: error: ld returned 1 exit status
 error: command 'C:\\Python34\\Scripts\\gcc.exe' failed with exit status 1
Failed with exit code 1

The file _event.pxd hasn't changed for quite a while + the build worked fine with <0.27.

Any ideas how to fix it without downgrading to 0.26?

[scoder]

MinGW probably doesn't set _MSC_VER (because, why should it?), so the guard doesn't apply and opens up the special case for Python < 3.6. Problem is, it shouldn't guard against MSVC since this is a platform issue, not a compiler thing. The _PyGen_Send() function is not properly exported before python/cpython@833c626, and the fact that Linux systems do not care is not a good excuse for blaming it on Windows (let alone MSVC, although that is always a good target for blaming). I'll change the guard to defined(__linux__) for 0.27.3.

[KeyWeeUsr]

@scoder Thanks for such a quick response and for the fix! :) Any ETA for 0.27.3?