carray_from_* unused-function warnings with 0.26b0

Those weren’t present before. We’re building with -Wall because until now the generated code was clean. Here’s an example of failure:

building 'xpra.codecs.csc_swscale.colorspace_converter' extension
creating build/temp.linux-x86_64-2.7/xpra/codecs/csc_swscale
gcc -pthread -fno-strict-aliasing -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -mtune=generic -D_GNU_SOURCE -fPIC -fwrapv -DNDEBUG -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -mtune=generic -D_GNU_SOURCE -fPIC -fwrapv -fPIC -I/usr/include/xpra -I/usr/include/python2.7 -c xpra/codecs/csc_swscale/colorspace_converter.c -o build/temp.linux-x86_64-2.7/xpra/codecs/csc_swscale/colorspace_converter.o -Wl,-rpath,/usr/lib64/xpra -Wall -Werror -fPIC
xpra/codecs/csc_swscale/colorspace_converter.c:12227:12: error: ‘__Pyx_carray_from_py_unsigned_long’ defined but not used [-Werror=unused-function]
 static int __Pyx_carray_from_py_unsigned_long(PyObject *__pyx_v_o, unsigned long *__pyx_v_v, Py_ssize_t __pyx_v_length) {
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
xpra/codecs/csc_swscale/colorspace_converter.c:11690:12: error: ‘__Pyx_carray_from_py_int’ defined but not used [-Werror=unused-function]
 static int __Pyx_carray_from_py_int(PyObject *__pyx_v_o, int *__pyx_v_v, Py_ssize_t __pyx_v_length) {
            ^~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
error: command 'gcc' failed with exit status 1

And:

building 'xpra.codecs.vpx.encoder' extension
creating build/temp.linux-x86_64-2.7/xpra/codecs/vpx
gcc -pthread -fno-strict-aliasing -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -mtune=generic -D_GNU_SOURCE -fPIC -fwrapv -DNDEBUG -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -mtune=generic -D_GNU_SOURCE -fPIC -fwrapv -fPIC -I/usr/include/xpra -I/usr/include/python2.7 -c xpra/codecs/vpx/encoder.c -o build/temp.linux-x86_64-2.7/xpra/codecs/vpx/encoder.o -Wall -Werror -fPIC
xpra/codecs/vpx/encoder.c:21241:30: error: ‘__pyx_convert__to_py_vpx_codec_enc_cfg_t’ defined but not used [-Werror=unused-function]
             static PyObject* __pyx_convert__to_py_vpx_codec_enc_cfg_t(vpx_codec_enc_cfg_t s) {
                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
xpra/codecs/vpx/encoder.c:13358:28: error: ‘__pyx_convert__from_py_vpx_codec_enc_cfg_t’ defined but not used [-Werror=unused-function]
 static vpx_codec_enc_cfg_t __pyx_convert__from_py_vpx_codec_enc_cfg_t(PyObject *__pyx_v_obj) {
                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
error: command 'gcc' failed with exit status 1

Not sure why those functions are generated at all. This problem only affects these two modules out of a well over a dozen. How can I workaround this and get Cython not to generate those functions?

[robertwb]

This should be fixed by 29067ceba6b1370cfd9a9b85a291957c0aaa34a1

[robertwb]

This can be disabled with the auto_pickle directive, e.g. #cython: auto_pickle=False at the top of the file. However, we should be able to test whether conversion is possible without actually generating them, so this bug still should be fixed.