I think that there is a problem with cffi pyopencl was built with python3-cffi-backend i386 1.11.5-1 [80.2 kB] but the backend used for the test is the current 1.11.5-3. here the Debian changelog python-cffi (1.11.5-3) unstable; urgency=medium [ Ondřej Nový ] * Use 'python3 -m sphinx' instead of sphinx-build for building docs [ Stefano Rivera ] * Patch skip-double-float-int: Skip big double->float inf tests on ppc64el, they are known to fail on gcc8, and the blame is being debated upstream. * Patch skip-init-locking-hurd: Skip a non-critical test that fails occasionally Hurd. (See: #893743) * Bump Standards-Version to 4.2.1, no changes needed. -- Stefano Rivera <stefa...@debian.org> Wed, 12 Sep 2018 17:05:03 +0300 python-cffi (1.11.5-2) unstable; urgency=medium [ Ondřej Nový ] * d/tests: Use AUTOPKGTEST_TMP instead of ADTTMP * d/control: Remove ancient X-Python-Version field * d/control: Remove ancient X-Python3-Version field [ Stefano Rivera ] * Add python-cffi-doc package with Sphinx docs (Closes: #891865) * Patch: x32-pointers: handle pointers on ILP32 ABIs correctly. (Closes: #884705) * Bump Standards-Version to 4.2.0, no changes needed.