Mailman 3 January 2017 - cython-devel

0.25.2b0 with 32bit fixes: (sometimes) Interrupted system call in builtin_subtype_methods_T653
by Yaroslav Halchenko July 6, 2017

July 6, 2017

A fresh one I ran into while rebuilding with fixes for 32bit (thanks BTW! sorry for not prompt followup/gratitude) ====================================================================== ERROR: runTest (__main__.CythonRunTestCase) compiling (cpp) and running builtin_subtype_methods_T653 ---------------------------------------------------------------------- Traceback (most recent call last): File "runtests.py", line 998, in run self.run_tests(result, ext_so_path) File "runtests.py", line 1013, in run_tests self.run_doctests(self.module, result, ext_so_path) File "runtests.py", line 1023, in run_doctests run_forked_test(result, run_test, self.shortDescription(), self.fork) File "runtests.py", line 1076, in run_forked_test cid, result_code = os.waitpid(child_id, 0) OSError: [Errno 4] Interrupted system call ---------------------------------------------------------------------- Ran 581 tests in 188.225s FAILED (errors=1) it is not 100% reproducible. Rebuilding the package went smooth without this hiccup. Just wanted to let you know might be related that the tests were ran as set -e; for P in 2.7 3.5; do \ PYTHONPATH=`/bin/ls -d /build/cython-0.25.2~b0/build/lib.*-$P` \ /usr/bin/python$P runtests.py --shard_count=16 \ --no-refnanny -v -v --exclude="(parallel|Debugger|annotate_html)" --work-dir=build/work-dir 2>&1; \ done so testing in parallel to speed up the build of the package. This one was the only failure I have ran into but it built fine before (but there could have been some changes in the core packages since then) -- Yaroslav O. Halchenko Center for Open Neuroscience http://centerforopenneuroscience.org Dartmouth College, 419 Moore Hall, Hinman Box 6207, Hanover, NH 03755 Phone: +1 (603) 646-9834 Fax: +1 (603) 646-1419 WWW: http://www.linkedin.com/in/yarik

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verify_resolution_GH1533
by Yaroslav Halchenko Jan. 25, 2017

Jan. 25, 2017

Dear Cython gurus, How to skip this test? It is causing failures on i386: https://github.com/cython/cython/issues/1548 and I have tried to skip it, so my test running line now is set -e; for P in 2.7 3.5; do \ PYTHONPATH=`/bin/ls -d /build/cython-0.25.2/build/lib.*-$P` \ /usr/bin/python$P runtests.py --shard_count=16 \ --no-refnanny -v -v --exclude="(parallel|Debugger|annotate_html|numpy_test|verify_resolution_GH1533)" --work-dir=build/work-dir 2>&1; \ done NB numpy_test skip due to https://github.com/cython/cython/issues/1589 but the test still runs and fails: FAIL: verify_resolution_GH1533 (line 90) (cpdef_enums.__test__) Doctest: cpdef_enums.__test__.verify_resolution_GH1533 (line 90) ---------------------------------------------------------------------- Traceback (most recent call last): File "/usr/lib/python2.7/doctest.py", line 2226, in runTest raise self.failureException(self.format_failure(new.getvalue())) AssertionError: Failed doctest test for cpdef_enums.__test__.verify_resolution_GH1533 (line 90) File "/build/cython-0.25.2/build/work-dir/15/run/c/cpdef_enums/cpdef_enums.so", line unknown line number, in verify_resolution_GH1533 (line 90) ---------------------------------------------------------------------- File "/build/cython-0.25.2/build/work-dir/15/run/c/cpdef_enums/cpdef_enums.so", line ?, in cpdef_enums.__test__.verify_resolution_GH1533 (line 90) Failed example: verify_resolution_GH1533() Expected: 3 Got: 3L ---------------------------------------------------------------------- Ran 676 tests in 247.426s FAILED (failures=1) quick reply would be appreciate -- running out of time to upload 0.25.2 into debian for stretch full freeze Cheers -- Yaroslav O. Halchenko Center for Open Neuroscience http://centerforopenneuroscience.org Dartmouth College, 419 Moore Hall, Hinman Box 6207, Hanover, NH 03755 Phone: +1 (603) 646-9834 Fax: +1 (603) 646-1419 WWW: http://www.linkedin.com/in/yarik

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trying to understand why PyString_GET_SIZE cannot be cimport-ed
by Matti Picus Jan. 8, 2017

Jan. 8, 2017

I am working on a branch of PyPy 2.7 to support Pandas (default PyPy is missing some CAPI support that enables the parts of cython used in Pandas). Pandas code has these lines (in lib.pyx) try: from cpython cimport PyString_GET_SIZE except ImportError: from cpython cimport PyUnicode_GET_SIZE as PyString_GET_SIZE For some reason, PyPy fails to cimport PyString_GET_SIZE, but successfully cimports PyUnicode_GET_SIZE. The substitution causes problems for PyPy, I could solve those in a different way, but I would like to understand what is going on. My cython Foo is improving but still too weak to understand why the cimport fails, could someone help me out with a hint? Matti

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Changing the default value of exception propagation
by Robert Bradshaw Jan. 6, 2017

Jan. 6, 2017

By default a cdef (or cpdef) function returning C type suppresses all exceptions, which is quite surprising to new (and old) users, and makes debugging difficult. I would propose that we make exception propagation the default. The primary motivation to not do this would be for fear of performance regression, especially for external functions that can't possibly raise exceptions. While the the catch-all "except *" does seem to have non-trivial overhead, the "except? value" version looks indistinguishable from no exception throwing at all (in tight loops, yay branch prediction, would be interested in what other people see [1]). Does this sound like a reasonable proposal? There are still some open questions, e.g. - What value should we pick. We want something unlikely, but recognizable to external code (e.g. 0xBadBad). - What about non-numeric/pointer/reference types; are there other sentinel values we could use? - Should we default to except * in that case? Presumably these are likely to be more expensive functions anyways (making the relative cost lower). - Or could we use, essentially, reinterpret_cast to get a possible error value? This could work for PODs (including C structs) but destructors could wreck havoc here. - Should we add syntax (e.g. "except -") to manually obtain the old behavior? Or should such be done by surrounding the entire block with an try/bare except statement? This wouldn't catch argument-parsing errors. (Another crazy idea, though I'm not sold, is lifting an initial try and with block that spans the full function body to above the argument parsing--this could simply the gil syntax as well.) - Robert [1] https://gist.github.com/robertwb/0ef6bfaa3c9b2ea11ed64d1c1a0bda43 time_with_nothing 0.0322368144989 3.22368144989e-08 time_with_star 0.097442150116 9.7442150116e-08 time_with_value 0.0940091609955 9.40091609955e-08 time_with_maybe_value 0.10076379776 1.0076379776e-07 time_with_nothing 0.0767869949341 3.8393497467e-08 time_with_star 0.189253091812 9.46265459061e-08 time_with_value 0.176230192184 8.81150960922e-08 time_with_maybe_value 0.179567098618 8.97835493088e-08 time_with_nothing 0.110851049423 3.69503498077e-08 time_with_star 0.268408060074 8.9469353358e-08 time_with_value 0.254024982452 8.46749941508e-08 time_with_maybe_value 0.244876861572 8.16256205241e-08 time_with_nothing 0.138132095337 3.45330238342e-08 time_with_star 0.345059156418 8.62647891045e-08 time_with_value 0.329736948013 8.24342370033e-08 time_with_maybe_value 0.341785907745 8.54464769363e-08 time_with_nothing 0.0680961608887 6.80961608887e-10 time_with_star 0.285541057587 2.85541057587e-09 time_with_value 0.0707340240479 7.07340240479e-10 time_with_maybe_value 0.0762150287628 7.62150287628e-10 time_with_nothing 0.148243904114 7.41219520569e-10 time_with_star 0.560220956802 2.80110478401e-09 time_with_value 0.136430978775 6.82154893875e-10 time_with_maybe_value 0.143126964569 7.15634822845e-10 time_with_nothing 0.211837053299 7.06123510997e-10 time_with_star 0.812189102173 2.70729700724e-09 time_with_value 0.197682142258 6.58940474192e-10 time_with_maybe_value 0.203264951706 6.7754983902e-10 time_with_nothing 0.283420085907 7.08550214767e-10 time_with_star 1.09991884232 2.74979710579e-09 time_with_value 0.281104803085 7.02762007713e-10 time_with_maybe_value 0.288016080856 7.20040202141e-10 DONE

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