Mailman 3 October 2016 - cython-devel

Cython 0.25 released
by Robert Bradshaw Oct. 26, 2016

Oct. 26, 2016

I'm happy to announce the release of Cython 0.25 which has numerous new features and bug fixes. It is available at https://pypi.python.org/pypi/Cython We have also moved bug tracking from trac.cython.org to github issues. However, user support still remains at cython-users@, please refrain from filing issues until you have confirmed an actual bug. - Robert Features added -------------- * def/cpdef methods of cdef classes benefit from Cython's internal function implementation, which enables introspection and line profiling for them. Implementation sponsored by Turbostream (www.turbostream-cfd.com). * The distutils extension ``Cython.Distutils.build_ext`` has now been updated to use cythonize which properly handles dependencies. The old extension can still be found in ``Cython.Distutils.old_build_ext`` and is now deprecated. * Calls to Python functions are faster, following the recent "FastCall" optimisations that Victor Stinner implemented for CPython 3.6. See https://bugs.python.org/issue27128 and related issues. * The new METH_FASTCALL calling convention for PyCFunctions is supported in CPython 3.6. See https://bugs.python.org/issue27810 * C++ classes can now have typedef members. STL containers updated with value_type. * Support for bazel using a the pyx_library rule in //Tools:rules.bzl. * Initial support for using Cython modules in Pyston. Patch by Daetalus. * Dynamic Python attributes are allowed on cdef classes if an attribute ``cdef dict __dict__`` is declared in the class. Patch by empyrical. * Cython implemented C++ classes can make direct calls to base class methods. Patch by empyrical. * New directive ``cython.no_gc`` to fully disable GC for a cdef class. Patch by Claudio Freire. * Buffer variables are no longer excluded from ``locals()``. Patch by da-woods. * Building f-strings is faster, especially when formatting C integers. * for-loop iteration over "std::string". * ``libc/math.pxd`` provides ``e`` and ``pi`` as alias constants to simplify usage as a drop-in replacement for Python's math module. * Speed up cython.inline(). * Binary lshift operations with small constant Python integers are faster. * Some integer operations on Python long objects are faster in Python 2.7. * Support for the C++ ``typeid`` operator. Significant Bugs fixed ---------------------- * Division of complex numbers avoids overflow by using Smith's method. * Some function signatures in ``libc.math`` and ``numpy.pxd`` were incorrect. Patch by Michael Seifert. Other changes ------------- * The "%%cython" IPython/jupyter magic now defaults to the language level of the current jupyter kernel. The language level can be set explicitly with "%%cython -2" or "%%cython -3".

5 6

Cython 0.25 beta
by Robert Bradshaw Oct. 19, 2016

Oct. 19, 2016

Thanks for all of those to tested the alpha release. I think we've managed to fix all the issues and regressions raised in that thread; here's a beta that's likely to turn into a release candidate. https://github.com/cython/cython/archive/0.25b0.zip

4 7

Regression since 0.25a0 involving std::vector
by Jeroen Demeyer Oct. 19, 2016

Oct. 19, 2016

This is a new regression introduced since 0.25a0, found while testing Sage with 0.25b1: from libcpp.vector cimport vector cdef extern from *: cdef cppclass BoostGraph[T]: vector[unsigned long] bandwidth_ordering() ctypedef BoostGraph[int] BoostVecDiGraph Error compiling Cython file: ------------------------------------------------------------ ... from libcpp.vector cimport vector cdef extern from *: cdef cppclass BoostGraph[T]: vector[unsigned long] bandwidth_ordering() ctypedef BoostGraph[int] BoostVecDiGraph ^ ------------------------------------------------------------ /tmp/boost_graph.pyx:5:20: Compiler crash in AnalyseDeclarationsTransform File 'ModuleNode.py', line 118, in analyse_declarations: ModuleNode(boost_graph.pyx:1:0, full_module_name = 'boost_graph') File 'Nodes.py', line 425, in analyse_declarations: StatListNode(boost_graph.pyx:1:0) File 'Nodes.py', line 1567, in analyse_declarations: CTypeDefNode(boost_graph.pyx:5:0, visibility = u'private') File 'Nodes.py', line 1123, in analyse: TemplatedTypeNode(boost_graph.pyx:5:20) Compiler crash traceback from this point on: File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/Nodes.py", line 1123, in analyse self.type = base_type.specialize_here(self.pos, template_types) File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/PyrexTypes.py", line 3462, in specialize_here return self.specialize(dict(zip(self.templates, template_values))) File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/PyrexTypes.py", line 3480, in specialize specialized.scope = self.scope.specialize(values, specialized) File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/Symtab.py", line 2284, in specialize e.type.specialize(values), File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/PyrexTypes.py", line 2746, in specialize result = CFuncType(self.return_type.specialize(values), File "/usr/local/src/sage-config/local/lib/python2.7/site-packages/Cython/Compiler/PyrexTypes.py", line 3489, in specialize T = values[self.templates[0]] KeyError: <CNumericType unsigned long>

2 2