[Python-apps-team] Bug#607112: cython + python3: cimporting an extension type breaks strict aliasing rules

[Jakub Wilk]

Package: cython
Version: 0.13-1
Severity: normal

$ python3 --version
Python 3.1.3
$ cython --verbose ham.pyx
Compiling /tmp/cython-bugs/ham.pyx
$ gcc $(python3-config --cflags) ham.c -shared -o ham.so
ham.c: In function ‘PyInit_ham’:
ham.c:1002: warning: dereferencing pointer ‘vtabptr.99’ does break strict-aliasing rules
ham.c:1002: note: initialized from here


Please note that breaking aliasing rules results in undefined behavior.


-- System Information:
Debian Release: squeeze/sid
    APT prefers unstable
    APT policy: (990, 'unstable'), (500, 'experimental'), (500, 'testing')
Architecture: i386 (x86_64)

Kernel: Linux 2.6.32-5-amd64 (SMP w/2 CPU cores)
Locale: LANG=C, LC_CTYPE=pl_PL.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages cython depends on:
ii  libc6                         2.11.2-7   Embedded GNU C Library: Shared lib
ii  python                        2.6.6-7    interactive high-level object-orie
ii  python-support                1.0.12     automated rebuilding support for P
ii  python2.6                     2.6.6-8    An interactive high-level object-o

cython recommends no packages.

Versions of packages cython suggests:
ii  gcc                           4:4.4.5-2  The GNU C compiler

-- 
Jakub Wilk
-------------- next part --------------
cdef class Eggs:
    cdef int f(self)
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cdef class Eggs:
    cdef int f(self):
        return 42
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from eggs cimport Eggs