I wanted to re-offer for discussion a fix for a bug I reported a while
back. The code that breaks is this:
import numpy
cimport numpy
def testfunc():
a = numpy.arange(12).reshape([3,4])
cdef numpy.int_t[:,:] a_view = a
cdef numpy.int_t[:,:] b = a_view[:,:].T
One problem is that when a memoryview slice is decremented, the .memview
and .data fields are not set to NULL, and any error that causes a jump
to cleanup code will attempt to decref it again.
The second problem (I think) is that assignment of a transpose of
memoryview slices to a variable is not resulting in an incref on the
underlying slice, even though the variable is not a temporary and
continues to persist.
Here is a patch that solves the problem for me.
https://github.com/SyamGadde/cython/commit/5739d8b908f18c4fc9103ef04e39964d61af3495
The part I am least sure about is removing the "if" qualifications on
the incref and decref:
if self.obj.is_name or self.obj.is_attribute and
self.obj.is_memslice_transpose:
that was obviously there for a reason, but it causes problems in the above
case. If there is a less extreme solution I'd be happy to take it.
Thanks,
-syam
_______________________________________________
cython-devel mailing list
cython-devel@python.org
https://mail.python.org/mailman/listinfo/cython-devel
