[Numpy-discussion] PATCH: reference leaks for 'numpy.core._internal' module object

[Lisandro Dalcin]

The simple test below show the issue.

import sys
import numpy as np
from numpy.core import _internal

def f(a = np.zeros(4)):
    a = np.zeros(4)
    b = memoryview(a)
    c = np.asarray(b)
    print sys.getrefcount(_internal)

while 1:
    f()

The patch it trivial (I've added a little extra, unrelated NULL check):

Index: numpy/core/src/multiarray/buffer.c
===================================================================
--- numpy/core/src/multiarray/buffer.c	(revision 8468)
+++ numpy/core/src/multiarray/buffer.c	(working copy)
@@ -747,9 +747,13 @@
     }
     str = PyUString_FromStringAndSize(buf, strlen(buf));
     free(buf);
+    if (str == NULL) {
+        return NULL;
+    }
     descr = (PyArray_Descr*)PyObject_CallMethod(
         _numpy_internal, "_dtype_from_pep3118", "O", str);
     Py_DECREF(str);
+    Py_DECREF(_numpy_internal);
     if (descr == NULL) {
         PyErr_Format(PyExc_ValueError,
                      "'%s' is not a valid PEP 3118 buffer format string", buf);


PS: I think that such implementation should at least handle the very
simple one/two character format (eg, 'i', 'f', 'd', 'Zf', 'Zd', etc.)
without calling Python code... Of course, complaints without patches
should not be taken too seriously ;-)


-- 
Lisandro Dalcin
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