Fix segfault caused by NULL suboffsets

Cython/Compiler/MemoryView.py

@@ -471,15 +471,19 @@ def assign_scalar(dst, scalar, code):
         code.putln("%s __pyx_temp_slice = %s;" % (slice_decl, dst.result()))
         dst_temp = "__pyx_temp_slice"
 
-    with slice_iter(dst.type, dst_temp, dst.type.ndim, code) as p:
-        if dtype.is_pyobject:
-            code.putln("Py_DECREF((PyObject *) %s);" % p)
+    # with slice_iter(dst.type, dst_temp, dst.type.ndim, code) as p:
+    slice_iter_obj = slice_iter(dst.type, dst_temp, dst.type.ndim, code)
+    p = slice_iter_obj.start_loops()
 
-        code.putln("*((%s *) %s) = __pyx_temp_scalar;" % (type_decl, p))
+    if dtype.is_pyobject:
+        code.putln("Py_DECREF((PyObject *) %s);" % p)
 
-        if dtype.is_pyobject:
-            code.putln("Py_INCREF(__pyx_temp_scalar);")
+    code.putln("*((%s *) %s) = __pyx_temp_scalar;" % (type_decl, p))
 
+    if dtype.is_pyobject:
+        code.putln("Py_INCREF(__pyx_temp_scalar);")
+
+    slice_iter_obj.end_loops()
     code.end_block()
 
 def slice_iter(slice_type, slice_temp, ndim, code):
@@ -496,7 +500,7 @@ class SliceIter(object):
         self.ndim = ndim
 
 class ContigSliceIter(SliceIter):
-    def __enter__(self):
+    def start_loops(self):
         code = self.code
         code.begin_block()
 
@@ -514,13 +518,13 @@ class ContigSliceIter(SliceIter):
 
         return "__pyx_temp_pointer"
 
-    def __exit__(self, *args):
+    def end_loops(self):
         self.code.putln("__pyx_temp_pointer += 1;")
         self.code.putln("}")
         self.code.end_block()
 
 class StridedSliceIter(SliceIter):
-    def __enter__(self):
+    def start_loops(self):
         code = self.code
         code.begin_block()
 
@@ -543,7 +547,7 @@ class StridedSliceIter(SliceIter):
 
         return "__pyx_temp_pointer_%d" % (self.ndim - 1)
 
-    def __exit__(self, *args):
+    def end_loops(self):
         code = self.code
         for i in range(self.ndim - 1, -1, -1):
             code.putln("__pyx_temp_pointer_%d += __pyx_temp_stride_%d;" % (i, i))

Cython/Utility/MemoryView.pyx

@@ -403,7 +403,8 @@ cdef class memoryview(object):
 
         # It would be easy to support indirect dimensions, but it's easier
         # to disallow :)
-        assert_direct_dimensions(self.view.suboffsets, self.view.ndim)
+        if self.view.suboffsets != NULL:
+            assert_direct_dimensions(self.view.suboffsets, self.view.ndim)
         slice_assign_scalar(dst_slice, self.view.ndim, self.view.itemsize,
                             item, self.dtype_is_object)
         free(tmp)
@@ -973,14 +974,22 @@ cdef {{memviewslice_name}} *get_slice_from_memview(memoryview memview,
 @cname('__pyx_memoryview_slice_copy')
 cdef void slice_copy(memoryview memview, {{memviewslice_name}} *dst):
     cdef int dim
+    cdef Py_ssize_t *shape, *strides, *suboffsets
+
+    shape = memview.view.shape
+    strides = memview.view.strides
+    suboffsets = memview.view.suboffsets
 
     dst.memview = <__pyx_memoryview *> memview
     dst.data = <char *> memview.view.buf
 
     for dim in range(memview.view.ndim):
-        dst.shape[dim] = memview.view.shape[dim]
-        dst.strides[dim] = memview.view.strides[dim]
-        dst.suboffsets[dim] = memview.view.suboffsets[dim]
+        dst.shape[dim] = shape[dim]
+        dst.strides[dim] = strides[dim]
+        if suboffsets == NULL:
+            dst.suboffsets[dim] = -1
+        else:
+            dst.suboffsets[dim] = suboffsets[dim]
 
 @cname('__pyx_memoryview_copy_object')
 cdef memoryview_copy(memoryview memview):

tests/run/numpy_memoryview.pyx

@@ -189,20 +189,23 @@ def test_transpose():
 
     print a[3, 2], a.T[2, 3], a_obj[3, 2], a_obj.T[2, 3], numpy_obj[3, 2], numpy_obj.T[2, 3]
 
-@testcase
+@testcase_numpy_1_5
 def test_numpy_like_attributes(cyarray):
     """
+    For some reason this fails in numpy 1.4, with shape () and strides (40, 8)
+    instead of 20, 4 on my machine. Investigate this.
+
     >>> cyarray = create_array(shape=(8, 5), mode="c")
     >>> test_numpy_like_attributes(cyarray)
     >>> test_numpy_like_attributes(cyarray.memview)
     """
     numarray = np.asarray(cyarray)
 
-    assert cyarray.shape == numarray.shape
-    assert cyarray.strides == numarray.strides
-    assert cyarray.ndim == numarray.ndim
-    assert cyarray.size == numarray.size
-    assert cyarray.nbytes == numarray.nbytes
+    assert cyarray.shape == numarray.shape, (cyarray.shape, numarray.shape)
+    assert cyarray.strides == numarray.strides, (cyarray.strides, numarray.strides)
+    assert cyarray.ndim == numarray.ndim, (cyarray.ndim, numarray.ndim)
+    assert cyarray.size == numarray.size, (cyarray.size, numarray.size)
+    assert cyarray.nbytes == numarray.nbytes, (cyarray.nbytes, numarray.nbytes)
 
     cdef int[:, :] mslice = numarray
     assert (<object> mslice).base is numarray