Skip to content

bpo-22273: Changed conditions for ctypes array-in-struct handling. #16381

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
vsajip merged 1 commit into from
Sep 25, 2019
Merged

bpo-22273: Changed conditions for ctypes array-in-struct handling. #16381

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion Lib/ctypes/test/test_structures.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -480,7 +480,7 @@ class X(Structure):
self.assertEqual(s.first, got.first)
self.assertEqual(s.second, got.second)

@unittest.skipIf(MACHINE in ('armv7l', 'ppc64'),
@unittest.skipIf(MACHINE.startswith(('arm', 'ppc')),
'Test temporarily disabled on this architecture')
def test_array_in_struct(self):
# See bpo-22273
Expand Down
11 changes: 4 additions & 7 deletions Modules/_ctypes/stgdict.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -350,9 +350,7 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
int pack;
Py_ssize_t ffi_ofs;
int big_endian;
#if defined(X86_64)
int arrays_seen = 0;
#endif

/* HACK Alert: I cannot be bothered to fix ctypes.com, so there has to
be a way to use the old, broken semantics: _fields_ are not extended
Expand Down Expand Up @@ -504,10 +502,8 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
Py_XDECREF(pair);
return -1;
}
#if defined(X86_64)
if (PyCArrayTypeObject_Check(desc))
arrays_seen = 1;
#endif
dict = PyType_stgdict(desc);
if (dict == NULL) {
Py_DECREF(pair);
Expand Down Expand Up @@ -648,8 +644,6 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
stgdict->align = total_align;
stgdict->length = len; /* ADD ffi_ofs? */

#if defined(X86_64)

#define MAX_ELEMENTS 16

if (arrays_seen && (size <= MAX_ELEMENTS)) {
Expand All @@ -669,6 +663,10 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
* accurate set, to allow libffi to marshal them into registers
* correctly. It means one more loop over the fields, but if we got
* here, the structure is small, so there aren't too many of those.
*
* Although the passing in registers is specific to 64-bit Linux, the
* array-in-struct vs. pointer problem is general. But we restrict the
* type transformation to small structs nonetheless.
*/
ffi_type *actual_types[MAX_ELEMENTS + 1];
int actual_type_index = 0;
Expand Down Expand Up @@ -746,7 +744,6 @@ PyCStructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct
memcpy(&stgdict->ffi_type_pointer.elements[ffi_ofs], actual_types,
actual_type_index * sizeof(ffi_type *));
}
#endif

/* We did check that this flag was NOT set above, it must not
have been set until now. */
Expand Down