merge -r59315:59316 from py3k: Fix issue #1553: An errornous __length_hint__ can make list() raise a SystemError
diff --git a/Misc/NEWS b/Misc/NEWS
index 735b073..24a43f0 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
Core and builtins
-----------------
+- Issue #1553: An errornous __length_hint__ can make list() raise a
+ SystemError.
+
- Issue #1521: On 64bit platforms, using PyArgs_ParseTuple with the t# of w#
format code incorrectly truncated the length to an int, even when
PY_SSIZE_T_CLEAN is set. The str.decode method used to return incorrect
diff --git a/Objects/abstract.c b/Objects/abstract.c
index f7a3bfe..fb123db 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -1507,8 +1507,9 @@
/* Guess result size and allocate space. */
n = _PyObject_LengthHint(v);
if (n < 0) {
- if (!PyErr_ExceptionMatches(PyExc_TypeError) &&
- !PyErr_ExceptionMatches(PyExc_AttributeError)) {
+ if (PyErr_Occurred()
+ && !PyErr_ExceptionMatches(PyExc_TypeError)
+ && !PyErr_ExceptionMatches(PyExc_AttributeError)) {
Py_DECREF(it);
return NULL;
}
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 75ba6d0..c0d0e09 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -784,8 +784,9 @@
/* Guess a result list size. */
n = _PyObject_LengthHint(b);
if (n < 0) {
- if (!PyErr_ExceptionMatches(PyExc_TypeError) &&
- !PyErr_ExceptionMatches(PyExc_AttributeError)) {
+ if (PyErr_Occurred()
+ && !PyErr_ExceptionMatches(PyExc_TypeError)
+ && !PyErr_ExceptionMatches(PyExc_AttributeError)) {
Py_DECREF(it);
return NULL;
}