Issue 3611: in some cases (a __del__ re-raising an exception, when called from inside
an 'except' clause), the exception __context__ would be reset to None.
This crases the interpreter if this precisely happens inside PyErr_SetObject.
- now the __context__ is properly preserved
- in any case, PyErr_SetObject now saves the current exc_value in a local variable, to
avoid such crashes in the future.
Reviewer: Antoine Pitrou.
diff --git a/Python/errors.c b/Python/errors.c
index d7aac6d..6335388 100644
--- a/Python/errors.c
+++ b/Python/errors.c
@@ -53,6 +53,7 @@
PyErr_SetObject(PyObject *exception, PyObject *value)
{
PyThreadState *tstate = PyThreadState_GET();
+ PyObject *exc_value;
PyObject *tb = NULL;
if (exception != NULL &&
@@ -63,8 +64,10 @@
return;
}
Py_XINCREF(value);
- if (tstate->exc_value != NULL && tstate->exc_value != Py_None) {
+ exc_value = tstate->exc_value;
+ if (exc_value != NULL && exc_value != Py_None) {
/* Implicit exception chaining */
+ Py_INCREF(exc_value);
if (value == NULL || !PyExceptionInstance_Check(value)) {
/* We must normalize the value right now */
PyObject *args, *fixed_value;
@@ -88,8 +91,8 @@
This is O(chain length) but context chains are
usually very short. Sensitive readers may try
to inline the call to PyException_GetContext. */
- if (tstate->exc_value != value) {
- PyObject *o = tstate->exc_value, *context;
+ if (exc_value != value) {
+ PyObject *o = exc_value, *context;
while ((context = PyException_GetContext(o))) {
Py_DECREF(context);
if (context == value) {
@@ -98,8 +101,9 @@
}
o = context;
}
- Py_INCREF(tstate->exc_value);
- PyException_SetContext(value, tstate->exc_value);
+ PyException_SetContext(value, exc_value);
+ } else {
+ Py_DECREF(exc_value);
}
}
if (value != NULL && PyExceptionInstance_Check(value))