Issue #18408: PyEval_EvalFrameEx() and PyEval_CallObjectWithKeywords() now fail
with an assertion error if they are called with an exception set
(PyErr_Occurred()).
If these functions are called with an exception set, the exception may be
cleared and so the caller looses its exception.
Add also assertions to PyEval_CallObjectWithKeywords() and call_function() to
check if the function succeed with no exception set, or the function failed
with an exception set.
diff --git a/Python/ceval.c b/Python/ceval.c
index 2d84c09..8a732a0 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -1203,6 +1203,13 @@
if (throwflag) /* support for generator.throw() */
goto error;
+#ifdef Py_DEBUG
+ /* PyEval_EvalFrameEx() must not be called with an exception set,
+ because it may clear it (directly or indirectly) and so the
+ caller looses its exception */
+ assert(!PyErr_Occurred());
+#endif
+
for (;;) {
#ifdef WITH_TSC
if (inst1 == 0) {
@@ -1223,6 +1230,7 @@
#endif
assert(stack_pointer >= f->f_valuestack); /* else underflow */
assert(STACK_LEVEL() <= co->co_stacksize); /* else overflow */
+ assert(!PyErr_Occurred());
/* Do periodic things. Doing this every time through
the loop would add too much overhead, so we do it
@@ -3125,6 +3133,8 @@
break;
READ_TIMESTAMP(loop1);
+ assert(!PyErr_Occurred());
+
} /* main loop */
assert(why != WHY_YIELD);
@@ -3137,6 +3147,9 @@
if (why != WHY_RETURN)
retval = NULL;
+ assert((retval != NULL && !PyErr_Occurred())
+ || (retval == NULL && PyErr_Occurred()));
+
fast_yield:
if (co->co_flags & CO_GENERATOR && (why == WHY_YIELD || why == WHY_RETURN)) {
/* The purpose of this block is to put aside the generator's exception
@@ -4044,6 +4057,13 @@
{
PyObject *result;
+#ifdef Py_DEBUG
+ /* PyEval_CallObjectWithKeywords() must not be called with an exception
+ set, because it may clear it (directly or indirectly)
+ and so the caller looses its exception */
+ assert(!PyErr_Occurred());
+#endif
+
if (arg == NULL) {
arg = PyTuple_New(0);
if (arg == NULL)
@@ -4066,6 +4086,9 @@
result = PyObject_Call(func, arg, kw);
Py_DECREF(arg);
+
+ assert((result != NULL && !PyErr_Occurred())
+ || (result == NULL && PyErr_Occurred()));
return result;
}
@@ -4228,6 +4251,9 @@
Py_DECREF(w);
PCALL(PCALL_POP);
}
+
+ assert((x != NULL && !PyErr_Occurred())
+ || (x == NULL && PyErr_Occurred()));
return x;
}