settrace/setprofile function gets lost

Include/ceval.h

@@ -31,6 +31,7 @@ PyAPI_FUNC(PyObject *) PyEval_CallMethod(PyObject *obj,
 #ifndef Py_LIMITED_API
 PyAPI_FUNC(void) PyEval_SetProfile(Py_tracefunc, PyObject *);
 PyAPI_FUNC(void) PyEval_SetTrace(Py_tracefunc, PyObject *);
+PyAPI_FUNC(void) PyEval_TempResetSetTrace();
 PyAPI_FUNC(void) _PyEval_SetCoroutineOriginTrackingDepth(int new_depth);
 PyAPI_FUNC(int) _PyEval_GetCoroutineOriginTrackingDepth(void);
 PyAPI_FUNC(void) _PyEval_SetCoroutineWrapper(PyObject *);

Lib/test/test_sys_settrace.py

@@ -486,6 +486,7 @@ class RaisingTraceFuncTestCase(unittest.TestCase):
         if event == self.raiseOnEvent:
             raise ValueError # just something that isn't RuntimeError
         else:
+            print(1)
             return self.trace
 
     def f(self):

Python/ceval.c

@@ -4589,6 +4589,18 @@ PyEval_SetTrace(Py_tracefunc func, PyObject *arg)
                            || (tstate->c_profilefunc != NULL));
 }
 
+void
+PyEval_TempResetSetTrace()
+{
+    _PyRuntimeState *runtime = &_PyRuntime;
+    PyThreadState *tstate = _PyRuntimeState_GetThreadState(runtime);
+    Py_tracefunc tracefunc = tstate->c_tracefunc;
+    PyObject *traceobj = tstate->c_traceobj;
+    Py_XINCREF(traceobj);
+    PyEval_SetTrace(NULL, NULL);
+    PyEval_SetTrace(tracefunc, traceobj);
+}
+
 void
 _PyEval_SetCoroutineOriginTrackingDepth(int new_depth)
 {

Python/sysmodule.c

@@ -558,7 +558,7 @@ trace_trampoline(PyObject *self, PyFrameObject *frame,
         return 0;
     result = call_trampoline(callback, frame, what, arg);
     if (result == NULL) {
-        PyEval_SetTrace(NULL, NULL);
+        PyEval_TempResetSetTrace();
         Py_CLEAR(frame->f_trace);
         return -1;
     }