gh-101975: Fixed a potential SegFault on garbage collection (GH-102803)

diff --git a/Misc/NEWS.d/next/Core and Builtins/2023-03-18-02-36-39.gh-issue-101975.HwMR1d.rst b/Misc/NEWS.d/next/Core and Builtins/2023-03-18-02-36-39.gh-issue-101975.HwMR1d.rst
new file mode 100644 (file)
index 0000000..28c9a84
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2023-03-18-02-36-39.gh-issue-101975.HwMR1d.rst
@@ -0,0 +1 @@
+Fixed ``stacktop`` value on tracing entries to avoid corruption on garbage collection.

diff --git a/Python/ceval_macros.h b/Python/ceval_macros.h
index 98b72ec1b364285d86a2d3ce9329b1d2b8033680..c2257515a305994de8a8016d3f1b5761253694c1 100644 (file)
--- a/Python/ceval_macros.h
+++ b/Python/ceval_macros.h
@@ -310,6 +310,7 @@ GETITEM(PyObject *v, Py_ssize_t i) {
         _PyFrame_SetStackPointer(frame, stack_pointer); \
         int err = trace_function_entry(tstate, frame); \
         stack_pointer = _PyFrame_GetStackPointer(frame); \
+        frame->stacktop = -1; \
         if (err) { \
             goto error; \
         } \