We should maintain the invariant that a zero `ob_tid` implies the refcount fields are merged. * Move the assignment in `_Py_MergeZeroLocalRefcount` to immediately before the refcount merge. * Update `_PyTrash_thread_destroy_chain` to set `ob_ref_shared` to `_Py_REF_MERGED` when setting `ob_tid` to zero. Also check this invariant with assertions in the GC in debug builds. That uncovered a bug when running out of memory during GC.
55 KiB
55 KiB