refactor: don't access frame structs directly

They've been moved behind APIs since 3.10 and 3.11, but 3.13 forced our hand.

coverage/ctracer/tracer.c

@@ -508,15 +508,14 @@ CTracer_handle_call(CTracer *self, PyFrameObject *frame)
         Py_XDECREF(self->pcur_entry->file_data);
         self->pcur_entry->file_data = NULL;
         self->pcur_entry->file_tracer = Py_None;
-        frame->f_trace_lines = 0;
+        MyFrame_NoTraceLines(frame);
         SHOWLOG(PyFrame_GetLineNumber(frame), filename, "skipped");
     }
 
     self->pcur_entry->disposition = disposition;
 
     /* Make the frame right in case settrace(gettrace()) happens. */
-    Py_INCREF(self);
-    Py_XSETREF(frame->f_trace, (PyObject*)self);
+    MyFrame_SetTrace(frame, self);
 
     /* A call event is really a "start frame" event, and can happen for
      * re-entering a generator also.  How we tell the difference depends on

coverage/ctracer/util.h

@@ -16,7 +16,10 @@
 // 3.11 moved f_lasti into an internal structure. This is totally the wrong way
 // to make this work, but it's all I've got until https://bugs.python.org/issue40421
 // is resolved.
+#if PY_VERSION_HEX < 0x030D0000
 #include <internal/pycore_frame.h>
+#endif
+
 #if PY_VERSION_HEX >= 0x030B00A7
 #define MyFrame_GetLasti(f)     (PyFrame_GetLasti(f))
 #else
@@ -30,6 +33,14 @@
 #define MyFrame_GetLasti(f)     ((f)->f_lasti)
 #endif
 
+#if PY_VERSION_HEX >= 0x030D0000
+#define MyFrame_NoTraceLines(f) (PyObject_SetAttrString((PyObject*)(f), "f_trace_lines", Py_False))
+#define MyFrame_SetTrace(f, obj)    (PyObject_SetAttrString((PyObject*)(f), "f_trace", (PyObject*)(obj)))
+#else
+#define MyFrame_NoTraceLines(f) ((f)->f_trace_lines = 0)
+#define MyFrame_SetTrace(f, obj)    {Py_INCREF(obj); Py_XSETREF((f)->f_trace, (PyObject*)(obj));}
+#endif
+
 // Access f_code should be done through a helper starting in 3.9.
 #if PY_VERSION_HEX >= 0x03090000
 #define MyFrame_GetCode(f)      (PyFrame_GetCode(f))