1 files changed, 3 insertions, 1 deletions
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
index a2fc0a4..b511e4c 100644
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -397,7 +397,9 @@ frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno, void *Py_UNUSED(ignore
         return -1;
     }
 
-    int len = PyBytes_GET_SIZE(f->f_code->co_code)/sizeof(_Py_CODEUNIT);
+    /* PyCode_NewWithPosOnlyArgs limits co_code to be under INT_MAX so this
+     * should never overflow. */
+    int len = (int)(PyBytes_GET_SIZE(f->f_code->co_code) / sizeof(_Py_CODEUNIT));
     int *lines = marklines(f->f_code, len);
     if (lines == NULL) {
         return -1;