1 files changed, 3 insertions, 0 deletions
diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index d48fb17..af430fb 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -1397,6 +1397,9 @@ varname_converter(PyObject *in, void *_out)
     if (PyUnicode_Check(in)) {
         Py_ssize_t size;
         s = PyUnicode_AsUTF8AndSize(in, &size);
+        if (s == NULL) {
+            return 0;
+        }
         if (size > INT_MAX) {
             PyErr_SetString(PyExc_OverflowError, "string is too long");
             return 0;