diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index bb1cc83..f1968e2 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -1109,7 +1109,7 @@
 unicode_encodedecimal(PyObject *self, PyObject *args)
 {
     Py_UNICODE *unicode;
-    Py_ssize_t length;
+    int length;
     char *errors = NULL;
     PyObject *decimal;
     Py_ssize_t decimal_length, new_length;