Explicitly ignore an error return value since we're resetting the exception state afterwards.

Cython/Utility/Exceptions.c

@@ -681,7 +681,8 @@ static int __Pyx_CLineForTraceback(CYTHON_NCP_UNUSED PyThreadState *tstate, int
     }
     if (!use_cline) {
         c_line = 0;
-        PyObject_SetAttr(${cython_runtime_cname}, PYIDENT("cline_in_traceback"), Py_False);
+        // No need to handle errors here when we reset the exception state just afterwards.
+        (void) PyObject_SetAttr(${cython_runtime_cname}, PYIDENT("cline_in_traceback"), Py_False);
     }
     else if (use_cline == Py_False || (use_cline != Py_True && PyObject_Not(use_cline) != 0)) {
         c_line = 0;