diff --git a/Objects/abstract.c b/Objects/abstract.c
index 2f887aa..11e145f 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -331,7 +331,7 @@
 {
     if (!PyObject_CheckBuffer(obj)) {
         PyErr_Format(PyExc_TypeError,
-                     "'%100s' does not support the buffer interface",
+                     "'%.100s' does not support the buffer interface",
                      Py_TYPE(obj)->tp_name);
         return -1;
     }
diff --git a/Python/ceval.c b/Python/ceval.c
index d2444aa..50d5aac 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -4130,7 +4130,7 @@
                 if (PyErr_ExceptionMatches(PyExc_TypeError)) {
                     PyErr_Format(PyExc_TypeError,
                                  "%.200s%.200s argument after * "
-                                 "must be a sequence, not %200s",
+                                 "must be a sequence, not %.200s",
                                  PyEval_GetFuncName(func),
                                  PyEval_GetFuncDesc(func),
                                  stararg->ob_type->tp_name);