diff --git a/Modules/_io/stringio.c b/Modules/_io/stringio.c
index c40163f4def..a4536b1b07c 100644
--- a/Modules/_io/stringio.c
+++ b/Modules/_io/stringio.c
@@ -131,6 +131,10 @@ write_str(stringio *self, PyObject *obj)
         return -1;
 
     assert(PyUnicode_Check(decoded));
+    if (PyUnicode_READY(decoded)) {
+        Py_DECREF(decoded);
+        return -1;
+    }
     len = PyUnicode_GET_LENGTH(decoded);
 
     assert(len >= 0);
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index a958951c896..cd67f60906b 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -2120,6 +2120,10 @@ PyUnicode_FromFormatV(const char *format, va_list vargs)
                     str_obj = PyUnicode_DecodeUTF8(str, strlen(str), "replace");
                     if (!str_obj)
                         goto fail;
+                    if (PyUnicode_READY(str_obj)) {
+                        Py_DECREF(str_obj);
+                        goto fail;
+                    }
                     argmaxchar = PyUnicode_MAX_CHAR_VALUE(str_obj);
                     maxchar = Py_MAX(maxchar, argmaxchar);
                     n += PyUnicode_GET_LENGTH(str_obj);
@@ -2625,10 +2629,12 @@ PyUnicode_Decode(const char *s,
         goto onError;
     }
     Py_DECREF(buffer);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&unicode)) {
         Py_DECREF(unicode);
         return NULL;
     }
+#endif
     return unicode;
 
   onError:
@@ -3674,10 +3680,12 @@ utf7Error:
 
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&unicode)) {
         Py_DECREF(unicode);
         return NULL;
     }
+#endif
     return (PyObject *)unicode;
 
   onError:
@@ -4244,10 +4252,12 @@ PyUnicode_DecodeUTF8Stateful(const char *s,
 
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&unicode)) {
         Py_DECREF(unicode);
         return NULL;
     }
+#endif
     return (PyObject *)unicode;
 
   onError:
@@ -4747,10 +4757,12 @@ PyUnicode_DecodeUTF32Stateful(const char *s,
 
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&unicode)) {
         Py_DECREF(unicode);
         return NULL;
     }
+#endif
     return (PyObject *)unicode;
 
   onError:
@@ -5145,10 +5157,12 @@ PyUnicode_DecodeUTF16Stateful(const char *s,
 
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&unicode)) {
         Py_DECREF(unicode);
         return NULL;
     }
+#endif
     return (PyObject *)unicode;
 
   onError:
@@ -5604,10 +5618,12 @@ PyUnicode_DecodeUnicodeEscape(const char *s,
     }
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 
   ucnhashError:
@@ -5905,10 +5921,12 @@ PyUnicode_DecodeRawUnicodeEscape(const char *s,
         goto onError;
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 
   onError:
@@ -6093,10 +6111,12 @@ _PyUnicode_DecodeUnicodeInternal(const char *s,
         goto onError;
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 
   onError:
@@ -6519,10 +6539,12 @@ PyUnicode_DecodeASCII(const char *s,
             goto onError;
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 
   onError:
@@ -6713,10 +6735,12 @@ PyUnicode_DecodeMBCSStateful(const char *s,
         goto retry;
     }
 #endif
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 }
 
@@ -7012,10 +7036,12 @@ PyUnicode_DecodeCharmap(const char *s,
             goto onError;
     Py_XDECREF(errorHandler);
     Py_XDECREF(exc);
+#ifndef DONT_MAKE_RESULT_READY
     if (_PyUnicode_READY_REPLACE(&v)) {
         Py_DECREF(v);
         return NULL;
     }
+#endif
     return (PyObject *)v;
 
   onError:
@@ -8057,10 +8083,12 @@ PyUnicode_TransformDecimalToASCII(Py_UNICODE *s,
                 p[i] = '0' + decimal;
         }
     }
-    if (PyUnicode_READY((PyUnicodeObject*)result) == -1) {
+#ifndef DONT_MAKE_RESULT_READY
+    if (_PyUnicode_READY_REPLACE(&result)) {
         Py_DECREF(result);
         return NULL;
     }
+#endif
     return result;
 }
 /* --- Decimal Encoder ---------------------------------------------------- */
@@ -10038,17 +10066,17 @@ PyUnicode_Append(PyObject **p_left, PyObject *right)
         goto error;
     }
 
+    if (PyUnicode_READY(left))
+        goto error;
+    if (PyUnicode_READY(right))
+        goto error;
+
     if (PyUnicode_CheckExact(left) && left != unicode_empty
         && PyUnicode_CheckExact(right) && right != unicode_empty
         && unicode_resizable(left)
         && (_PyUnicode_KIND(right) <= _PyUnicode_KIND(left)
             || _PyUnicode_WSTR(left) != NULL))
     {
-        if (PyUnicode_READY(left))
-            goto error;
-        if (PyUnicode_READY(right))
-            goto error;
-
         /* Don't resize for ascii += latin1. Convert ascii to latin1 requires
            to change the structure size, but characters are stored just after
            the structure, and so it requires to move all charactres which is
@@ -10265,10 +10293,12 @@ unicode_expandtabs(PyUnicodeObject *self, PyObject *args)
         }
     }
     assert (j == PyUnicode_GET_LENGTH(u));
-    if (PyUnicode_READY(u)) {
+#ifndef DONT_MAKE_RESULT_READY
+    if (_PyUnicode_READY_REPLACE(&u)) {
         Py_DECREF(u);
         return NULL;
     }
+#endif
     return (PyObject*) u;
 
   overflow:
@@ -12923,7 +12953,7 @@ unicode_subtype_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
     if (unicode == NULL)
         return NULL;
     assert(_PyUnicode_CHECK(unicode));
-    if (_PyUnicode_READY_REPLACE(&unicode))
+    if (PyUnicode_READY(unicode))
         return NULL;
 
     self = (PyUnicodeObject *) type->tp_alloc(type, 0);
@@ -13131,7 +13161,7 @@ PyUnicode_InternInPlace(PyObject **p)
     if (PyUnicode_CHECK_INTERNED(s))
         return;
     if (_PyUnicode_READY_REPLACE(p)) {
-        assert(0 && "PyUnicode_READY fail in PyUnicode_InternInPlace");
+        assert(0 && "_PyUnicode_READY_REPLACE fail in PyUnicode_InternInPlace");
         return;
     }
     s = (PyUnicodeObject *)(*p);
@@ -13217,8 +13247,10 @@ _Py_ReleaseInternedUnicodeStrings(void)
             n);
     for (i = 0; i < n; i++) {
         s = (PyUnicodeObject *) PyList_GET_ITEM(keys, i);
-        if (PyUnicode_READY(s) == -1)
+        if (PyUnicode_READY(s) == -1) {
+            assert(0 && "could not ready string");
             fprintf(stderr, "could not ready string\n");
+        }
         switch (PyUnicode_CHECK_INTERNED(s)) {
         case SSTATE_NOT_INTERNED:
             /* XXX Shouldn't happen */
diff --git a/Python/getargs.c b/Python/getargs.c
index 0e7d9c43506..2c2db36193c 100644
--- a/Python/getargs.c
+++ b/Python/getargs.c
@@ -834,14 +834,21 @@ convertsimple(PyObject *arg, const char **p_format, va_list *p_va, int flags,
 
     case 'C': {/* unicode char */
         int *p = va_arg(*p_va, int *);
-        if (PyUnicode_Check(arg) &&
-            PyUnicode_GET_LENGTH(arg) == 1) {
-            int kind = PyUnicode_KIND(arg);
-            void *data = PyUnicode_DATA(arg);
-            *p = PyUnicode_READ(kind, data, 0);
-        }
-        else
+        int kind;
+        void *data;
+
+        if (!PyUnicode_Check(arg))
             return converterr("a unicode character", arg, msgbuf, bufsize);
+
+        if (PyUnicode_READY(arg))
+            RETURN_ERR_OCCURRED;
+
+        if (PyUnicode_GET_LENGTH(arg) != 1)
+            return converterr("a unicode character", arg, msgbuf, bufsize);
+
+        kind = PyUnicode_KIND(arg);
+        data = PyUnicode_DATA(arg);
+        *p = PyUnicode_READ(kind, data, 0);
         break;
     }