diff -r ac93d188ebd6 Doc/c-api/unicode.rst
--- a/Doc/c-api/unicode.rst	Tue Nov 15 09:12:36 2016 +0100
+++ b/Doc/c-api/unicode.rst	Tue Nov 15 21:20:16 2016 +0200
@@ -1643,6 +1643,9 @@ They all return *NULL* or ``-1`` if an e
    Compare two strings and return ``-1``, ``0``, ``1`` for less than, equal, and greater than,
    respectively.
 
+   This function returns ``-1`` upon failure, so one should call
+   :c:func:`PyErr_Occurred` to check for errors.
+
 
 .. c:function:: int PyUnicode_CompareWithASCIIString(PyObject *uni, const char *string)
 
@@ -1651,6 +1654,9 @@ They all return *NULL* or ``-1`` if an e
    ASCII-encoded strings, but the function interprets the input string as
    ISO-8859-1 if it contains non-ASCII characters.
 
+   This function returns ``-1`` upon failure, so one should call
+   :c:func:`PyErr_Occurred` to check for errors.
+
 
 .. c:function:: PyObject* PyUnicode_RichCompare(PyObject *left,  PyObject *right,  int op)
 
diff -r ac93d188ebd6 Include/unicodeobject.h
--- a/Include/unicodeobject.h	Tue Nov 15 09:12:36 2016 +0100
+++ b/Include/unicodeobject.h	Tue Nov 15 21:20:16 2016 +0200
@@ -2048,6 +2048,17 @@ PyAPI_FUNC(int) PyUnicode_CompareWithASC
     const char *right           /* ASCII-encoded string */
     );
 
+#ifndef Py_LIMITED_API
+/* Test whether a unicode is equal to ASCII string.  Return 1 if true
+   otherwise 0.  Return 0 if any argument contains non-ASCII characters.
+   Any error occurs inside will be cleared before return. */
+
+PyAPI_FUNC(int) _PyUnicode_EqualToASCIIString(
+    PyObject *left,
+    const char *right           /* ASCII-encoded string */
+    );
+#endif
+
 /* Rich compare two strings and return one of the following:
 
    - NULL in case an exception was raised
diff -r ac93d188ebd6 Modules/_decimal/_decimal.c
--- a/Modules/_decimal/_decimal.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_decimal/_decimal.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1118,12 +1118,12 @@ context_getattr(PyObject *self, PyObject
     PyObject *retval;
 
     if (PyUnicode_Check(name)) {
-        if (PyUnicode_CompareWithASCIIString(name, "traps") == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, "traps")) {
             retval = ((PyDecContextObject *)self)->traps;
             Py_INCREF(retval);
             return retval;
         }
-        if (PyUnicode_CompareWithASCIIString(name, "flags") == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, "flags")) {
             retval = ((PyDecContextObject *)self)->flags;
             Py_INCREF(retval);
             return retval;
@@ -1143,10 +1143,10 @@ context_setattr(PyObject *self, PyObject
     }
 
     if (PyUnicode_Check(name)) {
-        if (PyUnicode_CompareWithASCIIString(name, "traps") == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, "traps")) {
             return context_settraps_dict(self, value);
         }
-        if (PyUnicode_CompareWithASCIIString(name, "flags") == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, "flags")) {
             return context_setstatus_dict(self, value);
         }
     }
@@ -2449,14 +2449,14 @@ dectuple_as_str(PyObject *dectuple)
     tmp = PyTuple_GET_ITEM(dectuple, 2);
     if (PyUnicode_Check(tmp)) {
         /* special */
-        if (PyUnicode_CompareWithASCIIString(tmp, "F") == 0) {
+        if (_PyUnicode_EqualToASCIIString(tmp, "F")) {
             strcat(sign_special, "Inf");
             is_infinite = 1;
         }
-        else if (PyUnicode_CompareWithASCIIString(tmp, "n") == 0) {
+        else if (_PyUnicode_EqualToASCIIString(tmp, "n")) {
             strcat(sign_special, "NaN");
         }
-        else if (PyUnicode_CompareWithASCIIString(tmp, "N") == 0) {
+        else if (_PyUnicode_EqualToASCIIString(tmp, "N")) {
             strcat(sign_special, "sNaN");
         }
         else {
diff -r ac93d188ebd6 Modules/_elementtree.c
--- a/Modules/_elementtree.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_elementtree.c	Tue Nov 15 21:20:16 2016 +0200
@@ -3661,11 +3661,11 @@ xmlparser_getattro(XMLParserObject* self
 {
     if (PyUnicode_Check(nameobj)) {
         PyObject* res;
-        if (PyUnicode_CompareWithASCIIString(nameobj, "entity") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "entity"))
             res = self->entity;
-        else if (PyUnicode_CompareWithASCIIString(nameobj, "target") == 0)
+        else if (_PyUnicode_EqualToASCIIString(nameobj, "target"))
             res = self->target;
-        else if (PyUnicode_CompareWithASCIIString(nameobj, "version") == 0) {
+        else if (_PyUnicode_EqualToASCIIString(nameobj, "version")) {
             return PyUnicode_FromFormat(
                 "Expat %d.%d.%d", XML_MAJOR_VERSION,
                 XML_MINOR_VERSION, XML_MICRO_VERSION);
diff -r ac93d188ebd6 Modules/_io/textio.c
--- a/Modules/_io/textio.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_io/textio.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1023,7 +1023,7 @@ static int
         else if (PyUnicode_Check(res)) {
             const encodefuncentry *e = encodefuncs;
             while (e->name != NULL) {
-                if (!PyUnicode_CompareWithASCIIString(res, e->name)) {
+                if (_PyUnicode_EqualToASCIIString(res, e->name)) {
                     self->encodefunc = e->encodefunc;
                     break;
                 }
diff -r ac93d188ebd6 Modules/_io/winconsoleio.c
--- a/Modules/_io/winconsoleio.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_io/winconsoleio.c	Tue Nov 15 21:20:16 2016 +0200
@@ -93,11 +93,11 @@ char _PyIO_get_console_type(PyObject *pa
     }
 
     char m = '\0';
-    if (PyUnicode_CompareWithASCIIString(decoded_upper, "CONIN$") == 0) {
+    if (_PyUnicode_EqualToASCIIString(decoded_upper, "CONIN$")) {
         m = 'r';
-    } else if (PyUnicode_CompareWithASCIIString(decoded_upper, "CONOUT$") == 0) {
+    } else if (_PyUnicode_EqualToASCIIString(decoded_upper, "CONOUT$")) {
         m = 'w';
-    } else if (PyUnicode_CompareWithASCIIString(decoded_upper, "CON") == 0) {
+    } else if (_PyUnicode_EqualToASCIIString(decoded_upper, "CON")) {
         m = 'x';
     }
 
diff -r ac93d188ebd6 Modules/_lsprof.c
--- a/Modules/_lsprof.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_lsprof.c	Tue Nov 15 21:20:16 2016 +0200
@@ -181,7 +181,7 @@ normalizeUserObj(PyObject *obj)
             }
         }
         if (modname != NULL) {
-            if (PyUnicode_CompareWithASCIIString(modname, "builtins") != 0) {
+            if (!_PyUnicode_EqualToASCIIString(modname, "builtins")) {
                 PyObject *result;
                 result = PyUnicode_FromFormat("<%U.%s>", modname,
                                               fn->m_ml->ml_name);
diff -r ac93d188ebd6 Modules/_pickle.c
--- a/Modules/_pickle.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_pickle.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1687,7 +1687,7 @@ whichmodule(PyObject *global, PyObject *
     while (PyDict_Next(modules_dict, &i, &module_name, &module)) {
         PyObject *candidate;
         if (PyUnicode_Check(module_name) &&
-            !PyUnicode_CompareWithASCIIString(module_name, "__main__"))
+            _PyUnicode_EqualToASCIIString(module_name, "__main__"))
             continue;
         if (module == Py_None)
             continue;
diff -r ac93d188ebd6 Modules/_sqlite/connection.c
--- a/Modules/_sqlite/connection.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_sqlite/connection.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1191,7 +1191,7 @@ static int pysqlite_connection_set_isola
             return -1;
         }
         for (candidate = begin_statements; *candidate; candidate++) {
-            if (!PyUnicode_CompareWithASCIIString(uppercase_level, *candidate + 6))
+            if (_PyUnicode_EqualToASCIIString(uppercase_level, *candidate + 6))
                 break;
         }
         Py_DECREF(uppercase_level);
diff -r ac93d188ebd6 Modules/_testcapimodule.c
--- a/Modules/_testcapimodule.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/_testcapimodule.c	Tue Nov 15 21:20:16 2016 +0200
@@ -2325,7 +2325,7 @@ test_string_from_format(PyObject *self, 
     result = PyUnicode_FromFormat(FORMAT, (TYPE)1);                 \
     if (result == NULL)                                             \
         return NULL;                                                \
-    if (PyUnicode_CompareWithASCIIString(result, "1")) {     \
+    if (!_PyUnicode_EqualToASCIIString(result, "1")) {              \
         msg = FORMAT " failed at 1";                                \
         goto Fail;                                                  \
     }                                                               \
diff -r ac93d188ebd6 Modules/pyexpat.c
--- a/Modules/pyexpat.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Modules/pyexpat.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1244,8 +1244,7 @@ handlername2int(PyObject *name)
 {
     int i;
     for (i = 0; handler_info[i].name != NULL; i++) {
-        if (PyUnicode_CompareWithASCIIString(
-                name, handler_info[i].name) == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, handler_info[i].name)) {
             return i;
         }
     }
@@ -1283,45 +1282,45 @@ xmlparse_getattro(xmlparseobject *self, 
 
     first_char = PyUnicode_READ_CHAR(nameobj, 0);
     if (first_char == 'E') {
-        if (PyUnicode_CompareWithASCIIString(nameobj, "ErrorCode") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "ErrorCode"))
             return PyLong_FromLong((long)
                                   XML_GetErrorCode(self->itself));
-        if (PyUnicode_CompareWithASCIIString(nameobj, "ErrorLineNumber") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "ErrorLineNumber"))
             return PyLong_FromLong((long)
                                   XML_GetErrorLineNumber(self->itself));
-        if (PyUnicode_CompareWithASCIIString(nameobj, "ErrorColumnNumber") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "ErrorColumnNumber"))
             return PyLong_FromLong((long)
                                   XML_GetErrorColumnNumber(self->itself));
-        if (PyUnicode_CompareWithASCIIString(nameobj, "ErrorByteIndex") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "ErrorByteIndex"))
             return PyLong_FromLong((long)
                                   XML_GetErrorByteIndex(self->itself));
     }
     if (first_char == 'C') {
-        if (PyUnicode_CompareWithASCIIString(nameobj, "CurrentLineNumber") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "CurrentLineNumber"))
             return PyLong_FromLong((long)
                                   XML_GetCurrentLineNumber(self->itself));
-        if (PyUnicode_CompareWithASCIIString(nameobj, "CurrentColumnNumber") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "CurrentColumnNumber"))
             return PyLong_FromLong((long)
                                   XML_GetCurrentColumnNumber(self->itself));
-        if (PyUnicode_CompareWithASCIIString(nameobj, "CurrentByteIndex") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "CurrentByteIndex"))
             return PyLong_FromLong((long)
                                   XML_GetCurrentByteIndex(self->itself));
     }
     if (first_char == 'b') {
-        if (PyUnicode_CompareWithASCIIString(nameobj, "buffer_size") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "buffer_size"))
             return PyLong_FromLong((long) self->buffer_size);
-        if (PyUnicode_CompareWithASCIIString(nameobj, "buffer_text") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "buffer_text"))
             return get_pybool(self->buffer != NULL);
-        if (PyUnicode_CompareWithASCIIString(nameobj, "buffer_used") == 0)
+        if (_PyUnicode_EqualToASCIIString(nameobj, "buffer_used"))
             return PyLong_FromLong((long) self->buffer_used);
     }
-    if (PyUnicode_CompareWithASCIIString(nameobj, "namespace_prefixes") == 0)
+    if (_PyUnicode_EqualToASCIIString(nameobj, "namespace_prefixes"))
         return get_pybool(self->ns_prefixes);
-    if (PyUnicode_CompareWithASCIIString(nameobj, "ordered_attributes") == 0)
+    if (_PyUnicode_EqualToASCIIString(nameobj, "ordered_attributes"))
         return get_pybool(self->ordered_attributes);
-    if (PyUnicode_CompareWithASCIIString(nameobj, "specified_attributes") == 0)
+    if (_PyUnicode_EqualToASCIIString(nameobj, "specified_attributes"))
         return get_pybool((long) self->specified_attributes);
-    if (PyUnicode_CompareWithASCIIString(nameobj, "intern") == 0) {
+    if (_PyUnicode_EqualToASCIIString(nameobj, "intern")) {
         if (self->intern == NULL) {
             Py_INCREF(Py_None);
             return Py_None;
@@ -1383,7 +1382,7 @@ xmlparse_setattro(xmlparseobject *self, 
         PyErr_SetString(PyExc_RuntimeError, "Cannot delete attribute");
         return -1;
     }
-    if (PyUnicode_CompareWithASCIIString(name, "buffer_text") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "buffer_text")) {
         int b = PyObject_IsTrue(v);
         if (b < 0)
             return -1;
@@ -1405,7 +1404,7 @@ xmlparse_setattro(xmlparseobject *self, 
         }
         return 0;
     }
-    if (PyUnicode_CompareWithASCIIString(name, "namespace_prefixes") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "namespace_prefixes")) {
         int b = PyObject_IsTrue(v);
         if (b < 0)
             return -1;
@@ -1413,14 +1412,14 @@ xmlparse_setattro(xmlparseobject *self, 
         XML_SetReturnNSTriplet(self->itself, self->ns_prefixes);
         return 0;
     }
-    if (PyUnicode_CompareWithASCIIString(name, "ordered_attributes") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "ordered_attributes")) {
         int b = PyObject_IsTrue(v);
         if (b < 0)
             return -1;
         self->ordered_attributes = b;
         return 0;
     }
-    if (PyUnicode_CompareWithASCIIString(name, "specified_attributes") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "specified_attributes")) {
         int b = PyObject_IsTrue(v);
         if (b < 0)
             return -1;
@@ -1428,7 +1427,7 @@ xmlparse_setattro(xmlparseobject *self, 
         return 0;
     }
 
-    if (PyUnicode_CompareWithASCIIString(name, "buffer_size") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "buffer_size")) {
       long new_buffer_size;
       if (!PyLong_Check(v)) {
         PyErr_SetString(PyExc_TypeError, "buffer_size must be an integer");
@@ -1474,7 +1473,7 @@ xmlparse_setattro(xmlparseobject *self, 
       return 0;
     }
 
-    if (PyUnicode_CompareWithASCIIString(name, "CharacterDataHandler") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "CharacterDataHandler")) {
         /* If we're changing the character data handler, flush all
          * cached data with the old handler.  Not sure there's a
          * "right" thing to do, though, but this probably won't
diff -r ac93d188ebd6 Objects/longobject.c
--- a/Objects/longobject.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Objects/longobject.c	Tue Nov 15 21:20:16 2016 +0200
@@ -5166,9 +5166,9 @@ long_to_bytes(PyLongObject *v, PyObject 
         return NULL;
     }
 
-    if (!PyUnicode_CompareWithASCIIString(byteorder_str, "little"))
+    if (_PyUnicode_EqualToASCIIString(byteorder_str, "little"))
         little_endian = 1;
-    else if (!PyUnicode_CompareWithASCIIString(byteorder_str, "big"))
+    else if (_PyUnicode_EqualToASCIIString(byteorder_str, "big"))
         little_endian = 0;
     else {
         PyErr_SetString(PyExc_ValueError,
@@ -5249,9 +5249,9 @@ long_from_bytes(PyTypeObject *type, PyOb
         return NULL;
     }
 
-    if (!PyUnicode_CompareWithASCIIString(byteorder_str, "little"))
+    if (_PyUnicode_EqualToASCIIString(byteorder_str, "little"))
         little_endian = 1;
-    else if (!PyUnicode_CompareWithASCIIString(byteorder_str, "big"))
+    else if (_PyUnicode_EqualToASCIIString(byteorder_str, "big"))
         little_endian = 0;
     else {
         PyErr_SetString(PyExc_ValueError,
diff -r ac93d188ebd6 Objects/moduleobject.c
--- a/Objects/moduleobject.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Objects/moduleobject.c	Tue Nov 15 21:20:16 2016 +0200
@@ -586,7 +586,7 @@ void
     while (PyDict_Next(d, &pos, &key, &value)) {
         if (value != Py_None && PyUnicode_Check(key)) {
             if (PyUnicode_READ_CHAR(key, 0) != '_' ||
-                PyUnicode_CompareWithASCIIString(key, "__builtins__") != 0)
+                !_PyUnicode_EqualToASCIIString(key, "__builtins__"))
             {
                 if (Py_VerboseFlag > 1) {
                     const char *s = _PyUnicode_AsString(key);
diff -r ac93d188ebd6 Objects/typeobject.c
--- a/Objects/typeobject.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Objects/typeobject.c	Tue Nov 15 21:20:16 2016 +0200
@@ -2412,7 +2412,7 @@ type_new(PyTypeObject *metatype, PyObjec
                 }
                 add_dict++;
             }
-            if (PyUnicode_CompareWithASCIIString(tmp, "__weakref__") == 0) {
+            if (_PyUnicode_EqualToASCIIString(tmp, "__weakref__")) {
                 if (!may_add_weak || add_weak) {
                     PyErr_SetString(PyExc_TypeError,
                         "__weakref__ slot disallowed: "
@@ -2436,7 +2436,7 @@ type_new(PyTypeObject *metatype, PyObjec
             if ((add_dict &&
                  _PyUnicode_CompareWithId(tmp, &PyId___dict__) == 0) ||
                 (add_weak &&
-                 PyUnicode_CompareWithASCIIString(tmp, "__weakref__") == 0))
+                 _PyUnicode_EqualToASCIIString(tmp, "__weakref__")))
                 continue;
             tmp =_Py_Mangle(name, tmp);
             if (!tmp) {
diff -r ac93d188ebd6 Objects/unicodeobject.c
--- a/Objects/unicodeobject.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Objects/unicodeobject.c	Tue Nov 15 21:20:16 2016 +0200
@@ -11048,6 +11048,41 @@ PyUnicode_CompareWithASCIIString(PyObjec
     }
 }
 
+static int
+non_ready_unicode_equal_to_ascii_string(PyObject *unicode, const char *str)
+{
+    size_t i, len;
+    const wchar_t *p;
+    len = (size_t)_PyUnicode_WSTR_LENGTH(unicode);
+    if (strlen(str) != len)
+        return 0;
+    p = _PyUnicode_WSTR(unicode);
+    assert(p);
+    for (i = 0; i < len; i++) {
+        unsigned char c = (unsigned char)str[i];
+        if (c > 128 || p[i] != (wchar_t)c)
+            return 0;
+    }
+    return 1;
+}
+
+int
+_PyUnicode_EqualToASCIIString(PyObject *unicode, const char *str)
+{
+    size_t len;
+    assert(_PyUnicode_CHECK(unicode));
+    if (PyUnicode_READY(unicode) == -1) {
+        /* Memory error or bad data */
+        PyErr_Clear();
+        return non_ready_unicode_equal_to_ascii_string(unicode, str);
+    }
+    if (!PyUnicode_IS_ASCII(unicode))
+        return 0;
+    len = (size_t)PyUnicode_GET_LENGTH(unicode);
+    return strlen(str) == len &&
+           memcmp(PyUnicode_1BYTE_DATA(unicode), str, len) == 0;
+}
+
 
 #define TEST_COND(cond)                         \
     ((cond) ? Py_True : Py_False)
diff -r ac93d188ebd6 Python/_warnings.c
--- a/Python/_warnings.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/_warnings.c	Tue Nov 15 21:20:16 2016 +0200
@@ -503,7 +503,7 @@ warn_explicit(PyObject *category, PyObje
     if (action == NULL)
         goto cleanup;
 
-    if (PyUnicode_CompareWithASCIIString(action, "error") == 0) {
+    if (_PyUnicode_EqualToASCIIString(action, "error")) {
         PyErr_SetObject(category, message);
         goto cleanup;
     }
@@ -511,13 +511,13 @@ warn_explicit(PyObject *category, PyObje
     /* Store in the registry that we've been here, *except* when the action
        is "always". */
     rc = 0;
-    if (PyUnicode_CompareWithASCIIString(action, "always") != 0) {
+    if (!_PyUnicode_EqualToASCIIString(action, "always")) {
         if (registry != NULL && registry != Py_None &&
                 PyDict_SetItem(registry, key, Py_True) < 0)
             goto cleanup;
-        else if (PyUnicode_CompareWithASCIIString(action, "ignore") == 0)
+        else if (_PyUnicode_EqualToASCIIString(action, "ignore"))
             goto return_none;
-        else if (PyUnicode_CompareWithASCIIString(action, "once") == 0) {
+        else if (_PyUnicode_EqualToASCIIString(action, "once")) {
             if (registry == NULL || registry == Py_None) {
                 registry = get_once_registry();
                 if (registry == NULL)
@@ -526,12 +526,12 @@ warn_explicit(PyObject *category, PyObje
             /* _once_registry[(text, category)] = 1 */
             rc = update_registry(registry, text, category, 0);
         }
-        else if (PyUnicode_CompareWithASCIIString(action, "module") == 0) {
+        else if (_PyUnicode_EqualToASCIIString(action, "module")) {
             /* registry[(text, category, 0)] = 1 */
             if (registry != NULL && registry != Py_None)
                 rc = update_registry(registry, text, category, 0);
         }
-        else if (PyUnicode_CompareWithASCIIString(action, "default") != 0) {
+        else if (!_PyUnicode_EqualToASCIIString(action, "default")) {
             PyErr_Format(PyExc_RuntimeError,
                         "Unrecognized action (%R) in warnings.filters:\n %R",
                         action, item);
@@ -715,7 +715,7 @@ setup_context(Py_ssize_t stack_level, Py
     }
     else {
         *filename = NULL;
-        if (*module != Py_None && PyUnicode_CompareWithASCIIString(*module, "__main__") == 0) {
+        if (*module != Py_None && _PyUnicode_EqualToASCIIString(*module, "__main__")) {
             PyObject *argv = _PySys_GetObjectId(&PyId_argv);
             /* PyList_Check() is needed because sys.argv is set to None during
                Python finalization */
diff -r ac93d188ebd6 Python/ast.c
--- a/Python/ast.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/ast.c	Tue Nov 15 21:20:16 2016 +0200
@@ -934,12 +934,12 @@ forbidden_name(struct compiling *c, iden
                int full_checks)
 {
     assert(PyUnicode_Check(name));
-    if (PyUnicode_CompareWithASCIIString(name, "__debug__") == 0) {
+    if (_PyUnicode_EqualToASCIIString(name, "__debug__")) {
         ast_error(c, n, "assignment to keyword");
         return 1;
     }
-    if (PyUnicode_CompareWithASCIIString(name, "async") == 0 ||
-        PyUnicode_CompareWithASCIIString(name, "await") == 0)
+    if (_PyUnicode_EqualToASCIIString(name, "async") ||
+        _PyUnicode_EqualToASCIIString(name, "await"))
     {
         PyObject *message = PyUnicode_FromString(
             "'async' and 'await' will become reserved keywords"
@@ -963,7 +963,7 @@ forbidden_name(struct compiling *c, iden
     if (full_checks) {
         const char * const *p;
         for (p = FORBIDDEN; *p; p++) {
-            if (PyUnicode_CompareWithASCIIString(name, *p) == 0) {
+            if (_PyUnicode_EqualToASCIIString(name, *p)) {
                 ast_error(c, n, "assignment to keyword");
                 return 1;
             }
diff -r ac93d188ebd6 Python/compile.c
--- a/Python/compile.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/compile.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1522,7 +1522,7 @@ get_ref_type(struct compiler *c, PyObjec
 {
     int scope;
     if (c->u->u_scope_type == COMPILER_SCOPE_CLASS &&
-        !PyUnicode_CompareWithASCIIString(name, "__class__"))
+        _PyUnicode_EqualToASCIIString(name, "__class__"))
         return CELL;
     scope = PyST_GetScope(c->u->u_ste, name);
     if (scope == 0) {
@@ -2688,7 +2688,7 @@ compiler_from_import(struct compiler *c,
     }
 
     if (s->lineno > c->c_future->ff_lineno && s->v.ImportFrom.module &&
-        !PyUnicode_CompareWithASCIIString(s->v.ImportFrom.module, "__future__")) {
+        _PyUnicode_EqualToASCIIString(s->v.ImportFrom.module, "__future__")) {
         Py_DECREF(level);
         Py_DECREF(names);
         return compiler_error(c, "from __future__ imports must occur "
@@ -3027,9 +3027,9 @@ compiler_nameop(struct compiler *c, iden
     if (!mangled)
         return 0;
 
-    assert(PyUnicode_CompareWithASCIIString(name, "None") &&
-           PyUnicode_CompareWithASCIIString(name, "True") &&
-           PyUnicode_CompareWithASCIIString(name, "False"));
+    assert(!_PyUnicode_EqualToASCIIString(name, "None") &&
+           !_PyUnicode_EqualToASCIIString(name, "True") &&
+           !_PyUnicode_EqualToASCIIString(name, "False"));
 
     op = 0;
     optype = OP_NAME;
diff -r ac93d188ebd6 Python/future.c
--- a/Python/future.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/future.c	Tue Nov 15 21:20:16 2016 +0200
@@ -102,7 +102,7 @@ future_parse(PyFutureFeatures *ff, mod_t
         if (s->kind == ImportFrom_kind) {
             identifier modname = s->v.ImportFrom.module;
             if (modname &&
-                !PyUnicode_CompareWithASCIIString(modname, "__future__")) {
+                _PyUnicode_EqualToASCIIString(modname, "__future__")) {
                 if (done) {
                     PyErr_SetString(PyExc_SyntaxError,
                                     ERR_LATE_FUTURE);
diff -r ac93d188ebd6 Python/getargs.c
--- a/Python/getargs.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/getargs.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1808,7 +1808,7 @@ vgetargskeywords(PyObject *args, PyObjec
                 return cleanreturn(0, &freelist);
             }
             for (i = 0; i < len; i++) {
-                if (*kwlist[i] && !PyUnicode_CompareWithASCIIString(key, kwlist[i])) {
+                if (*kwlist[i] && _PyUnicode_EqualToASCIIString(key, kwlist[i])) {
                     match = 1;
                     break;
                 }
diff -r ac93d188ebd6 Python/import.c
--- a/Python/import.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/import.c	Tue Nov 15 21:20:16 2016 +0200
@@ -936,10 +936,9 @@ static const struct _frozen * find_froze
 static int
 is_builtin(PyObject *name)
 {
-    int i, cmp;
+    int i;
     for (i = 0; PyImport_Inittab[i].name != NULL; i++) {
-        cmp = PyUnicode_CompareWithASCIIString(name, PyImport_Inittab[i].name);
-        if (cmp == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, PyImport_Inittab[i].name)) {
             if (PyImport_Inittab[i].initfunc == NULL)
                 return -1;
             else
@@ -1059,7 +1058,7 @@ static PyObject *
 
     for (p = PyImport_Inittab; p->name != NULL; p++) {
         PyModuleDef *def;
-        if (PyUnicode_CompareWithASCIIString(name, p->name) == 0) {
+        if (_PyUnicode_EqualToASCIIString(name, p->name)) {
             if (p->initfunc == NULL) {
                 /* Cannot re-init internal module ("sys" or "builtins") */
                 mod = PyImport_AddModule(namestr);
@@ -1109,7 +1108,7 @@ find_frozen(PyObject *name)
     for (p = PyImport_FrozenModules; ; p++) {
         if (p->name == NULL)
             return NULL;
-        if (PyUnicode_CompareWithASCIIString(name, p->name) == 0)
+        if (_PyUnicode_EqualToASCIIString(name, p->name))
             break;
     }
     return p;
@@ -1310,12 +1309,8 @@ remove_importlib_frames(void)
         int now_in_importlib;
 
         assert(PyTraceBack_Check(tb));
-        now_in_importlib = (PyUnicode_CompareWithASCIIString(
-                                code->co_filename,
-                                importlib_filename) == 0) ||
-                           (PyUnicode_CompareWithASCIIString(
-                                code->co_filename,
-                                external_filename) == 0);
+        now_in_importlib = _PyUnicode_EqualToASCIIString(code->co_filename, importlib_filename) ||
+                           _PyUnicode_EqualToASCIIString(code->co_filename, external_filename);
         if (now_in_importlib && !in_importlib) {
             /* This is the link to this chunk of importlib tracebacks */
             outer_link = prev_link;
@@ -1324,8 +1319,7 @@ remove_importlib_frames(void)
 
         if (in_importlib &&
             (always_trim ||
-             PyUnicode_CompareWithASCIIString(code->co_name,
-                                              remove_frames) == 0)) {
+             _PyUnicode_EqualToASCIIString(code->co_name, remove_frames))) {
             Py_XINCREF(next);
             Py_XSETREF(*outer_link, next);
             prev_link = outer_link;
diff -r ac93d188ebd6 Python/symtable.c
--- a/Python/symtable.c	Tue Nov 15 09:12:36 2016 +0100
+++ b/Python/symtable.c	Tue Nov 15 21:20:16 2016 +0200
@@ -1503,7 +1503,7 @@ symtable_visit_expr(struct symtable *st,
         /* Special-case super: it counts as a use of __class__ */
         if (e->v.Name.ctx == Load &&
             st->st_cur->ste_type == FunctionBlock &&
-            !PyUnicode_CompareWithASCIIString(e->v.Name.id, "super")) {
+            _PyUnicode_EqualToASCIIString(e->v.Name.id, "super")) {
             if (!GET_IDENTIFIER(__class__) ||
                 !symtable_add_def(st, __class__, USE))
                 VISIT_QUIT(st, 0);
@@ -1652,7 +1652,7 @@ symtable_visit_alias(struct symtable *st
         store_name = name;
         Py_INCREF(store_name);
     }
-    if (PyUnicode_CompareWithASCIIString(name, "*")) {
+    if (!_PyUnicode_EqualToASCIIString(name, "*")) {
         int r = symtable_add_def(st, store_name, DEF_IMPORT);
         Py_DECREF(store_name);
         return r;