diff --git a/Objects/stringlib/asciilib.h b/Objects/stringlib/asciilib.h
index f62813d2fd1..d0fc18d22fa 100644
--- a/Objects/stringlib/asciilib.h
+++ b/Objects/stringlib/asciilib.h
@@ -19,7 +19,6 @@
 #define STRINGLIB_STR            PyUnicode_1BYTE_DATA
 #define STRINGLIB_LEN            PyUnicode_GET_LENGTH
 #define STRINGLIB_NEW(STR,LEN)   _PyUnicode_FromASCII((char*)(STR),(LEN))
-#define STRINGLIB_RESIZE         not_supported
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact
 
diff --git a/Objects/stringlib/stringdefs.h b/Objects/stringlib/stringdefs.h
index 7bb91a7a5b7..ce27f3e4081 100644
--- a/Objects/stringlib/stringdefs.h
+++ b/Objects/stringlib/stringdefs.h
@@ -21,7 +21,6 @@
 #define STRINGLIB_STR            PyBytes_AS_STRING
 #define STRINGLIB_LEN            PyBytes_GET_SIZE
 #define STRINGLIB_NEW            PyBytes_FromStringAndSize
-#define STRINGLIB_RESIZE         _PyBytes_Resize
 #define STRINGLIB_CHECK          PyBytes_Check
 #define STRINGLIB_CHECK_EXACT    PyBytes_CheckExact
 #define STRINGLIB_TOSTR          PyObject_Str
diff --git a/Objects/stringlib/ucs1lib.h b/Objects/stringlib/ucs1lib.h
index e8c6fcb85f0..ce1eb57f0d7 100644
--- a/Objects/stringlib/ucs1lib.h
+++ b/Objects/stringlib/ucs1lib.h
@@ -19,7 +19,6 @@
 #define STRINGLIB_STR            PyUnicode_1BYTE_DATA
 #define STRINGLIB_LEN            PyUnicode_GET_LENGTH
 #define STRINGLIB_NEW            _PyUnicode_FromUCS1
-#define STRINGLIB_RESIZE         not_supported
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact
 
diff --git a/Objects/stringlib/ucs2lib.h b/Objects/stringlib/ucs2lib.h
index 45e572963d2..f900cb65f8c 100644
--- a/Objects/stringlib/ucs2lib.h
+++ b/Objects/stringlib/ucs2lib.h
@@ -19,7 +19,6 @@
 #define STRINGLIB_STR            PyUnicode_2BYTE_DATA
 #define STRINGLIB_LEN            PyUnicode_GET_LENGTH
 #define STRINGLIB_NEW            _PyUnicode_FromUCS2
-#define STRINGLIB_RESIZE         not_supported
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact
 
diff --git a/Objects/stringlib/ucs4lib.h b/Objects/stringlib/ucs4lib.h
index 647a27e233d..86a480f1e3a 100644
--- a/Objects/stringlib/ucs4lib.h
+++ b/Objects/stringlib/ucs4lib.h
@@ -19,7 +19,6 @@
 #define STRINGLIB_STR            PyUnicode_4BYTE_DATA
 #define STRINGLIB_LEN            PyUnicode_GET_LENGTH
 #define STRINGLIB_NEW            _PyUnicode_FromUCS4
-#define STRINGLIB_RESIZE         not_supported
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact
 
diff --git a/Objects/stringlib/undef.h b/Objects/stringlib/undef.h
index 03117ec4434..f9d3f1d3328 100644
--- a/Objects/stringlib/undef.h
+++ b/Objects/stringlib/undef.h
@@ -6,7 +6,6 @@
 #undef  STRINGLIB_STR
 #undef  STRINGLIB_LEN
 #undef  STRINGLIB_NEW
-#undef  STRINGLIB_RESIZE
 #undef  _Py_InsertThousandsGrouping
 #undef STRINGLIB_IS_UNICODE
 
diff --git a/Objects/stringlib/unicodedefs.h b/Objects/stringlib/unicodedefs.h
index f16f21e60c3..48d00eccd04 100644
--- a/Objects/stringlib/unicodedefs.h
+++ b/Objects/stringlib/unicodedefs.h
@@ -21,7 +21,6 @@
 #define STRINGLIB_STR            PyUnicode_AS_UNICODE
 #define STRINGLIB_LEN            PyUnicode_GET_SIZE
 #define STRINGLIB_NEW            PyUnicode_FromUnicode
-#define STRINGLIB_RESIZE         PyUnicode_Resize
 #define STRINGLIB_CHECK          PyUnicode_Check
 #define STRINGLIB_CHECK_EXACT    PyUnicode_CheckExact