@@ -776,7 +776,6 @@ Py_SetPath
 Py_SetProgramName
 Py_SetPythonHome
 Py_SetRecursionLimit
-Py_SymtableString
 Py_UTF8Mode
 Py_VaBuildValue
 Py_XNewRef
@@ -1364,3 +1364,19 @@ Removed
   AST object (``mod_ty`` type) with the public C API. The function was already
   excluded from the limited C API (:pep:`384`).
   (Contributed by Victor Stinner in :issue:`43244`.)
+
+* Remove the ``symtable.h`` header file and the undocumented functions:
+
+  * ``PyST_GetScope()``
+  * ``PySymtable_Build()``
+  * ``PySymtable_BuildObject()``
+  * ``PySymtable_Free()``
+  * ``Py_SymtableString()``
+  * ``Py_SymtableStringObject()``
+
+  The ``Py_SymtableString()`` function was part the stable ABI by mistake but
+  it could not be used, because the ``symtable.h`` header file was excluded
+  from the limited C API.
+
+  The Python :mod:`symtable` module remains available and is unchanged.
+  (Contributed by Victor Stinner in :issue:`43244`.)
@@ -77,17 +77,6 @@ PyAPI_FUNC(const char *) _Py_SourceAsString(
     PyCompilerFlags *cf,
     PyObject **cmd_copy);
 
-PyAPI_FUNC(struct symtable *) Py_SymtableStringObject(
-    const char *str,
-    PyObject *filename,
-    int start);
-
-PyAPI_FUNC(struct symtable *) _Py_SymtableStringObjectFlags(
-    const char *str,
-    PyObject *filename,
-    int start,
-    PyCompilerFlags *flags);
-
 
 /* A function flavor is also exported by libpython. It is required when
     libpython is accessed directly rather than using header files which defines
 
@@ -1,15 +1,14 @@
-#ifndef Py_LIMITED_API
-#ifndef Py_SYMTABLE_H
-#define Py_SYMTABLE_H
+#ifndef Py_INTERNAL_SYMTABLE_H
+#define Py_INTERNAL_SYMTABLE_H
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#include "Python-ast.h"   /* mod_ty */
+#ifndef Py_BUILD_CORE
+#  error "this header requires Py_BUILD_CORE define"
+#endif
 
-/* XXX(ncoghlan): This is a weird mix of public names and interpreter internal
- *                names.
- */
+#include "Python-ast.h"   /* mod_ty */
 
 typedef enum _block_type { FunctionBlock, ClassBlock, ModuleBlock }
     _Py_block_ty;
@@ -68,23 +67,19 @@ typedef struct _symtable_entry {
     struct symtable *ste_table;
 } PySTEntryObject;
 
-PyAPI_DATA(PyTypeObject) PySTEntry_Type;
+extern PyTypeObject PySTEntry_Type;
 
 #define PySTEntry_Check(op) Py_IS_TYPE(op, &PySTEntry_Type)
 
-PyAPI_FUNC(int) PyST_GetScope(PySTEntryObject *, PyObject *);
+extern int _PyST_GetScope(PySTEntryObject *, PyObject *);
 
-PyAPI_FUNC(struct symtable *) PySymtable_Build(
-    mod_ty mod,
-    const char *filename,       /* decoded from the filesystem encoding */
-    PyFutureFeatures *future);
-PyAPI_FUNC(struct symtable *) PySymtable_BuildObject(
+extern struct symtable* _PySymtable_Build(
     mod_ty mod,
     PyObject *filename,
     PyFutureFeatures *future);
 PyAPI_FUNC(PySTEntryObject *) PySymtable_Lookup(struct symtable *, void *);
 
-PyAPI_FUNC(void) PySymtable_Free(struct symtable *);
+extern void _PySymtable_Free(struct symtable *);
 
 /* Flags for def-use information */
 
@@ -117,8 +112,14 @@ PyAPI_FUNC(void) PySymtable_Free(struct symtable *);
 #define GENERATOR 1
 #define GENERATOR_EXPRESSION 2
 
+// Used by symtablemodule.c
+extern struct symtable* _Py_SymtableStringObjectFlags(
+    const char *str,
+    PyObject *filename,
+    int start,
+    PyCompilerFlags *flags);
+
 #ifdef __cplusplus
 }
 #endif
-#endif /* !Py_SYMTABLE_H */
-#endif /* !Py_LIMITED_API */
+#endif /* !Py_INTERNAL_SYMTABLE_H */
@@ -9,11 +9,6 @@ extern "C" {
 
 PyAPI_FUNC(PyObject *) Py_CompileString(const char *, const char *, int);
 
-PyAPI_FUNC(struct symtable *) Py_SymtableString(
-    const char *str,
-    const char *filename,       /* decoded from the filesystem encoding */
-    int start);
-
 PyAPI_FUNC(void) PyErr_Print(void);
 PyAPI_FUNC(void) PyErr_PrintEx(int);
 PyAPI_FUNC(void) PyErr_Display(PyObject *, PyObject *, PyObject *);
 
@@ -1087,7 +1087,6 @@ PYTHON_HEADERS= \
 		$(srcdir)/Include/sliceobject.h \
 		$(srcdir)/Include/structmember.h \
 		$(srcdir)/Include/structseq.h \
-		$(srcdir)/Include/symtable.h \
 		$(srcdir)/Include/sysmodule.h \
 		$(srcdir)/Include/token.h \
 		$(srcdir)/Include/traceback.h \
@@ -1167,6 +1166,7 @@ PYTHON_HEADERS= \
 		$(srcdir)/Include/internal/pycore_pymem.h \
 		$(srcdir)/Include/internal/pycore_pystate.h \
 		$(srcdir)/Include/internal/pycore_runtime.h \
+		$(srcdir)/Include/internal/pycore_symtable.h \
 		$(srcdir)/Include/internal/pycore_sysmodule.h \
 		$(srcdir)/Include/internal/pycore_traceback.h \
 		$(srcdir)/Include/internal/pycore_tuple.h \
 
@@ -0,0 +1,16 @@
+Remove the ``symtable.h`` header file and the undocumented functions:
+
+* ``PyST_GetScope()``
+* ``PySymtable_Build()``
+* ``PySymtable_BuildObject()``
+* ``PySymtable_Free()``
+* ``Py_SymtableString()``
+* ``Py_SymtableStringObject()``
+
+The ``Py_SymtableString()`` function was part the stable ABI by mistake but it
+could not be used, because the ``symtable.h`` header file was excluded from the
+limited C API.
+
+The Python :mod:`symtable` module remains available and is unchanged.
+
+Patch by Victor Stinner.
@@ -1,8 +1,7 @@
 #include "Python.h"
 
-#include "code.h"
 #include "Python-ast.h"
-#include "symtable.h"
+#include "pycore_symtable.h"      // struct symtable
 
 #include "clinic/symtablemodule.c.h"
 /*[clinic input]
@@ -62,7 +61,7 @@ _symtable_symtable_impl(PyObject *module, PyObject *source,
     t = (PyObject *)st->st_top;
     Py_INCREF(t);
     PyMem_Free((void *)st->st_future);
-    PySymtable_Free(st);
+    _PySymtable_Free(st);
     return t;
 }
 
 
@@ -80,7 +80,6 @@ EXPORT_FUNC(Py_SetPath)
 EXPORT_FUNC(Py_SetProgramName)
 EXPORT_FUNC(Py_SetPythonHome)
 EXPORT_FUNC(Py_SetRecursionLimit)
-EXPORT_FUNC(Py_SymtableString)
 EXPORT_FUNC(Py_VaBuildValue)
 EXPORT_FUNC(Py_XNewRef)
 EXPORT_FUNC(PyArg_Parse)
 
@@ -208,6 +208,7 @@
     <ClInclude Include="..\Include\internal\pycore_pystate.h" />
     <ClInclude Include="..\Include\internal\pycore_runtime.h" />
     <ClInclude Include="..\Include\internal\pycore_sysmodule.h" />
+    <ClInclude Include="..\Include\internal\pycore_symtable.h" />
     <ClInclude Include="..\Include\internal\pycore_traceback.h" />
     <ClInclude Include="..\Include\internal\pycore_tuple.h" />
     <ClInclude Include="..\Include\internal\pycore_ucnhash.h" />