Only define _Py_ABI_SLOT as a part of the internal C API

Author: befeleme

Include/cpython/modsupport.h

@@ -38,6 +38,8 @@ typedef struct _PyArg_Parser {
 PyAPI_FUNC(int) _PyArg_ParseTupleAndKeywordsFast(PyObject *, PyObject *,
                                                  struct _PyArg_Parser *, ...);
 
+#ifdef Py_BUILD_CORE
 // For internal use in stdlib. Needs C99 compound literals.
 // Defined here to avoid every stdlib module including pycore_modsupport.h
 #define _Py_ABI_SLOT {Py_mod_abi, (void*) &(PyABIInfo) _PyABIInfo_DEFAULT}
+#endif

Modules/_xxtestfuzz/_xxtestfuzz.c

@@ -28,8 +28,10 @@ static PyMethodDef module_methods[] = {
     {NULL},
 };
 
+PyABIInfo_VAR(abi_info);
+
 static PyModuleDef_Slot module_slots[] = {
-    _Py_ABI_SLOT,
+    {Py_mod_abi, &abi_info},
     {Py_mod_gil, Py_MOD_GIL_NOT_USED},
     {0, NULL},
 };

Modules/xxsubtype.c

@@ -301,8 +301,10 @@ xxsubtype_exec(PyObject* m)
     return 0;
 }
 
+PyABIInfo_VAR(abi_info);
+
 static struct PyModuleDef_Slot xxsubtype_slots[] = {
-    _Py_ABI_SLOT,
+    {Py_mod_abi, &abi_info},
     {Py_mod_exec, xxsubtype_exec},
     {Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
     {Py_mod_gil, Py_MOD_GIL_NOT_USED},