bpo-43244: Remove the pyarena.h header (GH-25007)

Remove the pyarena.h header file with functions:

* PyArena_New()
* PyArena_Free()
* PyArena_Malloc()
* PyArena_AddPyObject()

These functions were undocumented, excluded from the limited C API,
and were only used internally by the compiler.

Add pycore_pyarena.h header. Rename functions:

* PyArena_New() => _PyArena_New()
* PyArena_Free() => _PyArena_Free()
* PyArena_Malloc() => _PyArena_Malloc()
* PyArena_AddPyObject() => _PyArena_AddPyObject()

Doc/whatsnew/3.10.rst

@@ -1419,3 +1419,14 @@ Removed
 
   These functions were undocumented and excluded from the limited C API.
   (Contributed by Victor Stinner in :issue:`43244`.)
+
+* Remove the ``pyarena.h`` header file with functions:
+
+  * ``PyArena_New()``
+  * ``PyArena_Free()``
+  * ``PyArena_Malloc()``
+  * ``PyArena_AddPyObject()``
+
+  These functions were undocumented, excluded from the limited C API, and were
+  only used internally by the compiler.
+  (Contributed by Victor Stinner in :issue:`43244`.)

Include/Python.h

@@ -137,7 +137,6 @@
 #include "pystate.h"
 #include "context.h"
 
-#include "cpython/pyarena.h"
 #include "modsupport.h"
 #include "compile.h"
 #include "pythonrun.h"

Include/cpython/pyarena.h

@@ -1,64 +0,0 @@
-/* An arena-like memory interface for the compiler.
- */
-
-#ifndef Py_LIMITED_API
-#ifndef Py_PYARENA_H
-#define Py_PYARENA_H
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-  typedef struct _arena PyArena;
-
-  /* PyArena_New() and PyArena_Free() create a new arena and free it,
-     respectively.  Once an arena has been created, it can be used
-     to allocate memory via PyArena_Malloc().  Pointers to PyObject can
-     also be registered with the arena via PyArena_AddPyObject(), and the
-     arena will ensure that the PyObjects stay alive at least until
-     PyArena_Free() is called.  When an arena is freed, all the memory it
-     allocated is freed, the arena releases internal references to registered
-     PyObject*, and none of its pointers are valid.
-     XXX (tim) What does "none of its pointers are valid" mean?  Does it
-     XXX mean that pointers previously obtained via PyArena_Malloc() are
-     XXX no longer valid?  (That's clearly true, but not sure that's what
-     XXX the text is trying to say.)
-
-     PyArena_New() returns an arena pointer.  On error, it
-     returns a negative number and sets an exception.
-     XXX (tim):  Not true.  On error, PyArena_New() actually returns NULL,
-     XXX and looks like it may or may not set an exception (e.g., if the
-     XXX internal PyList_New(0) returns NULL, PyArena_New() passes that on
-     XXX and an exception is set; OTOH, if the internal
-     XXX block_new(DEFAULT_BLOCK_SIZE) returns NULL, that's passed on but
-     XXX an exception is not set in that case).
-  */
-  PyAPI_FUNC(PyArena *) PyArena_New(void);
-  PyAPI_FUNC(void) PyArena_Free(PyArena *);
-
-  /* Mostly like malloc(), return the address of a block of memory spanning
-   * `size` bytes, or return NULL (without setting an exception) if enough
-   * new memory can't be obtained.  Unlike malloc(0), PyArena_Malloc() with
-   * size=0 does not guarantee to return a unique pointer (the pointer
-   * returned may equal one or more other pointers obtained from
-   * PyArena_Malloc()).
-   * Note that pointers obtained via PyArena_Malloc() must never be passed to
-   * the system free() or realloc(), or to any of Python's similar memory-
-   * management functions.  PyArena_Malloc()-obtained pointers remain valid
-   * until PyArena_Free(ar) is called, at which point all pointers obtained
-   * from the arena `ar` become invalid simultaneously.
-   */
-  PyAPI_FUNC(void *) PyArena_Malloc(PyArena *, size_t size);
-
-  /* This routine isn't a proper arena allocation routine.  It takes
-   * a PyObject* and records it so that it can be DECREFed when the
-   * arena is freed.
-   */
-  PyAPI_FUNC(int) PyArena_AddPyObject(PyArena *, PyObject *);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* !Py_PYARENA_H */
-#endif /* Py_LIMITED_API */

Include/internal/pycore_asdl.h

@@ -8,6 +8,8 @@ extern "C" {
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
+#include "pycore_pyarena.h"       // _PyArena_Malloc()
+
 typedef PyObject * identifier;
 typedef PyObject * string;
 typedef PyObject * object;
@@ -65,7 +67,7 @@ asdl_ ## NAME ## _seq *_Py_asdl_ ## NAME ## _seq_new(Py_ssize_t size, PyArena *a
         return NULL; \
     } \
     n += sizeof(asdl_ ## NAME ## _seq); \
-    seq = (asdl_ ## NAME ## _seq *)PyArena_Malloc(arena, n); \
+    seq = (asdl_ ## NAME ## _seq *)_PyArena_Malloc(arena, n); \
     if (!seq) { \
         PyErr_NoMemory(); \
         return NULL; \

Include/internal/pycore_compile.h

@@ -8,7 +8,8 @@ extern "C" {
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
-struct _mod;   // Type defined in pycore_ast.h
+struct _arena;   // Type defined in pycore_pyarena.h
+struct _mod;     // Type defined in pycore_ast.h
 
 // Export the symbol for test_peg_generator (built as a library)
 PyAPI_FUNC(PyCodeObject*) _PyAST_Compile(
@@ -16,7 +17,7 @@ PyAPI_FUNC(PyCodeObject*) _PyAST_Compile(
     PyObject *filename,
     PyCompilerFlags *flags,
     int optimize,
-    PyArena *arena);
+    struct _arena *arena);
 extern PyFutureFeatures* _PyFuture_FromAST(
     struct _mod * mod,
     PyObject *filename
@@ -31,7 +32,7 @@ typedef struct {
 
 extern int _PyAST_Optimize(
     struct _mod *,
-    PyArena *arena,
+    struct _arena *arena,
     _PyASTOptimizeState *state);
 
 #ifdef __cplusplus

Include/internal/pycore_pyarena.h

@@ -0,0 +1,64 @@
+/* An arena-like memory interface for the compiler.
+ */
+
+#ifndef Py_INTERNAL_PYARENA_H
+#define Py_INTERNAL_PYARENA_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef Py_BUILD_CORE
+#  error "this header requires Py_BUILD_CORE define"
+#endif
+
+typedef struct _arena PyArena;
+
+/* _PyArena_New() and _PyArena_Free() create a new arena and free it,
+   respectively.  Once an arena has been created, it can be used
+   to allocate memory via _PyArena_Malloc().  Pointers to PyObject can
+   also be registered with the arena via _PyArena_AddPyObject(), and the
+   arena will ensure that the PyObjects stay alive at least until
+   _PyArena_Free() is called.  When an arena is freed, all the memory it
+   allocated is freed, the arena releases internal references to registered
+   PyObject*, and none of its pointers are valid.
+   XXX (tim) What does "none of its pointers are valid" mean?  Does it
+   XXX mean that pointers previously obtained via _PyArena_Malloc() are
+   XXX no longer valid?  (That's clearly true, but not sure that's what
+   XXX the text is trying to say.)
+
+   _PyArena_New() returns an arena pointer.  On error, it
+   returns a negative number and sets an exception.
+   XXX (tim):  Not true.  On error, _PyArena_New() actually returns NULL,
+   XXX and looks like it may or may not set an exception (e.g., if the
+   XXX internal PyList_New(0) returns NULL, _PyArena_New() passes that on
+   XXX and an exception is set; OTOH, if the internal
+   XXX block_new(DEFAULT_BLOCK_SIZE) returns NULL, that's passed on but
+   XXX an exception is not set in that case).
+*/
+PyAPI_FUNC(PyArena*) _PyArena_New(void);
+PyAPI_FUNC(void) _PyArena_Free(PyArena *);
+
+/* Mostly like malloc(), return the address of a block of memory spanning
+ * `size` bytes, or return NULL (without setting an exception) if enough
+ * new memory can't be obtained.  Unlike malloc(0), _PyArena_Malloc() with
+ * size=0 does not guarantee to return a unique pointer (the pointer
+ * returned may equal one or more other pointers obtained from
+ * _PyArena_Malloc()).
+ * Note that pointers obtained via _PyArena_Malloc() must never be passed to
+ * the system free() or realloc(), or to any of Python's similar memory-
+ * management functions.  _PyArena_Malloc()-obtained pointers remain valid
+ * until _PyArena_Free(ar) is called, at which point all pointers obtained
+ * from the arena `ar` become invalid simultaneously.
+ */
+PyAPI_FUNC(void*) _PyArena_Malloc(PyArena *, size_t size);
+
+/* This routine isn't a proper arena allocation routine.  It takes
+ * a PyObject* and records it so that it can be DECREFed when the
+ * arena is freed.
+ */
+PyAPI_FUNC(int) _PyArena_AddPyObject(PyArena *, PyObject *);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_INTERNAL_PYARENA_H */

Makefile.pre.in

@@ -1119,7 +1119,6 @@ PYTHON_HEADERS= \
 		$(srcdir)/Include/cpython/objimpl.h \
 		$(srcdir)/Include/cpython/odictobject.h \
 		$(srcdir)/Include/cpython/picklebufobject.h \
-		$(srcdir)/Include/cpython/pyarena.h \
 		$(srcdir)/Include/cpython/pyctype.h \
 		$(srcdir)/Include/cpython/pydebug.h \
 		$(srcdir)/Include/cpython/pyerrors.h \
@@ -1163,6 +1162,7 @@ PYTHON_HEADERS= \
 		$(srcdir)/Include/internal/pycore_long.h \
 		$(srcdir)/Include/internal/pycore_object.h \
 		$(srcdir)/Include/internal/pycore_pathconfig.h \
+		$(srcdir)/Include/internal/pycore_pyarena.h \
 		$(srcdir)/Include/internal/pycore_pyerrors.h \
 		$(srcdir)/Include/internal/pycore_pyhash.h \
 		$(srcdir)/Include/internal/pycore_pylifecycle.h \

Misc/NEWS.d/next/C API/2021-03-24-01-22-14.bpo-43244.31-97x.rst

@@ -0,0 +1,10 @@
+Remove the ``pyarena.h`` header file with functions:
+
+* ``PyArena_New()``
+* ``PyArena_Free()``
+* ``PyArena_Malloc()``
+* ``PyArena_AddPyObject()``
+
+These functions were undocumented, excluded from the limited C API, and were
+only used internally by the compiler.
+Patch by Victor Stinner.

PCbuild/pythoncore.vcxproj

@@ -201,6 +201,7 @@
     <ClInclude Include="..\Include\internal\pycore_long.h" />
     <ClInclude Include="..\Include\internal\pycore_object.h" />
     <ClInclude Include="..\Include\internal\pycore_pathconfig.h" />
+    <ClInclude Include="..\Include\internal\pycore_pyarena.h" />
     <ClInclude Include="..\Include\internal\pycore_pyerrors.h" />
     <ClInclude Include="..\Include\internal\pycore_pyhash.h" />
     <ClInclude Include="..\Include\internal\pycore_pylifecycle.h" />

PCbuild/pythoncore.vcxproj.filters

@@ -564,6 +564,9 @@
     <ClInclude Include="..\Include\internal\pycore_pathconfig.h">
       <Filter>Include\internal</Filter>
     </ClInclude>
+    <ClInclude Include="..\Include\internal\pycore_pyarena.h">
+      <Filter>Include\internal</Filter>
+    </ClInclude>
     <ClInclude Include="..\Include\internal\pycore_pyerrors.h">
       <Filter>Include\internal</Filter>
     </ClInclude>

Parser/asdl_c.py

@@ -362,7 +362,7 @@ class FunctionVisitor(PrototypeVisitor):
                 emit('return NULL;', 2)
                 emit('}', 1)
 
-        emit("p = (%s)PyArena_Malloc(arena, sizeof(*p));" % ctype, 1);
+        emit("p = (%s)_PyArena_Malloc(arena, sizeof(*p));" % ctype, 1);
         emit("if (!p)", 1)
         emit("return NULL;", 2)
         if union:
@@ -946,7 +946,7 @@ static int obj2ast_object(struct ast_state *Py_UNUSED(state), PyObject* obj, PyO
     if (obj == Py_None)
         obj = NULL;
     if (obj) {
-        if (PyArena_AddPyObject(arena, obj) < 0) {
+        if (_PyArena_AddPyObject(arena, obj) < 0) {
             *out = NULL;
             return -1;
         }
@@ -958,7 +958,7 @@ static int obj2ast_object(struct ast_state *Py_UNUSED(state), PyObject* obj, PyO
 
 static int obj2ast_constant(struct ast_state *Py_UNUSED(state), PyObject* obj, PyObject** out, PyArena* arena)
 {
-    if (PyArena_AddPyObject(arena, obj) < 0) {
+    if (_PyArena_AddPyObject(arena, obj) < 0) {
         *out = NULL;
         return -1;
     }

Parser/pegen.c

@@ -13,7 +13,7 @@ _PyPegen_new_type_comment(Parser *p, char *s)
     if (res == NULL) {
         return NULL;
     }
-    if (PyArena_AddPyObject(p->arena, res) < 0) {
+    if (_PyArena_AddPyObject(p->arena, res) < 0) {
         Py_DECREF(res);
         return NULL;
     }
@@ -121,7 +121,7 @@ _PyPegen_new_identifier(Parser *p, char *n)
         id = id2;
     }
     PyUnicode_InternInPlace(&id);
-    if (PyArena_AddPyObject(p->arena, id) < 0)
+    if (_PyArena_AddPyObject(p->arena, id) < 0)
     {
         Py_DECREF(id);
         goto error;
@@ -526,7 +526,7 @@ int
 _PyPegen_insert_memo(Parser *p, int mark, int type, void *node)
 {
     // Insert in front
-    Memo *m = PyArena_Malloc(p->arena, sizeof(Memo));
+    Memo *m = _PyArena_Malloc(p->arena, sizeof(Memo));
     if (m == NULL) {
         return -1;
     }
@@ -690,7 +690,7 @@ _PyPegen_fill_token(Parser *p)
     if (t->bytes == NULL) {
         return -1;
     }
-    PyArena_AddPyObject(p->arena, t->bytes);
+    _PyArena_AddPyObject(p->arena, t->bytes);
 
     int lineno = type == STRING ? p->tok->first_lineno : p->tok->lineno;
     const char *line_start = type == STRING ? p->tok->multi_line_start : p->tok->line_start;
@@ -1029,7 +1029,7 @@ _PyPegen_number_token(Parser *p)
         return NULL;
     }
 
-    if (PyArena_AddPyObject(p->arena, c) < 0) {
+    if (_PyArena_AddPyObject(p->arena, c) < 0) {
         Py_DECREF(c);
         p->error_indicator = 1;
         return NULL;
@@ -1509,7 +1509,7 @@ _PyPegen_join_names_with_dot(Parser *p, expr_ty first_name, expr_ty second_name)
         return NULL;
     }
     PyUnicode_InternInPlace(&uni);
-    if (PyArena_AddPyObject(p->arena, uni) < 0) {
+    if (_PyArena_AddPyObject(p->arena, uni) < 0) {
         Py_DECREF(uni);
         return NULL;
     }
@@ -1547,7 +1547,7 @@ _PyPegen_alias_for_star(Parser *p)
     if (!str) {
         return NULL;
     }
-    if (PyArena_AddPyObject(p->arena, str) < 0) {
+    if (_PyArena_AddPyObject(p->arena, str) < 0) {
         Py_DECREF(str);
         return NULL;
     }
@@ -1577,7 +1577,7 @@ CmpopExprPair *
 _PyPegen_cmpop_expr_pair(Parser *p, cmpop_ty cmpop, expr_ty expr)
 {
     assert(expr != NULL);
-    CmpopExprPair *a = PyArena_Malloc(p->arena, sizeof(CmpopExprPair));
+    CmpopExprPair *a = _PyArena_Malloc(p->arena, sizeof(CmpopExprPair));
     if (!a) {
         return NULL;
     }
@@ -1718,7 +1718,7 @@ _PyPegen_set_expr_context(Parser *p, expr_ty expr, expr_context_ty ctx)
 KeyValuePair *
 _PyPegen_key_value_pair(Parser *p, expr_ty key, expr_ty value)
 {
-    KeyValuePair *a = PyArena_Malloc(p->arena, sizeof(KeyValuePair));
+    KeyValuePair *a = _PyArena_Malloc(p->arena, sizeof(KeyValuePair));
     if (!a) {
         return NULL;
     }
@@ -1763,7 +1763,7 @@ _PyPegen_get_values(Parser *p, asdl_seq *seq)
 NameDefaultPair *
 _PyPegen_name_default_pair(Parser *p, arg_ty arg, expr_ty value, Token *tc)
 {
-    NameDefaultPair *a = PyArena_Malloc(p->arena, sizeof(NameDefaultPair));
+    NameDefaultPair *a = _PyArena_Malloc(p->arena, sizeof(NameDefaultPair));
     if (!a) {
         return NULL;
     }
@@ -1776,7 +1776,7 @@ _PyPegen_name_default_pair(Parser *p, arg_ty arg, expr_ty value, Token *tc)
 SlashWithDefault *
 _PyPegen_slash_with_default(Parser *p, asdl_arg_seq *plain_names, asdl_seq *names_with_defaults)
 {
-    SlashWithDefault *a = PyArena_Malloc(p->arena, sizeof(SlashWithDefault));
+    SlashWithDefault *a = _PyArena_Malloc(p->arena, sizeof(SlashWithDefault));
     if (!a) {
         return NULL;
     }
@@ -1789,7 +1789,7 @@ _PyPegen_slash_with_default(Parser *p, asdl_arg_seq *plain_names, asdl_seq *name
 StarEtc *
 _PyPegen_star_etc(Parser *p, arg_ty vararg, asdl_seq *kwonlyargs, arg_ty kwarg)
 {
-    StarEtc *a = PyArena_Malloc(p->arena, sizeof(StarEtc));
+    StarEtc *a = _PyArena_Malloc(p->arena, sizeof(StarEtc));
     if (!a) {
         return NULL;
     }
@@ -2025,7 +2025,7 @@ _PyPegen_empty_arguments(Parser *p)
 AugOperator *
 _PyPegen_augoperator(Parser *p, operator_ty kind)
 {
-    AugOperator *a = PyArena_Malloc(p->arena, sizeof(AugOperator));
+    AugOperator *a = _PyArena_Malloc(p->arena, sizeof(AugOperator));
     if (!a) {
         return NULL;
     }
@@ -2070,7 +2070,7 @@ _PyPegen_class_def_decorators(Parser *p, asdl_expr_seq *decorators, stmt_ty clas
 KeywordOrStarred *
 _PyPegen_keyword_or_starred(Parser *p, void *element, int is_keyword)
 {
-    KeywordOrStarred *a = PyArena_Malloc(p->arena, sizeof(KeywordOrStarred));
+    KeywordOrStarred *a = _PyArena_Malloc(p->arena, sizeof(KeywordOrStarred));
     if (!a) {
         return NULL;
     }
@@ -2211,7 +2211,7 @@ _PyPegen_concatenate_strings(Parser *p, asdl_seq *strings)
     }
 
     if (bytesmode) {
-        if (PyArena_AddPyObject(p->arena, bytes_str) < 0) {
+        if (_PyArena_AddPyObject(p->arena, bytes_str) < 0) {
             goto error;
         }
         return Constant(bytes_str, NULL, first->lineno, first->col_offset, last->end_lineno,

Parser/string_parser.c

@@ -1031,7 +1031,7 @@ make_str_node_and_del(Parser *p, PyObject **str, Token* first_token, Token *last
     PyObject *kind = NULL;
     *str = NULL;
     assert(PyUnicode_CheckExact(s));
-    if (PyArena_AddPyObject(p->arena, s) < 0) {
+    if (_PyArena_AddPyObject(p->arena, s) < 0) {
         Py_DECREF(s);
         return NULL;
     }

Python/Python-ast.c

@@ -961,7 +961,7 @@ static int obj2ast_object(struct ast_state *Py_UNUSED(state), PyObject* obj, PyO
     if (obj == Py_None)
         obj = NULL;
     if (obj) {
-        if (PyArena_AddPyObject(arena, obj) < 0) {
+        if (_PyArena_AddPyObject(arena, obj) < 0) {
             *out = NULL;
             return -1;
         }
@@ -973,7 +973,7 @@ static int obj2ast_object(struct ast_state *Py_UNUSED(state), PyObject* obj, PyO
 
 static int obj2ast_constant(struct ast_state *Py_UNUSED(state), PyObject* obj, PyObject** out, PyArena* arena)
 {
-    if (PyArena_AddPyObject(arena, obj) < 0) {
+    if (_PyArena_AddPyObject(arena, obj) < 0) {
         *out = NULL;
         return -1;
     }
@@ -1787,7 +1787,7 @@ Module(asdl_stmt_seq * body, asdl_type_ignore_seq * type_ignores, PyArena
        *arena)
 {
     mod_ty p;
-    p = (mod_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (mod_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Module_kind;
@@ -1800,7 +1800,7 @@ mod_ty
 Interactive(asdl_stmt_seq * body, PyArena *arena)
 {
     mod_ty p;
-    p = (mod_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (mod_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Interactive_kind;
@@ -1817,7 +1817,7 @@ Expression(expr_ty body, PyArena *arena)
                         "field 'body' is required for Expression");
         return NULL;
     }
-    p = (mod_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (mod_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Expression_kind;
@@ -1834,7 +1834,7 @@ FunctionType(asdl_expr_seq * argtypes, expr_ty returns, PyArena *arena)
                         "field 'returns' is required for FunctionType");
         return NULL;
     }
-    p = (mod_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (mod_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = FunctionType_kind;
@@ -1860,7 +1860,7 @@ FunctionDef(identifier name, arguments_ty args, asdl_stmt_seq * body,
                         "field 'args' is required for FunctionDef");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = FunctionDef_kind;
@@ -1894,7 +1894,7 @@ AsyncFunctionDef(identifier name, arguments_ty args, asdl_stmt_seq * body,
                         "field 'args' is required for AsyncFunctionDef");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = AsyncFunctionDef_kind;
@@ -1922,7 +1922,7 @@ ClassDef(identifier name, asdl_expr_seq * bases, asdl_keyword_seq * keywords,
                         "field 'name' is required for ClassDef");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = ClassDef_kind;
@@ -1943,7 +1943,7 @@ Return(expr_ty value, int lineno, int col_offset, int end_lineno, int
        end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Return_kind;
@@ -1960,7 +1960,7 @@ Delete(asdl_expr_seq * targets, int lineno, int col_offset, int end_lineno, int
        end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Delete_kind;
@@ -1982,7 +1982,7 @@ Assign(asdl_expr_seq * targets, expr_ty value, string type_comment, int lineno,
                         "field 'value' is required for Assign");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Assign_kind;
@@ -2016,7 +2016,7 @@ AugAssign(expr_ty target, operator_ty op, expr_ty value, int lineno, int
                         "field 'value' is required for AugAssign");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = AugAssign_kind;
@@ -2046,7 +2046,7 @@ AnnAssign(expr_ty target, expr_ty annotation, expr_ty value, int simple, int
                         "field 'annotation' is required for AnnAssign");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = AnnAssign_kind;
@@ -2077,7 +2077,7 @@ For(expr_ty target, expr_ty iter, asdl_stmt_seq * body, asdl_stmt_seq * orelse,
                         "field 'iter' is required for For");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = For_kind;
@@ -2109,7 +2109,7 @@ AsyncFor(expr_ty target, expr_ty iter, asdl_stmt_seq * body, asdl_stmt_seq *
                         "field 'iter' is required for AsyncFor");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = AsyncFor_kind;
@@ -2135,7 +2135,7 @@ While(expr_ty test, asdl_stmt_seq * body, asdl_stmt_seq * orelse, int lineno,
                         "field 'test' is required for While");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = While_kind;
@@ -2159,7 +2159,7 @@ If(expr_ty test, asdl_stmt_seq * body, asdl_stmt_seq * orelse, int lineno, int
                         "field 'test' is required for If");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = If_kind;
@@ -2178,7 +2178,7 @@ With(asdl_withitem_seq * items, asdl_stmt_seq * body, string type_comment, int
      lineno, int col_offset, int end_lineno, int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = With_kind;
@@ -2198,7 +2198,7 @@ AsyncWith(asdl_withitem_seq * items, asdl_stmt_seq * body, string type_comment,
           PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = AsyncWith_kind;
@@ -2222,7 +2222,7 @@ Match(expr_ty subject, asdl_match_case_seq * cases, int lineno, int col_offset,
                         "field 'subject' is required for Match");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Match_kind;
@@ -2240,7 +2240,7 @@ Raise(expr_ty exc, expr_ty cause, int lineno, int col_offset, int end_lineno,
       int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Raise_kind;
@@ -2259,7 +2259,7 @@ Try(asdl_stmt_seq * body, asdl_excepthandler_seq * handlers, asdl_stmt_seq *
     end_lineno, int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Try_kind;
@@ -2284,7 +2284,7 @@ Assert(expr_ty test, expr_ty msg, int lineno, int col_offset, int end_lineno,
                         "field 'test' is required for Assert");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Assert_kind;
@@ -2302,7 +2302,7 @@ Import(asdl_alias_seq * names, int lineno, int col_offset, int end_lineno, int
        end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Import_kind;
@@ -2319,7 +2319,7 @@ ImportFrom(identifier module, asdl_alias_seq * names, int level, int lineno,
            int col_offset, int end_lineno, int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = ImportFrom_kind;
@@ -2338,7 +2338,7 @@ Global(asdl_identifier_seq * names, int lineno, int col_offset, int end_lineno,
        int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Global_kind;
@@ -2355,7 +2355,7 @@ Nonlocal(asdl_identifier_seq * names, int lineno, int col_offset, int
          end_lineno, int end_col_offset, PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Nonlocal_kind;
@@ -2377,7 +2377,7 @@ Expr(expr_ty value, int lineno, int col_offset, int end_lineno, int
                         "field 'value' is required for Expr");
         return NULL;
     }
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Expr_kind;
@@ -2394,7 +2394,7 @@ Pass(int lineno, int col_offset, int end_lineno, int end_col_offset, PyArena
      *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Pass_kind;
@@ -2410,7 +2410,7 @@ Break(int lineno, int col_offset, int end_lineno, int end_col_offset, PyArena
       *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Break_kind;
@@ -2426,7 +2426,7 @@ Continue(int lineno, int col_offset, int end_lineno, int end_col_offset,
          PyArena *arena)
 {
     stmt_ty p;
-    p = (stmt_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (stmt_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Continue_kind;
@@ -2447,7 +2447,7 @@ BoolOp(boolop_ty op, asdl_expr_seq * values, int lineno, int col_offset, int
                         "field 'op' is required for BoolOp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = BoolOp_kind;
@@ -2475,7 +2475,7 @@ NamedExpr(expr_ty target, expr_ty value, int lineno, int col_offset, int
                         "field 'value' is required for NamedExpr");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = NamedExpr_kind;
@@ -2508,7 +2508,7 @@ BinOp(expr_ty left, operator_ty op, expr_ty right, int lineno, int col_offset,
                         "field 'right' is required for BinOp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = BinOp_kind;
@@ -2537,7 +2537,7 @@ UnaryOp(unaryop_ty op, expr_ty operand, int lineno, int col_offset, int
                         "field 'operand' is required for UnaryOp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = UnaryOp_kind;
@@ -2565,7 +2565,7 @@ Lambda(arguments_ty args, expr_ty body, int lineno, int col_offset, int
                         "field 'body' is required for Lambda");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Lambda_kind;
@@ -2598,7 +2598,7 @@ IfExp(expr_ty test, expr_ty body, expr_ty orelse, int lineno, int col_offset,
                         "field 'orelse' is required for IfExp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = IfExp_kind;
@@ -2617,7 +2617,7 @@ Dict(asdl_expr_seq * keys, asdl_expr_seq * values, int lineno, int col_offset,
      int end_lineno, int end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Dict_kind;
@@ -2635,7 +2635,7 @@ Set(asdl_expr_seq * elts, int lineno, int col_offset, int end_lineno, int
     end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Set_kind;
@@ -2657,7 +2657,7 @@ ListComp(expr_ty elt, asdl_comprehension_seq * generators, int lineno, int
                         "field 'elt' is required for ListComp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = ListComp_kind;
@@ -2680,7 +2680,7 @@ SetComp(expr_ty elt, asdl_comprehension_seq * generators, int lineno, int
                         "field 'elt' is required for SetComp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = SetComp_kind;
@@ -2709,7 +2709,7 @@ DictComp(expr_ty key, expr_ty value, asdl_comprehension_seq * generators, int
                         "field 'value' is required for DictComp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = DictComp_kind;
@@ -2733,7 +2733,7 @@ GeneratorExp(expr_ty elt, asdl_comprehension_seq * generators, int lineno, int
                         "field 'elt' is required for GeneratorExp");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = GeneratorExp_kind;
@@ -2756,7 +2756,7 @@ Await(expr_ty value, int lineno, int col_offset, int end_lineno, int
                         "field 'value' is required for Await");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Await_kind;
@@ -2773,7 +2773,7 @@ Yield(expr_ty value, int lineno, int col_offset, int end_lineno, int
       end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Yield_kind;
@@ -2795,7 +2795,7 @@ YieldFrom(expr_ty value, int lineno, int col_offset, int end_lineno, int
                         "field 'value' is required for YieldFrom");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = YieldFrom_kind;
@@ -2818,7 +2818,7 @@ Compare(expr_ty left, asdl_int_seq * ops, asdl_expr_seq * comparators, int
                         "field 'left' is required for Compare");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Compare_kind;
@@ -2842,7 +2842,7 @@ Call(expr_ty func, asdl_expr_seq * args, asdl_keyword_seq * keywords, int
                         "field 'func' is required for Call");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Call_kind;
@@ -2867,7 +2867,7 @@ FormattedValue(expr_ty value, int conversion, expr_ty format_spec, int lineno,
                         "field 'value' is required for FormattedValue");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = FormattedValue_kind;
@@ -2886,7 +2886,7 @@ JoinedStr(asdl_expr_seq * values, int lineno, int col_offset, int end_lineno,
           int end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = JoinedStr_kind;
@@ -2908,7 +2908,7 @@ Constant(constant value, string kind, int lineno, int col_offset, int
                         "field 'value' is required for Constant");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Constant_kind;
@@ -2941,7 +2941,7 @@ Attribute(expr_ty value, identifier attr, expr_context_ty ctx, int lineno, int
                         "field 'ctx' is required for Attribute");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Attribute_kind;
@@ -2975,7 +2975,7 @@ Subscript(expr_ty value, expr_ty slice, expr_context_ty ctx, int lineno, int
                         "field 'ctx' is required for Subscript");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Subscript_kind;
@@ -3004,7 +3004,7 @@ Starred(expr_ty value, expr_context_ty ctx, int lineno, int col_offset, int
                         "field 'ctx' is required for Starred");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Starred_kind;
@@ -3032,7 +3032,7 @@ Name(identifier id, expr_context_ty ctx, int lineno, int col_offset, int
                         "field 'ctx' is required for Name");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Name_kind;
@@ -3055,7 +3055,7 @@ List(asdl_expr_seq * elts, expr_context_ty ctx, int lineno, int col_offset, int
                         "field 'ctx' is required for List");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = List_kind;
@@ -3078,7 +3078,7 @@ Tuple(asdl_expr_seq * elts, expr_context_ty ctx, int lineno, int col_offset,
                         "field 'ctx' is required for Tuple");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Tuple_kind;
@@ -3096,7 +3096,7 @@ Slice(expr_ty lower, expr_ty upper, expr_ty step, int lineno, int col_offset,
       int end_lineno, int end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = Slice_kind;
@@ -3125,7 +3125,7 @@ MatchAs(expr_ty pattern, identifier name, int lineno, int col_offset, int
                         "field 'name' is required for MatchAs");
         return NULL;
     }
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = MatchAs_kind;
@@ -3143,7 +3143,7 @@ MatchOr(asdl_expr_seq * patterns, int lineno, int col_offset, int end_lineno,
         int end_col_offset, PyArena *arena)
 {
     expr_ty p;
-    p = (expr_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (expr_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = MatchOr_kind;
@@ -3170,7 +3170,7 @@ comprehension(expr_ty target, expr_ty iter, asdl_expr_seq * ifs, int is_async,
                         "field 'iter' is required for comprehension");
         return NULL;
     }
-    p = (comprehension_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (comprehension_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->target = target;
@@ -3186,7 +3186,7 @@ ExceptHandler(expr_ty type, identifier name, asdl_stmt_seq * body, int lineno,
               *arena)
 {
     excepthandler_ty p;
-    p = (excepthandler_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (excepthandler_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = ExceptHandler_kind;
@@ -3206,7 +3206,7 @@ arguments(asdl_arg_seq * posonlyargs, asdl_arg_seq * args, arg_ty vararg,
           asdl_expr_seq * defaults, PyArena *arena)
 {
     arguments_ty p;
-    p = (arguments_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (arguments_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->posonlyargs = posonlyargs;
@@ -3229,7 +3229,7 @@ arg(identifier arg, expr_ty annotation, string type_comment, int lineno, int
                         "field 'arg' is required for arg");
         return NULL;
     }
-    p = (arg_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (arg_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->arg = arg;
@@ -3252,7 +3252,7 @@ keyword(identifier arg, expr_ty value, int lineno, int col_offset, int
                         "field 'value' is required for keyword");
         return NULL;
     }
-    p = (keyword_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (keyword_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->arg = arg;
@@ -3273,7 +3273,7 @@ alias(identifier name, identifier asname, PyArena *arena)
                         "field 'name' is required for alias");
         return NULL;
     }
-    p = (alias_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (alias_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->name = name;
@@ -3290,7 +3290,7 @@ withitem(expr_ty context_expr, expr_ty optional_vars, PyArena *arena)
                         "field 'context_expr' is required for withitem");
         return NULL;
     }
-    p = (withitem_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (withitem_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->context_expr = context_expr;
@@ -3307,7 +3307,7 @@ match_case(expr_ty pattern, expr_ty guard, asdl_stmt_seq * body, PyArena *arena)
                         "field 'pattern' is required for match_case");
         return NULL;
     }
-    p = (match_case_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (match_case_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->pattern = pattern;
@@ -3325,7 +3325,7 @@ TypeIgnore(int lineno, string tag, PyArena *arena)
                         "field 'tag' is required for TypeIgnore");
         return NULL;
     }
-    p = (type_ignore_ty)PyArena_Malloc(arena, sizeof(*p));
+    p = (type_ignore_ty)_PyArena_Malloc(arena, sizeof(*p));
     if (!p)
         return NULL;
     p->kind = TypeIgnore_kind;

Python/ast_opt.c

@@ -16,7 +16,7 @@ make_const(expr_ty node, PyObject *val, PyArena *arena)
         PyErr_Clear();
         return 1;
     }
-    if (PyArena_AddPyObject(arena, val) < 0) {
+    if (_PyArena_AddPyObject(arena, val) < 0) {
         Py_DECREF(val);
         return 0;
     }

Python/bltinmodule.c

@@ -828,21 +828,21 @@ builtin_compile_impl(PyObject *module, PyObject *source, PyObject *filename,
             PyArena *arena;
             mod_ty mod;
 
-            arena = PyArena_New();
+            arena = _PyArena_New();
             if (arena == NULL)
                 goto error;
             mod = PyAST_obj2mod(source, arena, compile_mode);
             if (mod == NULL) {
-                PyArena_Free(arena);
+                _PyArena_Free(arena);
                 goto error;
             }
             if (!_PyAST_Validate(mod)) {
-                PyArena_Free(arena);
+                _PyArena_Free(arena);
                 goto error;
             }
             result = (PyObject*)_PyAST_Compile(mod, filename,
                                                &cf, optimize, arena);
-            PyArena_Free(arena);
+            _PyArena_Free(arena);
         }
         goto finally;
     }

Python/pyarena.c

@@ -1,4 +1,5 @@
 #include "Python.h"
+#include "pycore_pyarena.h"       // PyArena
 
 /* A simple arena block structure.
 
@@ -125,7 +126,7 @@ block_alloc(block *b, size_t size)
 }
 
 PyArena *
-PyArena_New()
+_PyArena_New(void)
 {
     PyArena* arena = (PyArena *)PyMem_Malloc(sizeof(PyArena));
     if (!arena)
@@ -154,7 +155,7 @@ PyArena_New()
 }
 
 void
-PyArena_Free(PyArena *arena)
+_PyArena_Free(PyArena *arena)
 {
     assert(arena);
 #if defined(Py_DEBUG)
@@ -177,7 +178,7 @@ PyArena_Free(PyArena *arena)
 }
 
 void *
-PyArena_Malloc(PyArena *arena, size_t size)
+_PyArena_Malloc(PyArena *arena, size_t size)
 {
     void *p = block_alloc(arena->a_cur, size);
     if (!p)
@@ -200,7 +201,7 @@ PyArena_Malloc(PyArena *arena, size_t size)
 }
 
 int
-PyArena_AddPyObject(PyArena *arena, PyObject *obj)
+_PyArena_AddPyObject(PyArena *arena, PyObject *obj)
 {
     int r = PyList_Append(arena->a_objects, obj);
     if (r >= 0) {

Python/pythonrun.c

@@ -247,7 +247,7 @@ PyRun_InteractiveOneObjectEx(FILE *fp, PyObject *filename,
             }
         }
     }
-    arena = PyArena_New();
+    arena = _PyArena_New();
     if (arena == NULL) {
         Py_XDECREF(v);
         Py_XDECREF(w);
@@ -262,7 +262,7 @@ PyRun_InteractiveOneObjectEx(FILE *fp, PyObject *filename,
     Py_XDECREF(w);
     Py_XDECREF(oenc);
     if (mod == NULL) {
-        PyArena_Free(arena);
+        _PyArena_Free(arena);
         if (errcode == E_EOF) {
             PyErr_Clear();
             return E_EOF;
@@ -271,12 +271,12 @@ PyRun_InteractiveOneObjectEx(FILE *fp, PyObject *filename,
     }
     m = PyImport_AddModuleObject(mod_name);
     if (m == NULL) {
-        PyArena_Free(arena);
+        _PyArena_Free(arena);
         return -1;
     }
     d = PyModule_GetDict(m);
     v = run_mod(mod, filename, d, d, flags, arena);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     if (v == NULL) {
         return -1;
     }
@@ -1099,7 +1099,7 @@ PyRun_StringFlags(const char *str, int start, PyObject *globals,
     if (filename == NULL)
         return NULL;
 
-    arena = PyArena_New();
+    arena = _PyArena_New();
     if (arena == NULL)
         return NULL;
 
@@ -1107,7 +1107,7 @@ PyRun_StringFlags(const char *str, int start, PyObject *globals,
 
     if (mod != NULL)
         ret = run_mod(mod, filename, globals, locals, flags, arena);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     return ret;
 }
 
@@ -1116,7 +1116,7 @@ static PyObject *
 pyrun_file(FILE *fp, PyObject *filename, int start, PyObject *globals,
            PyObject *locals, int closeit, PyCompilerFlags *flags)
 {
-    PyArena *arena = PyArena_New();
+    PyArena *arena = _PyArena_New();
     if (arena == NULL) {
         return NULL;
     }
@@ -1136,7 +1136,7 @@ pyrun_file(FILE *fp, PyObject *filename, int start, PyObject *globals,
     else {
         ret = NULL;
     }
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
 
     return ret;
 }
@@ -1289,22 +1289,22 @@ Py_CompileStringObject(const char *str, PyObject *filename, int start,
 {
     PyCodeObject *co;
     mod_ty mod;
-    PyArena *arena = PyArena_New();
+    PyArena *arena = _PyArena_New();
     if (arena == NULL)
         return NULL;
 
     mod = _PyParser_ASTFromString(str, filename, start, flags, arena);
     if (mod == NULL) {
-        PyArena_Free(arena);
+        _PyArena_Free(arena);
         return NULL;
     }
     if (flags && (flags->cf_flags & PyCF_ONLY_AST)) {
         PyObject *result = PyAST_mod2obj(mod);
-        PyArena_Free(arena);
+        _PyArena_Free(arena);
         return result;
     }
     co = _PyAST_Compile(mod, filename, flags, optimize, arena);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     return (PyObject *)co;
 }
 

Python/symtable.c

@@ -1972,16 +1972,16 @@ _Py_SymtableStringObjectFlags(const char *str, PyObject *filename,
     mod_ty mod;
     PyArena *arena;
 
-    arena = PyArena_New();
+    arena = _PyArena_New();
     if (arena == NULL)
         return NULL;
 
     mod = _PyParser_ASTFromString(str, filename, start, flags, arena);
     if (mod == NULL) {
-        PyArena_Free(arena);
+        _PyArena_Free(arena);
         return NULL;
     }
     st = _PySymtable_Build(mod, filename, 0);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     return st;
 }

Tools/peg_generator/peg_extension/peg_extension.c

@@ -32,7 +32,7 @@ parse_file(PyObject *self, PyObject *args, PyObject *kwds)
         return PyErr_Format(PyExc_ValueError, "Bad mode, must be 0 <= mode <= 2");
     }
 
-    PyArena *arena = PyArena_New();
+    PyArena *arena = _PyArena_New();
     if (arena == NULL) {
         return NULL;
     }
@@ -63,7 +63,7 @@ parse_file(PyObject *self, PyObject *args, PyObject *kwds)
 
 error:
     Py_XDECREF(filename_ob);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     return result;
 }
 
@@ -80,7 +80,7 @@ parse_string(PyObject *self, PyObject *args, PyObject *kwds)
         return PyErr_Format(PyExc_ValueError, "Bad mode, must be 0 <= mode <= 2");
     }
 
-    PyArena *arena = PyArena_New();
+    PyArena *arena = _PyArena_New();
     if (arena == NULL) {
         return NULL;
     }
@@ -102,7 +102,7 @@ parse_string(PyObject *self, PyObject *args, PyObject *kwds)
 
 error:
     Py_XDECREF(filename_ob);
-    PyArena_Free(arena);
+    _PyArena_Free(arena);
     return result;
 }