The Python C API contains multiple functions which are not exported with PyAPI_FUNC() and so are not usable.

Public functions:
---

void PyLineTable_InitAddressRange(const char *linetable, Py_ssize_t length, int firstlineno, PyCodeAddressRange *range);
int PyLineTable_NextAddressRange(PyCodeAddressRange *range);
int PyLineTable_PreviousAddressRange(PyCodeAddressRange *range);

=> Either make this functions private ("_Py" prefix) and move them to the internal C API, or add PyAPI_FUNC().

Private functions:
---

int _PyCode_InitAddressRange(PyCodeObject* co, PyCodeAddressRange *bounds);
int _PyCode_InitEndAddressRange(PyCodeObject* co, PyCodeAddressRange* bounds);

PyDictKeysObject *_PyDict_NewKeysForClass(void);
Py_ssize_t _PyDict_KeysSize(PyDictKeysObject *keys);
uint32_t _PyDictKeys_GetVersionForCurrentState(PyDictKeysObject *dictkeys);
Py_ssize_t _PyDictKeys_StringLookup(PyDictKeysObject* dictkeys, PyObject *key);

PyObject *_PyDict_Pop_KnownHash(PyObject *, PyObject *, Py_hash_t, PyObject *);
PyObject *_PyDict_FromKeys(PyObject *, PyObject *, PyObject *);
int _PyObjectDict_SetItem(PyTypeObject *tp, PyObject **dictptr, PyObject *name, PyObject *value);
PyObject *_PyDict_LoadGlobal(PyDictObject *, PyDictObject *, PyObject *);
Py_ssize_t _PyDict_GetItemHint(PyDictObject *, PyObject *, Py_ssize_t, PyObject **);

PyFrameObject* _PyFrame_New_NoTrack(struct _interpreter_frame *, int);
int PySignal_SetWakeupFd(int fd);
uint32_t _PyFunction_GetVersionForCurrentState(PyFunctionObject *func);
PyObject *_PyGen_yf(PyGenObject *);
PyObject *_PyCoro_GetAwaitableIter(PyObject *o);
PyObject *_PyAsyncGenValueWrapperNew(PyObject *);
void _PyArg_Fini(void);
int _Py_CheckPython3(void);

=> I suggest to move all these declarations to the internal C API.

Moreover, Include/moduleobject.h contains:
---

#ifdef Py_BUILD_CORE
extern int _PyModule_IsExtension(PyObject *obj);
#endif

IMO this declaration should be moved to the internal C API.

See also bpo-45201 about PySignal_SetWakeupFd().

Agree.

We should also review all recently added functions with PyAPI_FUNC(). If they are not intended to be public API, PyAPI_FUNC() should be removed and declarations moved.

Regarding these three functions:

void PyLineTable_InitAddressRange(const char *linetable, Py_ssize_t length, int firstlineno, PyCodeAddressRange *range);
int PyLineTable_NextAddressRange(PyCodeAddressRange *range);
int PyLineTable_PreviousAddressRange(PyCodeAddressRange *range);

They are explicitly not part of the C API (limited or otherwise): https://www.python.org/dev/peps/pep-0626/#out-of-process-debuggers-and-profilers

See also bpo-45431: [C API] Rename CFrame or hide it to only export names starting with Py.

New changeset 4a0c7a1 by Victor Stinner in branch 'main':
bpo-45316: Move private PyCode C API to internal C API (GH-31576)
4a0c7a1

New changeset 8ddbdd9 by Victor Stinner in branch 'main':
bpo-45316: Move private PyDict functions to internal C API (GH-31577)
8ddbdd9

New changeset 8f2a337 by Victor Stinner in branch 'main':
bpo-45316: Move private functions to internal C API (GH-31579)
8f2a337

New changeset f780d96 by Victor Stinner in branch 'main':
bpo-45316: Move _PyArg_Fini() to internal C API (GH-31580)
f780d96

Update: only two remaining functions are not exported by the public C API:

int PySignal_SetWakeupFd(int fd);
int _Py_CheckPython3(void);

Thanks for working on this, Victor.

@vstinner hello, I find #31576 cause the _opcode module to fail to compile (config --enable-pystats)

renaming "_opcode" since importing it failed: dlopen(/build/lib.macosx-12.1-arm64-3.11-pydebug/_opcode.cpython-311d-darwin.so, 0x0002): symbol not found in flat namespace '__Py_GetSpecializationStats'

Maybe this declaration should be written to another file

Please open a new issue for your build error. It's unrelated to this issue.

I close this issue. I don't know how to handle PySignal_SetWakeupFd() and _Py_CheckPython3().

Please open a new issue for your build error. It's unrelated to this issue.

Oh wait, I misunderstood the issue. You're right, it's a regression caused by commit 4a0c7a1. I wrote PR #92011 to fix it.

I didn't notice that this function is actually used by a C extension built as a shared library, but only for a special build.

Thanks

I wrote PR #92011 to fix it.

Merged. I close again the issue.

#89479 (comment)

How are you supposed to use these functions than?
If they're private functions, and their symbol isn't exported, how can I link to these functions?
For now I copy paste them, but what if they change?

How are you supposed to use these functions than? If they're private functions, and their symbol isn't exported, how can I link to these functions?

They are not public on purpose. If you consider that they should be public, please open a feature request (a new issue). This issue is now closed, it's a bad place to discuss it.