bpo-46541: Replace core use of _Py_IDENTIFIER() with statically initialized global objects. (gh-30928)

We're no longer using _Py_IDENTIFIER() (or _Py_static_string()) in any core CPython code.  It is still used in a number of non-builtin stdlib modules.

The replacement is: PyUnicodeObject (not pointer) fields under _PyRuntimeState, statically initialized as part of _PyRuntime.  A new _Py_GET_GLOBAL_IDENTIFIER() macro facilitates lookup of the fields (along with _Py_GET_GLOBAL_STRING() for non-identifier strings).

https://bugs.python.org/issue46541#msg411799 explains the rationale for this change.

The core of the change is in:

* (new) Include/internal/pycore_global_strings.h - the declarations for the global strings, along with the macros
* Include/internal/pycore_runtime_init.h - added the static initializers for the global strings
* Include/internal/pycore_global_objects.h - where the struct in pycore_global_strings.h is hooked into _PyRuntimeState
* Tools/scripts/generate_global_objects.py - added generation of the global string declarations and static initializers

I've also added a --check flag to generate_global_objects.py (along with make check-global-objects) to check for unused global strings.  That check is added to the PR CI config.

The remainder of this change updates the core code to use _Py_GET_GLOBAL_IDENTIFIER() instead of _Py_IDENTIFIER() and the related _Py*Id functions (likewise for _Py_GET_GLOBAL_STRING() instead of _Py_static_string()).  This includes adding a few functions where there wasn't already an alternative to _Py*Id(), replacing the _Py_Identifier * parameter with PyObject *.

The following are not changed (yet):

* stop using _Py_IDENTIFIER() in the stdlib modules
* (maybe) get rid of _Py_IDENTIFIER(), etc. entirely -- this may not be doable as at least one package on PyPI using this (private) API
* (maybe) intern the strings during runtime init

https://bugs.python.org/issue46541
This commit is contained in:
Eric Snow 2022-02-08 13:39:07 -07:00 committed by GitHub
parent c018d3037b
commit 81c72044a1
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GPG key ID: 4AEE18F83AFDEB23
108 changed files with 2282 additions and 1573 deletions

View file

@ -22,11 +22,12 @@
# include "pycore_bitutils.h" // _Py_popcount32()
#endif
#include "pycore_call.h" // _PyObject_CallNoArgs()
#include "pycore_fileutils.h" // _Py_closerange()
#include "pycore_moduleobject.h" // _PyModule_GetState()
#include "pycore_ceval.h" // _PyEval_ReInitThreads()
#include "pycore_fileutils.h" // _Py_closerange()
#include "pycore_import.h" // _PyImport_ReInitLock()
#include "pycore_initconfig.h" // _PyStatus_EXCEPTION()
#include "pycore_moduleobject.h" // _PyModule_GetState()
#include "pycore_object.h" // _PyObject_LookupSpecial()
#include "pycore_pystate.h" // _PyInterpreterState_GET()
#include "structmember.h" // PyMemberDef
@ -323,8 +324,6 @@ corresponding Unix manual entries for more information on calls.");
# endif /* _MSC_VER */
#endif /* ! __WATCOMC__ || __QNX__ */
_Py_IDENTIFIER(__fspath__);
/*[clinic input]
# one of the few times we lie about this name!
module os
@ -1159,7 +1158,7 @@ path_converter(PyObject *o, void *p)
/* Inline PyOS_FSPath() for better error messages. */
PyObject *func, *res;
func = _PyObject_LookupSpecial(o, &PyId___fspath__);
func = _PyObject_LookupSpecial(o, &_Py_ID(__fspath__));
if (NULL == func) {
goto error_format;
}
@ -14437,7 +14436,7 @@ PyOS_FSPath(PyObject *path)
return path;
}
func = _PyObject_LookupSpecial(path, &PyId___fspath__);
func = _PyObject_LookupSpecial(path, &_Py_ID(__fspath__));
if (NULL == func) {
return PyErr_Format(PyExc_TypeError,
"expected str, bytes or os.PathLike object, "