- Unify `_Py_ext_module_loader_info_init*` functions. The “core” one was entirely unused, and the difference between “builtin” and “extension” can be expressed in arguments.
- Consolidate getting & checking the module name from spec. (This improves error message wording for `imp.create_builtin` with empty name.)
- Allow non-ASCII names.
Core modules (`sys` and `builtins`) still don't go through the routine.
Co-authored-by: Itamar Oren <itamarost@gmail.com>
Document that single-phase init modules are added to sys.modules by
the call itself (unlike multi-phase init modules), and that the spec
name identifies the module, so a later call with the same name and a
different init function reuses the cached module without calling the
new init function. Add regression tests for both behaviors.
Co-authored-by: Petr Viktorin <encukou@gmail.com>
A single-phase init function that creates its module using only the
last component of a dotted name (as pybind11 does for submodules) got
a module whose __name__ was the short name. Set the package context
while calling the init function, as the dynamic loader does, so the
module gets the full name from the spec.
If a command line option wants to exit Python, move this option
processing from PyConfig_Read() to Py_Main(). So
Py_InitializeFromInitConfig() and Py_InitializeFromConfig() can no
longer return an exit code.
Deprecate PyInitConfig_GetExitCode(), PyStatus_Exit(), and PyStatus_IsExit()
functions, and PyStatus.exitcode member.
Renumber getopt.c long options to start at 1, instead of 0.
Keep 4 variables in the stable ABI:
* Py_FileSystemDefaultEncodeErrors
* Py_FileSystemDefaultEncoding
* Py_HasFileSystemDefaultEncoding
* Py_UTF8Mode
Mark the 4 variables as ABI only in Misc/stable_abi.toml.
Remove Py_SetProgramName(), Py_SetPythonHome(), PySys_SetArgv() and
PySys_SetArgvEx() functions, deprecated since Python 3.11.
Mark the 4 functions as abi_only in stable_abi.toml.
PyConfig_Read() and _PyPreConfig_Read() no longer read global config
variables (such as Py_BytesWarningFlag). Instead, PyConfig_Read() now
copies PyPreConfig members (isolated, use_environment and dev_mode).
_PyPreConfig_Read() still reads the last global configuration
variable: Py_UTF8Mode.
No longer use deprecated Py_IgnoreEnvironmentFlag in Py_GETENV().
Instead, use PyConfig.use_environment when Python is initialized.
Modify also PySys_SetArgv() to use PyConfig.isolated when Python is
initialized.
* Fix Py_RunMain() to return an exit code, rather than calling
Py_Exit(), when running a script, a command, or the REPL.
* _PyRun_SimpleFile() now logs errors to stderr, for example if setting
__main__.__file__ fails.
* Add tests on Py_RunMain() exitcode.
* Rename functions:
* _PyRun_SimpleStringFlagsWithName() => _PyRun_SimpleString()
* _PyRun_SimpleFileObject() => _PyRun_SimpleFile()
* _PyRun_AnyFileObject() => _PyRun_AnyFile()
* _PyRun_InteractiveLoopObject() => _PyRun_InteractiveLoop()
* Change _PyRun_SimpleString(), _PyRun_SimpleFile(), _PyRun_AnyFile() and
_PyRun_InteractiveLoop() return type to PyObject*.
* pymain_repl() now displays the error if PySys_Audit() or
import _pyrepl failed.
* PyRun_SimpleFileExFlags() and PyRun_AnyFileExFlags() now log
PyUnicode_DecodeFSDefault() error. So these functions can no longer
return -1 with an exception set.
## Summary
- Move the `runtime->initialized = 1` store from before `site.py` import to the end of `init_interp_main()`, so `Py_IsInitialized()` only returns true after initialization has fully completed
- Access `initialized` and `core_initialized` through new inline accessors using acquire/release atomics, to also protect from data race undefined behavior
- `PySys_AddAuditHook()` now uses the accessor, so with the flag move it correctly skips audit hook invocation during all init phases (matching the documented "after runtime initialization" behavior) ... We could argue that running these earlier would be good even if the intent was never explicitly expressed, but that'd be its own issue.
## Motivation
`Py_IsInitialized()` returned 1 while `Py_InitializeEx()` was still running — specifically, before `site.py` had been imported. See https://github.com/PyO3/pyo3/issues/5900 where a second thread could acquire the GIL and start executing Python with an incomplete `sys.path` because `site.py` hadn't finished.
The flag was also a plain `int` with no atomic operations, making concurrent reads a C-standard data race, though unlikely to manifest.
## Regression test:
The added test properly fails on `main` with `ERROR: Py_IsInitialized() was true during site import`.
---
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The pymalloc huge page support had two problems. First, on
architectures where the default huge page size exceeds the arena
size (e.g. 32 MiB on PPC, 512 MiB on ARM64 with 64 KB base
pages), mmap with MAP_HUGETLB silently allocates a full huge page
even when the requested size is smaller. The subsequent munmap
with the original arena size then fails with EINVAL, permanently
leaking the entire huge page. Second, huge pages were always
attempted when compiled in, with no way to disable them at
runtime. On Linux, if the huge page pool is exhausted, page
faults including copy-on-write faults after fork deliver SIGBUS
and kill the process.
The arena allocator now queries the system huge page size from
/proc/meminfo and skips MAP_HUGETLB when the arena size is not a
multiple of it. Huge pages also now require explicit opt-in at
runtime via the PYTHON_PYMALLOC_HUGEPAGES environment variable,
which is read through PyConfig and respects -E and -I flags.
The config field pymalloc_hugepages is propagated to the runtime
allocators struct so the low-level arena allocator can check it
without calling getenv directly.
Switches over to a _Py_thread_local in place of autoTssKey, and also fixes a few other checks regarding PyGILState_Ensure after finalization.
Note that this doesn't fix concurrent use of PyGILState_Ensure with Py_Finalize; I'm pretty sure zapthreads doesn't work at all, and that needs to be fixed seperately.
Incidentally, this also fixed the warning not showing up if a subinterpreter wasn't
cleaned up via _interpreters.destroy. I had to update some of the tests as a result.
Remove _PyInterpreterState_GetConfigCopy() and
_PyInterpreterState_SetConfig() private functions. PEP 741 "Python
Configuration C API" added a better public C API: PyConfig_Get() and
PyConfig_Set().
- move the Py_Main documentation from the very high level API section
to the initialization and finalization section
- make it clear that it encapsulates a full Py_Initialize/Finalize
cycle of its own
- point out that exactly which settings will be read and applied
correctly when Py_Main is called after a separate runtime
initialization call is version dependent
- be explicit that Py_IsInitialized can be called prior to
initialization
- actually test that Py_IsInitialized can be called prior to
initialization
- flush stdout in the embedding tests that run code so it appears
in the expected order when running with "-vv"
- make "-vv" on the subinterpreter embedding tests less spammy
---------
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
Setting dev_mode to 1 in an isolated configuration now enables also
faulthandler.
Moreover, setting "module_search_paths" option with
PyInitConfig_SetStrList() now sets "module_search_paths_set" to 1.
Check that the current default heap is initialized in
`_mi_os_get_aligned_hint` and `mi_os_claim_huge_pages`.
The mimalloc function `_mi_os_get_aligned_hint` assumes that there is an
initialized default heap. This is true for our main thread, but not for
background threads. The problematic code path is usually called during
initialization (i.e., `Py_Initialize`), but it may also be called if the
program allocates large amounts of memory in total.
The crash only affected the free-threaded build.
The tests were only checking cases where the slot wrapper was present in the initial case. They were missing when the slot wrapper was added in the additional initializations. This fixes that.
sys.audit() now has assertions to check that the event argument is
not NULL and that the format argument does not use the "N" format.
Add tests on PySys_AuditTuple().
Statistics gathering is now off by default. Use the "-X pystats"
command line option or set the new PYTHONSTATS environment variable
to 1 to turn statistics gathering on at Python startup.
Statistics are no longer dumped at exit if statistics gathering was
off or statistics have been cleared.
Changes:
* Add PYTHONSTATS environment variable.
* sys._stats_dump() now returns False if statistics are not dumped
because they are all equal to zero.
* Add PyConfig._pystats member.
* Add tests on sys functions and on setting PyConfig._pystats to 1.
* Add Include/cpython/pystats.h and Include/internal/pycore_pystats.h
header files.
* Rename '_py_stats' variable to '_Py_stats'.
* Exclude Include/cpython/pystats.h from the Py_LIMITED_API.
* Move pystats.h include from object.h to Python.h.
* Add _Py_StatsOn() and _Py_StatsOff() functions. Remove
'_py_stats_struct' variable from the API: make it static in
specialize.c.
* Document API in Include/pystats.h and Include/cpython/pystats.h.
* Complete pystats documentation in Doc/using/configure.rst.
* Don't write "all zeros" stats: if _stats_off() and _stats_clear()
or _stats_dump() were called.
* _PyEval_Fini() now always call _Py_PrintSpecializationStats() which
does nothing if stats are all zeros.
Co-authored-by: Michael Droettboom <mdboom@gmail.com>
Remove the following old functions to configure the Python
initialization, deprecated in Python 3.11:
* PySys_AddWarnOptionUnicode()
* PySys_AddWarnOption()
* PySys_AddXOption()
* PySys_HasWarnOptions()
* PySys_SetArgvEx()
* PySys_SetArgv()
* PySys_SetPath()
* Py_SetPath()
* Py_SetProgramName()
* Py_SetPythonHome()
* Py_SetStandardStreamEncoding()
* _Py_SetProgramFullPath()
Most of these functions are kept in the stable ABI, except:
* Py_SetStandardStreamEncoding()
* _Py_SetProgramFullPath()
Update Doc/extending/embedding.rst and Doc/extending/extending.rst to
use the new PyConfig API.
_testembed.c:
* check_stdio_details() now sets stdio_encoding and stdio_errors
of PyConfig.
* Add definitions of functions removed from the API but kept in the
stable ABI.
* test_init_from_config() and test_init_read_set() now use
PyConfig_SetString() instead of PyConfig_SetBytesString().
Remove _Py_ClearStandardStreamEncoding() internal function.
