(see https://github.com/python/cpython/issues/98608)
This change does the following:
1. change the argument to a new `_PyInterpreterConfig` struct
2. rename the function to `_Py_NewInterpreterFromConfig()`, inspired by `Py_InitializeFromConfig()` (takes a `_PyInterpreterConfig` instead of `isolated_subinterpreter`)
3. split up the boolean `isolated_subinterpreter` into the corresponding multiple granular settings
* allow_fork
* allow_subprocess
* allow_threads
4. add `PyInterpreterState.feature_flags` to store those settings
5. add a function for checking if a feature is enabled on an opaque `PyInterpreterState *`
6. drop `PyConfig._isolated_interpreter`
The existing default (see `Py_NewInterpeter()` and `Py_Initialize*()`) allows fork, subprocess, and threads and the optional "isolated" interpreter (see the `_xxsubinterpreters` module) disables all three. None of that changes here; the defaults are preserved.
Note that the given `_PyInterpreterConfig` will not be used outside `_Py_NewInterpreterFromConfig()`, nor preserved. This contrasts with how `PyConfig` is currently preserved, used, and even modified outside `Py_InitializeFromConfig()`. I'd rather just avoid that mess from the start for `_PyInterpreterConfig`. We can preserve it later if we find an actual need.
This change allows us to follow up with a number of improvements (e.g. stop disallowing subprocess and support disallowing exec instead).
(Note that this PR adds "private" symbols. We'll probably make them public, and add docs, in a separate change.)
The definition of obj in the `Py_buffer` struct is as a PyObject*
ec091bd47e/Include/pybuffer.h (L22)
PyMemoryView_GET_BASE returns `.obj` - thus its return type
should be a PyObject* (or at least a void*). It definitely
doesn't return `Py_buffer`
It had to live as a global outside of PyConfig for stable ABI reasons in
the pre-3.12 backports.
This removes the `_Py_global_config_int_max_str_digits` and gets rid of
the equivalent field in the internal `struct _is PyInterpreterState` as
code can just use the existing nested config struct within that.
Adds tests to verify unique settings and configs in subinterpreters.
⚠️⚠️ Note for reviewers, hackers and fellow systems/low-level/compiler engineers ⚠️⚠️
If you have a lot of experience with this kind of shenanigans and want to improve the **first** version, **please make a PR against my branch** or **reach out by email** or **suggest code changes directly on GitHub**.
If you have any **refinements or optimizations** please, wait until the first version is merged before starting hacking or proposing those so we can keep this PR productive.
* gh-93503: Add APIs to set profiling and tracing functions in all threads in the C-API
* Use a separate API
* Fix NEWS entry
* Add locks around the loop
* Document ignoring exceptions
* Use the new APIs in the sys module
* Update docs
An unrecognized format character in PyUnicode_FromFormat() and
PyUnicode_FromFormatV() now sets a SystemError.
In previous versions it caused all the rest of the format string to be
copied as-is to the result string, and any extra arguments discarded.
* Store tp_weaklist on the interpreter state for static builtin types.
* Factor out _PyStaticType_GET_WEAKREFS_LISTPTR().
* Add _PyStaticType_ClearWeakRefs().
* Add a comment about how _PyStaticType_ClearWeakRefs() loops.
* Document the change.
* Update Doc/whatsnew/3.12.rst
* Fix a typo.