cpython/Python/clinic
Petr Viktorin 6f1d448bc1
gh-113993: Allow interned strings to be mortal, and fix related issues (GH-120520)
* Add an InternalDocs file describing how interning should work and how to use it.

* Add internal functions to *explicitly* request what kind of interning is done:
  - `_PyUnicode_InternMortal`
  - `_PyUnicode_InternImmortal`
  - `_PyUnicode_InternStatic`

* Switch uses of `PyUnicode_InternInPlace` to those.

* Disallow using `_Py_SetImmortal` on strings directly.
  You should use `_PyUnicode_InternImmortal` instead:
  - Strings should be interned before immortalization, otherwise you're possibly
    interning a immortalizing copy.
  - `_Py_SetImmortal` doesn't handle the `SSTATE_INTERNED_MORTAL` to
    `SSTATE_INTERNED_IMMORTAL` update, and those flags can't be changed in
    backports, as they are now part of public API and version-specific ABI.

* Add private `_only_immortal` argument for `sys.getunicodeinternedsize`, used in refleak test machinery.

* Make sure the statically allocated string singletons are unique. This means these sets are now disjoint:
  - `_Py_ID`
  - `_Py_STR` (including the empty string)
  - one-character latin-1 singletons

  Now, when you intern a singleton, that exact singleton will be interned.

* Add a `_Py_LATIN1_CHR` macro, use it instead of `_Py_ID`/`_Py_STR` for one-character latin-1 singletons everywhere (including Clinic).

* Intern `_Py_STR` singletons at startup.

* For free-threaded builds, intern `_Py_LATIN1_CHR` singletons at startup.

* Beef up the tests. Cover internal details (marked with `@cpython_only`).

* Add lots of assertions

Co-Authored-By: Eric Snow <ericsnowcurrently@gmail.com>
2024-06-21 17:19:31 +02:00
..
Python-tokenize.c.h
_warnings.c.h
bltinmodule.c.h gh-105879: Add support for keyword arguments to eval and exec (#105885) 2024-05-02 08:55:29 -07:00
context.c.h
import.c.h
instruction_sequence.c.h gh-117680: make _PyInstructionSequence a PyObject and use it in tests (#117629) 2024-04-17 16:42:04 +01:00
instrumentation.c.h
marshal.c.h
sysmodule.c.h gh-113993: Allow interned strings to be mortal, and fix related issues (GH-120520) 2024-06-21 17:19:31 +02:00
traceback.c.h