Enforcing (optionally) the restriction set by PEP 489 makes sense. Furthermore, this sets the stage for a potential restriction related to a per-interpreter GIL.
This change includes the following:
* add tests for extension module subinterpreter compatibility
* add _PyInterpreterConfig.check_multi_interp_extensions
* add Py_RTFLAGS_MULTI_INTERP_EXTENSIONS
* add _PyImport_CheckSubinterpIncompatibleExtensionAllowed()
* fail iff the module does not implement multi-phase init and the current interpreter is configured to check
https://github.com/python/cpython/issues/98627
This change is almost entirely moving code around and hiding import state behind internal API. We introduce no changes to behavior, nor to non-internal API. (Since there was already going to be a lot of churn, I took this as an opportunity to re-organize import.c into topically-grouped sections of code.) The motivation is to simplify a number of upcoming changes.
Specific changes:
* move existing import-related code to import.c, wherever possible
* add internal API for interacting with import state (both global and per-interpreter)
* use only API outside of import.c (to limit churn there when changing the location, etc.)
* consolidate the import-related state of PyInterpreterState into a single struct field (this changes layout slightly)
* add macros for import state in import.c (to simplify changing the location)
* group code in import.c into sections
*remove _PyState_AddModule()
https://github.com/python/cpython/issues/101758
The new test exercises the most important variants for single-phase init extension modules. We also add some explanation about those variants to import.c.
https://github.com/python/cpython/issues/101758
* Write output and metadata in a single run
This halves the time to run the cases generator
(most of the time goes into parsing the input).
* Declare or define opcode metadata based on NEED_OPCODE_TABLES
* Use generated metadata for stack_effect()
* compile.o depends on opcode_metadata.h
* Return -1 from _PyOpcode_num_popped/pushed for unknown opcode
* Make sure that the current exception is always normalized.
* Remove redundant type and traceback fields for the current exception.
* Add new API functions: PyErr_GetRaisedException, PyErr_SetRaisedException
* Add new API functions: PyException_GetArgs, PyException_SetArgs
New generator feature: Generate useful glue for output arrays, so you can just write values to the output array (no bounds checking). Rewrote UNPACK_SEQUENCE_TWO_TUPLE to use this, and also UNPACK_SEQUENCE_{TUPLE,LIST}.
The GILState API (PEP 311) implementation from 2003 made the assumption that only one thread state would ever be used for any given OS thread, explicitly disregarding the case of subinterpreters. However, PyThreadState_Swap() still facilitated switching between subinterpreters, meaning the "current" thread state (holding the GIL), and the GILState thread state could end up out of sync, causing problems (including crashes).
This change addresses the issue by keeping the two in sync in PyThreadState_Swap(). I verified the fix against gh-99040.
Note that the other GILState-subinterpreter incompatibility (with autoInterpreterState) is not resolved here.
https://github.com/python/cpython/issues/59956
A PyThreadState can be in one of many states in its lifecycle, represented by some status value. Those statuses haven't been particularly clear, so we're addressing that here. Specifically:
* made the distinct lifecycle statuses clear on PyThreadState
* identified expectations of how various lifecycle-related functions relate to status
* noted the various places where those expectations don't match the actual behavior
At some point we'll need to address the mismatches.
(This change also includes some cleanup.)
https://github.com/python/cpython/issues/59956
`warnings.warn()` gains the ability to skip stack frames based on code
filename prefix rather than only a numeric `stacklevel=` via a new
`skip_file_prefixes=` keyword argument.
We've factored out a struct from the two PyThreadState fields. This accomplishes two things:
* make it clear that the trashcan-related code doesn't need any other parts of PyThreadState
* allows us to use the trashcan mechanism even when there isn't a "current" thread state
We still expect the caller to hold the GIL.
https://github.com/python/cpython/issues/59956
Eric Snow