Sharing mutable (or non-immortal) objects between interpreters is generally not safe. We can work around that but not easily.
There are two restrictions that are critical for objects that break interpreter isolation.
The first is that the object's state be guarded by a global lock. For now the GIL meets this requirement, but a granular global lock is needed once we have a per-interpreter GIL.
The second restriction is that the object (and, for a container, its items) be deallocated/resized only when the interpreter in which it was allocated is the current one. This is because every interpreter has (or will have, see gh-101660) its own object allocator. Deallocating an object with a different allocator can cause crashes.
The dict for the cache of module defs is completely internal, which simplifies what we have to do to meet those requirements. To do so, we do the following:
* add a mechanism for re-using a temporary thread state tied to the main interpreter in an arbitrary thread
* add _PyRuntime.imports.extensions.main_tstate`
* add _PyThreadState_InitDetached() and _PyThreadState_ClearDetached() (pystate.c)
* add _PyThreadState_BindDetached() and _PyThreadState_UnbindDetached() (pystate.c)
* make sure the cache dict (_PyRuntime.imports.extensions.dict) and its items are all owned by the main interpreter)
* add a placeholder using for a granular global lock
Note that the cache is only used for legacy extension modules and not for multi-phase init modules.
https://github.com/python/cpython/issues/100227
On content update, builds `python` and the docs. Also adds a Dockerfile that should include everything but autoconf 2.69 that's necessary to build CPython and the entire stdlib on Fedora.
Co-authored-by: Ronald Oussoren <ronaldoussoren@mac.com>
Co-authored-by: Dusty Phillips <dusty@phillips.codes>
We can revisit the options for keeping it global later, if desired. For now the approach seems quite complex, so we've gone with the simpler isolation solution in the meantime.
https://github.com/python/cpython/issues/100227
There are some warnings if build python via clang:
Parser/pegen.c:812:31: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
_PyPegen_clear_memo_statistics()
^
void
Parser/pegen.c:820:29: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
_PyPegen_get_memo_statistics()
^
void
Fix it to make clang happy.
Signed-off-by: Chenxi Mao <chenxi.mao@suse.com>
This reverts commit 87be8d9.
This approach to keeping the interned strings safe is turning out to be too complex for my taste (due to obmalloc isolation). For now I'm going with the simpler solution, making the dict per-interpreter. We can revisit that later if we want a sharing solution.
This commit prefixes `__dataclass` to several things in the locals dict:
- Names like `_dflt_` (which cause trouble, see first test)
- Names like `_type_` (not known to be able to cause trouble)
- `_return_type` (not known to able to cause trouble)
- `_HAS_DEFAULT_FACTORY` (which causes trouble, see second test)
In addition, this removes `MISSING` from the locals dict. As far as I can tell, this wasn't needed even in the initial implementation of dataclasses.py (and tests on that version passed with it removed). This makes me wary :-)
This is basically a continuation of #96151, where fixing this was welcomed in https://github.com/python/cpython/pull/98143#issuecomment-1280306360
In PEM, we need to parse until error and then suppress `PEM_R_NO_START_LINE`, because PEM allows arbitrary leading and trailing data. DER, however, does not. Parsing until error and suppressing `ASN1_R_HEADER_TOO_LONG` doesn't quite work because that error also covers some cases that should be rejected.
Instead, check `BIO_eof` early and stop the loop that way.
Automerge-Triggered-By: GH:Yhg1s
Previously, this used to fail:
```py
from typing import *
T = TypeVar("T")
P = ParamSpec("P")
class X(Generic[P]):
f: Callable[P, int]
Y = X[[int, T]]
Z = Y[str]
```
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
This is effectively two changes. The first (the bulk of the change) is where we add _Py_AddToGlobalDict() (and _PyRuntime.cached_objects.main_tstate, etc.). The second (much smaller) change is where we update PyUnicode_InternInPlace() to use _Py_AddToGlobalDict() instead of calling PyDict_SetDefault() directly.
Basically, _Py_AddToGlobalDict() is a wrapper around PyDict_SetDefault() that should be used whenever we need to add a value to a runtime-global dict object (in the few cases where we are leaving the container global rather than moving it to PyInterpreterState, e.g. the interned strings dict). _Py_AddToGlobalDict() does all the necessary work to make sure the target global dict is shared safely between isolated interpreters. This is especially important as we move the obmalloc state to each interpreter (gh-101660), as well as, potentially, the GIL (PEP 684).
https://github.com/python/cpython/issues/100227
