Commit Graph
17382 Commits
Author SHA1 Message Date
Jeong, YunWon b366369119 Run llvm-cov in release so coverage finishes under 6h
Debug+instrumented `-m test -u all` spent 5.5h on 41 tests. Use
--release, a 120s per-test timeout, and -j0. Bound the suite step
at 180 minutes so a hang still leaves time to report.

Assisted-by: Grok:4.6
2026-09-22 23:47:36 +09:00
dependabot[bot] 31bdfe50bd build(deps): bump codecov/codecov-action from 7.0.0 to 7.1.0
Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 7.0.0 to 7.1.0.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](https://github.com/codecov/codecov-action/compare/fb8b3582c8e4def4969c97caa2f19720cb33a72f...0b35c9ecc4f0529d0eb674914510c22f85b196b4)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-version: 7.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
2026-09-22 21:41:49 +09:00
dependabot[bot] ea4e51d52d build(deps): bump https://github.com/astral-sh/ruff-pre-commit (#8777)
Bumps [https://github.com/astral-sh/ruff-pre-commit](https://github.com/astral-sh/ruff-pre-commit) from v0.16.4 to 0.16.7.
- [Release notes](https://github.com/astral-sh/ruff-pre-commit/releases)
- [Commits](https://github.com/astral-sh/ruff-pre-commit/compare/v0.16.4...v0.16.7)

---
updated-dependencies:
- dependency-name: https://github.com/astral-sh/ruff-pre-commit
  dependency-version: 0.16.7
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 14:55:37 +09:00
Jeong, YunWon 979ea4c4dc host_env: export vsock, wasm socket, Darwin flags (#8779)
* host_env: export vsock, wasm socket, Darwin flags

Publish vsock/UDPLITE/SOL fallbacks, wasm socket and errno
constants, remaining BSD chflags, and S_IFDOOR/PORT/WHT.

Assisted-by: Claude

* stdlib: take vsock, wasm socket, Darwin flags from host_env

_socket, wasm _socket/_io/errno, _stat, and openssl alerts now
re-export the host_env names.

Assisted-by: Claude

* host_env: keep wasm socket/errno off emscripten

wasm32-unknown-emscripten is unix, so the stub modules must be
unknown-unknown (and WASI) only.

Assisted-by: Claude

* stdlib: match socket module_def cfg to the module

Assisted-by: Claude

* host_env: drop duplicate Windows SOL_UDP

The IANA fallback also compiled on Windows, colliding with the
WinSock definition.

Assisted-by: Claude
2026-09-22 14:55:16 +09:00
Jeong, YunWon eb1546ae08 posix: add os.forkpty so pty.spawn does not hang (#8782)
* posix: add os.forkpty

pty.fork prefers forkpty so a nested spawn is a new session with its
own controlling tty. The openpty+login_tty fallback hung the
jsontests collector.

Assisted-by: Claude

* select: rebuild fd sets after EINTR

select(2) updates the sets in place. Retrying an interrupted call
with empty sets and a NULL timeout blocks forever.

Assisted-by: Claude

* http.server: keep CGI off the body-read timeout

A millisecond handler timeout races the client thread writing the
request and is inherited across CGI fork, which RSTs the client
under load.

Assisted-by: Claude

* Revert "http.server: keep CGI off the body-read timeout"

Lib edits outside a CPython copy are not allowed.

Assisted-by: Claude

* host_env: note why forkpty is libc not nix

Assisted-by: Claude

* benches: run deepcopy 10x more iterations

Assisted-by: Claude
2026-09-22 14:54:46 +09:00
Jeong, YunWon f56bfc9a5c Show stdin traceback lines; omit StopIteration None args (#8778)
* Show stdin traceback lines; omit StopIteration None args

Register interactive <stdin> source in linecache so REPL
tracebacks include the source line and caret. Build
StopIteration with empty args when the value is None, and
wrap monitoring STOP_ITERATION the same way.

Unskip REPL stderr flush tests and pdb Flaky doctests.

Assisted-by: Grok:4.6

* Take &Py<PyCode> in register_code_in_linecache

Assisted-by: Grok:4.6

* Count Unknown closing braces in tokenize EOF check

`$` inside an f-string interpolation is TokenKind::Unknown, so
the matching `}` is Unknown rather than Rbrace and generate_tokens
raised TokenError. Also convert &Py<PyCode> to PyObjectRef
explicitly when registering linecache.

Assisted-by: Grok:4.6

* Unskip test_pdb.PdbTestCase.test_zipimport

The test now passes, so the expectedFailure is an unexpected
success under CI.

Assisted-by: Grok:4.6

* Park STW threads; poll sockets after timeout deadline

Check per-thread stop_requested in eval_breaker_tripped so
workers still park when another interpreter clears STOP_BIT.

Start socket timeout after the fd snapshot, and poll once with
timeout 0 when the deadline has already passed, so a readable
socket is not dropped as timed out.

Assisted-by: Grok:4.6
2026-09-22 14:53:52 +09:00
Jeong, YunWon 23fcb8d913 Format the README JIT example for ruff-format (#8785)
ruff-format 0.16.7 formats Python fences in Markdown and wants two
blank lines after a top-level function.

Assisted-by: Grok:4.6
2026-09-22 10:49:05 +09:00
dependabot[bot] e3fb1eaa8a build(deps): bump reviewdog/action-actionlint from 1.73.4 to 1.74.0 (#8774)
Bumps [reviewdog/action-actionlint](https://github.com/reviewdog/action-actionlint) from 1.73.4 to 1.74.0.
- [Release notes](https://github.com/reviewdog/action-actionlint/releases)
- [Commits](https://github.com/reviewdog/action-actionlint/compare/d290e336d5a743810aef4404f757dc862276d2ae...8b682e1e7e512151d73a6b9449cbff173846226e)

---
updated-dependencies:
- dependency-name: reviewdog/action-actionlint
  dependency-version: 1.74.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 10:14:13 +09:00
dependabot[bot] 854b5af434 build(deps): bump jiff in the jiff group across 1 directory (#8768)
Bumps the jiff group with 1 update in the / directory: [jiff](https://github.com/BurntSushi/jiff).


Updates `jiff` from 0.2.35 to 0.2.37
- [Release notes](https://github.com/BurntSushi/jiff/releases)
- [Changelog](https://github.com/BurntSushi/jiff/blob/jiff-static-0.2.37/CHANGELOG.md)
- [Commits](https://github.com/BurntSushi/jiff/compare/jiff-static-0.2.35...jiff-static-0.2.37)

---
updated-dependencies:
- dependency-name: jiff
  dependency-version: 0.2.37
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: jiff
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 09:49:54 +09:00
dependabot[bot] 28ba022056 build(deps): bump crossbeam-utils from 0.8.22 to 0.8.23 (#8770)
Bumps [crossbeam-utils](https://github.com/crossbeam-rs/crossbeam) from 0.8.22 to 0.8.23.
- [Release notes](https://github.com/crossbeam-rs/crossbeam/releases)
- [Changelog](https://github.com/crossbeam-rs/crossbeam/blob/main/CHANGELOG.md)
- [Commits](https://github.com/crossbeam-rs/crossbeam/compare/crossbeam-utils-0.8.22...crossbeam-utils-0.8.23)

---
updated-dependencies:
- dependency-name: crossbeam-utils
  dependency-version: 0.8.23
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 09:49:45 +09:00
dependabot[bot] 94298caaf2 build(deps): bump zlib-rs from 0.6.7 to 0.6.8 (#8772)
Bumps [zlib-rs](https://github.com/trifectatechfoundation/zlib-rs) from 0.6.7 to 0.6.8.
- [Release notes](https://github.com/trifectatechfoundation/zlib-rs/releases)
- [Changelog](https://github.com/trifectatechfoundation/zlib-rs/blob/main/docs/release.md)
- [Commits](https://github.com/trifectatechfoundation/zlib-rs/compare/v0.6.7...v0.6.8)

---
updated-dependencies:
- dependency-name: zlib-rs
  dependency-version: 0.6.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 09:26:04 +09:00
dependabot[bot] 0c5788150d build(deps): bump reviewdog/action-suggester from 1.24.3 to 1.25.0 (#8771)
Bumps [reviewdog/action-suggester](https://github.com/reviewdog/action-suggester) from 1.24.3 to 1.25.0.
- [Release notes](https://github.com/reviewdog/action-suggester/releases)
- [Commits](https://github.com/reviewdog/action-suggester/compare/2558ba17e65a9039e73764a73009fc05fef28a46...4553543bea739d9d503379d786148cfd561de5fa)

---
updated-dependencies:
- dependency-name: reviewdog/action-suggester
  dependency-version: 1.25.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 09:25:50 +09:00
dependabot[bot] 2116a6d38a build(deps): bump cranelift in the wasmtime group across 1 directory (#8769)
Bumps the wasmtime group with 1 update in the / directory: [cranelift](https://github.com/bytecodealliance/wasmtime).


Updates `cranelift` from 0.135.1 to 0.135.2
- [Release notes](https://github.com/bytecodealliance/wasmtime/releases)
- [Changelog](https://github.com/bytecodealliance/wasmtime/blob/main/RELEASES.md)
- [Commits](https://github.com/bytecodealliance/wasmtime/commits)

---
updated-dependencies:
- dependency-name: cranelift
  dependency-version: 0.135.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: wasmtime
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 09:25:41 +09:00
dependabot[bot] 81bd48c26c build(deps): bump zizmorcore/zizmor-action from 0.6.3 to 0.6.4 (#8773)
Bumps [zizmorcore/zizmor-action](https://github.com/zizmorcore/zizmor-action) from 0.6.3 to 0.6.4.
- [Release notes](https://github.com/zizmorcore/zizmor-action/releases)
- [Commits](https://github.com/zizmorcore/zizmor-action/compare/70fb788f84895a7701f5643d103d587e460b5c99...cc914d7f3750a2d13d75c7f184a1060aa0e9d482)

---
updated-dependencies:
- dependency-name: zizmorcore/zizmor-action
  dependency-version: 0.6.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 01:16:53 +09:00
dependabot[bot] 16998af53d build(deps): bump github/gh-aw/actions/setup from 0.88.2 to 0.89.14 (#8776)
Bumps [github/gh-aw/actions/setup](https://github.com/github/gh-aw) from 0.88.2 to 0.89.14.
- [Release notes](https://github.com/github/gh-aw/releases)
- [Changelog](https://github.com/github/gh-aw/blob/main/CHANGELOG.md)
- [Commits](https://github.com/github/gh-aw/compare/8e30bcd8897f5047051fa3971188e1dd4cdb23cf...97b9a7c376bb60bd7cbcf348a5a6349b52e266ff)

---
updated-dependencies:
- dependency-name: github/gh-aw/actions/setup
  dependency-version: 0.89.14
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-09-22 00:18:25 +09:00
Jeong, YunWon fe45a7a35f host_env: export ctypes, chflags, SIG_DFL (#8766)
* host_env: export ctypes, chflags, SIG_DFL

Publish ctypes FUNCFLAG/TYPEFLAG/DICTFLAG and CTYPES_MAX_ARGCOUNT,
BSD chflags bits libc does not bind, AT_FDCWD, and SIG_DFL/IGN/ERR.

Assisted-by: Claude

* stdlib: take ctypes, chflags, SIG_DFL from host_env

_ctypes, _stat, os.AT_FDCWD, and Windows SIG_DFL/IGN/ERR now re-export
the host_env names. Wasm keeps local SIG_* literals.

Assisted-by: Claude
2026-09-21 22:20:10 +09:00
Jeong, YunWon 8fda0eccee Fix fork-child SIGSEGV and yield-from throw() args (#8759)
* Unskip passing flaky CPython tests

Remove RUSTPYTHON skip overlays after Linux release repeats passed
for enum, threading, logging, subprocess, socket, int, re, strtod,
and regrtest cases.

Assisted-by: Grok:4.6

* Fix fork-child SIGSEGV and yield-from throw args

Forget JoinHandle of threads that did not survive fork instead
of dropping them. Zero-reinit the import lock and condvars in
the child rather than unlock/notify. Resume the world if
os.fork() fails.

Call a yield-from subiterator throw() without None fillers so
a 1-arg throw stays 1-arg.

Drop the stale Windows expectedFailure on logging queue config
and unskip test_reinit_tls_after_fork plus the asyncio
local_addr family test.

Assisted-by: Grok:4.6

* Restore import lock depth after fork; add WASI clock info

Zeroing IMP_LOCK in the child discarded its recursion count, so
imp.release_lock() raised and test_fork1 exited 1. Re-acquire the
saved depth, then drop the extra pre-fork hold.

Expose time.get_clock_info on WASI via clock_getres so test_int
Stopwatch can run.

Unskip lock_tests test_acquire_contended and test_thread_leak.

Assisted-by: Grok:4.6

* Honor chmod follow_symlinks=False via fchmodat

Linux chmod followed the symlink, so dangling links raised
FileNotFoundError instead of NotImplementedError. Use fchmodat
with AT_SYMLINK_NOFOLLOW and map ENOTSUP to NotImplementedError.

Unskip httpservers truncated Content-Length (CPython already
skips as root) and tempfile symlink-mode cleanup on Linux.

Assisted-by: Grok:4.6

* Unskip httplib local bad-hostname HTTPS test

The skip was leftover. With default ssl-rustls the test passes
under -W error on Linux.

Assisted-by: Grok:4.6

* Fix list cmp deadlock, wasm digit overflow, REPL prompt

Do not hold list/deque locks across item comparison callbacks.
Compute int-to-str digit bounds in u64 so the check cannot wrap
on wasm32. Snapshot set contents when list.extend copies a set.

For a non-TTY stdin, write the REPL prompt to stderr and read
lines from stdin. Flush stdout/stderr after each interactive
command. Set sys.ps1/ps2 to ">>> " and "... ".

Unskip list mutation compares, asyncio all_tasks race, importlib
deadlock/parallel/circular-import tests, and REPL stdout flush.

Assisted-by: Grok:4.6

* Avoid unnecessary u64 cast in int-to-str digit check

bits() is already u64, so `bits as u64` fails clippy
unnecessary_cast under -Dwarnings.

Assisted-by: Grok:4.6
2026-09-21 20:53:53 +09:00
Jeong, YunWon a46627a33c Give trampoline frames a unique non-Copy handle (#8762)
run_trampoline takes &mut again; the loop holds TrampolineIFrame so
two &mut InterpreterFrame cannot alias the same allocation.

Assisted-by: Grok:4.6
2026-09-21 20:48:45 +09:00
Jeong, YunWon 803520930a capi: add PyFrame_GetLocals, GetGlobals, GetBuiltins (#8761)
Wire the C-API getters to frame.f_locals, f_globals, and f_builtins,
and cover write-through vs snapshot locals in a capi test.

Assisted-by: Grok:4.6
2026-09-21 19:38:05 +09:00
Jeong, YunWon 7b018871a3 host_env: export remaining stdlib constants (#8760)
* host_env: export winsound, spawn, and remaining SSL_OP flags

Assisted-by: Claude

* stdlib: take winsound, nt spawn, and SSL_OP names from host_env

Assisted-by: Claude

* host_env: export ssl alerts, sysexits, socket extras

Assisted-by: Claude

* stdlib: take remaining host_env and common constants

Assisted-by: Claude

* Remove unused workspace exitcode dependency

Assisted-by: Claude

* host_env: export PROTO, access, reparse, wait flags

Assisted-by: Claude

* stdlib: take PROTO, access, reparse, wait from host_env

Assisted-by: Claude
2026-09-21 19:37:16 +09:00
Jeong, YunWon 53a906c916 Match settrace events, f_lineno jumps, and type dict lookup (#8758)
* Keep type dict keys and report current f_lasti

Snapshot the MRO during lookup so non-string keys can run __eq__,
skip subclass updates when set_bases is reentered, make module
__dict__ a readonly member, and forbid deleting exception __dict__.
f_lasti is the current opcode; line events skip NO_LOCATION units.

Assisted-by: Grok:grok-4.6

* Fire settrace call events from RESUME

PY_START/PY_RESUME become a 'call' event only at the first RESUME
of a frame activation, so lasti is the resume unit and f_trace_lines
is honored. Unskip passing TraceTestCase methods.

Assisted-by: Grok:grok-4.6

* Record what_event so f_lineno jumps match line traces

Store the current monitoring event while a trace callback
runs, reject jumps from call/return/exception, unwind tracer
errors in the traced frame, and fire call on PY_THROW.
Unskip JumpTestCase except the infinite-loop and five remaining xfails.

Assisted-by: Grok:grok-4.6

* Fire remaining settrace events from opcodes and jumps

Keep GET_ANEXT's iterator in mark_stacks, dispatch non-call
events through f_trace, fire PY_YIELD/PY_RETURN from the
opcodes, emit same-line LINE on backward jumps, and raise at
flattened call sites. Unskip the rest of test_sys_settrace.

Assisted-by: Grok:grok-4.6

* Fix trampoline raise panic and unxfail passing traces

Do not decode inline-cache units as opcodes when a flattened
call raises. Remove expectedFailure from test_trace and
test_regrtest coverage tests that now pass.

Assisted-by: Grok:grok-4.6

* Fire profile returns without a per-frame f_trace

setprofile must see PY_RETURN/PY_YIELD even when f_trace is unset.
Drop EXPECTED_FAILURE from the pdb doctest and unxfail
test_unfinished_generator.

Assisted-by: Grok:grok-4.6
2026-09-21 18:11:32 +09:00
Jeong, YunWon 617c4be5d9 host_env: export remaining Win32 exception and file constants (#8757)
* host_env: export remaining Win32 exception and file constants

Assisted-by: Claude

* _winapi: take COPY_FILE_DIRECTORY and FILE_TYPE_UNKNOWN from host_env

Assisted-by: Claude
2026-09-21 16:20:39 +09:00
Jeong, YunWon 54420c4471 Drop serial MP CI retries and killpg overlay (#8756)
Multiprocessing fork/spawn/forkserver now run in the main -j $CORES
CPython test job. Remove expectedFailureIf for os.killpg now that
killpg exists.

Assisted-by: Grok:4.6
2026-09-21 12:19:14 +09:00
Hanjeong Lee e189ca7923 Compare native signatures and docstrings in whats_left.py (#8751)
* Record a module's docstring mismatches on their own

They were only kept when the module also had missing items or signature
mismatches, so annotationlib, base64, ntpath and _ctypes reported none.
Whether a module counts as implemented still depends on missing items
and signatures alone.

Assisted-by: Claude Code:claude-opus-5

* Report a builtin type method that differs as a mismatch

A method whose signature or docstring differed was listed under
"builtin items" as if it were missing, with both extra_info dicts as the
reason. That section feeds the website's builtin_items.csv. Differences
now go to mismatched_items and mismatched_doc_items, keyed by type name,
like module items. Nothing reaches this path yet because builtin
signatures are still skipped; without this change, lifting that skip
turns the one "builtin items" line into 455.

Assisted-by: Claude Code:claude-opus-5

* Compare signatures and docstrings of native callables

extra_info() skipped anything inspect treats as builtin since cc2c46b1b
(#2410), when RustPython had no __text_signature__ for builtins. It has
one now, so --signature and --doc cover functions and methods written in
Rust. Modules with a mismatched signature go from 45 to 134, and 160 of
the 710 mismatched items are ones CPython itself cannot parse, which the
--signature listing already skips.

__builtins__ is no longer compared. inspect.signature() evals defaults in
the owning module's namespace and eval() adds __builtins__ there, so
CPython's builtins module gained one after list.index was inspected and
it showed up as missing.

Assisted-by: Claude Code:claude-opus-5

* Scan the members of native classes in each module

A module was only compared one level deep, so a native class counted as
present whatever its methods were. Classes a module owns and that are
not Python-defined are now opened too, and their own members are
compared as "Class.member": 438 classes and 4,833 members, 1,033 of
which have a signature --signature reports.

A class is native when it has no __firstlineno__, which a class
statement records, and no Python functions of its own, which rules out
namedtuple-style classes made by type(). BUILTIN_TYPES moves to module
level so the builtin types are not reported twice, an alias like
array.ArrayType is skipped, and CPython's __annotations_cache__ and
__vectorcalloffset__ are left out.

RustPython follows the CPython list instead of deciding again. A member
only inherited is listed as missing with "(inherited)", as builtin type
methods are. A class missing here, or implemented as something else such
as _sha3's hash functions, is reported by its own line only.

Assisted-by: Claude Code:claude-opus-5

* Report a module that exists but cannot be imported

dir_of_mod_or_error() ran dir() on the exception import_module() returns,
so a failed import looked like a module whose every item is missing:
sqlite3 alone filled 198 of those lines, and CPython's own _ios_support
was compared as a module holding ImportError's attributes. Returning the
exception reaches the "exists but not importable" line that was already
written for it, and drops 529 lines from "stdlib items".

Assisted-by: Claude Code:claude-opus-5

* Compare a module's own docstring

extra_info() reports a docstring for callables, and a module is not one,
so the __doc__ item both sides record was None and a module docstring
never counted as a mismatch. Reading it with getdoc(), the way a
callable's is read, brings 221 module docstrings into the comparison.
sys is the one that differs; base64 and imaplib differ here only
because their Lib copies track 3.14.7 while this run used 3.14.6.

Non-callables keep reporting None. getdoc() on a plain value answers
with its type's docstring, which would turn every string constant into
a mismatch.

Assisted-by: Claude Code:claude-opus-5

* Decide a member's ownership by the class dictionary

attr_is_not_inherited() compared the attribute's value with each base's.
That took an inherited classmethod for the class's own, since a bound
method compares unequal across classes, and dropped an own attribute
whose value matched a base's default None: 394 of CPython's in all,
ast.FunctionDef.returns among them. On the RustPython side it called
AttributeError.name, a class attribute set to None, inherited.

Ownership now means the class dictionary holds the name. An inherited
member is reported only when what it resolves to differs from CPython's
own, so dict_items.__doc__, a slot CPython fills with None that
RustPython resolves to None without one, stays quiet. "(inherited)"
lines drop from 196 to 54, and ast.alias.end_lineno is among the real
gaps that appear.

Assisted-by: Claude Code:claude-fable-5-1
2026-09-20 18:39:44 +09:00
Jeong, YunWon 27647e1e4a Add _thread.get_native_id (#8754)
Return the kernel thread id (gettid / pthread_threadid_np /
GetCurrentThreadId). threading.get_native_id and Thread.native_id
follow once the function exists.

Assisted-by: Grok:4.6
2026-09-20 18:38:28 +09:00
Jeong, YunWon e0df2a10f0 Update malachite to 0.12 (#8755)
malachite-bigint 0.12.0 was published while the workspace pinned 0.11.0.
pymath requires malachite-bigint = "0", so a fresh resolve picks 0.12 for
it and leaves the workspace on 0.11, putting two incompatible BigInt types
in one graph. example_projects carry no lockfile and resolve fresh.

malachite-q and malachite-base move with it. No source change is needed.

Assisted-by: Grok:grok-4.6
2026-09-20 18:37:36 +09:00
YujinBae 587880b9e1 Read decimal digit values from the bundled character database (#8748)
`char_to_decimal` carried its own sorted table of 590 decimal digit
characters, added in #5643 because `common` had no way to reach the
Unicode numeric data at the time: it lived in `stdlib`, which sits above
`common` in the dependency graph. The table's own comment said as much —
"this should probably live in a crate like unic or unicode-properties".

#8211 extracted that data into `rustpython-unicode`, below `common`, and
made `common` depend on it, so the table can now be dropped in favour of
`Ucd::decimal` — the same source `unicodedata.decimal` consults.

This fixes a CPython incompatibility. The table was last updated for
Unicode 10; the bundled UCD is Unicode 17, which has 180 more decimal
digits across 18 scripts (Hanifi Rohingya, Wancho, Tangsa, Ol Onal,
segmented digits and others). Those were rejected by `int()` and
`float()` even though `unicodedata.decimal` knew their value:

    >>> int('\u{10D33}')        # HANIFI ROHINGYA DIGIT THREE
    ValueError                  # CPython: 3
    >>> unicodedata.decimal('\u{10D33}')
    3

All 590 characters the table covered keep their previous value, so
nothing that already worked changes, and the two lookups can no longer
drift apart on a future Unicode update.

The lookup costs about 1.5ns more per non-ASCII character, since it reads
a property trie and a value table instead of binary-searching one 2.4KB
array: `int()` over a 4000-digit non-ASCII string goes from 12.2 to
13.6 ns/char. ASCII input never reaches it — the sole caller,
`transform_decimal_and_space_to_ascii`, returns early for ASCII strings —
so ordinary numeric parsing is unaffected.

Assisted-by: Claude Code:claude-opus-5
2026-09-20 17:48:22 +09:00
hyoinandout 4c7cc0a30c lzma: treat empty input as a no-op, not end of stream (#8752)
decompress_chunks reports whether the codec signalled LZMA_STREAM_END,
and it short-circuits when the chunker has nothing left to feed. That
early return answered "the stream ended" for the case where no input was
supplied at all, so LZMADecompressor.decompress(b"") claimed a finish the
decoder had never signalled.

The caller latches that answer with `self.eof |= stream_end`, which only
ever flips eof on. A single empty call therefore finished the object for
good: needs_input went false and every later call was rejected by the
`if self.eof` guard with EOFError, before a single compressed byte had
been seen. CPython leaves eof false and needs_input true, and accepts
compressed data handed over by a later call.

  d = lzma.LZMADecompressor()
  d.decompress(b"")   # d.eof was True, now False
  d.decompress(blob)  # was EOFError, now b'data'

The zlib engine returns false from the same short-circuit; lzma had
drifted away from it. bz2 was fixed incidentally by #8638 when its engine
moved into crates/common, so only lzma needed a code change.

Verified on macOS arm64 against CPython 3.14.7: the script from the issue
now prints the documented "False True" and b'data' for both
decompressors. test_decompressor_chunks_empty in Lib/test/test_lzma.py
covers exactly this and no longer needs its expectedFailure marker. The
added engine test is named after the zlib one that already existed and is
mirrored into bz2, so all three engines stay pinned to the same
behaviour. test_lzma, test_bz2, test_zlib, test_gzip, test_tarfile,
cargo test --workspace, cargo fmt --check and cargo clippy
-p rustpython-common --all-features --all-targets -D warnings are clean.

Fixes #8637

Assisted-by: Claude Code:claude-opus-5
2026-09-20 17:22:27 +09:00
Jeong, YunWon f759c18a0e Take &Py<T> instead of bare payload references (#8753)
* Drop gc_traversal from CodSpeed benches

Remove benches/benchmarks/gc_traversal.py so CodSpeed no longer
includes that execution benchmark.

Assisted-by: Grok:4.6

* Take &Py<T> instead of bare payload references

Change `&PyCode`, `&PyInt`, `&PyTuple`, `&PySlice`, `&PyStr`,
`&PyFunction`, `&PyList` and `&PyDict` in function parameters, closure
types and local type annotations to `&Py<T>` where every caller already
holds a `Py<T>`.

Assisted-by: Claude Fable 5.1
Assisted-by: grok-4.6
2026-09-20 17:13:17 +09:00
hyoinandout c857f3acfd mmap: correct find/rfind for empty subsequences (#8749)
get_find_range clamped end up to start, so an inverted range such as
(2, 1) became the empty-but-valid range (2, 2). A real subsequence then
found nothing there, which looked right, but the empty subsequence
matched and both methods reported a hit where CPython reports -1.

rfind also returned the start of the range for an empty subsequence,
because its body was copied from find and the returned edge was never
adjusted. An empty subsequence matches at the edge the scan begins
from, so a reverse scan must report the end.

Dropping the clamp lets an inverted range stay inverted and be rejected
explicitly. find and rfind now share find_inner, which keeps the two
directions from drifting apart again, and it checks the mmap is open
before inspecting the subsequence, so find(b"") on a closed mmap raises
ValueError instead of returning a position.

  m = mmap.mmap(-1, 3); m[:] = b"abc"
  m.rfind(b"")        # was 0, now 3
  m.rfind(b"", 1, 2)  # was 1, now 2
  m.find(b"", 2, 1)   # was 2, now -1
  m.rfind(b"", 2, 1)  # was 2, now -1

Verified on macOS arm64 against CPython 3.14.7 with a 19-case table
covering both methods over empty and non-empty subsequences, clamped,
negative and inverted ranges: 8 mismatches before, none after. The
added snippet assertions fail on the unpatched build and pass on
CPython 3.14.7 as well. test_mmap, cargo fmt --check and
cargo clippy -p rustpython-stdlib -D warnings are clean.

Fixes #8722

Assisted-by: Claude Code:claude-opus-5
2026-09-20 16:01:10 +09:00
Jeong, YunWon 4cc7559aeb Drop gc_traversal from CodSpeed benches (#8750)
Remove benches/benchmarks/gc_traversal.py so CodSpeed no longer
includes that execution benchmark.

Assisted-by: Grok:4.6
2026-09-20 14:56:46 +09:00
Jiwoo Ahn 2006c63dfe ci: run wasm-wasi snippets and tests from declared lists (#8747)
- Declare two lists (for wasm-wasi snippets and List/test files) and loop over them instead of one wasmer run line per file.

- Add ten passing test scripts under wasm32-wasip1

Assisted-By: Claude Sonnet 5 <noreply@anthropic.com>

Signed-off-by: Jiwoo Ahn <ikwydls1314@gmail.com>
2026-09-20 14:23:44 +09:00
Jeong, YunWon 7bc3ef6c0a ExceptionGroup fields, OSError use-init, and live f_lineno (#8738)
* Add ExceptionGroup fields and OSError use-init

BaseExceptionGroup stores msg, excs, and excs_str; args keep
the original sequence. OSError defers parse when a subclass
overrides only __init__. characters_written can be deleted.
Exception args/traceback/cause/context reject invalid
setattr/delattr. UnicodeError.object is a deletable field.
except* remainder projection copies traceback/context/cause.
SyntaxError.__init__ clears omitted location attributes.

Assisted-by: Grok:grok-4.6

* Fix OSError payload init and UnicodeError construction

new_payload_exception now runs slot_new so BlockingIOError
parses characters_written. new_exception falls back to
invoke_exception for extra-payload types. Mixed tab/space
UnexpectedIndentation is TabError. AttributeError pickle
omits obj.

Assisted-by: Grok:grok-4.6

* address review: classify TabError from error line

Assisted-by: Grok:grok-4.6

* Add new_simple_exception; fill SyntaxError and f_lineno

new_exception constructs extra-payload types; BaseException-sized
types use new_simple_exception. Non-UTF-8 SyntaxError sets location
and text. Codegen errors load text via ProgramText. Keep Missing
parentheses capitalization. f-string adjacent atoms report a missing
comma. f_lineno may be None; lasti is not restored on unwind.

Assisted-by: Grok:grok-4.6

* address review: skip f-string continuation keywords

Assisted-by: Grok:grok-4.6

* Fix clippy map_unwrap_or in Non-UTF-8 offset

Assisted-by: Grok:grok-4.6

* Rename encode error ctor and exception setters

new_unicode_encode_error_real is new_unicode_encode_error.
set___traceback__/__cause__/__context__ are pygetset setters;
Rust uses set_traceback/set_cause/set_context.

Assisted-by: Grok:grok-4.6

* Use set_context in native pickle

Assisted-by: Grok:grok-4.6

* Collapse nested if in asyncio traceback restore

Assisted-by: Grok:grok-4.6

* Use current instruction for f_lineno addr2line

lasti is stored as the next instruction index. addr2line of
that byte offset is past RETURN_VALUE, so f_lineno was None
and stdlib_threading_current_frames hung on leftover workers.

Assisted-by: Grok:grok-4.6

* Look up format args, dir class, and frame builtins

Consume printf args before rejecting unknown conversions.
object.__dir__ uses getattr of __class__/__dict__.
_PyEval_GetBuiltin looks up iter/__import__ on the frame.

Assisted-by: Grok:grok-4.6

* Fix builtin lookups after rebase and unxfail passing tests

Assisted-by: Grok:grok-4.6

* Restore RERAISE lasti and SyntaxError locations

RERAISE with oparg restores lasti from the exception table
before unwind, so leftover f_lineno matches the original raise.
Handler lookup still uses the raising instruction.

Indentation errors outrank print/exec missing-parentheses.
BOM-with-non-utf8, bytes literals, and global+nonlocal now
report the same offsets as the parser/symtable.

object.__dir__ keeps string keys; type.__type_params__ skips
the getset wrapper stored on builtin types.

Assisted-by: Grok:grok-4.6

* Unxfail syntax/import tests and bind jump locals

IMPORT_NAME passes fromlist None instead of an empty tuple.
Jumping f_lineno binds None into unbound localsplus slots.
str lstrip/rstrip copy subclasses to exact str when unchanged.

Assisted-by: Grok:grok-4.6

* Fix import_from callers and rename frame lineno

sqlite3.iterdump now passes fromlist as a PyObject.
FrameObject::lineno is the i32 helper; f_lineno is the getset.

Assisted-by: Grok:grok-4.6

* Pass sqlite fromlist without Into conversion

from_list.into() could not infer Into<PyObjectRef> at the
import_from call. The typed tuple already converts.

Assisted-by: Grok:grok-4.6
2026-09-20 14:22:58 +09:00
Jeong, YunWon f1b8b09492 Don't hold socket locks across blocking I/O (#8746)
accept/recv/send kept the socket RwLock during the syscall. After
fork, the child copied that held lock, so _ResourceSharer._afterfork
hung in listener.close().

Unskip fork connection pickling, pool task ref release, and spawn
thread-pool terminate. Add extra_tests for fork+accept close and
fork after DupFd.

Assisted-by: Grok:4.6
2026-09-20 10:34:09 +09:00
Jeong, YunWon 7d6612aab4 host_env: export remaining WinSock rffi constants (#8745)
Assisted-by: Claude
2026-09-20 08:26:59 +09:00
Jeong, YunWon 7f610e593f Fix ctypes from_buffer writes and unskip passing MP tests (#8744)
* Fix ctypes from_buffer writes and unskip passing MP tests

Write char-array .value/.raw through borrowed buffers instead of
Cow::to_mut(), which copied shared memory into a private buffer.

Unskip connection pickling, sharedctypes, Condition notify, and
concurrent.futures interpreter-shutdown tests. Cover forkserver
Condition notify and shared ctypes char arrays in extra_tests.

Assisted-by: Grok:4.6

* Unskip linux RLock repr; keep fork pickling hang skip

test_repr_rlock passed on Linux spawn/fork/forkserver. Connection
pickling hangs under the fork start method, so skip it only there.

Build the apple-container image from rust:bookworm; rust:bullseye
apt indexes 404.

Assisted-by: Grok:4.6
2026-09-20 06:43:30 +09:00
Joshua Megnauth 391668b483 host_env: Simplify, dedupe remove_dir_at (#8723) 2026-09-20 00:33:53 +09:00
Jeong, YunWon 02c2a1dfc6 host_env: export remaining Windows socket constants (#8743)
Assisted-by: Claude
2026-09-20 00:33:01 +09:00
Jeong, YunWonandLee Dogeon d02d81e740 perf: VM and runtime hot paths from pyperformance (#8737)
* time: use CLOCK_UPTIME_RAW for monotonic/perf_counter on Apple

CLOCK_MONOTONIC keeps advancing during system sleep on macOS, unlike
CPython's mach_absolute_time()-backed perf_counter/monotonic. Benchmarks
that spanned a laptop sleep recorded thousands of seconds for a single
iteration (pyperformance float/fannkuch showed ~1000x slowdowns).
Use CLOCK_UPTIME_RAW (equivalent to mach_absolute_time) on Apple targets
and report it as such in time.get_clock_info().

Assisted-by: Claude Code:claude-fable-5-1

* vm: derive f_lineno lazily instead of tracking prev_line per instruction

The dispatch loop wrote prev_line (a locations lookup plus a Cell store)
on every instruction only so f_lineno could read it. f_lineno now derives
the line from lasti and code.locations, prev_line is only maintained on
the cold tracing path for 'line' event de-duplication, the two use_tracing
reads per instruction are merged into one, and the pre-dispatch lasti
reload is replaced by the value just stored.

When a trace function is installed on an already-running frame (bdb
stepping back into an untraced caller, frame.f_trace assignment, a local
trace returned from the 'call' event on a resumed generator) prev_line is
synced from lasti so no spurious 'line' event fires.

Assisted-by: Claude Code:claude-fable-5-1

* vm: coalesce per-call thread-locals into one FRAME_SLOT_CACHE

set_current_frame ran on every frame enter/exit and touched three separate
thread_local! statics (each a _tlv_get_addr call on macOS). Merge them into
a single thread-local struct so the hot path does one TLS access.

Assisted-by: Claude Code:claude-fable-5-1

* vm: fold stop/finalizing checks into EVAL_BREAKER

eval_breaker_tripped ran three checks per bytecode: the finalizing flag,
a thread-local stop_requested lookup, and the EVAL_BREAKER load. Add
STOP_BIT and FINALIZING_BIT so the per-instruction check is a single
relaxed atomic load; the slow path (check_signals) still re-derives the
exact per-thread answer. The bits are set alongside the per-thread flags
and cleared under the stop-the-world exclusion.

Assisted-by: Claude Code:claude-fable-5-1

* gc: set the TRACKED bit with a plain store for freshly allocated objects

gc_bits is zero for a fresh allocation (both the freelist reuse path and
PyInner::new zero it), so track_new_object can initialise the bit with a
relaxed store instead of a fetch_or. Re-tracking resurrected objects keeps
the read-modify-write variant.

Assisted-by: Claude Code:claude-fable-5-1

* vm: skip thread exception publish when pushing/popping a None exc slot

Generator/coroutine resume pushes and pops an exc_info slot on every
send. When that slot is None the value returned by topmost_exception
cannot change (it skips None entries), so the thread-local exception
publish in push_exception/pop_exception is unnecessary.

Assisted-by: Claude Code:claude-fable-5-1

* vm: allocation-free keyword-call fast path and super() MRO walk

Keyword calls to plain functions where every parameter is filled exactly
once are reordered in place into the fast-locals layout (no IndexMap, no
keyword name clones); any mismatch falls back to the existing slow path
so error messages are unchanged. super().attr now walks the type's MRO
by reference instead of cloning every class into two Vecs per lookup.

Assisted-by: Claude Code:claude-fable-5-1

* builtins: cheaper enumerate and zip iteration

enumerate kept its counter as a BigInt behind a write lock and did bignum
arithmetic on every item; use a machine integer that promotes to BigInt
only for huge/negative starts or on overflow. zip pre-sizes its per-item
Vec so the common two-iterable case allocates once.

Assisted-by: Claude Code:claude-fable-5-1

* _asyncio: cache module objects and use native set/dict operations

Task registration re-resolved _asyncio module attributes and re-imported
contextvars on every task; the eager path additionally went through generic
call_method for set add/discard. Cache the module objects per thread
(validated by identity), split the contextvars cache from the task
containers, and use PySet/PyDict methods directly.

Assisted-by: Claude Code:claude-fable-5-1

* perf: use mimalloc as global allocator for rustpython CLI

Adds mimalloc (0.1.52, default-features = false) as the #[global_allocator]
for the rustpython binary, gated behind a new `mimalloc` feature enabled
by default on non-wasm targets (dep declared under
target.'cfg(not(target_arch = "wasm32"))'.dependencies, so wasm builds
never pull it in regardless of default-features).

Profiling a `t = (a, b, c)` loop showed malloc/free at ~40% of samples on
macOS with the system allocator. Switching to mimalloc gives consistent
wins across small-object-heavy workloads, medians over 5-9 interleaved
A/B rounds (release build, this machine):

  tuple (5M `(a,b,c)`)         1.020s -> 0.863s  (1.18x)
  4-thread tuple (5M total)    1.643s -> 1.382s  (1.19x)
  class instances (2M)         0.874s -> 0.797s  (1.10x)
  dict-heavy (200k x 20)       2.196s -> 1.992s  (1.10x)
  string-heavy (join x 20)     0.662s -> 0.592s  (1.12x)
  nqueens (pyperformance)      0.327s -> 0.286s  (1.14x)
  chaos (pyperformance)        0.204s -> 0.191s  (1.06x)
  richards (pyperformance)     0.154s -> 0.151s  (1.02x)
  go (pyperformance)           0.411s -> 0.405s  (1.01x)
  listcomp / fib               ~neutral (<=1%)

Peak RSS (/usr/bin/time -l): instances workload roughly unchanged
(29.0MB -> 29.1MB); dict-heavy workload actually drops (155MB -> 106MB),
likely because mimalloc reclaims freed pages more aggressively than the
system allocator across repeated large-dict churn.

`cargo build` and `cargo build --release` are warning-free with the
default feature set, and `cargo build --release --no-default-features
--features stdlib,threading,importlib,stdio,host_env` (mimalloc
excluded) also builds cleanly. CI's wasm32-wasip1 and other
--no-default-features build matrices in .github/workflows already omit
`mimalloc` from their feature lists and target wasm via the
cfg(not(wasm32)) dependency gate, so no workflow changes needed.

`rustpython -m test -j4 test_gc test_weakref test_threading test_dict
test_list test_tuple test_str test_bytes test_memoryview test_ctypes
test_mmap test_array` passes identically (2541 tests, 241 skipped) on
both the baseline and mimalloc binaries.

Assisted-by: Claude Code:claude-fable-5-1

* vm: cap dict/set table shrink and compact holes on resize

asyncio's eager task path (and its per-task bookkeeping sets in general)
repeatedly adds and discards distinct task objects from a handful of
long-lived sets (_eager_tasks, _scheduled_tasks). Two dict_inner issues
turned that steady-state churn into the dominant cost of async_tree_eager:

1. resize() picked a target size of `used * 2` with no floor, so once a
   churny set settled around 1-2 live entries it shrank to a table that
   the very next insert would already overflow, forcing a resize on
   almost every single add. Clamping to the original minimum table size
   (8) restores the headroom dict/set start with.

2. `entries` only ever grows (holes from deletions are never reclaimed),
   so resize()'s rebuild pass scanned every entry ever inserted into the
   dict's lifetime, not just the live ones - a set with a stable working
   set size but heavy churn grew this scan, and the dict's memory, without
   bound. resize() now compacts holes out of `entries` first, matching
   CPython's compacting hash table and keeping the shape-stamp fast path
   (which already requires a hole-free layout) reachable more often.

Measured with a standalone async_tree micro-benchmark (6 levels x 6
branches, pyperformance's bm_async_tree "none"/"eager" shape) run inside
one process for 10 asyncio.run() iterations, comparing medians of
interleaved binary runs on an otherwise idle machine:

- eager: ~2.91s -> ~0.86s median (about 3.4x)
- none:  ~1.98s -> ~1.23s median (about 1.6x)

A single fresh-process run (no in-process accumulation) still improves
by roughly 15-20% for eager, since the resize-storm from point 1 hits
even a single run's worth of task churn.

test_asyncio (34 files, all passing), test_dict, test_set, test_weakref,
test_weakset, test_ordered_dict, test_gc, test_descr, test_class, and
`cargo test -p rustpython-vm -p rustpython-stdlib` all pass.

Assisted-by: Claude Code:claude-fable-5-1

* _functools: add native _lru_cache_wrapper

RustPython had no native _functools._lru_cache_wrapper, so
functools.lru_cache always fell back to the pure-Python implementation
in Lib/functools.py (RLock, linked-list bookkeeping, closures). That
fallback dominates typing.Protocol's __instancecheck__ path: it calls
inspect.getattr_static, whose _shadowed_dict is itself lru_cache'd, so
every isinstance() check against a runtime-checkable protocol paid for
several pure-Python cache-wrapper calls plus lock acquisitions.

Add a native pyclass mirroring CPython's C _lru_cache_wrapper: a
reentrant lock scoped only around the cache lookup/insert steps (not
held across the wrapped call, matching CPython's threading behavior),
LRU ordering piggybacked on the cache dict's own insertion order
(move-to-end via del+reinsert, oldest evicted from the front) so no
separate key-comparison structure is needed, and __copy__/__deepcopy__
returning self to match CPython since __reduce__ (used only for
pickling) requires __qualname__, which wrapped non-function callables
such as functools.partial don't have.

Measured with a standalone script reproducing pyperformance's
bm_typing_runtime_protocols isinstance() loop (300 loops, medians of
5 interleaved runs): 0.260s -> 0.182s, about 1.43x faster. In
isolation, a cache-hit through lru_cache went from ~0.31s to ~0.07s
for 200k calls, now faster than calling the underlying function
uncached (matching CPython's C accelerator).

Verified with test_typing, test_abc, test_inspect, test_functools,
test_weakref, test_isinstance, and test_descr (all pass, matching the
pre-existing baseline, including test_functools's already-present
TestLRUC suite which now actually exercises the native implementation).

Assisted-by: Claude Code:claude-fable-5-1

* sre_engine: ASCII fast path for \d \s \w unicode category checks

is_uni_digit/is_uni_space/is_uni_alnum went through icu_properties'
GeneralCategory table lookup for every character, even the common
ASCII case. Add a `ch < 0x80` fast path that resolves directly via
std's ascii predicates, falling back to the full table only for
non-ASCII code points (Latin-1 supplement chars like 'A-umlaut' still
route through the table since they are alphanumeric but not ASCII).

Measured on a tight `re.findall(r"\w+", ...)` / `re.sub` loop over
mostly-ASCII text (interleaved A/B, 4 rounds, medians):
  re.sub:    1.178s -> 1.134s  (~3.7% faster)
  re.findall: 1.110s -> 1.062s (~4.3% faster)

Assisted-by: Claude Code:claude-fable-5-1

* vm: skip VM attach for no-op generator/coroutine __del__

Generator, coroutine, and async-generator dealloc always went through
drop_slow_inner's call_slot_del, which unconditionally attaches to a VM
(with_vm -> begin_interpreter_section -> per-interpreter thread-slot
hashmap lookup) before running del(), even though del() itself is a
documented no-op once the object is already closed or running - the
common case for a generator/coroutine consumed to completion.

Add PyTypeSlots::del_needed, an optional VM-free fast predicate checked
before call_slot_del/with_vm; generator, coroutine, and async_generator
install a check mirroring their own del() no-op branches, letting
drop_slow_inner and try_call_finalizer skip the VM attach entirely for
finished objects.

Standalone microbenchmarks (median of 5 interleaved runs):
- create+drain a 3-yield generator, 2M times: 1.099s -> 0.997s (-9%)
- pyperformance bm_generators shape (yield-from tree traversal): -4%
- pyperformance bm_coroutines shape (recursive fibonacci coroutines): -13%

Assisted-by: Claude Code:claude-fable-5-1

* _asyncio: skip full __import__ dispatch on module-cache hot path

with_asyncio_cache/with_contextvars_cache called vm.import("_asyncio"/
"contextvars", 0) on every Task/Future registration just to validate
their module-identity cache, even on the (overwhelming) hit path. That
still pays the full __import__ builtin dispatch (attribute lookup on
builtins, FuncArgs construction, native slot_call, ImportArgs parsing,
import_module_level) instead of a cheap sys.modules lookup. Added
fast_import_cached(), which checks sys.modules directly and only falls
back to vm.import on a miss (module missing/reloaded).

Measured with a standalone asyncio_tree-style microbenchmark
(6 levels x 6 branches, several asyncio.run() iterations per process,
median of 5 interleaved A/B rounds):
  none:      1.045s -> 0.895s (~14% faster)
  eager:     0.716s -> 0.591s (~17% faster)
  eager_tg:  1.023s -> 0.849s (~17% faster)

test_asyncio (all files), test_contextvars (module absent from this
checkout, pre-existing), test_weakref, test_weakset all pass/unchanged.

Assisted-by: Claude Code:claude-fable-5-1

* vm: skip VM-attach section in with_vm when already on the current interpreter

Object teardown (drop_slow_inner -> call_slot_del, try_call_finalizer,
weakref callbacks) calls with_vm(), which unconditionally went through
set_current_vm -> begin_interpreter_section: an INTERP_THREAD_SLOTS
HashMap lookup plus an Arc clone, even in the overwhelmingly common
case where the dropping thread is already attached to the exact
interpreter that owns the object (a __del__ object or weakref target
going out of scope mid-bytecode).

with_vm now checks whether the object's owning interpreter is already
the one on top of VM_STACK. Only the top of VM_STACK is ever ATTACHED
on a thread (every push is preceded by an attach, every pop restores
the enclosing attach), so when it matches we call f(vm) directly and
skip begin_interpreter_section/set_current_vm entirely. The rare
not-attached/different-interpreter cases (nested subinterpreters,
thread outside any VM, shutdown) fall through to the original
attach/detach path unchanged.

Interleaved release-build measurements (5 rounds, medians), plain-Rust
micro-scripts, no pyperf:
- 2M create+drop of a __del__ object: ~0.55s -> ~0.46s (~16% faster)
- 2M create+drop with a weakref callback: ~1.14s -> ~1.06s (~7% faster)
- 2M io.StringIO() create+drop: ~0.734s -> ~0.697s (~5% faster)
- fib(30) and a 5M-iteration tuple-unpack loop: unchanged (noise-level)

`sample` profiles of the __del__ benchmark confirm
begin_interpreter_section/ensure_thread_slot frames disappear after
the change.

Verified: `cargo test -p rustpython-vm --release`, and
`-m test -j4 test_gc test_weakref test_finalization test_threading
test_thread test_concurrent_futures test_os test_signal test_generators
test_io test_atexit test_sys` (test_interpreters module absent in this
tree, pre-existing). Also a 4-thread stress script hammering __del__
object creation against a concurrent gc.collect() loop for 10s, and a
threading+queue handoff dropping a __del__ object after cross-thread
transfer, both pass.

Assisted-by: Claude Code:claude-fable-5-1

* vm: general sys.modules fast path for vm.import

VirtualMachine::import always resolved and called builtins.__import__
(FuncArgs construction, native slot_call, ImportArgs::from_args, then
import_module_level) even when the module was already cached in
sys.modules. ~63 Rust stdlib call sites hit this on hot paths
(copyreg, pickle's reduce_newobj, warnings, asyncio, etc).

Add VirtualMachine::try_import_cached: for a plain absolute import
(level 0, empty from-list), if builtins.__import__ is still the
original import function (compared by identity against vm.import_func)
and the module -- or, for a dotted name, its top-level package -- is
already present and fully initialized in sys.modules, return it
directly, skipping the __import__ dispatch and import_module_level
entirely. Falls through to the existing slow path whenever the module
is uncached, still initializing, or __import__ has been overridden by
user code, so test_import/test_importlib/test_builtin overrides still
work.

Exposed import::is_module_initializing (refactored out of
import_ensure_initialized) so the fast path can check
__spec__._initializing the same way the slow path does.

Removes _asyncio's local fast_import_cached workaround (added in
cb2064f0e) now that vm.import itself has the same fast path generally.

Measured (interleaved A/B, 5 rounds, pickle.dumps of a plain object,
which hits copyreg import via reduce_newobj): ~2% wall-clock
improvement per call (baseline ~4.75s / 100k dumps vs ~4.66s
candidate), consistent across all rounds. Verified: overridden
__import__ still invoked, a replaced sys.modules is read through the
same accessor, and a self-importing/initializing module is not handed
out early -- all match baseline behavior.

test suite (test_import test_importlib test_builtin test_pkg
test_pkgutil test_runpy test_zipimport test_site test_warnings
test_copy test_pickle test_asyncio.test_tasks test_threaded_import
test_sys): 13/14 files pass; test_threaded_import fails identically on
baseline (ModuleNotFoundError, pre-existing, unrelated to this change).

Assisted-by: Claude Code:claude-fable-5-1

* _asyncio: bypass generic context.run dispatch in task_eager_start

task_eager_start ran the first step via context.run(coro.send, None),
which builds a bound `send` method object and then re-enters the
generic Callable/FuncArgs dispatch just to invoke context.run's own
generic call. Since eager tasks in async_tree_eager complete almost
entirely synchronously (no event-loop scheduling needed), this
per-task dispatch overhead dominated. Enter/exit the native PyContext
directly and call coro.send via a single call_method instead,
falling back to the generic path for non-native Context subclasses.

async_tree_eager median: ~705ms -> ~697ms across 5 interleaved A/B
rounds (~1% eager-only win); async_tree (none) unaffected (noise-level
delta). test_asyncio (all files), test_weakref, test_weakset pass;
pre-existing test_contextvars module-not-found failure unchanged from
baseline.

Assisted-by: Claude Code:claude-fable-5-1

* vm: drop scopeguard::defer! from generator/coroutine resume hot path

resume_gen_frame restored owner/exc-slot/frame-chain state via a
scopeguard::defer! closure that ran on every exit (Ok, Err, or panic).
Since the closure's body is the function's only tail expression, a
plain captured result plus explicit cleanup (the same shape with_frame
already uses for the analogous call path) covers both normal exit
paths identically; only the recursion-depth decrement keeps a
scopeguard, matching with_frame's precedent that this codebase does
not otherwise guarantee generator/frame state consistency across a
Rust panic (panic=unwind is not used to implement any Python-level
control flow here).

Delegation-chain benchmark (chain.py, forwarding N values through a
yield-from chain) measures a small but consistent win: ~2-5% less
wall time per forwarded value at depths 1/4/16 across interleaved A/B
rounds. Single-generator create+finish cost is a wash.

Assisted-by: Claude Code:claude-fable-5-1

* vm: run generator bodies through the call trampoline

`Py<FrameObject>::resume` built its `ExecutingFrame` with
`tailcall_enabled: false`, because a `TailCall` result had nowhere to go:
the trampoline was reachable only from `run_frame_fast`, whose entry frame
lives on the data stack and can never yield. So every ordinary Python call
made from inside a generator or coroutine body re-entered `run_frame_fast`
recursively instead of being flattened.

Generalize the trampoline to drive a heap-resident entry frame whose
enter/exit bookkeeping belongs to its caller, and whose `Yield` is a valid
terminal result rather than a panic. `FrameKind` now says, per frame, what
the trampoline owes it: `Entry` (exit it, caller frees the storage),
`GenEntry` (`resume_gen_frame` linked it and will unlink it; a `Yield` is
the trampoline's result) or `Callee` (exit it and free its storage). The
three near-identical dispatch arms collapse into one `Step::Finished` /
`Step::Deliver` loop.

The suspended-frame stack moves onto the VM and is reused across
invocations: a generator body enters the trampoline once per resume, so a
`Vec::with_capacity(8)` there cost a malloc/free per yield (+27 ns/resume
when first measured). Invocations nest strictly LIFO, so each owns the
region above the length it finds on entry.

Neutral on its own — a generator body's first call was the only one not
already flattened, since the callee's own frame runs under the trampoline
either way. It is what lets SEND/FOR_ITER hand a generator frame to the
same loop. Measured (chain of `yield from`, 1-yield generator create+finish,
bm_generators, bm_coroutines, async_tree none/eager): within noise, except
generator create+finish 625 ns -> 603 ns.

Assisted-by: Claude Code:claude-fable-5-1

* vm: run a `yield from` chain in one eval loop

`SEND` on a suspended generator recursed: `Coro::send` -> `resume_gen_frame`
-> a fresh `ExecutingFrame::run` per level, and the value came back the same
way. Measured at ~55 ns per level of delegation, against CPython's ~5.8 ns.

Only about 5 ns of that is the resume bookkeeping itself (measured by
stubbing out the claim, the exception slot, the owner swap and the recursion
checks). The rest is what a delegating frame does per value: leave and
re-enter the eval loop, and dispatch `RESUME`, `JUMP_BACKWARD_NO_INTERRUPT`,
`SEND` and `YIELD_VALUE` — four instructions that, in the canonical
`yield from` / `await` shape, only hand a value along.

So the trampoline now runs the chain itself. `SendGen` parks its frame and
returns `ExecutionResult::GenResume`; the trampoline claims and links the
sub-generator (`coroutine::flat_resume_enter`, the first half of what
`Coro::send` does around a resume) and runs its frame in the same loop. On
the way down, every frame it finds already suspended at a `yield from` whose
delegate can be resumed is parked without being run at all
(`yield_from_delegate`); on the way back up, a yielded value is re-yielded
for each such frame by parking its `lasti` past the `YIELD_VALUE`
(`park_after_yield_from`) instead of running it. A whole chain therefore
costs one claim/link/unlink per level and no instruction dispatch at all,
with `Py<FrameObject>::resume` extending the same treatment to the outermost
level, which is where `next()` and asyncio's task step enter a chain.

Each level is still claimed, linked and unlinked exactly as a recursive
`Coro::send` would, so `gi_running`, `f_back`, `gi_frame`, `gi_yieldfrom`,
`sys._getframe`, tracebacks, `throw`, `close`, PEP 479 and the
`RecursionError` depth are unchanged; `resume_gen_frame` and the flat path
share `gen_frame_link`/`gen_frame_unlink` and the invariants are documented
on `FlatResume`. Everything else keeps the recursive path: tracing or
monitoring on (both would see the skipped instructions), `throw`/`close`,
async generators, subclasses, non-generator iterators, `FOR_ITER`, a `SEND`
that is not a `yield from`, and a delegate that has not started or is not
itself delegating — the last two because one lone level costs more to hand
to the trampoline than to send into from the eval loop the caller is in.

Measured (median of 5, ns/value or seconds):

    chain of `yield from`, depth 16   911   -> 479   -47%
    chain of `yield from`, depth 4    212   -> 158   -26%
    bm_generators                     0.272 -> 0.187 -31%
    richards                          0.772 -> 0.771    ~0
    bm_coroutines                     0.0129 -> 0.0130 +0.8%
    async_tree none                   ~neutral
    chain depth 1 (no delegation)     81.1  -> 83.6  +3.1%
    fib(24), calls through trampoline 0.0180 -> 0.0183 +1.7%

Per level of delegation: 55.3 ns -> 26.4 ns (CPython 3.14: 5.8 ns).

Assisted-by: Claude Code:claude-fable-5-1

* vm: reset the oparg prefix when a signal unwinds a frame

An `EXTENDED_ARG` leaves its prefix in `arg_state` for the instruction that
follows it. The signal path in the eval loop unwinds to a handler and
`continue`s straight back to the top, skipping the loop's own
`arg_state.reset()`, so the handler's first instruction was decoded with the
interrupted instruction's prefix still applied. Every other path that jumps
somewhere new — the `set_f_lineno` restart just above — resets first.

Reachable whenever a signal arrives on the instruction right after an
`EXTENDED_ARG` in a frame that has a handler: a `KeyboardInterrupt` into a
`yield from` chain panicked with `InvalidBytecode` in roughly half of the
runs of a 16-deep chain, and now does not in ten out of ten.

Assisted-by: Claude Code:claude-fable-5-1

* bytecode: fetch a code unit with one 16-bit acquire load

The dispatch loop read the opcode with an Acquire `AtomicU8` load and the
arg byte with a separate Relaxed one. The acquire load sits between the
two, so LLVM had to re-load `self.code` and `code.instructions` for the
second access: four extra instructions and two extra dependent loads on
the instruction-fetch path of every bytecode instruction.

`CodeUnits::read_unit` reads both bytes as a single aligned Acquire
`AtomicU16`, which pairs with `replace_op`'s Release store exactly as
`read_op` did. `CodeUnit` gains `align(2)` so the 16-bit access is
guaranteed aligned rather than relying on the allocator.

5.91 -> 5.76 ns/bytecode-instruction on a straight-line
LOAD_FAST/STORE_FAST loop (-2.5%); range loop -2%.

Assisted-by: Claude Code:claude-fable-5-1

* vm: compute the cache-entry count after dispatch, not before

`op.cache_entries()` is a byte-table lookup used only to skip inline
cache units after an instruction falls through. Computing it before the
handler kept it live across the whole (very large) inlined match, so
every bytecode instruction paid an address materialization, the table
load, a stack spill and a reload of the count.

Moving it next to its only use lets it be computed on the fall-through
path with the value in a register.

Measured together with the following commit (the eval-breaker outline):
5.76 -> 5.55 ns/bytecode-instruction on a straight-line
LOAD_FAST/STORE_FAST loop, range loop -1.5%, fib(27) -2.5%.

Assisted-by: Claude Code:claude-fable-5-1

* vm: move the eval-breaker body out of the dispatch loop

The eval-breaker check itself stays inline on the per-instruction path
(moving it off regresses badly), but everything it guards -- the
finalizing/main-thread check, stop-the-world suspend, the QSBR
checkpoint, signal delivery and the scheduled GC -- was inlined into the
loop body too. That code is never executed on the hot path yet its
address materializations and live values competed for registers with
every opcode handler, so the loop head spilled more than it needed to.

`eval_breaker_work` is `#[cold] #[inline(never)]`, leaving a single
`ldrb`/`cbz` pair inline for the common "nothing pending" case.

Measured with the preceding commit: 5.76 -> 5.55 ns/bytecode-instruction
on a straight-line LOAD_FAST/STORE_FAST loop.

Assisted-by: Claude Code:claude-fable-5-1

* vm: always inline the eval stack push/pop primitives

`pop_value`, `pop_value_opt`, `top_value` and friends are a handful of
instructions each, but `ExecutingFrame::run` is ~50 KB of inlined opcode
handlers, so LLVM's inline budget refused them and emitted real calls:
STORE_FAST and POP_TOP each began with `bl ...pop_value`, which also
forced spills around the call. `#[inline(always)]` puts the four or five
instructions they actually are back into the handlers.

5.55 -> 5.29 ns/bytecode-instruction on a straight-line
LOAD_FAST/STORE_FAST loop (-4.8%); nbody -3.5%, fib(27) -3.5%,
`s += i` loop -3.5%, `for _ in range(n)` -4%.

Assisted-by: Claude Code:claude-fable-5-1

* vm: carry the instruction fetch state in loop locals

Instruction fetch went through memory three times per bytecode
instruction: `self.lasti` (a pointer field) was re-loaded, the program
counter was stored to it and read back at the top of the next iteration,
and `self.code` -> `code.instructions` was re-loaded to address the code
unit. LLVM cannot keep any of them in registers because the handlers
write through `&mut self`, so the fetch chain started with a
store-to-load round trip followed by two dependent pointer loads.

`lasti_cell` and `instructions` are now copied into locals once (both are
plain shared references with the frame's lifetime), and the program
counter is carried in `idx`: after a handler that did not jump the next
index is already known from `lasti_before` plus the cache count. The
frame's `lasti` is still stored before every instruction, so tracebacks,
`f_lineno`, signals and `sys._getframe` see exactly what they did; only
the read-back is gone. The paths that unwind (signal, exception handler,
`set_f_lineno`) re-read it, since they jump to a new position.

Also collapses the eval-breaker `if`, which clippy flagged after the
previous commit moved its body out of line.

range loop -3.3%, richards -3.1%, nbody -2.9%, `s += i` loop -2.2%,
go -1.7%, raytrace -1.2%; mean -1.1% over the 13-benchmark set. The
straight-line LOAD_FAST/STORE_FAST micro is unchanged at 5.28
ns/bytecode-instruction (it has no cache entries and never jumps, so it
was already the best case for the old code).

Assisted-by: Claude Code:claude-fable-5-1

* bytecode: hoist the instruction array base out of the dispatch loop

Addressing a code unit still went `self.code` -> `code.instructions` ->
the `Box<[CodeUnit]>` data pointer on every instruction, two dependent
loads before the acquire load that fetches the unit itself, because the
handlers write through `&mut self` and LLVM has to assume the fields
could change.

The instruction array is allocated once when the code object is built
and never reallocated -- specialization rewrites units in place -- so
`CodeUnits::units_ptr` may be read once before the loop and reused.
`read_unit_from` is the same 16-bit acquire load taken from that base;
`read_unit` now delegates to it, and the index is unchecked exactly as
it was before.

nqueens -1.9%, raytrace -1.6%, range loop -1.3%, deltablue -1.1%,
nbody -0.8%, dispatch micro -0.7%; mean -0.7% over the 13-benchmark set.

Assisted-by: Claude Code:claude-fable-5-1

* common: an immortal bit in the refcount word

Atomic reference counting is about a third of what a bytecode costs now
that the dispatch loop is trimmed: built `--no-default-features`, where
`PyAtomic` is a `Cell`, the straight-line dispatch micro runs at
3.5 ns/instruction against 5.4. Every `TO_BOOL`/`POP_JUMP_IF_*` pair and
every `None` or small-int push pays a relaxed `ldadd` and a `Release`
`ldaddl` on an object that can never die.

PEP 683's answer is to say so in the word. A fourth flag bit, `IMMORTAL`,
takes a bit from the strong count (leaving 60 on a 64-bit target, 28 on a
32-bit one, both far past what a program reaches); `make_immortal` sets it
and parks the count at CPython's `_Py_IMMORTAL_REFCNT`, and `inc`,
`inc_by`, `dec` and `safe_inc` read the bit and return without touching
the counter. The parked count is what keeps the rest of the tree honest
without a special case: it is far too large for a `strong_count() == 1`
in-place-mutation fast path to fire on, and `start_gc_refs` already reads
a count that large as `GC_REACHABLE`, so an immortal object is a permanent
root that keeps its referents alive.

Two details pay for the branch the mortal path now runs, which cost 4% on
object-heavy benchmarks before they went in:

* `leak` sets `IMMORTAL` alongside `LEAKED`. An interned object could
  already never reach zero, so `dec` no longer needs the test it made on
  the result of the decrement: the immortal test at the top decides both.
* `inc`'s three exceptional cases — a destructed word, a count at the
  ceiling, a count at zero — fold into one comparison against the masked
  word, with the handling moved to a cold helper.

What is left is one instruction on `dec` and roughly nothing on `inc`, and
the mortal path measures at parity.

Assisted-by: Claude Code:claude-fable-5-1

* vm: make the singletons, small ints, interned strings and static types immortal

Everything the `Context` builds once and keeps — `None`, `True`, `False`,
`Ellipsis`, `NotImplemented`, the empty tuple, frozenset, bytes and str,
the -5..256 int cache and the interned one-character strings — is now
marked immortal, as is every static type object, which its `static_cell`
holds for the life of the process. So is every entry of the string pool:
`mark_intern` already stopped those refcounts from reaching zero, so
immortality frees no memory that would otherwise have been freed; it only
takes the atomic read-modify-write off every incref and decref of an
attribute name, a dict key or a docstring.

Straight-line dispatch micro (200 LOAD_FAST/STORE_FAST pairs over cached
ints, median of 5 interleaved runs): 5.39 -> 4.01 ns/instruction, -26%.
A four-thread `if flag:` loop, where the contention on the shared bool was
real: 2.36 s -> 2.14 s, -10%.

pyperformance bench functions run standalone, medians of 5 interleaved
rounds against a matched build: fannkuch -7.8%, nqueens -3.8%, chaos
-3.0%, raytrace +1.0%, go +1.2%, richards +4.2%, nine of them together
-2.9%. Per-benchmark deltas under about 4% sit inside this tree's
build-to-build ThinLTO layout noise, which reaches that size between two
builds of identical source.

Observable: `sys.getrefcount` of an immortal object reports 4294967295,
CPython's `_Py_IMMORTAL_REFCNT`, and stops moving — what
`test_sys.test_refcount` expects of `None`. `is_interned`, and the dict
pointer-equality key fast path behind it, keep answering from the separate
`LEAKED` bit.

Assisted-by: Claude Code:claude-fable-5-1

* codecs: fast-path utf-8 decode, skipping the codec registry round trip

bytes.decode('utf-8') / str(bytes, 'utf-8', ...) always went through the
generic codec registry: a per-call attribute lookup for
_is_text_encoding, then a full call into the pure-Python
encodings.utf_8.decode wrapper, which called back into the native
utf_8_decode and unpacked a 2-tuple result.

CPython's PyUnicode_Decode special-cases a handful of built-in encoding
names (utf-8 among them) and decodes them directly, bypassing the codec
registry entirely -- a codecs.register() override does not affect
str(b"...", "utf-8") there either. This adds the same fast path here:
recognized utf-8 aliases go straight to the native decoder.

Measured with a pure-Python `str(bytes, 'utf-8', 'surrogatepass')` loop:
~723ns -> ~401ns per call (1.8x). On the pyperformance unpickle
benchmark (which decodes short strings this way for every
SHORT_BINUNICODE opcode): ~14.4ms -> ~13.2ms per loop, an ~8.3% win.

Assisted-by: Claude Code:claude-fable-5-1

* codecs: fast-path utf-8/ascii/latin-1 encode and ascii/latin-1 decode

Extend the utf-8 decode fast path from 3fe684629 to the symmetric encode
direction (str.encode()/bytes(s, enc)), and add the same registry-skipping
fast path for ascii and latin-1 encode/decode, all of which are simple
native codecs.rs functions already. For utf-8 encode with no surrogates in
the string (the common case), encoding is just a copy of the string's
existing UTF-8 bytes, so that's the fastest path; strings containing
surrogates and non-strict error handlers still go through the native
encoder + ErrorsHandler, matching custom codecs.register_error handlers.

Measured (median of interleaved runs vs baseline, 2M iterations):
  str.encode("utf-8"):   351ns -> 195ns  (-44%)
  str.encode():          449ns -> 291ns  (-35%)
  bytes(s, "utf-8"):     542ns -> 382ns  (-30%)
  str.encode("ascii"):   436ns -> 302ns  (-31%)
  str.encode("latin-1"): 487ns -> 333ns  (-32%)
  bytes.decode("ascii"): 519ns -> 359ns  (-31%)
  bytes.decode("latin-1"):590ns -> 417ns (-29%)
  bytes.decode("utf-8")/str(b,"utf-8"): unchanged (already fast-pathed)

Assisted-by: Claude Code:claude-fable-5-1

* vm: make the runtime safe for borrowed stack entries

`PyStackRef` has carried a borrow tag since the stack was unified with the
fastlocals, but only `LOAD_SMALL_INT` -- which borrows immortal `Context`
objects -- ever set it, so nothing in the runtime had to be right about
borrowed entries. Turning `LOAD_FAST_BORROW` into a real borrow makes three
places load-bearing, and this fixes them ahead of the switch.

`Traverse for PyStackRef` handed every entry to the tracer, borrowed ones
included. The cycle collector subtracts one from an object's `gc_refs` per
edge it is shown, so a borrowed entry -- which owns no strong count -- would
have pushed a live object's count to zero and freed it out from under the
frame. Borrowed entries are now skipped; nothing becomes unreachable, because
the fastlocals slot the entry borrows from is on the same traversal.

`park_after_yield_from` stands in for a `YIELD_VALUE` that never runs, so the
`promote_stack()` in that handler never ran either; it now promotes there too,
and the debug assertion after it stops being vacuous.

`STORE_FAST`, `DELETE_FAST` and the fused stores now call
`LocalsPlus::debug_audit_local_release`, which in debug builds panics if the
slot is about to drop the last count of an object a borrowed entry still
points at -- the one shape codegen's `optimize_load_fast` exists to prevent,
and the one that would be a use-after-free if the analysis or a modelled stack
effect were wrong.

`BORROW_LOCAL_LOADS` (off) is the switch for the borrow itself, and
`LOAD_FAST_BORROW`/`LOAD_FAST_BORROW_LOAD_FAST_BORROW` now go through
`push_local`, which is a plain clone while it is off. The invariant the switch
depends on is written out where `PyStackRef` is defined.

No measurable change: with the switch off the only behavioral difference is
the traversal fix, which no current bytecode can reach.

Assisted-by: Claude Code:claude-fable-5-1

* vm: read consumed stack entries in place instead of owning them

`pop_value()` turns whatever is on the stack into an owned `PyObjectRef`, so
an instruction that only reads its operand still pays a reference count round
trip -- and, once `LOAD_FAST_BORROW` starts pushing borrows, would pay an
atomic increment to promote a borrow it is about to throw away. This moves
every consumer that never needs ownership onto `pop_stackref()`, which hands
back the tagged entry and costs nothing for a borrow.

Discarding pops (62 of them, across the `LOAD_ATTR`, `TO_BOOL`, `BINARY_OP`,
`COMPARE_OP`, `CONTAINS_OP` and `CALL` specializations, which read their
operands through `top_value()`/`nth_value()` and then drop them) become
`pop_stackref()`. So do the read-only operands of `POP_TOP`, `POP_JUMP_IF_*`,
`TO_BOOL`, `BINARY_OP`, `COMPARE_OP`, `CONTAINS_OP`, `IS_OP`, `STORE_ATTR`,
`DELETE_ATTR`, `STORE_SUBSCR`, `DELETE_SUBSCR` and `UNPACK_SEQUENCE`.

Two protocol entry points had to move from an owned receiver to `&PyObject` to
make that reachable: `try_to_bool`, which never used the ownership it took,
and `rich_compare`, which forwards to the `&self` `_cmp` anyway. Both keep
working unchanged for `PyObjectRef` callers through deref.

`LOAD_ATTR`'s method specializations popped the receiver and pushed it
straight back below the bound function; they now move the entry across with
its tag intact, which is how CPython keeps a method call's receiver borrowed
from `LOAD_ATTR` all the way through `CALL`. The plain attribute read reads
through the receiver rather than owning it.

Neutral while `BORROW_LOCAL_LOADS` is off -- for an owned entry
`pop_stackref()` and `pop_value()` compile to the same thing.

Assisted-by: Claude Code:claude-fable-5-1

* vm: turn LOAD_FAST_BORROW into an actual borrow

`LOAD_FAST_BORROW` accounts for 21.5% of executed instructions on
nbody+richards+nqueens, and until now it did exactly what `LOAD_FAST` does:
an atomic increment on the way onto the stack and, from the instruction that
consumed it, an atomic release decrement on the way off. Neither is needed.
The fastlocals slot holds a count for as long as the entry is on the stack --
codegen's `optimize_load_fast` only rewrites a `LOAD_FAST` when it can prove
the entry is consumed before anything can release that slot -- so the entry
can be a borrow that owns nothing, which is what CPython 3.14 does with a
tagged `_PyStackRef`.

Flipping `BORROW_LOCAL_LOADS` on is the whole change; the two preceding
commits are what make it safe (cycle-collector traversal, yield-point
promotion, a debug audit of the invariant) and what make it pay (consumers
that read through the entry rather than promoting it back to owned).

Medians of 7 interleaved rounds, this machine, against the pre-series binary:

  straight-line while loop   6.32 -> 6.01 ns/instruction  (-5.0%)
  x = a + b loop             -6.3%      if flag: loop     -3.8%
  attribute-read loop        -5.2%      method-call loop  -3.3%
  subscript loop             -6.7%      fib(27)           -0.8%

  nbody   -2.6%   fannkuch -1.7%   nqueens  +1.3%   richards -3.0%
  deltablue -2.3% go       -3.0%   raytrace -1.7%   float    -3.2%
  chaos   -2.6%   spectral_norm -2.5%      mean     -2.1%

About half of that is the consumer rewrite alone (mean -1.0% with the switch
still off) and the rest is the borrow. nqueens is the one benchmark that goes
the other way, by less than the roughly 4% of build-to-build layout noise this
tree has, and it moves with the consumer rewrite rather than the switch.

Full suite green (418 files, 42,110 tests). A build with debug assertions on
runs the suite with no audit failure, and trips the audit exactly when
`LOAD_FAST` is forced to borrow in a shape codegen refuses to convert
(`f(x, (x := None))`). Adversarial scripts -- swap loops and reassignment
under `__del__` tracking, argument evaluation that deletes its sibling,
`a[a.pop()]`, closures over a rebound cell, generators dropped while
suspended, tracebacks whose `f_locals` are read after unwinding, `settrace`
writing `f_locals` mid-expression, a method receiver whose local is cleared
while the call is being built, `__add__`/`__lt__`/`__bool__` that clear the
local their operand came from, threads sharing objects through locals, and
`gc.collect()` from a finalizer -- all agree with CPython 3.13 under
`gc.set_threshold(1, 1, 1)`, in both builds.

Assisted-by: Claude Code:claude-fable-5-1

* vm: exact-dict fast path for DICT_MERGE and CALL_FUNCTION_EX kwargs

`g(**d)` on an exact dict compiled to BUILD_MAP+DICT_MERGE+CALL_FUNCTION_EX
and paid for two Python-level `keys()`/`__getitem__` round trips per key at
both the DICT_MERGE handler and collect_ex_args' iterate_mapping_keys, even
though the source is a plain dict. Add an exact-dict (downcast + type
check, so subclasses still go through the mapping protocol) fast path to
both sites that iterates entries natively via PyDict::items_vec, matching
CPython's PyDict_Check fast paths in PyDict_Merge / CALL_FUNCTION_EX.

Measured (1M calls, release build): g(**d) 1320ns -> 665ns, f(**d)
1470ns -> 900ns, c.m(**d) 1690ns -> 1135ns, f(x=1,**d) 1600ns -> 1035ns,
f(**d1,**d2) 1700ns -> 1013ns. bm_django_template ~7% faster,
bm_argparse (subparsers) ~7% faster.

Assisted-by: Claude Code:claude-fable-5-1

* vm: skip the recursion guard hashing exact ints inside a tuple

tuple.__hash__ hashed every element through PyObject::hash, which wraps
each call in with_recursion's native-stack-depth check. That guard exists
for elements whose hash can recurse into arbitrary Python code, but
int.__hash__ is a leaf computation - it can neither recurse nor call back
into Python - so the check is pure overhead for the overwhelmingly common
case of tuples of plain ints (e.g. namedtuple-shaped dict keys).

pyperformance's mdp benchmark builds huge tables keyed by tuples of deeply
nested namedtuples whose leaves are ints; profiling with `sample` showed
PyObject::hash/with_recursion/tuple's slot_hash dominating the CPU time.
Hashing exact-int elements directly via hash::hash_bigint cuts mdp's
wall time from ~6.79s to ~4.81s (median of 5 interleaved runs), about 29%
faster, with no change to hash values or recursion-guard behavior for any
other element type.

Assisted-by: Claude Code:claude-fable-5-1

* vm: wire slot descriptors from __slots__ into C-level type slots

Classes that put a dunder name (e.g. "__setitem__") into __slots__ get
a per-instance member descriptor for it, which is a legitimate way to
override a special method per-instance (chameleon's tal.RepeatDict does
exactly this). PyType::new_verbose ran init_slots() to compute
mp_ass_subscript/mp_subscript/etc. before these member descriptors were
added to the type's attribute namespace, so the slot lookup never saw
them and __setitem__/__getitem__ silently fell back to "does not
support item assignment".

Fix by calling update_slot for each dunder-shaped __slots__ member
right after it is installed on the type, mirroring what
type.__setattr__ already does for regular attribute updates.

Assisted-by: Claude Code:claude-fable-5-1

* frame: stop allocating cold data to close a generator

`clear_locals_and_stack`, which runs whenever a generator or coroutine
comes to an end, reached for the frame's lazily-allocated `FrameColdData`
through `cold()`. That allocates it on first access, so every finishing
generator paid a `Box<FrameColdData>` malloc and free just to find
`f_extra_locals`, `f_locals_cache` and `f_overwritten_fast_locals` all
empty -- cold data is only ever populated by tracing and frame
introspection. Ask for it with `cold_opt()` instead and skip the three
reads when it was never allocated.

Medians of interleaved A/B runs, ns per generator create+finish over a
plain call: `for _ in g(): pass` 265 -> 231 (-13%), a coroutine that
completes synchronously 642 -> 617 (-4%), `sum(x for x in range(3))`
1033 -> 997 (-3.5%).

Assisted-by: Claude Code:claude-fable-5-1

* function: bind exact args straight into a generator's frame

Calling a generator, coroutine or async generator function took the
general argument-binding path even when the call site was the simplest
possible one. `invoke_exact_args_slots` and the vectorcall fast path both
recognised the shape -- every parameter positional, filled exactly once
-- and then handed generator-like code back to `invoke()`, which built a
`FuncArgs` (a `Vec` plus an `IndexMap`) only for
`fill_locals_from_args_inner` to walk varargs packing, keyword matching
and defaults that this shape cannot reach.

Add `make_generator_exact_args`, the counterpart of
`prepare_exact_args_frame` for the one call shape it refuses: it builds
the heap frame the generator will own, moves the arguments straight into
its fastlocals and returns the generator. Both fast paths now use it. The
vectorcall one matters on its own for generator expressions, whose fresh
`MAKE_FUNCTION` on every evaluation keeps them out of the call-site
specialization that would otherwise catch them.

Medians of interleaved A/B runs, ns per create+finish over a plain call:
`for _ in g(): pass` 231 -> 218 (-6%), a synchronously-completing
coroutine 616 -> 598 (-3%), `sum(x for x in range(3))` 1007 -> 967 (-4%).

Assisted-by: Claude Code:claude-fable-5-1

* frame: drain a dead frame in place instead of moving it out

Three allocations and a large move on the path a finishing generator
takes to release its frame.

`Traverse::clear` opened with `self.iframe.get_mut().take()`, moving the
whole `InterpreterFrame` -- a couple of hundred bytes -- out of its slot
and onto the stack, only to drop it there. Drain it through `as_mut()`
and empty the slot afterwards.

`LocalsPlus::clear_into` collected the evaluation stack into a `Vec` that
existed only to be extended into the caller's; push into that one
directly. And `clear_stack_and_cells` built (and dropped) a `Vec` for a
stack it had not looked at -- a frame that reached its `return`, which is
every generator that simply finished, left nothing there. Look first.

Medians of 5 interleaved rounds, ns per create+finish: `for _ in g():
pass` 307 -> 297 (-3.4%), a synchronously-completing coroutine 600 -> 585
(-2.5%), `list(g())` 565 -> 558; a plain call is unchanged.

Assisted-by: Claude Code:claude-fable-5-1

* vm: don't raise a TypeError to ask an iterator for its length

`length_hint_opt` opened with `iter.length()`, whose whole job on a type
with no length slot is to build the `TypeError` that says so -- which
this caller then catches, recognises and discards. Every iterator and
every generator takes that path, and `list()` calls it on whatever it is
handed, so a `list(gen)` paid for an exception object per call.
`length_opt` answers the same question with `None`. CPython's
`PyObject_LengthHint` gates the call on the slots for the same reason.

Median of 5 interleaved rounds: `list(g())` x200k for a 1-yield
generator 556 -> 407 ns (-27%). pyperformance generators, coroutines,
comprehensions and async_tree are unchanged, as are nqueens, richards
and chaos.

Assisted-by: Claude Code:claude-fable-5-1

* gc: track a generator and its frame in one pass

Making a generator tracks two objects that are born together and die
together -- the generator and the frame it owns -- and each one took the
gen0 list lock and a thread-local read of the running interpreter for
itself. Give the pair one entry point: `PyGenerator`, `PyCoroutine` and
`PyAsyncGen` opt out of tracking at allocation, the way frames already
do, and `make_generator_or_coro` links both into gen0 under a single
lock, with one owner read and one collection check.

Medians of 5 interleaved rounds: pyperformance coroutines -2.5%,
generators -0.9%; `for _ in g(): pass` over a plain call 205 -> 200 ns.

Assisted-by: Claude Code:claude-fable-5-1

* dict_inner: fast-path exact-int equality in key_eq

Mirrors CPython's lookdict: two exact `int` keys now compare by BigInt
value directly instead of going through the generic rich-compare
dispatch (identical_or_equal -> bool_eq -> rich_compare_bool -> __eq__
slot lookup). Falls back to bool_eq whenever either side isn't exactly
`int` (subclasses may override __eq__), so behavior is unchanged there.

Measured (min-of-6 rounds, 2M-iteration micros, this tree's build has
~4% layout noise so min is used as the noise floor):
- dict_int_lookup (`d[i]`, int keys): 70.9ns -> 62.0ns (-12.5%)
- dict_str_lookup / dict_tuple_lookup / set_str_contains: unchanged
  (within noise), confirming no regression on non-int keys.

pyperformance sanity checks (single round each, base vs candidate):
bm_mdp median ~5027ms/loop vs ~5003ms/loop (no regression, hashing
isn't the dominant cost there); bm_nqueens, bm_go, bm_deltablue,
bm_hexiom, bm_chaos all within ~1% (noise).

Hash/equality values cross-checked bit-identical against CPython 3.14
for 0, 1, -1, True, False, 2**61-1, 2**61, -(2**63), 2**100, -(2**100),
and int/float/bool/Decimal/Fraction(1) hash-equality invariants.

Also tried an exact-type fast dispatch in PyObject::hash (skipping the
slots.hash vtable call + with_recursion for exact int/str) - it only
moved hash_small_int/hash_large_int by ~2%, under the 3% bar, so it was
not committed.

Tests: `rustpython -m test -j4 test_hash test_int test_long test_tuple
test_dict test_set test_dictviews test_ordered_dict test_collections
test_fractions test_numeric_tower test_float test_bool test_str
test_userdict test_weakref` all pass (1796 run, 72 skipped). `cargo
test -p rustpython-vm --release -p rustpython-common` passes. clippy
clean on the touched lines.

Assisted-by: Claude Code:claude-fable-5-1

* vm: let the modulus type handle a three-argument pow

CPython's ternary dispatch offers the operation to the third operand's type
whenever its slot differs from the two already tried, including the case where
neither operand had one. The port required both of those slots to exist, so
`pow(10, 2, Decimal(7))` never reached `Decimal` and raised TypeError.

Assisted-by: Claude Code:claude-fable-5-1

* vm: add a feature-gated opcode-pair histogram

Counts `(prev_op, op)` in the dispatch loop and dumps the nonzero pairs at
exit, so superinstruction and specialization candidates can be ranked from
what pyperformance-shaped code actually dispatches rather than guessed at.

Entirely behind the non-default `opcode-histogram` feature: the module is
`#[cfg]`-ed out and the loop's two-line hook with it, so a default build is
byte-identical to one without the patch.

Assisted-by: Claude Code:claude-fable-5-1

* vm: let boolean producers run the branch that follows them

`TO_BOOL*`, `COMPARE_OP*`, `CONTAINS_OP*` and `IS_OP` materialised a bool
only for the `POP_JUMP_IF_*` one dispatch later to pop and test it, and the
compiler's `NOT_TAKEN` marker cost a third dispatch on the fall-through edge.
Generalise the `COMPARE_OP_INT`-only jump fusion so every boolean producer
resolves the jump itself, and step over `NOT_TAKEN` from there and from the
plain `POP_JUMP_IF_*` handlers. Both back off to ordinary dispatch when the
successor is an instrumented opcode or while tracing, so `sys.monitoring`
branch events and `sys.settrace` opcode events are unaffected.

Dispatches over 13 standalone pyperformance benchmarks: -5.0% total
(richards -11.7%, unpickle_pure_python -8.9%, sympy -8.4%, hexiom -8.1%,
django_template -7.1%, go -6.1%; nbody unchanged). Times, best of 7
interleaved rounds: deltablue -4.0%, hexiom -3.5%, go -3.4%,
unpickle_pure_python -3.3%, richards -3.2%, raytrace -3.0%, nqueens -1.9%,
geomean -1.0%; a branch-heavy microbenchmark -4.7% against a straight-line
control at 0%.

Assisted-by: Claude Code:claude-fable-5-1

* Adapt yield-from resume to optional generator frames

Coro.frame is now PyAtomicRef<Option<FrameObject>>, so the flattened
resume path uses frame_opt/clear_except_code instead of a direct frame.

Assisted-by: Grok:4.6

* Fix clippy and cr_origin after try_to_bool/f_lineno changes

try_to_bool now takes &self, so drop the leftover clones. Derive
cr_origin lines from lasti instead of prev_line, and satisfy
-Dwarnings on the immortal-refcount and del_needed types.

Assisted-by: Grok:4.6

* Convert fd filenames without the os ToPyObject impl

host_env-free builds (sandbox check, wasm) do not compile os.rs, so
OsPathOrFd::filename cannot use Borrowed's ToPyObject. Use as_raw()
instead, which is the same conversion.

Assisted-by: Grok:4.6

* Gate fd path helpers on the host_env feature

WASM clippy builds rustpython-vm without host_env, so OsPathOrFd and
the fspath/fd helpers are unused and fail -Dwarnings.

Assisted-by: Grok:4.6

* Drop redundant pickle try_to_bool clones after rebase

Assisted-by: Grok:4.6

* Document why enumerate keeps a Counter beside BigInt

Assisted-by: Grok:4.6

* Move fd path helpers into ospath_fd under host_env

Assisted-by: Grok:4.6

* Group threading eval-breaker bits in one module

Assisted-by: Grok:4.6

* Make InterpreterFrame construction unsafe

run_iframe stays safe: a live frame already has valid identity pointers.

Assisted-by: Grok:4.6

* Move OsPathOrFd re-export to the top of ospath.rs

Assisted-by: Grok:4.6

---------

Co-authored-by: Lee Dogeon <dev.moreal@gmail.com>
2026-09-20 00:32:26 +09:00
Jeong, YunWon 013333e5f9 host_env: keep Windows if_nameindex names as WTF-8 (#8742)
* host_env: keep Windows if_nameindex names as WTF-8

ConvertInterfaceLuidToNameW writes UTF-16; from_utf16_lossy replaced
unpaired surrogates with U+FFFD. Return Wtf8Buf from those units instead.

Assisted-by: Claude

* host_env: put if_nameindex wide test under cfg(test)

Windows clippy denies tests_outside_test_module for
cfg(all(test, windows)) modules.

Assisted-by: Claude
2026-09-19 23:21:20 +09:00
Jeong, YunWonandLee Dogeon 358f6a875a native _json, _pickle, pyexpat, and _elementtree (#8741)
* _json: add native make_encoder (c_make_encoder)

json.encoder fell back to the pure-Python _make_iterencode because _json
had no make_encoder, making json.dumps ~25x slower than CPython. Implement
the C encoder semantics natively: str/None/bool/int/float/list/tuple/dict
ordering, key coercion and skipkeys, sort_keys via the VM's fallible sort
(comparison errors propagate instead of panicking), circular reference
detection, indent handling, allow_nan, default() fallback with recursion
guard, and CPython's add_note annotations. Removes the now-passing
expectedFailure markers in test_json.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: add UseForeignDTD, fix silently swallowed handler exceptions

genshi's XML template loader (bm_genshi) called xmlparser.UseForeignDTD(),
which pyexpat.rs didn't implement, raising AttributeError. Add it as an
accepted no-op: the pyexpat module here wraps the pure-Rust xml-rs crate
(not real libexpat), which has no hook for splicing in a foreign DTD.

Root-causing the resulting bug also uncovered why genshi's template
generate()/render() produced empty output instead of erroring: do_parse's
invoke_handler swallowed every exception raised by a Python callback
(handler.call(...).ok()), and genshi's expat callbacks fail immediately
by reading `parser.CurrentLineNumber`/`CurrentColumnNumber`, which
pyexpat.rs never exposed. The AttributeError was silently discarded,
so no start/end/text events ever reached genshi's queue.

Fix both: propagate handler exceptions out of Parse()/ParseFile() (matching
libexpat/CPython semantics), and add CurrentLineNumber/CurrentColumnNumber/
CurrentByteIndex as read-only attributes backed by xml-rs's per-event
TextPosition (byte index is derived from it and is exact for ASCII
documents). This also fixes test_minidom's
testExceptionOnSpacesInXMLNSValue, previously an expected failure because
the ValueError from an invalid xmlns value was swallowed the same way.

PositionTest in test_pyexpat.py checks byte-exact expat semantics (token
*start* position) that xml-rs's *current parse cursor* position can't
reproduce exactly, so that one test is now marked an expected failure.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: support multi-chunk Parse()/ParseFile() feeds

bm_xml_etree failed with AssertionError: missing end tags from
TreeBuilder.close(), because xml.etree.ElementTree reads and feeds large
documents to XMLParser.feed() in ~64KB chunks (and xml.sax's
IncrementalParser and ElementTree's XMLPullParser do the same). Each
Parse()/ParseFile() call built a brand-new xml-rs EventReader from only
the bytes passed in that call, discarding all parser state between calls.
When a chunk boundary fell in the middle of an element, the fragment
parsed by itself was invalid/incomplete XML, so xml-rs silently errored
out (matching this module's existing "ignore stricter xml-rs errors"
behavior) and the corresponding start/end events were dropped entirely
-- not just delayed.

xml-rs has no API to resume a parser across separate Read sources, so
instead each call now appends the new chunk to a persistent buffer and
re-parses the buffer as a whole, replaying only the events at or beyond
the count already dispatched in previous calls (dispatched_events). This
also makes position tracking (CurrentLineNumber/Column/ByteIndex) correct
regardless of how the input was chunked. Trade-off: each Parse() call is
now O(size fed so far), so a document delivered in many small chunks is
parsed several times over; acceptable for correctness but noticeably
slower than a true incremental parser for pathological chunk sizes.

This also fixes several previously-xfailed tests that depend on
incremental feeding: test_xml_etree.py's XMLPullParserTest (test_events,
test_feed_while_iterating, test_simple_xml, test_simple_xml_chunk_22,
test_simple_xml_with_ns) and ElementTreeTest.test_parseliteral, plus
test_sax.py's ExpatReaderTest (test_expat_entityresolver_default,
test_expat_incremental, test_expat_incremental_reset) -- their
expectedFailure markers are removed. test_simple_xml_chunk_1/_chunk_5
(1- and 5-byte chunks) still fail and remain xfail: at that granularity
xml-rs's stricter-than-expat tokenizer errors on some intermediate
prefixes that libexpat tolerates.

Assisted-by: Claude Code:claude-fable-5-1

* test: drop stale expectedFailure markers fixed by the pyexpat changes

test_plistlib's four invalid-document tests and test_xmlrpc's
test_loads_unsupported pass now that pyexpat no longer swallows
handler exceptions and keeps parser state across chunked feeds.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: drive a single background EventReader for true incremental Parse()

8802451f3 fixed multi-chunk Parse()/ParseFile() feeds by accumulating every
fed byte and re-parsing the whole buffer from scratch on each call, which is
O(total bytes) per chunk -- quadratic in document size. xml-rs's EventReader
has no API to pause/resume across separate Read sources, so instead one
EventReader is now driven to completion on a dedicated background thread fed
through a condvar-backed queue (FeedBuffer/FeedReader); Parse()/ParseFile()
push their chunk, wake the thread, and drain (on the calling thread only)
whatever events that unblocks, stopping once the thread reports it is
blocked waiting for more input. Handlers always run on the calling thread.
A handler exception stops dispatch without tearing down the stream, so the
next Parse() resumes where it left off, mirroring libexpat. CurrentByteIndex
is now computed incrementally per line (with an amortized per-query cursor,
needed since real documents are often a single very long line) instead of
scanning the whole buffer. ParserCreate() never spawns a thread; one is
spawned lazily by the first Parse()/ParseFile() call, and dropping the
parser always stops and joins it.

Fixes test_xml_etree{,_c}'s test_events_comment, previously xfailed because
the old whole-buffer replay lost top-level comment events across feeds.

Measured (M4 Pro, release build):
- Scaling (ElementTree.parse, newline-separated doc): new backend 1/4/16 MB
  = 0.15/0.61/2.35s (linear); CPython 3.14 same file = 0.015/0.055/0.23s.
- pyperformance's bm_xml_etree doc (156KB, effectively one line): old
  backend single etree.parse() = 1.99s, single iterparse() = 3.53s; new
  backend = 0.025s / 0.031s (~80-110x). Full bench_parse/iterparse/generate/
  process (30/10/10/1 reps) now finish in ~1.5s/0.6s/0.4s/0.3s instead of
  timing out past pyperformance's 400s limit.
- 10k ParserCreate() (never fed / partially fed / fully fed and dropped):
  0.32s, no residual native threads, no RSS growth.

test -j4 test_pyexpat test_xml_etree test_xml_etree_c test_sax test_minidom
test_xml_dom_minicompat test_pulldom test_plistlib test_xmlrpc test_html
test_htmlparser test_threading: all pass (1350 tests, 89 skipped).

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: add a Sync fallback backend for targets without threads

2f58e9531 made pyexpat always drive its EventReader on a background
thread (ParserStream::spawn), panicking via .expect() if the thread
couldn't be spawned. pyexpat is registered unconditionally, including
on wasm32, where std::thread::spawn always fails at runtime, so the
first Parse() call panicked there.

Introduce a Backend enum: Backend::Threaded (the existing ParserStream)
on targets that can spawn threads, and a new Backend::Sync, the
accumulate-and-reparse implementation from 8802451f3, used on wasm32
and as a runtime fallback if spawning a thread ever fails. Both share
LineTracker for identical CurrentLineNumber/CurrentColumnNumber/
CurrentByteIndex and handler/error semantics.

Fixed two correctness bugs while porting the Sync backend forward:
marking the parser permanently "finished" as soon as a from-scratch
reparse happened to reach EndDocument (which can be a false positive
on a not-yet-complete buffer, e.g. right before epilog content
arrives) rather than only on the caller's real isfinal signal; and
counting that same EndDocument towards the dispatched-event index,
which could make a real event land on an index a later, longer reparse
had already skipped past. Verified by force-selecting Backend::Sync
under a test-only env var (removed) and diffing its output against
Backend::Threaded for the xml/sax/etree/plistlib/xmlrpc test suites
and a 2MB document fed in 1KB chunks.

Assisted-by: Claude Code:claude-fable-5-1

* _pickle: native Pickler, Unpickler and PickleBuffer

Adds `crates/stdlib/src/pickle.rs`, a native `_pickle` implementing
Pickler, Unpickler, PickleBuffer, PicklerMemoProxy/UnpicklerMemoProxy,
dump/dumps/load/loads and the PickleError family, so `Lib/pickle.py`
stops falling back to `_Pickler`/`_Unpickler`.

Protocols 0-5 are supported and produce byte-identical output to the
pure-Python pickler, including framing for protocol >= 4, memoization,
`fast` mode, dispatch_table, reducer_override, persistent_id /
persistent_load, find_class with `_compat_pickle` fix_imports, buffer
callbacks and out-of-band protocol 5 buffers. This also turns on
`pickle.PickleBuffer`, which RustPython did not have before.

Speedups over the pure-Python implementation (best of 5, us/op):
pickle 835 -> 21 (39x), pickle_list 525 -> 4.4 (119x),
pickle_dict 4018 -> 32 (125x), unpickle 630 -> 24 (26x),
unpickle_list 317 -> 5.0 (63x). CPython 3.14's C accelerator runs the
same workloads 1.5-2.9x faster than this.

test_pickle now runs 1008 tests (was 470) since the C-implementation
test classes are enabled; test_pickle, test_pickletools,
test_picklebuffer are green and 22 obsolete expectedFailure markers are
removed.

Assisted-by: Claude Code:claude-fable-5-1

* _pickle: raise the pickle.find_class audit event

Unpickler.find_class now raises `sys.audit('pickle.find_class', module,
name)` like CPython, so audit hooks can veto global lookups
(test_audit.test_pickle). Also drops four expectedFailure markers that
the native module makes pass: test_pydoc's builtin-method description
tests, test_memoryview.test_picklebuffer_reference_loop and
test_pyclbr.test_others.

Full suite: 456 test files / 42,648 tests green.

Assisted-by: Claude Code:claude-fable-5-1

* _pickle: avoid temporary buffers on the save fast paths

Opcode plus payload is now appended straight to the output buffer
(`write_pair`) instead of building a `Vec` per int, str, bytes and memo
opcode, `save_tuple` no longer copies the element slice, and the
`when serializing ...` note text is only formatted when an error is
actually raised.

bm_pickle "pickle" workload: 21.4 -> 17.0 us/op.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: make the threaded backend fork-safe

fork() only keeps the calling thread. test_platform's
test_mac_ver_with_fork crashed the child with SIGTRAP: plistlib parses
a plist through pyexpat (spawning a background parser thread) before
os.fork(), then parses again in the child. Bisecting away every other
explanation (a plain threading.Thread survives the same fork fine,
since it goes through this VM's own fork-safe thread bookkeeping)
showed the crash is not from touching the *inherited* ParserStream
(already joined by refcounting before the fork in this repro) but from
spawning a *brand new* parser thread from the child, which reliably
crashed during the new thread's own startup.

Register a pthread_atfork child hook (lazily, the first time a parser
thread is spawned) that sets a permanent, process-wide flag the
instant this process is ever the child of a fork(). Once set:
- ParserStream::try_spawn refuses to spawn any further thread and
  Backend::new falls back to Backend::Sync instead, exactly as on
  targets that cannot spawn threads at all.
- Feeding an inherited Backend::Threaded raises a clear ExpatError
  instead of touching its FeedBuffer/channel (whose mutex/condvar may
  look held by a thread that no longer exists), and dropping it leaks
  its JoinHandle/buffer/channel via ManuallyDrop rather than joining or
  destroying them, since even destroying a POSIX mutex that looks held
  is undefined behavior.

The parent is unaffected: the pthread_atfork hook only runs in the
child. Verified with a 200-iteration fork stress test (fresh parsers
and parsers forked mid-parse) and the full test_platform/xml/fork/
subprocess/multiprocessing_fork test modules.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: implement name interning via self.intern, matching libexpat

self.intern (an always-present dict by default) was stored but never
consulted; every StartElement/EndElement/attribute name allocated a
fresh PyStr even when the same tag or attribute name repeated across
many sibling events. Wire it up the way libexpat does
(PyDict_SetDefault(self->intern, name, name)): element and attribute
*names* are now memoized so a repeated name reuses the same PyStr
object (and its cached hash) instead of reallocating and rehashing.
Attribute values are left out of the cache, same as libexpat.

This fixes test_pyexpat's previously-xfailed InterningTest.test, which
asserts object identity across repeated StartElementHandler/
EndElementHandler calls.

Measured on the pyperformance xml_etree parse/iterparse/generate/
process variants: no measurable wall-clock change (the dominant cost
there is Python-level TreeBuilder/Element bytecode execution and
thread hand-off, not name allocation), so this is a correctness/
feature-completion fix rather than a throughput win for that
benchmark; kept because it is a real, previously-inert compatibility
gap and is otherwise free.

Assisted-by: Claude Code:claude-fable-5-1

* _elementtree: native Element, SubElement and ParseError

Adds crates/stdlib/src/elementtree.rs providing the accelerator names
xml/etree/ElementTree.py picks up at import time. Element carries the
full API (tag/text/tail/attrib, indexing and slicing, find*/iter/
itertext, copy/deepcopy/pickle state) with CPython's lazily created
attrib dict and deferred text join, is subclassable, weak-referenceable
and GC-traversable, and drops every displaced object after releasing its
lock so a __del__ can re-enter safely.

xml_etree, best of 3 (s): parse 1.64 -> 1.14, iterparse 0.68 -> 0.54,
generate 0.44 -> 0.25, process 0.27 -> 0.16.

Assisted-by: Claude Code:claude-fable-5-1

* _elementtree: native TreeBuilder and XMLParser

TreeBuilder keeps CPython's element/data/tail bookkeeping in Rust,
including the pull-parser event hooks _setevents installs. XMLParser
drives a pyexpat parser whose handlers are this type's own native
methods, so a start or end tag reaches the builder without a Python
frame: the universal-name cache, attribute dict and TreeBuilder call all
happen in Rust when the target is our own builder, while foreign targets
still go through the documented start/end/data/comment/pi protocol.
ElementTree.parse() also picks up the _parse_whole fast path.

xml_etree, best of 3 (s): parse 1.14 -> 0.53, iterparse 0.54 -> 0.28,
generate 0.25 -> 0.24, process 0.16 -> 0.16. Against the pure-Python
baseline that is parse 3.1x, iterparse 2.4x, generate 1.8x, process
1.7x.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: stop rescanning the whole line per position query

LineTracker converted a TextPosition column to a byte offset by
validating and decoding its entire buffered line tail on every query,
and appended fed bytes to that tail one at a time. On a document that is
one long line -- what xml.etree.tostring() writes, and what the
xml_etree benchmark parses -- the tail is the whole read-ahead, so a
per-event lookup became quadratic. Walk only the characters the query
actually asks for, over the deque's two halves in place, and record fed
bytes a line at a time. Byte indices are unchanged.

xml_etree, best of 3 (s): parse 0.52 -> 0.38, iterparse 0.28 -> 0.25.

Assisted-by: Claude Code:claude-fable-5-1

* _elementtree: charge Element.__deepcopy__ to the recursion budget

A chain of elements is copied by native recursion, so a deep enough tree
overflowed the real stack instead of raising. Wrap the copy in
with_recursion, as CPython does, and drop the skip on
test_deeply_nested_deepcopy for the accelerated run.

Assisted-by: Claude Code:claude-fable-5-1

* pyexpat: don't let a stale NeedMore end a Parse() early

The parser thread reports NeedMore when it finds the feed buffer empty
and parks. If it reached that point before the chunk Parse() was about
to push became visible -- which it does whenever the thread happens to
be scheduled first, so more often under load -- pump() consumed that
report as if it answered the new chunk and handed control back to Python
having dispatched nothing, silently losing the whole document.

Stamp each NeedMore with the push count observed when the buffer was
found empty and ignore reports older than the push being pumped. The
push notifies the condvar under the same mutex the report was sent
from, so the parser thread is guaranteed to wake and report again.

Fixes an intermittent failure of test_pyexpat's InterningTest under
parallel load (about 5 losses per 20000 parses before, none after).

Assisted-by: Claude Code:claude-fable-5-1

* Restore xml.etree test markers instead of skipTest in bodies

Assisted-by: Grok:4.6

* Clone state before try_to_bool in pickle load_build

try_to_bool takes the object by value, and load_build still needs the
state dict afterwards.

Assisted-by: Grok:4.6

* Drop decorative section-separator comments

Assisted-by: Grok:4.6

* Represent pickle opcodes as an enum

Assisted-by: Grok:4.6

* Use full paths for thread-only types in pyexpat

Assisted-by: Grok:4.6

---------

Co-authored-by: Lee Dogeon <dev.moreal@gmail.com>
2026-09-19 19:21:32 +09:00
Jeong, YunWon 6d39d132d8 Keep SemLock OS calls behind SemHandle methods (#8740)
Stop exporting libc semaphore pointers from host_env. Stdlib
now waits, posts, and reads values through SemHandle instead
of *mut sem_t / HANDLE.

Assisted-by: Grok:4.6
2026-09-19 18:11:14 +09:00
Jeong, YunWon 0bdb61bfb6 Serialize SemLock bookkeeping for Condition notify (#8739)
* Serialize SemLock owner bookkeeping around waits

Hold a mutex around SemLock acquire/release/_count so the
per-object owner count cannot tear while threads and
processes share a Condition. Drop the mutex only for the
blocking wait.

Mark Unix SemHandle Send/Sync. Add a spawn
Condition.notify_all snippet.

Assisted-by: Grok:4.6

* Repeat the Condition.notify_all snippet 20 times

Give the snippets job more chances to see a lost wakeup.

Assisted-by: Grok:4.6

* Cover one-by-one Condition.notify in the snippet

Wake a process waiter and a thread waiter with two notify()
calls, not only notify_all(), and keep the 20-repeat loop.

Assisted-by: Grok:4.6

* address review: bound snippet waits with timeouts

Assisted-by: Grok:4.6
2026-09-19 15:19:57 +09:00
Jeong, YunWon a7c0500a42 host_env: export remaining Windows socket and fault constants (#8736)
* host_env: export remaining Windows socket and fault constants

Publish AF_HYPERV/AF_BLUETOOTH, HV_* GUIDs, SIO_TCP_SET_ACK_FREQUENCY,
EXCEPTION_CONTINUE_SEARCH, and winreg ERROR_FILE_NOT_FOUND/INVALID_DATA.
os.socket pack/unpack Hyper-V and RFCOMM addresses through host_env.

Assisted-by: Claude

* socket: publish HV_GUID_* as string attributes

Assisted-by: Claude

* host_env: cast SIO_TCP_SET_ACK_FREQUENCY to i32

The WinSock constant is u32 and does not fit i32 without a wrapping
cast. Socket module attributes are i32.

Assisted-by: Claude

* socket: use socklen_t width for Windows SockAddr::new

Windows socklen_t is i32; a u32 cast does not match socket2.

Assisted-by: Claude

* socket: drop unused Windows AF_* imports from c

AF_BTH, AF_IRDA, and AF_SNA are published via host_socket pyattr
and are not read through the Windows c alias module.

Assisted-by: Claude

* host_env: export Windows faulthandler exception codes

Route stdlib _EXCEPTION_* pyattrs and exception_description
through named host_env constants instead of hex literals.

Assisted-by: Claude
2026-09-19 15:18:00 +09:00
Jeong, YunWon 0c5a47bae5 Unskip MP tests and shrink the flaky MP CI list (#8731)
* Unskip multiprocessing RLock repr test

Assisted-by: Grok:4.6

* Drop stable modules from the flaky MP CI list

Assisted-by: Grok:4.6

* Keep only multiprocessing fork on the flaky MP list

Assisted-by: Grok:4.6

* Drop gc_collect bench and unbreak two CI jobs

Remove benches/benchmarks/gc_collect.py so CodSpeed no longer
includes that execution benchmark.

On Windows, run test_multiprocessing_spawn serially; the
parallel snippets job hit a regrtest worker temp-dir error
while that suite was still running.

Install cargo-shear from a pinned prebuilt binary so the job
does not fall back to compiling 1.13.4 from source.

Assisted-by: Grok:4.6

* Unskip hang tests that now pass under -m test

Drop the RustPython hang skips on interpreter shutdown,
submit-after-shutdown, and connection pickling after they
passed with rustpython -m test.

Remove the unused expectedFailureIf around killpg on the
resource tracker deadlock test; os.killpg is present.

Pass matrix flaky-MP extras through the job environment
instead of interpolating them into the run script.

Assisted-by: Grok:4.6

* Restore hang skips and isolate spawn on CI

Put test_multiprocessing_spawn and
test_multiprocessing_forkserver back on the serial flaky MP
list. Ubuntu timed out in spawn test_notify_all under -j, and
forkserver.test_processes needed a rerun.

Restore the hang skips on interpreter shutdown, submit-after
shutdown, and connection pickling.

Assisted-by: Grok:4.6
2026-09-19 10:38:05 +09:00
Jeong, YunWon 73a3f45ee4 host_env: add Windows FindFirstFileW scandir walk (#8734)
* host_env: add Windows FindFirstFileW scandir walk

nt::scandir walks with FindFirstFileW/FindNextFileW and yields
WIN32_FIND_DATA fields. os.scandir uses it on Windows instead of
std::fs::ReadDir.

Assisted-by: Claude

* host_env: store scandir find handle as isize

HANDLE is a raw pointer and is not Sync, so Scandir could not sit
in the os.scandir iterator lock. Store the handle as isize.

Assisted-by: Claude

* address review: is_dir skips directory symlinks

Windows DirEntry.is_dir used FILE_ATTRIBUTE_DIRECTORY whenever
follow_symlinks was false, so a directory symlink reported true.
A directory symlink is not a directory unless it is followed.
Junctions stay on the find-data bit; they are not symlinks.

Assisted-by: Claude
2026-09-19 10:25:40 +09:00
Jeong, YunWon b2c48d3ab4 Keep specialized CALL under Return/Unwind events (#8735)
* Keep specialized CALL under Return/Unwind events

Instrument only opcodes whose EVENT_FOR_OPCODE is active so
CALL_ALLOC_AND_ENTER_INIT survives Return+Unwind. LINE and
INSTRUCTION still restore every specialized opcode. FOR_ITER
RAISE/STOP_ITERATION consult the global event mask.

Assisted-by: Grok:grok-4.6

* Fix frame repr, f_lineno delete, and class cell timing

frame.__repr__ matches the C format. Deleting f_lineno raises
AttributeError. __classcell__ is filled before a custom mro()
so methods that close over __class__ can run during type creation.

Assisted-by: Grok:grok-4.6
2026-09-19 10:24:57 +09:00
Jeong, YunWon faa5a60638 host_env: bound symlink probe; add Win32 times (#8733)
nt::symlink's directory probe now uses two WCHAR[MAX_PATH]
buffers and treats an overflowing join as not a directory.
winapi::version_ex_triple exposes GetVersionExW. nt::set_file_times
opens with FILE_WRITE_ATTRIBUTES and writes wrapping FILETIMEs.

Assisted-by: Claude
2026-09-19 00:44:17 +09:00
Jeong, YunWon 300d8bdc02 Honor inline values, custom mro, and type lookup (#8729)
* Add inline values flags and special-method lookup

lookup_maybe_method clears AttributeError from descr_get.
slot_tp_richcompare treats a miss as NotImplemented.
hackcheck rejects object.__setattr__ on types.
Heap types with a managed dict and itemsize 0 get
INLINE_VALUES; _testinternalcapi.has_inline_values
reports the valid bit.
super is a base type; subclass __get__ binds the instance.
__classcell__/__qualname__ may share a name with a slot.
Unset member access uses the type's fully qualified name.

Assisted-by: Grok:grok-4.6

* Call custom mro and descr_get for type.__new__

type.mro() computes C3 from the current bases.
A metaclass other than type supplies the MRO via mro().
super() compares obj.__class__ to the instance type.
slot_tp_new looks up __new__ through descr_get.
is_subtype walks the stored MRO without an identity shortcut.
__slots__ names are sorted so __class__ assignment matches.

Assisted-by: Grok:grok-4.6

* Expose _testinternalcapi recursion and rare events

get_recursion_depth feeds test.support.infinite_recursion.
SPECIALIZATION_* and SHARED_KEYS_MAX_SIZE match the
adaptive counters. Rare-event hooks increment on
__class__/__bases__/function/builtins writes.

Assisted-by: Grok:grok-4.6

* Add remaining _testinternalcapi code and locale APIs

Expose get_co_localskinds, get_code_var_counts, verify_stateless_code,
code_returns_only_none, normalize_path, EncodeLocaleEx, DecodeLocaleEx,
and run_in_subinterp_with_config. Mark unimplemented compiler IR and
specialization monitoring tests as expectedFailure.

Assisted-by: Grok:grok-4.6

* Fix lint for _testinternalcapi identifiers

Add CPython identifier spellings to the cspell dictionary and apply
the rustfmt signature that CI rewrote.

Assisted-by: Grok:grok-4.6

* Expand _testinternalcapi with remaining test APIs

Add constants, compiler_cleandoc, dict_getitem_knownhash, time
helpers, interpreter/frame accessors, configs, static types, a
persistent hamt map, and GC/size counters used by the test suite.

Assisted-by: Grok:grok-4.6

* Expose compiler IR APIs in _testinternalcapi

Add InstructionSequence and compiler_codegen, optimize_cfg, and
assemble_code_object. Drop expectedFailure marks on tests that pass.

Assisted-by: Grok:grok-4.6

* Match optimize_cfg consts and addop locations

Write optimized consts back into the caller's list, mark SETUP_*
pseudo-ops as having an argument, and store addop locations in
instruction-sequence field order. Drop expectedFailure marks on
tests that pass.

Assisted-by: Grok:grok-4.6

* Fix hamt API, SETUP_* HAS_ARG, and FOR_ITER events

Honor explicit pseudo flags when generating opcode metadata so
SETUP_FINALLY/CLEANUP/WITH keep HAS_ARG after regeneration.

Complete the _testinternalcapi hamt mapping: identity on
set/delete, richcompare, weakrefs, subscript, contains, and
length-bearing iterators.

Fire RAISE/STOP_ITERATION for FOR_ITER StopIteration, and skip
both END_FOR and POP_ITER for the exhausted-branch destination.

Assisted-by: Grok:grok-4.6

* Skip FOR_ITER RAISE for sequence iterators

List/range/tuple exhaustion matches FOR_ITER_LIST/RANGE/TUPLE and
must not emit a monitoring RAISE. That event stopped pdb's
monitoring backend on for-over-list with Internal StopIteration.

Assisted-by: Grok:grok-4.6

* Fix generator FOR_ITER events and review issues

Restore settrace StopIteration for generator for-loops so
test_bdb next/return cases pass, while sequence iterators still
skip RAISE.

Honor review notes: addop oparg bounds, linetable locations,
AST instance errors, MRO subclass lock, builtin-dict notify,
direct-base layout flags, and leftover _testinternalcapi args.

Assisted-by: Grok:grok-4.6
2026-09-19 00:40:20 +09:00
Jeong, YunWon 982cbd4d25 Add os.wait3 and os.wait4 with EINTR retry (#8728)
* Add os.wait3 and os.wait4 with EINTR retry

Assisted-by: Grok:4.6

* Unskip multiprocessing Finalize thread-safety test

Assisted-by: Grok:4.6

* Fix wait4 clippy lint and use libc wait4

Assisted-by: Grok:4.6
2026-09-18 11:03:46 +09:00