1707. CPython 3.14.5 sync

Why this spec exists

Gopy's "behavioural compatibility with CPython 3.14" claim is only as fresh as the upstream tree we last referenced. Two CPython clones live on this machine:

• $HOME/cpython-314 is the canonical read-only mirror used by the port specs (every // CPython: citation resolves against this tree).
• $HOME/github/python/cpython is the working clone used to cherry-pick patches and reproduce upstream tests.

Both were behind the v3.14.5 release tag (cut 2026-05-10). The brew formula python@3.14 was also pinned at 3.14.4. On 2026-05-14 all three were bumped to v3.14.5:

Target	Before	After
/opt/homebrew/Cellar/python@3.14	3.14.4_1	3.14.5
$HOME/cpython-314 HEAD	c235654cba2 (2026-04-20)	5607950ef23 (v3.14.5)
$HOME/github/python/cpython HEAD	ab2d84fe102 (2026-04-29)	5607950ef23 (v3.14.5)

The v3.14.4 → v3.14.5 window covers 56 first-parent commits and touches 257 files. The Lib/, Modules/, Objects/, Python/ subtrees account for 89 of those; the rest are docs, CI, installer, and test files. This spec catalogues the 89 that gopy cares about and breaks them down by whether gopy has a port that needs a refresh.

Rule

Every CPython upstream change that affects a file gopy already ships a port for (whether a Go translation under module/ or a byte-equal vendor under stdlib/) is treated as a refresh task on this spec. We do not skip patches because they are "small" or "cosmetic". A two-line upstream fix that changes user-visible behaviour is still a divergence if we don't apply it.

A row gets ticked off when:

1. The gopy port has the upstream fix mirrored (Go code or re-vendored .py).
2. The accompanying CPython test (or a gopy equivalent) runs green under gopy.

Sync workflow

# refresh both clones to the next 3.14.x tag
git -C $HOME/cpython-314 fetch --tags origin 3.14
git -C $HOME/cpython-314 checkout v3.14.<n>
git -C $HOME/github/python/cpython fetch --tags origin 3.14
git -C $HOME/github/python/cpython checkout v3.14.<n>

# brew (optional, only matters when running upstream's own tests)
brew upgrade python@3.14

# audit
git -C $HOME/github/python/cpython diff --stat v3.14.<n-1>..v3.14.<n> -- \
  'Lib/' 'Modules/' 'Objects/' 'Python/' 'Include/'

# for each changed file, decide: gopy has a port -> add a row below.

Files in scope

The 89 runtime files that changed between v3.14.4 and v3.14.5 fall into four buckets. Each table below lists the upstream file, the gopy port (if any), the upstream bug + summary, and the work required in gopy.

A. Python stdlib refreshes (stdlib/ vendor)

Gopy vendors most of these byte-equal. A refresh means re-copying the upstream .py into stdlib/ and re-running the relevant gate test.

#	Upstream file	gopy target	Upstream change	Status
A.1	Lib/argparse.py	stdlib/argparse.py	GH-130750: _check_value quotes each choice via repr(str(choice)) instead of the bare comma-joined form. Error message went from invalid choice: 'x' (choose from a, b) to invalid choice: 'x' (choose from 'a', 'b').	pending
A.2	Lib/annotationlib.py	stdlib/annotationlib.py	gh-141388: handle non-function callables as annotate functions. Adds __wrapped__ traversal and _check_no_unevaluated_strings accommodations for partial, lambda, etc. (36 lines). Sister to spec 1706.	pending
A.3	Lib/configparser.py	stdlib/configparser.py	17 lines of edge-case fixes.	pending
A.4	Lib/dataclasses.py	stdlib/dataclasses.py (or port at module/dataclasses/)	26 lines of bug fixes. Note: gopy ports dataclasses as Go (module/dataclasses/), not vendored. Audit + apply behaviour parity.	pending
A.5	Lib/inspect.py	not vendored (audit only)	Docstring change removes im_* reference (gh-149096). No behavioural impact.	n/a
A.6	Lib/pickle.py	not vendored (no gopy port)	gh-148914: fix PickleBuffer memoization of in-band buffers. Tracked under future pickle port.	n/a
A.7	Lib/random.py	stdlib/random.py	gh-149221: sync random.py with main; gh-149276: fix binomialvariate for the n=1 edge case. Re-vendor + add the new tests as a gopy gate.	pending
A.8	Lib/runpy.py	not vendored	gh-149117: set ImportError.name from runpy.run_module/run_path. Tracked under future runpy port.	n/a
A.9	Lib/shutil.py	stdlib/shutil.py	24 lines. Re-vendor.	pending
A.10	Lib/typing.py	not vendored (no gopy port)	gh-149221-adjacent: get_type_hints now detects __wrapped__ loops and raises ValueError. Tracked under future typing port.	n/a
A.11	Lib/urllib/robotparser.py	stdlib/urllib/robotparser.py (if vendored)	gh-138908: RFC 9309 support. 209 lines of new behaviour: wildcard handling, group precedence, longest-match. If gopy ships robotparser, re-vendor.	pending
A.12	Lib/uuid.py	stdlib/uuid.py	10 lines. Re-vendor.	pending
A.13	Lib/zipfile/__init__.py	stdlib/zipfile/__init__.py	21 lines. Re-vendor.	pending
A.14	Lib/timeit.py	stdlib/timeit.py (if vendored)	2 lines.	pending
A.15	Lib/webbrowser.py	not vendored	5 lines.	n/a
A.16	Lib/socket.py	stdlib/socket.py (if vendored)	28 lines.	pending
A.17	Lib/http/client.py, Lib/http/cookies.py	stdlib/http/	11 + 8 lines respectively.	pending
A.18	Lib/email/_header_value_parser.py, Lib/email/generator.py, Lib/email/quoprimime.py	stdlib/email/	15 + 2 + small. bpo-39100 _header_value_parser no longer treats Group as invalid mailbox.	pending
A.19	Lib/smtplib.py	not vendored	2 lines.	n/a
A.20	Lib/pdb.py	not vendored	gh-148615: handle -- separator in argument parsing.	n/a
A.21	Lib/json/tool.py	not vendored	3 lines.	n/a
A.22	Lib/multiprocessing/* (connection.py, popen_fork.py, resource_tracker.py)	not vendored	small fixes.	n/a
A.23	Lib/asyncio/__main__.py, Lib/asyncio/windows_utils.py	not vendored	gh-149388: PipeHandle.close idempotent.	n/a
A.24	Lib/ensurepip/__init__.py + bundled wheel	not vendored	gh-149148: bump bundled pip from 26.0.1 to 26.1.1.	n/a

B. C modules (module/ Go port)

#	Upstream file	gopy target	Upstream change	Status
B.1	Modules/_csv.c	module/_csv/	6 lines. Audit for behaviour change.	pending
B.2	Modules/_struct.c	module/_struct/	gh-148675: add Zd, Zf, Zg, Ze complex format codes (27 lines). Add to gopy's format table. Linked to arraymodule.c and memoryobject.c.	pending
B.3	Modules/arraymodule.c	gopy array module (none yet)	gh-148675: Zd/Zf complex formats (10 lines).	pending
B.4	Modules/binascii.c	gopy binascii (none)	gh-148093: a2b_uu raises binascii.Error on empty input (8 lines).	n/a
B.5	Modules/gcmodule.c	module/gc/	30 lines. Knock-on from Python/gc.c generational restoration: new gc.get_stats fields, heap_size in stats. Sync the gc module's getset table.	pending
B.6	Modules/zlibmodule.c	module/zlib/	1 line cleanup.	pending
B.7	Modules/_elementtree.c	gopy XML (none)	45 lines.	n/a
B.8	Modules/_asynciomodule.c	gopy asyncio (none)	6 lines.	n/a
B.9	Modules/_bz2module.c, Modules/_lzmamodule.c, Modules/_zstd/*	gopy (none)	compression cleanups.	n/a
B.10	Modules/_ctypes/_ctypes.c, Modules/_ctypes/cfield.c	gopy ctypes (none)	gh-148675 (Zd/Zf) + gh-148967 (C complex FFI fix).	n/a
B.11	Modules/_remote_debugging_module.c	none	3.14 debugger surface; not in gopy scope.	n/a
B.12	Modules/overlapped.c	none	Windows IO.	n/a
B.13	Modules/expat/*	gopy (none, uses Go's encoding/xml)	gh-149698: bundled expat bumped to 2.8.1.	n/a

C. Object protocol (objects/ Go port)

#	Upstream file	gopy target	Upstream change	Status
C.1	Objects/codeobject.c	objects/code.go and friends	24 lines. Code-object internal cleanups; audit co_* field churn.	pending
C.2	Objects/dictobject.c	objects/dict.go	4 lines. Free-threading lock cleanup.	pending
C.3	Objects/genericaliasobject.c	objects/genericalias.go	3 lines.	pending
C.4	Objects/memoryobject.c	objects/memoryview.go	gh-148675: Zd/Zf complex formats; gh-148390: fix UB in memoryview(...).cast("?"). 8 lines.	pending
C.5	Objects/object.c	objects/object.go and ports/	8 lines. Audit per the 1704 full-port rule.	pending
C.6	Objects/typevarobject.c	objects/typevar.go	9 lines.	pending
C.7	Objects/unicodeobject.c	objects/str.go and friends	56 lines. Three independent fixes: (a) gh-113956: thread-safe intern_common in free-threaded build; (b) gh-147856: bytes.replace() accepts count as a keyword; (c) GH-145668: FOR_ITER specialization for virtual iterators (also touches Python/bytecodes.c). Only (b) is observable from gopy.	pending

D. VM / compile (vm/, compile/, module/builtins/)

#	Upstream file	gopy target	Upstream change	Status
D.1	Python/bltinmodule.c	module/builtins/	10 lines. Audit for behaviour change.	pending
D.2	Python/bytecodes.c	vm/ opcodes	20 lines. Two fixes: (a) gh-137030: YIELD_VALUE assert no longer crashes on instr_ptr reads when the executable is detached; (b) gh-137814: MAKE_FUNCTION_ANNOTATE rewrites the qualname of the __annotate__ function to <parent>.__annotate__. The annotate-qualname fix is on the gopy hot path because spec 1706 just landed; verify our MAKE_FUNCTION_ANNOTATE op sets func_qualname the same way.	pending
D.3	Python/codegen.c	compile/codegen_*.go	9 lines. Two fixes: (a) gh-149122: refleak in codegen; (b) maybe_optimize_function_call now bails out when the generator expression is a coroutine (otherwise the genexp-to-fast-call fold would be wrong). The coroutine guard is observable: a [x async for x in ...] inside list(...) no longer mis-compiles. Re-check compile/codegen_call_optim.go.	pending
D.4	Python/compile.c	compile/ driver	14 lines.	pending
D.5	Python/flowgraph.c	compile/flowgraph_*.go	146 lines. Cleanups and one bug fix in inline_small_or_no_lineno_blocks. Audit gopy's flowgraph.	pending
D.6	Python/gc.c	module/gc/ + Go runtime	gh-148726: forward-port the generational GC to 3.14 (1076 lines, 330 ins / 746 del, mostly a refactor that re-introduces young/middle/old generations after 3.13's "incremental GC" experiment). gopy's GC is Go's runtime, not a Python-side mark/sweep, so most of this is informational; however, gc.get_stats(), gc.get_count(), gc.collect(generation=...), gc.set_threshold, gc.get_threshold, and gc.freeze/gc.unfreeze are observable from Python and need consistent return shapes. Audit module/gc/.	pending
D.7	Python/instrumentation.c	vm/instrumentation.go (if ported)	41 lines. Tracking gh-148178 (validate remote debug offset tables). Mostly debugger surface.	pending
D.8	Python/legacy_tracing.c	not ported	4 lines.	n/a
D.9	Python/marshal.c	gopy marshal (none)	gh-148418: reference leak on corrupted TYPE_CODE stream (46 lines). Tracked when marshal lands.	n/a
D.10	Python/optimizer_analysis.c	gopy tier-2 optimizer	5 lines.	pending
D.11	Python/crossinterp.c, Python/parking_lot.c, Python/lock.c	not ported	free-threading internals.	n/a
D.12	Python/executor_cases.c.h, Python/generated_cases.c.h	derived	auto-generated; reflects bytecodes.c changes.	n/a

Highlights: patches gopy must land soon

Pulled out separately because the rest of the table is sortable maintenance work; these are the items that change observable behaviour for code gopy already runs:

1. MAKE_FUNCTION_ANNOTATE qualname rewrite (D.2 gh-137814). Spec 1706 just landed the deferred-annotation pipeline. The 3.14.5 fix means f.__annotate__.__qualname__ is now <parent>.__annotate__ instead of inherited from the function slot. Without this fix, inspect.signature and typing.get_type_hints reporting will diverge.

2. argparse choice quoting (A.1 GH-130750). One-line re-vendor; the error message is part of unittest gates.

3. Lib/annotationlib.py non-function callables (A.2 gh-141388). Spec 1706 Phase 8 just shipped this file byte-equal; we need a re-vendor against v3.14.5 to keep the annotate-callable handling in sync (partial, lambda, decorator-wrapped callables).

4. bytes.replace(count=…) keyword (C.7 gh-147856). Tests in test_bytes will fail without this.

5. codegen.c coroutine genexp guard (D.3). If gopy ports maybe_optimize_function_call, the guard prevents a mis-compile of list(x async for x in agen).

6. gcmodule.c / Python/gc.c generational GC API (B.5, D.6). gc.get_stats() schema changed (now includes heap_size, per-generation counts). gopy's module/gc/ returns its own shape; align with 3.14.5 fields so vendored code (e.g., Lib/test/test_gc.py) compiles.

7. struct/array/memoryview complex format codes (B.2, B.3, C.4 gh-148675). Zd (complex128), Zf (complex64), Zg, Ze join the existing format chars. gopy's module/_struct/ table currently rejects them.

Files explicitly out of scope

These changed upstream but gopy does not ship a port, so they are tracked only for future reference:

• Lib/pickle.py, Lib/typing.py, Lib/runpy.py, Lib/inspect.py, Lib/pdb.py, Lib/json/tool.py, Lib/multiprocessing/*, Lib/asyncio/*, Lib/ensurepip/*
• Modules/binascii.c, Modules/_elementtree.c, Modules/_asynciomodule.c, Modules/_bz2module.c, Modules/_lzmamodule.c, Modules/_zstd/*, Modules/_ctypes/*, Modules/_remote_debugging_module.c, Modules/overlapped.c, Modules/expat/*
• Python/marshal.c, Python/crossinterp.c, Python/parking_lot.c, Python/lock.c, Python/legacy_tracing.c
• All Windows/Apple/Android installer files
• All Lib/test/* files (we maintain our own gate corpus under spec 1701)
• Doc/, .github/workflows/, iOS/, Mac/, PCbuild/, Tools/

Gate

This spec is done when every row marked pending above is either flipped to done (port refreshed + matching test green) or moved to an explicit out-of-scope follow-up with a tracking issue. The audit cadence is per-release: every new 3.14.x tag spawns a fresh 1707_X follow-up spec (e.g., 1707_3146.md) with the v3.14.5 → v3.14.6 delta. The structure above is the template.

Checklist

• Pull $HOME/cpython-314 to v3.14.5 tag.
• Pull $HOME/github/python/cpython to v3.14.5 tag.
• Upgrade brew python@3.14 from 3.14.4_1 to 3.14.5.
• Audit git diff --stat v3.14.4..v3.14.5 for Lib/, Modules/, Objects/, Python/, Include/.
• Bucket each touched file into Stdlib / Modules / Objects / VM and record gopy target + upstream change summary.
• File a tracking task per pending row above (one task per row, not one per bucket. Each row maps to a discrete port refresh).
• Land the seven "Highlights" patches before the next release.
• Flip remaining pending rows as their refreshes land.
• Open 1707_3146.md when v3.14.6 ships.