aio-libs / multidict / 37203510052

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Move md_clear() out of line (#1670)

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## What do these changes do?

Marks `md_clear()` `NOINLINE`. It was inlined into
`multidict_tp_dealloc`, `multidict_clear` and `MultiDict_Clear`; now
they call one shared copy. The `md_clear` rule in
`tools/check_inlining.py` forbade exactly this on FT, so it is removed.

The cost is a few instructions per call (callgrind, Ir per op, base vs.
this branch, 3.14.7 and 3.14.7t; rows that moved under 0.2% omitted):

| operation | GIL | FT |
| --- | --- | --- |
| `ctor_empty` (mostly dealloc) | +7 (+1.2% MultiDict, +1.0%
CIMultiDict) | +5 (+0.6%) |
| `copy_small` | +7 (+0.4%) | flat |
| `clear` | +10 (+0.2%) | +12 (+0.2%) |

GIL `.text` shrinks by 756 bytes; FT grows by 136 bytes. The pure-Python
backend is unaffected.

## Are there changes in behavior for the user?

No.

## Is it a substantial burden for the maintainers to support this?

No.

## Related issue number

N/A

## Checklist

- [x] I think the code is well written
- [ ] Unit tests for the changes exist (N/A, no behaviour change;
covered by the existing suite)
- [x] Documentation reflects the changes (N/A)
- [ ] If you provide code modification, please add yourself to
`CONTRIBUTORS.txt` (N/A)
- [x] Add a new news fragment into the `CHANGES/` folder
- [x] `make doc-spelling` passes and any new technical words are added
to `docs/spelling_wordlist.txt`

<details>
<summary>Agent run details (optional, for reviewers)</summary>

Tests: `pytest -q` passed with the C extension on 3.14.7, 3.14.7t and
3.10.17, and on the pure-Python build (`MULTIDICT_NO_EXTENSIONS=1`,
`--no-c-extensions`), each in its own venv.
Inlining: `tools/check_inlining.py` ok on GIL (16 rules) and FT (17
rules).
Benchmarks: `benchmarks/callgrind_driver.py` with `PYTHONHASHSEED=0`,
equal-length tree and venv paths. No pyperf wall-clock run; the change
is a deliberate small regression, and the Ir numbers above show its
size.
</details>

Drafted with Claude... (continued)

792 of 1584 branches covered (50.0%)

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