chore(bb): refresh pinned Chonk IVC inputs to fix nightly debug build --ci-refresh-chonk

[AztecBot]

What

Refreshes the pinned Chonk IVC inputs (barretenberg/cpp/scripts/chonk-inputs.hash) so the Nightly Debug Build goes green again.

This PR carries the ci-refresh-chonk label and a --ci-refresh-chonk head-commit marker. PR CI's post-action (ci_update_chonk_inputs.sh) regenerates the pinned inputs, uploads the new tarball to S3, verifies the smallest flow through ChonkPinnedIvcInputsTest.AllPinnedFlows, and pushes a follow-up commit replacing the placeholder hash in this PR with the freshly-pinned value. Do not merge until that follow-up commit lands — the hash here is a 0000… placeholder until then.

Supersedes the earlier closed-unmerged refresh attempt #23744; the pin is still at the 2026-05-21 value (209dde8e69a27c9f), so the nightly has stayed red.

Root cause

Nightly debug build run 27085031299 failed in:

FAILED: barretenberg/cpp/scripts/run_test.sh bbapi_tests ChonkPinnedIvcInputsTest.AllPinnedFlows (code: 1)

The failure is on circuit 10/10 (hiding_kernel) of the deploy_ecdsar1+sponsored_fpc pinned flow:

Pub inputs offset mismatch: 669 vs 673
Commitment mismatch: Q_M, Q_C, Q_L, Q_R, Q_O, Q_4, Q_5, Q_ARITH, Q_SORT, ...
C++ exception: Assertion failed: (kernel_return_data_match)
  Reason: kernel_return_data mismatch: proof contains
          { 0x183227397098d014..., 0x0 } but kernel_calldata commitment is { 0x..01, 0x..02 }

The hiding_kernel circuit's public-input layout changed (offset 669 → 673, plus selector-commitment changes), so the precomputed VK and proof baked into the pinned ivc-inputs.msgpack are stale. The reconstructed kernel_return_data from the stale public inputs reads a sentinel {1, 2} (the BN254 generator, i.e. an empty databus column) instead of the real return-data commitment, tripping the consistency check.

That check is BB_ASSERT_DEBUG(kernel_return_data_match, ...) at barretenberg/cpp/src/barretenberg/chonk/chonk.cpp:169 — a debug-only assertion compiled out of release/PR CI. Only the nightly debug build exercises it, which is why the stale pin slips past merge-queue CI.

The pin was last bumped 2026-05-21. Circuit-affecting barretenberg changes have since landed on next without ci-refresh-chonk, most notably:

• fix: harden batch chonk verifier. #23484 fix: harden batch chonk verifier — adds an independent batched-SRS MSM check in IPA::batch_reduce_verify (commitment_schemes/ipa/ipa.hpp); the IPA verifier lives inside the hiding kernel, which accounts for the new public inputs and changed selector commitments.
• feat: optimize sumcheck in ECCVM and Translator #23615 feat: optimize sumcheck in ECCVM and Translator.

Fix

Regenerate and re-pin the Chonk inputs via the standard ci-refresh-chonk flow (this PR). No source changes are needed — the pinned fixtures just need to track the current circuits.

Follow-up (separate)

Because the assertion is debug-only, circuit changes can stale the pin with no PR-CI signal, and refresh PRs have repeatedly been opened and closed without landing. Worth deciding whether chonk_inputs.sh check should exercise the pinned-flow IVC with debug asserts at PR time (or whether the nightly should hard-block), so this is caught before it reaches the nightly. Tracking separately.

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Created by claudebox · group: slackbot

[AztecBot]

Pinned Chonk inputs refreshed to a47acea877d449f2. The update commit includes a head-commit --ci-skip marker so the automatic follow-up run does not repeat CI.

[AztecBot]

Pinned Chonk inputs refreshed to e2dbfa3f4092e24f. The update commit includes a head-commit --ci-skip marker so the automatic follow-up run does not repeat CI.