fix(rust): an array literal where a Vec is declared is a vec!

[gHashTag]

Closes #3349

The headline is the measurement, not the fix. Three emitter repairs in a row measured +0 on the Rust column while demonstrably correcting the emission. The reason is structural and had never been measured.

Real rustc errors per failing spec, over 243:

errors	specs
1	55
2	38
3	19
4	17
5+	114

Median 4. A fix flips a spec to OK only when it closes that spec's last error, so targeting the largest first-error class is the wrong rule — the big classes are spread across specs that each carry several more defects. The right target is the class that is the sole error in one of the 55: expected one of … 7, cannot find type 7, mismatched types 5, expected type, found keyword 5, use of moved value 3.

The count had to be taken twice. grep -cE '^error' also matches error: aborting due to N previous errors, which inflates every bucket by one and turns 55 specs with one error into zero specs with one error — the exact opposite conclusion, and the one I wrote down first.

The fix itself is narrow: var xs : []u32 = []; maps its type to Vec<u32> and emits its value as []. Nine of the twenty mismatched types first-errors are that pair. This closes the local position, the only one of its three with an unambiguous answer; return [] and pub const N: Vec<u32> = [...] are the other two, and a Vec cannot be a constant in Rust at all — that one is a question about the type mapping, not about the line.

Measured, two pinned binaries of distinct hashes: 338 both sides, zero regressions, first error moved on 1 of 14. One predicate, two call sites — gen_fn carries its own copy of the local-emission logic, as #3341 found the hard way.

[github-actions]

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[github-actions]

PR Dashboard

Generated at: 2026-09-06 04:01:30 UTC

• fix(rust): an array literal where a Vec is declared is a vec! #3350 fix(rust): an array literal where a Vec is declared is a vec! | Created: 2026-09-06 | Updated: 2026-09-06 | 19 failing / 29 total
• coq(CorePhi): replace proofs that were never checked by a compiler #3343 coq(CorePhi): replace proofs that were never checked by a compiler | Created: 2026-09-06 | Updated: 2026-09-06 | 5 failing / 32 total
• ci(coq): report all thirteen files instead of stopping at the first error #3342 ci(coq): report all thirteen files instead of stopping at the first error | Created: 2026-09-06 | Updated: 2026-09-06 | 3 failing / 30 total
• skill: spool four lessons from this pass #3327 skill: spool four lessons from this pass | Created: 2026-09-05 | Updated: 2026-09-05 | 1 failing / 28 total
• ci(release): drop a dispatch that can only fail #3325 ci(release): drop a dispatch that can only fail | Created: 2026-09-05 | Updated: 2026-09-05 | 0 failing / 28 total
• ci: zero checks is not zero failures, on the path that merges #3314 ci: zero checks is not zero failures, on the path that merges | Created: 2026-09-05 | Updated: 2026-09-05 | 0 failing / 28 total
• chore(ci)(deps): bump actions/attest-build-provenance from 1 to 4 #3001 chore(ci)(deps): bump actions/attest-build-provenance from 1 to 4 | Created: 2026-09-01 | Updated: 2026-09-05 | 0 failing / 30 total
• chore(ci)(deps): bump softprops/action-gh-release from 2 to 3 #3000 chore(ci)(deps): bump softprops/action-gh-release from 2 to 3 | Created: 2026-09-01 | Updated: 2026-09-05 | 0 failing / 28 total
• chore(ci)(deps): bump github/codeql-action from 3 to 4 #2999 chore(ci)(deps): bump github/codeql-action from 3 to 4 | Created: 2026-09-01 | Updated: 2026-09-05 | 0 failing / 30 total
• Land the formal verification harness on master (it has never run) #2727 Land the formal verification harness on master (it has never run) | Created: 2026-08-27 | Updated: 2026-09-05 | 5 failing / 24 total
• chore(deps)(deps): bump thiserror from 2.0.18 to 2.0.20 #2693 chore(deps)(deps): bump thiserror from 2.0.18 to 2.0.20 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump hyper from 1.10.1 to 1.11.0 #2692 chore(deps)(deps): bump hyper from 1.10.1 to 1.11.0 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 33 total
• chore(deps)(deps): bump base64 from 0.22.1 to 0.23.1 #2691 chore(deps)(deps): bump base64 from 0.22.1 to 0.23.1 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump serde from 1.0.228 to 1.0.229 #2690 chore(deps)(deps): bump serde from 1.0.228 to 1.0.229 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump uuid from 1.23.2 to 1.25.0 #2689 chore(deps)(deps): bump uuid from 1.23.2 to 1.25.0 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• Unbreak FPGA CI and correct two unbacked hardware claims #2081 Unbreak FPGA CI and correct two unbacked hardware claims | Created: 2026-08-11 | Updated: 2026-08-20 | 5 failing / 27 total

Summary

Status	Count
Total Open PRs	16
PRs with Failing Checks	10
PRs with All Checks Green	6
READY	5
FAILING	10
PENDING	0

Seal Status

• ⚠️ STALE -- sha256(compiler.rs)=824bbbc7859f != manifest seal=87e5cbd3ad94.
  The committed NMSE numbers were certified against an older compiler.rs.
  Run scripts/reseal-check.sh locally for the two-step reseal command (advisory; not a merge gate).