Prove numerical cast plan selection and metadata conversion

[joshlf]

Accepted plans preserve complete rounded sizes for every natural element
count and retain the destination alignment requirement. Prove both selection
paths, then prove the unchecked metadata implementation returns its exact
affine map whenever its product and sum fit. Rejected plans remain conservative.

Extract the actual numerical functions, retain independent arbitrary-outcome
contract checks, and document the restricted external correspondence for
unchecked integer operations. Pointer construction is outside these claims.

Validation: fresh extraction, required proofs and axiom audit; MSRV, stable,
nightly and workspace Clippy checks.

Agent-authored-by: AI agent acting on joshlf's behalf

---

• 　  Prove record construction against independent Rust references #3744
• 　  Prove cast metadata composition against reference sizes #3777
• 👉 Prove numerical cast plan selection and metadata conversion #3776
• 　  Prove cast validation and exact metadata inference #3755
• 　  Prove allocation size preparation and tail containment #3790
• 　  Prove the concrete CastUnsized layout gate #3789
• 　  Prove split lengths and non-overlapping numerical regions #3788
• 　  Prove byte advancement and padding sequence queries #3754
• 　  Prove normalized layout padding and field extension #3753
• 　  Prove concrete pointer metadata operations #3787
• 　  Prove exact trailing sizes, padding and capacity #3752
• 　  Prove primitive layout constructors with recursive mathematical models #3751
• 　  Compare nested DST sizes with a recursive Rust oracle #3749
• 　  Model alignment and phase encoding as a bounded mathematical pair #3747
• 　  Refine recursive record semantics into normalized layouts #3743
• 　  Prove trailing-layout normalization and capacity arithmetic #3742
• 　  Reuse Aeneas specifications for views and indexed loops #3745
• 　  Strengthen arithmetic specifications and prove arithmetic corollaries #3746
• 　  Check native total and partial Aeneas specifications #3739
• 　  Prove unsigned byte-order reads, writes and updates #3800
• 　  Verify doc-owned specifications over recursive mathematical models #3738
• 　  Separate numerical cast planning from typed pointer projection #3774
• 　  Move pointer cast implementation into its own source file #3773
• 　  Share Rust mathematical models across Anneal frontends #3799

Latest Update: v7 — Compare vs v6

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v6		vs v5	vs v4	vs v3	vs v2	vs v1	vs Base
v5			vs v4	vs v3	vs v2	vs v1	vs Base
v4				vs v3	vs v2	vs v1	vs Base
v3					vs v2	vs v1	vs Base
v2						vs v1	vs Base
v1							vs Base

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-05T17:22:02.857588Z	b323a93	PR opened
🔒 Security Review	✅ Completed 2026-10-05T17:23:41.810376Z	b323a93	PR opened

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Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (Gurqevo3e4xhhk2x275sikrq6qmdyzyqb@74f3f4d). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
zerocopy/src/layout/cast_from.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@                         Coverage Diff                          @@
##             Gurqevo3e4xhhk2x275sikrq6qmdyzyqb    #3776   +/-   ##
====================================================================
  Coverage                                     ?   52.17%           
====================================================================
  Files                                        ?       27           
  Lines                                        ?     4393           
  Branches                                     ?        0           
====================================================================
  Hits                                         ?     2292           
  Misses                                       ?     2101           
  Partials                                     ?        0           

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