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Unchecked pin construction is accepted without an immovability proof obligation · case 04

Unchecked pin construction is accepted without an immovability proof obligation.

Member previewVariant 4 · 3 implementations · 21 checks per implementation

Case contract

Check a toy pin-aware ownership IR. Pinned non-Unpin values may not move; field projection requires structural pin declaration; unpinned fields remain movable; replace through pinned reference requires Unpin; pinned destructor cannot move receiver; packing disallows safe pinned field references; projecting through shared pointer cannot produce unique pinned reference; converting pin to raw keeps provenance; unchecked pin construction requires an explicit immovability proof; frame relocation invalidates an earlier pin proof. Input is a fully explicit descriptor of the stated toy IR. Return rule identifiers in declaration order; absent optional obligations use the provided neutral defaults. No rule is an assertion about a production language.

Why this case matters

A finite offline static-analysis model of ownership and borrowing; it does not execute the analyzed program.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
unchecked-pin-proof regression 0	`[]`	`["unchecked-pin-proof"]`	Failed

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