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Reference freezing is treated as reversible to exclusive access · case 05

Reference freezing is treated as reversible to exclusive access.

Member previewVariant 5 · 3 implementations · 21 checks per implementation

Case contract

Check reference coercion proof steps. Unique-to-shared freeze is one-way; unsizing preserves owner; trait unsizing retains metadata; array-to-slice length equals array extent; nested mutable references cannot shorten inner lifetime; shared outer references may shorten; deref coercion records every intermediate loan; implicit coercion cannot execute a moving deref; reification of a borrowed function pointer preserves captured lifetimes; never-type branch coercion contributes no invented loan. 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
freeze-direction regression 0	`[]`	`["freeze-direction"]`	Failed

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