FA-43370 / Borrow checking / Member archive

A reborrow projects from a sibling of the authorized parent place · case 05

A reborrow projects from a sibling of the authorized parent place.

Member previewVariant 5 · 3 implementations · 21 checks per implementation

Case contract

Check statically resolved reborrow chains. Every child has declared parent; chains acyclic; child lifetime subset of parent; mutable child requires unique parent permission; parent use cannot overlap child unique-use points; child place must descend from parent place; nested child cannot bypass suspended intermediate parent; sibling unique reborrows may not overlap points; ending a child does not end its ancestors; killing a parent kills all descendants. Descriptor supplies inferred facts and requested proof obligations. 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
place-descent regression 0	`[]`	`["place-descent"]`	Failed

MEMBER ARCHIVE

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