FA-43488 / Borrow checking / Member archive

Call-local loans are released on normal return but retained on unwind · case 03

Call-local loans are released on normal return but retained on unwind.

Member previewVariant 3 · 3 implementations · 21 checks per implementation

Case contract

Validate a callee borrow effect summary against observed static body effects. Reads, writes, moves and escapes are separate effect sets; writes require unique actuals; a returned alias must list every possible argument origin; unknown callees conservatively retain actual references; a noescape assertion excludes body escapes; argument-to-formal mapping must be a bijection over expected formals; normal and unwind exits both release declared call-local loans. 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
unwind-release regression 0	`[]`	`["unwind-release"]`	Failed

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