FA-43920 / Borrow checking / Member archive

In-place reallocation preserves references tied to the old allocation epoch · case 05

In-place reallocation preserves references tied to the old allocation epoch.

Member previewVariant 5 · 3 implementations · 21 checks per implementation

Case contract

Check statically tracked reference provenance in a toy allocation IR. An address is not an allocation identity; allocation epoch must match; offset within object or one-past only for nondereferenced pointer; raw-to-reference conversion needs a live origin; integer roundtrip cannot invent provenance; reallocation invalidates old origins; zero-sized allocations still have separate ownership IDs; union reinterpretation needs a declared active variant; stack origins cannot become heap origins by cast; a subobject reference retains the base owner. 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
reallocation-invalidation regression 0	`[]`	`["reallocation-invalidation"]`	Failed

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