Cairo VM Heap Allocation Constraint for Linear-Type Memory Safety

The goal is to guarantee that every heap allocation made for a linear‑typed value is reclaimed exactly once when the variable leaves scope, preserving memory safety without a garbage collector.

It is unclear whether the Cairo VM inserts an explicit constraint that ties each allocation instruction to a corresponding drop operation, or whether the prover relies solely on the linear‑type checker to reject traces with leaks or double‑use. This ambiguity may differ between Cairo 0 and Cairo 1.0, where the encoding of allocation and drop has evolved.

Does the Cairo VM generate a specific constraint that couples each heap allocation with a matching drop for linear types? How does the compiler encode the lifetime of a linear variable into the execution trace to prevent leaks or double‑free? Are there version‑specific differences in Cairo 0 versus Cairo 1.0 that alter the heap‑allocation‑drop coupling?