Function lanes_simulate_stack 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn lanes_simulate_stack(
    prog: *const LANESProgram,
    out: *mut *mut LANESValidationErrors,
) -> LanesStatus

Stack type simulation (underflow, type mismatches, and lane/location group checks). Runs without an arch spec (duplicate-only group checks) — prefer lanes_simulate_stack_with_arch, which enables the arch-dependent lane-group checks (consistency, bus membership, AOD geometry).