(module print_int_no_leak_pin
  (fn main
    (doc "RED-pin fixture for the 2026-05-14 rpe.1 Cat-A heap-Str leak. Under --alloc=rc, the prelude `print` function's body `let s = (app show x) in (do io/print_str s)` allocates a heap-Str via show, then passes it (borrow) to io/print_str. The let-binder `s` is `ret_mode: Own` for `show __Int`, so codegen should emit ailang_rc_dec(s) at let-scope-close. As of commit 301cbc3 the slab leaks: AILANG_RC_STATS=1 reports `allocs=1 frees=0 live=1` for the trivial `(body (app print 42))` program. Expected post-fix: `allocs == frees && live == 0`.")
    (type (fn-type (params) (ret (con Unit)) (effects IO)))
    (params)
    (body (app print 42))))