# Stage 7 — CPU demos

Verdict on this Mac: **PASS**. Linux: **PENDING**.

`scripts/demo-cpu.sh` prints the oracles in E24.

| Line | Meaning |
| --- | --- |
| `oracle 42` | `add(20, 22)`. Not a speed claim. |
| `copy {:ok, <<1, 2, 3>>, 3}` | three payload bytes copied |
| `borrow {:ok, 32, 1}` | one data pointer, seen twice |
| `filled` | four 0x07 bytes written into the binary OTP allocated |
| `frozen <<4, 9>> token 1` | in-place poke, then a resource binary, same token |
| `retained` | binary copied into an env, then read |
| `dirty_burn_us 49568` | about 50 ms of dirty CPU, including the Elixir call |
| `warm_add_us 4` | one warm `add/1` pair. A single sample, not a distribution. |

Cold compile time is whatever `mix compile` spent on `mojo build` when the fingerprint was stale. This run's demo itself did not recompile Mojo.

Diagnostic path when a call fails: the Elixir stub in `lib/mojoler/`, the wrapper in `native/` or `native/generated/`, the user file in `native/examples/` if it is a DSL entry, then `mojo build --emit llvm` on that file, then `scripts/inspect-abi.sh` for `nm` and `otool` or `ldd`. A trap belongs in `scripts/probe-abort.sh`, not in the test VM. Sanitizers were not run.