85 lines
4.6 KiB
Markdown
85 lines
4.6 KiB
Markdown
|
---
|
|||
|
|
kind: finding
|
|||
|
|
date: 2026-07-21
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
# memllib usage inventory — the prerequisite for the §7.5 ownership decision
|
|||
|
|
|
|||
|
|
_Prerequisite named by `../plans/simplification-plan.md` §5: "inventory which memllib surface
|
|||
|
|
(AudioDriver, MEMLNaut board, display/menu, MIDI) is load-bearing" before choosing between a
|
|||
|
|
fork-pin and vendoring. The operator's §7.5 decision is **vendor the parts we use** ("everything
|
|||
|
|
should be self contained in this repo"). This document is the evidence that decision needs, plus one
|
|||
|
|
consequence that was not visible when it was made._
|
|||
|
|
|
|||
|
|
## Method
|
|||
|
|
|
|||
|
|
Not grep. The firmware was built for real (`arduino-cli`, `rp2040:rp2040:solderparty_rp2350_stamp_xl`,
|
|||
|
|
SLPWorkshop variant) and the **linker map** was read: `MEMLNaut-NISPS.ino.map` distinguishes
|
|||
|
|
translation units that merely compiled from those contributing sections to the final image. This is
|
|||
|
|
the same method that would have caught the daisysp finding (S8) mechanically instead of by reading.
|
|||
|
|
|
|||
|
|
## Result: the compile surface is 24 TUs, and all 24 are linked
|
|||
|
|
|
|||
|
|
| subdir | .cpp linked / present | headers | size |
|
|||
|
|
|---|---|---|---|
|
|||
|
|
| `audio/` | 4 / 4 | 12 | 132K |
|
|||
|
|
| `hardware/` | 7 / 7 | 21 | 176K |
|
|||
|
|
| `interface/` | 8 / 8 | 8 | 108K |
|
|||
|
|
| `synth/` | 3 / 3 | 10 | 1.3M |
|
|||
|
|
| `utils/` | 2 / 2 | 9 | 80K |
|
|||
|
|
| **total** | **24 / 24** | **60** | **~1.8M** |
|
|||
|
|
|
|||
|
|
Every translation unit reachable through the sketch-tree symlinks contributes kept sections to the
|
|||
|
|
image — **no discarded-only TU exists**. memllib is therefore *not* a daisysp situation (41 .cpp
|
|||
|
|
compiled, zero consumers). It is genuinely load-bearing.
|
|||
|
|
|
|||
|
|
The library has 30 `.cpp` in total; the 6 not counted above live outside the five symlinked subdirs
|
|||
|
|
(e.g. `examples/`) and are never compiled by the firmware build. Those are the only part safe to
|
|||
|
|
drop outright.
|
|||
|
|
|
|||
|
|
Firmware's direct include surface is just six entry points — `audio/AudioDriver.hpp`,
|
|||
|
|
`hardware/memlnaut/MEMLNaut.hpp`, `hardware/memlnaut/Pins.hpp`,
|
|||
|
|
`hardware/memlnaut/display/{View,SingleSelectView}.hpp`, `interface/MIDIInOut.hpp`, `PicoDefs.hpp`,
|
|||
|
|
`utils/perf.hpp` — but the transitive closure is the whole of those five subdirs.
|
|||
|
|
|
|||
|
|
**Consequence for vendoring: "the load-bearing subset" is ~1.8 MB / 84 files, i.e. essentially all
|
|||
|
|
of memllib minus `examples/`.** There is no small subset to lift. `synth/` alone is 1.3 MB (mostly
|
|||
|
|
`maximilian.cpp`) and all three of its TUs link.
|
|||
|
|
|
|||
|
|
## The consequence that was not visible when §7.5 was decided
|
|||
|
|
|
|||
|
|
`src/memllib` is not a third-party dependency. It is **the lab's shared library**
|
|||
|
|
(`MusicallyEmbodiedML/memllib`), and our fork is:
|
|||
|
|
|
|||
|
|
- **3 commits ahead** — `bf9691c` (swap memlp includes for nisps/core, inline RL utilities),
|
|||
|
|
`32cc831` (newlib RNG fix), `b37fc53` (seed-helper rename). These are the NISPS-specific changes.
|
|||
|
|
- **31 commits behind** — including `770a990 new staticmlp`, `9fcd459 jolts`, `d0d8a72 noise`,
|
|||
|
|
`616b8e7 cc select`, `a8bf255 verb`, `671abbe screen ordering`, `e291192 l r input swap`.
|
|||
|
|
Diffed against the five subdirs we link: **30 files changed, +2034 / −153**.
|
|||
|
|
|
|||
|
|
Vendoring freezes that gap permanently and converts "we are behind the lab" into "we have our own
|
|||
|
|
divergent copy". That may be exactly what is wanted — self-containment is a real goal, and the lab's
|
|||
|
|
`main` is not obviously a branch we track — but it is a fork of a colleague-shared library, not a
|
|||
|
|
snapshot of a vendor drop, and the 31 commits contain work (`staticmlp`, `jolts`) that sounds
|
|||
|
|
directly relevant to this project.
|
|||
|
|
|
|||
|
|
## Options, with what each costs
|
|||
|
|
|
|||
|
|
1. **Vendor as decided.** Copy the five subdirs into the repo, drop the submodule and the symlink
|
|||
|
|
forest, delete `examples/`. Repo grows ~1.8 MB. Self-contained, no submodule init, PlatformIO
|
|||
|
|
gets a plain `lib/` — this materially simplifies the §5 migration. Cost: the 31 upstream commits
|
|||
|
|
become a manual merge, forever.
|
|||
|
|
2. **Vendor, but first rebase our 3 commits onto upstream `main`.** Same end state, except the
|
|||
|
|
snapshot is current rather than 31 commits stale. Costs one merge now (the three commits are
|
|||
|
|
small and mechanical), and it is the only moment when that merge is cheap.
|
|||
|
|
3. **Fork-pin (status quo + Phase 0's fix).** Already works: the pin is reachable, CI is green,
|
|||
|
|
fresh clones build. Not self-contained, and keeps the submodule friction PlatformIO would rather
|
|||
|
|
not have.
|
|||
|
|
|
|||
|
|
**Recommendation: option 2.** The operator's goal (self-contained) is satisfied identically by 1 and
|
|||
|
|
2, but 2 does not silently discard `staticmlp`/`jolts`/`verb`. Doing the rebase after vendoring
|
|||
|
|
means doing it against a copy that no longer has upstream history — i.e. never.
|
|||
|
|
|
|||
|
|
This decision gates the PlatformIO migration (plan §5), which otherwise has to keep the submodule
|
|||
|
|
and its symlink workaround.
|