goldeneye-pc-port/AGENTS.md

AGENTS.md — GoldenEye 007 PC Port

What this is

• n64decomp/007: WIP decompilation of GoldenEye 007 (N64), byte-matches US/EU/JP ROMs.
• Active work: PC port modelled on the Perfect Dark PC port (same Rare "Indy" engine family).
• Reference docs: docs/internals.md — architecture, GE-specific RSP deltas, phased plan (§1–§10). docs/dev/findings.md — the Dxx finding log (§F + §H). Look up findings via docs/dev/findings-index.csv (label, one-liner, status; regenerate with tools_pc/gen_findings_index.py), then read only the specific ## Dxx entry (multi-pass labels like D202/D176(a) have large sections — grep within the section or read with offset/limit, don't slurp it whole). Never linear-read. docs/porting-notes.md — the recurring N64→PC bug classes (dense; skim the headers, read what's relevant).
• Open work / known issues: docs/ROADMAP.md — the single tracker; add new items there, never start a new backlog/roadmap file.
• Current status: the README "Status" section (docs/dev/LEVEL-STATUS.md is a historical per-level sweep record). Current task + environment: docs/HANDOFF.md (a rolling local working file — may be absent in a fresh clone; fall back to the README "Status" section).
• Dispatching subagents? docs/dev-process.md — task budgets/deadlines, file partitioning, pre-flight, the standard brief template. Every investigation subagent reads docs/porting-notes.md first and appends to it.

Non-negotiables

1. N64 build untouched. Makefile, tools/, rsp/, ld/ belong to the N64 build. Never modify them for the PC port.
2. Game logic is unmodified. The decomp's control flow and behavior are ground truth for 1:1 fidelity — never change them. All N64 hardware dependencies are satisfied by the port/ layer; if a game file seems to need a behavioral change, stop and check the exception below before assuming the fix belongs in port/. Diagnosis is never restricted — only the fix. Trace a bug as deep into src/game state as the evidence leads, and name the exact struct/field/logic responsible, before deciding which of three buckets it falls in (full framing: docs/dev-process.md). Narrow exception (ABI/layout only): the 32→64-bit pointer-width transition forces a small class of mechanical, semantics-preserving edits that cannot be isolated in port/ — any struct-layout or pointer-width-driven misread caused by 32→64-bit widening, whether in a ROM-serialized record (a struct with a 32-bit-pointer field misaligns when read as 64-bit) or a live runtime struct/union (a raw-byte offset alias into a union arm whose true field shifted because an earlier member in the same union widened — the D209/D210/D255 pattern; see docs/porting-notes.md §A1 for the full catalogue and its diagnostic tells). These follow the PD ground-truth pattern (store the embedded address as u32 and cast to a real pointer at the use site; or read the correctly-named/typed field instead of a raw-offset/mistyped alias), change no logic or behavior, and are each documented in docs/dev/findings.md §F/D3x, cross-tagged to §A1 where that pattern applies. A genuine behavioral difference — the decomp's byte-identical code, given verified-correct inputs, still diverging from real N64 behavior — is not covered by this exception and requires the rule-2 sign-off procedure (docs/dev-process.md) before any src/game edit. No other game-code edits are permitted.
3. Region macros mirror the Makefile. CMakeLists.txt REGION_DEFS must match the N64 Makefile's per-region macro set exactly (finding A1). Divergence = silent branch divergence + link failures.
4. src/libultrare/Makefile.libultrare is ground truth for original-vs-Rare libultra files (finding B3). The PC build compiles: libultra/audio, libultrare/audio (drvrNew/env/reverb), libultra/gu, and libultrare/io/vitbl.c only. All other io/ + os/ files are excluded and shimmed in port/src/libultra.c.
5. rsp/graphics/gmain.s is the RSP ground truth — the authoritative reference for which GBI commands GE emits (modified fast3d, 1545 lines). We do not run it on PC; port/fast3d/ replaces it. Use it to validate the software RSP's command decoding and the custom CC/RM modes.

Tree hygiene & release gate

Standing rules for anything that lands in the tracked tree or in a push. These exist because the repo is public, MIT-licensed, forked, and its history is mostly agent-authored.

1. No local machine paths. Tracked files carry no local absolute paths and no usernames. Use the placeholder convention: <repo> = this working directory, <repos> = the local source-repos root, <games> / <videos> = local media roots, <python> = the local CPython install, <temp> = a writable native temp dir (legend at the top of docs/dev/HANDOFF-ARCHIVE.md). Tools must not default to a machine-specific path — take the path as an argument and error if it is missing.
2. No contributor emails in prose. Credit people by name plus the PR/issue that carries the change ("co-authored with X (#123)"), never an inline <email> trailer inside findings text or docs. Commit-trailer emails must be noreply forms, never a contributor's real address.
3. Every vendored third-party component is declared in NOTICE with its license and holder — the "Third-party code vendored into the port layer" and "Vendored build tooling" lists. GPL sources must ship their license text in-tree (tools/gzipsrc/COPYING). MIT covers only our original work; never relicense inherited code and never re-license the repo (forks depend on the MIT LICENSE staying put).
4. Screenshots are game content. A framebuffer capture is a derivative work of Nintendo/MGM art regardless of which engine drew it. Keep repo imagery documentary and small (bug shots, previews — downscaled), and never commit bulk ROM-derived captures: capture output dirs are gitignored (tools_pc/sweep-captures/cap-*/, tools_pc/sweep-captures/**/*.ppm); the only bulk imagery in the tree is tools_pc/golden/*.png, which exists because verify.sh consumes it. Downloads ship no game content at all.
5. Batch, don't spam. Accumulate approved doc/tree fixes across a session into ONE commit; no per-item branches.
6. Release gate. Before pushing a release: the PII scrub and legal/copyright review reports (gitignored, docs/dev/notes/) must be run and clean, and the README Legal section must name every rights holder the game's trademarks implicate. Rewriting pushed history (squash) needs explicit maintainer consent, and any such report states the remote + branch it applies to.

Critical files

File	Role
docs/internals.md	Architecture + RSP deltas + phased plan (§1–§10). Reference, not a linear read.
docs/dev/findings.md	The Dxx finding log (§F/§H); lookups via docs/dev/findings-index.csv.
CMakeLists.txt	PC build (parallel to the N64 Makefile). Source list + REGION_DEFS live here.
port/src/	Shims: libultra.c (OS API; also shims the scheduler's hardware leaf calls and runs the software RSP inline — the game's real src/sched.c is compiled), n64stubs.c (boot/TLB/FPU/rmon), random.c (PRNG ported verbatim from random.s), ucode.c (microcode segment markers), main.c, video.c, …
port/fast3d/	Software RSP (adapted from the PD port). The main Phase 2 work.
rsp/graphics/gmain.s	GE's RSP ucode — ground truth for GBI/CC/RM.
reference/mouse-injector/README.md	Stub only — the vendored GEPD-Edition Mouse Injector source (GPLv2) was removed from the public repo 2026-09-19 (license hygiene: GPL code + prebuilt binary in an MIT project; it was never compiled here). The stub records provenance + how to re-vendor locally (gitignored). The ported mouse-aim model lives in port/src/input.c (D194 lineage); design record: docs/dev/GEPD-INPUT-PLAN.md.
A local Perfect Dark PC port checkout (fgsfdsfgs/perfect_dark)	Standing reference — consult it whenever a work item has a PD analogue (same Rare engine family): port-layer ground truth (port/fast3d/, crash/system/video), plus copy candidates port/src/preprocess/ (N64→PC asset conversion; filemodel.c is the D43 near-analogue) and mixer.c/input.c/fs.c. Port-layer files only; same family ≠ identical format — validate per field. Full audit: docs/internals.md §2.4.

Build

./build-pc.sh ntsc-final   # or pal-final / jpn-final

Needs CMake + SDL2 + zlib + OpenGL, and must run from the MSYS2 MINGW64 shell (see build-pc.sh header and docs/building.md). ROM goes in ./data/ (not distributed); assets must be extracted from it first (docs/building.md).

Windows build environment (three recurring failure modes — diagnose in this order):

1. Cannot create temporary file in C:\Windows\: Permission denied at the link step. The PE toolchain (ninja → cmd → gcc/ld) needs a writable TMP/TEMP; the msys→native env conversion drops it in non-login shells (agent harnesses; the C:/msys64 tree here was built for D:/M/msys64, so its conversion is unreliable). build-pc.sh now self-heals: it probes a native child's TMP (via a file — piped cmd.exe stdout is unreliable under msys console emulation) and, if broken, re-runs cmake+build under PowerShell with TMP/TEMP set natively (the native→native boundary passes env through intact; only msys→native is broken). If you run cmake/ninja by hand from a broken shell: run them from cmd/PowerShell with C:\msys64\mingw64\bin on PATH. Guard revision (2026-09-28): the re-exec writes a self-contained .ps1 to a temp file and runs powershell -File with plain path/word args only (the msys→native argv conversion mangles $-bearing -Command strings; a file write is conversion-free). Inside: PATH is built explicitly (never trust the inherited value); TMP is chosen from writable candidates (%LocalAppData%\Temp first — [System.IO.Path]::GetTempPath() honours the inherited broken TMP, observed as C:\Windows\); every native step self-logs to build-pc/ge007-native-reexec-{diag,cmake,build}.log; a null $LASTEXITCODE ("did not execute") is a distinct failure (exit 2/3) — in PS 5.1 a piped native command errors out non-terminating and never sets it, so an unguarded if ($LASTEXITCODE -ne 0) passes vacuously. In .ps1, -DROMID=$Var is a literal (bare tokens don't expand) — it must be "-DROMID=$Var". Launch powershell plainly — env -i before it breaks the nested cmake launch (verified 2026-09-28). FIXED 2026-09-30 (fix/build-pc-tmp-reexec): the heredoc .ps1 was byte-identical to a hand-extracted copy — not line endings. Three real bugs: (a) the TMP probe's inline cmd //c "... \"path\" ..." never ran (msys re-escapes embedded quotes as \", which cmd rejects), so every build took the re-exec, and it only tested that TMP existed; (b) the .ps1's toolchain dirs were derived from command -v cmake, which in Git Bash/agent shells is a pip cmake (no MSYS2 toolchain) — the hand-run worked because it passed explicit C:\msys64\... paths; (c) /tmp + cygpath disagree when Git Bash and MSYS2 usr/bin are both on PATH, so the .ps1 could be written to one /tmp and powershell pointed at the other (it then exits 0 having done nothing). Now: the MSYS2 mingw64/bin is located and validated (override: GE_MSYS2_ROOT) and prepended to PATH; the probe is a .cmd file that tests TMP writability; all native-facing files live in the build dir with paths from bash's own pwd -W. Verified from an agent Git Bash shell: fresh + incremental builds, both on the direct path and with a forced unwritable TMP (TMP=C:\Windows\) through the re-exec. FIXED 2026-09-30 (fix/build-pc-reexec-noop): the re-exec exited rc=2 with the diag log ending cmake ran LASTEXITCODE=[]. From a shell with MSYS2 usr/bin first on PATH, powershell inherits a stripped ~13-var env with PATHEXT=.CPL and no ComSpec/TMP/TEMP, so & cmake.exe silently launches nothing. The .ps1 now restores PATHEXT and ComSpec. In that shell the re-exec itself is legitimately needed (no TMP), so the probe is correct. Verified: MSYS2-PATH shell, forced TMP=C:\Windows\, and a no-change incremental run all exit 0 with a fresh exe. FIXED 2026-10-04 (fix/build-arch-tag, D515): a FRESH build dir configured through the re-exec cached CMAKE_HOST_SYSTEM_PROCESSOR "" / CMAKE_SYSTEM_PROCESSOR "" (the stripped env also drops PROCESSOR_ARCHITECTURE, which CMake reads for the host processor — same class as PATHEXT/ComSpec), so cmake/TargetArch.cmake produced an empty arch tag: Target arch: (64bit=FALSE), binary named ge007..exe (a correct 64-bit build; only the name was wrong — found during T7, D513). The .ps1 now restores PROCESSOR_ARCHITECTURE from the machine environment (fallback AMD64; SystemRoot/windir likewise) and logs the four vars to the diag log; cmake/TargetArch.cmake falls back to ${CMAKE_C_COMPILER} -dumpmachine when CMAKE_SYSTEM_PROCESSOR is empty and FATAL_ERRORs instead of emitting an untagged binary. Existing build dirs are unaffected (value already cached); a dir configured before the fix picks up x86_64 on its next in-place reconfigure.
2. cannot open output file ge007.x86_64.exe: Permission denied. A running ge007.x86_64.exe locks the output file (Windows rule; you can't relink over a live PE). Check with Get-Process | Where-Object { $_.ProcessName -like '*ge007*' } and close the game before rebuilding. An agent must not kill the user's game process to make a link succeed.
3. cc1.exe: ... libmpfr-6.dll: cannot open shared object file. The calling PATH lacks C:\msys64\mingw64\bin (the gcc driver finds cc1 via its own directory, but the child needs the mingw DLL dir on PATH). In an msys shell: export PATH="/c/msys64/mingw64/bin:/c/msys64/usr/bin:$PATH" before building.

Verification ritual (after any build-affecting change)

1. Undefined symbols. Every symbol referenced by the compiled set (see CMakeLists.txt: SRC_GAME, SRC_ENGINE, SRC_LIBAUDIO, SRC_LIBULTRARE_AUDIO, SRC_LIBULTRARE_DATA, SRC_GU, SRC_PORT*) must be defined exactly once in the compiled set or in port/. Symbols that live in EXCLUDED files (libultra/io/*, libultrare/io/* except vitbl.c, libultra/os/*, libultrare/os/*, sched.c, rmon.c, vi.c, src/*.s) must be provided by port/src/libultra.c, n64stubs.c, random.c, or ucode.c.
2. Duplicates. No symbol defined twice across the compiled set (watch sp_* stacks, rmon*, os* shims, segment markers).
3. Syntax. Every touched file must parse; ./build-pc.sh is the final word.

Run /linkcheck for this sweep. Record new findings in docs/dev/findings.md §F/§H style (next Dxx label after the last used) and add the label to the §F index.

Phase status

Do not keep a status summary here — it goes stale. Open work, known issues and decisions owed: docs/ROADMAP.md (the single tracker). Current release state: the README "Status" section.