docs(ffi-linkage): checkpoint — Phase 6.4+6.5 done; PHASE 6 COMPLETE (library/ #foreign-free); next Phase 7

current/CHECKPOINT-EXTERN-EXPORT.md

@@ -5,7 +5,22 @@ Companion to `current/PLAN-EXTERN-EXPORT.md` — one merged plan: **Part A** add
 every commit, one step at a time per the cadence rule.
 
 ## Last completed step
-**Phase 6.3 — migrate `std/` `#foreign`→`extern`** (`refactor` commit `59f90d2`).
+**Phase 6.5 — migrate `gpu/` `#foreign`→`extern`; `library/` now `#foreign`-free**
+(`refactor` commit `32a7628`). **PHASE 6 COMPLETE.** Final batch: gpu/gles3.sx
+(eglGetProcAddress + 1 comment) + gpu/metal.sx (MTLCreateSystemDefaultDevice), bare
+fn markers → `extern`. Verified byte-identical `sx ir` on importers 1610 (gles3) +
+1606 (metal). **Zero `#foreign` remains anywhere under `library/`** — verified by
+`grep -rln '#foreign' library/` → no matches. Suite green (647 corpus / 444 unit, 0
+failed).
+
+### Prior: Phase 6.4 — migrate `ffi/` `#foreign`→`extern` (`refactor` commit `666a2e2`).
+objc/objc_block/raylib/sdl3/wasm (~51 sites): fn markers + objc.sx's 2 import runtime
+classes (prefix→postfix `extern`). objc + objc_block validated by the 50 marked 13xx
+corpus examples (incl. import classes 1300/1301 + defined classes 1339/1349);
+raylib/ffi-sdl3/wasm verified by byte-identical `sx ir` probes pre/post. Empty snapshot
+diff; suite green.
+
+### Prior: Phase 6.3 — migrate `std/` `#foreign`→`extern` (`refactor` commit `59f90d2`).
 Pure source rename across 11 std modules (~60 sites):
 cli/core/fmt/fs/log/net.kqueue/process/socket/thread/time/trace. All fn-decl markers
 — bare `#foreign;`, `#foreign libc;`/`#foreign tlib;` (LIB ref), and
@@ -194,19 +209,24 @@ AOT), 1227 (export fn rename, AOT), 1348 (objc extern class), 1349 (objc export
 (jni extern class), 1174/1175 (interplay diagnostics).
 
 ## Next step
-**PART B — Phase 6.4 (migrate `library/modules/ffi/` `#foreign`→`extern`/`export`,
-~50 sites).** Phase 6.1 (sqlite) + 6.2 (platform) + 6.3 (std) COMPLETE.
+**PART B — Phase 7 (migrate `examples/` + `issues/` `#foreign`→`extern`/`export`).**
+**PHASE 6 COMPLETE — `library/` is `#foreign`-free.**
 
-- **Phase 6.4** (`refactor`, snapshot diff must be EMPTY): rewrite
-  `library/modules/ffi/` (objc/objc_block/raylib/sdl3/opengl/stb/…) `#foreign`→`extern`.
-  ⚠ Like platform (NOT std), `ffi/objc.sx` has Obj-C **runtime classes** — use the
-  postfix shape (`#objc_class("X") extern {` for imports, `… export {` for defined),
-  and check each site's shape per-file before bulk-replacing. Verify corpus coverage
-  per module: raylib/stb/sdl3 examples (15xx/12xx) compile on host → corpus validates;
-  any host-uncompiled module (check importers) needs an `sx ir` probe like 6.2.
-- **Remaining Phase 6 batches:** 6.5 remaining `library/`+`vendors/` (math/, other
-  vendors, anything still holding `#foreign`). Then **Phase 7** migrates examples +
-  issues the same way.
+- **Phase 7** (`refactor` batches, snapshot diff must be EMPTY per batch): migrate the
+  corpus + issue repros. Batches (PLAN-EXTERN-EXPORT Phase 7): 7.1 `examples/12xx-ffi-*`
+  (plain C), 7.2 `examples/13xx-ffi-objc-*`, 7.3 `examples/14xx-ffi-jni-*`, 7.4
+  `issues/*` repros + stragglers. ⚠ Same shape rules as Phase 6: fn/global markers →
+  `extern …` (blanket keyword swap is safe for fn-only files); runtime classes →
+  postfix (`#objc_class/#jni_class("X") extern {` import, `… export {` defined). Check
+  each file's shapes first. Most examples ARE marker'd → the corpus validates the empty
+  snapshot diff directly; a non-empty diff ⇒ STOP and coalesce, don't regen.
+  - **Decision needed for 7.4:** the `issues/*.md` writeups contain `#foreign` in prose
+    repros — Decision 6 (historical carve-out, STILL OPEN) governs whether those get
+    migrated or kept as provenance. Migrate `issues/*.sx` repros (live tree); defer the
+    `.md` prose pending Decision 6. Also: some examples are diagnostic tests that
+    deliberately reference `#foreign` (e.g. 1174 foreign-postfix-conflict, 1620 lib-ref)
+    — those must KEEP `#foreign` until the Phase 8 cutover (they test the keyword's
+    behavior). Identify and exclude them from the 7.x bulk rename.
 - **6.2 verification note (carry forward):** the `platform/` runtime modules
   (uikit/android/android_jni) are NOT compiled by any marker'd host corpus test — verify
   future platform-adjacent migrations via direct `sx ir` on importers (1610/1606 compile
@@ -333,6 +353,14 @@ Part A ratified (bare / postfix / `⇒ callconv(.c)` / lib-separate). Part B:
   deleted at cutover). Affects only diagnostic wording — IR/behavior identical either way.
 
 ## Log
+- (6.5 gpu) **PHASE 6 COMPLETE.** Migrated `gpu/gles3.sx` + `gpu/metal.sx` (3 sites);
+  `library/` now `#foreign`-free (`grep -rln '#foreign' library/` → 0). Verified
+  byte-identical `sx ir` on importers 1610/1606. Suite green (647/444). `refactor`
+  `32a7628`.
+- (6.4 ffi) Migrated `ffi/` objc/objc_block/raylib/sdl3/wasm (~51 sites): fn markers +
+  objc.sx's 2 import classes (prefix→postfix `extern`). objc/objc_block validated by 50
+  marked 13xx examples; raylib/ffi-sdl3/wasm by `sx ir` probes pre/post. Empty snapshot
+  diff; suite green (647/444). `refactor` `666a2e2`.
 - (6.3 std) Migrated 11 `std/` modules (~60 sites): cli/core/fmt/fs/log/net.kqueue/
   process/socket/thread/time/trace. All fn-decl markers (bare / `libc`|`tlib` LIB ref /
   `libc "csym"` rename) → `extern …` + 2 comment mentions; no class forms. Host-corpus-