docs(plan): the second round's rows, and the two items the first document had left open

The heterogeneous-build plan gains the rows for this round: the declared
payload set and the candidate walk in the two runtime adapters, the fast
path comparing every declared build-program input, the diagnostic for a
version conflict on a package with no C++ module, and the first member of
the tools half of mcpp:plugins.

The multi-device document's section 12.4 listed pocl/lavapipe and the
rule package in the index as not done. Both are done, and neither took
more hours: conda-forge publishes Linux binaries for the two drivers, so
the work was repacking and closure verification rather than building
mesa, and the rules moved to their own repository and are published as
one package whose members features select.

Author: speak-agent

.agents/docs/2026-09-05-heterogeneous-build-ecosystem-design-v2.md

@@ -332,7 +332,8 @@ Status is one of `done`, `open`, `deferred (reason)`.
 | I3 | `compat.opencl-headers`, `compat.opencl` verified with a probe (`tests/examples/opencl`, a workspace member); `compat.opencl-runtime` 2026.09.05 farms the libraries the host manifests name, their closure and the vendor family, prefers payloads, records the surface; payload entries of `OCL_ICD_FILENAMES` are left to the payload | the probe enumerates the NVIDIA platform on this machine and zero platforms on a runner; the pocl platform once X2 is installed | X2 for the pocl half | done for the host half: `tests/examples/opencl` lists `NVIDIA CUDA / RTX 4080` here and zero platforms on the Linux runner; with `OCL_ICD_FILENAMES=<pocl>/lib/libpocl.so` the same loader lists `Portable Computing Language` and `NVIDIA CUDA` in one process |
 | I4 | CI green; merge; index artifact published | `Publish Index Artifact` green on the merge commit | I1–I3 | done: PR #349 green (10 pass; the `full sweep` job skips by design), merged as 754d775, `Publish Index Artifact` green on it (run 33968256961) |
 
-| I5 | `compat.vulkan-runtime` 2026.09.06: the payload set is declared as `xpm.linux.deps.runtime` rather than discovered in the store; `PAYLOAD_PACKAGES` maps each soname to the package declared for it and reports a declaration that did not take effect; both adapters refuse a payload built for another machine (ELF `e_machine`); the Vulkan adapter gains the aarch64 multiarch directories | a fresh environment substitutes the same set a developer machine does; the report contains no line saying a declaration did not take effect | I4, X5 | see section 6.4 |
+| I5 | `compat.vulkan-runtime` 2026.09.06: the payload set is declared as `xpm.linux.deps.runtime` rather than discovered in the store; `PAYLOAD_PACKAGES` maps each soname to the package declared for it and reports a declaration that did not take effect; both adapters refuse a payload built for another machine (ELF `e_machine`); the Vulkan adapter gains the aarch64 multiarch directories | a fresh environment substitutes the same set a developer machine does; the report contains no line saying a declaration did not take effect | I4, X5 | done: merged as 0bbf3ad, index artifact published; measured in a fresh subos, 24 payload substitutions against 1, and four host sonames without a payload against thirty |
+| I6 | Both adapters 2026.09.07: a soname carried by more than one installed payload is decided by symbol coverage rather than by which store path sorts last; `compat.vulkan` and `compat.opencl` move their pins | in a fresh subos, `libX11.so.6` comes from `xim:libX11` rather than staying on the host with `xim:mesa-lavapipe`'s bundled copy named as the reason | I5 | PR #351 |
 
 #### xim-pkgindex (PR #762)
 
@@ -345,6 +346,22 @@ Status is one of `done`, `open`, `deferred (reason)`.
 | X4 | `xim:mesa` gains the Intel Vulkan driver | on an Intel machine `HOST-SURFACE.txt` has no driver entry | libclc and SPIRV-LLVM-Translator payloads | deferred: anv requires `intel_clc`, which needs a libclc and clang chain this index does not publish yet; the chain is a separate packaging round and is recorded here rather than approximated |
 | X5 | CI green; merge; index artifact published | `Publish Index Artifact` green on the merge commit | X1–X3 | done: PR #762 green on its pull_request-event runs (the push-event `linux-install-test` sees only the last push and fails on libbsd by construction, as the workflow header states), merged as 2d2a2ee; `Publish Index Artifact` green on it (run 33967729241) |
 
+#### mcpp, second round (PR #570, version 2026.9.5.4)
+
+| # | task | criterion | depends on | status |
+|---|---|---|---|---|
+| M7 | The fast path compares every declared build-program input, not only glob path sets | e2e 612: editing a file declared with `rerun_if_changed` changes what the binary prints, and an unchanged input still takes the fast path | — | done: verified failing on 2026.9.5.3 and passing on this branch |
+| M8 | A version conflict on a package with no named C++ module names both versions and both requesters | the message example 10 produced now says which two versions are in the graph | — | done |
+| M9 | The markers removed from `bench/`, `tools/`, `scripts/`, `mcpp.toml` and `README.zh-CN.md`; the Chinese target table gains the row and the words its English counterpart has | a sweep over the emoji ranges returns nothing outside program output | — | done |
+| M10 | Release 2026.9.5.4, mirror, index bump, bootstrap pin | both mirrors return 200 and identical bytes; xim-pkgindex names it as `latest` | M7-M9 | open |
+
+#### mcpp-plugins, second round (PR #2, version 0.1.1)
+
+| # | task | criterion | depends on | status |
+|---|---|---|---|---|
+| P4 | `mcpp.tools.embed`, the first member of the tools half, selected by `tools-embed` | the fixture activating only that feature embeds a data file, and its second run proves an edit reaches the binary | M7 | done, CI pending on the 2026.9.5.4 release |
+| P5 | The markers removed from the rule sources; version 0.1.1; release and mirror; index descriptor; the two examples move their pin | the same two URLs return 200 with one sha256 | P4, M10 | open |
+
 #### Verification
 
 | # | task | criterion | depends on | status |

.agents/docs/2026-09-05-multi-device-ecosystem-design.md

@@ -1238,9 +1238,9 @@ GPU 索引包不自己探测宿主(委托 xim sentinel);链宿主 `libcudart` 
 | 项 | 理由 |
 |---|---|
 | T1.2 `llvm-offload` | `dpcpp@7.1.0` 载荷自带全套 offload 工具,需要 RDC 的工程可用它;独立包仍待做 |
-| T1.4 / T1.5(pocl / lavapipe)与 T4.2 | 需要**重打 mesa 载荷**(见 12.1 末行),或新建 pocl 源码构建配方。两者都是多小时的载荷工程 |
+| ~~T1.4 / T1.5(pocl / lavapipe)~~ | **已做**(2026-09-06,见 12.6)。理由被一条更短的路推翻:两者在 conda-forge 上都有现成的 Linux 二进制,重打载荷因此不是「重新构建 mesa」而是「重打包并核验闭包」 |
 | T1.8/T1.9/T1.10(chipstar / adaptivecpp / hip) | 依赖 T1.2/T1.4 |
-| T4.3 规则包进索引 | 依赖 ③ —— 描述符指向 mcpp 的**源码 tarball**(`grpcgen` 同形),tag 不存在则算不出 sha256。规则包已改名到 `mcpplibs` 命名空间,就是为了让它可被引用而不是被复制 |
+| ~~T4.3 规则包进索引~~ | **已做,但形态换了**(2026-09-05/06,见 12.6)。不再指向 mcpp 源码 tarball 的子路径:规则集中到 `mcpp-community/mcpp-plugins`,以一个包 `mcpp:plugins` 发布,成员由 feature 选择。命名空间也随之从 `mcpplibs` 改为 `mcpp` |
 | ⑤ 九个框架 | 依赖 ④ 的规则包条目。`ggml-org.llamacpp` 与 `opencv.opencv` 已在索引里,多后端是改**它们各自的 `-m` 仓库**而不是索引条目。T5.1 已做到「链路全通、卡在载荷矩阵」—— 见 12.5 |
 | T2.6 的端到端判据 | `accel` 已是 `pack::AbiTag` 第四维并进指纹;「`.a` 随包传播」还缺一条跨包的判据 |
 
@@ -1274,3 +1274,25 @@ action **只**挂到可执行/共享库/测试上,而 llama.cpp 的 CUDA 后端
 `cuda_runtime.h` 同一形状,第三次);
 **clang 路线要带 `-D_ALLOW_UNSUPPORTED_LIBCPP`**,因为 NVIDIA 那条 `libc++ is not
 supported` 的守卫看的是 `__CUDACC__`,而 clang 编 CUDA 时自己就定义它。
+
+## 12.6 2026-09-06 补记:12.4 里两行被后一轮关掉
+
+本文 12.4 记的是 2026-09-05 当天的读数。次日那一轮(设计见
+`2026-09-05-heterogeneous-build-ecosystem-design-v2.md` §6)关掉了其中两行,都不是
+靠更多工时,而是靠换一条更短的路。
+
+**T1.4 / T1.5 —— pocl 与 lavapipe 都成了载荷。** 当时写的理由是「需要重打 mesa 载荷
+或新建 pocl 源码构建配方,都是多小时的载荷工程」。这个理由把「载荷」等同于「从源码
+构建」;而 conda-forge 对这两者都发布了 Linux 二进制,于是工作变成重打包并核验闭包。
+`xim:mesa-lavapipe@26.2.1`(x86_64 与 aarch64)与 `xim:pocl@7.1` 已发布,
+`xlings install pocl` 之后 Khronos loader 在一个进程里同时列出
+`Portable Computing Language` 与 `NVIDIA CUDA`。
+
+**T4.3 —— 规则包进了索引,但不是当时设想的形态。** 当时的方案是让描述符指向 mcpp
+源码 tarball 的子路径(`grpcgen` 同形),受阻于「tag 不存在则算不出 sha256」。实际
+落地的是另一种:规则不再住在 mcpp 的 `examples/` 下,而集中到
+`mcpp-community/mcpp-plugins`,以一个包 `mcpp:plugins` 发布,成员由 feature 选择,
+命名空间从 `mcpplibs` 改为 `mcpp`。索引里的 `pkgs/m/mcpp.plugins.lua` 指向那个仓库
+自己的 release 资产,sha256 因此是一个已经存在的文件的哈希。
+
+其余各行的理由未变。