fix(bench): two CI regressions from the pinning work — macOS toolchain and the submodule guard

CI 抓到的两条,都是我这批改动引入的:

**1. macOS/Windows 的 fixture 请不到编译器。** 我把 `emit_mcpp` 里显式的
`macos = "llvm@22.1.8"` / `windows = "llvm@20.1.7"` 覆盖换成了单个
`default = mcpp_pin(compiler)`,而 `--compiler default` 在非 clang 请求下返回
`gcc@16.1.0` —— macOS 的 registry 里根本没有 gcc 载荷(matrix.json 的 excluded
里正是这么写的),于是 230_bench_harness 在 macOS 上挂在

    error: toolchain 'gcc@16.1.0': package 'xim:gcc@16.1.0' not found

**宿主是这个决策的一部分**。收敛成一个 `resolves_to_clang()`,`mcpp_pin` 和
`payload_cxx` 都读它,这样「告诉 mcpp 用哪个工具链」和「交给其他引擎的驱动」
不可能指向不同的族。

**2. 233 在所有 e2e job 上红。** 新加的「hub/body 必须在钉住的树里存在」断言,
遇到**声明了但没 checkout 的子模块**时报的是「文件不存在」——而只有 bench
workflow 会 checkout 子模块。用 `mcpp.toml` 作为「已初始化」的标记区分两者:
没初始化就大声跳过并点名,不是失败。

同时把 233 加进 bench workflow 的 plan job(它 checkout 子模块)—— 否则这条
断言在 CI 里一次都不会真正执行,而它正是用来抓 `--hub src/xlings.cppm` 那种
「指向几个月前就没了的文件」的。

Author: speak-agent

.github/workflows/bench.yml

@@ -114,7 +114,19 @@ jobs:
       reference_mcpp: ${{ steps.plan.outputs.reference_mcpp }}
       baseline: ${{ steps.plan.outputs.baseline }}
     steps:
+      # submodules, because the guard below checks that every cell's `hub` and
+      # `body` still EXIST in the pinned workload — the assertion that would
+      # have caught `--hub src/xlings.cppm` naming a file that had been gone for
+      # months. This is the only workflow that checks them out, so it is the
+      # only place that assertion can run.
       - uses: actions/checkout@v4
+        with:
+          submodules: true
+
+      - name: Check the matrix against the harness and the pinned workloads
+        shell: bash
+        run: bash tests/e2e/233_bench_matrix.sh
+
       - id: plan
         shell: bash
         run: |

bench/projects/mcpp/.xmake/linux/x86_64/cache/config

@@ -0,0 +1,11 @@
+{
+    recheck = false,
+    options = {
+        builddir = "/home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp/mcpp-2026.8.11.3/build",
+        mode = "release"
+    },
+    mtimes = {
+        ["xmake.lua"] = 1786600374,
+        ["../common/xmake/payload.lua"] = 1786590977
+    }
+}

bench/projects/mcpp/.xmake/linux/x86_64/cache/cxxmodules

@@ -0,0 +1,280 @@
+{
+    ["core.tools.gcc.has_cflags"] = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++_"] = {
+            ["-B"] = true,
+            ["-time"] = true,
+            ["-pie"] = true,
+            ["-print-multi-directory"] = true,
+            ["-print-multi-os-directory"] = true,
+            ["-x"] = true,
+            ["-S"] = true,
+            ["-o"] = true,
+            ["-print-sysroot"] = true,
+            ["--target-help"] = true,
+            ["-c"] = true,
+            ["-no-canonical-prefixes"] = true,
+            ["-pass-exit-codes"] = true,
+            ["-Xlinker"] = true,
+            ["-save-temps"] = true,
+            ["-Xpreprocessor"] = true,
+            ["-E"] = true,
+            ["-print-multi-lib"] = true,
+            ["-pipe"] = true,
+            ["--help"] = true,
+            ["-print-search-dirs"] = true,
+            ["-print-multiarch"] = true,
+            ["-dumpspecs"] = true,
+            ["-print-libgcc-file-name"] = true,
+            ["--version"] = true,
+            ["-dumpversion"] = true,
+            ["-dumpmachine"] = true,
+            ["--param"] = true,
+            ["-print-sysroot-headers-suffix"] = true,
+            ["-v"] = true,
+            ["-Xassembler"] = true,
+            ["-shared"] = true
+        }
+    },
+    find_program_modules_support_gcc_gxx = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"] = "/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"
+    },
+    ["find_program_mcpp-gcc_arch_x86_64_plat_linux_checktoolcxx"] = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"] = "/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"
+    },
+    ["lib.detect.has_flags"] = {
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__ld__-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default -B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-fPIC"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_deps_format"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-MMD -MF"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx__-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-O3"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_deps_output"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-fvisibility-inlines-hidden"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-std=c++23"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_module_only"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-DNDEBUG"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_module_mapper"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_modules"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-D_GLIBCXX_USE_CXX11_ABI=1"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx__-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_-fPIC"] = true,
+        ["linux_x86_64_/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++__cxx_cxxflags_-B/home/speak/.mcpp/registry/data/xpkgs/xim-x-binutils/2.42/bin --sysroot=/home/speak/.mcpp/registry/subos/default_gcc_deps_file"] = true
+    },
+    ["find_program_mcpp-gcc_arch_x86_64_plat_linux_checktoolld"] = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"] = "/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"
+    },
+    find_programver_modules_support_gcc_gxx = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"] = "16.1.0"
+    },
+    ["core.tools.gcc.has_ldflags"] = {
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++_"] = {
+            ["--defsym"] = true,
+            ["--no-warn-search-mismatch"] = true,
+            ["--warn-execstack"] = true,
+            ["-soname"] = true,
+            ["-T"] = true,
+            ["--format"] = true,
+            ["--no-warn-execstack"] = true,
+            ["--ld-generated-unwind-info"] = true,
+            ["--no-export-dynamic"] = true,
+            ["--no-gc-sections"] = true,
+            ["--check-sections"] = true,
+            ["--no-accept-unknown-input-arch"] = true,
+            ["--help"] = true,
+            ["--disable-new-dtags"] = true,
+            ["--eh-frame-hdr"] = true,
+            ["--gc-sections"] = true,
+            ["--sort-common"] = true,
+            ["--warn-unresolved-symbols"] = true,
+            ["--no-warnings"] = true,
+            ["--no-define-common"] = true,
+            ["-Ttext"] = true,
+            ["--relocatable"] = true,
+            ["--unique"] = true,
+            ["--mri-script"] = true,
+            ["--dynamic-list-cpp-typeinfo"] = true,
+            ["--print-map-discarded"] = true,
+            ["-e"] = true,
+            ["--strip-all"] = true,
+            ["--architecture"] = true,
+            ["--no-map-whole-files"] = true,
+            ["--library"] = true,
+            ["-L"] = true,
+            ["--require-defined"] = true,
+            ["-qmagic"] = true,
+            ["--no-undefined"] = true,
+            ["-rpath"] = true,
+            ["--stats"] = true,
+            ["-m"] = true,
+            ["-assert"] = true,
+            ["-V"] = true,
+            ["--warn-alternate-em"] = true,
+            ["--target-help"] = true,
+            ["--gpsize"] = true,
+            ["--no-check-sections"] = true,
+            ["--no-print-map-locals"] = true,
+            ["-EB"] = true,
+            ["-flto"] = true,
+            ["--omagic"] = true,
+            ["-Qy"] = true,
+            ["-G"] = true,
+            ["--error-unresolved-symbols"] = true,
+            ["--default-symver"] = true,
+            ["--no-relax"] = true,
+            ["-plugin-opt"] = true,
+            ["-Tldata-segment"] = true,
+            ["--no-error-rwx-segments"] = true,
+            ["--accept-unknown-input-arch"] = true,
+            ["--allow-multiple-definition"] = true,
+            ["-Tbss"] = true,
+            ["--dynamic-linker"] = true,
+            ["-no-pie"] = true,
+            ["--no-undefined-version"] = true,
+            ["--no-omagic"] = true,
+            ["--version-script"] = true,
+            ["--enable-linker-version"] = true,
+            ["--sort-section"] = true,
+            ["--no-strip-discarded"] = true,
+            ["--start-group"] = true,
+            ["-Bsymbolic"] = true,
+            ["-F"] = true,
+            ["--trace"] = true,
+            ["-dp"] = true,
+            ["--force-group-allocation"] = true,
+            ["--map-whole-files"] = true,
+            ["-nostdlib"] = true,
+            ["--print-map-locals"] = true,
+            ["-Tdata"] = true,
+            ["--warn-once"] = true,
+            ["-A"] = true,
+            ["--dynamic-list-cpp-new"] = true,
+            ["--discard-all"] = true,
+            ["--auxiliary"] = true,
+            ["--no-print-gc-sections"] = true,
+            ["--version-exports-section"] = true,
+            ["-Bgroup"] = true,
+            ["--enable-non-contiguous-regions"] = true,
+            ["--ctf-variables"] = true,
+            ["--demangle"] = true,
+            ["--dynamic-list"] = true,
+            ["--no-dynamic-linker"] = true,
+            ["--section-start"] = true,
+            ["--error-rwx-segments"] = true,
+            ["--default-script"] = true,
+            ["--reduce-memory-overheads"] = true,
+            ["--print-gc-sections"] = true,
+            ["--disable-linker-version"] = true,
+            ["--no-allow-shlib-undefined"] = true,
+            ["--end-group"] = true,
+            ["--remap-inputs"] = true,
+            ["-Map"] = true,
+            ["-I"] = true,
+            ["--warn-textrel"] = true,
+            ["--copy-dt-needed-entries"] = true,
+            ["-z"] = true,
+            ["--enable-non-contiguous-regions-warnings"] = true,
+            ["--dynamic-list-data"] = true,
+            ["--pop-state"] = true,
+            ["-o"] = true,
+            ["--no-ctf-variables"] = true,
+            ["--no-print-map-discarded"] = true,
+            ["--orphan-handling"] = true,
+            ["--as-needed"] = true,
+            ["-Y"] = true,
+            ["--verbose"] = true,
+            ["--discard-none"] = true,
+            ["--nmagic"] = true,
+            ["--gc-keep-exported"] = true,
+            ["--no-eh-frame-hdr"] = true,
+            ["-a"] = true,
+            ["--cref"] = true,
+            ["--print-output-format"] = true,
+            ["--fatal-warnings"] = true,
+            ["-Bno-symbolic"] = true,
+            ["-dT"] = true,
+            ["--script"] = true,
+            ["-init"] = true,
+            ["-Bshareable"] = true,
+            ["--no-fatal-warnings"] = true,
+            ["--just-symbols"] = true,
+            ["-EL"] = true,
+            ["--relax"] = true,
+            ["--export-dynamic-symbol-list"] = true,
+            ["--out-implib"] = true,
+            ["--default-imported-symver"] = true,
+            ["--discard-locals"] = true,
+            ["-rpath-link"] = true,
+            ["-y"] = true,
+            ["-static"] = true,
+            ["--entry"] = true,
+            ["-P"] = true,
+            ["-fini"] = true,
+            ["--split-by-reloc"] = true,
+            ["--filter"] = true,
+            ["--force-exe-suffix"] = true,
+            ["--pic-executable"] = true,
+            ["--no-whole-archive"] = true,
+            ["--whole-archive"] = true,
+            ["--remap-inputs-file"] = true,
+            ["--strip-debug"] = true,
+            ["--emit-relocs"] = true,
+            ["-g"] = true,
+            ["--spare-dynamic-tags"] = true,
+            ["-O"] = true,
+            ["-Ttext-segment"] = true,
+            ["-f"] = true,
+            ["--no-warn-rwx-segments"] = true,
+            ["--no-error-execstack"] = true,
+            ["-l"] = true,
+            ["--library-path"] = true,
+            ["--print-sysroot"] = true,
+            ["--error-handling-script"] = true,
+            ["--ignore-unresolved-symbol"] = true,
+            ["--version"] = true,
+            ["--warn-rwx-segments"] = true,
+            ["--wrap"] = true,
+            ["--dependency-file"] = true,
+            ["--print-memory-usage"] = true,
+            ["--no-copy-dt-needed-entries"] = true,
+            ["--print-map"] = true,
+            ["--trace-symbol"] = true,
+            ["-u"] = true,
+            ["--allow-shlib-undefined"] = true,
+            ["--no-keep-memory"] = true,
+            ["--oformat"] = true,
+            ["-b"] = true,
+            ["--strip-discarded"] = true,
+            ["-plugin"] = true,
+            ["--enable-new-dtags"] = true,
+            ["--warn-execstack-objects"] = true,
+            ["--export-dynamic-symbol"] = true,
+            ["-Bsymbolic-functions"] = true,
+            ["--no-warn-mismatch"] = true,
+            ["--retain-symbols-file"] = true,
+            ["-c"] = true,
+            ["-Ur"] = true,
+            ["-debug"] = true,
+            ["--undefined-version"] = true,
+            ["--warn-common"] = true,
+            ["-Trodata-segment"] = true,
+            ["--disable-multiple-abs-defs"] = true,
+            ["--task-link"] = true,
+            ["--undefined"] = true,
+            ["--warn-multiple-gp"] = true,
+            ["--error-execstack"] = true,
+            ["--export-dynamic"] = true,
+            ["-h"] = true,
+            ["--warn-section-align"] = true,
+            ["--traditional-format"] = true,
+            ["--push-state"] = true,
+            ["--split-by-file"] = true,
+            ["--no-as-needed"] = true,
+            ["-R"] = true,
+            ["--no-ld-generated-unwind-info"] = true,
+            ["--no-demangle"] = true,
+            ["--output"] = true
+        }
+    },
+    find_program = {
+        gcc = "/home/speak/workspace/github/mcpp-community/mcpp/.xlings/subos/_/bin/gcc",
+        ["/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++"] = "/home/speak/.mcpp/registry/data/xpkgs/xim-x-gcc/16.1.0/bin/g++",
+        nim = false
+    }
+}

bench/projects/mcpp/.xmake/linux/x86_64/cache/detect

@@ -0,0 +1,11 @@
+{
+    cmdlines = {
+        "xmake build -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp",
+        "xmake f -y -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp -m release -o /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp/mcpp-2026.8.11.3/build",
+        "xmake build -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp",
+        "xmake f -y -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp -m release -o /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp/mcpp-2026.8.11.3/build",
+        "xmake build -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp",
+        "xmake f -y -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp -m release -o /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp/mcpp-2026.8.11.3/build",
+        "xmake build -P /home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp"
+    }
+}

bench/projects/mcpp/.xmake/linux/x86_64/cache/history

@@ -0,0 +1,16 @@
+{
+    pin_payload = {
+        default = true,
+        __sourceinfo_default = { },
+        __scriptdir = "/home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp",
+        description = "Pin the hermetic mcpp toolchain payload (required for a fair benchmark)",
+        showmenu = true,
+        __sourceinfo_description = {
+            ["Pin the hermetic mcpp toolchain payload (required for a fair benchmark)"] = {
+                line = 76,
+                file = "./xmake.lua"
+            }
+        },
+        __sourceinfo_showmenu = { }
+    }
+}

bench/projects/mcpp/.xmake/linux/x86_64/cache/option

@@ -0,0 +1 @@
+{ }

bench/projects/mcpp/.xmake/linux/x86_64/cache/package

@@ -0,0 +1,3 @@
+{
+    projectdir = "/home/speak/workspace/github/mcpp-community/mcpp/bench/projects/mcpp"
+}