fix: E0006 Upgrade 提示按安装布局区分 + AUR 特别关照（bump 至 v2026.8.8.4、新增 mcpp-git） (#395)

lildengzi · web-flow · commit 54d29fc859c3 · 2026-08-09T03:42:15.000+08:00
* fix: E0006 Upgrade 提示按安装布局给出指引（AUR 检测 + 推荐默认 xlings），避免误导用户装出第二份（#394） * feat(aur): 新增给 arch 系用户的特别关照 😋（bump mcpp-bin/mcpp-m 至 v2026.8.8.4，消除低于索引下限导致的 E0006；新增 mcpp-git 滚动包，跟随 master 永不滞后）
diff --git a/scripts/aur/README.md b/scripts/aur/README.md
@@ -1,28 +1,31 @@
 # AUR packaging
 
-Arch Linux packaging for mcpp. Two packages, same runtime layout:
+Arch Linux packaging for mcpp. Three packages, same runtime layout:
 
 | Package | What it installs | Pick it when |
 | --- | --- | --- |
 | [`mcpp-bin`](mcpp-bin/) | the **prebuilt** release binary (what [`install.sh`](../../install.sh) downloads) | you just want mcpp, fast |
-| [`mcpp-m`](mcpp-m/) | mcpp **built from source**, bootstrapped with `mcpp-bin` | you want a from-source build |
+| [`mcpp-m`](mcpp-m/) | mcpp **built from source**, bootstrapped with `mcpp-bin` | you want a from-source build of a release |
+| [`mcpp-git`](mcpp-git/) | mcpp **built from the git master**, bootstrapped with `mcpp-bin` | you want to track master (rolling) and never lag the index floor |
 
 ```sh
 yay -S mcpp-bin      # prebuilt
 yay -S mcpp-m        # from source (pulls mcpp-bin as a build dep)
+yay -S mcpp-git      # from git master (pulls mcpp-bin as a build dep)
 ```
 
-The two `conflict` with each other, so only one can be installed at a time.
+The three `conflict` with each other, so only one can be installed at a time.
 Supported architectures: `x86_64`, `aarch64`.
 
 ### Why not just `mcpp`?
 
 The name `mcpp` is already taken by **`extra/mcpp`** — Matsui's C preprocessor,
 an unrelated long-standing official Arch package that owns `/usr/bin/mcpp`. The
 AUR refuses to host any package whose `pkgname` (or `provides`) collides with an
-official-repo package, so our packages are `mcpp-bin` / `mcpp-m`. They still
-install the `mcpp` command at `/usr/bin/mcpp`, so both `conflicts=('mcpp')` with
-that preprocessor — you can have our mcpp or the preprocessor, not both.
+official-repo package, so our packages are `mcpp-bin` / `mcpp-m` / `mcpp-git`.
+They still install the `mcpp` command at `/usr/bin/mcpp`, so all three
+`conflicts=('mcpp')` with that preprocessor — you can have our mcpp or the
+preprocessor, not both.
 
 ## Layout & why the wrapper exists
 
@@ -52,30 +55,39 @@ user already exported, so a custom home or xlings still works.
 First `mcpp build`/`mcpp run` bootstraps the sandbox (downloads ninja, patchelf
 and the default toolchain into `~/.mcpp`) — expected, and only once per user.
 
-### How the `mcpp-m` source package builds
+### How the `mcpp-m` / `mcpp-git` source packages build
 
-mcpp is self-hosting. The `mcpp-m` PKGBUILD uses the installed `mcpp-bin` as the
-bootstrap compiler and runs `mcpp build --target <arch>-linux-musl` — the same
+mcpp is self-hosting. Both source PKGBUILDs use the installed `mcpp-bin` as the
+bootstrap compiler and run `mcpp build --target <arch>-linux-musl` — the same
 path [`release.yml`](../../.github/workflows/release.yml) ships. mcpp downloads
 its own pinned toolchain (it does **not** use the host gcc), so the build needs
 network access, like the upstream release build.
 
+`mcpp-m` builds a pinned release tarball; `mcpp-git` checks out `master` from
+the official repo (`source = mcpp::git+…`, `sha256sums = SKIP`) and derives a
+monotonic `pkgver` from `git describe` (tag + commit distance). Because it
+tracks master, `mcpp-git` can never lag the index floor the way `mcpp-bin` does
+between releases — at the cost of tracking bleeding-edge master.
+
 ## Files
 
 ```
 scripts/aur/
   README.md            this file
-  update.sh            bump BOTH packages to a release version
+  update.sh            bump the release-pinned packages (mcpp-bin, mcpp-m)
   mcpp-bin/{PKGBUILD, .SRCINFO, mcpp.sh}
   mcpp-m/{PKGBUILD, .SRCINFO, mcpp.sh}
+  mcpp-git/{PKGBUILD, .SRCINFO, mcpp.sh}
 ```
 
-`mcpp.sh` is identical in both dirs (each AUR repo must be self-contained);
-`update.sh` keeps them in sync.
+`mcpp.sh` is identical in all three dirs (each AUR repo must be self-contained);
+`update.sh` keeps `mcpp-bin`/`mcpp-m` in sync. `mcpp-git` has no checksums to
+bump (VCS source) and is not touched by `update.sh`.
 
 ## Releasing a new version
 
-After a GitHub release is published (and mirrored), bump both packages:
+After a GitHub release is published (and mirrored), bump the release-pinned
+packages (`mcpp-bin`, `mcpp-m`; `mcpp-git` tracks master and needs no bump):
 
 ```sh
 scripts/aur/update.sh            # uses [package].version from mcpp.toml
diff --git a/scripts/aur/mcpp-bin/.SRCINFO b/scripts/aur/mcpp-bin/.SRCINFO
@@ -1,6 +1,6 @@
 pkgbase = mcpp-bin
 	pkgdesc = Modern C++ build & package management tool (prebuilt binary)
-	pkgver = 0.0.65
+	pkgver = 2026.8.8.4
 	pkgrel = 1
 	url = https://github.com/mcpp-community/mcpp
 	arch = x86_64
@@ -12,9 +12,9 @@ pkgbase = mcpp-bin
 	options = !strip
 	source = mcpp.sh
 	sha256sums = SKIP
-	source_x86_64 = mcpp-0.0.65-linux-x86_64.tar.gz::https://github.com/mcpp-community/mcpp/releases/download/v0.0.65/mcpp-0.0.65-linux-x86_64.tar.gz
-	sha256sums_x86_64 = 0d1d16aae05e4d7c59a00a2621abc4b99421b9821d2145c139fabf95fcf93409
-	source_aarch64 = mcpp-0.0.65-linux-aarch64.tar.gz::https://github.com/mcpp-community/mcpp/releases/download/v0.0.65/mcpp-0.0.65-linux-aarch64.tar.gz
-	sha256sums_aarch64 = 20dd7a8be657bf2e32dcffcf10b758e34fe740fcdb1ceb374822d5ee25cb4a52
+	source_x86_64 = mcpp-2026.8.8.4-linux-x86_64.tar.gz::https://github.com/mcpp-community/mcpp/releases/download/v2026.8.8.4/mcpp-2026.8.8.4-linux-x86_64.tar.gz
+	sha256sums_x86_64 = a8f30fc73fae75381cdd734d204e6c04a24c55365cdf8bb6da07c3aa663c8f9f
+	source_aarch64 = mcpp-2026.8.8.4-linux-aarch64.tar.gz::https://github.com/mcpp-community/mcpp/releases/download/v2026.8.8.4/mcpp-2026.8.8.4-linux-aarch64.tar.gz
+	sha256sums_aarch64 = e0d63de0f6e0111f47df00e9135baf437aed2bcdb883dbb658880d9ee4418e27
 
 pkgname = mcpp-bin
diff --git a/scripts/aur/mcpp-bin/PKGBUILD b/scripts/aur/mcpp-bin/PKGBUILD
@@ -5,7 +5,7 @@
 # how this is published to the AUR and how to bump it (scripts/aur/update.sh).
 
 pkgname=mcpp-bin
-pkgver=0.0.65
+pkgver=2026.8.8.4
 pkgrel=1
 pkgdesc="Modern C++ build & package management tool (prebuilt binary)"
 arch=('x86_64' 'aarch64')
@@ -28,8 +28,8 @@ source_aarch64=("mcpp-${pkgver}-linux-aarch64.tar.gz::${_relbase}/mcpp-${pkgver}
 source=("mcpp.sh")
 
 sha256sums=('SKIP')
-sha256sums_x86_64=('0d1d16aae05e4d7c59a00a2621abc4b99421b9821d2145c139fabf95fcf93409')
-sha256sums_aarch64=('20dd7a8be657bf2e32dcffcf10b758e34fe740fcdb1ceb374822d5ee25cb4a52')
+sha256sums_x86_64=('a8f30fc73fae75381cdd734d204e6c04a24c55365cdf8bb6da07c3aa663c8f9f')
+sha256sums_aarch64=('e0d63de0f6e0111f47df00e9135baf437aed2bcdb883dbb658880d9ee4418e27')
 
 package() {
     local _src="${srcdir}/mcpp-${pkgver}-linux-${CARCH}"
diff --git a/scripts/aur/mcpp-git/.SRCINFO b/scripts/aur/mcpp-git/.SRCINFO
@@ -0,0 +1,21 @@
+pkgbase = mcpp-git
+	pkgdesc = Modern C++ build & package management tool (git master)
+	pkgver = 2026.8.8.4
+	pkgrel = 1
+	url = https://github.com/mcpp-community/mcpp
+	arch = x86_64
+	arch = aarch64
+	license = Apache-2.0
+	makedepends = mcpp-bin
+	makedepends = git
+	depends = git
+	conflicts = mcpp-bin
+	conflicts = mcpp-m
+	conflicts = mcpp
+	options = !strip
+	source = mcpp::git+https://github.com/mcpp-community/mcpp.git
+	source = mcpp.sh
+	sha256sums = SKIP
+	sha256sums = SKIP
+
+pkgname = mcpp-git
diff --git a/scripts/aur/mcpp-git/PKGBUILD b/scripts/aur/mcpp-git/PKGBUILD
@@ -0,0 +1,96 @@
+# Maintainer: mcpp-community <x.d2learn.org@gmail.com>
+#
+# mcpp-git — mcpp built from the upstream git repository (rolling master),
+# bootstrapped with the prebuilt `mcpp-bin`. Same self-hosted build as
+# `mcpp-m`, but tracks master instead of a pinned release — so it can never
+# lag the index floor (E0006) the way `mcpp-bin` does between releases.
+#
+# Rolling master is bleeding-edge: prefer `mcpp-bin` for stable use.
+#
+# NB: the AUR/official name `mcpp` is taken by Matsui's C preprocessor
+# (extra/mcpp), so this package is `mcpp-git`. It still installs the `mcpp`
+# command at /usr/bin/mcpp, hence the conflict with that preprocessor.
+# See scripts/aur/README.md.
+
+pkgname=mcpp-git
+# Static seed only — real builds override it via pkgver() below. Kept at the
+# current release so the AUR listing doesn't look ancient; actual version is
+# whatever master reports at build time.
+pkgver=2026.8.8.4
+pkgrel=1
+pkgdesc="Modern C++ build & package management tool (git master)"
+arch=('x86_64' 'aarch64')
+url="https://github.com/mcpp-community/mcpp"
+license=('Apache-2.0')
+# mcpp/xlings are statically linked; git is used for package-index sync.
+depends=('git')
+# mcpp-bin is the bootstrap compiler; it also supplies the bundled xlings we
+# ship at runtime. git is needed for toolchain/index sync during the build.
+makedepends=('mcpp-bin' 'git')
+# mcpp-bin / mcpp-m = the same tool (mutually exclusive); mcpp = the C
+# preprocessor that also owns /usr/bin/mcpp.
+conflicts=('mcpp-bin' 'mcpp-m' 'mcpp')
+# We strip the built ELF ourselves; don't let makepkg re-strip the vendored
+# xlings binary (a prebuilt third-party artifact).
+options=('!strip')
+
+source=("mcpp::git+https://github.com/mcpp-community/mcpp.git"
+        "mcpp.sh")
+sha256sums=('SKIP'
+            'SKIP')
+
+# Rolling master has no stable release number. Pacman only needs a
+# monotonically increasing pkgver, so derive one from the closest tag plus the
+# commit distance (AUR -git convention): v2026.8.8.4-5-g<hash> →
+# 2026.8.8.4.5.g<hash>. The binary's own version comes from the checked-out
+# source (src/version.cppm), independent of pkgver.
+pkgver() {
+    cd "${srcdir}/mcpp"
+    git describe --long --tags | sed 's/^v//; s/-/./g'
+}
+
+# mcpp downloads its own pinned toolchain (gcc/ninja/patchelf) into the build
+# sandbox — it does not use the host gcc. This needs network access at build
+# time, like the upstream release build.
+build() {
+    cd "${srcdir}/mcpp"
+
+    case "$CARCH" in
+        x86_64)  _target=x86_64-linux-musl  ;;
+        aarch64) _target=aarch64-linux-musl ;;
+        *) echo "unsupported CARCH: $CARCH" >&2; return 1 ;;
+    esac
+
+    # Bootstrap with mcpp-bin's real binary (not its /usr/bin wrapper, which
+    # would force MCPP_HOME into the user's home). Keep the build sandbox
+    # self-contained under $srcdir and reuse mcpp-bin's bundled xlings.
+    export MCPP_HOME="${srcdir}/.mcpp-home"
+    export MCPP_VENDORED_XLINGS="/opt/mcpp/registry/bin/xlings"
+
+    /opt/mcpp/bin/mcpp build --target "$_target"
+
+    _artifact=$(find "target/${_target}" -type f -name mcpp | head -1)
+    test -n "$_artifact" || { echo "build produced no mcpp binary" >&2; return 1; }
+    file "$_artifact" | grep -q 'statically linked'
+    # Debug info on a static ELF balloons it ~7×; strip with the native tool.
+    strip "$_artifact"
+
+    # Stash artifact + the vendored xlings for package() (which has no /opt
+    # guarantees beyond makedepends being installed).
+    install -Dm755 "$_artifact" "${srcdir}/stage/bin/mcpp"
+    install -Dm755 /opt/mcpp/registry/bin/xlings "${srcdir}/stage/registry/bin/xlings"
+}
+
+package() {
+    # Same /opt + wrapper layout as mcpp-bin / mcpp-m (see scripts/aur/README.md
+    # for why the per-user wrapper exists instead of a /usr/bin symlink).
+    install -Dm755 "${srcdir}/stage/bin/mcpp"            "${pkgdir}/opt/mcpp/bin/mcpp"
+    install -Dm755 "${srcdir}/stage/registry/bin/xlings" "${pkgdir}/opt/mcpp/registry/bin/xlings"
+
+    install -Dm755 "${srcdir}/mcpp.sh" "${pkgdir}/usr/bin/mcpp"
+
+    install -Dm644 "${srcdir}/mcpp/LICENSE" \
+        "${pkgdir}/usr/share/licenses/${pkgname}/LICENSE"
+    install -Dm644 "${srcdir}/mcpp/README.md" \
+        "${pkgdir}/usr/share/doc/${pkgname}/README.md"
+}
diff --git a/scripts/aur/mcpp-git/mcpp.sh b/scripts/aur/mcpp-git/mcpp.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+# mcpp launcher (Arch / AUR mcpp-bin package).
+#
+# The AUR package installs mcpp's self-contained tree read-only under
+# /opt/mcpp (shared by every user). But mcpp WRITES its registry sandbox,
+# BMI/metadata caches, logs and downloaded toolchains into MCPP_HOME at
+# runtime — that has to be a per-user, writable location, never /opt.
+#
+# mcpp resolves MCPP_HOME from the binary's real path (/proc/self/exe, which
+# resolves symlinks), so a plain /usr/bin symlink would make MCPP_HOME land in
+# the root-owned /opt tree and every command would fail to write. This wrapper
+# fixes that by pinning the two env knobs the binary honors:
+#
+#   MCPP_HOME            — per-user home (default ~/.mcpp, same as install.sh)
+#   MCPP_VENDORED_XLINGS — the bundled xlings under /opt, which mcpp copies
+#                          into $MCPP_HOME/registry/bin/xlings on first run
+#
+# Both respect a value the user already exported, so power users can still
+# point mcpp at a custom home or xlings.
+set -eu
+
+MCPP_OPT="/opt/mcpp"
+
+export MCPP_HOME="${MCPP_HOME:-$HOME/.mcpp}"
+export MCPP_VENDORED_XLINGS="${MCPP_VENDORED_XLINGS:-$MCPP_OPT/registry/bin/xlings}"
+
+exec "$MCPP_OPT/bin/mcpp" "$@"
diff --git a/scripts/aur/mcpp-m/.SRCINFO b/scripts/aur/mcpp-m/.SRCINFO
@@ -1,6 +1,6 @@
 pkgbase = mcpp-m
 	pkgdesc = Modern C++ build & package management tool (built from source)
-	pkgver = 0.0.65
+	pkgver = 2026.8.8.4
 	pkgrel = 1
 	url = https://github.com/mcpp-community/mcpp
 	arch = x86_64
@@ -12,7 +12,7 @@ pkgbase = mcpp-m
 	conflicts = mcpp-bin
 	conflicts = mcpp
 	options = !strip
-	source = mcpp-0.0.65.tar.gz::https://github.com/mcpp-community/mcpp/archive/v0.0.65.tar.gz
+	source = mcpp-2026.8.8.4.tar.gz::https://github.com/mcpp-community/mcpp/archive/v2026.8.8.4.tar.gz
 	source = mcpp.sh
 	sha256sums = 07f8233d3f18565c52607816a82c9facda3a7ed11c67d3772e42bd84cb54476a
 	sha256sums = SKIP
diff --git a/scripts/aur/mcpp-m/PKGBUILD b/scripts/aur/mcpp-m/PKGBUILD
@@ -11,7 +11,7 @@
 # See scripts/aur/README.md.
 
 pkgname=mcpp-m
-pkgver=0.0.65
+pkgver=2026.8.8.4
 pkgrel=1
 pkgdesc="Modern C++ build & package management tool (built from source)"
 arch=('x86_64' 'aarch64')
diff --git a/src/pm/index_contract.cppm b/src/pm/index_contract.cppm
diff --git a/tests/unit/test_index_contract.cpp b/tests/unit/test_index_contract.cpp
