refactor: use v0.0.16 mcpp to self-host macOS builds (drop xmake)

Since v0.0.16 macOS binary is available, both release and CI can now
self-host: download v0.0.16 → mcpp build → produce new binary.
No xmake needed.

Author: Sunrisepeak

.github/workflows/ci-macos.yml

@@ -268,13 +268,21 @@ jobs:
             *)              echo "FAIL: unexpected platform"; exit 1 ;;
           esac
 
-      - name: Install xmake (for bootstrap)
+      - name: Self-host test (v0.0.16 builds current)
         run: |
-          brew install xmake
-          xmake --version
-
-      - name: Bootstrap mcpp from source (xmake)
-        run: |
-          export LLVM_ROOT="$LLVM_ROOT"
-          bash scripts/bootstrap-macos.sh "$LLVM_ROOT"
-          ./target/bootstrap/bin/mcpp --version
+          # Download v0.0.16 macOS mcpp to bootstrap
+          WORK=$(mktemp -d)
+          curl -fsSL -o "$WORK/mcpp.tar.gz" \
+            "https://github.com/mcpp-community/mcpp/releases/download/v0.0.16/mcpp-0.0.16-macosx-arm64.tar.gz"
+          tar -xzf "$WORK/mcpp.tar.gz" -C "$WORK"
+          BOOTSTRAP="$WORK/mcpp-0.0.16-macosx-arm64/bin/mcpp"
+          test -x "$BOOTSTRAP"
+          "$BOOTSTRAP" --version
+          # Build current source with bootstrap mcpp
+          export PATH="$(dirname "$BOOTSTRAP"):$PATH"
+          mcpp build
+          # Verify the newly built binary
+          SELFHOST=$(find target -path "*/bin/mcpp" | head -1)
+          test -x "$SELFHOST"
+          "$SELFHOST" --version
+          echo ":: Self-host successful!"

.github/workflows/release.yml

@@ -315,47 +315,23 @@ jobs:
           LLVM_ROOT=$(find "$HOME/.xlings" -path "*/xpkgs/xim-x-llvm/*/bin/clang++" | head -1 | xargs dirname | xargs dirname)
           echo "LLVM_ROOT=$LLVM_ROOT" >> "$GITHUB_ENV"
 
-      - name: Install xmake
+      - name: Bootstrap mcpp from v0.0.16 release
         run: |
-          brew install xmake
-          xmake --version
-
-      - name: Build mcpp with xmake + LLVM
+          # Download the v0.0.16 macOS binary to bootstrap this build
+          WORK=$(mktemp -d)
+          curl -fsSL -o "$WORK/mcpp.tar.gz" \
+            "https://github.com/mcpp-community/mcpp/releases/download/v0.0.16/mcpp-0.0.16-macosx-arm64.tar.gz"
+          tar -xzf "$WORK/mcpp.tar.gz" -C "$WORK"
+          BOOTSTRAP="$WORK/mcpp-0.0.16-macosx-arm64/bin/mcpp"
+          test -x "$BOOTSTRAP"
+          "$BOOTSTRAP" --version
+          export PATH="$(dirname "$BOOTSTRAP"):$PATH"
+          echo "PATH=$(dirname "$BOOTSTRAP"):$PATH" >> "$GITHUB_ENV"
+
+      - name: Build mcpp (self-host via v0.0.16)
         run: |
-          # Generate xmake.lua if not present
-          if [ ! -f xmake.lua ]; then
-            cat > xmake.lua << 'EOF'
-          add_rules("mode.release")
-          set_languages("c++23")
-
-          package("cmdline")
-              set_homepage("https://github.com/mcpplibs/cmdline")
-              set_description("Modern C++ command-line parsing library")
-              set_license("Apache-2.0")
-              add_urls("https://github.com/mcpplibs/cmdline/archive/refs/tags/$(version).tar.gz")
-              add_versions("0.0.1", "3fb2f5495c1a144485b3cbb2e43e27059151633460f702af0f3851cbff387ef0")
-              on_install(function (package)
-                  import("package.tools.xmake").install(package)
-              end)
-          package_end()
-
-          add_requires("cmdline 0.0.1")
-
-          target("mcpp")
-              set_kind("binary")
-              add_files("src/main.cpp")
-              add_files("src/**.cppm")
-              add_packages("cmdline")
-              add_includedirs("src/libs/json")
-              set_policy("build.c++.modules", true)
-          EOF
-          fi
-
-          xmake f -y -m release --toolchain=llvm --sdk="$LLVM_ROOT"
-          xmake build -y mcpp
-
-          # Locate and verify built binary
-          MCPP_BIN=$(find build -name mcpp -type f -perm +111 | head -1)
+          mcpp build
+          MCPP_BIN=$(find target -path "*/bin/mcpp" | head -1)
           test -x "$MCPP_BIN"
           file "$MCPP_BIN"
           "$MCPP_BIN" --version