Compile toolchains for macOS hosts

Author: simolus3

.github/workflows/prebuild_assets.yml

@@ -14,8 +14,7 @@ jobs:
   compile:
     name: Compile SQLite
     timeout-minutes: 30
-    # We need the intel build because arm runners don't support docker :(
-    runs-on: macos-15-intel
+    runs-on: macos-latest
     outputs:
       artifact_url: ${{ steps.upload.outputs.artifact-url }}
       artifact_id: ${{ steps.upload.outputs.artifact-id }}
@@ -51,20 +50,16 @@ jobs:
       - name: Set up XCode
         if: steps.cache_prebuild.outputs.cache-hit != 'true'
         uses: maxim-lobanov/setup-xcode@v1
-      - name: Setup Docker
-        uses: douglascamata/setup-docker-macos-action@v1
-      - name: Setup Linux build docker image
-        run: docker build -t powersync_kotlin_sqlite3mc_build_helper --load jni
-      - name: Download llvm-mingw
+      - name: Download build tools
         run: |
-          curl -L https://github.com/mstorsjo/llvm-mingw/releases/download/20251118/llvm-mingw-20251118-ucrt-macos-universal.tar.xz -o llvm-ming.tar.xz
-          tar --extract --gzip --file llvm-ming.tar.xz
-          rm llvm-ming.tar.xz
+          cd internal/prebuild-binaries
+          ./download_glibc.sh
+          ./download_llvm_mingw.sh
 
       - name: Compile SQLite with Gradle
         if: steps.cache_prebuild.outputs.cache-hit != 'true'
         run: |
-          ./gradlew --scan -PllvmMingw=$(pwd)/llvm-mingw-20251118-ucrt-macos-universal internal:prebuild-binaries:compileNative
+          ./gradlew --scan internal:prebuild-binaries:compileNative
         shell: bash
       - uses: actions/upload-artifact@v5
         id: upload

internal/prebuild-binaries/build.gradle.kts

@@ -78,10 +78,7 @@ fun compileJni(target: JniTarget): CompiledAsset {
             JniTarget.LINUX_X64, JniTarget.LINUX_ARM -> {}
             JniTarget.WINDOWS_X64, JniTarget.WINDOWS_ARM -> {
                 // For Windows, we compile with LLVM MinGW: https://github.com/mstorsjo/llvm-mingw
-                val path = providers.gradleProperty("llvmMingw")
-                val clang = path.orNull?.let {
-                    Path(path.get()).resolve("bin/clang").toString()
-                } ?: "clang"
+                val clang = layout.buildDirectory.file("llvm-mingw/bin/clang").map { it.asFile.path }
                 clangPath.set(clang)
             }
             JniTarget.MACOS_X64, JniTarget.MACOS_ARM -> {
@@ -154,11 +151,16 @@ val compileNative by tasks.registering(Copy::class) {
     }
 }
 
-val jniCompileTasks: List<CompiledAsset> = JniTarget.entries.map(::compileJni)
+val jniCompileTasks: Map<JniTarget, CompiledAsset> = buildMap {
+    for (target in JniTarget.entries) {
+        put(target, compileJni(target))
+    }
+}
+
 val compileJni by tasks.registering(Copy::class) {
     into(project.layout.buildDirectory.dir("output/jni"))
 
-    for (task in jniCompileTasks) {
+    for (task in jniCompileTasks.values) {
         from(task.output) {
             rename { task.fullName }
         }

internal/prebuild-binaries/download_glibc.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+mkdir -p build/sysroot
+cd build/sysroot
+
+function download_package() {
+  curl -L $1 | tar --extract --gzip
+}
+
+download_package https://archlinux.org/packages/core/x86_64/glibc/download/
+download_package https://archlinux.org/packages/core/x86_64/linux-api-headers/download/
+download_package https://archlinux.org/packages/core/x86_64/gcc/download/
+download_package https://archlinux.org/packages/core/x86_64/gcc-libs/download/
+
+download_package https://archlinux.org/packages/extra/any/aarch64-linux-gnu-glibc/download/
+download_package https://archlinux.org/packages/extra/any/aarch64-linux-gnu-linux-api-headers/download/
+download_package https://archlinux.org/packages/extra/x86_64/aarch64-linux-gnu-gcc/download/

internal/prebuild-binaries/download_llvm_mingw.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+mkdir -p build
+cd build/
+
+curl -L https://github.com/mstorsjo/llvm-mingw/releases/download/20251118/llvm-mingw-20251118-ucrt-macos-universal.tar.xz -o llvm-ming.tar.xz
+tar --extract --gzip --file llvm-ming.tar.xz
+rm llvm-ming.tar.xz
+
+mv llvm-mingw-20251118-ucrt-macos-universal llvm-mingw

plugins/build-plugin/src/main/kotlin/com/powersync/compile/JniLibraryCompile.kt

@@ -87,20 +87,22 @@ abstract class JniLibraryCompile: DefaultTask() {
                 return file.relativeTo(workingDir).path
             }
 
-            if (target == JniTarget.LINUX_X64 || target == JniTarget.LINUX_ARM) {
-                executable = "/opt/homebrew/bin/docker"
-                args(
-                    "run",
-                    "-v", "./jni:/jni",
-                    "-v", "./build:/build",
-                    "powersync_kotlin_sqlite3mc_build_helper",
-                    "clang",
-                    "-fuse-ld=lld"
-                )
-            } else {
-                executable = clang
+            if (target == JniTarget.LINUX_X64) {
+                args("-fuse-ld=lld")
+                args("--sysroot=build/sysroot/")
             }
 
+            if (target == JniTarget.LINUX_ARM) {
+                val gccParent = layout.buildDirectory.dir("sysroot/usr/lib/gcc/aarch64-linux-gnu")
+                val gccPath = filePath(gccParent.get().asFile.listFiles().single())
+
+                args("-fuse-ld=lld")
+                args("--sysroot=build/sysroot/usr/aarch64-linux-gnu/")
+                args("-Wl,-L", gccPath)
+                args("-B", gccPath)
+            }
+
+            executable = clang
             toolchain.orNull?.let { args("-B$toolchain") }
 
             args(