Cross compile for arm

Author: jdetter

.github/workflows/package.yml

@@ -18,7 +18,7 @@ jobs:
           # WARNING - do not upgrade this runner to 24.04 or the self hosted runners because it will break downloads for
           #   anyone who uses a linux distro that doesn't have glibc >= GLIBC_2.38
           - { name: x86_64 Linux, target: x86_64-unknown-linux-gnu, runner: ubuntu-22.04 }
-          - { name: aarch64 Linux, target: aarch64-unknown-linux-gnu, runner: arm-runner }
+          - { name: aarch64 Linux, target: aarch64-unknown-linux-gnu, runner: ubuntu-22.04 }
           # Disabled because musl builds weren't working and we didn't want to investigate. See https://github.com/clockworklabs/SpacetimeDB/pull/2964.
           # - { name: x86_64 Linux musl, target: x86_64-unknown-linux-musl, runner: bare-metal, container: alpine }
           # FIXME: arm musl build. "JavaScript Actions in Alpine containers are only supported on x64 Linux runners"
@@ -42,6 +42,20 @@ jobs:
         if: endsWith(matrix.target, '-musl')
         run: apk add gcc g++ bash curl linux-headers perl git make
 
+      - name: Install aarch64 cross-compilation toolchain
+        if: matrix.target == 'aarch64-unknown-linux-gnu'
+        run: |
+          sudo apt-get update -q
+          sudo apt-get install -y gcc-aarch64-linux-gnu g++-aarch64-linux-gnu
+
+      - name: Set aarch64 cross-compilation env vars
+        if: matrix.target == 'aarch64-unknown-linux-gnu'
+        run: |
+          echo "CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc" >> $GITHUB_ENV
+          echo "CC_aarch64_unknown_linux_gnu=aarch64-linux-gnu-gcc"                  >> $GITHUB_ENV
+          echo "CXX_aarch64_unknown_linux_gnu=aarch64-linux-gnu-g++"                 >> $GITHUB_ENV
+          echo "AR_aarch64_unknown_linux_gnu=aarch64-linux-gnu-ar"                   >> $GITHUB_ENV
+
       - name: Install Rust
         uses: dsherret/rust-toolchain-file@v1
       - name: Set default rust toolchain