build: Produce statically-linked images with musl (#440)

.github/workflows/release.yml

@@ -58,16 +58,10 @@ jobs:
       PACKAGE_VERSION: ${{ needs.meta.outputs.version }}
       CARGO_RELEASE: "1"
       DEBIAN_FRONTEND: noninteractive
-    container: docker://ghcr.io/linkerd/dev:v43-rust
+    container: docker://ghcr.io/linkerd/dev:v43-rust-musl
     steps:
       - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
       - run: git config --global --add safe.directory "$PWD" # actions/runner#2033
-      - run: just rustup
-        if: matrix.arch != 'amd64'
-      - run: apt-get update && apt-get install -y g++-aarch64-linux-gnu gcc-aarch64-linux-gnu libc6-dev-arm64-cross
-        if: matrix.arch == 'arm64'
-      - run: apt-get update && apt-get install -y g++-arm-linux-gnueabihf  gcc-arm-linux-gnueabihf libc6-dev-armhf-cross
-        if: matrix.arch == 'arm'
       - run: just release
       - uses: actions/upload-artifact@a8a3f3ad30e3422c9c7b888a15615d19a852ae32
         with:

justfile

@@ -21,11 +21,11 @@ package_arch := env_var_or_default("ARCH", "amd64")
 # If a `package_arch` is specified, then we change the default cargo `--target`
 # to support cross-compilation. Otherwise, we use `rustup` to find the default.
 _cargo_target := if package_arch == "amd64" {
-        "x86_64-unknown-linux-gnu"
+        "x86_64-unknown-linux-musl"
     } else if package_arch == "arm64" {
-        "aarch64-unknown-linux-gnu"
+        "aarch64-unknown-linux-musl"
     } else if package_arch == "arm" {
-        "armv7-unknown-linux-gnueabihf"
+        "armv7-unknown-linux-musleabihf"
     } else {
         `rustup show | sed -n 's/^Default host: \(.*\)/\1/p'`
     }
@@ -149,9 +149,7 @@ test *flags:
 
 # Build linkerd-await
 build:
-    {{ _cargo }} build --frozen --target={{ _cargo_target }} \
-        {{ if build_type == "release" { "--release" } else { "" } }} \
-        {{ _fmt }}
+    just-cargo profile={{ build_type }} target={{ _cargo_target }} build
 
 release: fetch build
     @mkdir -p release