Switch base image to alpine:edge

.github/workflows/build.yml

@@ -2,6 +2,8 @@ name: build
 
 on:
   push:
+    branches:
+      - master
   pull_request:
   workflow_dispatch:
 
@@ -14,25 +16,19 @@ jobs:
       matrix:
         arch:
           - amd64
-          - arm64v8
+          - arm64/v8
     steps:
 
-      - name: install-deps
-        run: |
-          sudo apt update
-          sudo apt install -y \
-            qemu-user-static
+      - name: setup-podman
+        uses: TerrorJack/setup-podman@master
 
       - name: checkout
-        uses: actions/checkout@v3
-
-      - name: patch-dockerfile
-        run: |
-          sed -i 's@rust:alpine@${{ matrix.arch }}/rust:alpine@' Dockerfile
+        uses: actions/checkout@v4
 
       - name: build-image
         run: |
           podman build \
+            --arch ${{ matrix.arch }} \
             --network host \
             --pull \
             --squash-all \
@@ -42,13 +38,14 @@ jobs:
       - name: test-image
         run: |
           podman run \
+            --arch ${{ matrix.arch }} \
             --init \
             --network host \
             --rm \
             --tmpfs /tmp:exec \
             --volume $PWD:/workspace \
             --workdir /workspace \
             rust:alpine-mimalloc \
-            sh -c 'cargo install names && mv $CARGO_HOME/bin/names .'
-          MIMALLOC_VERBOSE=1 ./names
-          file ./names
+            /workspace/test.sh
+          MIMALLOC_VERBOSE=1 ./bin/names
+          file ./bin/names

Dockerfile

@@ -1,4 +1,4 @@
-FROM rust:alpine
+FROM alpine:edge
 
 COPY build.sh mimalloc.diff /tmp/
 

README.md

@@ -1,13 +1,26 @@
 # `rust-alpine-mimalloc`
 
-This Docker image builds upon the official `rust:alpine` image and
-replaces the default musl malloc implementation with
-[`mimalloc`](https://github.com/microsoft/mimalloc). If you build Rust
-or C/C++ static executables in this image, the resulting executables
-will automatically link with `mimalloc` without needing any special
-build flags.
-
-Supported & tested archs: `amd64` and `arm64v8`.
+This Docker image builds upon the `alpine:edge` image, provides
+`cargo`/`rustc` and replaces the default musl malloc implementation
+with [`mimalloc`](https://github.com/microsoft/mimalloc). If you build
+Rust or C/C++ static executables in this image, the resulting
+executables will automatically link with `mimalloc` without needing
+any special build flags.
+
+Notice: we switched away from `rust:alpine` and now uses
+`cargo`/`rust` packaged by alpine. Statically linked executables will
+continue to link against `mimalloc` as intended, but you need extra
+command-line arguments to ensure they are indeed static:
+
+```sh
+$ RUSTFLAGS="-C target-feature=+crt-static" cargo install --target x86_64-alpine-linux-musl foo
+```
+
+The `--target` flag is required. The default target is either
+`x86_64-alpine-linux-musl` or `aarch64-alpine-linux-musl`, and can
+also be extracted from `$(rustc -vV | sed -n "s|host: ||p")`.
+
+Supported & tested archs: `amd64` and `arm64/v8`.
 
 For more details, see this [blog
 post](https://www.tweag.io/blog/2023-08-10-rust-static-link-with-mimalloc).

build.sh

@@ -10,7 +10,9 @@ apk upgrade --no-cache
 
 apk add --no-cache \
   alpine-sdk \
+  cargo \
   cmake \
+  curl \
   mold \
   samurai
 

test.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+set -eu
+
+TARGET=$(rustc -vV | sed -n "s|host: ||p")
+
+RUSTFLAGS="-C target-feature=+crt-static" exec cargo install --root "$PWD" --target "$TARGET" names