add builds for rust compatible musl toolchains

.github/workflows/musl.yaml

@@ -0,0 +1,35 @@
+---
+name: musl
+on:
+  pull_request:
+    paths:
+      - "musl/**"
+      - .github/workflows/musl.yaml
+  push:
+    tags:
+      - "musl-cross-*"
+
+jobs:
+  toolchains:
+    strategy:
+      matrix:
+        target: [aarch64-linux-musl, arm-linux-musleabihf, x86_64-linux-musl]
+    runs-on: ubuntu-22.04
+    name: ${{ matrix.target }}
+    steps:
+      - name: Checkout source
+        uses: actions/checkout@v2
+
+      - name: Build ${{ matrix.target }}
+        run: make ${{ matrix.target }}
+
+      - name: Upload release
+        if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/')
+        uses: svenstaro/upload-release-action@v1-release
+        with:
+          repo_token: ${{ secrets.GITHUB_TOKEN }}
+          file: "${{ matrix.target }}-cross.tar.gz*"
+          tag: ${{ github.ref }}
+          overwrite: true
+          file_glob: true
+

Makefile

@@ -27,6 +27,18 @@ else
 NO_TTY_ARG :=
 endif
 
+arm-linux-musleabihf:
+	docker build --tag 'rust-musl-cross' musl
+	docker run --rm -v $(CURDIR):/mnt/workspace -w /mnt/workspace rust-musl-cross musl/build.sh arm-linux-musleabihf
+
+aarch64-linux-musl:
+	docker build --tag 'rust-musl-cross' musl
+	docker run --rm -v $(CURDIR):/mnt/workspace -w /mnt/workspace rust-musl-cross musl/build.sh aarch64-linux-musl
+
+x86_64-linux-musl:
+	docker build --tag 'rust-musl-cross' musl
+	docker run --rm -v $(CURDIR):/mnt/workspace -w /mnt/workspace rust-musl-cross musl/build.sh x86_64-linux-musl
+
 base: check-base
 	$(CURDIR)/base.bash $(NO_TTY_ARG)
 

musl/Dockerfile

@@ -0,0 +1,14 @@
+FROM debian:buster-slim
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update && \
+    apt-get install -y \
+    build-essential \
+    curl \
+    file \
+    git \
+    sudo \
+    unzip
+
+CMD ["bash"]

musl/build.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+set -ex
+
+if [ $# -ne 1 ]; then
+    echo "usage: $0 target" 2>&1
+    exit 1
+fi
+
+target=$1
+
+git clone --depth 1 https://github.com/richfelker/musl-cross-make.git /tmp/musl
+cp musl/config.mak /tmp/musl
+export CFLAGS="-fPIC -g1 $CFLAGS"
+export TARGET=$target
+make -C /tmp/musl -j4
+make -C /tmp/musl install
+tar -C /tmp/musl -czf ${target}-cross.tar.gz output/
+sha256sum ${target}-cross.tar.gz > ${target}-cross.tar.gz.sha256

musl/config.mak

@@ -0,0 +1,60 @@
+# By default, cross compilers are installed to ./output under the top-level
+# musl-cross-make directory and can later be moved wherever you want them.
+# To install directly to a specific location, set it here. Multiple targets
+# can safely be installed in the same location. Some examples:
+
+#OUTPUT = /opt/musl/armhf
+
+# By default, latest supported release versions of musl and the toolchain
+# components are used. You can override those here, but the version selected
+# must be supported (under hashes/ and patches/) to work. For musl, you
+# can use "git-refname" (e.g. git-master) instead of a release. Setting a
+# blank version for gmp, mpc, mpfr and isl will suppress download and
+# in-tree build of these libraries and instead depend on pre-installed
+# libraries when available (isl is optional and not set by default).
+# Setting a blank version for linux will suppress installation of kernel
+# headers, which are not needed unless compiling programs that use them.
+
+# BINUTILS_VER =
+GCC_VER = 11.2.0
+
+# https://github.com/rust-embedded/cross/issues/478
+# https://github.com/rust-lang/libc/issues/1848
+
+MUSL_VER = 1.1.24
+
+# GMP_VER =
+# MPC_VER =
+# MPFR_VER =
+# ISL_VER =
+# LINUX_VER =
+
+# By default source archives are downloaded with wget. curl is also an option.
+
+# DL_CMD = wget -c -O
+DL_CMD = curl -C - -L -o
+
+# Something like the following can be used to produce a static-linked
+# toolchain that's deployable to any system with matching arch, using
+# an existing musl-targeted cross compiler. This only # works if the
+# system you build on can natively (or via binfmt_misc and # qemu) run
+# binaries produced by the existing toolchain (in this example, i486).
+
+# COMMON_CONFIG += CC="i486-linux-musl-gcc -static --static" CXX="i486-linux-musl-g++ -static --static"
+
+# Recommended options for smaller build for deploying binaries:
+
+COMMON_CONFIG += CFLAGS="-g0 -Os -w" CXXFLAGS="-g0 -Os -w" LDFLAGS="-s"
+
+# Recommended options for faster/simpler build:
+
+COMMON_CONFIG += --disable-nls
+GCC_CONFIG += --enable-languages=c,c++
+GCC_CONFIG += --disable-libquadmath --disable-decimal-float
+GCC_CONFIG += --disable-multilib
+
+# You can keep the local build path out of your toolchain binaries and
+# target libraries with the following, but then gdb needs to be told
+# where to look for source files.
+
+COMMON_CONFIG += --with-debug-prefix-map=$(CURDIR)=