Initial support for rustc_codegen_gcc

Dockerfile

@@ -11,6 +11,7 @@ RUN apt update -y -q && apt upgrade -y -q && apt update -y -q && \
     gcc \
     gcc-multilib \
     git \
+    flex \
     libc6-dev-i386 \
     libc6-dev:i386 \
     linux-libc-dev \

build/build-rustc-cg-gcc.sh

@@ -0,0 +1,189 @@
+#!/bin/bash
+
+## $1 : version, currently rustc_cg_gcc does not have any and only uses master branch.
+## $2 : destination: a directory or S3 path (eg. s3://...)
+
+set -ex
+
+ROOT=$PWD
+VERSION=$1
+
+if [[ "${VERSION}" != "master" ]]; then
+    echo "Only support building master"
+    exit 1
+fi
+
+FULLNAME=rustc-cg-gcc-${VERSION}-$(date +%Y%m%d)
+
+OUTPUT=${ROOT}/${FULLNAME}.tar.xz
+S3OUTPUT=
+if [[ $2 =~ ^s3:// ]]; then
+    S3OUTPUT=$2
+else
+    if [[ -d "${2}" ]]; then
+        OUTPUT=$2/${FULLNAME}.tar.xz
+    else
+        OUTPUT=${2-$OUTPUT}
+    fi
+fi
+
+## From now, no unset variable
+set -u
+
+OUTPUT=$(realpath "${OUTPUT}")
+
+rm -rf  build-rustc-cg-gcc
+mkdir -p build-rustc-cg-gcc
+
+pushd build-rustc-cg-gcc
+PREFIX=$(pwd)/gcc-install
+
+export CARGO_HOME=$PWD/rustup
+export RUSTUP_HOME=$PWD/rustup
+
+export PATH=$RUSTUP_HOME/bin:$PATH
+
+## Download rustc_cg_gcc
+git clone --depth 1 https://github.com/antoyo/rustc_codegen_gcc.git
+
+## Download rustup and install it in a local dir
+## Installs :
+## - minimal profile
+## - the required build-deps from RUSTUP_COMP_BUILD_DEPS (-c *)
+## - version taken from rust-toolchain file
+
+RUSTUP_COMP_BUILD_DEPS=(rust-src rustc-dev llvm-tools-preview)
+
+curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- --profile minimal \
+                                                               -c "$(printf '%s\n' "$(IFS=,; printf '%s' "${RUSTUP_COMP_BUILD_DEPS[*]}")")" \
+                                                               --no-modify-path \
+                                                               -y \
+                                                               --default-toolchain  "$(cat rustc_codegen_gcc/rust-toolchain)"
+
+source  "$PWD/rustup/env"
+
+##
+## Prepare rustc_cg_gcc
+##
+pushd rustc_codegen_gcc
+
+# where the libgccjit.so will be installed
+echo "$PREFIX/lib"  > gcc_path
+
+./build_sysroot/prepare_sysroot_src.sh
+popd
+
+##
+## Build customized GCC with libgccjit
+##
+
+git clone --depth 1 https://github.com/antoyo/gcc.git
+
+GCC_REVISION=$(cd gcc; git ls-remote --heads "${URL}" "refs/heads/${BRANCH}" | cut -f 1)
+
+# clean
+rm -rf gcc-build  gcc-install
+mkdir -p gcc-build gcc-install
+
+echo "Downloading prerequisites"
+pushd gcc
+./contrib/download_prerequisites
+popd
+
+pushd gcc-build
+LANGUAGES=jit,c++
+PKGVERSION="Compiler-Explorer-Build-libgccjit-${GCC_REVISION}"
+
+CONFIG=("--enable-checking=release"
+        "--enable-host-shared"
+        "--build=x86_64-linux-gnu"
+        "--host=x86_64-linux-gnu"
+        "--target=x86_64-linux-gnu"
+        "--disable-bootstrap"
+        "--enable-multiarch"
+        "--with-abi=m64"
+        "--with-multilib-list=m32,m64,mx32"
+        "--enable-multilib"
+        "--enable-clocale=gnu"
+        "--enable-languages=${LANGUAGES}"
+        "--enable-ld=yes"
+        "--enable-gold=yes"
+        "--enable-libstdcxx-debug"
+        "--enable-libstdcxx-time=yes"
+        "--enable-linker-build-id"
+        "--enable-lto"
+        "--enable-plugins"
+        "--enable-threads=posix"
+        "--with-pkgversion=\"${PKGVERSION}\""
+## this is needed for all libs (gmp, mpfr, …) to be PIC so as to not cause issue
+## when they are statically linked in the libgccjit.so
+        "--with-pic")
+
+../gcc/configure --prefix="${PREFIX}" "${CONFIG[@]}"
+
+make -j"$(nproc)"
+make -j"$(nproc)" install-strip
+popd
+
+##
+## Back to rustc_cg_gcc for building
+##
+pushd rustc_codegen_gcc
+./build.sh --release
+popd
+
+##
+## Everything should be correctly build
+##
+
+##
+## Before packaging, remove build deps
+##
+
+for c in "${RUSTUP_COMP_BUILD_DEPS[@]}"
+do
+    rustup component remove "$c"
+done
+
+##
+## Package everything together:
+## - the rustc toolchain from rustup
+## - libgccjit
+## - librustc_codegen_gcc
+## - sysroot
+
+mkdir -p toolroot
+
+# rustc toolchain
+mv rustup/toolchains/*/* toolroot/
+
+# libgccjit
+mv ./gcc-install/lib/libgccjit.so* toolroot/lib
+
+# cg_gcc backend
+mv ./rustc_codegen_gcc/target/release/librustc_codegen_gcc.so toolroot/lib
+
+# sysroot
+mv ./rustc_codegen_gcc/build_sysroot/sysroot toolroot/
+
+##
+## Simple sanity checks:
+## - check for assembly output
+## - check for correct exec output
+
+echo "fn main() -> Result<(), &'static str> { Ok(()) }" > /tmp/test.rs
+./toolroot/bin/rustc -Cpanic=abort -Zcodegen-backend=librustc_codegen_gcc.so  --sysroot toolroot/sysroot --emit asm -o test.s  /tmp/test.rs
+test test.s
+
+./toolroot/bin/rustc -Cpanic=abort -Zcodegen-backend=librustc_codegen_gcc.so --sysroot toolroot/sysroot /tmp/test.rs
+./test
+
+# Don't try to compress the binaries as they don't like it
+pushd toolroot
+
+export XZ_DEFAULTS="-T 0"
+tar Jcf "${OUTPUT}" --transform "s,^./,./${FULLNAME}/," ./
+
+if [[ -n "${S3OUTPUT}" ]]; then
+    s3cmd put --rr "${OUTPUT}" "${S3OUTPUT}"
+fi