test the thumb targets

.cargo/config

@@ -0,0 +1,11 @@
+[target.thumbv6m-none-eabi]
+rustflags = ["-C", "link-arg=-nostartfiles"]
+
+[target.thumbv7m-none-eabi]
+rustflags = ["-C", "link-arg=-nostartfiles"]
+
+[target.thumbv7em-none-eabi]
+rustflags = ["-C", "link-arg=-nostartfiles"]
+
+[target.thumbv7em-none-eabihf]
+rustflags = ["-C", "link-arg=-nostartfiles"]

.travis.yml

@@ -39,6 +39,10 @@ matrix:
     - env: TARGET=powerpc64-unknown-linux-gnu
     - env: TARGET=powerpc64le-unknown-linux-gnu
     - env: TARGET=s390x-unknown-linux-gnu
+    - env: TARGET=thumbv6m-none-eabi
+    - env: TARGET=thumbv7em-none-eabi
+    - env: TARGET=thumbv7em-none-eabihf
+    - env: TARGET=thumbv7m-none-eabi
     - env: TARGET=x86_64-unknown-linux-musl
 
     # just to check these build jobs are skipped during deploys
@@ -54,8 +58,10 @@ install:
   # curl: `std for cross-compilation
   # docker: For transparent QEMU user emulation
   - if [ -z $TRAVIS_TAG ] || [ $TRAVIS_RUST_VERSION = $DEPLOY_VERSION ]; then
-      curl https://static.rust-lang.org/rustup.sh |
-      sh -s -- --add-target=$TARGET --disable-sudo -y --prefix=`rustc --print sysroot`;
+      case $TARGET in thumbv*-none-eabi*) ;; *)
+        curl https://static.rust-lang.org/rustup.sh |
+        sh -s -- --add-target=$TARGET --disable-sudo -y --prefix=`rustc --print sysroot`;;
+      esac;
 
       test $TRAVIS_OS_NAME = osx ||
       docker run --privileged --rm -it ubuntu:16.04 sh -c

Cargo.toml

@@ -7,7 +7,7 @@ version = "0.1.0"
 [build-dependencies]
 gcc = { git = "https://github.com/alexcrichton/gcc-rs" }
 
-[dependencies]
+[target.'cfg(not(target_os = "none"))'.dependencies]
 # Just to test 'cache: cargo'
 clap = "2.13.0"
 

build.rs

@@ -16,4 +16,10 @@ fn main() {
     if env::var_os("CARGO_FEATURE_C").is_some() {
         gcc::compile_library("libhello.a", &["hello.c"]);
     }
+
+    let target = env::var("TARGET").unwrap();
+
+    if target.starts_with("thumb") {
+        println!("cargo:rustc-cfg=thumb");
+    }
 }

ci/docker/thumbv6m-none-eabi/Dockerfile

@@ -0,0 +1,11 @@
+FROM ubuntu:16.04
+RUN apt-get update
+RUN apt-get install -y --no-install-recommends \
+    ca-certificates \
+    curl \
+    gcc \
+    gcc-arm-none-eabi \
+    libc6-dev \
+    libnewlib-dev
+RUN curl -LSfs http://japaric.github.io/trust/install.sh | \
+    sh -s -- --git japaric/xargo --tag v0.2.0 --target x86_64-unknown-linux-gnu --to /usr/bin

ci/docker/thumbv7em-none-eabi/Dockerfile

@@ -0,0 +1,11 @@
+FROM ubuntu:16.04
+RUN apt-get update
+RUN apt-get install -y --no-install-recommends \
+    ca-certificates \
+    curl \
+    gcc \
+    gcc-arm-none-eabi \
+    libc6-dev \
+    libnewlib-dev
+RUN curl -LSfs http://japaric.github.io/trust/install.sh | \
+    sh -s -- --git japaric/xargo --tag v0.2.0 --target x86_64-unknown-linux-gnu --to /usr/bin

ci/docker/thumbv7em-none-eabihf/Dockerfile

@@ -0,0 +1,11 @@
+FROM ubuntu:16.04
+RUN apt-get update
+RUN apt-get install -y --no-install-recommends \
+    ca-certificates \
+    curl \
+    gcc \
+    gcc-arm-none-eabi \
+    libc6-dev \
+    libnewlib-dev
+RUN curl -LSfs http://japaric.github.io/trust/install.sh | \
+    sh -s -- --git japaric/xargo --tag v0.2.0 --target x86_64-unknown-linux-gnu --to /usr/bin

ci/docker/thumbv7m-none-eabi/Dockerfile

@@ -0,0 +1,11 @@
+FROM ubuntu:16.04
+RUN apt-get update
+RUN apt-get install -y --no-install-recommends \
+    ca-certificates \
+    curl \
+    gcc \
+    gcc-arm-none-eabi \
+    libc6-dev \
+    libnewlib-dev
+RUN curl -LSfs http://japaric.github.io/trust/install.sh | \
+    sh -s -- --git japaric/xargo --tag v0.2.0 --target x86_64-unknown-linux-gnu --to /usr/bin

ci/run.sh

@@ -1,10 +1,20 @@
 set -ex
 
 test_mode() {
-    cargo build $flags
-    cargo build $flags --release
+    case $TARGET in
+        thumbv*-none-eabi*)
+            xargo build $flags
+            xargo build $flags --release
+            ;;
+        *)
+            cargo build $flags
+            cargo build $flags --release
+            ;;
+    esac
 
     case $TARGET in
+        thumbv*-none-eabi*)
+            ;;
         s390x-unknown-linux-gnu)
             cargo test $flags --no-run
             cargo test $flags --no-run --release
@@ -19,7 +29,13 @@ test_mode() {
 }
 
 deploy_mode() {
-    cargo rustc $flags --release --bin hello -- -C lto
+    case $TARGET in
+        thumbv*-none-eabi*)
+        ;;
+        *)
+            cargo rustc $flags --release --bin hello -- -C lto
+            ;;
+    esac
 }
 
 run() {

install.sh

@@ -0,0 +1,121 @@
+#!/bin/sh
+
+set -e
+
+say() {
+    echo "install.sh: $1"
+}
+
+say_err() {
+    say "$1" >&2
+}
+
+err() {
+    if [ ! -z $td ]; then
+        rm -rf $td
+    fi
+
+    say_err "ERROR $1"
+    exit 1
+}
+
+need() {
+    if ! command -v $1 > /dev/null 2>&1; then
+        err "need $1 (command not found)"
+    fi
+}
+
+need basename
+need curl
+need cut
+need grep
+need install
+need mkdir
+need mktemp
+need rev
+need rustc
+need tar
+
+force=false
+while test $# -gt 1; do
+    case $1 in
+        --crate)
+            crate=$2
+            shift
+            ;;
+        --git)
+            git=$2
+            shift
+            ;;
+        --force)
+            force=true
+            ;;
+        --tag)
+            tag=$2
+            shift
+            ;;
+        --target)
+            target=$2
+            shift
+            ;;
+        --to)
+            dest=$2
+            shift
+            ;;
+        *)
+            ;;
+    esac
+    shift
+done
+
+if [ -z $git ]; then
+    err 'must specify a git repository using `--git`. Example: `install.sh --git japaric/xargo`'
+fi
+
+url="https://github.com/$git"
+say_err "Git repository: $url"
+
+if [ -z $crate ]; then
+    crate=$(echo $git | cut -d'/' -f2)
+fi
+
+say_err "Crate: $crate"
+
+url="$url/releases"
+
+if [ -z $tag ]; then
+    tag=$(curl -s "$url/latest" | cut -d'"' -f2 | rev | cut -d'/' -f1 | rev)
+    say_err "Tag: latest ($tag)"
+else
+    say_err "Tag: $tag"
+fi
+
+if [ -z $target ]; then
+    target=$(rustc -Vv | grep host | cut -d' ' -f2)
+fi
+
+say_err "Target: $target"
+
+if [ -z $dest ]; then
+    dest="$HOME/.cargo/bin"
+fi
+
+say_err "Installing to: $dest"
+
+url="$url/download/$tag/$crate-$tag-$target.tar.gz"
+
+td=$(mktemp -d || mktemp -d -t tmp)
+curl -sL $url | tar -C $td -xz
+
+for f in $(find $td -type f -executable); do
+    fn=$(basename $f)
+
+    if [ -e "$dest/$fn" ] && [ $force = false ]; then
+        err "$fn already exists in $dest"
+    else
+        mkdir -p $dest
+        install -m 755 $f $dest
+    fi
+done
+
+rm -rf $td

src/bin/hello.rs

@@ -1,8 +1,27 @@
+#![cfg_attr(thumb, feature(lang_items))]
+#![cfg_attr(thumb, no_main)]
+#![cfg_attr(thumb, no_std)]
+
 extern crate trust;
 
+#[cfg(not(thumb))]
 fn main() {
     println!(concat!("target: ",
                      include_str!(concat!(env!("OUT_DIR"), "/target.txt"))));
 
     trust::hello();
 }
+
+#[cfg(thumb)]
+#[no_mangle]
+pub fn _start() -> ! {
+    loop {}
+}
+
+#[cfg(thumb)]
+#[no_mangle]
+pub fn __aeabi_unwind_cpp_pr0() {}
+
+#[cfg(thumb)]
+#[lang = "panic_fmt"]
+fn panic_fmt() {}

src/lib.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(thumb, no_std)]
+
 #[cfg(feature = "c")]
 pub fn hello() {
     extern {