ci: Improve build time by caching with sccache

Author: tesuji

.travis.yml

@@ -7,6 +7,13 @@ git:
   depth: false
   quiet: true
 
+cache:
+  directories:
+    - "$HOME/.cargo"
+    - "$HOME/.cache/sccache"
+before_cache:
+  - rm -rf "$HOME/.cargo/registry"
+
 matrix:
   fast_finish: true
   include:

ci/build-run-docker.sh

@@ -1,28 +1,32 @@
 #!/bin/bash
 
 script_dir=$(cd "$(dirname "$0")" && pwd)
-. "$script_dir/shared.sh"
+root_dir="${script_dir}/.."
+
+. "${script_dir}/shared.sh"
 
 set -e
 # Disable cause it makes shared script not to work properly
 #set -x
 
 mkdir -p target
+mkdir -p "${HOME}"/.cargo
+mkdir -p "${HOME}"/.cache/sccache
 
 DOCKER="$1"
 TARGET="$2"
 SKIP_TESTS="$3"
 
 travis_fold start "fetch.image.${TARGET}"
 travis_time_start
-travis_do_cmd sh ci/fetch-rust-docker.sh "$TARGET"
+travis_do_cmd sh ci/fetch-rust-docker.sh "${TARGET}"
 travis_time_finish
 travis_fold end "fetch.image.${TARGET}"
 
 if [ -f "ci/docker/$DOCKER/Dockerfile" ]; then
   travis_fold start "build.Dockerfile.${DOCKER}"
   travis_time_start
-  travis_do_cmd docker build -t "$DOCKER" "ci/docker/$DOCKER/"
+  travis_do_cmd docker build -t "$DOCKER" "ci/docker/${DOCKER}/"
   travis_time_finish
   travis_fold end "build.Dockerfile.${DOCKER}"
 fi
@@ -31,23 +35,28 @@ fi
 docker run \
   --entrypoint sh \
   --user "$(id -u)":"$(id -g)" \
-  --volume "$(rustc --print sysroot)":/travis-rust:ro \
-  --volume "$(pwd)":/src:ro \
-  --volume "$(pwd)"/target:/src/target \
-  --workdir /src \
-  --env TARGET="$TARGET" \
-  --env SKIP_TESTS="$SKIP_TESTS" \
-  --env CARGO_HOME=/src/target/cargo-home \
-  --env CARGO_TARGET_DIR=/src/target \
+  --volume "$(rustc --print sysroot)":/rustc-sysroot:ro \
+  --volume "${root_dir}":/checkout:ro \
+  --volume "${root_dir}"/target:/checkout/target \
+  --workdir /checkout \
+  --env TARGET="${TARGET}" \
+  --env SKIP_TESTS="${SKIP_TESTS}" \
+  --volume "${HOME}/.cargo:/cargo" \
+  --env CARGO_HOME=/cargo \
+  --env CARGO_TARGET_DIR=/checkout/target \
   --env LIBZ_SYS_STATIC=1 \
+  --volume "${HOME}"/.cache/sccache:/sccache \
+  --env SCCACHE_DIR=/sccache \
+  --env RUSTC_WRAPPER=sccache \
   --tty \
   --init \
-  "$DOCKER" \
-  -c 'PATH="$PATH":/travis-rust/bin exec sh ci/run.sh'
+  --rm \
+  "${DOCKER}" \
+  -c 'PATH="${PATH}":/rustc-sysroot/bin sh ci/run.sh'
 
 # check that rustup-init was built with ssl support
 # see https://github.com/rust-lang/rustup.rs/issues/1051
-if ! (nm target/"$TARGET"/release/rustup-init | grep -q Curl_ssl_version); then
+if ! (nm target/"${TARGET}"/release/rustup-init | grep -q Curl_ssl_version); then
   echo "Missing ssl support!!!!" >&2
   exit 1
 fi