travis: simplify ci scripts

.travis.yml

@@ -42,9 +42,6 @@ matrix:
     - env: TARGET=x86_64-unknown-linux-gnu
       os: linux
 
-before_install:
-  - export PATH="$PATH:$HOME/.cargo/bin"
-
 install:
   - bash ci/install.sh
 

ci/env.sh

@@ -1,60 +1,49 @@
 case $TRAVIS_OS_NAME in
     linux)
-        export HOST=x86_64-unknown-linux-gnu
-        export NM=nm
-        export OBJDUMP=objdump
+        HOST=x86_64-unknown-linux-gnu
+        NM=nm
+        OBJDUMP=objdump
+        LINUX=y
         ;;
     osx)
-        export HOST=x86_64-apple-darwin
-        export NM=gnm
-        export OBJDUMP=gobjdump
+        HOST=x86_64-apple-darwin
+        NM=gnm
+        OBJDUMP=gobjdump
+        OSX=y
         ;;
 esac
 
+# NOTE For rustup
+export PATH="$HOME/.cargo/bin:$PATH"
+
+CARGO=cargo
+RUN_TESTS=y
+
+# NOTE For the host and its 32-bit variants we don't need prefixed tools or QEMU
+if [[ $TARGET != $HOST && ! $TARGET =~ ^i.86- ]]; then
+    GCC_TRIPLE=${TARGET//unknown-/}
+
     case $TARGET in
-    aarch64-unknown-linux-gnu)
-        export PREFIX=aarch64-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/aarch64-linux-gnu
-        ;;
-    arm*-unknown-linux-gnueabi)
-        export PREFIX=arm-linux-gnueabi-
-        export QEMU_LD_PREFIX=/usr/arm-linux-gnueabi
-        ;;
-    arm-unknown-linux-gnueabihf)
-        export PREFIX=arm-linux-gnueabihf-
-        export QEMU_LD_PREFIX=/usr/arm-linux-gnueabihf
-        ;;
         armv7-unknown-linux-gnueabihf)
-        export PREFIX=arm-linux-gnueabihf-
-        export QEMU_LD_PREFIX=/usr/arm-linux-gnueabihf
-        ;;
-    mips-unknown-linux-gnu)
-        export PREFIX=mips-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/mips-linux-gnu
-        ;;
-    mipsel-unknown-linux-gnu)
-        export PREFIX=mipsel-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/mipsel-linux-gnu
-        ;;
-    powerpc-unknown-linux-gnu)
-        export PREFIX=powerpc-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/powerpc-linux-gnu
-        ;;
-    powerpc64-unknown-linux-gnu)
-        export PREFIX=powerpc64-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/powerpc64-linux-gnu
+            GCC_TRIPLE=arm-linux-gnueabihf
             ;;
         powerpc64le-unknown-linux-gnu)
-        export PREFIX=powerpc64le-linux-gnu-
-        export QEMU_LD_PREFIX=/usr/powerpc64le-linux-gnu
-        # QEMU crashes, even running the simplest cross compiled C program:
+            # QEMU crashes even when executing the simplest cross compiled C program:
             # `int main() { return 0; }`
-        export RUN_TESTS=n
+            RUN_TESTS=n
             ;;
         thumbv*-none-eabi)
-        export CARGO=xargo
-        export PREFIX=arm-none-eabi-
+            CARGO=xargo
+            GCC_TRIPLE=arm-none-eabi
             # Bare metal targets. No `std` or `test` crates for these targets.
-        export RUN_TESTS=n
+            RUN_TESTS=n
             ;;
     esac
+
+    if [[ $RUN_TESTS == y ]]; then
+        # NOTE(export) so this can reach the processes that `cargo test` spawns
+        export QEMU_LD_PREFIX=/usr/$GCC_TRIPLE
+    fi
+
+    PREFIX=$GCC_TRIPLE-
+fi

ci/install.sh

@@ -3,7 +3,7 @@ set -ex
 . $(dirname $0)/env.sh
 
 install_qemu() {
-    if [[ $TRAVIS_OS_NAME = "linux" ]]; then
+    if [[ $QEMU_LD_PREFIX ]]; then
         apt-get update
         apt-get install -y --no-install-recommends \
                 binfmt-support qemu-user-static
@@ -15,13 +15,13 @@ install_gist() {
 }
 
 install_binutils() {
-    if [[ $TRAVIS_OS_NAME == "osx" ]]; then
+    if [[ $OSX ]]; then
         brew install binutils
     fi
 }
 
 install_rust() {
-    if [[ $TRAVIS_OS_NAME == "osx" ]]; then
+    if [[ $OSX ]]; then
         curl https://sh.rustup.rs -sSf | sh -s -- -y --default-toolchain=nightly
     else
         rustup default nightly
@@ -33,20 +33,20 @@ install_rust() {
 }
 
 add_rustup_target() {
-    if [[ $TARGET != $HOST && ${CARGO:-cargo} == "cargo" ]]; then
+    if [[ $TARGET != $HOST && $CARGO == cargo ]]; then
         rustup target add $TARGET
     fi
 }
 
 install_xargo() {
-    if [[ $CARGO == "xargo" ]]; then
+    if [[ $CARGO == xargo ]]; then
         curl -sf "https://raw.githubusercontent.com/japaric/rust-everywhere/master/install.sh" | \
             bash -s -- --from japaric/xargo --at /root/.cargo/bin
     fi
 }
 
 main() {
-    if [[ $TRAVIS_OS_NAME == "osx" || ${IN_DOCKER_CONTAINER:-n} == "y" ]]; then
+    if [[ $OSX || ${IN_DOCKER_CONTAINER:-n} == y ]]; then
         install_qemu
         install_gist
         install_binutils

ci/script.sh

@@ -8,8 +8,8 @@ gist_it() {
 }
 
 build() {
-    ${CARGO:-cargo} build --target $TARGET
-    ${CARGO:-cargo} build --target $TARGET --release
+    $CARGO build --tartet $TARGET
+    $CARGO build --target $TARGET --release
 }
 
 inspect() {
@@ -20,7 +20,7 @@ inspect() {
     set -e
 
     # Check presence of weak symbols
-    if [[ $TRAVIS_OS_NAME = "linux" ]]; then
+    if [[ $LINUX ]]; then
         local symbols=( memcmp memcpy memmove memset )
         for symbol in "${symbols[@]}"; do
             $PREFIX$NM target/**/debug/deps/librlibc*.rlib | grep -q "W $symbol"
@@ -34,14 +34,14 @@ run_tests() {
         export RUST_TEST_THREADS=1
     fi
 
-    if [[ ${RUN_TESTS:-y} == "y" ]]; then
+    if [[ $RUN_TESTS == y ]]; then
         cargo test --target $TARGET
         cargo test --target $TARGET --release
     fi
 }
 
 main() {
-    if [[ $TRAVIS_OS_NAME == "linux" && ${IN_DOCKER_CONTAINER:-n} == "n" ]]; then
+    if [[ $LINUX && ${IN_DOCKER_CONTAINER:-n} == n ]]; then
         local tag=2016-08-24
 
         docker run \
@@ -53,9 +53,7 @@ main() {
                -e TRAVIS_OS_NAME=$TRAVIS_OS_NAME \
                -v $(pwd):/mnt \
                japaric/rustc-builtins:$tag \
-               sh -c 'set -ex;
-                      cd /mnt;
-                      export PATH="$PATH:/root/.cargo/bin";
+               sh -c 'cd /mnt;
                       bash ci/install.sh;
                       bash ci/script.sh'
     else