Use rustup to install extra targets

.travis.yml

@@ -1,16 +1,14 @@
 language: rust
 rust:
-  - 1.5.0
+  - stable
   - beta
   - nightly
 sudo: false
 install:
   - if [ "$TRAVIS_OS_NAME" = "linux" ]; then OS=unknown-linux-gnu; else OS=apple-darwin; fi
   - export TARGET=$ARCH-$OS
-  - curl -sO https://static.rust-lang.org/dist/rust-$TRAVIS_RUST_VERSION-$TARGET.tar.gz
-  - tar xf rust-$TRAVIS_RUST_VERSION-$TARGET.tar.gz
-  - rm -rf $HOME/rust/lib/rustlib/$TARGET
-  - mv rust-$TRAVIS_RUST_VERSION-$TARGET/rust-std-$TARGET/lib/rustlib/$TARGET $HOME/rust/lib/rustlib
+  - curl https://static.rust-lang.org/rustup.sh |
+    sh -s -- --add-target=$TARGET --disable-sudo -y --prefix=`rustc --print sysroot`
 before_script:
   - pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH
 script:

README.md

@@ -52,6 +52,10 @@ pub fn call() {
         bar_function();
     }
 }
+
+fn main() {
+    // ...
+}
 ```
 
 ## External configuration via environment variables