message: Use correct dylib extension for local os
diff: @@ -2,7 +2,17 @@ cargo build || exit 1
  cd examples/
  -RUSTC="rustc -Zcodegen-backend=$(pwd)/../target/debug/librustc_codegen_cranelift.so -L crate=. --crate-type lib"
  +unamestr=`uname`
  +if [[ "$unamestr" == 'Linux' ]]; then
  + dylib_ext='so'
  +elif [[ "$unamestr" == 'Darwin' ]]; then
  + dylib_ext='dylib'
  +else
  + echo "Unsupported os"
  + exit 1
  +fi
  +
  +RUSTC="rustc -Zcodegen-backend=$(pwd)/../target/debug/librustc_codegen_cranelift.$dylib_ext -L crate=. --crate-type lib"
  $RUSTC mini_core.rs --crate-name mini_core &&
  $RUSTC example.rs &&
  