Use correct dylib extension for local os

build.sh

@@ -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 &&