kotlin-fork/compiler/testData/integration/ant/jvm/languageVersion/build.xml

<project name="Ant Task Test" default="build">
    <taskdef resource="org/jetbrains/kotlin/ant/antlib.xml" classpath="${kotlin.lib}/kotlin-ant.jar"/>

    <target name="build">
        <kotlinc src="${test.data}/main.kt" output="${temp}/hello.jar">
            <compilerarg line="-language-version 1.5"/>
        </kotlinc>
    </target>
</project>