Error
warning: ‘includeantruntime’ was not set, defaulting to build.sysclasspath=last; set to false for repeatable builds
Reason
It is caused by a misfeature introduced in Ant 1.8
Include attribute includeantruntime and set it to false as shown below
Solution 1
<javac .... includeantruntime="false" .../>
Solution 2
In case if your project contains many build.xml files which one cannot, or prefers not to, edit
Use presetdef add these lines in top of build.xml file
<presetdef name="javac"> <javac includeantruntime="false" /> </presetdef>
If your projects do actually need ant runtime libraries, you can either add them explicitly to your build files OR set includeantruntime=”true”
<javac destdir="out" includeantruntime="true"> <src path="foo.java" /> <src path="bar.java" /> </javac>
Now all subsequent javac tasks will essentially inherit includeantruntime=”false”