Exception in JRTIndex when using an exploded image:

Exception in thread "main" java.nio.file.FileSystemNotFoundException: /home/prrace/jdk9-client/build/linux-x86_64-normal-server-release/jdk/lib/modules/bootmodules.jimage
    at jdk.internal.jrtfs.JrtFileSystem.checkExists(JrtFileSystem.java:88)
    at jdk.internal.jrtfs.JrtFileSystem.<init>(JrtFileSystem.java:103)
    at jdk.internal.jrtfs.JrtFileSystemProvider$1.<init>(JrtFileSystemProvider.java:113)
    at jdk.internal.jrtfs.JrtFileSystemProvider.getTheFileSystem(JrtFileSystemProvider.java:113)
    at jdk.internal.jrtfs.JrtFileSystemProvider.getFileSystem(JrtFileSystemProvider.java:131)
    at java.nio.file.FileSystems.getFileSystem(FileSystems.java:221)
    at com.sun.tools.javac.file.JRTIndex.<init>(JRTIndex.java:183)
    at com.sun.tools.javac.file.JRTIndex.getSharedInstance(JRTIndex.java:61)
    at com.sun.tools.javac.code.ClassFinder.<init>(ClassFinder.java:212)