Jan Lahoda reports the following:

The recent change to enable sjavac might have broken bootcycle-images
- at least the bootcycle-images build is failing for me with:
---
Creating bootcycle-build/buildtools/interim_langtools.jar
Compiling 43 files for BUILD_INTERIM_JIMAGE
Port file inaccessable:
com.sun.tools.sjavac.client.PortFileInaccessibleException:
java.io.FileNotFoundException: /localhome/langtools/.jenkins/jobs/build-jdk9-with-patch/workspace/dev/build/linux-x86_64-normal-server-release/bootcycle-build/bootcycle-build/make-support/javacservers/server.port
(No such file or directory)
Port file inaccessible.
/bin/mv: cannot move `/localhome/langtools/.jenkins/jobs/build-jdk9-with-patch/workspace/dev/build/linux-x86_64-normal-server-release/bootcycle-build/buildtools/interim_jimage_classes/_the.BUILD_INTERIM_JIMAGE_batch.log'
to `/localhome/langtools/.jenkins/jobs/build-jdk9-with-patch/workspace/dev/build/linux-x86_64-normal-server-release/bootcycle-build/make-support/failure-logs/BUILD_INTERIM_JIMAGE.log':
No such file or directory
make[4]: *** [/localhome/langtools/.jenkins/jobs/build-jdk9-with-patch/workspace/dev/build/linux-x86_64-normal-server-release/bootcycle-build/buildtools/interim_jimage_classes/_the.BUILD_INTERIM_JIMAGE_batch]
Error 1
make[3]: *** [buildtools-jdk] Error 1
make[2]: *** [bootcycle-images] Error 2

ERROR: Build failed for targets 'clean bootcycle-images' in
configuration 'linux-x86_64-normal-server-release' (exit code 2)
No indication of failed target found.
Hint: Try searching the build log for '] Error'.
Hint: If caused by a warning, try configure --disable-warnings-as-errors.

make[1]: *** [main] Error 1
make: *** [clean] Error 2
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Basically, what I was doing was:
make clean bootcycle-images