Eclipse 4.5 code formatting is not backward compatible with Eclipse 4.4 (“Luna”) (see [1] for more details). And only Eclipse 4.5 will have jdk9 support. As such, the JVMCI code base should be updated such that the `mx eclipseformat` command can use Eclipse 4.5 to ensure consistent code format in JVMCI.

[1] http://eclipse-n-mati.blogspot.ch/2015/06/eclipse-mars-how-to-switch-back-to.html