Thanks Marcelo, "this is just how Maven works (unfortunately)" answers my question.
Another related question: I tried to use `mvn scala:cc` and discovered that it only seems to work scan src/main and src/test directories (according to its docs <http://scala-tools.org/mvnsites/maven-scala-plugin/usage_cc.html>), and so can only be run from within submodules, not from the root directory. I'll add a note about this to building-spark.html unless there is a way to do it for all modules / from the root directory that I've missed. Let me know! On Tue Dec 02 2014 at 5:49:58 PM Marcelo Vanzin <van...@cloudera.com> wrote: > On Tue, Dec 2, 2014 at 4:40 PM, Ryan Williams > <ryan.blake.willi...@gmail.com> wrote: > >> But you only need to compile the others once. > > > > once... every time I rebase off master, or am obliged to `mvn clean` by > some > > other build-correctness bug, as I said before. In my experience this > works > > out to a few times per week. > > No, you only need to do it something upstream from core changed (i.e., > spark-parent, network/common or network/shuffle) in an incompatible > way. Otherwise, you can rebase and just recompile / retest core, > without having to install everything else. I do this kind of thing all > the time. If you have to do "mvn clean" often you're probably doing > something wrong somewhere else. > > I understand where you're coming from, but the way you're thinking is > just not how maven works. I too find annoying that maven requires lots > of things to be "installed" before you can use them, when they're all > part of the same project. But well, that's the way things are. > > -- > Marcelo >
