On Thu, 10 Apr 2008, Ralf Wildenhues wrote:
I've thought of this, in fact just a couple of weeks ago. It is possible to formulate SUBDIRS rules in a way that allows parallel execution of the sub makes (by something like turning each subdir into a target). However, doing so by default will certainly break lots of existing setups. That's why my current thinking is that it may be possible to introduce a new feature, say, PARALLEL_SUBDIRS = ... which would then show automake that these subdirectories really can do work in parallel. Maybe even get this functionality turned on per-project with an automake option, dunno yet.
The problem is that existing projects using SUBDIRS absolutely depend on each directory being completely processed before moving on to the next one since there is no dependency information outside of subdirectories. The only way to resolve this is by adding additional dependency knowledge, and you soon end up with everything needed for a non-recursive build. :-)
Setting up a non-recursive build project with Automake would not be such a chore if Automake knew how to ingest per-subdirectory Makefiles into the overall build, adding any necessary path information. The biggest chore related to setting up a non-recursive build is that all of the paths need to be completely specified (from the top), but modified to work with Automake.
Bob ====================================== Bob Friesenhahn [EMAIL PROTECTED], http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/