WITH_DIRDEPS_BUILD on FreeBSD/arm -CURRENT?

[Paul Mather]

The good news: I just successfully completed a build and install of FreeBSD/arm with clang 3.8.0.:

FreeBSD 11.0-CURRENT #0 r296611: Sun Mar 13 03:18:03 EDT 2016
    pmather at beaglebone:/usr/obj/usr/src/sys/BEAGLEBONE-NO_WITNESS arm
FreeBSD clang version 3.8.0 (tags/RELEASE_380/final 262564) (based on LLVM 3.8.0)


Everything appears to be working fine so far. :-)

The bad news: this appears to have added 24 hours to my build time (from 41 to 65 hours for a native build). :-(

To try and cut down future build times, I tried enabling WITH_DIRDEPS_BUILD in /etc/src-env.conf.  Unfortunately, this fails immediately with a complain that /dev/filemon is not available:

	root at beaglebone:/usr/src # make buildworld
	make: "/usr/src/share/mk/meta.sys.mk" line 120:
	ERROR: The filemon module (/dev/filemon) is not loaded.


My reading of the src.conf man page leads me to believe /dev/filemon is optional with the WITH_DIRDEPS_BUILD option:


     WITH_DIRDEPS_BUILD
             Enable building in meta mode.  This is an experimental build
             feature.  For details see http://www.crufty.net/sjg/docs/freebsd-
             meta-mode.htm.

[[...]]

             As each target is made make(1) produces a meta file which is used
             to capture (and compare) the command line, as well as any command
             output.  If filemon(4) is available the meta file will also
             capture a record of files used to produce the target by tracking
             syscalls.

[[...]]


Is this in fact the case?

I have a filemon man page but no /dev/filemon.  I can't load the filemon kernel module:

	root at beaglebone:/usr/src # kldload -v filemon
	kldload: can't load filemon: No such file or directory


There is no filemon.ko in /boot/kernel.

It appears filemon is not built by default in the regular FreeBSD/arm build.  Is this an oversight, or is it because it doesn't work on FreeBSD/arm?

Has anyone used a meta-mode build on FreeBSD/arm?

Cheers,

Paul.