.\" $FreeBSD: head/tools/build/options/WITH_DIRDEPS_BUILD 298007 2016-04-14 22:00:49Z bdrewery $
This is an experimental build system.
For details see
http://www.crufty.net/sjg/docs/freebsd-meta-mode.htm.
Build commands can be seen from the top-level with:
.Dl make show-valid-targets
The build is driven by dirdeps.mk using
.Va DIRDEPS
stored in
Makefile.depend files found in each directory.
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The build can be started from anywhere, and behaves the same.
The initial instance of
.Xr make 1 
recursively reads
.Va DIRDEPS
from Makefile.depend
computing a graph of tree dependencies from the current origin.
Setting
.Va NO_DIRDEPS
will skip checking dirdep dependencies and will only build in the current
and child directories.
.Va NO_DIRDEPS_BELOW
will skip building any dirdeps and only build the current directory.
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This also utilizes the
.Va WITH_META_MODE
logic for incremental builds.
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The build will hide commands ran unless
.Va NO_SILENT
is defined.
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Note that there is currently no mass install feature for this.
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