Both "product" and "build" ordering are rampant in /usr/src. This document
is not indented to be as strict as style(9) as historically BSD hasn't been
as consistent about Makefile as C code. Also there are too many variations,
exceptions and allowances in out existing Makefile style to be strict.
However there is a general level of consensus on what the general BSD style
of our Makefiles is. This manpage documents that "smell".
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