./obj.${MACHINE}
./obj
/usr/obj/${PWD}
The rules for the default .OBJDIR setting are now simplified to
(and documented as) trying the chdir to the following
(if the appropriate variable is defined):
${MAKEOBJDIRPREFIX}${.CURDIR}
${MAKEOBJDIR}
${.CURDIR}
.OBJDIR can be overridden in the makefile.
<bsd.obj.mk> uses this to provide the "culled" .OBJDIR semantics
for NetBSD's /usr/src builds.
MAKEOBJDIRPREFIX & MAKEOBJDIR still can only be provided
in the environment or on make(1)'s command line.
Per discussion on tech-toolchain.
This should reduce a lot of lossage people have experienced over
the years with various .OBJDIR setups.