yes, as the subject says, config(8) will now define KERNEL_BUILD at
the top of your kernel's makefile the next time you (update and
rebuild and) run config.

the proper use of DESTDIR, RELEASEDIR, KERNEL_BUILD, and BSD_PKG_MK in
your local /etc/mk.conf file can now be used to set (for example)
COPTS, CFLAGS, or anything else depending specifically on the task at
hand.

it will also write a file called config_time.src to your kernel build
directory that resembles the following:

	/* Sun Nov 17 05:37:51 2002 GMT */
	#define CONFIG_TIME     1037511471
	#define CONFIG_YEAR     2002
	#define CONFIG_MONTH    11
	#define CONFIG_DATE     17
	#define CONFIG_HOUR      5
	#define CONFIG_MINS     37
	#define CONFIG_SECS     51

this provides, at first, a possible mechanism for the inittodr()
routine to determine if your local clock has lost time.  other uses
are expected to follow.  nothing is expected to make use of all the
values, but i provided them for completeness.

note that nothing is currently *depending* on these feature, but that
you may wish to update your config binary nonetheless.  the
KERNEL_BUILD feature, in particular, is rather cool (imho).  it allows
you to define, eg, per-kernel install instructions.

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