MKDEBUG_LIB=yes breaks prep build

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

I've recently switched to building everything with MKDEBUG=yes and
MKDEBUG_LIB=yes.  Of the ports I build, "prep" fails with:

[...]
=======  8 extra files in DESTDIR  =========
Files in DESTDIR but missing from flist.
File is obsolete or flist is out of date ?
------------------------------------------
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/cirrus_alpine.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/cirrus_drv.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/kbd_drv.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/mga_drv.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/mouse_drv.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/s3_drv.so.0.debug
./usr/libdata/debug/usr/X11R7/lib/modules/drivers/ws_drv.so.1.debug
./usr/libdata/debug/usr/X11R7/lib/modules/libint10.so.0.debug
=========  end of 8 extra files  ===========
*** [checkflist] Error code 1
nbmake[2]: stopped in /x/current/src/distrib/sets
[...]

I build with the following command line:

./build.sh -U -m prep -T /r0/build/current/tools/amd64 -O /r0/build/current/obj/prep -D /r0/build/current/DEST/prep -R /r0/build/current/REL -X ../xsrc -x -u -j 9 -V USE_PIGZGZIP=yes -V MKDEBUG=yes -V MKDEBUG_LIB=yes -V MKCROSSGDB=yes tools release iso-image

I would think that at least a few of those drivers listed should be MI,
so it's puzzling they don't seem to be in the lists used for "prep".

Thanks for your attention.

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