There are actually two independent failures here.

>	I've been trying to compile various 1.2-type stuff, and I keep
>running into problems with 'Unknown Identifier Q' --- in particular,
>there is a bunch it before my kernel quits building with:

	This means your 'make' is out of date. go to usr.bin/make and 
"make && make install" there before trying to build other things. The newer
make supports the modifier "Q" which is for quoting meta-characters (have a
look at the man page after you install it.)

>/u4/src/sys/lib/libkern/adddi3.c
>-I/u4/src/sys/lib/libkern/arch/: not found

	This means that /usr/share/mk/ is out of date. go to src/share/mk
and "make install" before doing anything.

>I'm also not entirely understanding what is running at this point to
>produce this message.

	Its actually complaining because there is a variable there (specified
in the newer mk/*.mk files) which contains the name of a command; since the
variable is not defined by your older files, it evaluates to null and the
shell tries to execute "-I/u4....." as a command.

Cheers,
Phil
--
Phillip F Knaack
Systems Administrator, Information Development for Extension Audiences (IDEA)
Iowa State University Extension