> 	../../../../arch/sparc/sparc/pmap.c: In function `PMPID':
> 	../../../../arch/sparc/sparc/pmap.c:781: warning: assignment discards `volatile' from pointer target type

This has been fixed. In ANY CASE, it is simply a warning and doesn't
matter in the least.
> 	echo 'building rem.S from divrem.m4'
> 	building rem.S from divrem.m4
> 	(echo "define(NAME,\`.rem')define(OP,\`rem')define(S,\`true')";  cat divrem.m4) | m4 > rem.S
> 	cat: divrem.m4: No such file or directory

You needed to reinstall /usr/share/mk before building your kernel.

> and this time I got a kernel.  It appears to work fine, except that
> it's not compatible with a few user-level programs like route(8); I'm

No kidding. Your userland must be quite old.

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