> LOWER_ARCH:= ${LOWER_ARCH:C/i[4-9]86/i386/}
> MACHINE_ARCH:= ${MACHINE_ARCH:C/i[4-9]86/i386/}

Then, my LOWER_ARCH was not being set.

$  bmake show-var VARNAME=LOWER_ARCH

(nothing above)

And my ./configure's were being ran with --host==--linux. I noticed this
with pkgsrc/graphics/mng.

I think this should be:

.if defined(LOWER_ARCH)
LOWER_ARCH:=            ${LOWER_ARCH:C/i.86/i386/}
.endif

or something like that. And maybe for MACHINE_ARCH too.

   Jeremy C. Reed
   http://bsd.reedmedia.net/