Unable to build world w/o clang on 11

Greetings,
 I'm attempting to build/install world/kernel on a fresh
install of 11 on bare metal, from the bootonly iso from
10-26. I understand that clang is the default for 10+.
But had hoped to install it from ports *after* kernel/world.
I used what I *thought* was the correct direction to do this:
src.conf(5)
WITH_GCC=true
WITH_GCC_BOOTSTRAP=true
WITH_GNUCXX=true
WITHOUT_CLANG_BOOTSTRAP=true
WITHOUT_CLANG=true
WITHOUT_CLANG_IS_CC=true

But after attempting to 'make -j6 buildworld'. It failed. So while
still in /usr/src, I make clean, cd /usr/obj, and chflags -R noschg *,
then rm -rf *, followed by cd /usr/src, and make buildworld.
This too fails. I inadvertently clobbered the output I had intended
to post along with this message. But I remember it being during the
CC of rescue. If that helps any.

Thank you for all your time, and consideration.

--Chris