Building with MKLLVM and HAVE_LLVM

[coypu%SDF.ORG@localhost]

I'm attempting to build NetBSD-current with MKLLVM=yes, HAVE_LLVM=yes.
Using Fedora 24 and 23.

After a couple of fixes from Riastradh I've needed the following:
in sys/sys/exec_elf.h:

-#ifdef   _BSD_SIZE_T_
-typedef  _BSD_SIZE_T_    size_t;
-#undef   _BSD_SIZE_T_
-#endif

gcc compilation is failing a lot, I needed to make many changes along
the lines of:
-#include <bits/hash_bytes.h>
+#include <g++/bits/hash_bytes.h>

(Basically every include with bits in it has to be g++/bits)
And:

-#include <bits/c++config.h>
+#include <bits/c++config>

It's tedious and most of the changes are to generated files, so I've attempted
with MKGCC=no.

Now I'm stuck with this error:

--- dependall-HZ ---
#   compile  HZ/citrus_prop.pico
/home/fly/src2/netbsd-src/obj/tooldir.Linux-4.5.0-0.rc2.git2.1.fc24.x86_64-x86_64/bin/x86_64--netbsd-clang
-O2  -std=gnu99      -m32 -m32
--sysroot=/home/fly/src2/netbsd-src/obj/destdir.amd64
-I/home/fly/src2/netbsd-src/lib/libc/citrus -DLOCALEMOD_MAJOR=5
-DLIBC_SCCS  -c    -fPIC
/home/fly/src2/netbsd-src/lib/libc/citrus/citrus_prop.c -o
citrus_prop.pico
--- dependall-UTF1632 ---
/home/fly/src2/netbsd-src/obj/tooldir.Linux-4.5.0-0.rc2.git2.1.fc24.x86_64-x86_64/bin/x86_64--netbsd-ld:
skipping incompatible
/home/fly/src2/netbsd-src/obj/destdir.amd64/usr/lib/libc.so when
searching for -lc
/home/fly/src2/netbsd-src/obj/tooldir.Linux-4.5.0-0.rc2.git2.1.fc24.x86_64-x86_64/bin/x86_64--netbsd-ld:
skipping incompatible
/home/fly/src2/netbsd-src/obj/destdir.amd64/usr/lib/libc.a when
searching for -lc
/home/fly/src2/netbsd-src/obj/tooldir.Linux-4.5.0-0.rc2.git2.1.fc24.x86_64-x86_64/bin/x86_64--netbsd-ld:
cannot find -lc
x86_64--netbsd-clang: error: linker command failed with exit code 1 (use
-v to see invocation)
*** [libUTF1632.so.5.0] Error code 1

Any ideas?