Unable to build FreeBSD xdev tools for ARM on FreeBSD 10.0-CURRENT

[KCasey42]

Attempting to build the cross tools
# cd /usr/src
# make xdev XDEV=arm XDEV_ARCH=arm

on the following system

# uname -a
FreeBSD xxx.xxx.xxx 10.0-CURRENT FreeBSD 10.0-CURRENT #0 r240450: Thu 
Sep 13 05:49:13 PDT 2012 
root at xxx.xxx.xxx:/usr/src/sys/amd64/compile/silver  amd64

using

# clang --version
FreeBSD clang version 3.2 (trunk 162107) 20120817
Target: x86_64-unknown-freebsd10.0
Thread model: posix

produces the following error

clang  -O -pipe  -fpic -fvisibility=hidden -DVISIBILITY_HIDDEN 
-std=gnu99 -Qunused-arguments  -c 
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c -o 
__sync_fetch_and_add_4.o
In file included from 
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c:6:
/usr/src/lib/libcompiler_rt/__sync_fetch_and_op_n.h:34:1: error: conflicting
       types for '__sync_fetch_and_add_4'
NAME(volatile TYPE *ptr, TYPE value)
^
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c:2:15: note: 
expanded from
       macro 'NAME'
#define NAME            __sync_fetch_and_add_4# clang --version
FreeBSD clang version 3.2 (trunk 162107) 20120817
Target: x86_64-unknown-freebsd10.0
Thread model: posix

                         ^
/usr/src/lib/libcompiler_rt/__sync_fetch_and_op_n.h:34:1: note:
       '__sync_fetch_and_add_4' is a builtin with type 'int (volatile 
int *, int,
       ...)'
NAME(volatile TYPE *ptr, TYPE value)
^
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c:2:15: note: 
expanded from
       macro 'NAME'
#define NAME            __sync_fetch_and_add_4
                         ^
In file included from 
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c:6:
/usr/src/lib/libcompiler_rt/__sync_fetch_and_op_n.h:34:1: error: 
definition of
       builtin function '__sync_fetch_and_add_4'
NAME(volatile TYPE *ptr, TYPE value)
^
/usr/src/lib/libcompiler_rt/__sync_fetch_and_add_4.c:2:15: note: 
expanded from
       macro 'NAME'
#define NAME            __sync_fetch_and_add_4
                         ^
2 errors generated.
*** [__sync_fetch_and_add_4.o] Error code 1

Stop in /usr/src/lib/libcompiler_rt.
*** [lib/libcompiler_rt__PL] Error code 1

Stop in /usr/src.
*** [libraries] Error code 1

Stop in /usr/src.
*** [_xi-libraries] Error code 1

Stop in /usr/src.
*** [xdev] Error code 1

Stop in /usr/src.