Build failure xorg-drivers with Clang

[Robert]

Greetings

I am trying to build a 9.0 Stable system and am getting this error when
building xorg meta port. I have clang set up as follows

make.conf
 cat /etc/make.conf
CC=clang
CXX=clang++
CPP=clang-cpp
# added by use.perl 2012-07-09 07:23:29
PERL_VERSION=5.16.0

src.conf
CC=clang
CXX=clang++
CPP=clang-cpp

uname -a
FreeBSD pita9bsd.shasta204.local 9.0-STABLE FreeBSD 9.0-STABLE #0: Sun
Jul  8 18:52:16 PDT 2012
root at pita9bsd.shasta204.local:/usr/obj/usr/src/sys/GENERIC  i386 

The error:

In file included from xf86Helper.c:54:
In file included from ../../../hw/xfree86/os-support/xf86_OSlib.h:451:
./compiler.h:1104:24: error: invalid operand in inline asm: 'in${0:B}
($1)' __asm__ __volatile__("in%B0 (%1)" :
                       ^
./compiler.h:1104:24: error: unknown use of instruction mnemonic
without a size suffix
<inline asm>:1:2: note: instantiated into assembly here
        in (%dx)
        ^
In file included from xf86Helper.c:54:
In file included from ../../../hw/xfree86/os-support/xf86_OSlib.h:451:
./compiler.h:1104:24: error: invalid operand in inline asm: 'in${0:B}
($1)' __asm__ __volatile__("in%B0 (%1)" :
                       ^
./compiler.h:1104:24: error: unknown use of instruction mnemonic
without a size suffix
<inline asm>:1:2: note: instantiated into assembly here
        in (%dx)

In file included from xf86Helper.c:54:
In file included from ../../../hw/xfree86/os-support/xf86_OSlib.h:451:
./compiler.h:1104:24: error: invalid operand in inline asm: 'in${0:B}
($1)' __asm__ __volatile__("in%B0 (%1)" :
                       ^
./compiler.h:1104:24: error: unknown use of instruction mnemonic
without a size suffix
<inline asm>:1:2: note: instantiated into assembly here
        in (%dx)
        ^
In file included from xf86Helper.c:54:
In file included from ../../../hw/xfree86/os-support/xf86_OSlib.h:451:
./compiler.h:1104:24: error: invalid operand in inline asm: 'in${0:B}
($1)' __asm__ __volatile__("in%B0 (%1)" :
                       ^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
gmake[5]: *** [xf86Helper.lo] Error 1
gmake[4]: *** [all] Error 2
gmake[3]: *** [all-recursive] Error 1
gmake[2]: *** [all] Error 2
gmake[1]: *** [all-recursive] Error 1
gmake: *** [all-recursive] Error 1
*** [do-build] Error code 1

I just retrieved the ports this morning with portsnap fetch extract.

Any help appreciated.

Robert