build problem on 5.x branch

[Steven Bellovin <smb%cs.columbia.edu@localhost>]

I'm trying to rebuild everything on 5.x, on two different amd64s running 5.x.  
They both failed in the same place, albeit with different errors, probably 
because of the script I'm building with.  Here's one failure.  The other 
failure was trying to build an i386 system.

#    create  EMU-DOM0/OsdEnvironment.d
CC=/usr/BUILD/tools/bin/x86_64--netbsd-gcc /usr/BUILD/tools/bin/nbmkdep -f 
OsdEnvironment.d --  -mcmodel=kernel -mno-red-zone -ffreestanding 
-fno-zero-initialized-in-bss  -O2 -std=gnu99 -fno-strict-aliasing   -Werror 
-Wall -Wno-main -Wno-format-zero-length -Wpointer-arith -Wmissing-prototypes 
-Wstrict-prototypes -Wswitch -Wshadow -Wcast-qual -Wwrite-strings 
-Wno-unreachable-code -Wno-sign-compare -Wno-pointer-sign -Wno-attributes 
-Wextra -Wno-unused-parameter  -Werror -march=i686   -Damd64 -Dx86_64 -I. 
-I/usr/BUILD/obj/sys/arch/amd64/compile/EMU-DOM0/xen-ma 
-I/usr/msrc/src/sys/../common/include -I/usr/msrc/src/sys/arch  
-I/usr/msrc/src/sys -nostdinc -DLKM -DDIAGNOSTIC -DDEBUG -DCOMPAT_30_PTHREAD 
-DMSGBUFSIZE="24576" -DMAXUSERS=32 -D_KERNEL -D_KERNEL_OPT 
-I/usr/msrc/src/sys/lib/libkern/../../../common/lib/libc/quad 
-I/usr/msrc/src/sys/lib/libkern/../../../common/lib/libc/string 
-I/usr/msrc/src/sys/lib/libkern/../../../common/lib/libc/arch/x86_64/string   
-I/usr/msrc/src/sys/external/isc/atheros_hal/dist 
-I/usr/msrc/src/sys/external/isc/atheros_hal/ic -I/usr/msrc/src/sys/dist/pf 
-I/usr/msrc/src/sys/dist/ipf  /usr/msrc/src/sys/dev/acpi/acpica/OsdEnvironment.c
/usr/msrc/src/sys/dev/acpi/acpica/OsdEnvironment.c:0: error: CPU you selected 
does not support x86-64 instruction set
/usr/msrc/src/sys/dev/acpi/acpica/OsdEnvironment.c:0: error: CPU you selected 
does not support x86-64 instruction set
nbmkdep: compile failed.

The script hasn't been touched since early November.

                --Steve Bellovin, http://www.cs.columbia.edu/~smb