When attempting to build Xen on x86_64 FC4 platform, using the May 26 22:03 xen-unstable-src.tgz and pulling the latest BK tree:

gcc -nostdinc -fno-builtin -fno-common -fno-strict-aliasing -iwithprefix include -Wall -Werror -Wno-pointer-arith -pipe -I/tmp/xen- unstable/xen/include -I/tmp/x en-unstable/xen/include/asm-x86/mach- generic -I/tmp/xen-unstable/xen/include/asm -x86/mach-default -O3 - fomit-frame-pointer -msoft-float -m64 -mno-red-zone -fpic -fno-reorder- blocks -fno-asynchronous-unwind-tables -DNDEBUG -c cpu/common.c -o cpu/common.o cc1: warnings being treated as errors cpu/common.c: In function ‘early_cpu_detect’: cpu/common.c:209: warning: pointer targets in passing argument 2 of ‘cpuid’ diff er in signedness cpu/common.c:209: warning: pointer targets in passing argument 3 of ‘cpuid’ diff er in signedness cpu/common.c:209: warning: pointer targets in passing argument 4 of ‘cpuid’ diff er in signedness cpu/common.c:209: warning: pointer targets in passing argument 5 of ‘cpuid’ diff er in signedness cpu/common.c: In function ‘generic_identify’: cpu/common.c:241: warning: pointer targets in passing argument 2 of ‘cpuid’ diff er in signedness cpu/common.c:241: warning: pointer targets in passing argument 3 of ‘cpuid’ diff er in signedness cpu/common.c:241: warning: pointer targets in passing argument 4 of ‘cpuid’ diff er in signedness cpu/common.c:241: warning: pointer targets in passing argument 5 of ‘cpuid’ diff er in signedness cpu/common.c:250: warning: pointer targets in passing argument 3 of ‘cpuid’ diff er in signedness make[3]: *** [cpu/common.o] Error 1 make[3]: Leaving directory `/tmp/xen-unstable/xen/arch/x86' make[2]: *** [/tmp/xen-unstable/xen/xen] Error 2 make[2]: Leaving directory `/tmp/xen-unstable/xen' make[1]: *** [xen] Error 2 make[1]: Leaving directory `/tmp/xen-unstable' make: *** [world] Error 2

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