Both "=r" and "=g" breaks my build on i386:
$ make
CC [M] drivers/kvm/vmx.o
{standard input}: Assembler messages:
{standard input}:3318: Error: bad register name `%sil'
make[1]: *** [drivers/kvm/vmx.o] Error 1
make: *** [_module_drivers/kvm] Error 2
The reason is that setbe requires an 8-bit register but "=r" does not
constrain the target register to be one that has an 8-bit version on
i386.
According to
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10153
the correct constraint is "=q".
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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