'Redefine the macros likely() and unlikely to no-ops, depending on
condition \'cond\''

def undef_builtin_expect(self, cond):

    self.putln(('#if    %s' % cond))
    self.putln('                #undef    likely')
    self.putln('                #undef    unlikely')
    self.putln('                #define    likely(x)            (x)')
    self.putln('                #define    unlikely(x)    (x)')
    self.putln('#endif')
