[libvirt] building error

[Wen Congyang]

At 07/01/2011 04:54 AM, Eric Blake Write:
> On 06/29/2011 06:13 PM, Wen Congyang wrote:
>>> This sounds highly related to Matthias' issue:
>>> https://www.redhat.com/archives/libvir-list/2011-June/msg01484.html
> 
> Matthias was using 1.3...
> 
>>>
>>> What version of systemtap headers and gcc are you using, that produce
>>> this error?
>>
>> I use RHEL6RC, and the version of systemtap headers and gcc are:
>>
>> # rpm -qa 'systemtap*'
>> systemtap-sdt-devel-1.2-9.el6.x86_64
> 
> but you are using 1.2.  The older we go, the worse the systemtap headers
> were, apparently.  Unfortunately, I don't currently have a machine with
> headers that old to debug it myself.
> 
>>>>      }
>>>>      PROBE(CLIENT_AUTH_ALLOW, "fd=%d, auth=%d, username=%s",
>>>> -          virNetServerClientGetFD(client), REMOTE_AUTH_POLKIT, ident);
>>>> +          virNetServerClientGetFD(client), REMOTE_AUTH_POLKIT, (char *)ident);
>>>
>>> If a cast really helps matters, I'd almost rather hide it within the
>>> #define PROBE() than make callers have to worry about it, but I'm
>>> reluctant to add a cast without knowing exactly why you are hitting
>>> compilation failure.
> 
> What does STAP_PROBE3 look like in your /usr/include/sys/sdt.h?
> 

#if ! defined EXPERIMENTAL_KPROBE_SDT
....
#define STAP_PROBE3_(probe,label,parm1,parm2,parm3)			\
do STAP_SEMAPHORE(probe) {						\
  STAP_SDT_VOLATILE __typeof__((parm1)) arg1 = parm1;			\
  STAP_SDT_VOLATILE __typeof__((parm2)) arg2 = parm2;			\
  STAP_SDT_VOLATILE __typeof__((parm3)) arg3 = parm3;			\
  STAP_UNINLINE;							\
  STAP_PROBE_DATA(probe,STAP_UPROBE_GUARD,2f);				\
  __asm__ volatile ("2:\n"						\
		    STAP_NOP "/* %0 %1 %2 */" :: "g"(arg1), "g"(arg2), "g"(arg3)); \
} while (0)
....
#else /* ! defined EXPERIMENTAL_KPROBE_SDT */
...
#define STAP_PROBE3_(probe,label,parm1,parm2,parm3)			\
do STAP_SEMAPHORE(probe) {						\
  __extension__ struct {size_t arg1 __attribute__((aligned(8)));	\
	  size_t arg2 __attribute__((aligned(8)));			\
	  size_t arg3 __attribute__((aligned(8)));}			\
  stap_probe3_args = {(size_t)parm1, (size_t)parm2, (size_t)parm3};	\
  STAP_PROBE_DATA(probe,STAP_GUARD,3);					\
  syscall (STAP_SYSCALL, #probe, STAP_GUARD, &stap_probe3_args);	\
 } while (0)
...
#endif
...

#define STAP_PROBE3(provider,probe,parm1,parm2,parm3)                        \
  STAP_PROBE3_(probe,STAP_LABEL(STAP_LABEL_PREFIX(probe),STAP_COUNTER),(parm1),(parm2),(parm3))