Re: [PATCH v2] tools: perf: fix linker error when libelf config is disabled

Sudeep Holla
2017-01-04T17:36:38Z

On 04/01/17 17:19, Jiri Olsa wrote:
> On Wed, Jan 04, 2017 at 04:18:10PM +0000, Sudeep Holla wrote:
>>
>>
>> On 04/01/17 16:08, Sudeep Holla wrote:
>>>
>>>
>>> On 04/01/17 16:06, Jiri Olsa wrote:
>>>> On Wed, Jan 04, 2017 at 03:56:03PM +0000, Sudeep Holla wrote:
>>>>> When libelf is disabled in the configuration, we get the following
>>>>> linker error:
>>>>> LINK libperf-jvmti.so
>>>>> ld: cannot find -lelf
>>>>> Makefile.perf:515: recipe for target 'libperf-jvmti.so' failed
>>>>>
>>>>> Jiri pointed out that both librt and libelf are not really required. So
>>>>> this patch fixes the linker error by getting rid of unwanted libraries
>>>>> in the linker stage.
>>>>>
>>>>> Fixes: d4dfdf00d43e ("perf jvmti: Plug compilation into perf build")
>>>>
>>>> hum, AFAICS it linked -lelf and -lrt even before right? ;-)
>>>>
>>>
>>> Yes, sorry I forgot to remove that and trace it back the actual commit.
>>>
>>
>> Having looked at it again, it looks new additions in the above commit.
>> It may be a copied from somewhere else but I can't trace it back :(.
>> I need your help if you want to get rid of that ;)
>
> I think it's this one:
> 209045adc2bb perf tools: add JVMTI agent library

Thanks for that, I would never have figured this out myself. Will fix
that and send out v3.

--
Regards,
Sudeep