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Message-ID: <94fd6fb5-c87a-b02e-40bc-b2e2c99529d5@kernel.org>
Date:   Tue, 10 Jan 2023 15:19:25 +0100
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Subject: Re: [PATCH] tools/rtla: Explicitly list libtraceevent dependency
To:     Daniel Wagner <dwagner@suse.de>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230110131805.16242-1-dwagner@suse.de>
 <42d1e999-79a6-94dc-cc88-77520ddce068@kernel.org>
 <20230110140814.2yz4if2e2fasnu7t@carbon.lan>
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From:   Daniel Bristot de Oliveira <bristot@kernel.org>
In-Reply-To: <20230110140814.2yz4if2e2fasnu7t@carbon.lan>
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On 1/10/23 15:08, Daniel Wagner wrote:
> On Tue, Jan 10, 2023 at 02:55:03PM +0100, Daniel Bristot de Oliveira wrote:
>> On 1/10/23 14:18, Daniel Wagner wrote:
>>> The current libtracefs.pkg file lists the dependency on
>>> libtraceevent ("pkg-config --libs libtracefs" -> "-ltracefs
>>> -ltraceevent").
>>>
>>> Dan Nicholson's Guide to pkg-config[1] stats that "Libs: The link
>>> flags specific to this package and any required libraries that don't
>>> support pkg-config". Thus the current libtracefs.pkg is not correct.
>>>
>>> rtla is depending on libtraceevent but it doesn't express this in
>>> 'pkg-config' part to retrieve the correct build flags.
>>>
>>> In order to be able to update the "Libs:" section in the libtracefs
>>> project we need to list the dependency explicitly to avoid future linker
>>> failures.
>>
>> I am ok with it. Steve?
> 
> FWIW, this is change is also backwards compatible, meaning if you have system
> which has a libtracefs.pkg installed which lists libtraceevent in its Libs:
> section the 'pkg-config --libs libtracefs libtraceevent' command will return the
> identically string which is '-ltracefs -ltraceevent'.

Yeah, we know it. I've added both in the initial implementation, but Steven suggested
using only libtracefs because it depends on libtraceevent anyways. That is why
I am re-checking with him.

-- Daniel