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Date:   Thu, 3 May 2018 10:28:23 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     "Du, Changbin" <changbin.du@intel.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        yamada.masahiro@socionext.com, michal.lkml@markovi.net,
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        arnd@arndb.de, linux-kbuild@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH v2 4/5] kernel hacking: new config DEBUG_EXPERIENCE to
 apply GCC -Og optimization
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On Thu, 3 May 2018 21:45:46 +0800
"Du, Changbin" <changbin.du@intel.com> wrote:

> > With that gcc comment, I still think CONFIG_OPTIMIZE_DEBUG is more
> > inline with what it is and understandable than
> > CONFIG_DEBUG_EXPERIENCE. The "OPTIMIZE" is the key word there.
> > 
> > -- Steve  
> What about CONFIG_CC_OPTIMIZE_FOR_DEBUGGING? We alreay have
> CONFIG_CC_OPTIMIZE_FOR_SIZE and CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE.

Yes I like that much better.

> 
> And do we need to move it to existing configuration menu "General setup->
> Compiler optimization level"? But I also want it appear in "kernel hacking"
> since this is a debug option.

I understand why you would want it by debugging, but I think it does
make more sense to be included with the above two other options, as
they are all mutually exclusive.

This brings up the topic of creating config paradigms. That is, a way
of saying "I want a debug kernel" and select one option that selects
everything you would expect. Or perhaps we should have a:

 make debug_config

that does it.

But that's a different topic. For now, I would just included it in
init/Kconfig, and not worry about it not showing up in kernel hacking.


-- Steve