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Subject: Re: variables optimized out
From: Tim Kientzle <tim@kientzle.com>
In-Reply-To: <20160103145923.GA16970@becker.bs.l>
Date: Sun, 3 Jan 2016 17:17:16 -0800
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To: Bertram Scharpf <lists@bertram-scharpf.de>
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> On Jan 3, 2016, at 6:59 AM, Bertram Scharpf <lists@bertram-scharpf.de> =
wrote:
>=20
> Hi,
>=20
> On Sunday, 03. Jan 2016, 14:38:33 +0100, robbinson defau wrote:
>> Im debugging some issues in the kernel and as the kernel is compiled =
by
>> default with -O2, a lot of variables are optimized out. So i made =
changes
>> to make.conf (CFLAGS and COPTFLAGS).\
>>=20
>> All builds fine, but I get the weirdest of panics that most certainly =
not
>> happen with -O2. [...]
>=20
> I just had a look at "man make.conf" and that says:
>=20
>     CFLAGS	   (str) Controls the compiler setting when compiling C =
code.
> 		   Optimization levels other than -O and -O2 are not =
sup=E2=80=90
> 		   ported.
>=20
> At least to me this is a surprise. I'm really disappointed
> about what programming style has become common.

This comment really just means that noone has stepped
up to test the kernel when compiled with other settings and
fix the problems uncovered by it.  If you have time and
skills to do so, I'm sure patches would be appreciated...

Cheers,

Tim