Message-ID: <19980520213335.30170@cerebro.laendle>
Date: Wed, 20 May 1998 21:33:35 +0200
From: Marc Lehmann <pcg AT goof DOT com>
To: beastium <beastium-list AT Desk DOT nl>
Subject: Re: flags for linux-kernel-kompiling
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References: <Pine DOT A41 DOT 3 DOT 95 DOT 980519184645 DOT 65384A-100000 AT stud2 DOT tuwien DOT ac DOT at>
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In-Reply-To: <Pine.A41.3.95.980519184645.65384A-100000@stud2.tuwien.ac.at>; from Matthias Weiss on Tue, May 19, 1998 at 06:55:51PM +0200
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On Tue, May 19, 1998 at 06:55:51PM +0200, Matthias Weiss wrote:
> hi!
> 
> If I compile the linux kernel where do I change the compiling flags, is it
> in /usr/src/linux/Makefile at the line
> 
> HOSTCFLAGS =

You change CFLAGS, and maybe you should
have a look at arch/i386/Makefile and remove the -m486 and -malign-* options.

> What flags would you recommend to set for best performance and stability
> (I'm running kernel source version 2.0.29)????

2.0.29 is too buggy to be compiled with pgcc at the moment. You should
upgrade to 2.0.34 anytime soon. "-O6" usually is ok for CFLAGS.

> I've had some problems with changing flags for the linux kernel
> compilation myself and would like some advice. 
> 
> Currently, I can compile 2.1.102 with -O2 and -m486 (standard
> flags) without any problems. 
> 
> I can compile with -O6 and -m486 as well, (-O6 in /usr/src/linux/Makefile
> and in /usr/src/linux/arch/i386/boot/Makefile.  -m486 in
> /usr/src/linux/arch/i386/Makefile)  but compiling without -m486 or with
> -mcpu=pentium or -mcpu=pentiumpro gives some big pain (this is on a P2

A P2? ;)

> But in the boot sequence, after reaching sysvinit (2.74, which I've

There must be a bug somewhere, indeed. At the moment 2.1.102 doesn't even
boot with 2.7.2.3 on my machine :(. I have no idea wether the bug is in the
compiler or the kernel.

> I've read in the pgcc FAQ that the linux kernel shouldn't have any
> problems running when compiled with -O6 and -mcpu=pentium, is anyone on
> this list doing this successfully?

Yes, me. Until 2.1.99+, it seemed to work fine (I do this since 1.3.x).
Recently, I upgraded my system and now have all the newest hardware, kernels
compiled with 2.7.2.3 exhibit different errors than kernels compiled with
pgcc ;(

> As a sidenote, will a pgcc patch for egcs-1.0.3a be out soon? 

Hmm... I try...

> > With -O6 -march=pentiumpro, I have the same problem, unless I include the 
> > option -fno-risc.
> 
> Yup, that made it work. 

Thats fine!
      
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    The choice of a GNU generation                        |
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