Re: gcc 3.0.2/kernel details (-O issue)

From: J.A. Magallon (jamagallon@able.es)
Date: Sat Dec 22 2001 - 18:54:28 EST


On 20011222 Pavel Machek wrote:
>Hi!
>
>> > It is interesting that 2.2 can be done with -O. Also I'd expect
>> > errors during compilation and not silent crash...
>>
>> Well, you certainly won't get errors, because compiler optimizations
>> shouldn't change expected syntax.
>>
>> -O2 is the standard optimization level for the kernel; everything is
>> compiled via it. When developers test their code, nuances that the
>> optimization introduce are accepted. Removing the optimization may
>> break those expectations. Thus the kernel requires it.
>
>Huh? Those expectations are *bugs*.
>
>Kernel will not link without optimalizations because it *needs*
>inlining. Any else dependency is a *bug*.
> Pavel

Wouldn't it be better to mark such places with something like
#pragma inline, if gcc allows it, than relaying on gcc guesses about
inlining, or options activated in O2 ?

-- 
J.A. Magallon                           #  Let the source be with you...        
mailto:jamagallon@able.es
Mandrake Linux release 8.2 (Cooker) for i586
Linux werewolf 2.4.17-beo #1 SMP Fri Dec 21 21:39:36 CET 2001 i686
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