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SubjectRe: Possible GCC contamination of Linux
On Wed, 22 Sep 1999, Artur Skawina wrote:

> Kurt Garloff wrote:
> >
> > a patch which adds -fno-builtins to the Makefile and makes the abs() work.
>
> why?
>

So you can compile a i386 or i486 kernel with a 'C' compiler that was
built on a i686 machine. It took me a week to find the reason why
a kernel, configured to run on a 486 (or even 386) would crash on
the boot of a 486.

>
> > Wait: What about the speed of builtin memcpy and the routines provided by
> > the kernel? I think I remember a discussion about his. Anybody?
>
> depends on cpu i guess. The builtins generate noticably better code when
> the length is constant though.
>

The memcpy and other routines are in the architecture-specific directories
in cases where processors offer certain advantages.

The only built-in I found used was abs(). It was the '486 killer.


Cheers,
Dick Johnson
**** FILE SYSTEM WAS MODIFIED ****
Penguin : Linux version 2.3.13 on an i686 machine (400.59 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.


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