Re: removing bcopy... because it's half broken

[Matthias-Christian Ott]

Adrian Bunk wrote:

> On Sun, Jan 09, 2005 at 12:19:09PM -0800, Linus Torvalds wrote:
>  
>
> > On Sun, 9 Jan 2005, Arjan van de Ven wrote:
> >    
> >
> > > Instead of fixing this inconsistency, I decided to remove it entirely,
> > > explicit memcpy() and memmove() are prefered anyway (welcome to the 1990's)
> > > and nothing in the kernel is using these functions, so this saves code size
> > > as well for everyone.
> > >      
> > The problem is that at least some gcc versions would historically generate
> > calls to "bcopy" on alpha for structure assignments. Maybe it doesn't any
> > more, and no such old gcc versions exist any more, but who knows?
> > ...
> >    
>
> include/asm-alpha/string.h says:
>
>  /*
>   * GCC of any recent vintage doesn't do stupid things with bcopy.
>   * EGCS 1.1 knows all about expanding memcpy inline, others don't.
>   *
>   * Similarly for a memset with data = 0.
>   */
>
>
> And Arjan's patch is pretty low-risk:
>
> If it breaks on any architecture with any supported compiler (>= 2.95), 
> it will break at compile time and there will pretty fast be reports of 
> this breakage in which case it would be easy to revert his patch.
>
>
>  
>
> > 		Linus
> >    
>
> cu
> Adrian
>
>  
Jep and most people are using a newer gcc and newer glibc. Linux has to 
stay up2date, so I think it's the best choise to create a modern and 
clean (without broken functions) OS.

Matthias-Christian Ott
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