[U-Boot-Users] [PATCH 02/17] examples/eepro100_eeprom: Fix memcpy to return destination pointer

[Wolfgang Denk <wd@denx.de>]

In message <20080518222019.GC19480@game.jcrosoft.org> you wrote:
>
> > >  static inline void *memcpy(void *dst, const void *src, unsigned int len)
> > >  {
> > >  	char *ret = dst;
> > > +
> > >  	while (len-- > 0) {
> > >  		*ret++ = *((char *)src);
> > >  		src++;
> > >  	}
> > > -	return (void *)ret;
> > > +
> > > +	return (void *)dst;
> > 
> > While technically correct, this is bogus. We have a variable ret, but
> > we don't return it. And we have a variable dst, but we don't use it as
> > destination pointer.
> > 
> > Please change the
> > 	*ret++ = *((char *)src);
> > into
> > 	*dst++ = *((char *)src);
> > and leave all the rest.
> You can not do this because dst is a void

Why not? src is void, too.

we can do this
> 
> 	char *tmp = dst;
> 
> 	while (len-- > 0) {
> 		*tmp++ = *((char *)src);
> 		src++;
> 	}
> 
> 	return (void *)dst;

This is not a bit better.


Best regards,

Wolfgang Denk

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