Re: Large block device patch, part 1 of 9

[Daniel Phillips <phillips@arcor.de>]

On Tuesday 03 September 2002 12:01, Neil Brown wrote:
> On Tuesday August 27, bcrl@redhat.com wrote:
> > On Tue, Aug 27, 2002 at 03:23:04PM +0000, Pavel Machek wrote:
> > > Hi!
> > > 
> > > > Then the following works properly without ugly casts or warnings:
> > > > 
> > > > 	__u64 val = 1;
> > > > 
> > > > 	printk("at least "PFU64" of your u64s are belong to us\n", val);
> > > 
> > > Casts are ugly but this looks even worse. I'd go for casts.
> > 
> > Casts override the few type checking abilities the compiler gives us.  At 
> > least with the PFU64 style, we'll get warnings when someone changes a variable 
> > into a pointer without remembering to update the printk.
> > 
> 
> You could have the best of both worlds with:
> 
> static inline long long llsect(sector_t sector) { return (long long)sector;}
> 
> and then
>    printk("The sector number is %Lu.", llsect(sect_num));
> 
> Effectively, this is a type-safe cast.  You still get the warning, but
> it looks more like the C that we are used to.

We've been through this before.  Last time, the winning solution was:

   printk("at least %lli of your u64s are belong to us\n", (long long) sect_num);

and I expect it will be this time too.  It's just a printk!  Who cares if it
wastes a few bytes.  It's even conceivable that if we use this idiom heavily
enough, some gcc boffin will take the time to optimize away the useless
conversions.

-- 
Daniel