Re: ANNOUNCE: mdadm 3.0 - A tool for managing Soft RAID under Linux

[Bill Davidsen <davidsen@tmr.com>]

Neil Brown wrote:
> On Wednesday June 3, babydr@baby-dragons.com wrote:
>   
>>  	Hello Neil ,  I am getting a interesting Error during compiling 3.0 .
>>  	Is there a particular version of kernel that 3.0 is supposed to be 
>> compiled with ?
>>     
>
> This has nothing to do with kernel version.  You must be using a
> different compiler version - it is picking up an error that might
> didn't.
>
> The fix is below.
> Thanks,
> NeilBrown
>
>
>   
>>  		Tia ,  JimL
>>
>> gcc -Wall -Werror -Wstrict-prototypes -ggdb -DSendmail=\""/usr/sbin/sendmail 
>> -t"\" -DCONFFILE=\"/etc/mdadm.conf\" -DCONFFILE2=\"/etc/mdadm/mdadm.conf\"   -c 
>> -o super-intel.o super-intel.c
>> cc1: warnings being treated as errors
>> super-intel.c: In function 'mark_failure':
>> super-intel.c:3632: warning: comparison is always false due to limited range of 
>> data type
>> make: *** [super-intel.o] Error 1
>>
>>     
>
> commit 4291d691b66f65695b5b4be22b80fd00da73b544
> Author: NeilBrown <neilb@suse.de>
> Date:   Thu Jun 4 12:29:21 2009 +1000
>
>     super-intel: fix test on failed_disk_num.
>     
>     We sometimes set failed_disk_num to ~0.
>     However we cannot test for equality with that as  failed_disk_num
>     is 8bit and ~0 is probably 32bit with lots of 1's.
>     So test if ~failed_disk_num is 0 instead.
>     
>     Reported-By: "Mr. James W. Laferriere" <babydr@baby-dragons.com>
>     Signed-off-by: NeilBrown <neilb@suse.de>
>
> diff --git a/super-intel.c b/super-intel.c
> index 73fe5fa..7e2a086 100644
> --- a/super-intel.c
> +++ b/super-intel.c
> @@ -3629,7 +3629,7 @@ static int mark_failure(struct imsm_dev *dev, struct imsm_disk *disk, int idx)
>  
>  	disk->status |= FAILED_DISK;
>  	set_imsm_ord_tbl_ent(map, slot, idx | IMSM_ORD_REBUILD);
> -	if (map->failed_disk_num == ~0)
> +	if (~map->failed_disk_num == 0)
>  		map->failed_disk_num = slot;
>  	return 1;
>  }
>   

I still don't think this is really portable, the zero should be cast 
using typeof.

-- 
Bill Davidsen <davidsen@tmr.com>
  Even purely technical things can appear to be magic, if the documentation is
obscure enough. For example, PulseAudio is configured by dancing naked around a
fire at midnight, shaking a rattle with one hand and a LISP manual with the
other, while reciting the GNU manifesto in hexadecimal. The documentation fails
to note that you must circle the fire counter-clockwise in the southern
hemisphere.