[PATCH] ccan: Fix calling memset with zero length parameter.

[Rusty Russell]

Volker Lendecke <Volker.Lendecke at SerNet.DE> writes:
> On Thu, Jul 11, 2013 at 02:04:00PM +0200, Andreas Schneider wrote:
>>   2381                   from ../lib/ccan/likely/likely.h:5,
>>   2382                   from ../lib/ccan/tally/tally.c:4:
>>   2383  In function 'memset',
>>   2384      inlined from 'tally_histogram' at ../lib/ccan/tally/tally.c:513:9:
>>   2385  /usr/include/bits/string3.h:81:30: warning: call to 
>> '__warn_memset_zero_len' declared with attribute warning: memset used with 
>> constant zero length parameter; this could be due to transposed parameters 
>> [enabled by default]
>>   2386         __warn_memset_zero_len ();
>>   2387                                ^
>> 
>> I didn't see how could could be always 0 here but probably count = 0 is what 
>> the compiler sees and warns about.
>
> To avoid an additional if-statement, what about the
> alternative attached patch?

Yes, I like this.  Though it's really a false positive from GCC.

I've applied the same patch to upstream CCAN.

Thanks!
Rusty.