[U-Boot] [PATCH] Prevent malloc with size 0

Graeme Russ graeme.russ at gmail.com
Thu Oct 21 23:10:31 CEST 2010


On 22/10/10 06:51, Mike Frysinger wrote:
> On Thursday, October 21, 2010 07:45:10 Joakim Tjernlund wrote:
>> Wolfgang Denk wrote on 2010/10/21 13:32:54:
>>> Joakim Tjernlund you wrote:
>>>>> -  if ((long)bytes < 0) return 0;
>>>>> +  if ((long)bytes <= 0) return 0;
>>>>
>>>> I think you should return some impossible ptr value =! NULL
>>>> Size 0 not really an error.
>>>
>>> It is legal for malloc() to return NULL in case of size==0,
>>> and for the sake of simplicity I recommend we do just that.
>>
>> Yes, but not very useful. Glibc does not return NULL
> 
> it is useful for malloc(0) == NULL.  the glibc behavior is downright 
> obnoxious.  we disable this for uClibc and dont see problems.  if anything, we 
> catch accidental programming mistakes which then get fixed.
> 
> why exactly do you want malloc(0) to return valid memory ?  i would rather 

I agree

> have u-boot return an error.

Is NULL what you consider to be an error - in that case, I agree as well

Besides, is not free(NULL) valid (does nothing) as well?

Regards,

Graeme


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