[Freeciv-Dev] Re: malloc warning (PR#842)

[Gaute B Strokkenes <gs234@xxxxxxxxx>]

On 11 Jul 2001, falk.hueffner@xxxxxxxxxxxxxxxxxxxxxxxx wrote:
> Gaute B Strokkenes <gs234@xxxxxxxxx> writes:
> 
>> On Wed, 11 Jul 2001, ChrisK@xxxxxxxx wrote:
>> > CVS 11 JUL 2001 GTK+ Linux i386
>> > 
>> > I've got a 
>> > 
>> > 2: Warning: malloc with size 0 at line 750 of unittools.c
>> > 2: Letzte Mitteilung 2mal wiederholt.
>> > 
>> > Reproducible. Savegame is here:
>> > 
>> > http://www.enter.de/~c.knoke/bugs/malloc.sav.gz
>> > 
>> > Login as chris, start game, terminate client.
>> 
>> Please try the following patch (untested):
> 
> I don't see the point. What's the problem with allocating 0 bytes?
> It doesn't do any harm.

Wrong.  malloc(0) brings you into the land of implementation-defined,
as opposed to undefined, behaviour.  Even worse, some mallocs just
crap out anyway.  This is why fc_malloc() guards against this case,
and gives a warning.

Usually malloc'ing zero bytes is indicative of a thinko of some sort,
so it is useful to give a warning.  My patch just avoids the warning.

-- 
Big Gaute                               http://www.srcf.ucam.org/~gs234/
GOOD-NIGHT, everybody..  Now I have to go administer FIRST-AID
 to my pet LEISURE SUIT!!