Re: Vector new bug ??

[André Pönitz]

Günter Neiß <address@hidden> wrote:
>  I found the following bug:
> 
>  Using some templates that uses:
> 
>  template<class T>
>  ....
>    t * p = new T[ size ];
> 
> 
>  Everything works fine, as long as 'size' isn't 0.

Which version of g++ is that?

It seems to work in 2.95.2

>   if( size == 0 )
>     p = NULL;
>    else
>     p = new T[ size ];
>  ...
> 
>  But I assume that this behaviour should already implemented inside
> (vector) new !

Note that there is a difference between an array of zero items and a null
pointer.
 
>  I am not shure what the C++ standard says to this, but if it don't
>  specify it, I assume returning NULL should be the default behaviour in
>  this case ( as malloc( 0 ) does ).

Your assumption is wrong. From CD2 (similar wording in Final under 5.3.4.7)

5.3.4
8 When the value of the expression in a direct-new-declarator  is  zero,
  the  allocation  function  is called to allocate an array with no ele-
  ments.  The pointer returned by the  new-expression  is  non-null  and
  distinct from the pointer to any other object.

Andre'

PS:

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> mit S/MIME

[Is this really necessary?]

-- 
André Pönitz .............................................. address@hidden