[lug] new operator in C++

Stephen Queen svq at peakpeak.com
Sat Apr 27 16:20:03 MDT 2002


David Morris wrote:

> Sheesh people, try *reading* the question.
>
> New memory is never *guaranteed* to be initialized.  A few (and as far as I
> know this is the exception, NOT the rule) will initialize dynamic (or even
> static) memory allocation to zero, but it it NOT standard and if you count
> on it this is always a bug in your code.
>
> Note that just because it looks like a variable has been initialized, does
> not mean it has been initialized....the default state of memory is zero,
> and there are many cases where you will get the default state of memory
> rather than whatever was there last....in fact, this is more normal now
> that to get some old contents of memory, which is why programs can
> sometimes get by *without* initializing variables.
>
> Never rely on C/C++ to provide a valid initial value, or you will
> eventually come up with one of the more annoying bugs in existance.
>
> Hope this helps...
>
> --David
>
> --
> "I might not agree with what you say,
>     but I will defend to the death your right to say it!"
>   --Voltaire
>
> Quoting Stephen Queen <svq at peakpeak.com>:
>
> > In using the new operator in C++ I cannot find whether it is
> > guaranteed
> > to initialize the new memory to zero or not. In playing with it, it
> > looks like it does, but that might be coincidence. Does anyone know a
> > source of information on the net regarding this? Another question
> > regarding sources of information on C++. man has section 3 which is a
> > good source of information for regular C. Does anyone know of anything
> > like that for C++? It sure would come in handy now and then.
> >
> > Thanks,
> > Steve Queen
> >
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Yes it does help. Thanks for taking the time to answer.




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