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From: Ian Collins <ian-news@hotmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Lets put it another way
Date: Tue, 24 May 2011 22:27:05 +1200
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On 05/24/11 09:20 PM, Paul wrote:
>
> "Ian Collins"<ian-news@hotmail.com>  wrote in message
> news:940g82Ft2pU20@mid.individual.net...
>> On 05/24/11 01:14 PM, Paul wrote:
>>> Ok in connection to my previous post, lets remove the null pointer issue
>>> and
>>> consider this:
>>>
>>> #include<iostream>
>>>
>>> typedef int (*pparr)[3];
>>>
>>> int main(){
>>>    pparr p1 = (pparr)new int[3];
>>>    pparr p2= p1;
>>>    delete[] p1;
>>>    std::cout<<   *p2<<std::endl;
>>
>> UB yet again.
>>
>>>    std::cout<<   typeid(*p2).name();
>>> }
>>>
>>>
>>> In the last 2 lines does an array type object exist, even though there is
>>> no
>>> array object?
>>
>> No.
>>
>>> If not what is the object that stores the address and is interpreted as
>>> an
>>> array type by the typeid expression?
>>
>> The typeid and sizeof operators do not evaluate their expression (unless
>> in case of typeid the type is polymorphic).  So no object is required.
>>
> You do not seem to understand the question.

You do not appear to understand the answer.

> I said ..if not what is the object that stores the address?
> So what is this object? Do you know?

There isn't an object.  The compiler knows the type of *p2.  You may as 
well have written

#include <iostream>
#include <typeinfo>

typedef int (*pparr)[3];

int main(){
   pparr p2;
   std::cout << typeid(*p2).name() << std::endl;
}


-- 
Ian Collins