Re: Ada Pointer Size Problem

[Martin Krischik <krischik@users.sourceforge.net>]

Adrien Plisson wrote:

> Martin Krischik wrote:
>> Jeffrey Carter wrote:
>>>Every C
>>>I've ever used allowed a pointer or address to be stored in an int.
>> 
>> Then you have used C only in a very small windows of opportunity. You
>> have missed the intersting world of the 80286 with it's host of very
>> interesting memory models.
> 
> in C and C++ on most 32 bits platforms:
> sizeof( void *) == sizeof( long ) == sizeof( int ) == 4
> that's why he is allowed to store pointers in an int. to use 64 bit wide
> integers, you have to use __int64.

Only the the computers I bought recently are 64 bit and - if you belive in
Moors law - transition to greater 2 GB of main memory for general use
should happen within the next 18 month.

BTW: You should store pointers in intptr_t or uintptr_t.

And you should not use datatypes which start with two "_" - If you need 64
bits you should use int64_t.

> so I don't think he missed the 80286 and its bunch of wonderful memory
> models...

There was a bit of sarcasm on my side here.

>> And you have not yet arrived the great new world of 64 bit computing -
>> where a pointer is twice the size of an int.
> 
> well, we have to get prepared for the future world of 128 bit computing.
> coming sooner or later to a computer near you !

Well Moors law demands an additional bit ever 18 month. So PC's will need
128 bit address space in about 24 years. Workstations, Server etc. pp. a
little sooner.

With Regards

Martin

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