[fpc-pascal] Assigning pointer address

[dhkblaszyk at zeelandnet.nl]

Hi Tomas, 

Thanks for clarifying. I will use PtrUInt to store the
pointer address in. BTW: the documentation it says not to use PtrInt
because it's signed and therefore smaller than a pointer (as in max
value). 

Also there seems to be an error in the documentation. On
http://www.freepascal.org/docs-html/rtl/system/ptruint.html [4] it is
described that PtrUInt is an alias to DWord. However, it depends on the
architecture which type it actually is. Could someone please correct the
docs? 

TIA 

Regards, Darius 

On 1 okt '12, Tomas Hajny wrote: 

> On
Mon, October 1, 2012 10:43, dhkblaszyk at zeelandnet.nl [1]wrote:
> 
>
Hi,
> 
>> I want to ask if casting an integer to a pointer is valid over
all platforms. See below: p: PInteger; v: longint; [...] v := 4235423; p
:= PInteger(v); Of course, the value of the pointer adress may vary, but
in general is this a valid way to assign a pointer? Or will some
platforms or architecture give problems?
> 
> Use PtrInt (signed) or
PtrUInt (unsigned) types instead of longint, etc.
> The former two are
guaranteed to work for all architectures and platforms.
> Your
particular example fails on all 64-bit architectures (among others)
>
immediately.
> 
> Tomas
> 
>
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