[fpc-pascal] question on pointers

[Florian Klaempfl]

Adriaan van Os wrote:

> dhkblaszyk at zeelandnet.nl wrote:
> 
>> I have a question on copying data to a pointer array. I'm not that into
>> pointers, so I can't figure out what I'm missing here. I have included
>> sample code below, and I get a SF on the line where I assign the data to
>> the pointer.
>> Is it perhaps that I need to assign memory to the pointer data??
>>
>> Darius
>>
>> procedure TForm1.Button1Click(Sender: TObject);
>> type
>>   myfloat = extended;
>>   pmyfloat = ^myfloat;
>>
>> var
>>   test: array of pmyfloat;
>>   test2: array of myfloat;
>> begin
>>   setlength(test, 1);
>>
>>   setlength(test2, 1);
>>   test2[0] := 3.141;
>>
>>   test[0]^ := test2[0];
> 
> 
> test[0]:=@test2[0];
> 
> I suggest you read a tutorial on pointers. They can be very dangerous,
> so you should know what you are doing.

Even worse when combining them with dyn. arrays. As soon as you do a
setlength(test,x); all previous references to elements of test might be
invalid.