[Lazarus] Weird object variables access [SOLVED] - Delphi mode bug!

Michael Van Canneyt michael at freepascal.org
Wed Oct 25 11:14:22 CEST 2017

On Wed, 25 Oct 2017, Ondrej Pokorny via Lazarus wrote:

> On 24.10.2017 23:18, Michael Van Canneyt via Lazarus wrote:
>> On Tue, 24 Oct 2017, Giuliano Colla wrote:
>>> Il 24/10/2017 14:10, Michael Van Canneyt via Lazarus ha scritto:
>>>> A valid method can never be stored in a pointer, since the former is 
>>>> actually 2 pointers (method/data) and the latter is just 1 pointer.
>>>> That the assignment is valid is Delphi compatible: only the procedure
>>>> address is copied. 
>>> I can confirm it as an fpc bug.
>> No, I'm sorry to say that IMO you did not. I looked at your code.
>> It simply works by accident in Delphi, because you are calling a method of 
>> the same object as the caller.
> Yes, the code is wrong. But the reason is that myMethod is assigned in 
> FormCreate. The later "@myMethod := pMethod;" assignment overwrites only half 
> of the myMethod:TProc variable and so correct Self stays in the second half 
> of myMethod.

That is what I wanted to indicate :)


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