Указатель на вариантный тип

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I just ran across this in some of my old code and thought I''d share it with you:

Consider the following (simplified code):

Code:

function CreateVariantPtr(_Value: variant): pVariant;

begin

GetMem(Result, SizeOf(Variant));

Result^ := _Value;

end;

Seems pretty simple, doesn''t it? Anybody who can spot the bug? I got spurious access violations in the line Result^ := _Value; Ok, the reason: Memory allocated with GetMem is not initialised, so the "Variant" pointed to by Result contains some random data, for example something that might represent a variant type which requires some finalisation when the variant is changed, lets say a variant array of some sort. But this finalisation won''t work because the content is just some random garbage, and sometimes I was lucky (I mean that!) and got an access violation that allowed me to spot the error. The fix:

Code:

function CreateVariantPtr(_Value: variant): pVariant;

begin

GetMem(Result, SizeOf(Variant));

Initialize(Result^);

Result^ := _Value;

end;

©Drkb::00833

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