[fpc-devel] TObjectList crash!

[Michael Van Canneyt]

On Tue, 9 Sep 2008, Paul Ishenin wrote:

> Hello,  FPC developers' list.
> 
> We are preparing a next lazarus version and our users are heavily testing
> thing. One bug report let me found one error which is not a lazarus error, but
> fpc. This error happen because we used TObjectList to store bitmaps in a list.
> 
> TObjectList is a useful thing - we dont need to think about object destroying.
> They will be destroyed on deleting from the list. And everyting works except
> next call: AList[AIndex] := NewObject
> 
> I attached a test projects which shows a bug.
> 
> But in few words this bug happen due to double object destroying:
> 1. In TObjectList.SetItem (this is *not correct* place to destroy)
> 2. In TObjectList.Notify (this is *correct* place to destroy)
> 
> A solution is simple: remove everything from TObjectList.SetItem except Put
> call.

Confirmed, patched as suggested and tested. Revision 11732.
Merged to fixes in rev. 11733.

Michael.