MemCheck tutorial: find bad calls

1. In MemCheck, set DeallocateFreedMemoryWhenBlockBiggerThan to a reasonnable value, eg MaxInt (this value is not reasonnable if your program allocates very big spaces, eg big vectors - then choose for example 1000)
2. In MemCheck set WipeOutMemoryOnFreeMem to true
3. Define a class TMyObject
       TMyObject = class
           procedure p; virtual;
           end;
4. Define TMyObject with an empty body
5. Add a procedure BadCall
       procedure BadCall;
           var
       t: TMyObject;
           begin
       t:= TMyObject.Create;
       t.Destroy;
       t.p;
           end;
6. In the dpr's body, just call BadCall
       begin
           MemChk;
           BadCall;
       end.
7. When you run the program, MemCheck will tell you you are calling P after the object has been destroyed. Better than an access violation, no ? And this is very useful for double destructions.

Last update: March 2001