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{$MODE OBJFPC}
program test;
type
TBaseClass = class
function PrintSelf(): TBaseClass; inline; // has to be inline for the bug to manifest
end;
TSubClass = class(TBaseClass)
end;
function TBaseClass.PrintSelf(): TBaseClass; inline;
begin
Writeln(PtrUInt(Self));
Result := nil;
Writeln(PtrUInt(Self)); // prints 0!
if not assigned(self) then
halt(1);
end;
procedure NoOp(var Dummy: TBaseClass);
begin
end;
var
Instance, Variable: TBaseClass;
res: longint;
begin
Instance := TSubClass.Create();
Variable := nil;
NoOp(Variable); // this call is important for the bug to manifest
Variable := Instance;
// object being invoked has to be cast to a different type for the bug to manifest
// return value has to be assigned to the variable being used as "self"
Variable := TSubClass(Variable).PrintSelf();
Instance.Free();
end.
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