[fpc-pascal] Problem with objects

[Santiago Amposta]

Hello:
I use fpc 2.6.4 and I have a problem of memory leaks, strange errors,
etc. Finally I have tracked it to this:

TSimpleArrayString=object
    List:array of String;
end;

TDerivedArrayString=object(TSimpleArrayString)
    other_field:integer;
end;

procedure TestSimple;
var
 A:TSimpleArrayString;
begin
  setLength(A.List,0);
end;

procedure TestDerived;
var
 A:TDerivedArrayString;
begin
  setLength(A.List,0);
end;


TestSimple; // Works Fine,
TestDerived; // rises an exception SIGSEGV on setLength

What am I doing wrong?

-- 
Regards
Santiago A.