[W528] False positive when using for.. in

The following section of code results in a false positive W528 "Variable 'StopChar' not used in FOR-loop". This is not a complete and tried example, just an extract from the routine.

FixInsight 2015.10.

TempIndex := NewLineIndex;
for StopChar in StopChars do
    if Self.FBufferedData[TempIndex] <> StopChar then
        Break
    else
        Inc(TempIndex);