fpsreadsheet SVN 6891: segfault fix
lazarus / 49-FPSpreadsheet

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vincococka · 2019-05-13 15:01

Dear community,

while using latest fpspreadsheet (SVN commit id: 6891) I encountered
bug while opening Excel8 workbook (xlsbiff8 in fpsreadsheet sources).
It seems to me that the procedure FreeSharedStringTable should look
like this:

procedure TsSpreadBIFF8Reader.FreeSharedStringTable;
var
  j: Integer;
begin
  if not (FSharedStringTable is TStringList) then
    Exit;

  for j := FSharedStringTable.Count-1 downto 0  do
    TObject(FSharedStringTable.Objects[j]).Free;
  FreeAndNil(FSharedStringTable);
end;

Without check "FSharedStringTable is TStringList" it always crashes,
which looks like that FSharedStringTable is not initalized correctly.
Shouldn't FSharedStringTable be initialized in TsSpreadBIFF8Reader
constructor ?

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wp · 2019-05-13 15:45

Please try r6912. Obviously, the check for FSharedStringTable = nil is
missing; it was not needed before r6911 where the method only called
FreeAndNil(FSharedStringTable).

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vincococka · 2019-05-13 16:20

Hi,

thanks for quick fix, reading XLS8 works fine with SVN r6912 .

Greets,
  V.