[XeTeX] segmentation faults in output routine

[Joseph Wright]

On 07/02/2010 01:48, Dohyun Kim wrote:
> On my macbook (snow leopard) I am currently using XeTeX binary shipped
> with tex live 2009 (not MacTeX).
>
> TeX input as follows always crashes xetex in its output routine.
>
> \XeTeXinterchartokenstate=1
> \XeTeXinterchartoks 0   0 {\global\futurelet\lastchar\relax}
> \XeTeXinterchartoks 255 0 {\startcharstring}
> \XeTeXinterchartoks 0 255 {\stopcharstring}
> \def\startcharstring{\XeTeXinterchartoks 255 0 {}}
> \def\stopcharstring {\XeTeXinterchartoks 255 0 {\startcharstring}}
> \pageno=10
> Test.
> \bye
>
> No error message is shown; xetex just crashes:
>
> This is XeTeX, Version 3.1415926-2.2-0.9995.2 (TeX Live 2009)
> entering extended mode
> (./test.texSegmentation fault
>
> Surely, no problem occurs if I define the macro \startcharstring as
> "\XeTeXinterchartoks 255 0 {\relax}".
> But I sometimes have to use empty token list (really empty list even
> without \empty macro) for character mapping.
>
> What I have done wrong? Or is this a bug of xetex engine?
>

See the same here with MacTeX 2009 (Snow Leopard) and with MiKTeX 2.8 
(Windows 7). So I susepct a XeTeX bug.
-- 
Joseph Wright