"VV" == Vladimir Volovich writes: VV> the function get_cat_code is called several times, and the first VV> two calls look like: VV> 1) on linux: VV> (gdb) where #0 get_cat_code (h=0, n=88) at actually i was debugging luatex -ini -jobname=luatex -progname=luatex XY thus n=88 Best, v.