*UNCLASSIFIED* One more - this time with full debugging symbols and bt full log attached :) I'll try and keep the gdb session alive for a while if you need anything further Program received signal SIGSEGV, Segmentation fault. 0x00000000006863ea in composition_compute_stop_pos (cmp_it=0x7fffffff9058, charpos=101, bytepos=118, endpos=116, string=32972417) at composite.c:1073 1073 elt = XCAR (val); (gdb) p string $1 = 32972417 (gdb) xtype Lisp_String (gdb) xstring $2 = (struct Lisp_String *) 0x1f71e80 " Arglist: (X)", ' ' IMPORTANT: This email remains the property of the Department of Defence and is subject to the jurisdiction of section 70 of the Crimes Act 1914. If you have received this email in error, you are requested to contact the sender and delete the email.