>>>> "Stephen" == Stephen J Turnbull
<stephen(a)xemacs.org> writes: 
    Stephen> Try it in the debugger, put it in that state, and see where it's
hung?
    Stephen> For Ray, crashing under the debugger ought to get a plausible trace; I
    Stephen> suspect you're not really in zero_out_command_line_status_vars ().
A little more info:  gdb says:
Fatal error: assertion failed, file /apps/public/XEmacs/src/xemacs-21.5.6/src/alloc.c,
line 1861, i == (Bytecount) XSTRING_ASCII_BEGIN (str) || (i > MAX_STRING_ASCII_BEGIN
&& (Bytecount) XSTRING_ASCII_BEGIN (str) == (Bytecount) MAX_STRING_ASCII_BEGIN)
But the backtrace ends on zero_out_command_line_status_vars.  I guess
the bug is trashing the stack as well.
Ray