When a configure.ac or configure.in file is opened new in an Autotools project,
if the first lines are comments (e.g. dnl abcd or # abcdef), editing the last
line causes characters to appear in reverse order. An exception may occur
trying to delete these characters.
The problem existed in a custom editor rule added by Autotools that was not
properly checking for EOF in the scanner. A fix has been made so this problem
does not occur. A temporary workaround to the problem is to add a blank line at
the top of the new file. This problem does not occur for existing configure files.