[Cmake] Ignoring temporary files in AUX_SOURCE

[Amitha Perera]

Hi all

What do you think of a feature to ignore all temporary and backup
files (e.g. emacs's *~ and cvs's .#*) from an AUX_SOURCE scan of
source files? The exact regular expression could be provided as an
argument to AUX_SOURCE, or better, in a variable.

One solution, of course, is to keep the directory clean of temporary
and backup files, but that gets to be painful from time to time.

Amitha.