Re: AC_FLAGS_WARN_ALL changes proposed for inclusion in next autoconf release

Thanks for getting the ball rolling on this.  A couple of thoughts.

First, how does this compare to the warnings and manywarnings modules of 
Gnulib?  They seem to do something similar.  See:

http://www.gnu.org/software/gnulib/manual/html_node/warnings.html

http://www.gnu.org/software/gnulib/manual/html_node/manywarnings.html

Second, from a brief look at the patch it appears that it is derived 
from code that other people have written, which would mean we'd need to 
get copyright papers from them too.