BSD m4 (was: more m4 underquotations)

[Bruno Haible]

Eric Blake wrote:
> One more misfeature of changequote - changequote(,) is not
> portable.  The BSD folks have been trying to get their m4
> implementation to copy enough of GNU m4's traits that it
> can be used in place of GNU M4 to support autoconf.

But we don't need to care about that. We aren't putting clever features into
our tools, just to later fall back to the least common denominator. We have
been telling people that they need GNU m4 for autoconf and automake for years -
there is no reason to stop doing so.

> I DO know that in the
> current source code of BSD m4, "changequote(,)" behaves
> like "changequote" (ie. sets the quotes to ` and ') rather than
> the GNU behavior of disabling quotes.

This sounds like a POSIX [1] violation of BSD m4.

Bruno


[1] http://www.opengroup.org/susv3xcu/m4.html