> > > I probably need to upgrade, as I have found no mention of
> > > am_missing_run on the files owned by my current autoconf package,
> > > whereas it is defined in m4/missing.m4 in autoconf 2.52.
> >
> > I can't say as I found it in any documentation. I pulled it out of
> > other examples of its use in /usr/share/{aclocal,autoconf,automake}!
> > It might not be a public interface!
>
> Can't tell. What surprises me is that I haven't found it anywhere in the
> files of my 2.13 binary package, but still autoconf doesn't complain about
> it when it sees it :).
That's because it's a shell variable, not a macro.
What's more, it's a shell variable set by _automake_, not autoconf.
You'll need to call
AC_CHECK_PROGS(YACC, byacc yacc 'bison -y', [AM_MISSING_PROG(yacc)])
instead of using the undocumented, unsupported, internal am_missing_run
variable. Then run aclocal to pull in the macro definitions needed.
Note that this _may_ require a recent automake (1.5 recommended).
