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Re: [RFC] Add dummy toplevel configure.ac
> Instead, how about something like this in the existing configure.in?
>
> AC_PREREQ(2.13)
> dnl ... and _not_ any later version. It is too much work to test the
> dnl actual version number, which is hidden in a macro whose name
> dnl changes repeatedly in the releases between 2.13 and current.
> dnl However, there's a simpler test: the m4_ macros exist only in
> dnl 2.50 and above.
> ifdef([m4_ifdef],
> [AC_FATAL([toplevel configure should be created using autoconf 2.13])
> ])dnl
>
> AC_FATAL is available in autoconf 2.50 (yes, I downloaded the old
> release tarball and checked) so this should work with any version.
> [Well, I'm not sure if versions exist that don't provide 'ifdef'
> at all, only 'm4_ifdef', but there we're just plain screwed - how
> can you query the existence of the very primitive one uses to query
> existence?]
How about using AC_MSG_ERROR, which has been available practically
forever?
Ben