Outdated libtool creates trouble on macOS

[Torbjörn Granlund]

Marc Glisse <marc.glisse at inria.fr> writes:

  It looks recent enough that the piece of code causing trouble on macOS
  has been modified. I think we can go with that, we can always upgrade
  again later if needed.

We have been using the default shell.gmplib.org autotools tools for a
week now, for generating the public snapshots and the nightbuild
snapshots.  Things look good.

Thanks for this GMP contribution!

-- 
Torbjörn
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