mini-gmp

[paul zimmermann]

       Dear GMP developers,

I see that you have added some functions in the mini-gmp interface, with
respect to the last time I tried it with MPFR, for example mpn_neg, mpn_com
and mpn_sqrtrem. Thanks!

However, we are still missing a proper (documented) way to distinguish
mini-gmp from plain gmp. We could use the __MINI_GMP_H__ macro but it is not
documented. A macro like GMP_IS_MINI would be great, maybe with another
macro that would help us to identify the corresponding version of GMP
(the corresponding plain GMP macro would be GMP_IS_GREAT of course :-)

And I notice that very few of the division functions from mini-gmp correspond
to those of the GMP documentation. Thus to compile MPFR with mini-gmp we had
to re-implement mpn_divrem_1, mpn_divrem and mpn_tdiv_qr. We can contribute
them to mini-gmp if you want.

The other functions we had to re-implement are some random functions
(using srand48/lrand48, thus generating different random sequences, but
for MPFR this is fine), and finally mpz_dump.

Paul