New comment by tornaria on void-packages repository

https://github.com/void-linux/void-packages/issues/34849#issuecomment-1005125647

Comment:
Indeed:
```
$ rmaxima 
Maxima 5.45.1 https://maxima.sourceforge.io
using Lisp SBCL 2.2.0
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1) :lisp (require :sb-gmp "/usr/lib/sbcl/contrib/sb-gmp.fasl")

(SB-GMP)
(%i1) :lisp (sb-gmp:install-gmp-funs)

(%i1) showtime : true $
Evaluation took 0.0001 seconds (0.0000 elapsed) using 0 bytes.
(%i2) a : 10^(10^5) $
Evaluation took 0.0015 seconds (0.0010 elapsed) using 3.578 KB.
(%i3) b : a^1280 $
Evaluation took 1.5059 seconds (1.5080 elapsed) using 50.689 MB.
(%i4) 
```

Caveats:
 - this only works if `sbcl` is installed (for the file "/usr/lib/sbcl/contrib/sb-gmp.fasl")
 - moreover the version of sbcl used to compile maxima has to match the version of sbcl used to compile `sb-gmp.fasl` (rn maxima was compiled with 2.1.11 but sbcl is at 2.2.0)
 - the "require" statement needs the full path to `sb-gmp.fasl` (not a real problem)