Install Math::GMP

[Franck MICHEL]

>Yep, I guess so.  You'll need that of course.  Make sure hello world
>works in 64-bit mode before worrying about gmp.

The installation of gcc seems to be ok: libgcc_s.so.1 is available in
64-bit in /usr/local/lib/sparcv9

>LD_LIBRARY_PATH is a known cause of trouble on v9 solaris, since it
>overrides the 64-bit search path as well as the 32.

Thank you for this indication.
I have unset LD_LIBRARY_PATH, set LD_RUN_PATH, and run the default
installation of GMP. All seems to work fine now. The performance is far
better in 64 bit than in 32 bit.

Cheers,

  Franck