Hello,

Please add support for this architecture, simple patch attached (based
on guile-2.0, the most popular version in Debian).

The change is simply to add "riscv64" in the following location, the
arch name seems to be missing in:

  http://git.savannah.gnu.org/cgit/guile.git/tree/module/system/base/target.scm#n74

Since it ends in -64, the pointer size should be detected correctly in
the current code.

I compiled this and ran the test suite successfully:

Totals for this test run:
passes:                 40317
failures:               0
unexpected passes:      0
expected failures:      9
unresolved test cases:  571
untested test cases:    1
unsupported test cases: 10
errors:                 0

If there's anything missing, please let me know.


Cheers.
-- 
Manuel A. Fernandez Montecelo <manuel.montezelo@gmail.com>