Replacement for GMP as Bignum: ARPREC? Haskell?; OS-X and OpenSSL

p.tanski at p.tanski at
Sat Jul 29 21:45:21 EDT 2006

GHC Task Ticket # 601 suggests replacing GMP with OpenSSL's Bignum library, BN.
I have two questions concerning this:

(1) Why not use the ARbitrary PRECision Computation Package (ARPREC)
by David Bailey, Yozo Hida, Karthik Jeyabalan, Xiaoye Li and Brandon
Thompson?  Here is a reference web page:

ARPREC is written in C++ but supports calls from C (see
include/arprec/c_mp.h in the distribution directory).  ARPREC is very
fast and supports more complex mathematics than BN.  The Licensing for
ARPREC is not a problem: essentially similar to BSD3.

Note that there would be a basic configuration fix for building
OpenSSL's BN library on OS 10.4: you would probably--I had to,
myself--have to temporarily move the default installation of
/usr/lib/libssl0.9.dylib (and variants) if you want to create a shared
(.a) library because Apple's ln links dynamic libraries in preference
to shared libraries.  Those of you who have some experience with
Apple's gcc also know that Apple's gcc does not recognise the -shared

(2) A much more aesthetic solution would be to replace any external
Bignum library with a pure Haskell library.  There are many problems
with building a truly efficient and fast Bignum library in Haskell but
challenges like that are how languages evolve...

-Peter Tanski

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