NOTE: installation uses automake/autoconf as used in rheolef.
Here is the text of the original INSTALL file.
january 1999, Pierre.Saramito@imag.fr
------------------------------------------------------------
Installation of doubledouble:

0. Unpack shar or tar file.
   Typical location: ~/math++/2.2/

1. Edit top part of `Makefile' to suit your hardware and compiler

2. make

User programs should:

   (a) #include "doubledouble.h"
   (b) compile with -DDD_INLINE
   (c) compile with -Dx86 on x86 hardware (including Pentium)
   (d) link libdoubledouble.a

See trydd.cc for examples of usage.

This code has been tested on:
x86-unknown-linux with gcc 2.7.2.1 
mips*-sgi-irix6 with ecgs-1.0
sparc-sun-solaris2.4 with ecgs-1.0
x86-windows95 with Microsoft C++ 5.0

Please report problems (or success!) to Keith Briggs kmb28@cam.ac.uk.

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# linux-x86, special KMB setup...
#CXX=g++-old
#OPTS=-m486 -O3 -Wall
#INC=-I/usr/include/g++ -I/usr/lib/gcc-lib/i386-linux/2.7.2.1/include/
#DEF=-DDD_INLINE -Dx86
#RANLIB=ranlib

# mips-sgi-irix with CC...
#CXX=CC
#OPTS=-O
#INC=
#DEF=-DDD_INLINE -DSGI_CC
#RANLIB=ls # nop

# mips-sgi-irix with egcs...
#CXX=g++ # this must be g++ >=2.8, or better egcs-1.0
#OPTS=-O
#INC=
#DEF=-DDD_INLINE
#RANLIB=ls # nop

