how to install libdecnumber?

[David P. Riedel]

I have built gcc 4.8 into a separate location on my Arch Linux system.

Here are my configuration settings.

/extra/gcc/gcc-4.8/bin/gcc -v
Using built-in specs.
COLLECT_GCC=/extra/gcc/gcc-4.8/bin/gcc
COLLECT_LTO_WRAPPER=/extra/gcc/gcc-4.8/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-4.8.0/configure --prefix=/extra/gcc/gcc-4.8 
--enable-shared --enable-libstdcxx-debug --enable-threads 
--enable-clocale=gnu --enable-decimal-float --enable-__cxa_atexit 
--with-system-zlib --disable-multilib --enable-languages=c,c++ 
--enable-cloog-backend=isl --with-host-libstdcxx=-lstdc++ --enable-lto 
--enable-gold
Thread model: posix
gcc version 4.8.0 (GCC)

I would like to use libdecnumber but it is nowhere to be found in my 
installed directory hierarchy.  When I look in my build directory I find 
libdecnumber/libdecnumber.a so it seems it built OK but neither the 
library file nor any of the headers from gcc-4.8.0/libdecnumber are in 
the installed gcc directory hierarchy.

If I go to the libdecnumber directory in my build directory and run 
'make install', it just says there is nothing to do.

Am I missing something?

What is the proper way to build and install libdecnumber for gcc 4.8?

Thanks for your help.

Dave Riedel