streamlining build process.

[Ben Sapp]

I would like to streamline the Octave build process.  I do not want to
go through the effort of doing it if the changes will not be accepted
though.   

Here is what I would like to do and why.  

1. Make it so that each library is created with one call to ar instead
of one for each .o file.  This is especially advantageous for me because
I run IRIX and the ar man page hast this to say about the best way to
call ar. 
------------------------------------------
Since option -s creates an archive-symbol-table, creating an object
library by executing ar once per object file will be very slow. 
Creating an object library with a single execution of ar is much faster.
-------------------------------------------

2. Make it so that we can run make in parallel.  I believe this will be
almost taken care of by step #1.

I made some modifications to the liboctave Makefile just to see if this
would make things build quicker and here are the results for just
liboctave.  

OS: IRIX
CPU: 2 @ R10000(180Mhz)
MEMORY: 128M
Octave on Local Filesystem
Original Makefile:  18 Minutes 55 seconds
Modified Makefile:  7 Minuts 13 seconds

OS: IRIX
CPU 4 @ R10000(180Mhz)
MEMORY: 384M
Octave on network file system
Original Makefile: 21 Minutes 32 seconds
Modified Makefile: 3 Minutes 50 seconds

OS: Linux
CPU: address@hidden(Intel MMX)
MEMORY: 32M
Octave on local file system
Original Makefile: 28 Minutes 14 seconds
Modified Makefile: 14 Minuts 19 seconds

To be honest I am a bit surprised to see much gain on a 1 CPU Linux
system ...  but I do! :)  Currently it takes ~6-8 hours to build Octave
and an IRIX box.  These changes might cut it to an hour or so.   

So, let me know if these changes would be welcome. (I hope they will
be.)

Thanks.  

-- 
Ben Sapp                         Los Alamos National Laboratory
email: <mailto:address@hidden>   Phone: (505)667-3277
Fax:   (505)665-7920             URL:   http://www.neutrino.lanl.gov/
--