On Mon, Jun 27, 2011 at 02:32:26PM -0700, Yasha Karant wrote:
> 
> 1.  How to install the SL6 release so that the System ->
> Administration -> Add/Remove Software will list both the 64 bit and
> 32 bit libraries? ...
>
> 2.  Many packages that must be built from source rely upon configure
> and for various reasons, paths such as /usr/lib , not /usr/lib64
> that is the X86-64 path, appear. ...
>


At TRIUMF we have the need to cross-compile 32-bit executables on 64-bit machines.

This is for two reasons: we have some dedicated hardware that only
runs 32-bit executables (VME processors, etc) but is too slow and
does not have enough memory to support a self-hosting build
environement (so we have to cross-compile); and we have some software
that uses 32-bit-only 3rd party proprietary libraries.

So I am very familiar with the questions you asked, but only for SL5. We are
just starting to use SL6, but so far everything seems to be the same.

1) "out of the box", "yum list" shows both 32-bit and 64-bit packages. (From SL5
to SL6, 32-bit packages changed from .i386 to .i686 and tripped up some
sysinstall scripts).

Not all existing 32-bit packages are included into the 64-bit distribution. To install
them, you can add the 32-bit repo to your system (but be ready to handle conflicts!)

Some 32-bit packages will conflict with same-named 64-bit packages, if really
required, one can force their installation by using "rpm -vh --install --no-deps" (but
if you break your system, you get to keep both pieces).

Some 32-bit packages are throughfully supplied through the "compat" packages.

If not, move to question 2:

2) yes, very often building of external packages from source becomes
confused by /usr/lib & /usr/lib64 & etc. This is where autotools becomes
a bother instead of helper. Things like "pkg-config", "foo-config" also
work against us as they are broken by design for the case when 32-bit
or 64-bit libraries need to be selected as needed.

The general trend seems to be towards "things only work on
the developer's laptop" and if stuff does not work for you it is because
"your machine is different from my laptop" and tough luck with it.


-- 
Konstantin Olchanski
Data Acquisition Systems: The Bytes Must Flow!
Email: olchansk-at-triumf-dot-ca
Snail mail: 4004 Wesbrook Mall, TRIUMF, Vancouver, B.C., V6T 2A3, Canada