Re: RFC: New approach to --with-cpu

[Daniel Jacobowitz <drow@mvista.com>]

On Tue, Jul 30, 2002 at 09:31:41PM -0400, John David Anglin wrote:
> >From a PA standpoint, the main objection that I have to this approach
> is that there seems to be a slight loss of flexibility.  You use "with_cpu"
> to set the default scheduling model.  However, I was also planning to set
> the default arch based on the target machine when a linker bug in handling
> PA2.0 code is fixed.  I view these options as independent although the
> configure defaults would both be based on the target triplet.  Thus,
> it would be necessary to introduce a new configure option to handle
> the arch default.  In the future, I can see other default code generation
> options being set-table.

Well, that's no problem.  A first cut of this patch offered defaults
for -march= and -mtune= separately on MIPS.  I could do the same for
PA easily.

> I must admit that I don't really like the multilib concept and find
> it a rather  idea to build libraries for all scheduling models,
> archs, etc.  Thus, I don't find this justification attractive.

I don't like multilibs either.  Eric mentioned some concerns that this
would interfere with them when I discussed it with him, which is why I
brought it up.

The real advantage of my approach is getting anything specs-based
correct.  For instance, the preprocessor flags related to -msoft-float
are set correctly if you use --with-float=soft.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer