Subject: Re: Compiler timings on varous MVII NetBSDs etc.
To: Lord Isildur <mrfusion@umbar.vaxpower.org>
From: NetBSD Bob <nbsdbob@weedcon1.cropsci.ncsu.edu>
List: port-vax
Date: 01/25/2001 15:06:07
> > Offhand, can I compile a NetBSD-1.2 kernel on NetBSD-1.5
> > by unrolling into a separate tree, and not break anything?
> 
> i dont know if things would work quite right- config has certainly
> changed betwen 1.3 and 1.4, and probably there some gcc idiosyncracies 
> that will make it barf on the 1.2 stuff.. 

But, I would expect the config from 1.5 to be backwards compatible
with 1.2, but, the reverse, touch and go.

> > My thought would be to compile the identical 1.2 system
> > stripped MVII kernel on the 1.5 box, and see how big it
> > became.  If the kernel was approximately the same size, no
> > problem.  IFF it grew significantly, that might indicate
> > gcc was having problems.  I may have to try that on my M76.
> 
> hmm. it might be worth the effor tin making it work to see directly whats
> from the compiler and whats just the kernel.. :) 

That was exactly my thought.  It does not have to be all that great a
compile, but it just has to finish, and link into a completed kernel.
If there was no great size change, then gcc was doing its job and
a lot of misc gago has not crept in with gcc.  If it grew by
say more than 10%, then gcc is throwing in things, because the
code was the same.

I'm game.... I will unroll a NetBSD-1.2 suite on the M76 box
at home tonight and see if I can make it skip to my lou.

Bob