Re: A completely different approach to EH runtime

["H . J . Lu" <hjl at valinux dot com>]

On Wed, Feb 21, 2001 at 11:29:38AM -0800, Zack Weinberg wrote:

> with no explanation.  We have no way of evaluating your assertion that
> "the current scheme is a huge problem for Linux."  All we know is that
> you say it's a problem.  Lots of the GCC developers don't concern
> themselves with EH runtime issues at all.  Those of us who know about
> the EH runtime, are not also system integrators.  So we don't have any
> context.

Then, how about starting with "don't assume there is no problem for
Linux"? How about actively seeking feedback/approval from the glibc
people instead of throwing it at glibc?

> 
> You need to describe in excruciating detail exactly what will break,
> and why.  It is not at all obvious to us why it is a huge problem.
> Convince us.
> 
> Oh, and "I don't trust you not to break the ABI in a future release"
> will be read as an insult, so don't even bring it up.  Assume we're
> competent.

I guess if you were never in a position that your DSO is used
everywhere, you might not understand all the issues involved.

Just think about you have more than libc.so.6 on your Linux machine in
different direcories and they are both visibible to ld-linux.so.2. Can
you tell me what may happen?

Also how safe for Linux people to install gcc 3.0 with shared libgcc?
Do you know if it is safe for random Linux people to build/upgrade
their glibc? Right now we tell Linux people if you don't know what you
doing, don't build/upgrade glibc yourselves. Get it from your Linux
distribution. That is because glibc is a system software. Can we tell
the same line to Linux people who want to try new gcc?

Also how do you safely install something is being used by all other
running processses on your machine?

There are so many issueses involved. I may have missed something. The
point is we, the glibc people, have gone through it. We know it is a
very sensitive problem for Linux.

Making libgcc shared also makes libgcc a system software. Before that,
installing gcc is not much different from other 3rd party softwares. It
may not be a problem for platforms where gcc is not the native system
compiler. But it is not the case for Linux. We have to be very careful.


-- 
H.J. Lu (hjl@valinux.com)