Re: [RFC] QEMU KVM target -> Anthony

Dâniel Fraga
2007-03-19T00:08:38Z

On Sun, 18 Mar 2007 16:08:21 -0700
"Ed Swierk" <eswierk-t4QvRbHP2kpBDgjK7y7TUQ@public.gmane.org> wrote:

> Please read this email thread if you want to know why your assumption
> is incorrect:
> http://lists.gnu.org/archive/html/qemu-devel/2006-10/msg00175.html

I read everything. The last message by Paul Brook:

"- qemu makes assumptions about the layout of the code gcc generates.
This works by chance on older gcc. This effects all hosts, and is not a gcc bug.

- qemu reserves several registers for its own use. On architecturally crippled
hosts (ie. x86) this means we hit really obscure gcc bugs on x86 because gcc
runs out of registers. This is a gcc bug, but is also relatively easy to
workaround".

He even proposes a solution:

https://nowt.dyndns.org/

And even this way, nobody agreed with each other...

So I ask: if Paul Brook could fix this, why it isn't merged? A
solution should be applied. What we can't do is keep discussing forever
this and the previous message is realy annoying:

"Basically, gcc changed in a way that broke qemu. There's been an open
bug report in gcc ever since, but the GCC developers really aren't interested in
backwards compatability. (Heck, gcc 4.0 breaks building bash 2.05b). The
qemu developers aren't interested in applying ugly patches to support gcc 4.x
until gcc 3.x becomes so obsolete nobody ships it anymore. (And considering
that there are still some niche embedded boards that have hacked up versions
of gcc 2.95 targeting them and nothing else, I wouldn't be surprised if in
five years we have your main compiler and the compiler to build qemu, ala
kgcc under Red Hat 7. *shrug*)"

It's like saying: "we don't care. Keep using gcc3". :(