GMP 6.0.0a on AMD A8-6600K

[Kevin Buckley]

On 9 April 2015 at 22:12,  <tg at gmplib.org> wrote:

> I've lost track, did you try a GMP snapshot in a Xen guest?

Not in a domU, no.

When I saw that the Xen host (dom0) - itself a kind of "Xen guest"
as I think of it - was exhibiting the problems, I stopped.

My assumption there was that if Xen wasn't passing opcodes through
to the dom0, then it wasn't going to pass them through to any domU.

> Did you try Niels' suggested gdb commands on a failing system?

Not yet.

> Another way which might be easier is to re-configire with --disable-shared, then build,
> then do
>
>   $ gdb some-problem-testcase
>   (gdb) run
>   [expect illop]
>   (gdb) x/5i
>   (gdb) bt
>
> This will show us the "illegal" instruction and the call chain which
> took us there.
>
> The goal of this exercise is to (1) properly understand the problem, and
> (2) to make sure we've fixed it.

Will certainly give that a go.

It'll probably be the weekend before I get to add more info into the mix
for you, though.