Re: 8-byte register values on a 32-bit machine

Paul Koning
2003-03-12T18:48:38Z

>>>>> "Daniel" == Daniel Jacobowitz <drow@mvista.com> writes:

Daniel> On Wed, Mar 12, 2003 at 01:29:03PM -0500, Andrew Cagney
Daniel> wrote:
>> > >The new code fixes some reported wrong-value-reported bugs in
>> other >debugging >situations; one of them was reported just
>> recently. So I don't think >'equalled the functionality of the
>> old mechanism' is really quite fair.
>>
>> True. However, breaking `long long' is a serious regression. If
>> a developer can't trust that, what can they trust?

Daniel> Historically it hasn't been all that trustable anyway. I
Daniel> don't have a testcase handy but CORE_ADDRs in GDB backtraces
Daniel> tend to be wrong, even when they're properly saved to the
Daniel> stack. Et cetera.

I don't like the way this discussion is going. Perhaps I'm reading
too much into the words. A quick review of the thread doesn't help
make it clearer.

We have a large body of code full of long long variables, compiled for
MIPS using the o32 ABI. So each of those ends up in a register pair.

I'm not aware of any reported problems in dealing with long long
variables on that platform.

So... if the current proposal has the side effect of breaking that
working function, on the grounds that it "wasn't all that reliable",
I've got to ask why that's a valid argument.

If that's not the current proposal, could you reword it to help
eliminate the confusion over what you intend?

Thanks,
paul