[lldb-dev] [Release-testers] [7.0.0 Release] rc1 has been tagged

[Hans Wennborg via lldb-dev]

On Fri, Aug 17, 2018 at 1:27 PM, Dimitry Andric <dimitry at andric.com> wrote:
> On 16 Aug 2018, at 00:51, Joerg Sonnenberger via llvm-dev <llvm-dev at lists.llvm.org> wrote:
>> On Tue, Aug 07, 2018 at 09:49:16PM +0200, Dimitry Andric via llvm-dev wrote:
>>> This is a regression caused by https://reviews.llvm.org/rL323281:
>>>
>>> ------------------------------------------------------------------------
>>> r323281 | wmi | 2018-01-23 23:27:57 +0000 (Tue, 23 Jan 2018) | 12 lines
>>>
>>> Adjust MaxAtomicInlineWidth for i386/i486 targets.
>>>
>>> This is to fix the bug reported in https://bugs.llvm.org/show_bug.cgi?id=34347#c6.
>>> Currently, all  MaxAtomicInlineWidth of x86-32 targets are set to 64. However,
>>> i386 doesn't support any cmpxchg related instructions. i486 only supports cmpxchg.
>>> So in this patch MaxAtomicInlineWidth is reset as follows:
>>> For i386, the MaxAtomicInlineWidth should be 0 because no cmpxchg is supported.
>>> For i486, the MaxAtomicInlineWidth should be 32 because it supports cmpxchg.
>>> For others 32 bits x86 cpu, the MaxAtomicInlineWidth should be 64 because of cmpxchg8b.
>>
>> This seems to be somewhat undesirable. Does *anyone* care about real
>> i386 support at this point? NetBSD certainly doesn't and I think we are
>> already the odd man for a number of cases like this.
>
>
> Yes, and since this causes quite a number of regressions for us, I would
> really prefer this revision to be reverted, at least in the 7.0.0
> branch.  I have already reverted it locally in our FreeBSD project
> branch for importing llvm/clang 7.0.0.  Hans, what is your opinion about
> this?

I'd prefer to see it reverted on trunk, and then merge the revert.

Is there a discussion about reverting started somewhere besides this
thread? It would be nice if we could get this figured out before RC2
(tomorrow, if the schedule holds..)