[PATCH] Disable use of std::call_once on OpenBSD with libstdc++

[Brad Smith via llvm-commits]

On 10/23/16 20:58, Brad Smith wrote:
> On Sun, Oct 23, 2016 at 10:15:37PM +0200, Joerg Sonnenberger via llvm-commits wrote:
>> On Sat, Oct 15, 2016 at 04:46:19PM -0400, Brad Smith via llvm-commits wrote:
>>> Disable the use of std::call_once on OpenBSD with libstc++. It was noticed this caused
>>> performance regressions and deadlocks.
>>
>> I'd prefer to reorder this somewhat to make it clear what is tested:
>>
>> LLVM_ON_UNIX && (LIBCPP_VERSION || !(NetBSD || OpenBSD || ppc)).
>>
>> and invert the comment accordingly, e.g. "std::call_once from libc++ is
>> used on all Unix platforms. Other implementations like libstdc++ are
>> known to have problems on NetBSD, OpenBSD and PowerPC."
>>
>> This is a change on PPC, but it seems to match the intention.
>
> An updated patch is attached.
>
> I created a PR as requested, PR30768.

Any further comment? LGTM?