Horton

Re: [PATCH] Add native windows on arm64 support

Dave Cramer <davecramer@postgres.rocks>

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From: Dave Cramer <davecramer@postgres.rocks>
To: Andres Freund <andres@anarazel.de>
Cc: Andrew Dunstan <andrew@dunslane.net>, Michael Paquier <michael@paquier.xyz>, Anthony Roberts <anthony.roberts@linaro.org>, Daniel Gustafsson <daniel@yesql.se>, Lina Iyer <lina.iyer@linaro.org>, Mike Holmes <mike.holmes@linaro.org>, Peter Eisentraut <peter@eisentraut.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Thomas Munro <thomas.munro@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2024-09-24T20:01:30Z
Lists: pgsql-hackers 
On Tue, 24 Sept 2024 at 14:31, Dave Cramer <davecramer@postgres.rocks>
wrote:

>
>
> On Tue, 13 Feb 2024 at 16:28, Dave Cramer <davecramer@postgres.rocks>
> wrote:
>
>>
>>
>>
>> On Tue, 13 Feb 2024 at 12:52, Andres Freund <andres@anarazel.de> wrote:
>>
>>> Hi,
>>>
>>> On 2024-02-13 12:49:33 -0500, Dave Cramer wrote:
>>> > > I think I might have been on to something - if my human emulation of
>>> a
>>> > > preprocessor isn't wrong, we'd end up with
>>> > >
>>> > > #define S_UNLOCK(lock)  \
>>> > >         do { _ReadWriteBarrier(); (*(lock)) = 0; } while (0)
>>> > >
>>> > > on msvc + arm. And that's entirely insufficient -
>>> _ReadWriteBarrier() just
>>> > > limits *compiler* level reordering, not CPU level reordering.  I
>>> think it's
>>> > > even insufficient on x86[-64], but it's definitely insufficient on
>>> arm.
>>> > >
>>> > In fact ReadWriteBarrier has been deprecated _ReadWriteBarrier |
>>> Microsoft
>>> > Learn
>>> > <
>>> https://learn.microsoft.com/en-us/cpp/intrinsics/readwritebarrier?view=msvc-170
>>> >
>>>
>>> I'd just ignore that, that's just pushing towards more modern stuff
>>> that's
>>> more applicable to C++ than C.
>>>
>>>
>>> > I did try using atomic_thread_fence as per atomic_thread_fence -
>>> > cppreference.com
>>> > <https://en.cppreference.com/w/c/atomic/atomic_thread_fence>
>>>
>>> The semantics of atomic_thread_fence are, uh, very odd.  I'd just use
>>> MemoryBarrier().
>>>
>>> #define S_UNLOCK(lock)  \
>>     do { MemoryBarrier(); (*(lock)) = 0; } while (0)
>>
>> #endif
>>
>> Has no effect.
>>
>> I have no idea if that is what you meant that I should do ?
>>
>> Dave
>>
>
>
> Revisiting this:
>
> Andrew, can you explain the difference between ninja test (which passes)
> and what the build farm does. The buildfarm crashes.
>

I have a dmp file with a stack trace if anyone is interested

Dave

>
> Dave
>