Re: [PATCH v1 08/13] aarch64: Add Cygwin and MinGW environments for AArch64

[Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>]

> On Feb 29, 2024, at 21:59, Richard Earnshaw (lists) <Richard.Earnshaw@arm.com> wrote:
> 
> On 29/02/2024 17:55, Andrew Pinski (QUIC) wrote:
>>> -----Original Message-----
>>> From: Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>
>>> Sent: Thursday, February 29, 2024 9:46 AM
>>> To: Andrew Pinski (QUIC) <quic_apinski@quicinc.com>
>>> Cc: Evgeny Karpov <Evgeny.Karpov@microsoft.com>; Andrew Pinski
>>> <pinskia@gmail.com>; Richard Sandiford <richard.sandiford@arm.com>; gcc-
>>> patches@gcc.gnu.org; 10walls@gmail.com; mark@harmstone.com; Zac
>>> Walker <zacwalker@microsoft.com>; Ron Riddle
>>> <Ron.Riddle@microsoft.com>; Radek Barton <radek.barton@microsoft.com>
>>> Subject: Re: [PATCH v1 08/13] aarch64: Add Cygwin and MinGW
>>> environments for AArch64
>>> 
>>> WARNING: This email originated from outside of Qualcomm. Please be wary
>>> of any links or attachments, and do not enable macros.
>>> 
>>>> On Feb 29, 2024, at 21:35, Andrew Pinski (QUIC)
>>> <quic_apinski@quicinc.com> wrote:
>>>> 
>>>> 
>>>> 
>>>>> -----Original Message-----
>>>>> From: Evgeny Karpov <Evgeny.Karpov@microsoft.com>
>>>>> Sent: Thursday, February 29, 2024 8:46 AM
>>>>> To: Andrew Pinski <pinskia@gmail.com>
>>>>> Cc: Richard Sandiford <richard.sandiford@arm.com>; gcc-
>>>>> patches@gcc.gnu.org; 10walls@gmail.com; Maxim Kuvyrkov
>>>>> <maxim.kuvyrkov@linaro.org>; mark@harmstone.com; Zac Walker
>>>>> <zacwalker@microsoft.com>; Ron Riddle <Ron.Riddle@microsoft.com>;
>>>>> Radek Barton <radek.barton@microsoft.com>; Andrew Pinski (QUIC)
>>>>> <quic_apinski@quicinc.com>
>>>>> Subject: [PATCH v1 08/13] aarch64: Add Cygwin and MinGW environments
>>>>> for AArch64
>>>>> 
>>>>> Wednesday, February 28, 2024 2:00 AM
>>>>> Andrew Pinski wrote:
>>>>> 
>>>>>> What does this mean with respect to C++ exceptions? Or you using
>>>>>> SJLJ exceptions support or the dwarf unwinding ones without SEH
>>> support?
>>>>>> I am not sure if SJLJ exceptions is well tested any more in GCC either.
>>>>>> 
>>>>>> Also I have a question if you ran the full GCC/G++ testsuites and
>>>>>> what were the results?
>>>>>> If you did run it, did you use a cross compiler or the native
>>>>>> compiler? Did you do a bootstrap (GCC uses C++ but no exceptions
>>> though)?
>>>>> 
>>>>> As mentioned in the cover letter and the thread, the current
>>>>> contribution covers only the C scope.
>>>>> Exception handling is fully disabled for now.
>>>>> There is an experimental build with C++ and SEH, however, it is not
>>>>> included in the plan for the current contribution.
>>>>> 
>>>>> https://github.com/Windows-on-ARM-Experiments/mingw-woarm64-
>>> build
>>>>> 
>>>>>> If you run using a cross compiler, did you use ssh or some other
>>>>>> route to run the applications?
>>>>>> 
>>>>>> Thanks,
>>>>>> Andrew Pinski
>>>>> 
>>>>> GitHub Actions are used to cross-compile toolchains, packages and
>>>>> tests, and execute tests on Windows Arm64.
>>>> 
>>>> This does not answer my question because what you are running is just
>>> simple testcases and not the FULL GCC testsuite.
>>>> So again have you ran the GCC testsuite and do you have a dejagnu board to
>>> be able to execute the binaries?
>>>> I think without the GCC testsuite ran to find all of the known failures, you are
>>> going to be running into many issues.
>>>> The GCC testsuite includes many tests for ABI corner cases and many
>>> features that you will most likely not think about testing using your simple
>>> testcases.
>>>> In fact I suspect there will be some of the aarch64 testcases which will need
>>> to be modified for the windows ABI which you have not done yet.
>>> 
>>> Hi Andrew,
>>> 
>>> We (Linaro) have a prototype CI loop setup for testing aarch64-w64-
>>> mingw32, and we have results for gcc-c and libatomic -- see [1].
>>> 
>>> The results are far from clean, but that's expected.  This patch series aims at
>>> enabling C hello-world only, and subsequent patch series will improve the
>>> state of the port.
>>> 
>>> [1] https://ci.linaro.org/job/tcwg_gnu_mingw_check_gcc--master-woa64-
>>> build/6/artifact/artifacts/sumfiles/
>> 
>> Looking at these results, this port is not in any shape or form to be upstreamed right now. Even simple -g will cause failures.
>> Note we don't need a clean testsuite run but the patch series is not even allowing enabling hello world due to the -g not being able to used.
>> 
> 
> It seemed to me as though the patch was posted for comments, not for immediate inclusion.  I agree this isn't ready for committing yet, but neither should the submitters wait until it's perfect before posting it.
> 
> I think it's gcc-15 material, so now is about the right time to be thinking about it.

Hi Andrew,

I agree with Richard.  This patch series is large as is, and it has clear goals:
1. Enable aarch64-w64-mingw32 to compile C-language hello-world.
2. Not regress any other targets.

As far as I know, it achieves both, but both Microsoft and Linaro will do additional testing on x86_64-w64-mingw32 to confirm.

There are more features and fixes for aarch64-w64-mingw32 waiting in the development repos on github, but I don't see any point in cleaning them up and preparing for submission before this already-quiet-large patchset if reviewed.

Thank you,

--
Maxim Kuvyrkov
https://www.linaro.org