[PATCH] GDB: Prefer Python 3 over 2

[Chris Johns]

On 21/3/2022 5:54 pm, Sebastian Huber wrote:
> On 20/03/2022 23:22, Chris Johns wrote:
>> On 19/3/2022 8:33 pm, Sebastian Huber wrote:
>>> On 18/03/2022 22:56, Chris Johns wrote:
>>>>
>>>>> On 19 Mar 2022, at 2:40 am, Sebastian Huber
>>>>> <sebastian.huber at embedded-brains.de> wrote:
>>>>>
>>>>> On 17/03/2022 12:51, Sebastian Huber wrote:
>>>>>> This fixes the build of a recent GDB version:
>>>>>> gdb/python/py-micmd.c: In function 'int
>>>>>> micmdpy_uninstall_command(micmdpy_object*)':
>>>>>> gdb/python/py-micmd.c:430:20: error: 'PyDict_GetItemWithError' was not
>>>>>> declared in this scope
>>>>>>      PyObject *curr = PyDict_GetItemWithError (mi_cmd_dict.get (),
>>>>>>                       ^~~~~~~~~~~~~~~~~~~~~~~
>>>>
>>>> Has a bug report been raised with gdb?
>>>
>>> The Python 2 EOL was January 1, 2020. This code was added by:
>>>
>>> commit 740b42ceb7c7ae7b5343183782973576a93bc7b3
>>> Author: Andrew Burgess <aburgess at redhat.com>
>>> Date:   Tue Jun 23 14:45:38 2020 +0100
>>>
>>>      gdb/python/mi: create MI commands using python
>>>
>>> It is not a bug from my point of view.
>>
>> The change has been reviewed again ...
>>
>> commit 5ec0444e8312c17e628739ebd7b8f0e29df3c9e9
>> Author: Andrew Burgess <aburgess at redhat.com>
>> Date:   Fri Mar 18 15:55:34 2022 +0000
>>
>>      gdb: supply PyDict_GetItemWithError when compiling with Python2
> 
> Good timing.
> 
> I still think the patch to prefer the Python 3 installation of the Python 2
> installation makes sense. We will have this issue again if I want to build the
> GDB main branch some time in the future.

Yeah I think this is sensible. If we can still build python2 then I am OK with
this change.

>>>>> I was able to build the latest GDB with this patch. Otherwise all
>>>>> architectures failed with the above error.
>>>>
>>>> Has gdb dropped Python 2 support?
>>>
>>> It seems so.
>>
>> It seems from above is after gdb 12 has branched. We could settle on gdb 12 for
>> rtems6?
> 
> Given that GDB 12 isn't released yet this doesn't sound like a constraint.
> 

Great. We need to get the tools back to released source for the rtems6 release
so we should track this and then switch.

>>>> What happens on a host without python3 installed? Does the error appear? Does
>>>> this in effect force RTEMS to drop the Python2 requirement for rtems6?
>>>
>>> I guess if we want to use the next GDB release, then Python 3 is required.
>>>
>>
>> Then this changes rtems6 because it forces a major change I had not expected on
>> to rtems6. I suggest a separate thread be started to again consider removing
>> python 2 support for rtems6. It do not bother me but we have some users where is
>> may so it is best to ask openly.
> 
> Yes, this makes sense.

Great

Chris