llvm dev - Dec 2019 - Python 2 compatibility for utility scripts

https://reviews.llvm.org/D71565 intends to update
llvm/utils/update_cc_test_checks.py to work with Python 2.

In the original review, I suggested that we don't add Python 2
compatibility for new features because Python 2.7 is retiring and some
Linux distributions are even deprecating/removing Python 2 support. My
feeling is:

If some utilities do not support Python 2, we should probably not bother
making them Python 2 compatible. Maintaining Python 2/3 compatibility
may not worth the efforts. "utilities" include some command line tools
under llvm/utils, which are not part of instructure like lit. What do
people think?

BTW, what's the Python 3 support status of build bots? Are there any
running Python 3?

On 17/12/2019 06:31, Fangrui Song via llvm-dev wrote:
> 
> BTW, what's the Python 3 support status of build bots? Are there any
> running Python 3?
At least LLDB has some bots running python 3. (lldb+py3+windows combo
has not been working for quite some time now).

pl

I personally only use Python 3 reluctantly. I've yet to encounter a
situation where I actually preferred Python 3. That being said, given the
decision to retire Python 2.7 (*grumble* *grumble*), I'll probably be
forced sometime in the new year to uninstall it by somebody in charge of
security somewhere. I certainly don't see a personal need to have all
scripts support Python 2, unless they are used in the build/test pipeline
somewhere (i.e. get touched by a fresh check-all).

On Tue, 17 Dec 2019 at 05:31, Fangrui Song via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> https://reviews.llvm.org/D71565 intends to update
> llvm/utils/update_cc_test_checks.py to work with Python 2.
>
> In the original review, I suggested that we don't add Python 2
> compatibility for new features because Python 2.7 is retiring and some
> Linux distributions are even deprecating/removing Python 2 support. My
> feeling is:
>
> If some utilities do not support Python 2, we should probably not bother
> making them Python 2 compatible. Maintaining Python 2/3 compatibility
> may not worth the efforts. "utilities" include some command line
tools
> under llvm/utils, which are not part of instructure like lit. What do
> people think?
>
> BTW, what's the Python 3 support status of build bots? Are there any
> running Python 3?
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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At the beginning of the year, I've landed a large set of patches to support
both Python 2 and Python3 in most Python scripts. Looks like I missed some
of them :-)
At that time, backward portability with Python2 was still relevant, and I
suspect it will still be the case for a few distributions that ship Python2
by default. That being said, Even RHEL8 uses Python3 by default, so at some
point we may be able to drop the compatibility stuff.
Until then, I'd argue for maintaining compatibility as it's not a
tremendous task.

On Tue, Dec 17, 2019 at 10:54 AM James Henderson via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> I personally only use Python 3 reluctantly. I've yet to encounter a
> situation where I actually preferred Python 3. That being said, given the
> decision to retire Python 2.7 (*grumble* *grumble*), I'll probably be
> forced sometime in the new year to uninstall it by somebody in charge of
> security somewhere. I certainly don't see a personal need to have all
> scripts support Python 2, unless they are used in the build/test pipeline
> somewhere (i.e. get touched by a fresh check-all).
>
> On Tue, 17 Dec 2019 at 05:31, Fangrui Song via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> https://reviews.llvm.org/D71565 intends to update
>> llvm/utils/update_cc_test_checks.py to work with Python 2.
>>
>> In the original review, I suggested that we don't add Python 2
>> compatibility for new features because Python 2.7 is retiring and some
>> Linux distributions are even deprecating/removing Python 2 support. My
>> feeling is:
>>
>> If some utilities do not support Python 2, we should probably not
bother
>> making them Python 2 compatible. Maintaining Python 2/3 compatibility
>> may not worth the efforts. "utilities" include some command
line tools
>> under llvm/utils, which are not part of instructure like lit. What do
>> people think?
>>
>> BTW, what's the Python 3 support status of build bots? Are there
any
>> running Python 3?
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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