Re: pahole: Fix deprecated cmake_minimum_required

Re: pahole: Fix deprecated cmake_minimum_required

[Arnaldo Carvalho de Melo]

On Tue, Oct 28, 2025 at 07:58:17AM +0100, Matthias Schwarzott wrote:
> I got to know that using a cmake_minimum_required version of less than 3.10
> is deprecated. Support for it will be removed from cmake.

Support for what? For features present before 3.10? So we better make
sure that we have pahole use that 'cmake_minimum_required(3.10)' so that
we don't end up using such deprecated cmake features and end up breaking
the build in distros using, say, cmake 3.11?

Please CC dwarves@vger.kernel.org when sending patches, like I did in
this reply :-)

Thanks!

- Arnaldo
 
> I suggest to raise the minimum required cmake version to at least 3.10
> (released 20 November 2017).
> See attached patch.

> see gentoo pahole issue: https://bugs.gentoo.org/964482
> gentoo overall issue: https://bugs.gentoo.org/964405
 
> cmake merge request:
> https://gitlab.kitware.com/cmake/cmake/-/merge_requests/9875
 
> deprecate-pre-3.10
> ------------------
 
> * Compatibility with versions of CMake older than 3.10 is now deprecated
>   and will be removed from a future version.  Calls to
>   :command:`cmake_minimum_required` or :command:`cmake_policy` that set
>   the policy version to an older value now issue a deprecation diagnostic.

> From b9e521ef5e9c01d8d19f505de778ceaef5ecd4eb Mon Sep 17 00:00:00 2001
> From: Matthias Schwarzott <zzam@gentoo.org>
> Date: Tue, 28 Oct 2025 07:52:00 +0100
> Subject: [PATCH] CMakeLists.txt: Require cmake 3.10 or higher
> 
> To fix this warning from cmake:
> 
> CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required):
>   Compatibility with CMake < 3.10 will be removed from a future version of
>   CMake.
> 
>   Update the VERSION argument <min> value.  Or, use the <min>...<max> syntax
>   to tell CMake that the project requires at least <min> but has been updated
>   to work with policies introduced by <max> or earlier.
> 
> Signed-off-by: Matthias Schwarzott <zzam@gentoo.org>
> ---
>  CMakeLists.txt | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/CMakeLists.txt b/CMakeLists.txt
> index eb873000d7bf..91522c1382a5 100644
> --- a/CMakeLists.txt
> +++ b/CMakeLists.txt
> @@ -1,4 +1,4 @@
> -cmake_minimum_required(VERSION 3.5)
> +cmake_minimum_required(VERSION 3.10)
>  project(pahole C)
>  cmake_policy(SET CMP0005 NEW)
>  
> -- 
> 2.51.0
> 

Re: pahole: Fix deprecated cmake_minimum_required

[Matthias Schwarzott]

Am 28.10.25 um 15:53 schrieb Arnaldo Carvalho de Melo:
> On Tue, Oct 28, 2025 at 07:58:17AM +0100, Matthias Schwarzott wrote:
>> I got to know that using a cmake_minimum_required version of less than 3.10
>> is deprecated. Support for it will be removed from cmake.
> 
> Support for what? For features present before 3.10? So we better make
> sure that we have pahole use that 'cmake_minimum_required(3.10)' so that
> we don't end up using such deprecated cmake features and end up breaking
> the build in distros using, say, cmake 3.11?

Similar. If we declare cmake_minimum_version less than 3.10 then a new 
released cmake-4.3 might error out similar to this (when I reduce 
min-version to 3.0):

   CMake Error at CMakeLists.txt:1 (cmake_minimum_required):
     Compatibility with CMake < 3.5 has been removed from CMake.

     Update the VERSION argument <min> value.  Or, use the <min>...<max> 
syntax
     to tell CMake that the project requires at least <min> but has been 
updated
     to work with policies introduced by <max> or earlier.

     Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway.

> 
> Please CC dwarves@vger.kernel.org when sending patches, like I did in
> this reply :-)

Good to know.

Regards
Matthias

> 
> Thanks!
> 
> - Arnaldo
>   
>> I suggest to raise the minimum required cmake version to at least 3.10
>> (released 20 November 2017).
>> See attached patch.
> 
>> see gentoo pahole issue: https://bugs.gentoo.org/964482
>> gentoo overall issue: https://bugs.gentoo.org/964405
>   
>> cmake merge request:
>> https://gitlab.kitware.com/cmake/cmake/-/merge_requests/9875
>   
>> deprecate-pre-3.10
>> ------------------
>   
>> * Compatibility with versions of CMake older than 3.10 is now deprecated
>>    and will be removed from a future version.  Calls to
>>    :command:`cmake_minimum_required` or :command:`cmake_policy` that set
>>    the policy version to an older value now issue a deprecation diagnostic.
> 
>>  From b9e521ef5e9c01d8d19f505de778ceaef5ecd4eb Mon Sep 17 00:00:00 2001
>> From: Matthias Schwarzott <zzam@gentoo.org>
>> Date: Tue, 28 Oct 2025 07:52:00 +0100
>> Subject: [PATCH] CMakeLists.txt: Require cmake 3.10 or higher
>>
>> To fix this warning from cmake:
>>
>> CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required):
>>    Compatibility with CMake < 3.10 will be removed from a future version of
>>    CMake.
>>
>>    Update the VERSION argument <min> value.  Or, use the <min>...<max> syntax
>>    to tell CMake that the project requires at least <min> but has been updated
>>    to work with policies introduced by <max> or earlier.
>>
>> Signed-off-by: Matthias Schwarzott <zzam@gentoo.org>
>> ---
>>   CMakeLists.txt | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/CMakeLists.txt b/CMakeLists.txt
>> index eb873000d7bf..91522c1382a5 100644
>> --- a/CMakeLists.txt
>> +++ b/CMakeLists.txt
>> @@ -1,4 +1,4 @@
>> -cmake_minimum_required(VERSION 3.5)
>> +cmake_minimum_required(VERSION 3.10)
>>   project(pahole C)
>>   cmake_policy(SET CMP0005 NEW)
>>   
>> -- 
>> 2.51.0
>>
> 

Re: pahole: Fix deprecated cmake_minimum_required

[Matthias Schwarzott]

Am 05.11.25 um 08:00 schrieb Matthias Schwarzott:
> Am 28.10.25 um 15:53 schrieb Arnaldo Carvalho de Melo:
>> On Tue, Oct 28, 2025 at 07:58:17AM +0100, Matthias Schwarzott wrote:
>>> I got to know that using a cmake_minimum_required version of less 
>>> than 3.10
>>> is deprecated. Support for it will be removed from cmake.
>>
>> Support for what? For features present before 3.10? So we better make
>> sure that we have pahole use that 'cmake_minimum_required(3.10)' so that
>> we don't end up using such deprecated cmake features and end up breaking
>> the build in distros using, say, cmake 3.11?
> 
> Similar. If we declare cmake_minimum_version less than 3.10 then a new 
> released cmake-4.3 might error out similar to this (when I reduce min- 
> version to 3.0):
> 
>    CMake Error at CMakeLists.txt:1 (cmake_minimum_required):
>      Compatibility with CMake < 3.5 has been removed from CMake.
> 
>      Update the VERSION argument <min> value.  Or, use the <min>...<max> 
> syntax
>      to tell CMake that the project requires at least <min> but has been 
> updated
>      to work with policies introduced by <max> or earlier.
> 
>      Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway.
> 

Is there a reason to not add it to the repository? Sadly it is not part 
of v1.31.

If you want the change to be even less harmful could also be changed to:

   cmake_minimum_required(VERSION 3.5...3.10)

The point is: Distributions will most likely have to patch pahole with 
the next cmake release that really changes the minimal version for 
cmake_minimum_required.

Regards
Matthias

>>
>> Please CC dwarves@vger.kernel.org when sending patches, like I did in
>> this reply :-)
> 
> Good to know.
> 
> Regards
> Matthias
> 
>>
>> Thanks!
>>
>> - Arnaldo
>>> I suggest to raise the minimum required cmake version to at least 3.10
>>> (released 20 November 2017).
>>> See attached patch.
>>
>>> see gentoo pahole issue: https://bugs.gentoo.org/964482
>>> gentoo overall issue: https://bugs.gentoo.org/964405
>>> cmake merge request:
>>> https://gitlab.kitware.com/cmake/cmake/-/merge_requests/9875
>>> deprecate-pre-3.10
>>> ------------------
>>> * Compatibility with versions of CMake older than 3.10 is now deprecated
>>>    and will be removed from a future version.  Calls to
>>>    :command:`cmake_minimum_required` or :command:`cmake_policy` that set
>>>    the policy version to an older value now issue a deprecation 
>>> diagnostic.
>>
>>>  From b9e521ef5e9c01d8d19f505de778ceaef5ecd4eb Mon Sep 17 00:00:00 2001
>>> From: Matthias Schwarzott <zzam@gentoo.org>
>>> Date: Tue, 28 Oct 2025 07:52:00 +0100
>>> Subject: [PATCH] CMakeLists.txt: Require cmake 3.10 or higher
>>>
>>> To fix this warning from cmake:
>>>
>>> CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required):
>>>    Compatibility with CMake < 3.10 will be removed from a future 
>>> version of
>>>    CMake.
>>>
>>>    Update the VERSION argument <min> value.  Or, use the 
>>> <min>...<max> syntax
>>>    to tell CMake that the project requires at least <min> but has 
>>> been updated
>>>    to work with policies introduced by <max> or earlier.
>>>
>>> Signed-off-by: Matthias Schwarzott <zzam@gentoo.org>
>>> ---
>>>   CMakeLists.txt | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/CMakeLists.txt b/CMakeLists.txt
>>> index eb873000d7bf..91522c1382a5 100644
>>> --- a/CMakeLists.txt
>>> +++ b/CMakeLists.txt
>>> @@ -1,4 +1,4 @@
>>> -cmake_minimum_required(VERSION 3.5)
>>> +cmake_minimum_required(VERSION 3.10)
>>>   project(pahole C)
>>>   cmake_policy(SET CMP0005 NEW)
>>> -- 
>>> 2.51.0
>>>
>>
>