Discussion: How to handle HALs, SDKs and libraries

[oss at c-mauderer.de]

Hello Karel,

Am 16.07.23 um 12:37 schrieb Karel Gardas:
> On 7/16/23 10:03, oss at c-mauderer.de wrote:
>>>> Of course the revision from two months back has to be available in 
>>>> the repo. It doesn't really matter whether it's on master because 
>>>> the code just worked or whether it's a RTEMS specific branch because 
>>>> adaptions have been necessary.
>>>
>>> You "it doesn't really matter" worries me a little bit. I'm not sure 
>>> this functionality is even supported hence my question above if you 
>>> have tested it yourself.
>>
>> Yes, I use that regularly. For an (old) example, take a look at a 
>> branch in the repo that I use to test GSoC work:
>>
>>    https://gitlab.com/c-mauderer/rtems-bbb/-/tree/6
>>
>> I have a libs/rtems-libbsd submodule there that uses the revision 
>> c9474c0b which is on a cm/20200726_fix branch in my clone of 
>> rtems-libbsd. In the .gitmodules the branch is still set to "master". 
>> Despite that, git can find thre right commit ID.
> 
> Cool! So it didn't work for me due to (i) my git bug or (ii) my git 
> doesn't supporting whatever or simply due to (iii) me making silly 
> mistake somewhere.
> 
> Will need to recheck this. Thanks for the info!
> 
> Karel
> 
> 

Seems that we are not the only ones with a waf based build system that 
want to manipulate submodules:

https://github.com/ArduPilot/ardupilot/pull/3592

The final solution seems to be a bit different. Their wscript in the 
latest version has a "--no-submodule-update" parameter. So they decided 
to just update the submodules every time. Can be interesting for users 
because they don't have to care for outdated submodules if they pull a 
new version.

But I think the problem with adding it as a fixed step is, that we have 
a problem with the releases. A release tar ball is not a git repo 
anymore. So a "git submodule init --update" or similar will not work. We 
would need some mechanism to detect whether it's a git repo or not.

Best regards

Christian