[dpdk-dev] [PATCH v3 0/4] abi breakage checks for meson

[Kinsella, Ray]

(apologies for re-sending, I missed the CC list the 1st time). 

Predictably perhaps, I disagree.

On 14/09/2020 09:08, Thomas Monjalon wrote:
> Hi,
> 
>> This patchset allows developers to check ABI breakages during build
>> time.
>> Currently checking that the DPDK ABI has not changed before up-streaming
>> code is not intuitive. The current method, requires the contributor to
>> use either the test-build.sh and test-meson-build.sh tools, along side
> 
> The contributor *MUST* test compilation with test-meson-build.sh in any case.
> 

So I guess, you need to ask what the "user interface" is for DPDK.
The reality is that is meson/ninja (or previously make) tooling is that interface.
as it is most other places, dev's expect a familiar build system.

>> some environmental variables to test their changes. Contributors in many
> 
> It is just one variable to add to a file:
> 	export DPDK_ABI_REF_VERSION=v20.11
> in ~/.config/dpdk/devel.config or dpdk/.develconfig

It's a documentation heavy, non-obvious process.
We need to consider UX, to make it as _easy_ as possible, 
integrated with the build system and automated. 

> 
>> cases are either unaware or unable to do this themselves, leading to a
>> potentially serious situation where they are unknowingly up-streaming
>> code that breaks the ABI. These breakages are then caught by Travis, but
>> it is more efficient if this is caught locally before up-streaming.

This is puzzling, complex compared to running a separate script to meson/ninja, 
and requiring that esoteric environment variables are set?

> I think you are proposing a complex solution to a non-issue.
> 
> And I don't understand how your method is more straight-forward
> for the user, given this statement in your last patch:
> "
> This patch adds the ability to run ABI breakage checks to meson.
> To do this the developer needs to set the meson build type to debug and
> set the version of DPDK that they want to check the ABI against.
> "
> 

The developer can set the abi-check option to latest, and the build system
will take care of the rest. The system even caches the debug symbols, so they 
don't need to be generated locally.