Multi-versioning for backward compatibility

Multi-versioning for backward compatibility

[Arseniy Aharonov]

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Hi,

In the codebase of DPDK I saw that it uses the glibc approach<https://developers.redhat.com/blog/2019/08/01/how-the-gnu-c-library-handles-backward-compatibility> to mangle symbol names with a library version to maintain different implementations of the same function per version.
So that applications which were compiled with different versions of the library will link to a proper version of the function that corresponds to the right glibc (see doc<https://doc.dpdk.org/guides/contributing/abi_versioning.html>).
This method can't work in Windows with MSVC (at least to the best of my knowledge).

How does DPDK solve if in Windows for MSVC? I failed to find the answer.

Thank you,
Arseniy Aharonov

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Re: Multi-versioning for backward compatibility

[Dmitry Kozlyuk]

2023-02-01 14:54 (UTC+0000), Arseniy Aharonov:
> This method can't work in Windows with MSVC (at least to the best of my knowledge).

In Windows generally, not limited to MSVC.
 
> How does DPDK solve if in Windows for MSVC? I failed to find the answer.

It just doesn't.

Fortunately, symbol versioning is not the approach used in DPDK by default.
For example, there are currently no versioned symbols AFAICT.
The preferred approach is:
1) to keep new functions experimental (there are precise rules for how long)
2) to consider possible future extensions when defining new APIs