[LAD] library soname, was Re: Rubber Band Library v3.0.0 released

[Chris Cannam]

On Thu, 28 Jul 2022, at 17:06, Robin Gareus wrote:
> On 7/28/22 15:52, Chris Cannam wrote:
>> 
>> The version in the .pc file is written in at install time,
>
> Except, it isn't. $PREFIX/lib/pkgconfig/rubberband.pc here has Version:
> 1.8.2 for rubberband v3.0.0

Oops. How are you installing? If I use e.g. "meson build && ninja -C build && ninja -C build install" here I get a copy that does have the right version in it. I haven't looked too closely at how it does that though. Since it appears to work equally well with %VERSION% in the .in file, and it's obviously not great to have a wrong literal value in there, I'll make that change.

>> The ABI has been at 2.something since version 1.2, 
>
> Yeah that's fine. I was just surprised to see the age being zero.
>
> http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html

That page just makes my head spin a little faster if anything! It seems rather libtool-specific and doesn't indicate how current:revision:age maps on to the installed library suffix. Is "current" the soname number, "revision" the minor number, and "age" the point number, as I would naively read it?

If so, then it appears to be saying that merely adding a function *should* result in incrementing the soname:

"If any interfaces have been added, removed, or changed since the last update, increment current, and set revision to 0"

where "current" is the soname, right?

As I read it, it seems to be saying that if the current version is (say) 2.1.7, then a backward-compatible addition should result in an updated version 3.0.8 whereas an incompatible change should result in 3.0.0. I'm not sure I understand the logic regardless of the explanation in the page. I don't recall having ever read quite that method before.


Chris