The current SLOT used by dev-util/lttng-ust simply repeatd the version number and don't reflect the ABI number. As of 2.13 the ABI bumped from liblttng-ust.so.0.0.0 to liblttng-ust.so.1.0.0. Unfortunately the current slot identifiers don't allow for a dependency on all-packages-that-support-ABI-0 versus all-packages-that-support-ABI-1. Since it's already possible to encode the version number into the package name, the SLOT value isn't overly useful. According to the devmanual (devmanual.gentoo.org/general-concepts/slotting/index.html#general-naming-of-a-sub-slot), it's recommended that the SLOTs would be something like "0/0" for <= 2.12 and "0/1" for > 2.12.
(In reply to Mike Auty from comment #0) > The current SLOT used by dev-util/lttng-ust simply repeatd the version > number and don't reflect the ABI number. As of 2.13 the ABI bumped from > liblttng-ust.so.0.0.0 to liblttng-ust.so.1.0.0. > > Unfortunately the current slot identifiers don't allow for a dependency on > all-packages-that-support-ABI-0 versus all-packages-that-support-ABI-1. > Since it's already possible to encode the version number into the package > name, the SLOT value isn't overly useful. I'm not sure I get this bit. Usually, we set something like SLOT="0/${PV}" when something's ABI is unstable and SONAME isn't reliably bumped. The subslot is then used to automatically trigger rebuilds in consumers. > > According to the devmanual > (devmanual.gentoo.org/general-concepts/slotting/index.html#general-naming-of- > a-sub-slot), it's recommended that the SLOTs would be something like "0/0" > for <= 2.12 and "0/1" for > 2.12. See above, but if upstream are now reliably using SONAME for ABI breaks, I think we could do that?
You're right, I can't verify whether lttng-ust correctly used the ABI number (and therefore whether 2.11 and 2.12 would both satisfy the appropriate dependency) but they have now started bumping the ABI. In either instance, since the version number is already encoded in the PV field, I'm, not sure how making it part of the SLOT helps filter in anyway which is why I suggested making the SLOT match the ABI (even if it wasn't getting bumped). Is there value in using "dev-util/lttng-ust:0/2.12" over "=dev-util/lttng-ust-2.12"?
