Dear Robie, thanks for paying attention to this bug!
>Has this been fixed in the development release, and if so, how? LXC_DEVEL is 1 in the development release: https://github.com/lxc/lxc/blob/main/meson.build#L36 But LXC_DEVEL is 0 in *any* stable tag: https://github.com/lxc/lxc/blob/lxc-5.0.3/meson.build#L36 And this is correct. >It's not clear to me that making this change is the appropriate thing to do in an SRU. How is LXC_DEVEL used in practice? LXC_DEVEL is used to determine if the liblxc is a cutting-edge development snapshot of the LXC or not. So, it should be 1 *only* for the main branch of lxc. But in all stable version it is 0. > Have you analysed known reverse dependencies to understand the impact of making this change? What did you find? I have analyzed well-known reverse dependency go-lxc. It's used by LXD to communicate with liblxc C API. >The only impact to users that I can understand from your explanation is that VERSION_AT_LEAST is disabled, causing builds outside the archive that use that macro to fail. Everything else seems to make the assumption that the correct way to fix this is to change LXC_DEVEL from 1 to 0, but without explaining why this is the minimal change possible. Speaking honestly, I have no idea about other good ways to fix this. And this change seems to be a "minimal" for me because it does not change LXC code (and should not) it's just a matter of having proper build configuration. >Is there any other actual real world impact? I don't think that changing LXC_DEVEL to 0 can break any properly written code. For example, Debian folks have it disabled: https://git.launchpad.net/ubuntu/+source/lxc/tree/meson.build?h=applied/debian/bookworm#n36 >Could you just patch to make VERSION_AT_LEAST work instead, for SRU purposes, to minimise regression risk? Of course, we can patch go-lxc (go-lxc also part of the LXC project). But this will be a hacky and incorrect way to fix things. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lxc in Ubuntu. https://bugs.launchpad.net/bugs/2039873 Title: liblxc-dev was built with LXC_DEVEL=1 in Ubuntu Jammy/Kinetic Status in lxc package in Ubuntu: Confirmed Bug description: [ Impact ] LXC 5.0.0 was built with LXC_DEVEL=1 set for Jammy. But for release build we should have LXC_DEVEL=0. LXC_DEVEL is a variable that appears in the /usr/include/lxc/version.h and then can be (and actually it is) used by other projects to detect if liblxc-dev is a development build or stable. Having LXC_DEVEL=1 makes problems for the users who want to build projects those are depend on liblxc from source (for example, LXD, go-lxc: https://github.com/canonical/lxd/pull/12420). Q: Why it was not a problem for so long? A: Because LXC API was stable for a long time, but recently we have extended liblxc API (https://github.com/lxc/lxc/pull/4260) and dependant package go-lxc was updated too (https://github.com/lxc/go-lxc/pull/166). This change was developed properly to be backward compatible with the old versions of liblxc. But, there is a problem. If LXC_DEVEL=1 then the macro check VERSION_AT_LEAST (https://github.com/lxc/go-lxc/blob/ccae595aa49e779f7ecc9250329967aa546acd31/lxc-binding.h#L7) is disabled. That's why we should *not* have LXC_DEVEL=1 for *any* release build of LXC. [ Test Plan ] Install liblxc-dev package and check /usr/include/lxc/version.h file LXC_DEVEL should be 0 [ Where problems could occur ] Theoretically, build of a software which depends on liblxc-dev may start to fail if it assumes that LXC_DEVEL is 1. [ Other Info ] - To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/2039873/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
