On Mon, 2021-11-08 at 12:18 +0100, Michał Górny wrote: > Hi, > > A few years back I've slotted LLVM and Clang to make the life with > revdeps easier. Long story short, every major LLVM release (which > happens twice a year) breaks API and it takes some time for revdeps to > adjust. Slotting made it possible to install multiple versions > simultaneously, and therefore let "faster" packages use newer LLVM > without being blocked by "slower" packages on the user's system. > > Unfortunately, this ended up pretty bothersome to maintain. Besides > making ebuilds quite complex (and prone to mistakes), I'm hearing more > and more reports of programs being broken through getting multiple LLVM > versions in the link chain. > > This is not something that can be easily solved. In other words, it's > a mess and I don't think we're really getting anywhere. For this > reason, I'm considering dropping slotting and going back to permitting > only a single version of LLVM and Clang being installed. > > This would have two major implications: > > 1. If you installed any package that requires older LLVM, it'd block all > other packages from updating. If you hit two packages that do not have > a common supported LLVM version, you won't be able to install them > at all. > > On the plus side, this will motivate developers to actually start fixing > these packages rather than letting them rot until I start removing old > LLVM versions. > > 2. We will no longer support having multiple clang versions installed. > While it was convenient for testing stuff, it's not really a killer > feature though. > > The only real alternative I see is actively limiting supported LLVM > versions in packages to ensure that all libraries in the depgraph end up > using the same LLVM version. However, I don't think it's really worth > the effort. > > I don't have a ready unslotting plan yet. > > WDYT? >
I've got the message and slotted LLVM and Clang are going to stay for the time being. -- Best regards, Michał Górny
