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