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Hi, |
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On 9/02/2013 23:15, Alexis Ballier wrote: |
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> Dear fellow developers, |
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> |
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> I hope this will be trivial to most of you but after seeing bug #455900 |
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> and the vast majority of developers not even thinking twice before |
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> sedding their dep strings, I believe this needs some attention. |
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|
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What is wrong with maintainers just updating their dependencies in this |
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fashion? Surely the onus in this case is on package maintainers setting |
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sensible subslots (which is indeed what you appear to be saying below)? |
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|
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I even noticed some maintainers adding subslots dependencies on |
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libraries that do not yet define subslots. This too seems reasonable, |
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given that there would be no impact until the library defines a |
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(sensible) subslot in the future. |
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|
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> |
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> What do subslots do: You set a subslot to a package and every time said |
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> package subslot changes (e.g. with an update), others packages |
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> depending on it with a := dep will be rebuilt. Nothing more, nothing |
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> less. |
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> |
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> Now, this solves a real problem: haskell, perl and ocaml packages need |
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> to be rebuilt after updating their respective compiler/interpreter and, |
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> in some cases, even after updating the libraries they use. Subslots |
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> would make haskell-updater, perl-cleaner and ocaml-rebuild not needed |
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> in the future. |
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> |
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> You can also use subslots to notify an ABI change in a shared library, |
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> in order to avoid having to use preserve-libs or run revdep-rebuild. |
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> However, this week I had to rebuild webkit-gtk three or four times and |
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> libreoffice twice... |
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> If you want to notify ABI changes, then you should set subslot to |
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> something representing the ABI, $PV as subslot is most certainly wrong |
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> in that case. Subslot is *not* a substitute to checking your library |
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> ABI, checking if its reverse dependencies work fine after the update, |
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> and notifying upstream if something went wrong so they can make a quick |
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> release fixing their mistake. Subslot is also *not* a substitute to |
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> soname and ensuring ABI compatibility (at least forward) between |
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> libraries with the same major. Using subslot only to be on the safe |
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> side and forcing a rebuild of all the dependent packages because it is |
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> too much work to check the ABI and work with upstream is, IMHO, a |
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> serious QA issue. |
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> |
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> Thank you for your attention, |
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> |
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> Alexis. |
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> |
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> |
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|
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Best regards, |
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Michael |
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