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As portage-2.2 is about to be unmasked into ~arch soon (there is one |
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weird bug to solve before) it's time to ask for some input on one of |
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the important new features, FEATURES=preserve-libs. |
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|
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(if you're already familiar with it you can skip this paragraph) |
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Simply said, when this feature is enabled portage keeps track of all |
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installed libraries and binaries linked against them, and if a package |
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upgrade would remove a library that's still in use portage will keep |
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the library around, owned by the new version and also registered in a |
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separate file. There is also an internal package set that can be used |
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to rebuild all packages linked against libraries preserved in this way, |
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and the user is notified after each emerge operation that he should do |
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that (the example is from an expat downgrade in case you wonder about |
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the versions): |
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!!! existing preserved libs: |
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>>> package: dev-libs/expat-1.95.8 |
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* - /usr/lib64/libexpat.so.1 |
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* - /usr/lib64/libexpat.so.1.5.2 |
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Use emerge @preserved-rebuild to rebuild packages using these libraries |
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|
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The purpose of this is to keep the system operational after library |
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upgrades until all affected packages could be rebuilt and to simplify |
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the process, not to avoid the rebuilds. |
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|
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Now the question is if this behavior should be enabled by default? |
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|
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In the existing prereleases it has been enabled to get some real-world |
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testing, and it's been quite effective, though there are still a few |
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issues to be worked out (e.g. if libraries are moved between packages). |
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And no doubt a few more bugs will turn up over time. |
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Also it is not going to be a perfect solution against all runtime link |
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errors, but if enabled it should eliminate the need for revdep-rebuild |
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in most cases. |
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One concern raised by some people is that it might cause old libraries |
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with security issues to stay on the system for eternity even though |
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the package was upgraded, and eventually be preferred by new builds. |
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I can't rule this out completely but thinks it's very unlikely, as |
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preserved libraries are specially tracked and the user is notified |
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about their existance after every emerge operation (similar to glep42 |
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news). And new builds shouldn't find them as the unversioned .so |
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symlinks ar going to point to the current versions. |
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So personally I'm not too worried about this concern becoming reality, |
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but I can understand if others are. |
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|
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So, do you think it should be enabled by default? |
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|
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Marius |
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|
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PS: Obviously, if you haven't tested portage-2.2 yet, now would be a |
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good time. |
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|
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-- |
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Public Key at http://www.genone.de/info/gpg-key.pub |
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|
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In the beginning, there was nothing. And God said, 'Let there be |
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Light.' And there was still nothing, but you could see a bit better. |
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