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Hi, |
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TL;DR: I'd like to move virtual/libjpeg, virtual/libudev and so on to |
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another category (e.g. lib-sover/*) to make it clear that they are used |
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for := deps and have valid use even with a single provider. |
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Right now we have at least a few packages that provide more than one |
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valid consumer-intended library, each with a different SOVERSION that is |
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bumped independently. To list a few examples: |
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|
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- media-libs/libjpeg-turbo: libturbojpeg.so.0, libjpeg.so.62 |
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- sys-apps/systemd: libsystemd.so.0, libudev.so.1 |
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- app-text/poppler: libpoppler.so.106, libpoppler-cpp.so.0, libpoppler- |
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glib.so.8, libpoppler-qt5.so.1 |
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|
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The problem is that the current subslot mechanism doesn't really provide |
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for that. Laying aside possible future EAPI extensions (that are |
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debatable due to added complexity to an already complex syntax), there |
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are three commonly used possibilities here: |
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|
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a. bumping subslot whenever any of SOVERSIONs change -- meaning possibly |
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unnecessary rebuilds, |
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|
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b. using subslot for one of the SOVERSIONs and assuming the rest stable |
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-- this is what we do for poppler, and it's mildly confusing, |
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c. using additional packages to represent SOVERSION of individual |
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libraries -- this is e.g. used for libudev or libjpeg. |
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I'd like to discuss option c. in more detail. Right now, we're creating |
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additional packages in virtual/ category. This was mostly fine, |
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as the libraries in question (libjpeg, libudev) had multiple providers. |
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However, now that we've removed the old media-libs/jpeg, people get |
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the obvious idea that the virtual is no longer necessary -- except that |
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it is! |
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|
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The rough idea is that the subslot of libjpeg-turbo is supposed to |
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represent the ABI version of libjpeg-turbo -- that is actually rarely |
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used. On the other hand, the subslot of libjpeg is represented by |
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virtual/jpeg. So if your package is using libjpeg.so, it should :=- |
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depend on the latter and not on the former. |
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The problem is that this is confusing, and if somebody doesn't know |
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the secret, he can easily consider the virtual obsolete and depend |
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on the library directly. |
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To make this SOVERSION-virtual concept more visible and easily |
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distinguishable from regular virtuals, I'd like to propose that we start |
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moving them into a dedicated category. For example, 'lib-sover' comes |
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to my mind. While this ofc doesn't guarantee that people will do things |
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right, it will at least make it clear that these packages are somewhat |
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different from regular virtuals and hopefully avoid making wrong |
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assumptions. |
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|
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WDYT? |
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|
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-- |
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Best regards, |
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Michał Górny |
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