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On Sun, 24 May 2020 20:25:11 +0000 (UTC) |
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"Thomas Deutschmann" <whissi@g.o> wrote: |
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> commit: 6e149596cc76f1bbcee6720828c8c8c92420f2a3 |
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> Author: Thomas Deutschmann <whissi <AT> gentoo <DOT> org> |
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> AuthorDate: Sun May 24 19:47:08 2020 +0000 |
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> Commit: Thomas Deutschmann <whissi <AT> gentoo <DOT> org> |
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> CommitDate: Sun May 24 20:23:53 2020 +0000 |
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> URL: |
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> https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=6e149596 |
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> |
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> media-libs/x265: drop USE=pic |
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> |
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> Gentoo's toolchain uses PIC by default. Since USE=asm was added, |
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> we no longer need a USE flag to control that behavior. |
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You got it wrong here it seems: USE=pic does not control whether |
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the toolchain produces PIC or not. Shared libs always are, and have |
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always been, built that way on Gentoo. |
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In this case, USE=pic means "no matter what it costs, I do not want |
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textrels", for the cases of hand written assembly that has to be |
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rewritten to support PIC. And, still in this case, this costs a lot of |
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performance, so it is enabled by default on hardened profiles and not |
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others. |
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Textrels work fine (on some architectures), they disallow W^X and force |
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each process using the shared lib to make a "copy" at runtime in order |
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to resolve relocations, so are not desirable but sometimes the cost |
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outweights the gain. |
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Plus, profiles/features/hardened enables pic by default but knows |
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nothing about USE=asm so this is a regression for them. |
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Alexis. |