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On Mon, 25 May 2020 11:26:26 -0400 |
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Mike Gilbert <floppym@g.o> wrote: |
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> On Mon, May 25, 2020 at 9:13 AM Alexis Ballier <aballier@g.o> |
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> wrote: |
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> > |
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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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> > |
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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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> > |
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> > |
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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 |
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> > of performance, so it is enabled by default on hardened profiles |
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> > and not others. |
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> > Textrels work fine (on some architectures), they disallow W^X and |
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> > force each process using the shared lib to make a "copy" at runtime |
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> > in order to resolve relocations, so are not desirable but sometimes |
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> > the cost outweights the gain. |
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> > |
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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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> |
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> The USE flag toggles use of assembly, not use of PIC. The default USE |
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> value in the hardened profile should not drive decisions on what we |
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> name USE flags. |
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... but using a global well documented useflag instead of a local |
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invention should drive such decisions. |
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> |
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> You can add the flag to package.use or package.use.mask in the |
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> hardened profile if necessary. |
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Sure but it was not added there and it's not really relevant here since |
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USE=asm does not make any sense either. (aka: this was better |
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before this series of commits) |
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