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В Чт, 27/09/2018 в 15:45 +0200, Hanno Böck пишет: |
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> On Fri, 21 Sep 2018 00:16:48 +0100 |
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> Luis Ressel <aranea@×××××.de> wrote: |
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> |
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> > On Wed, 19 Sep 2018 09:24:27 +0200 |
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> > Hanno Böck <hanno@××××××.de> wrote: |
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> > |
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> > > If the flag just disables assembly optimizations then I wonder if |
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> > > it |
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> > > should be renamed (or if we need it at all - in case these |
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> > > assembly |
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> > > optimizations have no downsides). |
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> > |
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> > Many (all?) of the ebuilds with this flag do indeed only disable |
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> > assembly snippets, and most of them only do this on 32-bit x86 |
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> > (gzip |
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> > being the prominent exception). |
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> |
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> And ffmpeg and mesa. |
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> |
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> In ffmpeg the flag description says: |
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> "Force shared libraries to be built as PIC (this is slower)" |
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> |
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> Which confuses me - I thought shared libraries are always PIC. |
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> |
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> It looks to me these are all historic leftovers, but I'd like to |
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> understand it better before I open bugs asking for removal of these |
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> flags. |
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|
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IIRC the main issue was a limited general purpose register set on x86 |
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architecture. |
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https://wiki.gentoo.org/wiki/Hardened/Toolchain#Issues_with_PIEs |
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|
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"Occasionally application code will fail to compile with -fPIE. If this |
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happens it is usually down to non-position-independent assembler code, |
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and is most prevelant on X86 which has a limited general purpose |
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register set." |
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|
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I guess a lot of programs was fixed since then. For example currently I |
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don't see any problems when building mesa with USE=-pic on x86_32. |
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