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Robert Moss posted <41A10443.2070108@g.o>, excerpted below, on |
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Sun, 21 Nov 2004 21:10:27 +0000: |
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> No, this is wrong. On amd64, you should *not* use -fPIC in make.conf. |
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> That's been policy since 2004.0. It is required that -fPIC is used for |
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> shared things (such as shared libraries) and it is required that -fPIC is |
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> not used for non-shared things (such as binaries). Thus, it must not be |
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> set in make.conf, otherwise you break this. If something does not compile |
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> without using -fPIC in CFLAGS, then that is a bug. |
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> |
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> Hardened is different, however. |
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> |
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> Duncan wrote: |
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>> No, not all archs follow x86 (or whatever arch rules you are assuming) |
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>> rules. On some archs (amd64 comes to mind as that's what I use), -fPIC |
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>> is required. Gentoo amd64 officially discourages it in make.conf, so as |
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>> to hilite ebuilds which do NOT set it so they can be patched to do so, |
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>> but it's required on the arch, regardless, whether it's configured in |
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>> the source, in the ebuild, or in make.conf, so on some archs anyway, |
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>> it's NOT wrong to have it in make.conf, hardened or not. |
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That's why I said "Gentoo officially discourages". |
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As for required, you are correct that it's "required" for shared libs on |
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amd64. However, you are incorrect in that it's NOT "required that it be |
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OFF for unshared ELF executables, because the fact that I can type this |
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message and send it on such a system, in PAN, on KDE, on X, on Gentoo for |
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amd64, with -fPIC in my CFLAGS when I compiled a good share of |
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what's running, indicates that it cannot be a "requirement" for it to be |
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off in those cases in the same way that it's "required" to be on (on pain |
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of compile error) for libraries. |
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As I stated, "Gentoo officially discourages" setting it in CFLAGS, for bug |
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hunting and reporting reasons, but it works, and some of use use it even |
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on non-hardened (because hardened did NOT work here, couldn't run xorg) |
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because we like the idea of "position independent code" even in our |
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executables, with the fact that it prevents occasional hassles with |
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unpatched libs where it's definitely required, just a very pleasant side |
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effect. |
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"They that can give up essential liberty to obtain a little |
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temporary safety, deserve neither liberty nor safety." -- |
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Benjamin Franklin |
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-- |
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