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Date: Wed, 12 Feb 2014 13:15:00 -0000
Message-ID: <CAG3jReLSb1Xn12W+Lrfr_Qcp-POug8FOA9acoytCntbW9XesWA@mail.gmail.com>
Subject: Re: Fwd: LLVM collaboration?
From: =?UTF-8?Q?Rafael_Esp=C3=ADndola?= <rafael.espindola@gmail.com>
To: Richard Biener <richard.guenther@gmail.com>
Cc: Jan Hubicka <hubicka@ucw.cz>, Renato Golin <renato.golin@linaro.org>, gcc <gcc@gcc.gnu.org>
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> What about instead of our current odd way of identifying LTO objects
> simply add a special ELF note telling the linker the plugin to use?
>
> .note._linker_plugin '/...../libltoplugin.so'
>
> that way the linker should try 1) loading that plugin, 2) register the
> specific object with that plugin.
>
> If a full path is undesired (depends on install setup) then specifying
> the plugin SONAME might also work (we'd of course need to bump
> our plugins SONAME for each release to allow parallel install
> of multiple versions or make the plugin contain all the
> dispatch-to-different-GCC-version-lto-wrapper code).

Might be an interesting addition to what we have, but keep in mind
that LLVM uses thin non-ELF files. It is also able to load IR from
previous versions, so for LLVM at least, using the newest plugin is
probably the best default.

> Richard.

Cheers,
Rafael