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Date: Mon, 26 Feb 2018 08:43:00 -0000
From: "Ruslan Nikolaev via gcc" <gcc@gcc.gnu.org>
Reply-To: Ruslan Nikolaev <nruslan_devel@yahoo.com>
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To: Alexander Monakov <amonakov@ispras.ru>
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Subject: Re: Fw: GCC interpretation of C11 atomics (DR 459)
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> I'd say the main issue is that libatomic is not guaranteed to work like that.


> Today it relies on IFUNC for redirection, so you may (and not "will") get the
> desired behavior on Glibc (implying Linux), not on other OSes, and neither on
> Linux with non-GNU libc (nor on bare metal, for that matter).
I think, in case if IFUNC is not available (i.e., outside glibc), redirection is still possible by introducing a regular function pointer there. Yes, it is an extra cost but better than nothing (+ consistent behavior on all platforms), probably will not add too much anyway because there is already a performance hit by going to libatomic.