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Date: Fri, 02 Dec 2016 21:57:00 -0000
From: Joseph Myers <joseph@codesourcery.com>
To: Dave Martin <Dave.Martin@arm.com>
CC: Florian Weimer <fweimer@redhat.com>, <libc-alpha@sourceware.org>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Marc Zyngier <Marc.Zyngier@arm.com>,	<gdb@sourceware.org>, Yao Qi <qiyaoltc@gmail.com>,	<linux-arm-kernel@lists.infradead.org>, Alan Hayward <alan.hayward@arm.com>,	Torvald Riegel <triegel@redhat.com>, Christoffer Dall	<christoffer.dall@linaro.org>
Subject: Re: [RFC PATCH 00/29] arm64: Scalable Vector Extension core support
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On Fri, 2 Dec 2016, Dave Martin wrote:

> Presumably the C language specs specify that fenv manipulations cannot
> be reordered with respect to evaluation or floating-point expressions?

Yes (in the context of #pragma STDC FENV_ACCESS ON).  And you need to 
presume that an arbitrary function call might manipulate the environment 
unless you know it doesn't.

-- 
Joseph S. Myers
joseph@codesourcery.com