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From: Martin Vaeth <martin@mvath.de>
Subject: [gentoo-user] Re: CFLAGs for kernel compilation
Date: Fri, 1 May 2015 05:09:51 +0000 (UTC)
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References: <5540C101.70906@ramses-pyramidenbau.de>
 <20150430123819.b72d8b39bd60a912b7c7fde5@gentoo.org>
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Andrew Savchenko <bircoph@gentoo.org> wrote:
>
> That's why kernel makes sure that no floating point instructions
> sneaks in using CFLAGS, you may see a lot of -mno-${intrucion_set}
> flags when running make -V.

So it should be sufficient that the kernel does not use "float"
or "double", shouldn't it?
I can hardly imagine that otherwise the compiler converts integer
or pointer arithmetic into floating point arithmetics, or is
this really the case for certain flags?  If yes, why should these
flags *ever* be useful?
I mean: The context switching happens for non-kernel code as well,
doesn't it?