Re: Why not build kernel with -O3

From: Pengfei Yuan
Date: Wed Apr 08 2015 - 09:19:37 EST

2015-04-08 20:06 GMT+08:00 Austin S Hemmelgarn <ahferroin7@xxxxxxxxx>:
> I can't remember any off the top of my head, but it does say explicitly in
> the GCC manual to be careful with -O3. IIRC, most of the issues relate to
> -O3 enabling -ffast-math (which tends to really mess with code that expects
> strict IEEE 754 compliance), so it may not be as much of an issue for kernel
> code. You might look into some of the projects that use -O3 by default (I
> think most of the Mozilla so0ftware does these days, and I know that there
> are others, I just can't remember what right now).

I am afraid you are talking about -Ofast, not -O3.

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