Compiler Options

Niclas Zeising lothrandil at
Fri Nov 10 22:17:14 UTC 2006

Jason C. Wells wrote:
> I have set CPUTYPE=p3 in make.conf.  When I compile my kernel I see 
> -march=pentium3 as I expect.  I also see -mno-mmx and -mno-sse are set 
> which I do not expect given that -march=pentium3 is used.  I presume 
> that I want MMX and SSE since my processor supports it.  What options do 
> I set and where do I set them to get a kernel properly tuned for pentium3?
> Thanks,
> Jason C. Wells

If i recall correctly, instructions taking advantage of sse, mmx etc. 
are purposefully disabled in the kernel via the mentioned options. I can 
not at the moment recall why though.
Ordinary userland applications and ports are usually compiled to take 
advantage of those instructions if the CPU supports them.


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