[mythtv] Compiling SVN with --arch/--enable-proc-opt (athlon64 CPU w/32bit Fedora)

[Darius Hardy]

Nick wrote:
> Do I get any benefit (and conversely expect any problems) when using
> the configure options '-arch=' and '--enable-proc-opt' when using an
> athlon64 processor with a 32-bit x86 Fedora kernel?
>
You may or may not get benefits from basic athlon optimisations, but 
don't expect anything extra from having an athlon64 running a 32bit 
kernel. Only a 64-bit kernel can make use of the extra 
registers/instructions, under a 32-bit kernel the athlon64 looses its 
64-bit status and it becomes a plain 32-bit processor - albeit with the 
better memory performance.

> When I run configure on SVN (just checked with 11063) without CPU
> options, the CPU was identified as 'x86 (athlon)' with MMX support and
> not as an athlon64. Is this the correct behaviour for detection of a
> 64bit CPU when running on a 32-bit OS or should it detect the \actual\
> CPU?
>
Yes, as that is what it is in 32-bit mode.

-- 
   Darius,
     She who travels light, forgot something.