[Devel] Compiler CPU optimizations

[Dan Pascu]

For as long as I remember compiling openser, always used -mtune=athlon 
(with gcc-3.x) and now it's using -mtune=athlon64 (with gcc-4.x), even 
though I always compiled it on pentium4 CPUs. Now according to the gcc 
manual, -mtune only seems to make a difference for ARM processors, still 
if the next version of gcc would include specific optimizations for 
athlon64 I guess my binary will have troubles to run on an intel pentium4 
32 bit CPU

From what I gather from Makefile.defs, if gcc is 4.x then CPU is set 
automatically to athlon64 without trying to actually detect the CPU, 
which can be a problem. IMO, if the CPU cannot be/is not detected, then 
the most generic CPU type for that class should be used. athlon64 is 
anything but generic.

-- 
Dan