What CFLAGS should i use?

[lea0014]

Hi there, i'm installing a new box with an AMD FX-6300 processor. Of course, im following the handbook to install the system, but when i have to set the CFLAGS variable, the handbook is not handy at all. So, as far i could see, -march=native is what should i take.
Here comes the deal; i want to run a distcc service at the FX system, and the wiki says:

[BradN]

I believe distcc uses the target system's -march setting when doing remote compile. So, it is okay to use -march=native on the big machine, but you cannot use it on the smaller target machines (assuming lesser instruction set) as that would tell distcc to build binaries with instructions they cannot use (since it is gcc itself deciding what 'native' means, not portage).

If you do "man gcc" you will find the possible choices for -march= on x86 somewhere around line 9000 or so.

[Hu]

Last time I checked, distcc uses the source system's -march setting when using -march=native by way of refusing to distribute the work to remote nodes if the arguments include -march=native.

[Ant P.]

Here's a script I have that outputs the actual flags -march=native expands to; I use this for distcc on my own machines:

[CrUpf]

As the FX-6300 is a Piledriver cpu, and Piledriver is based on Bulldozer, I would suggest something like:
CFLAGS="-O2 -march=bdver1 -mtune=bdver1"

See here:
http://en.wikipedia.org/wiki/Piledriver_%28microarchitecture%29
http://en.wikipedia.org/wiki/Bulldozer_%28microarchitecture%29

http://gcc.gnu.org/gcc-4.6/changes.html

[Schnulli]

you shouldnt use march=native with gcc 4.3 because its only supported above gcc >4.6 its dangerous then .....