-original message- Subject: Re: [gentoo-user] CFlags for CPU From: Andy Wilkinson <[email protected]> Date: 2011-07-27 21:09
>Another good trick I've found on the forums is to run: > >$ gcc -### -e -v -march=native /usr/include/stdlib.h > >The last line of output will include the various CFLAGS that >-march=native picks. In my case (Phenom II 955): > > "/usr/libexec/gcc/x86_64-pc-linux-gnu/4.4.5/cc1" "-quiet" >"/usr/include/stdlib.h" "-D_FORTIFY_SOURCE=2" *"-march=amdfam10" >"-mcx16" "-msahf" "-mpopcnt"* "--param" "l1-cache-size=64" "--param" >"l1-cache-line-size=64" "--param" "l2-cache-size=512" "-mtune=amdfam10" >"-quiet" "-dumpbase" "stdlib.h" "-auxbase" "stdlib" "-o" >"/tmp/ccR1PlNZ.s" "--output-pch=/usr/include/stdlib.h.gch" > >I typically use -march=native when I don't need to worry about distcc, >or the options from that output that start with "-m". Hey, that's a nice trick! Thanks for re-sharing :) That said, I usually *can't* use -march=native because all my Gentoo systems are virtualized servers, running on top of XenServer, which itself runs on heterogenous server boxes (all Intel). So, I purposefully limit myself to "-march=nocona". (I did raise an explicit point about -march parameter in my Gentoo-Wiki article) Rgds, -- FdS Pandu E Poluan ~ IT Optimizer ~ Sent from Nokia E72-1
