flags for GCC 332

[Rakotomandimby Mihamina]

Hi all,
I'm using Linux slackware 9.1 and i use it as a web server .
I would like to recompile some softwares because they where compiled with
486 -march option and i use an "AMD Duron 800 Mhz" CPU on one box and on
another one i use an "AMD T-Bird 2200+"

Wich flags do you advice me to use for each of them ? as far as i searched,
i got theses conclusions :

*for the AMD Duron 800 Mhz :
CFLAGS=-O3 -mcpu=athlon -fomit-frame-pointer
or 
CFLAGS=-O3 -march=athlon -fomit-frame-pointer
What flags for C++ (g++) ? 
What's the associated environement variable ? CXXFLAGS ?

*for the AMD T-Bird 2200+ :
CFLAGS=-O3 -mcpu=athlon-tbird -fomit-frame-pointer
Idem , what flags for g++ ? what environment variables ?

I heard "-march" was deprecated so that i should use "-mpcu" .Is that
right ?

To have a minimum of significant perfs improve , some of my friends adviced
me to recompile binutils , then glibc (2.3.2) , then gcc (3.3.2) , then
re-binutils , then re-glibc , then re-gcc . If i have time i'm going to
recompile my all system ... no worth ? what sould i recopiled at least ?

I guess that my t-bird CPU is more supported on the latest version of
GCC ... am i right ? :-) is that the same for my Duron ?


PS: i'm neither a C nor C++ fluent user, i'm more an electric student than a
computer student, so try to have the most simple explanation possible
please, so that i wont annoy you for a too much long time :-)
-- 
Rakotomandimby Mihamina Andrianifaharana
Tel : + 33 2 38 76 43 65
http://stko.dyndns.info/