Informations about gcc optimization

Simon Comeau Martel martelsc at
Fri Oct 11 13:57:44 PDT 2002

I am running LFS 3.3 and I'll rebuild my system this weekend following the LFS CVS book.  When I built my current system, I didn't use any optimization at all.  But this time, I want to.  But I am not sure what I should use...  My processor is a Celeron 500 MHz.

Should I use something like

CFLAGS="-O3 -s -march=i686" OR
CFLAGS="-O3 -s -march=pentium???"

Does adding the -mcpu option is of any use?  Most of the time, I saw both of them, but from the GCC site: "Moreover, specifying -march=cpu-type implies -mcpu=cpu-type"

If the pentium choice is "better", witch one fit my CPU?

pentium, pentium-mmx, pentiumpro, pentium2, pentium3 ??

Should I add someting else?

(I know that I have to do the same thing with CXXFLAGS)
Unsubscribe: send email to listar at
and put 'unsubscribe lfs-support' in the subject header of the message

More information about the lfs-support mailing list