I compile a lot of softwares, And I want them optimized for my machine Pentium IV. So..... how do I make sure that everytime I compile the software, it is automatically optimized for Pentium IV.

For example: I compile kmymoney. After typing ./configure, I got this message:
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu
.....................

Is this mean that everytime I compile from sources, the software will recognize my machine. So I dont need to do anything to make sure that softwares compiled from sources are optimized for Pentium IV. Or not every softwares smart like this? Maybe some are stupid that not recognized my machine so that this stupid softwares are compiled for i386?

What should I do? Just make it simple, please..... Should I play with $CFLAGS environment variables???

Add -march=pentium4 to your CFLAGS

Can someone know where I can find a list of all possible values for the arch parameter ?

You can find more info on the -march option by looking at the gcc-info page ('info gcc') and going to node 'i386 and x86-64 Options'.

thank you sir. I have an athlon duron and I have to choose between the various athlon CPU-TYPE now, I will try 'athlon'

<Edit>
FYI..........Quite a few of the Slackware pkgs are optimized for i686, even tho' they may say name-1.2.3-i486-1.tgz...........After looking at the SlackBuild scripts, the standard compiler optimization flags are: -O2 -march=i486 -mcpu=i686....................At least for the newer build scripts that have the name of "<package_name>.SlackBuild". The older build scripts don't seem to use any optimization. or only the -O2 flag. You can see for yourself by either looking in the source directory on a Slack installation CD, or going to a ftp mirror and looking in the source directory.....
</Edit>

The -mcpu flag is the one that will optimize the binary for the named cpu architecture. The -march flag just makes it compatible for a particular cpu architecture. And they both use the same values.......So, to optimize for a particular arch, remember to use the -mcpu flag.......

For example, I have an Athlon 900 and use -march=i586 -mcpu=athlon 'cause I also have an old Compaq desktop with a P100 chip (i586) which I can use them on as well


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Edited to avoid possible misconceptions about the official Slackpacks.

Very usefull features, gcc rocks... and also linuxquestions.org, thank you for clear up this point.

well

i learned something new today - nice - thanx