Gentoo Wiki


This is a current work in progress.



Compiler Settings

The compiler settings are the following three variables: CFLAGS, CHOST and CXXFLAGS. The only one that you will want to change is the CFLAGS.

This is where you change adjust various compiler settings that will be applied whenever software is compiled. And while explaining all of these is beyond the scope of this document, the one important one that will be covered is the march setting.

This setting tells the GCC compiler which CPU you are using at it optimizes the code it generates for the abilities of that processor. This is a setting that you will want to specify. You can look up the CFLAGS that are appropriate for your CPU on the Safe Cflags page.

Warning: If you specify a newer generation (or wrong family) processor than you actually have, you might experience weird issues and/or non-functional programs.

USE Flags

USE flags are an important part of Gentoo and the packaging system is uses Portage. These flags determine what functionality will get installed when you install other packages. For more information on what USE flags actually are, please refer to the USE flags page.

Processor Specific USE Flags

There are several USE flags you can take advantage of depending on the capabilities of your processor. You can check the abilities of your processor by doing cat /proc/cpuinfo and looking at what is in the flags it returns to see if any of these USE flags are relevant for your CPU.


The following are some example sets of USE flags from various Gentoo machines with different purposes. This should help give you some idea of what things you may wish to include.


Here is an example of the USE flags you might use if your Gentoo install was going to be primarily running MythTV.

File: /etc/make.conf
  USE="session pcre posix nptl nptlonly xvid mpeg flac threads lirc alsa X hal tiff xvid mysql -gtk -gnome -kde qt dvd a52 usb win32codecs aac flac ogg samba vorbis ftp xine mjpeg transcode"

VMWare Gentoo Install

This is an example of USE flags that you might choose to use if you want a basic Gentoo workstation running inside of VMWare.

File: /etc/make.conf
  USE="X -gnome kde alsa samba jpeg"

Xorg Settings

This section is only relevant if you intend to install the Xorg windowing system.

Video Card

Input Devices

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Last modified: Fri, 22 Jun 2007 15:51:00 +0000 Hits: 3,802