HowTo: Using ccache on FreeBSD

ccache is a compiler cache. It speeds up re-compilation of C/C++ code by caching previous compiles and detecting when the same compile is being done again.

The following is a step by step guide to how to enable and use ccache on FreeBSD 7.1:

1. % su
2. # cd /usr/ports/devel/ccache
3. # make install clean
4. # vim /etc/make.conf

.if (!empty(.CURDIR:M/usr/src*) || !empty(.CURDIR:M/usr/obj*)) && !defined(NOCCACHE)
CC=/usr/local/libexec/ccache/world-cc
CXX=/usr/local/libexec/ccache/world-c++
.endif

Basically we've started by installing ccache (steps 1 through 3) and proceeded by editing /etc/make.conf as to enable ccache on builds.

Now we need to update the environment.

If you are using csh/tcsh shell add the following to /root/.cshrc:

setenv PATH /usr/local/libexec/ccache:$PATH
setenv CCACHE_PATH /usr/bin:/usr/local/bin
setenv CCACHE_DIR /var/tmp/ccache
setenv CCACHE_LOGFILE /var/log/ccache.log

If you are using zsh add the following to your /root/.zshrc file:

export PATH=/usr/local/libexec/ccache:$PATH
export CCACHE_PATH=/usr/bin:/usr/local/bin
export CCACHE_DIR=/var/tmp/ccache
export CCACHE_LOGFILE=/var/log/ccache.log

After updating the dotfiles we update the environment. Users of csh/tcsh shells can update by:

• # source /root/.cshrc

Anyone using zsh can update the environment by running the following command:

• # source /root/.zshrc

And that's it: ccache is installed and the environment is updated. Your next build will be performed with ccache enabled.

To display statistics summary:

• % ccache -s

To zero statistics:

• % ccache -z

To check out the help file for a list of ccache options:

• % ccache -h

If you come across a port that fails to build, disable ccache and try again:

• # make NOCCACHE=yes install clean

You can find more information regarding ccache through:

• % man ccache
• % ccache -h
  
• % less /ur/local/share/doc/ccache/ccache-howto-freebsd.txt
• % links /ur/local/share/doc/ccache/index.html
• http://forums.freebsd.org/showthread.php?t=174