Following the instructions outlined in Working with Gentoo, Portage Features, Caching compilations (see URL) does not fully enable caching. The CCACHE_DIR environment variable being set to "/var/tmp/ccache/" cures this problem. Reproducible: Always Steps to Reproduce: 1. Follow ccache install instructions 2. emerge something 3. Check ccache -s shows no usage 4. echo CCACHE_DIR="/var/tmp/ccache" >> /etc/env.d/99local 5. env-update 6. emerge something 7. ccache -s now shows usage
> 3. Check ccache -s shows no usage Uhm, no... it does cache, your command is incorrect. It should be 'CCACHE_DIR=/var/tmp/ccache ccache -s' No environment variable is however needed for the caching to work during emerge.