I installed ccache and found that the symlinks for the powerpc64le and ppc64le compilers did not exist. This makes it difficult to utilize ccache when using those cross compilers. Pull request started here: https://src.fedoraproject.org/rpms/ccache/pull-request/1
ccache-3.4.2-4.fc29 has been submitted as an update to Fedora 29. https://bodhi.fedoraproject.org/updates/FEDORA-2018-80eb575d5e
ccache-3.4.2-4.fc29 has been pushed to the Fedora 29 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-80eb575d5e
For what it's worth, I made a pull request for Fedora 28 here: https://src.fedoraproject.org/rpms/ccache/pull-request/1
Sorry, wrong link: https://src.fedoraproject.org/rpms/ccache/pull-request/2
ccache-3.4.2-4.fc29 has been pushed to the Fedora 29 stable repository. If problems still persist, please make note of it in this bug report.