Overall license

The license for ccache as a whole is as follows:

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; either version 3 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 51 Franklin
Street, Fifth Floor, Boston, MA 02110-1301 USA

The full license text can be found in GPL-3.0.txt and at https://www.gnu.org/licenses/gpl-3.0.html.

Ccache is a collective work with contributions from many people, listed in AUTHORS.adoc and at https://ccache.dev/credits.html. Subsequent additions by contributing authors are implicitly licensed to the public under the same terms (GNU GPL version 3 or later), but the contributing authors retain copyrights on their portions of the work.

The copyright for ccache as a whole is as follows:

Copyright (C) 2002-2007 Andrew Tridgell
Copyright (C) 2009-2021 Joel Rosdahl and other contributors

Files derived from other sources

The ccache distribution contain some files from other sources and some have been modified for use in ccache. These files all carry attribution notices, and may qualify as “separate and independent works in themselves” for purposes of the GPL: that is, if separated from the ccache sources, they may be usable under less restrictive terms.

src/third_party/base32hex.*

This base32hex implementation comes from https://github.com/pmconrad/tinydnssec.

(C) 2012 Peter Conrad <conrad@quisquis.de>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License version 3 as
published by the Free Software Foundation.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

src/third_party/blake3/blake3_*

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src/third_party/xxh*

xxHash - Extremely Fast Hash algorithm. Copied from xxHash v0.8.0 downloaded from https://github.com/Cyan4973/xxHash/releases.

Copyright (c) 2012-2020 Yann Collet
All rights reserved.

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