Short version for non-lawyers:

The Rust Project is dual-licensed under Apache 2.0 and MIT
terms.


Longer version:

Copyrights in the Rust project are retained by their contributors. No
copyright assignment is required to contribute to the Rust project.

Some files include explicit copyright notices and/or license notices.
For full authorship information, see the version control history or
https://thanks.rust-lang.org

Except as otherwise noted (below and/or in individual files), Rust is
licensed under the Apache License, Version 2.0 <LICENSE-APACHE> or
<http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
<LICENSE-MIT> or <http://opensource.org/licenses/MIT>, at your option.


The Rust Project includes packages written by third parties.
The following third party packages are included, and carry
their own copyright notices and license terms:

* LLVM, located in src/llvm-project, is licensed under the following
  terms.

    ==============================================================================
    The LLVM Project is under the Apache License v2.0 with LLVM Exceptions:
    ==============================================================================

                                    Apache License
                              Version 2.0, January 2004
                            http://www.apache.org/licenses/

        TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

        1. Definitions.

          "License" shall mean the terms and conditions for use, reproduction,
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          You may add Your own copyright statement to Your modifications and
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        5. Submission of Contributions. Unless You explicitly state otherwise,
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        END OF TERMS AND CONDITIONS

        APPENDIX: How to apply the Apache License to your work.

          To apply the Apache License to your work, attach the following
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        Copyright [yyyy] [name of copyright owner]

        Licensed under the Apache License, Version 2.0 (the "License");
        you may not use this file except in compliance with the License.
        You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

        Unless required by applicable law or agreed to in writing, software
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        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
        See the License for the specific language governing permissions and
        limitations under the License.


    ---- LLVM Exceptions to the Apache 2.0 License ----

    As an exception, if, as a result of your compiling your source code, portions
    of this Software are embedded into an Object form of such source code, you
    may redistribute such embedded portions in such Object form without complying
    with the conditions of Sections 4(a), 4(b) and 4(d) of the License.

    In addition, if you combine or link compiled forms of this Software with
    software that is licensed under the GPLv2 ("Combined Software") and if a
    court of competent jurisdiction determines that the patent provision (Section
    3), the indemnity provision (Section 9) or other Section of the License
    conflicts with the conditions of the GPLv2, you may retroactively and
    prospectively choose to deem waived or otherwise exclude such Section(s) of
    the License, but only in their entirety and only with respect to the Combined
    Software.

    ==============================================================================
    Software from third parties included in the LLVM Project:
    ==============================================================================
    The LLVM Project contains third party software which is under different license
    terms. All such code will be identified clearly using at least one of two
    mechanisms:
    1) It will be in a separate directory tree with its own `LICENSE.txt` or
      `LICENSE` file at the top containing the specific license and restrictions
      which apply to that software, or
    2) It will contain specific license and restriction terms at the top of every
      file.

    ==============================================================================
    Legacy LLVM License (https://llvm.org/docs/DeveloperPolicy.html#legacy):
    ==============================================================================
    University of Illinois/NCSA
    Open Source License

    Copyright (c) 2003-2019 University of Illinois at Urbana-Champaign.
    All rights reserved.

    Developed by:

        LLVM Team

        University of Illinois at Urbana-Champaign

        http://llvm.org

    Permission is hereby granted, free of charge, to any person obtaining a copy of
    this software and associated documentation files (the "Software"), to deal with
    the Software without restriction, including without limitation the rights to
    use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
    of the Software, and to permit persons to whom the Software is furnished to do
    so, subject to the following conditions:

        * Redistributions of source code must retain the above copyright notice,
          this list of conditions and the following disclaimers.

        * Redistributions in binary form must reproduce the above copyright notice,
          this list of conditions and the following disclaimers in the
          documentation and/or other materials provided with the distribution.

        * Neither the names of the LLVM Team, University of Illinois at
          Urbana-Champaign, nor the names of its contributors may be used to
          endorse or promote products derived from this Software without specific
          prior written permission.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
    FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
    SOFTWARE.

* Portions of the FFI code for interacting with the native ABI
  is derived from the Clay programming language, which carries
  the following license.

    Copyright (C) 2008-2010 Tachyon Technologies.
    All rights reserved.

    Redistribution and use in source and binary forms, with
    or without modification, are permitted provided that the
    following conditions are met:

    1. Redistributions of source code must retain the above
       copyright notice, this list of conditions and the
       following disclaimer.

    2. Redistributions in binary form must reproduce the
       above copyright notice, this list of conditions and
       the following disclaimer in the documentation and/or
       other materials provided with the distribution.

    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
    PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
    DEVELOPERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
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    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
    USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
    USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
    OF SUCH DAMAGE.

* Portions of internationalization code use code or data from Unicode, which
  carry the following license:

      UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE

    See Terms of Use <https://www.unicode.org/copyright.html>
    for definitions of Unicode Inc.’s Data Files and Software.

    NOTICE TO USER: Carefully read the following legal agreement.
    BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
    DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
    YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
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    IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
    THE DATA FILES OR SOFTWARE.

    COPYRIGHT AND PERMISSION NOTICE

    Copyright © 1991-2022 Unicode, Inc. All rights reserved.
    Distributed under the Terms of Use in https://www.unicode.org/copyright.html.

    Permission is hereby granted, free of charge, to any person obtaining
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    (the "Data Files") or Unicode software and any associated documentation
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    (a) this copyright and permission notice appear with all copies
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    (b) this copyright and permission notice appear in associated
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    THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
    ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
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    IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
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    Except as contained in this notice, the name of a copyright holder
    shall not be used in advertising or otherwise to promote the sale,
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