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194 changes: 154 additions & 40 deletions LICENSE
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GNU LESSER GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

VCFloat: A Unified Coq Framework for Verifying C Programs with
Floating-Point Computations. Application to SAR Backprojection.

Copyright (C) 2015 Reservoir Labs Inc.
Copyright (C) 2021-22 Andrew W. Appel and Ariel Kellison

This software and each of its files are free software. You can
redistribute them and/or modify them under the terms of the GNU
General Public License as published by the Free Software Foundation,
either version 3 of the License (GNU GPL v3), or (at your option) any
later version. A verbatim copy of the GNU GPL v3 is included in
gpl-3.0.txt.

This software 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 GPL
v3 (and CeCILL-C for patches/interval.patch) for more details.

This work was sponsored in part by DARPA MTO as part of the Power
Efficiency Revolution for Embedded Computing Technologies (PERFECT)
program (issued by DARPA/CMO under Contract No: HR0011-12-C-0123). The
views and conclusions contained in this work are those of the authors
and should not be interpreted as representing the official policies,
either expressly or implied, of the DARPA or the
U.S. Government. Distribution Statement "A" (Approved for Public
Release, Distribution Unlimited.)


If you are using or modifying VCFloat in your work, please consider
citing the following paper:

Tahina Ramananandro, Paul Mountcastle, Benoit Meister and Richard
Lethin.
A Unified Coq Framework for Verifying C Programs with Floating-Point
Computations.
In CPP (5th ACM/SIGPLAN conference on Certified Programs and Proofs)
2016.

VCFloat requires uses third-party libraries listed in ACKS, which
have various licenses of their own.
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.

This version of the GNU Lesser General Public License incorporates the terms
and conditions of version 3 of the GNU General Public License, supplemented
by the additional permissions listed below.

0. Additional Definitions.

As used herein, “this License” refers to version 3 of the GNU Lesser General
Public License, and the “GNU GPL” refers to version 3 of the
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68 changes: 68 additions & 0 deletions OLD_LICENSE
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How VCFloat became LGPL licensed instead of GPL licensed: a History

VCFloat, a Coq Framework for verifying floating-point computations,
was originally developed by researchers at Reservoir Labs Inc.
It was copyright (C) 2015 Reservoir Labs Inc., made open-source
under the Gnu Public License (GPL), and published in a github repo.

In 2021 and 2022, Andrew Appel and Ariel Kellison made contributions
to the github repo, which were also (therefore) GPL Licensed.

In 2022, Reservoir Labs Inc. was acquired by Qualcomm. Qualcomm determined
that this was not an open-source project that they wanted to continue
to maintain. Since Andrew Appel was interested in maintaining and improving
VCFloat, Qualcomm generously decided to transfer all its copyright ownership
in VCFloat to Andrew Appel, which was done by contract in June 2022.

The maintainers of a GPL-licensed repository cannot simply change the license
to some other license, even LGPL, unless every one of the copyright owners agrees.
In July 2022, "every one of the copyright owners" was Andrew Appel and Ariel Kellison.
On 10 July 2022, those owners hereby license their copyrighted software under the LGPL.

We welcome contributions by others to VCFloat, which will continue to be LGPL licensed.

Below, for historical purposes, we reproduce the license agreement as it stood
in June 2022.

--------------OLD, OBSOLETE LICENSE FOLLOWS---------------------------

VCFloat: A Unified Coq Framework for Verifying C Programs with
Floating-Point Computations. Application to SAR Backprojection.

Copyright (C) 2015 Reservoir Labs Inc.
Copyright (C) 2021-22 Andrew W. Appel and Ariel Kellison

This software and each of its files are free software. You can
redistribute them and/or modify them under the terms of the GNU
General Public License as published by the Free Software Foundation,
either version 3 of the License (GNU GPL v3), or (at your option) any
later version. A verbatim copy of the GNU GPL v3 is included in
gpl-3.0.txt.

This software 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 GPL
v3 (and CeCILL-C for patches/interval.patch) for more details.

This work was sponsored in part by DARPA MTO as part of the Power
Efficiency Revolution for Embedded Computing Technologies (PERFECT)
program (issued by DARPA/CMO under Contract No: HR0011-12-C-0123). The
views and conclusions contained in this work are those of the authors
and should not be interpreted as representing the official policies,
either expressly or implied, of the DARPA or the
U.S. Government. Distribution Statement "A" (Approved for Public
Release, Distribution Unlimited.)


If you are using or modifying VCFloat in your work, please consider
citing the following paper:

Tahina Ramananandro, Paul Mountcastle, Benoit Meister and Richard
Lethin.
A Unified Coq Framework for Verifying C Programs with Floating-Point
Computations.
In CPP (5th ACM/SIGPLAN conference on Certified Programs and Proofs)
2016.

VCFloat requires uses third-party libraries listed in ACKS, which
have various licenses of their own.
20 changes: 15 additions & 5 deletions README
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Expand Up @@ -7,12 +7,22 @@ Version 2.0 (2022-3-10) Many improvements, see below.
Copyright (C) 2015 Reservoir Labs Inc.
Copyright (C) 2021-22 Andrew W. Appel and Ariel Kellison.

VCFloat is open-source licensed according to the LGPL (Gnu Lesser General
Public License) version 3 or any later version.

Previously it was licensed differently; see OLD_LICENSE for an explanation.

This software is distributed WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

By making a pull-request to this repo, or by making a direct push, or by contributing
by any other such means, you thereby certify that you have the rights to do
so specified in the Developer Certificate of Origin, https://developercertificate.org/
and you also thereby license your contribution by the LGPL 3.0 and later.

VCFloat 1.0 was implemented 2015 by Tahina Ramananandro et al (see citation below).
VCFloat since 2021 is maintained and extended by Andrew Appel and Ariel Kellison.

VCFloat is distributed under the GNU General Public License, version
3.0 or later. See LICENSE.

For an introduction, read
VCFloat2: Floating-point error analysis in Coq, by Appel & Kellison, 2022,
available as doc/vcfloat2.pdf in this repository.
Expand Down Expand Up @@ -78,8 +88,8 @@ from opam, from the Coq Platform, or (deprecated method) automatically
downloaded from their official sources and built during VCFloat's
building process:

- CompCert 3.10 (from AbsInt's GitHub at
https://github.com/AbsInt/CompCert.git), or from opam
- CompCert 3.10 (from AbsInt's GitHub at https://github.com/AbsInt/CompCert.git),
or from opam (but you don't need CompCert at all if you are using the "ftype" style, see above)

- Ssreflect 1.5 or later, e.g. from opam

Expand Down

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