SPDX license expressions

[dg0yt]

I try to understand the licensing to update the summary in the vcpkg port, and I find it somewhat confusing.

The README has https://github.com/axboe/liburing/blob/7b3245583069bd481190c9da18f22e9fc8c3a805/README#L101-L104

The files have

grep -R -h SPDX buildtrees/liburing/src/buring-2.6-5b246c73a3.clean/ | sort -u
/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */
.\" SPDX-License-Identifier: LGPL-2.0-or-later
/* SPDX-License-Identifier: MIT */
/* SPDX-License-Identifier: MIT */
// SPDX-License-Identifier: MIT

i.e. the claimed "dual licensed LGPL and MIT" isn't reflected in any header. There is LGPL-2.0-or-later but COPYING is LGPL 2.1.

"GPL-2.0" is a deprecated identifier in SPDX, suffering from the same deficit as the verbal "LGPL" (which even lacks a version, but there is COPYING): It is not clear if means <version>-only or <version>-or-later. Cf. https://www.gnu.org/licenses/identify-licenses-clearly.html

For reference, Debian has https://tracker.debian.org/media/packages/libu/liburing/copyright-2.6-1.

[dg0yt]

@axboe axboe closed this as completed Oct 2, 2024

Is there a summary how this was completed?