See: https://www.gnu.org/licenses/gpl-3.0.html#howto
Run:
$ git grep -l 'Foundation; either version 3' \
| xargs sed -i '/Foundation; either version 3/ s/n; e/n, e/'
* All files using GPLv3: Adjust via the above command.
* tests/test-thrd_create.c: New file, based on
tests/test-thread_create.c.
* tests/test-thrd_current.c: New file, based on
tests/test-thread_self.c.
* modules/thrd-tests: New file.