gobject-introspection has two licenses; one for the typelib library,
and one for the tools.

* The typelib libraries (girepository/) are licensed under the LGPLv2+.
  See the file COPYING.LGPL.

* The remaining code is GPLv2+ compatible (see the file COPYING.GPL) and
  consists of a mix of GPLv2+, LGPLv2+ and MIT. See the license headers in
  each file for details.

In general where applicable files should have headers denoting their license
status; if they do not, please file a bug at
https://gitlab.gnome.org/GNOME/gobject-introspection/issues.