I have updated the license for MACRO SPITBOL from ‘GPL v3 or later’ to ‘GPL v2 or later’.
This was motivated by a conversation with Rob Landley, who first made me aware that that GPLv2 and GPLv3 are not compatible.
An explanation of why this is so can be found in the following post by Richard Stallman, Why Upgrade to GPL Version 3.
The result of this modest — indeed only the change from ’3′ to ’2′ in the license version — is that people wishing to use SPITBOL can now incorporate it in code licensed under any of the following combinations:
- GPL v2
- GPL v2 or later
- GPL v3
- GPL v3 or later
Contributions will only be accepted under the new terms — gplv2 or later — to give those who choose to use the code more freedom in their choice of license.