License Cocktail With GPL In Doom

Rob wrote in to say: "There is an interesting news item on Doomworld about all the different licenses under which the sourceports of Doom are distributed -- at once! According to this article, some source ports use up to three different licenses, among them the GPL. So doesn't this make it GPL'd? But what about the other licenses? Do the authors have to stick to a single license and dispose of code which is covered by another license?"

Comments

No, It doesn't make it GPL'ed

[Lita Juarez]

Section 4 of the GPL states that "You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense or distribute the Program is void, and will automatically terminate your rights under this License". Therefore, incorporating GPL'ed code into something which is non-GPL'ed invalidates the license on the GPL'ed code. Legally, the GPL'ed code must be removed.

The only way around this (that I can see) would be to convince the author of the GPL'ed to give you dispensation to release their code under a different license.

The way I see it, software licenses are like blood groups - different blood groups are incompatible and must be kept separate (or else all sorts of Bad Things happen), and the same is true for licences. To avoid trouble, it is better to make sure all code is released under the same licence. The GPL is by far the most restrictive licence ever conceived in this respect, and rather than giving people the freedom to do whatever they wish with the code, it ends up being a straightjacket to restrict their freedom. I would prefer to see more people releasing their code under the BSD license.