David Strauss wrote:
I'm not sure that's a problem. The GPL only affects redistribution, not what a person does on his or her own computer. Just ensure the forbidden integration isn't distributed. (If I'm wrong here, I'd like to know.)
The reason I think this is the case is because the GPL code is not distributed with the non-GPL code. It's OK to distribute a C++ program that uses STL, even though there are proprietary STL implementations. It's also OK for me to compile GPL code against a proprietary STL implementation, as long as I don't redistribute the binary. The only distinction left is that some Drupal modules can *only* link to non-GPL code, but that seems to be a dubious place to draw the line. If we draw the line there, applications using Cocoa break the GPL. Applications using parts of the Windows API absent from Wine break the GPL.