[llvm-dev] RFC: Improving license & patent issues in the LLVM community

[David Chisnall via llvm-dev]

On 21 Oct 2015, at 06:15, Chris Lattner <clattner at apple.com> wrote:
> 
> - My understanding is that “GPL2-and-not-later” projects are extremely rare.  Apache 2 is compatible with GPL3 code, and the FSF recommends use of Apache 2 for permissively licensed code (because they see the patent protection as being valuable).  Is there a specific set of affected GPL2-only code that we should consider?  Note that it will still be fine to *compile* GPL2 with Clang for example, it is only linking LLVM code into a GPL2-only app that would become a problem.

It occurred to me that there is one obvious project in this category: QEMU.  It currently uses its own code generator (TCG, BSD licensed) and is GPLv2.  There have been two attempts to adapt it to use LLVM.  There is still some interest from a few people in using LLVM as a second-tier JIT for very hot code paths.  An Apache 2 license would prevent this.

David