The exact same situation happened with Objective C and GCC. In that case, the Objective C frontend was released as free software.
Apple don't own LLVM at all - they hired Chris Lattner who was one of the original directors of the project when it started at the University of Illinois.
> should have been copylefted to begin with
Why? To prevent the vast majority of companies with the money to actually support and grow such a project the way LLVM has, from doing so?
You mean the ones that haven't provided LLVM with changes for the compilers they are selling?
I could not care less about having the changes to their compilers, and I would even dislike it if LLVM's license required them to do so if that meant they wouldn't touch LLVM in the first place -- in which case we wouldn't get all these core LLVM improvements.
> Why? To prevent the vast majority of companies with the money to actually support and grow such a project the way LLVM has, from doing so?
No, because the freedom of new languages in LLVM would be guarenteed.
Again, you can of course have the opinion that this is not important, or not as important as the success of LLVM, but that's your decision.
No, the GPL does not work that way.
If LLVM was GPL it wouldn't make any difference. LLVM is modular. You can write a front end that generates LLVM IR, then pass that LLVM IR file to LLVM to be compiled. It would be no different then a program that generates bitmaps and then passes them to another program to be jpeg encoded. The licence of the jpeg encoder doesn't affect the licence of your bitmap generating code.
This is why GCC is not modular.