DMD Backend Long-term

[bearophile]

Robert Jacques:
> The patent seems to be Borlands's:
> USPTO patent #5,628,016 Patent held by Borland on compiler support for SEH.
>  From a Wine wiki page: http://wiki.winehq.org/CompilerExceptionSupport
> 
> It does seem to expire on June 15, 2014, though and I assume DigitalMars  
> has a license, so a LLVM fork is not unreasonable.

On Windows G++ supports exceptions. I have two questions:
1) Do you know how they do this? Do they have a license? If they have a licence why don't LLVM people too have it?
2) Why isn't LLVM just copying that part of the GCC code? If a true copy is not possible, why aren't copying the code with enough cosmetic changes? (A good amount of time ago I did believe that the main purpose of the Open Source idea was to copy source code between projects, to avoid reinventing things. I was so wrong.)

Bye,
bearophile