Why llvm-gcc/g++ does not support the 64-bit SPARC ABI (-m64)

My application is 64bit running on Solaris 10 with Sparc. I’d like to use llvm-gcc/g++ to compile it to make it run faster. But in the Release Notes of the latest LLVM release, it says

Known problems with the SPARC back-end

* The SPARC backend only supports the 32-bit SPARC ABI (-m32); it does not support the 64-bit SPARC ABI (-m64).

Why it doesn’t support 64bit on sparc?

Thanks!

I believe it's because no-one has bothered to implement it. :slight_smile: Few of
us have Sparc machines to develop and test on. If you're willing to
give it a try, we would appreciate any patches you may have!

-bw