LLVM 17 is bringing support for new Intel ISA extensions, initial NVIDIA CUDA Fortran support, RISC-V Vector Crypto Extension ISA support, a tuned AMD Zen 4 scheduler model, exposing -std=c++23 rather than limited to the -std=c++2b form, new AMDGPU back-end additions, and a variety of other improvements. LLVM 17 so far has seen nearly 38,000 commits over LLVM 16.
Clang 17 also has improved -O0 code generation, more C++20 and C++23 features wired up, some early bits of C++2C support as well as introducing those targeting flags, more C2x feature bits, and enhanced Clang diagnostics.
LLVM 17.0-rc1 sources are available for download from GitHub . LLVM will see bi-weekly release candidates until the LLVM 17.0 stable release is ready in the coming weeks.