LLVM/Clang 18.1 Released With Intel AVX10.1 Work, Adds Clearwater Forest & Panther Lake

Out today is the big LLVM/Clang 18.1 release. Due to shifting to a new versioning scheme like GCC, today's LLVM 18.1 release is the first major stable release in the new series for what previously would have been called LLVM 18.0.

LLVM/Clang 18.1 is the newest six-month feature update to this open-source compiler stack. There's new Intel ISA support as well as new targets for Intel CPUs being released in the future, continued enablement of new C++23 features, more C23 enablement, and a variety of other great additions.

LLVM 18 release highlights include:

- ISA support for Intel AVX10.1-256 and AVX10.1-512.

- Intel Panther Lake and Clearwater Forest targets are now added with -march=pantherlake and -march=clearwaterforest.

- The "-mapxf" switch is now supported as part of the ongoing Intel Advanced Performance Extensions (APX) enablement.

- Various new RISC-V instructions are supported. The SiFive P670 target is also now supported.

- Support for Arm Cortex A520, A720, and X4 CPUs. The Arm Cortex-M52 CPU is also now supported.

- LLVM 18 on LoongArch now supports LSX 128-bit and LASX 256-bit SIMD with new intrinsics. LoongArch on LLVM also has initial support for auto vectorization and linker relaxation.

Clang 18 release highlights include:

- Continued eanblement on C++20 and C++23 features. There's also some early feature work on C++2c.

- Clang now honors the -std=c23 and -std=gnu23 options for C23 language support. Plus various additional C23 features are now implemented.

- Support for the Intel AVX10.1 ISA as well as Intel additions for USER_MSR.

- Intel Panther Lake and Clearwater Forest targets are now added with -march=pantherlake and -march=clearwaterforest.

- The "-fopenacc" option is now honored as part of the effort upstreaming OpenACC support in Clang. THe OpenACC upstreaming effort is still ongoing.

- Various changes to enhance the interoperability / semantics of GCC.

- Many improvements to Clang's diagnostics.

- Alpha support for ARM SVE2.1 intrinsics.

- Various new experimental checkers for Clang's static analyzer.

- Intel OpenMP kernel language support.

- Quite a lot of bug fixes.

Those wanting to download the LLVM 18.1 compiler stack can do so via GitHub.