Phoronix's year-end 2025 benchmarking analysis, published today, indicates significant performance improvements for Linux 6.19 kernels compiled with LLVM Clang 21, particularly when Link-Time Optimization (LTO) is enabled. The benchmarks compared kernels built using the latest stable GCC 15 against Clang 21, noting that "meaningful performance benefits" were observed with the Clang + LTO combination. This latest evaluation by Phoronix follows several years of maturation for Clang-built Linux kernels, driven by upstream enhancements in both the LLVM/Clang toolchain and the Linux kernel itself, validating its growing viability for optimized system performance. The findings suggest that compiling the kernel with Clang and LTO can lead to a more performant system.