As of September 2023 (llvmorg-18.1.0-rc1) /usr/include/c++/v1/__config no longer includes <sys/endian.h>, because both Clang and GCC always define __BYTE_ORDER__ macro. This had accidentally revealed a problem in Kanzi data compressor which was including <machine/endian.h> to no avail. Replace it with <sys/endian.h> to obtain bswap??() definitions. Reported by: pkg-fallout PR: 285285 LLVM commit: https://github.com/llvm/llvm-project/commit/0a97720