XZ 5.8 is out today as the first notable feature release since last year's malicious backdoor in XZ 5.6 inserted by a then-co-maintainer of the project. XZ 5.6.2 was out last May while XZ 5.8.0 is now stable today for bringing new features to this lossless data compressor project.

With liblzma when built for x86 or x86_64 architectures, SSE2 intrinsics are now attempted instead of memcpy() for the LZMA/LZMA2 decoder. This SSE2 intrinsic use can yield up to 5% reduced decompression times. Or if building against the musl C library, these SSE2 intrinsics can lead to an over 15% time reduction for highly compressed files.

In addition to the XZ 5.8 SSE2 intrinsics use for liblzma, there are also CMake build system updates, language translation updates, improved LZMA/LZMA2 encoder performance for 64-bit POWER and RISC-V, rewriting of the x86_64 E2K CLMUL CRC code, and other optimizations.

The XZ 5.8 update was managed by Lasse Collin and can be downloaded from the official XZ project site .