version

bwa-mem3 version prints the release version, the build’s compiled-in SIMD floor, the SIMD tier resolved at runtime, and (when mimalloc is compiled in) the mimalloc version. It is the canonical way to confirm which build is on PATH, what host class it requires, and what kernel path it will dispatch to.

bwa-mem3 version always exits 0 — even on a host below the build’s SIMD floor — so operators can introspect a binary on a host that cannot actually run alignment. bwa-mem3 <subcommand> --help and -h share the same property.

Synopsis

mimalloc 3.3.0
v<MAJOR.MINOR>-<N>-g<COMMIT>

Common usage

Confirm the installed version, SIMD floor, and resolved tier:

./bwa-mem3 version

A typical run on an AVX-512BW host with the default BASELINE_ARCH=avx2 build prints (mimalloc line on stderr, the rest on stdout — order in a merged stream is not guaranteed):

v0.2.0-12-gabcdef1
SIMD floor: avx2 (x86-64-v3, Haswell 2013+); kernels: sse41 sse42 avx avx2 avx512bw
SIMD runtime: avx512bw (BWAMEM3_FORCE_TIER unset)
mimalloc 3.3.0

• version line — bwa-mem3’s release string, derived from git describe at build time and stored as PACKAGE_VERSION in the binary. When building from a tarball without git history, the fallback value is set via FG_LABS_VERSION_FALLBACK at compile time.
• SIMD floor: — the compile-time minimum the binary requires. Set by BASELINE_ARCH (default avx2) and listed alongside the per-tier kernel set the binary carries.
• SIMD runtime: — the tier resolved at startup by __builtin_cpu_supports (or BWAMEM3_FORCE_TIER if set in the environment). On arm64 this is always neon.
• mimalloc line — present only when USE_MIMALLOC=1 (the default).

On a host below the SIMD floor, version also writes a [W::bwa-mem3] warning on stderr identifying the gap (and the alignment subcommands will refuse to run with exit code 2 — see Host requirements for the exit-2 message format and rebuild instructions).

Notes / Gotchas

Tip — version | grep is safe in CI

The version, SIMD floor:, and SIMD runtime: lines all go to stdout; the mimalloc line and any host-below-floor warning go to stderr. So bwa-mem3 version | grep '^SIMD' works in CI scripts even on hosts that cannot run alignment. Use 2>/dev/null to suppress the mimalloc and warning lines if you want stdout only.

Tip — No mimalloc line means USE_MIMALLOC=0

If no mimalloc line appears, the binary was built without the bundled allocator (make USE_MIMALLOC=0). See User Guide — Memory allocator (mimalloc) for when this is appropriate.

See also: User Guide — Memory allocator (mimalloc) · Developer Guide — Release process · Getting Started — Installation · What’s Different — Build & infrastructure