ZJIT can now inline GC allocations

#​815 — September 3, 2026 Read on the Web Ruby Weekly ZJIT 🤝 GC: Inlining GC Fastpath in ZJIT — JIT compilation first came to CRuby eight years ago, but the garbage collector has remained opaque to CRuby's JITs, with every allocation requiring a function call. Now, ZJIT can inline allocations, yielding a notable performance boost. Fingers crossed for Ruby 4.1! Peter Zhu 💡 On Bluesky, Benoit Daloze noted that TruffleRuby has been doing this for a decade , one of many reasons it's such a f...