YJIT: Disable static_mut_refs for now

Merged: https://github.com/ruby/ruby/pull/12310

yjit/src/lib.rs

@@ -3,6 +3,17 @@
 #![allow(clippy::too_many_arguments)] // :shrug:
 #![allow(clippy::identity_op)] // Sometimes we do it for style
 
+// TODO(alan): This lint is right -- the way we use `static mut` is UB happy. We have many globals
+// and take `&mut` frequently, sometimes with a method that easily allows calling it twice.
+//
+// All of our globals rely on us running single threaded, which outside of boot-time relies on the
+// VM lock (which signals and waits for all other threads to pause). To fix this properly, we should
+// gather up all the globals into a struct to centralize the safety reasoning. That way we can also
+// check for re-entrance in one place.
+//
+// We're too close to release to do that, though, so disable the lint for now.
+#![allow(static_mut_refs)]
+
 pub mod asm;
 mod backend;
 mod codegen;