minor fixups

Author: Fidget-Spinner

Python/pylifecycle.c

@@ -1721,7 +1721,7 @@ finalize_modules(PyThreadState *tstate)
     PyInterpreterState *interp = tstate->interp;
 
     // Invalidate all executors and turn off JIT:
-    interp->jit = 0;
+    FT_ATOMIC_STORE_UINT8(interp->jit, 0);
     interp->compiling = false;
 #ifdef _Py_TIER2
     _Py_Executors_InvalidateAll(interp, 0);

Tools/jit/_optimizers.py

@@ -562,8 +562,7 @@ def run(self) -> None:
         for _ in range(4):
             self._invert_hot_branches()
             self._remove_redundant_jumps()
-            # FIXME (gh-141594): Breaks LLVM on FT builds
-            # self._remove_unreachable()
+            self._remove_unreachable()
         self._fixup_external_labels()
         self._fixup_constants()
         self.path.write_text(self._body())