diff --git a/naga/src/back/msl/writer.rs b/naga/src/back/msl/writer.rs
index 83d937d486..19e56a8a6e 100644
--- a/naga/src/back/msl/writer.rs
+++ b/naga/src/back/msl/writer.rs
@@ -803,14 +803,21 @@ impl<W: Write> Writer<W> {
         }
 
         self.loop_reachable_macro_name = self.namer.call("LOOP_IS_REACHABLE");
-        let loop_reachable_volatile_name = self.namer.call("unpredictable_jump_over_loop");
-        writeln!(
-            self.out,
-            "#define {} if (volatile bool {} = true; {})",
-            self.loop_reachable_macro_name,
-            loop_reachable_volatile_name,
-            loop_reachable_volatile_name,
-        )?;
+        #[cfg(target_arch = "wasm32")]
+        {
+            let loop_reachable_volatile_name = self.namer.call("unpredictable_jump_over_loop");
+            writeln!(
+                self.out,
+                "#define {} if (volatile bool {} = true; {})",
+                self.loop_reachable_macro_name,
+                loop_reachable_volatile_name,
+                loop_reachable_volatile_name,
+            )?;
+        }
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            writeln!(self.out, "#define {}", self.loop_reachable_macro_name,)?;
+        }
 
         Ok(())
     }