diff --git a/src/compiler/codegen/arm/ArmLIR.h b/src/compiler/codegen/arm/ArmLIR.h
index 3c5daad..bc536f9 100644
--- a/src/compiler/codegen/arm/ArmLIR.h
+++ b/src/compiler/codegen/arm/ArmLIR.h
@@ -822,7 +822,7 @@
     kMaxHoistDistance,
 } ArmTargetOptHints;
 
-extern ArmEncodingMap EncodingMap[kArmLast];
+extern const ArmEncodingMap EncodingMap[kArmLast];
 
 /*
  * Each instance of this struct holds a pseudo or real LIR instruction: