diff --git a/src/core/arm/dynarmic/arm_dynarmic.h b/src/core/arm/dynarmic/arm_dynarmic.h
index 02467f8795..559dbf5a81 100644
--- a/src/core/arm/dynarmic/arm_dynarmic.h
+++ b/src/core/arm/dynarmic/arm_dynarmic.h
@@ -17,7 +17,7 @@ class MemorySystem;
 } // namespace Memory
 
 namespace Core {
-struct System;
+class System;
 }
 
 class DynarmicUserCallbacks;
diff --git a/src/core/arm/dyncom/arm_dyncom.h b/src/core/arm/dyncom/arm_dyncom.h
index 2bb0212b3d..99c6ab4601 100644
--- a/src/core/arm/dyncom/arm_dyncom.h
+++ b/src/core/arm/dyncom/arm_dyncom.h
@@ -11,7 +11,7 @@
 #include "core/arm/skyeye_common/armstate.h"
 
 namespace Core {
-struct System;
+class System;
 }
 
 namespace Memory {