diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index 7dd639c94c..df9182e924 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -347,7 +347,7 @@ QT_BEGIN_NAMESPACE
     nargs,
 
 #define MOTH_DECODE_ARG(arg, type, nargs, offset) \
-    arg = qFromLittleEndian<type>(reinterpret_cast<const type *>(code)[-nargs + offset]);
+    arg = qFromLittleEndian<type>(qFromUnaligned<type>(reinterpret_cast<const type *>(code) - nargs + offset));
 #define MOTH_ADJUST_CODE(type, nargs) \
     code += static_cast<quintptr>(nargs*sizeof(type) + 1)