diff --git a/src/Register.c b/src/Register.c
index 7c9e49d..6a14bf6 100644
--- a/src/Register.c
+++ b/src/Register.c
@@ -132,6 +132,7 @@ struct ZydisRegisterMapItem
 
 static const struct ZydisRegisterMapItem registerMap[] =
 {
+    { ZYDIS_REGCLASS_INVALID  , ZYDIS_REGISTER_NONE   , ZYDIS_REGISTER_NONE   ,   0   ,   0 },
     { ZYDIS_REGCLASS_GPR8     , ZYDIS_REGISTER_AL     , ZYDIS_REGISTER_R15B   ,   8   ,   8 },
     { ZYDIS_REGCLASS_GPR16    , ZYDIS_REGISTER_AX     , ZYDIS_REGISTER_R15W   ,  16   ,  16 },
     { ZYDIS_REGCLASS_GPR32    , ZYDIS_REGISTER_EAX    , ZYDIS_REGISTER_R15D   ,  32   ,  32 },