diff --git a/irdb-libs/libIRDB-core/src/operand_csx86.cpp b/irdb-libs/libIRDB-core/src/operand_csx86.cpp
index 986befb9d2f9dd208d1c0b3e50c7122633abf552..73574862bcc778b5cd9dc5676a98523dee81f7fe 100644
--- a/irdb-libs/libIRDB-core/src/operand_csx86.cpp
+++ b/irdb-libs/libIRDB-core/src/operand_csx86.cpp
@@ -178,7 +178,7 @@ static uint32_t to_reg_number(const x86_reg &reg)
 			return 15;
 		default: break;
 	}
-	assert(0);
+	throw std::invalid_argument("Not a register with an associated register number");
 }
 
 // methods