diff --git a/include/boo/System.hpp b/include/boo/System.hpp
index 509bec2..15cfe4f 100644
--- a/include/boo/System.hpp
+++ b/include/boo/System.hpp
@@ -29,33 +29,33 @@ static inline ComPtr<T>* ReferenceComPtr(ComPtr<T>& ptr) {
 
 #ifndef ENABLE_BITWISE_ENUM
 #define ENABLE_BITWISE_ENUM(type)                                                                                      \
-  constexpr type operator|(type a, type b) {                                                                           \
+  constexpr type operator|(type a, type b) noexcept {                                                                  \
     using T = std::underlying_type_t<type>;                                                                            \
     return type(static_cast<T>(a) | static_cast<T>(b));                                                                \
   }                                                                                                                    \
-  constexpr type operator&(type a, type b) {                                                                           \
+  constexpr type operator&(type a, type b) noexcept {                                                                  \
     using T = std::underlying_type_t<type>;                                                                            \
     return type(static_cast<T>(a) & static_cast<T>(b));                                                                \
   }                                                                                                                    \
-  constexpr type& operator|=(type& a, type b) {                                                                        \
+  constexpr type& operator|=(type& a, type b) noexcept {                                                               \
     using T = std::underlying_type_t<type>;                                                                            \
     a = type(static_cast<T>(a) | static_cast<T>(b));                                                                   \
     return a;                                                                                                          \
   }                                                                                                                    \
-  constexpr type& operator&=(type& a, type b) {                                                                        \
+  constexpr type& operator&=(type& a, type b) noexcept {                                                               \
     using T = std::underlying_type_t<type>;                                                                            \
     a = type(static_cast<T>(a) & static_cast<T>(b));                                                                   \
     return a;                                                                                                          \
   }                                                                                                                    \
-  constexpr type operator~(type key) {                                                                                 \
+  constexpr type operator~(type key) noexcept {                                                                        \
     using T = std::underlying_type_t<type>;                                                                            \
     return type(~static_cast<T>(key));                                                                                 \
   }                                                                                                                    \
-  constexpr bool True(type key) {                                                                                      \
+  constexpr bool True(type key) noexcept {                                                                             \
     using T = std::underlying_type_t<type>;                                                                            \
     return static_cast<T>(key) != 0;                                                                                   \
   }                                                                                                                    \
-  constexpr bool False(type key) {                                                                                     \
+  constexpr bool False(type key) noexcept {                                                                            \
     using T = std::underlying_type_t<type>;                                                                            \
     return static_cast<T>(key) == 0;                                                                                   \
   }