diff --git a/src/calibre/utils/cpp_binding.h b/src/calibre/utils/cpp_binding.h
index 1fd9e52932..d5e8712c3e 100644
--- a/src/calibre/utils/cpp_binding.h
+++ b/src/calibre/utils/cpp_binding.h
@@ -18,7 +18,10 @@
 
 #define arraysz(x) (sizeof(x)/sizeof(x[0]))
 
-template<typename T=void*, void free_T(T)=free, T null=static_cast<T>(NULL)>
+template<typename T>
+static inline T generic_null_getter(void) { return T{}; }
+
+template<typename T=void*, void free_T(T)=free, T null_getter(void)=generic_null_getter>
 class generic_raii {
 	private:
 		generic_raii( const generic_raii & ) noexcept;
@@ -28,23 +31,23 @@ class generic_raii {
 		T handle;
 
 	public:
-		explicit generic_raii(T h = null) noexcept : handle(h) {}
+		generic_raii() noexcept { handle = null_getter(); }
+		explicit generic_raii(T h) noexcept : handle(h) {}
 		~generic_raii() noexcept { release(); }
 
 		void release() noexcept {
-			if (handle != null) {
+			if (handle != null_getter()) {
                 T temp = handle;
-				handle = null;
+				handle = null_getter();
 				free_T(temp);
 			}
 		}
 
 		T ptr() noexcept { return handle; }
-		T detach() noexcept { T ans = handle; handle = null; return ans; }
+		T detach() noexcept { T ans = handle; handle = null_getter(); return ans; }
 		void attach(T val) noexcept { release(); handle = val; }
 		T* unsafe_address() noexcept { return &handle; }
-		explicit operator bool() const noexcept { return handle != null; }
-
+		explicit operator bool() const noexcept { return handle != null_getter(); }
 };
 
 template<typename T>
diff --git a/src/calibre/utils/windows/common.h b/src/calibre/utils/windows/common.h
index 1ae3b57e99..e37feafaa6 100644
--- a/src/calibre/utils/windows/common.h
+++ b/src/calibre/utils/windows/common.h
@@ -64,33 +64,9 @@ typedef generic_raii<wchar_t*, co_task_mem_free> com_wchar_raii;
 
 static inline void mapping_raii_free(void *x) { UnmapViewOfFile(x); }
 typedef generic_raii<void*, mapping_raii_free> mapping_raii;
-
-class handle_raii {
-	private:
-		handle_raii( const handle_raii & ) noexcept;
-		handle_raii & operator=( const handle_raii & ) noexcept ;
-
-	protected:
-		HANDLE handle;
-
-	public:
-		explicit handle_raii(HANDLE h = INVALID_HANDLE_VALUE) noexcept : handle(h) {}
-		~handle_raii() noexcept { release(); }
-
-		void release() noexcept {
-			if (handle != INVALID_HANDLE_VALUE) {
-                HANDLE temp = handle;
-				handle = INVALID_HANDLE_VALUE;
-				CloseHandle(temp);
-			}
-		}
-
-		HANDLE ptr() noexcept { return handle; }
-		HANDLE detach() noexcept { HANDLE ans = handle; handle = INVALID_HANDLE_VALUE; return ans; }
-		void attach(HANDLE val) noexcept { release(); handle = val; }
-		explicit operator bool() const noexcept { return handle != INVALID_HANDLE_VALUE; }
-};
-
+static inline HANDLE invalid_handle_value_getter(void) { return INVALID_HANDLE_VALUE; }
+static inline void close_handle(HANDLE x) { CloseHandle(x); }
+typedef generic_raii<HANDLE, close_handle, invalid_handle_value_getter> handle_raii;
 
 struct prop_variant : PROPVARIANT {
 	prop_variant(VARTYPE vt=VT_EMPTY) noexcept : PROPVARIANT{} { PropVariantInit(this); this->vt = vt;  }