Update uuid C++ implementation

src/uuid/uuid.h

@@ -24,7 +24,11 @@ struct WUUID {
 
 /* Low level UUID API */
 
+#ifdef WAPP_PLATFORM_CPP
+#define wapp_uuid_create() (WUUID{wapp_str8_buf(UUID_BUF_LENGTH)})
+#else
 #define wapp_uuid_create() ((WUUID){.uuid = wapp_str8_buf(UUID_BUF_LENGTH)})
+#endif
 
 // Just returns the same pointer that was passed in with the UUID initialised.
 // Fails when passed a NULL pointer.