In my application I use 3rd party code that triggers some warnings. I reviewed them and they can be safely ignored.
Now I want to "mark" a file somehow, so Xcode won't show any warnings for the code in that file.
How should I do that?
Select your target and show Build Phases. Then enter the name of the file in the search box, and you should see it listed in the Compile Sources phase. Double-click in the Compiler Flags column for that file and enter -w to turn off all warnings for that file.