About Clang Warning

I’m using Clang/scan-build xcodebuild to build Objective-C projects, There are many warnings such as [-Wgnu-conditional-omitted-operand] warning log. I want to disable other all warnings but let one warning like [-Wformat-pedantic] leaved. There is an option -w to suppress all warnings, but add adition -Wformat-pedantic flag after -w, it is not worked, no warning is print. Is there any suggest?

-Wno-everything -Wformat-pedantic might work