Clang’s New -Wpartial-availability
Clang (via Matt Stevens):
This warns when using decls that are not available on all deployment targets. For example, a call to
- (void)ppartialMethod __attribute__((availability(macosx,introduced=10.8)));will warn if -mmacosx-version-min is set to less than 10.8.
To silence the warning, one has to explicitly redeclare the method like so:
@interface Whatever(MountainLionAPI) - (void)ppartialMethod; @endThis way, one cannot accidentally call a function that isn't available everywhere. Having to add the redeclaration will hopefully remind the user to add an explicit
respondsToSelector:call as well.
I’m not sure why this wasn’t added years ago, when Apple stopped supporting older SDKs, but it’s good to finally have it.
Previously: Deploymate 1.0.
Update (2016-11-11): My strategy is to add -Wpartial-availability to the WARNING_CFLAGS, and then wherever I have a runtime test for the OS version I bracket the code with:
#pragma clang diagnostic push #pragma clang diagnostic ignored "-Wpartial-availability" // Code that uses partially available APIs. #pragma clang diagnostic pop
Any warnings that this does not suppress represent code that needs to have a runtime check added. This seems to be more reliable than Deploymate and has the advantage of being checked every time I compile.
Due to problems inside XCTest, it is necessary to not use -Wpartial-availability in test-related code.