Suppressing deprecated warnings in Xcode

Question

Since I yet can not add a comment to the @samiq post, I think I will expand it. Input mentioned directive before a function / method in which you use deprecated stuff. Then you can restore the previous setting after the definition of the function end:

#pragma GCC diagnostic push 
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
- (void) methodUsingDeprecatedStuff {
    //use deprecated stuff
}
#pragma GCC diagnostic pop

Clang provides a nice feature that makes the "restore" step in the @manicaesar post independent of the initial warning state:

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
- (void) methodUsingDeprecatedStuff {
    //use deprecated stuff
}
#pragma clang diagnostic pop

To quote the Clang manual:

In addition to all of the functionality provided by GCC's pragma, Clang also allows you to push and pop the current warning state. This is particularly useful when writing a header file that will be compiled by other people, because you don't know what warning flags they build with.

Try -Wno-deprecated-declarations, or its corresponding setting in Xcode, GCC_WARN_ABOUT_DEPRECATED_FUNCTIONS (pro tip: just type in "deprecated" in the build settings to find the specific setting for this warning).

Current versions of Xcode (e.g. Xcode 9.2):

---

Ancient versions of Xcode (e.g. Xcode 2.x, 3.x):

Since we tend to need to support older OSes, but pay attention to our warnings, I wanted a tidier way to do this. I put this together, inspired by some Mozilla code:

#define SILENCE_DEPRECATION(expr)                                   \
do {                                                                \
_Pragma("clang diagnostic push")                                    \
_Pragma("clang diagnostic ignored \"-Wdeprecated-declarations\"")   \
expr;                                                               \
_Pragma("clang diagnostic pop")                                     \
} while(0)

#define SILENCE_IOS7_DEPRECATION(expr) SILENCE_DEPRECATION(expr)
#define SILENCE_IOS8_DEPRECATION(expr) SILENCE_DEPRECATION(expr)

This allows you to do the following:

SILENCE_IOS7_DEPRECATION(return [self sizeWithFont:font constrainedToSize:size]);

It also works with blocks of code:

SILENCE_IOS7_DEPRECATION(
    view = [[MKPolylineView alloc] initWithPolyline:self];
    view.lineWidth = self.lineWidth;
    view.strokeColor = self.color;
);

Also, when you do drop support for pre-iOS 7 devices, you can easily search through the code to find the deprecated usages to fix.