To suppress the LLVM's "PerformSelector may cause a leak because its selector is unknown" warning...

NSObject+BasukeAddition.h

#import <Foundation/Foundation.h>

@interface NSObject(BasukeAddition)

- (id)performSelectorIfExists:(SEL)aSelector;
- (id)performSelectorIfExists:(SEL)aSelector withObject:(id)object;
- (id)performSelectorIfExists:(SEL)aSelector withObject:(id)object1 withObject:(id)object2;

@end

NSObject+BasukeAddition.m

#import "NSObject+BasukeAddition.h"

@implementation NSObject(BasukeAddition)

- (id)performSelectorIfExists:(SEL)aSelector
{
	if ([self respondsToSelector:aSelector] == NO) return nil;
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    return [self performSelector:aSelector];
#pragma clang diagnostic pop
}

- (id)performSelectorIfExists:(SEL)aSelector withObject:(id)object
{
	if ([self respondsToSelector:aSelector] == NO) return nil;
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    return [self performSelector:aSelector withObject:object];
#pragma clang diagnostic pop
}

- (id)performSelectorIfExists:(SEL)aSelector withObject:(id)object1 withObject:(id)object2
{
	if ([self respondsToSelector:aSelector] == NO) return nil;
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    return [self performSelector:aSelector withObject:object1 withObject:object2];
#pragma clang diagnostic pop
	
}

@end