warning:performSelector may cause a leak because its selector is unknown

在ARC项目中使用 performSelector: withObject: 函数出现“performSelector
may cause a leak because its selector is unknown”。在stackoverflow找到了一个解决方案，地址：http://stackoverflow.com/questions/7017281/performselector-may-cause-a-leak-because-its-selector-is-unknown。

主要是警告信息，在非ARC项目中没有这个警告。如果是在某一处修改只需要加入下列代码：

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
[self.ticketTarget performSelector: self.ticketAction withObject: self];//此处是你调用函数的地方
#pragma clang diagnostic pop

如果在程序中多处使用，可以写一个宏定义，如下：

#define SuppressPerformSelectorLeakWarning(Stuff) \
do { \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Warc-performSelector-leaks\"") \
Stuff; \
_Pragma("clang diagnostic pop") \
} while (0)

如果没有返回结果，可以直接按如下方式调用：

SuppressPerformSelectorLeakWarning(
[_target performSelector:_action withObject:self]
);

如果要返回结果，可以按如下方式调用:

id result;
SuppressPerformSelectorLeakWarning(
result = [_target performSelector:_action withObject:self]
);