ARC forbids Objective-C objects in structs or unions

解决方法有二种：

1。在出错的地方加入__unsafe_unretained

2。关闭系统ＡＲＣ。1.点击project   2.点击Build
Setting    3.找到其以下的Objetive-C Automatic Reference Counting 改后面的YES为NO 即可了

转载：http://linuxp.blog.163.com/blog/static/17096277201261311949260/

typedef struct OFBragDelegateStrings
{
     NSString* prepopulatedText;
     NSString* originalMessage;
} OFBragDelegateStrings;

to

typedef struct OFBragDelegateStrings
{
     __unsafe_unretained NSString* prepopulatedText;
     __unsafe_unretained NSString* originalMessage;
} OFBragDelegateStrings;

參考：http://stackoverflow.com/questions/8093099/arc-forbids-objective-c-objects-in-structs-or-unions-despite-marking-the-file-f