What does “Thread 1: signal SIGTERM” mean in xcode

问题:

#import <UIKit/UIKit.h>

#import "XYZAppDelegate.h"

int main(int argc, char * argv[]) {
    @autoreleasepool {
            return UIApplicationMain(argc, argv, nil, NSStringFromClass([XYZAppDelegate class]));
    } 
}

The program works fine and I'm just curious about the case. The notification pointed at the 7th line and I could drag it among lines when I do so, a warning showed up warns me the moving of instruction pointer may cause serious problems. So, what's the instruction pointer? Can it disappear?

I really have few programming experiences and I just pick up the iOS programming these days, I hardly know what thread is and I found that SIGTERM is one of the Unix signals which seemed come from nowhere as for me. How does it work? I looked it up in the wiki and found some signals like SIGABRT have similar functions as SIGTERM, what's the difference?

I will truly appreciate your patience if you can solve the problems for a novice like me.

PS: I found it disappears when I quit xcode and reentry it.

回答1:

Pretty much this is a simple bug in Xcode. It seems to just go away whenever Xcode is closed and then reopened.

restart Xcode.

if persistent : click out of the folder you are in, and proceed to your view controller and it should disappear.

hit command S and save and update all of your views, models, etc.