Open Radar

 
Summary:
The Clang Static Analyzer should warn me when I use an API that isn't available on my deployment target but I fail to wrap it in a respondsToSelector: conditional. The analyzer should automatically recognize and accept simple idioms like this:

	if ([foo respondsToSelector:@selector(bar)]) {
		[foo bar]; // 10.8+
	}

It should also be possible to explicitly mark specific calls as OK via some kind of source annotation.

Steps to Reproduce:
Run the Clang static analyzer on the attached project. It deploys to 10.6, but includes unprotected use of the -[NSBundle loadNibNamed:owner:topLevelObjects:] and -[NSAnimationContext runAnimationGroup:completionHandler:] messages.

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    NSBundle *bundle = [NSBundle mainBundle];
    NSArray *tlo;
    [bundle loadNibNamed:@"Foo" owner:self topLevelObjects:&tlo]; // 10.8
    
    [NSAnimationContext runAnimationGroup:^(NSAnimationContext *context) { // 10.7
        [context setTimingFunction:nil]; // 10.7
        context.allowsImplicitAnimation = YES; // 10.8
    } completionHandler:^{
    }];
}


Expected Results:
The analyzer should warn me about usages of backward-incompatible API calls that aren't wrapped in respondsToSelector: conditionals.

Actual Results:
No analyzer warnings.

Regression:
None

Notes: