App crashes on releasing a WKWebView with the delegate of its scrollView is assigned

Originator:jay.shure
Number:rdar://18480729 Date Originated:27/9/2014
Status:Closed Resolved:Duplicated with 18419816
Product:iOS Product Version:8.0.x
Classification:Bug Reproducible:Always
 
Summary:
As the title says, if the scrollView of a WKWebView is configured with a delegate, the program will crash when trying to release the WKWebView instance.

The workaround is to clear the delegate of that scrollView before releasing the WKWebView instance.

Steps to Reproduce:
@import WebKit;
#import "AppDelegate.h"

int main(int argc, char * argv[])
{
  @autoreleasepool {
    WKWebView *wv = [[WKWebView alloc] initWithFrame:CGRectZero];
    wv.scrollView.delegate = (id<UIScrollViewDelegate>)[NSObject new];
    wv = nil;
    return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
  }
}


Expected Results:
The app should start normally.

Actual Results:
App crashes.

Debug output:

malloc: *** error for object 0x7fd6d0f37320: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

Version:
iOS 8.0

Notes:


Configuration:
All the iOS 8 Simulator, iPhone 5s with iOS 8.0.2

Comments


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