WebImage Instantly crashes on load when inside a TabView

[mjswen0923]

When used inside a TabView, any loading of a WebImage will immediately cause a crash. Here is the code that causes the crash:

TabView {

            Text("testing")
                .tabItem    {
                    Text("test")
                }
            WebImage(url: URL(string: "https://raw.githubusercontent.com/SDWebImage/SDWebImage/master/SDWebImage_logo.png"))
                .tabItem    {
                    Text("test2")
                }
}

I am using Xcode 12.0 with iOS 14.0, with SDWebImage 5.9.0 and SDWebImageSwiftUI 1.5.0.

Below is the stack trace:

#0 0x00000001b30dcc64 in AG::AttributeID::size() const ()
#1 0x00000001b30d0b2c in AG::Graph::add_indirect_attribute(AG::Subgraph&, AG::AttributeID, unsigned long, std::__1::optional, bool) ()
#2 0x00000001b30e2fe8 in (anonymous namespace)::create_indirect_attribute(unsigned int, std::__1::optional) ()
#3 0x00000001926b5bf4 in partial apply for thunk for @callee_guaranteed () -> (@unowned IndirectAttribute) ()
#4 0x00000001926b5a24 in closure #1 in AGSubgraphRef.apply(_:) ()
#5 0x00000001926b5818 in Attribute.makeReusable(indirectMap:) ()
#6 0x00000001926b1fd0 in closure #1 in closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#7 0x00000001923fd324 in closure #1 in closure #1 in PlaceholderInfo.makeItem(placeholder:seed:) ()
#8 0x0000000192525784 in thunk for @callee_guaranteed (@in_guaranteed _ViewInputs, @guaranteed @escaping @callee_guaranteed (@in_guaranteed _ViewInputs) -> (@out _ViewOutputs)) -> (@out _ViewOutputs?) ()
#9 0x00000001926ad49c in closure #1 in closure #1 in _ViewList_Elements.makeOneElement(at:inputs:indirectMap:body:) ()
#10 0x00000001926b7d58 in partial apply for thunk for @callee_guaranteed (@in_guaranteed _ViewInputs, @guaranteed @escaping @callee_guaranteed (@in_guaranteed _ViewInputs) -> (@out _ViewOutputs)) -> (@out _ViewOutputs?, @unowned Bool) ()
#11 0x00000001926b1e78 in closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#12 0x00000001926b7d94 in partial apply for closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#13 0x00000001926b7d58 in partial apply for thunk for @callee_guaranteed (@in_guaranteed _ViewInputs, @guaranteed @escaping @callee_guaranteed (@in_guaranteed _ViewInputs) -> (@out _ViewOutputs)) -> (@out _ViewOutputs?, @unowned Bool) ()
#14 0x00000001926b1e78 in closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#15 0x00000001926b7d94 in partial apply for closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#16 0x00000001926b7d58 in partial apply for thunk for @callee_guaranteed (@in_guaranteed _ViewInputs, @guaranteed @escaping @callee_guaranteed (@in_guaranteed _ViewInputs) -> (@out _ViewOutputs)) -> (@out _ViewOutputs?, @unowned Bool) ()
#17 0x00000001926b1e78 in closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#18 0x00000001926b7d94 in partial apply for closure #1 in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#19 0x00000001926afe78 in UnaryElements.makeElements(from:inputs:indirectMap:body:) ()
#20 0x00000001926b3350 in SubgraphElements.makeElements(from:inputs:indirectMap:body:) ()
#21 0x00000001926b1d5c in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#22 0x00000001926b1c28 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#23 0x00000001926b1d5c in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#24 0x00000001926b1c28 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#25 0x00000001926b1d5c in closure #1 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#26 0x00000001926b1c28 in ModifiedElements.makeElements(from:inputs:indirectMap:body:) ()
#27 0x00000001926b3350 in SubgraphElements.makeElements(from:inputs:indirectMap:body:) ()
#28 0x00000001926ad420 in closure #1 in ViewList_Elements.makeOneElement(at:inputs:indirectMap:body:) ()
#29 0x00000001923fcedc in closure #1 in PlaceholderInfo.makeItem(placeholder:seed:) ()
#30 0x00000001923fc984 in PlaceholderInfo.updateValue() ()
#31 0x00000001920d83e4 in partial apply for specialized implicit closure #2 in implicit closure #1 in closure #1 in closure #1 in Attribute.init(:) ()
#32 0x00000001b30cc194 in AG::Graph::UpdateStack::update() ()
#33 0x00000001b30cc5c8 in AG::Graph::update_attribute(AG::data::ptrAG::Node, bool) ()
#34 0x00000001b30d5728 in AG::Subgraph::update(unsigned int) ()
#35 0x0000000192738af4 in GraphHost.runTransaction() ()
#36 0x000000019224d780 in ViewGraph.updateOutputs(at:) ()
#37 0x000000019269604c in closure #1 in ViewRendererHost.render(interval:updateDisplayList:) ()
#38 0x0000000192695274 in ViewRendererHost.render(interval:updateDisplayList:) ()
#39 0x000000019214d748 in closure #1 in _UIHostingView.requestImmediateUpdate() ()
#40 0x0000000192801ec0 in thunk for @escaping @callee_guaranteed () -> () ()
#41 0x00000001050f3b68 in _dispatch_call_block_and_release ()
#42 0x00000001050f55f0 in _dispatch_client_callout ()
#43 0x0000000105104890 in dispatch_main_queue_callback_4CF ()
#44 0x000000018b9731e4 in CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE ()
#45 0x000000018b96d3b4 in __CFRunLoopRun ()
#46 0x000000018b96c4bc in CFRunLoopRunSpecific ()
#47 0x00000001a23f1820 in GSEventRunModal ()
#48 0x000000018e310734 in -[UIApplication run] ()
#49 0x000000018e315e10 in UIApplicationMain ()
#50 0x00000001926cd32c in closure #1 in KitRendererCommon(:) ()
#51 0x00000001926cd2b8 in runApp(:) ()
#52 0x0000000192246b08 in static App.main() ()
#53 0x0000000104c130b4 in static SDWebImageTestCrashApp.$main() ()
#54 0x0000000104c13154 in main ()
#55 0x000000018b633e60 in start ()

[yonaskolb]

I'm also getting a crash in iOS 14.0 within the SwiftUI AG Graph when a list item with a WebImage is scrolled onto screen

[mjswen0923]

I'm also getting a crash in iOS 14.0 within the SwiftUI AG Graph when a list item with a WebImage is scrolled onto screen

Was it AGGraph::getValue()? I was experiencing that as well, but this bug was much easier to repro and track down.

[dreampiggy]

Need some dig into SwiftUI issue of this. I didn't realize that user will put this WebImage inside the TabView.

[dreampiggy]

You can wrap that into a empty VStack or HStack.

var body: some View {
    TabView {
        Text("testing")
            .tabItem    {
                Text("test")
            }
        VStack {
            WebImage(url: URL(string: "https://raw.githubusercontent.com/SDWebImage/SDWebImage/master/SDWebImage_logo.png"))
        }
        .tabItem    {
            Text("test2")
        }
    }
}

[yonaskolb]

Was it AGGraph::getValue()? I was experiencing that as well, but this bug was much easier to repro and track down.

Yep

[yonaskolb]

I've created a simple repro project that shows the crash I'm experiencing in lists and buttons in iOS 14.0
SDWebImageCrash.zip

[djr]

I'm also experiencing the AGGraph::getValue() crash but not inside a TabView. The images are in a SwiftUI List view. Wrapping them in an empty VStack or HStack didn't help.

[mjswen0923]

I'm also experiencing the AGGraph::getValue() crash but not inside a TabView. The images are in a SwiftUI List view. Wrapping them in an empty VStack or HStack didn't help.

Yes, I had that problem as well

[dreampiggy]

Need some SwiftUI expert to help. This sounds like Apple's SwiftUI internal changes which effect the current WebImage implementation.

[Baza207]

I'm having a similar issue in a ListView. I have a feeling it's an Async issue, where something returns but the returned thing has already been released by SwiftUI in the background. Harder to catch in a ListView though, but I get exactly the same AGGraph error.

I'm not sure if this is a big in SwiftUI though or something that can be fixed with work arounds, etc.

[WunDaii]

I'm also getting the same AGGraph::getValue() crash inside a List unfortunately.

[ramunasjurgilas]

I am getting this crash as well. HStack or VStack not helping.

[maurovc]

I'm also experiencing this issue. Did someone find a workaround or any info that could help? I'm happy to help even-though I'm not a SwiftUI expert.

Here's my crash stack trace:

Thread 0 name:
Thread 0 Crashed:
0   libsystem_kernel.dylib        	0x00000001b4413414 __pthread_kill + 8
1   libsystem_pthread.dylib       	0x00000001d092bb40 pthread_kill + 272 (pthread.c:1388)
2   libsystem_c.dylib             	0x0000000190838b74 abort + 104 (abort.c:110)
3   libswiftCore.dylib            	0x000000018b448f68 swift::fatalError(unsigned int, char const*, ...) + 60 (Errors.cpp:393)
4   libswiftCore.dylib            	0x000000018b4490c0 swift::swift_abortRetainUnowned(void const*) + 36 (Errors.cpp:460)
5   libswiftCore.dylib            	0x000000018b49888c swift_unknownObjectUnownedLoadStrong + 76 (SwiftObject.mm:895)
6   SwiftUI                       	0x000000018dee6ad0 ViewGraph.graphDelegate.getter + 16 (ViewGraph.swift:234)
7   SwiftUI                       	0x000000018e3f994c GraphHost.flushTransactions() + 204 (GraphHost.swift:441)
8   SwiftUI                       	0x000000018e3f8e10 specialized GraphHost.asyncTransaction<A>(_:mutation:style:) + 252 (<compiler-generated>:0)
9   SwiftUI                       	0x000000018dff0500 AttributeInvalidatingSubscriber.invalidateAttribute() + 236 (AttributeInvalidatingSubscriber.swift:89)
10  SwiftUI                       	0x000000018dff03fc AttributeInvalidatingSubscriber.receive(_:) + 100 (AttributeInvalidatingSubscriber.swift:53)
11  SwiftUI                       	0x000000018dff0b18 protocol witness for Subscriber.receive(_:) in conformance AttributeInvalidatingSubscriber<A> + 24 (<compiler-generated>:0)
12  SwiftUI                       	0x000000018e19379c SubscriptionLifetime.Connection.receive(_:) + 100 (SubscriptionLifetime.swift:195)
13  Combine                       	0x000000019b0b900c ObservableObjectPublisher.Inner.send() + 136 (ObservableObject.swift:115)
14  Combine                       	0x000000019b0b87b4 ObservableObjectPublisher.send() + 632 (ObservableObject.swift:153)
15  Combine                       	0x000000019b0a16e8 PublishedSubject.send(_:) + 136 (PublishedSubject.swift:82)
16  Combine                       	0x000000019b0c7ffc specialized static Published.subscript.setter + 388 (Published.swift:0)
17  Combine                       	0x000000019b0c75dc static Published.subscript.setter + 40 (<compiler-generated>:0)
18  Project Calathea              	0x0000000101090054 _hidden#1975_ + 364 (__hidden#2238_:0)
19  SwiftUI                       	0x000000018df08338 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0)
20  SwiftUI                       	0x000000018df08360 thunk for @escaping @callee_guaranteed () -> (@out ()) + 28 (<compiler-generated>:0)
21  SwiftUI                       	0x000000018df08338 thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:0)
22  SwiftUI                       	0x000000018def70f0 static Update.end() + 536 (<compiler-generated>:0)
23  SwiftUI                       	0x000000018ddff054 AppearanceEffect.disappeared() + 332 (Update.swift:45)
24  SwiftUI                       	0x000000018ddff2dc static AppearanceEffect.willRemove(attribute:) + 48 (AppearanceActionModifier.swift:105)
25  SwiftUI                       	0x000000018df16b3c closure #1 in AGSubgraphRef.willRemove() + 80 (AttributeGraphAdditions.swift:83)
26  AttributeGraph                	0x00000001afa4066c AG::Subgraph::apply(unsigned int, AG::ClosureFunctionAV<void, unsigned int>) + 420 (ag-closure.h:108)
27  SwiftUI                       	0x000000018e3f97f4 GraphHost.updateRemovedState() + 152 (<compiler-generated>:0)
28  SwiftUI                       	0x000000018e4c8010 _UIHostingView.updateRemovedState() + 112 (GraphHost.swift:107)
29  SwiftUI                       	0x000000018e4ca154 _UIHostingView.__deallocating_deinit + 52 (UIHostingView.swift:1437)
30  SwiftUI                       	0x000000018e4ca22c @objc _UIHostingView.__deallocating_deinit + 28 (<compiler-generated>:0)
31  libobjc.A.dylib               	0x000000019ba8a7b0 AutoreleasePoolPage::releaseUntil(objc_object**) + 204 (NSObject.mm:944)
32  libobjc.A.dylib               	0x000000019ba8a650 objc_autoreleasePoolPop + 212 (NSObject.mm:1211)
33  UIKitCore                     	0x000000018a3e0104 -[UIView dealloc] + 876 (UIView.m:4639)
34  libobjc.A.dylib               	0x000000019ba69b10 object_cxxDestructFromClass(objc_object*, objc_class*) + 112 (objc-class.mm:455)
35  libobjc.A.dylib               	0x000000019ba80840 objc_destructInstance + 80 (objc-class.mm:469)
36  libobjc.A.dylib               	0x000000019ba8780c _objc_rootDealloc + 80 (objc-runtime-new.mm:8131)
37  UIKitCore                     	0x0000000189ef8928 -[UIResponder dealloc] + 156 (UIResponder.m:136)
38  UIKitCore                     	0x000000018a3e0120 -[UIView dealloc] + 904 (UIView.m:4640)
39  UIKitCore                     	0x00000001896020b8 -[UICollectionViewCell dealloc] + 108 (UICollectionViewCell.m:910)
40  libobjc.A.dylib               	0x000000019ba8a7b0 AutoreleasePoolPage::releaseUntil(objc_object**) + 204 (NSObject.mm:944)
41  libobjc.A.dylib               	0x000000019ba8a650 objc_autoreleasePoolPop + 212 (NSObject.mm:1211)
42  QuartzCore                    	0x000000018a87ff60 CA::Context::commit_transaction(CA::Transaction*, double, double*) + 544 (CAInternal.h:330)
43  QuartzCore                    	0x000000018a8ab36c CA::Transaction::commit() + 732 (CATransactionInternal.mm:449)
44  QuartzCore                    	0x000000018a8ac6fc CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 96 (CATransactionInternal.mm:925)
45  CoreFoundation                	0x000000018748f358 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 36 (CFRunLoop.c:1799)
46  CoreFoundation                	0x00000001874895c4 __CFRunLoopDoObservers + 576 (CFRunLoop.c:1912)
47  CoreFoundation                	0x0000000187489b74 __CFRunLoopRun + 1056 (CFRunLoop.c:2953)
48  CoreFoundation                	0x000000018748921c CFRunLoopRunSpecific + 600 (CFRunLoop.c:3242)
49  GraphicsServices              	0x000000019e508784 GSEventRunModal + 164 (GSEvent.c:2259)
50  UIKitCore                     	0x0000000189ec2200 -[UIApplication _run] + 1072 (UIApplication.m:3266)
51  UIKitCore                     	0x0000000189ec7a74 UIApplicationMain + 168 (UIApplication.m:4738)
52  Project Calathea              	0x0000000100fe7770 main + 68 (Auth.swift:7)
53  libdyld.dylib                 	0x00000001871496c0 start + 4

Thanks!