UE4 Asserts not captured on Android

[bruno-garcia]

No description provided.

[tustanivsky]

Unreal Engine plugin uses sentry-java in order to capture various events on Android. For some reason asserts are not captured even though other events and crashes are logged as expected.

Currently, the following packages are in use:

• sentry-5.6.3
• sentry-android-core-5.6.3
• sentry-android-ndk-5.6.3

Here is the log captured with UE when assertion occurs:

Assertion failed: ptr != nullptr [File:/Users/itustanivsky/Work/UnrealProjects/Nineva/SentryUnrealDemo/Plugins/SentrySDK/Source/SentrySDK/Private/SentryLibrary.cpp] [Line: 14]
        Error: === Critical error: ===
        Assertion failed: ptr != nullptr [File:/Users/itustanivsky/Work/UnrealProjects/Nineva/SentryUnrealDemo/Plugins/SentrySDK/Source/SentrySDK/Private/SentryLibrary.cpp] [Line: 14]
        libUE4.so(0x00000000091B1D84)!FDebug::CheckVerifyFailedImpl(char const*, char const*, int, char16_t const*, ...)  []
        libUE4.so(0x0000000007EED52C)!USentryLibrary::Assert()  []
        libUE4.so(0x0000000009839C00)!UObject::execCallMathFunction(UObject*, FFrame&, void*)  []
        libUE4.so(0x000000000983C1EC)!ProcessLocalScriptFunction(UObject*, FFrame&, void*)  []
        libUE4.so(0x000000000983BB84)!void ProcessScriptFunction<void (*)(UObject*, FFrame&, void*)>(UObject*, UFunction*, FFrame&, void*, void (*)(UObject*, FFrame&, void*))  []
        libUE4.so(0x000000000983D0CC)!ProcessLocalFunction(UObject*, UFunction*, FFrame&, void*)  []
        libUE4.so(0x000000000983C1EC)!ProcessLocalScriptFunction(UObject*, FFrame&, void*)  []
        libUE4.so(0x000000000983BEE8)!UObject::ProcessInternal(UObject*, FFrame&, void*)  []
        libUE4.so(0x0000000009640580)!UFunction::Invoke(UObject*, FFrame&, void*)  []
        libUE4.so(0x0000000009841BAC)!UObject::ProcessEvent(UFunction*, void*)  []
        libUE4.so(0x0000000007EEE800)!void TScriptDelegate<FWeakObjectPtr>::ProcessDelegate<UObject>(void*) const  []
        libUE4.so(0x0000000007F1A7D4)!void TMulticastScriptDelegate<FWeakObjectPtr>::ProcessMulticastDelegate<UObject>(void*) const  []
        libUE4.so(0x000000000BE6DF58)!UButton::SlateHandleClicked()  []
        libUE4.so(0x0000000009CCB978)!SButton::ExecuteOnClick()  []
        libUE4.so(0x0000000009CE28A8)!SButton::OnMouseButtonUp(FGeometry const&, FPointerEvent const&)  []
        libUE4.so(0x0000000009B51030)!FSlateApplication::RoutePointerUpEvent(FWidgetPath const&, FPointerEvent const&)  []
        libUE4.so(0x0000000009B15220)!FSlateApplication::ProcessMouseButtonUpEvent(FPointerEvent const&)  []
        libUE4.so(0x0000000009B5B868)!FSlateApplication::OnTouchEnded(FVector2D const&, int, int)  []
        libUE4.so(0x000000000997079C)!FAndroidInputInterface::SendControllerEvents()  []
        libUE4.so(0x000000000996F744)!FAndroidApplication::PollGameDeviceState(float)  []
        libUE4.so(0x0000000007EB24C0)!FEngineLoop::Tick()  []
        libUE4.so(0x0000000007EAA630)!AndroidMain(android_app*)  []
        libUE4.so(0x0000000007EBA0F8)!android_main()  []
        libUE4.so(0x0000000007EE95BC)![Unknown]()  []
        libc.so(0x00000000000EB7A8)![Unknown]()  []
        libc.so(0x000000000008BC8C)![Unknown]()  []

Plugin code for crash/asserts generation.

UE4 assertions reference can be found here.

[bruno-garcia]

Facing this behavior when running the debug build on Android device - even though the app crashes Sentry doesn't capture anything
For some reason SDK acts like this only with asserts while the crashes are logged as expected

[vtzay]

I facing with this on Android and IOS in Development Builds. App has been crashed by fatal log message.

[souredoutlook]

I facing with this on Android and IOS in Development Builds. App has been crashed by fatal log message.

cc @bruno-garcia adding some additional details to the above report:

Using plugin for Unreal Engine version 4.27
Out tests on Android and IOS: capture info message, capture fatal message, and app crash.
Info and fatal messages were captured by sentry from both platforms. But crashes were not on either.
Plugin settings: set DSN, turn on auto initialize.

[souredoutlook]

Hey @vtzay can you let us know exaclty how you're crashing? With Asserts or some other way? Could you try:

    char *ptr = 0;
    *ptr += 1;

?

[tustanivsky]

Hi @souredoutlook, this issue occurs only when using asserts. Here is the sample that is used in the UE plugin demo:

void USentryLibrary::Assert()
{
	char *ptr = nullptr;
	check(ptr != nullptr);
}

The snippet you've shared above crashes the app and the corresponding event captured by Sentry as expected in this case.

P.S. With sentry-java 6.0.0 problem still persists

[vtzay]

Hey @vtzay can you let us know exaclty how you're crashing? With Asserts or some other way? Could you try:

    char *ptr = 0;
    *ptr += 1;

?

Yes it's working ok.

We think it's possible to catch and send crashes on fatal logs using SDK calls.
Unreal may call some code on a non-main thread at the time of the crash before it exits.
For example, we can send a log message as Breadcrumb.
We may try to do this and can share if the result is successful.