QT deployed executable crashes on some computers

[Lati]

Hei,

I have a strange issue QT deployed executables which I have been trying to solve since few days. I created an application using QT creator 4.10.2 on QT 5.11.1, using MSVC2015 (OS is Windows 10 Pro, 64 bit). When I deploy the application, executable runs on the development computer without any issue. Then I zip the whole deployment folder and test the same executable (together with the necessary libraries) on 6 different computers. Strangely, executable runs on 3 of them without any issue but crashes on 3 of them (all computers have Windows 10 Pro, 64 bit).

On the computers where it crashes, I get no error when I double click to run the executable, just crashes without any indication and I only see the executable crashes on the Windows event viewer. There is also no sign about the issue in the event viewer logs.

Just to be sure, I installed the same vc++ runtime libraries on all computers including the development computer.

I even tested on 2 different computers which have the same graphic card (though have different driver versions) and same c++ runtime libraries. And executable is running one of them and not running on another.

What might be the issue here or how can I find out the problem what causes the crash?

[hskoglund]

Hi, just guessing but try to turn off Windows Defender runtime protection and see if it makes a difference.

[Lati]

Thanks for your response. All computers have Kaspersky installed hence Windows Defender is disabled.

[JKSH]

1. Did you deploy using windeployqt?
2. Does your app rely on 3rd-party libraries?

@Lati said in QT deployed executable crashes on some computers:

What might be the issue here or how can I find out the problem what causes the crash?

Your different PCs might have different (external) DLLs that get loaded into your app. Try using Dependency Walker to load your app on different PCs (one that crashes and one that doesn't crash) and compare the full list of DLLs.

[Lati]

@JKSH
1-Yes, I used windeployqt
2-There are 3rd party libraries but all of them are provided in the deployment folder at all computers.

I tried both Dependeny Walker and Dependencies. Both give error on all computers which executable runs and crashes.

I doubt if it is related to the graphic cards?

[hskoglund]

Are all of the computers running the same version of Windows 10?
Also, try building your app in Debug mode instead of Release and try that on the crashing PCs (this means you'll have to copy the vc++ debug flavored runtime dlls as well)

[Lati]

@hskoglund Yes, they all have Windows 10 Pro with the latest update.
I tried the Debug mode already and have the same results.

[hskoglund]

Have you tried running your app on the crashing PCs using the Remote Desktop? I.e. turning on the switch "Enable Remote Desktop" in Settings and then remotely running those PCs from your development PC using the Remote Desktop Client

[SGaist]

In addition to my fellows, did you compare the hardware of these machines ? Especially on the graphical card side.

[Lati]

@hskoglund I use remote desktop at all computers :) (though I tried directly using the computers as well)

@SGaist , as I mentioned I also doubt about the graphic cards initially. But I tried on two computers with same specifications including graphic cards (GeForce 605) and both have now same nVidia drivers. And executable crashes only on one of them.

Following is the event viewer log of the crash, maybe someone can take a hint:
"Faulting application name: svchost.exe_TermService, version: 10.0.18362.1, time stamp: 0x32d6c210
Faulting module name: ntdll.dll, version: 10.0.18362.267, time stamp: 0xc00f8a30
Exception code: 0xc0000008
Fault offset: 0x000000000009fe8a
Faulting process ID: 0x5b8
Faulting application start time: 0x01d5a2cd25825160
Faulting application path: C:\WINDOWS\System32\svchost.exe
Faulting module path: C:\WINDOWS\SYSTEM32\ntdll.dll
Report ID: 9b7e234e-f934-4cd5-8ad2-6910fae80b34
Faulting package full name:
Faulting package-relative application ID: "

[SGaist]

@Lati said in QT deployed executable crashes on some computers:

Faulting application name: svchost.exe_TermService

From a quick look that might be network related. Are these computer configured exactly the same ? Connected on the same network ? Is your application using the network ?

[Christian Ehrlicher]

If possible you should enable minidump creation on one of the computers so you can analyze it later on your system. See e.g. here on how to create them

[Lati]

@SGaist, all computers are connected to the company network through LAN.

I am using "webkit" and "webkitwidgets" might be related to the crash?

@Christian-Ehrlicher, I will try that but it is not an easy process since I need permission from our system admin :/

[hskoglund]

"Faulting application name: svchost.exe_TermService,.." means as @SGaist says, it's smells network related.

Try walking up to the crashing PCs, pulling out the network plug and then test your app (but don't tell your system admin about the pulled plug :-)

Edit: Exception code: 0xc0000008 I've seen that when remote debugging across a network, but you get that code also on a Release build?

[Lati]

@hskoglund I plugged out the network cable, no change (admin is on vacation, he will not realise that :))

I tried again debug executable and I have now following error on the computer where it normally crashes:

[JonB]

@Lati
Suggestion then is that your app does indeed attempt to load something off the network?

Meanwhile, I don't understand why your program causes svchost.exe_TermService,.. svchost is to do with Windows Services, I wonder why these are involved in running this application?

[Lati]

@JonB Yes, it loads a website from internet to a *QWebView * control (it is a small website with few kilobytes).

App has nothing to do with Windows Services; at least nothing intentionally coded in the app which uses the Windows Services.

[hskoglund]

Hmm error 0xc0000007b means there's a mixup of 32-bits and 64-bits .dlls. If your app is 32-bit, perhaps you've copied the msvc runtime library .dlls from C:\Windows\System32?
Note that in Windows the 32-bits MSVC runtime .dlls are found in C:\Windows\SysWOW64 and instead C:\Windows\System32 houses the 64-bits one.

[JonB]

@hskoglund
I noted that too. But users says only happens when network cable unplugged! Normally he gets a 0xc0000008 rather than a 0xc0000007b . Strange how that could lead to 32-/64-bit issue?!

[Lati]

@JonB No no, I haven't said it happens only when network cable is unplugged. It happens always with or without internet connection.

@hskoglund I wonder if this is the reason because I use the same deployment on all computers. But, I will check that again.

I hope I can solve this "mystery" soon :/