SEH exception with code 0xc0000005 thrown in the test body

A SEH (Structured Exception Handling) exception is not a C++-exception that can be handled using c++-language constructs (try-catch) but it is raised from windows itself and points to some fundamental flaw. SEH-exceptions are very annoying because they do not cause normal stack unwinding which can lead to unclosed files or not-unlocked mutexes that should normally cleared by the destructors of the owning object. I have encountered SEH-exceptions when accessing memory that does not belong to the current process so I recommend looking at memory-related instructions in the constructor and destructor of CSig. You can read about SEH, for instance, here

The way I just found the problem was that in Visual Studio I went to Debug->Exceptions, and checked everything in the first column. Then run/debug your unit tests, and it will throw an exception on the line that the problem is at. That's where you need to debug/fix it.

I ran into this very problem using GoogleTest with Visual Studio 2010. Our setup involves creating a library for the GoogleTest Frameworks, which is then linked against our individual Unit Tests. I recently updated the Frameworks support and recompiled it from scratch. After doing this, I encountered the exception described above.

After a bit of digging, I discovered that the 'Struct Member Alignment' setting was the culprit:

Project properties > Configuration Properties > C/C++ > Code Generation > Struct Member Alignment

While the Frameworks project had the setting set to 'default', the corresponding Unit Test project had it configured to "1 Byte /Zp1". Once I changed them to have the same alignment, the problem went away.

For me it appeared to be a null reference error. Some method was called on a nullptr and for reasons unclear to me it didn’t fail immediately but just started executing. The SEH error presumably occurred as soon as unallocated memory was accessed. So check for null pointers!

I am having a similar issue and its pertaining to un-initialized variables and running the test in release build. I had a char * un-initialized after which initialized to NULL seems to have fixed the issue.

If you are using Visual Studio 2013, check the Thrown box for Win32 exceptions (specifically access violation) in Debug>Exceptions. This will let you debug which line has the issue. This might be useful since the debugger will not break if your program normally raises other exceptions.