FIX: SEH exceptions are caught by wrong exception handler when asynchronous exception handling is enabled in WEC 2013

Symptoms

Consider the following scenario:

• You use the Application Builder plug-in for Visual Studio 2013 to create a C++ application that targets Windows Embedded Compact 2013.

• You enable the asynchronous exception handling by using the "/EHa" compiler switch. This switch allows both C++ synchronous and structured exception handling (SEH) asynchronous exception handling methods to be mixed in the same code.

• You run the related code to catch SEH exceptions.

In this scenario, SEH exceptions are always caught in the very first exception handler even if it's filtered for a C++ synchronous exception. 

The expected behavior is SEH exceptions being caught by the ellipsis exception handler.

For example, you run the following sample code:class CMyEx
{
public:
CMyEx(int nParam) : m_nParam(nParam) { }
int m_nParam;
};

void TestExceptions()
{
try
{
int a = 42;
int b = 0;
// throw CMyEx(1);
// throw 97;
int c = a / b;
}
catch (const CMyEx &e)
{
wprintf(L"CMyEx exception caught (param=%d)!\n", e.m_nParam);
}
catch (...)
{
wprintf(L"Exception of unspecified type caught by ellipsis clause!\n");
}
} In this sample, you always hit the first catch clause when the SEH exception (integer divide by zero) occurs instead of the ellipsis handler as expected.

Resolution

References

Learn about the terminology that Microsoft uses to describe software updates.