How to get rid of "C++ exception specification ignored" warning

Question

Hi,

I recently got a dll that has been implemented by others. I have to use it in my application. In the header file of their class they have the function declaration

void func1() throw (CCustomException);

Now when i compile it am getting the warning,

C++ exception specification ignored except to indicate a function is not _declspec(nothrow)

I read the MSDN - Documentation but couldn't understand it clearly. Also, I don't want to disable the warning just because it is showing up. I want to know what I am doing wrong instead of disabling it.

I thought my function, say myfunc() accessing that func1() from the dll doesn't have that Exception specification list. Hence I tried having the corresponding exception specification list in my function too as,

void myfunc1() throw (CCustomException);

But I am still getting the warning. What is that warning is all about and how to get rid of it? I am using Qt 4.5 in Windows XP.

Answer 1

Ok, it is a non-answer, but I would throw away the exception specification and never use it again.

EDIT: I read too fast, and I didn't see you did not write the class yourself. Best way to get rid of warnings in msvc is via #pragma warning(push) followed by #pragma warning(disable:xxxx) where xxxx is the warning code :

#ifdef _MSC_VER 
#pragma warning(push)
#pragma warning(disable:xxxx)
#endif 

...

#ifdef _MSC_VER 
#pragma warning(pop)
#endif

EDIT: It is perfectly safe to disable the warning. Exception specifications are evil, and the compiler is only telling you it is disabling them for you. Even if it breaks the standard.

Answer 2

You might try playing with preprocessor:

#ifdef _SOME_MSVC_DEFINE
#  define _throw(foo)
#else
#  define _throw(foo) throw(foo)
#endif

void myfunc1() _throw (CCustomException);

Or, try to disable that warning in Visual Studio.

Answer 3

I found this link, which I found useful. Just added if it might be helpful to someone..