Q133071: FIX: Exception Specification in Template causes C2961 Error

Article: Q133071
Product(s): Microsoft C Compiler
Version(s): 2.0,2.1,2.2,4.0,4.1
Operating System(s): 
Keyword(s): kbcode kberrmsg kbtool kbLangCPP kbVC kbVC500fix
Last Modified: 30-JUL-2001

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The information in this article applies to:

- Microsoft C/C++ Compiler (CL.EXE), included with:
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 2.0, 2.1, 2.2, 4.0, 4.1 
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SYMPTOMS
========

When you use an exception specification in a class or function template, the
following error occurs:

  error C2961: syntax error : 'throw' : unexpected token in template
  declaration

RESOLUTION
==========

Remove the exception specification from the function declaration and definition.
By design, it is not supported.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in Visual C++ version 5.0.

MORE INFORMATION
================

The use of exception specifications is not supported in this version of
Microsoft C++. However, you would expect the compiler to generate the following
warning instead of an error:

  warning C4290: C++ Exception Specification ignored

This level 4 warning is generated as expected when using an exception
specification in a non-templated class or function.

Sample Code to Generate Error C2961 and Demonstrate Problem
-----------------------------------------------------------

   /* Compile options needed: (none)
     */ 
     template <class T>
     class C1 {
     public:
          C1();
          void fn() throw();   // C2961 error - to work around, remove
          "throw()"
     };

     template <class T>
     void C1<T>::fn() throw()  // C2961 error - to work around, remove
     "throw()"
     {}

Sample Code to Generate Warning C4290 and Demonstrate Resolution
----------------------------------------------------------------

     /* Compile options needed: /W4
     */ 
     class C2 {
     public:
          C2();
          void fn() throw(); // compiler correctly generates C4290 warning
     };

     void C2::fn() throw()   // compiler correctly generates C4290 warning
     {}

Additional query words: 9.0 9.00 9.1 9.10 9.2 9.20

======================================================================
Keywords          : kbcode kberrmsg kbtool kbLangCPP kbVC kbVC500fix 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : :2.0,2.1,2.2,4.0,4.1
Issue type        : kbbug
Solution Type     : kbfix

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