FIX: C1001 on Template Class of Type Pointer to Function (142787)

SYMPTOMS

When instantiating a template class of type pointer to function and then using it as demonstrated in the sample code in the Samples section of this article, you may see the following internal compiler error:

   fatal error C1001: INTERNAL COMPILER ERROR
   (compiler file 'msc1.cpp', line 899)
   Please choose the Technical Support command on the Visual C++
   Help menu, or open the Technical Support help file for more
   information

RESOLUTION

The syntax for instantiating a template class of type pointer to function is:

   TS<void (*)(float)> pf ;

where TS is the name of class template, and pf is the name of the template class being instantiated. You can now instantiate objects of type pf and use them to call functions that accept a float as an argument and return void.

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 following sample code demonstrates the problem and generates the internal compiler error C1001. The workaround is shown in the comments in the sample code.

Sample Code

   /* Compile options needed: none
   */ 
      #include <iostream.h>

      template <class T>
      struct TS
      {
        void TestType(void);
        TS(void) { TestType(); }
      };

     void f(float x)
     {
        cout << "x = " << x << endl ;
     }

     template <class T>
     void TS<T>::TestType(void)
     {
        T t;
        t(2.2); // this line generates a C1001
     }

     void main(void)
     {

       TS<void *(float)> pf;   // this line actually causes the error

       //  Workaround: change the previous line to look like this:
       //  TS<void (*)(float)> pf ;
     }