FIX: Error Using Inline Assembly in a Template Class

The information in this article applies to:

• The Microsoft C/C++ Compiler (CL.EXE) included with: Microsoft Visual C++, 32-bit Edition, versions 2.0, 2.1, 2.2

SYMPTOMS

If inline assembly is used in an inline member function defined within a templated class, the compiler generates these errors:

  If the assembly instruction is of the form _asm { int 3 }:

       error C2304: '<template class instance> }' : unexpected tokens
                                                    following type
       fatal error C1004: unexpected end of file found.

  If the assembly instruction is of the form _asm int 3:

       fatal error C1075: end of file found before the left <Unknown>
                          at <filename line number> was matched.

NOTE: The same error occurs for macros like ASSERT and VERIFY, which expand to an _asm {int 3} instruction.

RESOLUTION

Define the member function outside the templated class using the "inline" keyword.

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 Microsoft Visual C++, 32-bit Edition, version 4.0.

MORE INFORMATION

Sample Code to Reproduce Problem

/* Compile options needed: /Ob1 or /Ob2 for the workaround function
/*                                      to be inline
*/

 public:
   void good_fun();
   void bad_fun() {
   _asm {int 3}      // This generates a compiler error.
   }
};

   _asm {int 3}      // This doesn't generate an error.
}

void main(void) {
   myclass<int> foo;

In this code, the good_fun() compiles without any error.