Category 

Modifiers, Keyword extensions, Storage class specifiers 

Syntax  

__declspec( noreturn ) declarator

This __declspec attribute tells the compiler that a function does not return. As a consequence, the compiler knows that the code following a call to a __declspec(noreturn) function is unreachable.  

If the compiler finds a function with a control path that does not return a value, it generates a warning. If the control path cannot be reached due to a function that never returns, you can use __declspec(noreturn) to prevent this warning or error.  

Example 

Consider the following code. The else clause does not contain a return statement, so the programmer declares fatal as __declspec(noreturn) to avoid an error or warning message.

__declspec(noreturn) extern void fatal ()
{
   // Code omitted
}
int foo()
{
   if(...)
      return 1;
   else if(...)
      return 0;
   else
      fatal();
}