Why are static member functions called only in the global scope if they have a return value?

Question

I found something peculiar: static member functions of a class / structure cannot be called a global scope if they do not have a return value.

This program does not compile:

struct test
{
  static void dostuff()
  {
      std::cout << "dostuff was called." << std::endl;
  }
};

test::dostuff();

int main()
{  
   return 0;
}

Providing us with the following in GCC v4.8.3:

main.cpp:12:16: error: expected constructor, destructor, or type conversion before ';' token
test::dostuff();
               ^

However, adding the return value to dostuff()and assigning it to a global variable, the program compiles and works as intended:

struct test
{
  static int dostuff()
  {
      std::cout << "dostuff was called." << std::endl;
      return 0;
  }
};

int i = test::dostuff();

int main()
{
   return 0;
}

This gives the expected result:

dostuff was called.

Can someone explain to me why this is so, and if there is a workaround that is not related to creating global variables?

Answer 1

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Answer 2

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