The C++ compiler has additional extensions that you can activate. There is no item in the C/C++ Language Panel to activate these extensions. You must turn on the pragma cpp_extensions.

If this pragma is on, the compiler lets you use these extensions to the ANSI/ISO C++ standard:

• Anonymous struct objects (ARM, §9). For example:

---

#pragma cpp_extensions on
void foo()
{
  union {
    long       hilo;
    struct { short hi, lo; }; 
      //  anonymous struct
  };
  hi=0x1234; 
  lo=0x5678;
      //  hilo==0x12345678      
}

---

• Unqualified pointer to a member function (ARM, §8.1c). For example:

---

#pragma cpp_extensions on
struct Foo { void f(); }
void Foo::f()
{
  void (Foo::*ptmf1)() = &Foo::f;
    // ALWAYS OK

  void (Foo::*ptmf2)() = f;
    // OK, if cpp_extensions is on. 
}

---

See also "cpp_extensions" and "Checking Options."