BUG: Full Koenig Lookup Works Only for Operators

• The C/C++ Compiler (CL.EXE), included with:
  • Microsoft Visual C++, 32-bit Editions, versions 5.0, 6.0

SYMPTOMS

Argument-dependent name lookup, also known as Koenig lookup, works only for operators and not regular functions in a namespace.

CAUSE

The compiler does not fully support argument-dependent name lookup as specified in the C++ Standard. Please refer to the C++ Standard, section 3.4.2, for information on argument-dependent name lookup.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

MORE INFORMATION

Steps to Reproduce Behavior

//test.cpp
// compiler option needed:/GX  
#include <iostream>
namespace N1 {
	struct T1 {
	};
	void g(T1) {
	}
 	T1 operator+( T1 x, T1 y) {
		std::cout<< "In N1::+" <<std::endl;
		return y;
	}
}

int main() {
	N1::T1 t1 ,t2;
	g(t1);	// error C2065: 'g' : undeclared identifier
	t1 + t2; // works fine calls N1::operator+
	return 0;
} 

Additional query words:

Keywords : kbCompiler kbCPPonly kbLangCPP kbVC kbVC500 kbVC500bug kbVC600 kbVC600bug
Version : winnt:5.0,6.0
Platform : winnt
Issue type : kbbug