Mat Marcus wrote:
Here is a simplified version of the context in which the problem seems to crop up.
//---- operator.hpp
template <class T> struct is_foo {/*...*/}; // some appropriate compile time test
template <class T> typename boost::enable_if<boost::is_foo<T>, T>::type operator| (T a, T b);
//---- client.cpp
#include "operator.hpp"
So far things are ok. But now suppose that I am using gcc 4.0 the client later includes a new header system_header.hpp.
//---system_header.hpp
enum { kCaseInsenstiveMask = 1L << 1, kReverseOrderMask = 1L << 2, kOverrideMask = 1L << 3};
enum { kTheWorks = kCaseInsenstiveMask | kReverseOrderMask | kOverrideMask };
This is very disturbing; it basically breaks all SFINAE'd operators. If this is what the language currently mandates, it needs to be fixed.