[ post-Toronto: Judy provided the above proposed resolution and rationale. ]

[ Toronto: this may be related to issue 120. ]

Rationale:

This terminology is used in section 2.5.2 and 4.1.1 of The C++ Programming Language. It disallows the example in the issue, since the underlying type itself is not user-defined. The only possible problem I can see is for non-type templates, but there's no possible way for a user to come up with a specialization for bitset, for example, that might not have already been specialized by the implementor?

Proposed resolution:

Change "user-defined name" to "user-defined type".

17.4.3.1/1 uses the term "depends" to limit the set of allowed specializations of standard templates to those that "depend on a user-defined name of external linkage."

This term, however, is not adequately defined, making it possible to construct a specialization that is, I believe, technically legal according to 17.4.3.1/1, but that specializes a standard template for a built-in type such as 'int'.

The following code demonstrates the problem:

#include <algorithm>

template<class T> struct X
{
 typedef T type;
};

namespace std
{
 template<> void swap(::X<int>::type& i, ::X<int>::type& j);
}