[Voted into WP at August, 2010 meeting.]

Proposed resolution (February, 2010):

Change 13.4.3 [temp.arg.nontype] bullet 1.3 as follows:

• the address of an object or function with external linkage, including function templates and function template-ids but excluding non-static class members, expressed (ignoring parentheses) as & id-expression, except that where the & is optional may be omitted if the name refers to a function or array, or and shall be omitted if the corresponding template-parameter is a reference; or

[Drafting note: The change requiring the omission of the & in the reference case fixes an existing problem that is not related to this issue.]

Notes from the March, 2009 meeting:

The consensus of the CWG was that the parentheses should be allowed.

According to 13.4.3 [temp.arg.nontype] paragraph 1, bullet 3, one of the acceptable forms of a non-type, non-template template argument is:

the address of an object or function... expressed as & id-expression where the & is optional if the name refers to a function or array, or if the corresponding template-parameter is a reference

It is not clear from this whether a template argument like (&i) satisfies the requirement or not.