Patch for constexpr variable templates

[Jason Merrill]

On 07/30/2014 05:33 PM, Braden Obrzut wrote:
> On 07/30/2014 04:44 PM, Jason Merrill wrote:
>> Why not do this in cp_parser_id_expression?

> I did mention this in the original mail, is this definitely the way it
> should be done?

In the original mail you mentioned doing it in cp_parser_template_id; I 
agree that we probably don't want to do it there because of the 
complications you are seeing.  I was thinking about doing it when we 
normally resolve an id-expression that refers to a variable, once we 
know we're looking at an expression and not a declarator-id.  But I 
think my suggestion of cp_parser_id_expression was wrong, and it would 
be better in finish_id_expression.

Jason