PR c++/28211
	* parser.c (cp_parser_template_argument): Don't consider "&var" a
	possible constant-expression.
	* pt.c (convert_nontype_argument): Refine handling of arguments of
	pointer type.
	PR c++/28211
	* g++.dg/tc1/dr49.C: Tweak error messages.
	* g++.dg/parse/template21.C: New test.

From-SVN: r117787