re PR c++/55753 ([C++11][4.7/4.8 Regression] ICE constexpr ctor, tsubst_copy_and_build, at cp/pt.c:14336)

	PR c++/55753
	* tree.c (build_aggr_init_expr): Do nothing in a template.
	* pt.c (tsubst_copy_and_build) [CALL_EXPR]: Strip an ADDR_EXPR off
	a FUNCTION_DECL before tsubsting.

From-SVN: r194986