re PR c++/5132 (NaN = 0.0 * HUGE_VAL fails to compile in templates)

re PR c++/5132 (NaN = 0.0 * HUGE_VAL fails to compile in templates)

cp:
	PR c++/5132
	* typeck2.c (digest_init): Make sure non-array core type is
	instantiated.
	* decl2.c (reparse_absdcl_as_casts): Just store the type in the
	constructor, rather than build a new one.
	(build_expr_from_tree, CONSTRUCTOR case): Be careful with the
	PURPOSE of constructor elts.
testsuite:
	* g++.dg/template/ctor1.C: Add instantiation.

From-SVN: r49314