re PR c++/84590 (-fsanitize=undefined internal compiler error: tree check: expected constructor, have target_expr in split_nonconstant_init_1, at cp/typeck2.c:629)

	PR c++/84590
	* cp-gimplify.c (cp_fully_fold): Unwrap TARGET_EXPR or a CONSTRUCTOR
	wrapped in VIEW_CONVERT_EXPR.

	* c-c++-common/ubsan/shift-11.c: New test.

From-SVN: r258132