re PR c++/49264 (Internal compiler error: segmentation fault)

re PR c++/49264 (Internal compiler error: segmentation fault)

	PR c++/49264
	* gimple-fold.c (fold_stmt_1): Don't try to fold *& on the lhs
	if stmt folded into nothing.
	* tree-inline.c (fold_marked_statements): If a builtin at the
	end of a bb folded into nothing, just update cgraph edges
	and move to next bb.
	* cgraph.c (cgraph_update_edges_for_call_stmt_node): Allow new_stmt
	to be NULL.  Don't compute count and frequency if new_call is NULL.

	* g++.dg/opt/pr49264.C: New test.

From-SVN: r174711