* tree.def (documentation): Remove mention of class 'b'.
	(BLOCK): Now in class 'x'.
	* c-common.c (verify_tree): Remove case 'b'.
	* c-typeck.c (same_translation_unit_p): Change 'b' to 'x'.
	* calls.c (calls_function_1): Control cannot get past the switch
	when exp is a BLOCK.
	* print-tree.c (print_node): Move code for class 'b' to the class
	'c'/'x' switch, as case BLOCK.
	* tree.c (tree_size, make_node_stat, tree_node_structure): Likewise.
	(unsafe_for_reeval, substitute_placeholder_in_expr)
	(stabilize_reference_1): Remove case 'b'.
	* tree-browser.c (browse_tree): Change all tests for TREE_CODE_CLASS
	of something being 'b' to tests for TREE_CODE of something being
	BLOCK.
	* tree-ssa-operands.c (get_expr_operands): Likewise.
ada:
	* trans.c (gnat_stabilize_reference_1): Remove case 'b'.

From-SVN: r81831