* tree.h (expand_expr_stmt_value): Add maybe_last argument.
	* c-common.h (genrtl_expr_stmt_value): Likewise.
	* stmt.c (expand_expr_stmt): Pass 1 as maybe_last.
	(expand_expr_stmt_value): Add maybe_last argument.
	Don't warn about statement with no effect if it is the last statement
	in expression statement.
	* c-semantics.c (genrtl_expr_stmt): Pass 1 as maybe_last.
	(genrtl_expr_stmt_value): Add maybe_last argument, pass it down to
	expand_expr_stmt_value.
	(expand_stmt) [EXPR_STMT]: Pass 1 as maybe_last to
	genrtl_expr_stmt_value if t is the last EXPR_STMT in its scope.
	* expr.c (expand_expr) [LABELED_BLOCK_EXPR, LOOP_EXPR]: Pass 1
	as maybe_last to expand_expr_stmt_value.

	* gcc.dg/20020104-1.c: New test.

From-SVN: r48541