Disable the parser hacks that enabled the "yield" keyword using a future
statement.
diff --git a/Parser/parser.h b/Parser/parser.h
index b0c9a1e..95ec247 100644
--- a/Parser/parser.h
+++ b/Parser/parser.h
@@ -25,7 +25,9 @@
 	stack	 	p_stack;	/* Stack of parser states */
 	grammar		*p_grammar;	/* Grammar to use */
 	node		*p_tree;	/* Top of parse tree */
+#if 0 /* future keyword */
 	int		p_generators;	/* 1 if yield is a keyword */
+#endif
 } parser_state;
 
 parser_state *PyParser_New(grammar *g, int start);