1*1f5207b7SJohn Levon void push_expression(struct expression_list **estack, struct expression *expr); 2*1f5207b7SJohn Levon struct expression *pop_expression(struct expression_list **estack); 3*1f5207b7SJohn Levon struct expression *top_expression(struct expression_list *estack); 4*1f5207b7SJohn Levon void free_expression_stack(struct expression_list **estack); 5