stage1 解决defer实现的缺陷

stage1/spl_ast2ir.h

@@ -9,6 +9,7 @@ typedef MAP(spl_def_id_t, spl_ir_node_ref_t) spl_def2ir_map_t;
 
 typedef struct {
     usize cont_blk;
+    usize defer_base;
     const char *label;
     spl_ir_node_ref_vec_t breaks;
     spl_ir_node_ref_t result_slot;