87 #define __TREE_DFS_PUSH(scratch, var) \  argument
88 	(assert(&(scratch)->stack[sizeof((scratch)->stack)] > (scratch)->sp), \
89 	 *(++((scratch)->sp)) = (var))
90 #define __TREE_DFS_POP(scratch) \  argument
91 	(*(((scratch)->sp)--))
93 #define TREE_DFS_FOREACH(var, root, scratch, field) \  argument
94 	for ((scratch)->stack[0] = NULL, (scratch)->sp = (scratch)->stack, \
98 			? __TREE_DFS_PUSH(scratch, (var)->field.tn_younger) : 0), \
101 			? (var)->field.tn_younger : __TREE_DFS_POP(scratch))
103 #define TREE_DFS_FOREACH_SELECTIVE(var, root, scratch, field, sel) \  argument
104 	for ((scratch)->stack[0] = NULL, (scratch)->sp = (scratch)->stack, \
108 			? __TREE_DFS_PUSH(scratch, (var)->field.tn_younger) : 0), \
111 			? (var)->field.tn_younger : __TREE_DFS_POP(scratch))
113 #define __TREE_BFS_ENQUEUE(scratch, var) \  argument
114 	(*(((scratch)->tail)++) = (var))
115 #define __TREE_BFS_DEQUEUE(scratch) \  argument
116 	(*(((scratch)->head)++))
118 #define TREE_BFS_FOREACH(var, root, scratch, field) \  argument
119 	for ((scratch)->head = (scratch)->tail = (scratch)->queue, \
124 			  (__TREE_BFS_ENQUEUE(scratch, (var)->field.tn_first), \
126 			: (scratch)->head != (scratch)->tail \
128 				  (__TREE_BFS_ENQUEUE(scratch, (var)->field.tn_first), \
129 				   __TREE_BFS_DEQUEUE(scratch)) \
135 			: (scratch)->head != (scratch)->tail \
137 				  __TREE_BFS_DEQUEUE(scratch) \
140 #define TREE_BFS_FOREACH_SELECTIVE(var, root, scratch, field, sel) \  argument
141 	for ((scratch)->head = (scratch)->tail = (scratch)->queue, \
146 			  (__TREE_BFS_ENQUEUE(scratch, (var)->field.tn_first), \
148 			: (scratch)->head != (scratch)->tail \
150 				  (__TREE_BFS_ENQUEUE(scratch, (var)->field.tn_first), \
151 				   __TREE_BFS_DEQUEUE(scratch)) \
157 			: (scratch)->head != (scratch)->tail \
159 				  __TREE_BFS_DEQUEUE(scratch) \