Improve

Author: danog

Zend/zend_alloc.c

@@ -2619,6 +2619,7 @@ ZEND_API void zend_mm_shutdown(zend_mm_heap *heap, bool full, bool silent)
 	ZEND_MM_UNPOISON_CHUNK_HDR(heap->main_chunk);
 	p = heap->main_chunk->next;
 	while (p != heap->main_chunk) {
+		ZEND_MM_UNPOISON_CHUNK_HDR(p);
 		zend_mm_chunk *q = p->next;
 		p->next = heap->cached_chunks;
 		heap->cached_chunks = p;